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Authors: Edna Madai Méndez-Hernández, Jesús Hernández-Tinoco, José Manuel Salas-Pacheco, Luis Francisco Sánchez-Anguiano, Oscar Arias-Carrión, Ada Agustina Sandoval-Carrillo, Francisco Xavier Castellanos-Juárez, Luis Ángel Ruano-Calderón and Cosme Alvarado-Esquivel

Abstract

The link between Toxoplasma gondii infection and multiple sclerosis remains controversial. In the present study, we aimed to determine the association between T. gondii seropositivity and multiple sclerosis. Using an age- and gender-matched case-control study, we studied 45 patients who had multiple sclerosis attended in two public hospitals and 225 control subjects without this disease and other neurological disorders in Durango City, Mexico. Serum samples of cases and controls were analyzed for detection of anti-Toxoplasma IgG using a commercially available enzyme-linked immunoassay. One (2.22%) of the 45 patients with multiple sclerosis, and 15 (6.67%) of the 225 control subjects without this disease were seropositive for anti-T. gondii IgG antibodies. No statistically significant difference (OR = 0.31; 95% CI: 0.04–2.47; P = 0.48) in seroprevalence of anti-T. gondii IgG antibodies between cases and controls was found. The frequency of T. gondii seropositivity did not vary among cases and controls about sex or age groups. Results of this study do not support an association between seropositivity to T. gondii and multiple sclerosis. However, additional research with larger sample sizes to confirm this lack of association should be conducted.

Open access

Abstract

Listeria monocytogenes (Lm) is a food-borne pathogen with a high chance of infecting neonates, pregnant women, elderly and immunocompromised individuals. Lm infection in neonates can cause neonatal meningitis and sepsis with a high risk of severe neurological and developmental sequelae and high mortality rates. However, whether an acute neonatal Lm infection causes long-term effects on the immune system persisting until adulthood has not been fully elucidated. Here, we established a neonatal Lm infection model and monitored the composition of major immune cell subsets at defined time points post infection (p.i.) in secondary lymphoid organs and the intestine. Twelve weeks p.i., the CD8+ T cell population was decreased in colon and mesenteric lymph nodes (mLNs) with an opposing increase in the spleen. In the colon, we observed an accumulation of CD4+ and CD8+ effector/memory T cells with an increase of T-bet+ T helper 1 (Th1) cells. In addition, 12 weeks p.i. an altered composition of innate lymphoid cell (ILC) and dendritic cell (DC) subsets was still observed in colon and mLNs, respectively. Together, these findings highlight organ-specific long-term consequences of an acute neonatal Lm infection on both the adaptive and innate immune system.

Open access

Abstract

Introduction

Chronic sinusitis caused by anaerobes is a particular concern clinically, because many of the complications are associated with infections caused by these organisms. The aim of this study was to evaluate the incidence of anaerobic bacteria in chronic sinusitis in adults as a part of a prospective microbiological study.

Materials and methods

Over a one-year period, aspirations of maxillary sinus secretions and/or ethmoid cavities were derived in n = 79 adult patients with chronic sinusitis by endoscopy in a tertiary-care teaching hospital in Hungary. The qualitative and quantitative compositions of the total cultivable aerobic and anaerobic bacterial and fungal flora cultured on the samples were compared. Correct anaerobic species level identifications were carried out according to standard methods.

Results

Bacteria were recovered for all of the 79 aspirates and the numbers of the significant cultured isolates (with colony forming units ≥103) were between 1 and 10. A total of 206 isolates, 106 anaerobic and 100 aerobic or facultative-anaerobic strains were isolated. The most common aerobic bacteria were Streptococcus pneumoniae (n = 40), Haemophilus influenzae (n = 29), Moraxella catarrhalis (n = 6), Staphylococcus aureus (n = 7) and Streptococcus pyogenes (n = 6). The anaerobic bacteria included black-pigmented Prevotella spp. and Porphyromonas spp. (n = 27), Actinomyces spp. (n = 13), Gram-positive anaerobic cocci (n = 16), Fusobacterium spp. (n = 19) and Cutibacterium acnes (n = 8).

Conclusions

This study illustrates the microbial dynamics in which anaerobic and aerobic bacteria prevail and highlights the importance of obtaining cultures from patients with chronic sinusitis for guidance in selection of proper antimicrobial therapy.

Open access

Abstract

Obligate anaerobic bacteria are considered important constituents of the microbiota of humans; in addition, they are also important etiological agents in some focal or invasive infections and bacteremia with a high level of mortality. Conflicting data have accumulated over the last decades regarding the extent in which these pathogens play an intrinsic role in bloodstream infections. Clinical characteristics of anaerobic bloodstream infections do not differ from bacteremia caused by other pathogens, but due to their longer generation time and rigorous growth requirements, it usually takes longer to establish the etiological diagnosis. The introduction of matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) has represented a technological revolution in microbiological diagnostics, which has allowed for the fast, accurate and reliable identification of anaerobic bacteria at a low sample cost. The purpose of this review article is to summarize the currently available literature data on the prevalence of anaerobic bacteremia in adults for physicians and clinical microbiologists and to shed some light on the complexity of this topic nowadays.

Open access
Authors: Ernst-Jürgen Finke, Wolfgang Beyer, Ulrike Loderstädt and Hagen Frickmann

Abstract

Anthrax is an infectious disease of relevance for military forces. Although spores of Bacillus anthracis obiquitously occur in soil, reports on soil-borne transmission to humans are scarce. In this narrative review, the potential of soil-borne transmission of anthrax to humans is discussed based on pathogen-specific characteristics and reports on anthrax in the course of several centuries of warfare. In theory, anthrax foci can pose a potential risk of infection to animals and humans if sufficient amounts of virulent spores are present in the soil even after an extended period of time. In praxis, however, transmissions are usually due to contacts with animal products and reported events of soil-based transmissions are scarce. In the history of warfare, even in the trenches of World War I, reported anthrax cases due to soil-contaminated wounds are virtually absent. Both the perspectives and the experience of the Western hemisphere and of former Soviet Republics are presented. Based on the accessible data as provided in the review, the transmission risk of anthrax by infections of wounds due to spore-contaminated soil is considered as very low under the most circumstance. Active historic anthrax foci may, however, still pose a risk to the health of deployed soldiers.

Open access

Abstract

The physiological colonization resistance exerted by the murine gut microbiota prevents conventional mice from Campylobacter jejuni infection. In the present study we addressed whether this also held true for Campylobacter coli. Following peroral application, C. coli as opposed to C. jejuni could stably establish within the gastrointestinal tract of conventionally colonized mice until 3 weeks post-challenge. Neither before nor after either Campylobacter application any changes in the gut microbiota composition could be observed. C. coli, but not C. jejuni challenge was associated with pronounced regenerative, but not apoptotic responses in colonic epithelia. At day 21 following C. coli versus C. jejuni application mice exhibited higher numbers of adaptive immune cells including T-lymphocytes and regulatory T-cells in the colonic mucosa and lamina propria that were accompanied by higher large intestinal interferon-γ (IFN-γ) concentrations in the former versus the latter but comparable to naive levels. Campylobacter application resulted in decreased splenic IFN-γ, tumor necrosis factor-α (TNF-α), and IL-6 concentrations, whereas IL-12p70 secretion was increased in the spleens at day 21 following C. coli application only. In either Campylobacter cohort decreased IL-10 concentrations could be measured in splenic and serum samples. In conclusion, the commensal gut microbiota prevents mice from C. jejuni, but not C. coli infection.

Open access

Abstract

Stenotrophomonas maltophilia is an aerobic, oxidase-negative and catalase-positive bacillus. S. maltophilia is a recognized opportunistic pathogen. Due to the advancements in invasive medical procedures, organ transplantation and chemotherapy of malignant illnesses, the relevance of this pathogen increased significantly. The therapy of S. maltophilia infections is challenging, as these bacteria show intrinsic resistance to multiple classes of antibiotics, the first-choice drug is sulfamethoxazole/trimethoprim. Our aim was to assess the epidemiology of S. maltophilia from various clinical samples and the characterization of resistance-levels and resistotyping of these samples over a long surveillance period. The study included S. maltophilia bacterial isolates from blood culture samples, respiratory samples and urine samples and the data for the samples, received between January 2008 until December 2017, a total of 817 S. maltophilia isolates were identified (respiratory samples n = 579, 70.9%, blood culture samples n = 175, 21.4% and urine samples n = 63, 7.7%). Levofloxacin and colistin-susceptibility rates were the highest (92.2%; n = 753), followed by tigecycline (90.5%, n = 739), the first-line agent sulfamethoxazole/trimethoprim (87.4%, n = 714), while phenotypic resistance rate was highest for amikacin (72.5% of isolates were resistant, n = 592). The clinical problem of sulfamethoxazole/trimethoprim-resistance is a complex issue, because there is no guideline available for the therapy of these infections.

Open access
Authors: Silke Dubbert, Birgit Klinkert, Michael Schimiczek, Trudy M. Wassenaar and Rudolf von Bünau

Probiotic Escherichia coli strain Nissle 1917 (EcN) has a long history of safe use. However, the recently discovered presence of a pks locus in its genome presumably producing colibactin has questioned its safety, as colibactin has been implicated in genotoxicity. Here, we assess the genotoxic potential of EcN. Metabolic products were tested in vitro by the Ames test, a mutagenicity assay developed to detect point mutation-inducing activity. Live EcN were tested by an adapted Ames test. Neither the standard nor the adapted Ames test resulted in increased numbers of revertant colonies, indicating that EcN metabolites or viable cells lacked mutagenic activity. The in vivo Mammalian Alkaline Comet Assay (the gold standard for detecting DNA-strand breaks) was used to determine potentially induced DNA-strand breaks in cells of the gastro-intestinal tract of rats orally administered with viable EcN. Bacteria were given at 109–1011 colony forming units (CFU) per animal by oral gavage on 2 consecutive days and daily for a period of 28 days to 5 rats per group. No significant differences compared to negative controls were found. These results demonstrate that EcN does not induce DNA-strand breaks and does not have any detectable genotoxic potential in the test animals.

Open access

The gastric pathogen Helicobacter pylori colonizes approximately half of the human world population. The bacterium injects the effector protein cytotoxin associated gene A (CagA) via a type-IV secretion system into host epithelial cells, where the protein becomes phosphorylated at specific EPIYA-motifs by cellular kinases. Inside the host cell, CagA can interact with over 25 different proteins in both phosphorylation-dependent and phosphorylation-independent manners, resulting in manipulation of host-cell signaling pathways. During the course of an H. pylori infection, certain host-cell proteins undergo tyrosine dephosphorylation in a CagA-dependent manner, including the actin-binding proteins cortactin and vinculin. A predominant response of intracellular CagA is the binding and activation of tyrosine phosphatase, the human Src-homology-region-2-domain-containing-phosphatase-2 (SHP2). Here, we considered the possibility that activated SHP2 might be responsible for the dephosphorylation of cortactin and vinculin. To investigate this, phosphatase inhibitor studies were performed. Additionally, a complete knockout mutant of SHP2 in AGS cells was created by CRISPR/Cas9 technology, and these cells were infected with H. pylori. However, neither the presence of an inhibitor nor the inactivation of SHP2 prevented the dephosphorylation of cortactin and vinculin upon CagA delivery. Tyrosine dephosphorylation of these proteins is therefore independent of SHP2 and instead must be caused by another, as yet unidentified, protein tyrosine phosphatase.

Open access

The terricolous species Cladonia foliacea (Cladoniaceae, lichenised Ascomycota) widely distributed in open, dry lowland steppe and rocky mountain grassland vegetation in Europe was chosen as a potential test organism for ecological experiments, since their thalli are producing cortical solar radiation-protective and UV screening pigment dibenzofuran usnic acid and medullary secondary substance depsidone fumarprotocetraric acid. Significant seasonal differences were found in the amounts of lichen secondary metabolites analysed by HPTLC and HPLC-PDA between summer and winter collected thalli in sandy grassland area in Hungary. The concentrations of usnic acid varied between 7.34 and 15.52 mg/g in summer collected samples and 13.90 and 21.61 mg/g in winter collected ones. A comparable amount (11.61±0.29 mg/g) was measured in pulverised samples. The concentrations of fumarprotocetraric acid varied between 0.60 and 3.01 mg/g in summer collected samples and 2.26 and 5.81 mg/g in winter collected thalli. A comparable amount (2.45±0.21 mg/g) was found in pulverised samples. The range of concentration values is comparable with data known from lichens. A higher amount of usnic acid is produced in winter probably to ensure sufficient protection also for summer. The fumarprotocetraric acid content of the medulla might contribute to the solar irradiation reflecting role of the pale lower surface lobes turning upwards in dry condition.

Open access

Lichenes Delicati Exsiccati Editae of little, fine, special lichens is edited in honour of Antonín Vězda (1920–2008). The fifth fascicle of the exsiccate is consisted of 20 species of lichens and lichenicolous fungi and distributed to 12 lichen herbaria of the world. Collectors are K. Buaruang, D. Kalb, K. Kalb, G. E. Lee, L. Lőkös, A. Mertens, W. Polyiam, T. Pócs, W. Saipunkaew, D. Tang, N. Varga and E. Farkas.

Open access

Between the years 2015–2018, 147 stands of Ficus carica L. was found out of cultivation in Baranya county. In 2008 presence of fig wasp (Blastophaga psenes L.) and caprificus individuals that are necessary for pollination, then for producing fertile seeds were detected in Pécs at first time. For germination tests fig seeds were collected from several different stands in Pécs and successful reproduction of the species was confirmed under in vitro conditions. According to former and recent observations (i.e. subspontaneous seedlings and/or successful in vitro germination of common fig seeds in 2010 and 2014) fig wasp may have occurred in Budapest and Máriagyűd too, at least in the last ten years. These results confirm that F. carica is an old ‘new’ casual or may be a naturalised neophyte element of the Hungarian flora. According to the new records the northernmost escaped individuals of F. carica was found at 47.475° N in the Carpathian Basin, 116.5 km N of the closest Slovenian stand in the latitudinal direction.

Open access
Authors: Zoltán Attila Köbölkuti, Klára Cseke, Attila Benke, Mátyás Báder, Attila Borovics and Róbert Németh

Introduction

Since Populus has veritable value as timber, plywood, pulp, and paper, genomic research should create the sound basis for further breeding toward desirable wood quality attributes.

Materials and methods

In this study, we addressed the need for a research methodology that initially identifies and then characterize candidate genes encoding enzymes with wood property phenotypic traits, toward the aim of developing a genomics-based breeding technology.

Results

On 23 different poplar species/hybrid samples, we successfully amplified 55 primers designed on Populus trichocarpa L. Considering the number of polymorphic sites, out of 73,206 bp, 51 SNPs and 31 indel events were found. Non-synonymous single base mutations could be detected in number of 30, 21 out of 164 sequences were the number of minimum recombination events and 41 significant pairwise comparisons between loci could be detected.

Discussion and conclusion

Our results provide a roadmap for a future association genetic study between nucleotide diversity and precise evaluation of phenotype.

Open access
Authors: Gergely Sámuel Bartha, Gergő Tóth, Péter Horváth, Eszter Kiss, Nóra Papp and Monika Kerényi

Introduction

Several Aristolochia species were used as medicinal herb across Europe and in recent years, their antimicrobial activity has also been investigated.

Materials and methods

In this study, A. clematitis was selected to evaluate the aristolochic acids I and II (AA I and AA II) concentrations and the antimicrobial activity of methanol, hexane, butanol, and ethyl acetate extracts of the root, stem, leaf, root, and fruit. AA I and AA II contents were measured by a validated high-performance liquid chromatography–ultraviolet method.

Results

Each fraction of the plant contained AA I and AA II and the root was found to have the highest contents of AA I (1.09%) and AA II (0.7454%). The minimum inhibitory concentrations of all extracts were determined by standard microdilution method. The fruit’s extracts showed the most efficient antimicrobial effect against both methicillin sensitive and resistant Staphylococcus aureus strains.

Conclusion

Correlation between the AA I and AA II concentrations and the antimicrobial effect was not found.

Open access

Due to its overall environmental impact, the residual dye in the wastewater from the synthetic dye manufacturing and textile industries is a global concern. The discharge contains a high content of pigments and other additives, possessing complex structures. As per the requirement for dyed clothing, dyestuff in the effluent is less susceptible to acids, bases, and oxygen. Thus, conventional physical and chemical methods are not always efficient in degrading the dyes. Some microorganisms growing in an area affected with textile effluent have the capability to utilize the dyes as a source of carbon or nitrogen or both. As a very clean, inexpensive, and sufficient alternative, bioremediation of textile wastewater using these microorganisms has gained major popularity. This review primarily centers the contribution of bacteria in this sector and the isolation of such bacteria from textile effluent. A secondary focus is discussing the factors which influence the performance by different bacteria.

Open access
Authors: Rubina Tu¨nde Szabó, Mária Kovács-Weber, Márta Erdélyi, Krisztián Balogh, Natasa Fazekas, Ákos Horváth, Miklós Mézes and Balázs Kovács

Background and aims

The aim of this study was to verify that the comet assay can be used to investigate the DNA damaging effects of T-2 and HT-2 toxins in the liver of broiler chickens. The comet assay is a favorable genotoxic analysis because it is cheap, simple, and can be used in many organisms and different tissues.

Materials and methods

Male broiler chickens were fed with T-2/HT-2 toxins-contaminated diet for 14 days. The comet assay was successfully adapted to chicken liver cells, and the DNA damage was determined by a decrease in the comet parameter (DNA % in the tail) in the experimental groups.

Results

The method of evaluation was found to be critical because DNA damage could not be detected exactly using the CometScore software, due to inaccurate separation of head and comet. However, this problem can be solved by visual evaluation.

Conclusion

In the case of the visual evaluation, each toxin-treated group differed significantly from the control group, indicating that the assay can be useful for the assessment of primary DNA damage caused by T-2/HT-2 toxins.

Open access

Introduction

In this study, we analyzed gynandromorphs with female terminalia, to dissect mating-related female behaviors in Drosophila.

Materials and methods

We used gynandromorphs, experimentally modified wild-type (Oregon-R) females, and mutant females that lacked different components of the female reproductive apparatus.

Results

Many of the gynandromorphs mated but did not expel the mating plug (MP). Some of these – with thousands of sperm in the uterus – failed to take up sperm into the storage organs. There were gynandromorphs that stored plenty of sperm but failed to release them to fertilize eggs. Expelling the MP, sperm uptake into the storage organs, and the release of stored sperm along egg production are separate steps occurring during Drosophila female fertility. Cuticle landmarks of the gynandromorphs revealed that while the nerve foci that control MP expelling and also those that control sperm uptake reside in the abdominal, the sperm release foci derive from the thoracic region of the blastoderm.

Discussion and conclusion

The gynandromorph study is confirmed by analyses of (a) mutations that cause female sterility: Fs(3)Avar (preventing egg deposition), Tm2gs (removing germline cells), and iab-4DB (eliminating gonad formation) and (b) by experimentally manipulated wild-type females: decapitated or cut through ventral nerve cord.

Open access
Authors: F. Tóth, Franciska Tóthné Bogdányi, Renáta Petrikovszki, Anita Gódor, M. Zalai, B. Bálint, P. Sunder and A. Myrta

The effectiveness of dimethyl disulfide (DMDS) to control root-knot nematodes (Meloidogyne spp.) and weeds was tested for the first time in Hungary in two consecutive protected cucumber crops with application made only before the first crop. The treatments were Accolade EC (DMDS 94.1%) at 400 l/ha applied by driplines, Nemathorin 10 G (fosthiazate) at 30 kg/ha, and an untreated control. During the first cucumber cycle vigour-index, yield, root-gall index, Meloidogyne juveniles in the soil and germination of weeds were evaluated. All considered parameters were significantly improved by using DMDS compared respectively to the chemical standard and untreated control: (i) vigour-index of 7.0, 4.3 and 3.6; (ii) cumulative yield/sample of 45.1 kg, 30.9 kg, and 16.6 kg; root-gall index (RGI) of 1.2, 4.9, and 5.9; (iii) M. incognita J2/25 g soil of 0.25, 48.5 and 78.0, and (iv) number of weed seedlings/sample in the 20–30 cm soil profile of 1.1, 2.6, and 4.2. During the second cucumber crop, only root-gall index was evaluated. Results showed that a single DMDS treatment applied before the first crop had a prolonged beneficial effect on the following crop. In the second crop cycle, root gall indices were 5.58, 9.18, and 8.44 for DMDS treated plots, chemical control and untreated control, respectively.

Open access
Authors: Elisabetta Gerace, Vincenzo Di Marco Lo Presti and Carmelo Biondo

Cryptosporidium is a protozoan that infects a wide variety of vertebrates, including humans, causing acute gastroenteritis. The disease manifests with abdominal pain and diarrhea similar to that of choleric infection. In the immunocompromised hosts, the parasite causes prolonged infections that can also be fatal. For this reason, cryptosporidiosis is considered one of riskiest opportunistic infections for patients with acquired immunodeficiency syndrome. The best way to control the infection in these patients is setting up sensitive and specific diagnostic tests for epidemiological surveillance and morbidity reduction. Here, we summarized the general aspects of Cryptosporidium infection focusing on available diagnostic tools used for the diagnosis of cryptosporidiosis. Molecular methods currently available for its detection and progress in the development of new diagnostics for cryptosporidiosis are also discussed.

Open access

Few researches address the compatibility of organic mulching and entomopathogenic (EPN) and slug-parasitic (SPN) nematodes, although organic mulching may provide favourable conditions for these beneficial organisms. Our aim was to examine the effect of different concentrations (0.1, 0.5, 1 and 5%) of aqueous extracts of green waste compost, the dry leaf litters of the common walnut (Juglans regia) and Norway maple (Acer platanoides) on EPN (Heterorhabditis bacteriophora, Steinernema carpocapsae, Steinernema feltiae, Steinernema kraussei) and SPN (Phasmarhabditis hermaphrodita) species. Experiments were set up in 96-well, flat-bottom microplates. After a 24-hour exposure time, the number of dead animals was counted under a transmission microscope. Green waste compost extracts caused quite low or no mortality in case of all examined species. Mortality caused by the 5% Norway maple leaf litter extract was moderate (34.6%) in the case of S. carpocapsae juveniles, while 100% of juveniles of other species died. The highest (5%) concentration of the common walnut leaf litter extract caused 100% mortality in all species. As a conclusion, green waste compost mulch seems to be more compatible with EPN and SPN species than common walnut or Norway maple leaf litter mulch.

Open access

Abstract

In gravel pits, a mosaic of habitats with various environmental conditions created during mining has a great potential for persistence of many species. We focused on such a mosaic in a gravel pit surrounded by agricultural landscape. We investigated which habitats within sludge deposits in different successional stages (from bare sands to secondary forest) and agriculturally reclaimed area enhanced diversity, species richness and abundance of carabids and supported occurrence of threatened species. Since some of these habitats were extensively managed while others were invaded by the alien plant Solidago gigantea, we also tested the effect of management and the cover of S. gigantea on carabid assemblages. We found a gradient in carabid assemblages from psammophilous ones in bare sandy soils towards similar assemblages in plots with well-developed vegetation cover. Here, carabid assemblages were represented predominantly by common species of agricultural and forest lands without higher habitat requirements. Contrarily, plots with bare sand could serve as a refuge for rare psammophilous carabid species, which cannot occur in surrounding landscape due to vanished suitable habitats. Therefore, keeping some of habitats in early plant successional states is important for maintaining habitat mosaic and for persistence of such species as well. Management of grasslands and cover of S. gigantea had no effect on carabid assemblage. We presume that carabids were likely more affected by vegetation structure and density than species composition.

Open access
Authors: Patricia Patricio, José Artur Paiva and Luís Miguel Borrego

Sepsis leads to a systemic immune response, and despite the progress of modern medicine, it is still responsible for a high mortality rate.

The immune response to sepsis is dependent on the innate and adaptive immune systems. The first line is the innate system, which requires complex and multiple pathways in order to eliminate the invading threats. The adaptive responses start after the innate response. The cell-mediated arm of CD4+ and CD8+ T and B cells is the main responsible for this response.

A coordinated cytokine response is essential for the host immune response. A dysregulated response can lead to a hyperinflammatory condition (cytokine storm). This hyperinflammation leads to neutrophils activation and may also lead to organ dysfunction. An imbalance of this response can increase the anti-inflammatory response, leading to compensatory anti-inflammatory response syndrome (CARS), persistent inflammation-immunsupression, catabolism syndrome (PICS), and, above all, an immune paralysis stat.

This immune paralysis leads to opportunistic infections, Candida species being one of the emerging microorganisms involved. The host immune response is different for bacterial or Candida sepsis.

Immune responses for bacterial and Candida sepsis are described in this paper.

Open access
Authors: N. von Allmen, K. Gorzelniak, O. Liesenfeld, M. Njoya, J. Duncan, E. M. Marlowe, T. Hartel, A. Knaust, B. Hoppe and M. Walter

Rapid detection of methicillin-resistant Staphylococcus aureus (MRSA) colonization status facilitates isolation and decolonization and reduces MRSA infections. Liquid but not dry swabs allow fully automated detection methods. However, the accuracy of culture and polymerase chain reaction (PCR) using liquid and dry swabs has not been analyzed. We compared different swab collection systems for routine nasal–throat MRSA screening in patients admitted to a tertiary care trauma center in Germany. Over 3 consecutive months, dry swabs (month 1), ESwabs (month 2), or MSwabs (month 3) were processed using Cepheid GeneXpert, Roche cobas and BD-MAX™ MRSA tests compared to chromogenic culture. Among 1680 subjects, the MRSA detection rate using PCR methods did not differ significantly between dry swabs, ESwab, and MSwab (6.0%, 6.2%, and 5.3%, respectively). Detection rates using chromogenic culture were 2.9%, 3.9%, and 1.9%, using dry, ESwab, and MSwab, respectively. Using chromogenic culture as the “gold standard”, negative predictive values for the PCR tests ranged from 99.2–100%, and positive predictive values from 33.3–54.8%. Thus, efficient and accurate MRSA screening can be achieved using dry, as well as liquid E- or MSwab, collection systems. Specimen collection using ESwab or MSwab facilitates efficient processing for chromogenic culture in full laboratory automation while also allowing molecular testing in automated PCR systems.

Open access
Authors: Hagen Frickmann, Andreas Hahn, Stefan Berlec, Johannes Ulrich, Moritz Jansson, Norbert Georg Schwarz, Philipp Warnke and Andreas Podbielski

Introduction: Escherichia coli and Staphylococcus aureus are important causes of severe diseases like blood stream infections. This study comparatively assessed potential differences in their impact on disease severity in local and systemic infections.

Methods: Over a 5-year interval, patients in whom either E. coli or S. aureus was detected in superficial or primary sterile compartments were assessed for the primary endpoint death during hospital stay and the secondary endpoints duration of hospital stay and infectious disease as the main diagnosis.

Results: Significance was achieved for the impacts as follows: Superficial infection with S. aureus was associated with an odds ratio of 0.27 regarding the risk of death and of 1.42 regarding infectious disease as main diagnosis. Superficial infection with E. coli was associated with a reduced duration of hospital stay by −2.46 days and a reduced odds ratio of infectious diseases as main diagnosis of 0.04. The hospital stay of patients with E. coli was increased due to third-generation cephalosporin and ciprofloxacin resistance, and in the case of patients with S. aureus due to tetracycline and fusidic acid resistance.

Conclusions: Reduced disease severity of superficial infections due to both E. coli and S. aureus and resistance-driven prolonged stays in hospital were confirmed, while other outcome parameters were comparable.

Open access

Abstract

In this paper, we want to support the idea of using a family of indices of similarity, that we call the Simpson's family indices or nestedness-based similarity functions (NBSF) for comparing operational geographic units (OGUs) (phytosociological relevés, animal traps, watersheds, administrative units, industrial areas, islands etc.). In these cases, similarity-dissimilarity depends, in addition to factors that induce replacement, also on factors that produce reduction or increment in the number of features within the same typology of OGUs (e.g., extent, reduction of fertility, anthropogenic pressure etc.). To keep into consideration this aspect, the indices are defined to be equal to 1 when the OGUs are completely nested. The results of the application to four simulated data sets prove that, when the data set does not show clear nested pattern, the use of NBSF produces results similar to the nestedness-free similarity functions, however since NBSF clearly detect nested situations, we should prefer their use in the circumstances where we think important to put in evidence nestedness. In conclusion, we support the idea of using both types of indices in order to improve the knowledge about the structure of any data set.

Open access

Introduction: The study was performed to estimate the prevalence and determinants of occurrence of sexually transmitted infections (STIs) in paratroopers and navy soldiers by anonymously analyzing medical records from the medical departments of two large German barracks in order to assess the need for medical STI prevention.

Methods: Medical records from 80 paratroopers and 80 navy soldiers were screened for records of STI. Results were anonymously collected next to information on risk factors, as well as diagnostic and therapeutic management, and comparatively assessed.

Results: Proportions of suspected STIs were 17.5% and 20%, and proportions of diagnosed STIs were 13.9% and 11.3% for paratroopers and navy soldiers, respectively. Chlamydia trachomatis, human papillomavirus, and genital scabies were observed in paratroopers and navy soldiers, while Gardnerella vaginalis, herpes simplex virus, Molluscum contagiosum virus, Neisseria gonorrhoeae, and Trichomonas vaginalis were additionally identified in navy soldiers.

Conclusions: Although clinical hints for STIs were frequently observed, clinical management was usually restricted to syndrome-based antibiotic treatment without detailed diagnostic workup, leaving room for procedural improvement. Ongoing need for medical STI prevention in the military could be confirmed.

Open access

Abstract

We briefly complement Endrédi et al. (2019) forum paper from terrestrial animal ecological points of view. We discuss the origins of trait-based approach, challenges of trait classifications, and we provide an example of a commonly used trait, body size.

Open access

Antimicrobial multidrug-resistance (MDR) constitutes an emerging threat to global health and makes the effective prevention and treatment of many, particularly severe infections challenging, if not impossible. Many antibiotic classes have lost antimicrobial efficacy against a plethora of infectious agents including bacterial species due to microbial acquisition of distinct resistance genes. Hence, the development of novel anti-infectious intervention strategies including antibiotic-independent approaches is urgently needed. Vitamins such as vitamin D and vitamin D derivates might be such promising molecular candidates to combat infections caused by bacteria including MDR strains. Using the Pubmed database, we therefore performed an in-depth literature survey, searching for publications on the antimicrobial effect of vitamin D directed against bacteria including MDR strains. In vitro and clinical studies between 2009 and 2019 revealed that vitamin D does, in fact, possess antimicrobial properties against both Gram-positive and Gram-negative bacterial species, whereas conflicting results could be obtained from in vivo studies. Taken together, the potential anti-infectious effects for the antibiotic-independent application of vitamin D and/or an adjunct therapy in combination with antibiotic compounds directed against infectious diseases such as tuberculosis, H. pylori infections, or skin diseases, for instance, should be considered and further investigated in more detail.

Open access

This study aimed at evaluating in outpatients an algorithm for the laboratory diagnosis of Clostridioides (Clostridium) difficile infection (CDI), i.e., enzyme immunoassays (EIAs) detecting bacterial glutamate dehydrogenase (GDH) and toxin A/B, followed by polymerase chain reaction (PCR) analyses of samples with discordant EIA results.

In total, 9802 examinations of stool samples by GDH and toxin EIAs performed in 7263 outpatients and 488 inpatients were analyzed retrospectively. Samples with discordant EIA results had been tested by a commercially available PCR assay detecting genes of the C. difficile-specific triose phosphate isomerase (tpi) and toxin B (tcdB).

Concordant EIA results (686 C. difficile-positive, 8121 negative) were observed for 8807 (89.8%; 95% CI, 89.2–90.4%) samples. Of 958 samples with discordant EIA results, 895 were analyzed using PCR and 580 of 854 GDH-positive/borderline, toxin-negative samples (67.9%; 95% CI, 64.7–71.0%) were positive for tpi and tcdB, while 274 samples (32.1%; 95% CI, 29.0–35.3%) were tcdB-negative. In contrast, 35 of 41 GDH-negative, toxin-positive/borderline samples (85.4%; 95% CI, 71.2–93.5%) were tcdB-negative. Still, 6 samples (14.6%; 95% CI, 6.5–28.8%) yielded positive PCR results for both genes.

In conclusion, around 90% of the samples were analyzed appropriately by only applying EIAs. Approximately one third of the PCR-analyzed samples were tcdB-negative; thus, patients most likely did not require CDI treatment.

Open access

Glyphosate (N-(phosphonomethyl)glycine) is the most-used herbicide worldwide. Many studies in the past have shown that residues of the herbicide can be found in many cultivated plants, including those used as livestock feed. Sensitivity to glyphosate varies with bacteria, particularly those residing in the intestine, where microbiota is exposed to glyphosate residues. Therefore, less susceptible pathogenic isolates could have a distinct advantage compared to more sensitive commensal isolates, probably leading to dysbiosis.

To determine whether the ruminal growth and survival of pathogenic Escherichia coli or Salmonella serovar Typhimurium are higher when glyphosate residues are present in the feed, an in vitro fermentation trial with a “Rumen Simulation System” (RUSITEC) and a glyphosate-containing commercial formulation was performed.

Colony forming units of E. coli and Salmonella ser. Typhimurium decreased steadily in all fermenters, regardless of the herbicide application. Minimum inhibitory concentrations of the studied Salmonella and E. coli strains did not change, and antibiotic susceptibility varied only slightly but independent of the glyphosate application.

Overall, application of the glyphosate-containing formulation in a worst-case concentration of 10 mg/L neither increased the abundance for the tested E. coli and Salmonella strain in the in vitro fermentation system, nor promoted resistance to glyphosate or antibiotics.

Open access
Authors: Soraya Mousavi, Stefan Bereswill and Markus M. Heimesaat

Humans have lost their vitamin C-synthesizing capacities during evolution. Therefore, the uptake of this essential compound from external sources is mandatory in order to prevent vitamin C-deficient conditions resulting in severe morbidities such as scurvy. The potent antioxidant, immunomodulatory, and antiinfectious effects of vitamin C are known since the 1930s. We here (i) review the impact of vitamin C on innate and adaptive immune functions, (ii) provide an overview of its antimicrobial, antibacterial, antiviral, antiparasitic, and antifungal properties, and finally, (iii) discuss vitamin C as an adjunct treatment option for the combat of human infections by bacteria, particularly by emerging multidrug-resistant species.

Open access
Authors: Cosme Alvarado-Esquivel, Ángel Osvaldo Alvarado-Félix and Gustavo Alexis Alvarado-Félix

The epidemiology of Toxocara infection in rural Mexico is largely unknown. Therefore, we sought to determine the seroprevalence of Toxocara infection in rural people in a northern Mexican state. We performed a cross-sectional seroprevalence study of 641 people living in rural Durango State including 282 subjects of the general population, 214 subjects of Huichol ethnicity, and 145 subjects of Mennonite ethnicity. Sera of participants were analyzed for the presence of anti-Toxocara immunoglobulin G (IgG) antibodies using a commercially available enzyme immunoassay. Three (0.5%) of the 641 subjects tested were positive for anti-Toxocara IgG antibodies. Of the 3 Toxocara seropositive subjects, two were females, aged 19 and 39 years, and one was male, aged 59 years. They had contacted with dogs, cleaned cat excrement, consumed unwashed raw fruits, contacted soil, or lived in a house with soil floors. Seroprevalence of Toxocara infection was similar among the 3 groups of population studied: 0.4% for the general population, 0.9% for Huicholes, and 0.0% for Mennonites (P = 0.41). In conclusion, the Toxocara seroprevalence found in subjects in rural Durango is low as compared with those reported in people from rural areas in other countries.

Open access

Zoopsidella grahamii sp. nov., related to the Australasian Z. caledonica, is described from the Andes of Central Peru (Oxapampa Province) and southern Ecuador. It is distinguished from Z. caledonica by the smaller plant size, much lower number of lobe cells and different leaf shape, and by the much more elongate perianth mouth lobes consisting of a row of 6-7 narrowly rectangular cells. Riccardia gradsteinii sp. nov., from the same general area in Peru as Z. grahamii, is unique among all dendroid species of the genus by the broad, frilled wings of the main axis, being split into complicatedly bent and strongly crispate scales.

Open access
Authors: T. Pócs, N.-K.-T. Tram, Q. He, T. Katagiri and T.-T. Luong

After the examination of the Cryptogam collection in the Herbarium of the University of Science, Vietnam National University Ho Chi Minh City (PHH), 25 species proved to be new to Vietnam, including one hornwort and 24 liverworts. Among them, four genera: Denotarisia Grolle, Gongylanthus Nees, Leiomitra Lindb. and Lepicolea Dumort. are new records for the country. Diagnostic characters and illustrations are given for some taxa, as well as locality notes and habitat descriptions are provided for each collecting area.

Open access
Authors: Isabel Stephany-Brassesco, Stefan Bereswill, Markus M. Heimesaat and Matthias F. Melzig

Antibiotic resistance of Streptococcus pneumoniae has risen to worrying levels in the past few decades worldwide, and subsequently, effective treatment of respiratory tract infections has become even more challenging. While the need to develop new strategies to combat bacterial infections is urgent, novel antibiotic compounds are no longer a priority of the pharmaceutical industry. However, resistance-modifying agents can alleviate the spread of antibiotic resistance and render existing antibiotics effective again. In the present study, we aimed to determine the combinatory antimicrobial effects of the commercial herbal product Cefabronchin® and antibiotic compounds, such as amoxicillin and clarithromycin, on 6 clinical isolates of S. pneumoniae. Therefore, the minimal inhibitory concentration (MIC) of each agent before and after adding Cefabronchin® at different concentrations was determined by applying the checkerboard method. Sub-inhibitory concentrations of the added Cefabronchin® were found to reduce the MIC down to between 3.4% and 29.2% of the amoxicillin MIC and down to between 10.4% and 45.8% of the clarithromycin MIC in all 6 strains. In conclusion, this study provides evidence for the improved antimicrobial effects of commonly used antibiotics in combination with Cefabronchin® in order to combat infections with antibiotic-resistant S. pneumoniae strains.

Open access

Abstract

Biofouling is predicted to increase in the course of global warming, making the study and monitoring of its ecological and economic consequences of great importance. The present study describes, for the first time, recruitment and successional patterns of fouling communities in the Caspian Sea. During one year, short-term panels (STP; replaced every 2 months) and long-term panels (LTP; retrieved after 4, 8 and 12 months) were deployed in the Western Iranian coast of the Caspian Sea. Temporal trends in both sets of panels were evaluated through Generalized Additive Models and discussed in light of the environmental variables registered in each sampling event. Recruitment and successional patterns observed at the community level were mainly driven by barnacles and bryozoans, the dominant taxa over the entire sampling period. Panel coverage, biomass and inorganic to organic matter ratio exhibited clear seasonal patterns in STP, following temperature and chlorophyll a trends. In LTP, coverage and biomass increased over the study period, while the inorganic to organic matter ratio peaked in summer and decreased during autumn and winter months. These results represent a baseline for future studies on biofouling communities in the Caspian Sea, where this topic has been completely neglected.

Open access
Authors: R. Olmo Gilabert, A. F. Navia, G. De La Cruz-Agüero, J. C. Molinero, U. Sommer and M. Scotti

Abstract

Anthropic activities impact ecosystems worldwide thus contributing to the rapid erosion of biodiversity. The failure of traditional strategies targeting single species highlighted ecosystems as the most suitable scale to plan biodiversity management. Network analysis represents an ideal tool to model interactions in ecosystems and centrality indices have been extensively applied to quantify the structural and functional importance of species in food webs. However, many network studies fail in deciphering the ecological mechanisms that lead some species to occupy the most central positions in food webs. To address this question, we built a high-resolution food web of the Gulf of California and quantified species position using 15 centrality indices and the trophic level. We then modelled the values of each index as a function of traits and other attributes (e.g., habitat). We found that body size and mobility are the best predictors of indices that characterize species importance at local, meso- and global scale, especially in presence of data accounting for energy direction. This result extends previous findings that illustrated how a restricted set of traitaxes can predict whether two species interact in food webs. In particular, we show that traits can also help understanding the way species are affected by and mediate indirect effects. The traits allow focusing on the processes that shape the food web, rather than providing case-specific indications as the taxonomy-based approach. We suggest that future network studies should consider the traits to explicitly identify the causal relationships that link anthropic impacts to role changes of species in food webs.

Open access
Authors: Ralf Ignatius, Christiane Berg, Chris Weiland, Angela Darmer, Thilo Wenzel, Marion Lorenz, Jörg Fuhrmann and Michael Müller

Stool antigen tests are recommended for the diagnosis of Helicobacter pylori infection. Here, we compared two novel assays, i.e., one enzyme immunoassay (EIA) and one immunochromatography assay (ICA), with a chemiluminescence immunoassay (CLIA) that had previously been compared with rapid urease test, histology, and urea breath test. Two hundred sixty-six frozen stool samples with defined CLIA results (42 positives, 219 negatives, and 5 samples with borderline results) collected between January and May 2018 were thawed and immediately tested by EIA, ICA, and CLIA.

In 248 samples with repeatedly positive/negative CLIA results, EIA and ICA were positive for 40 and 37 of 41 CLIA-positive samples and yielded negative results for 206 and 201 of 207 CLIA-negative samples, respectively. There was a high positive percent agreement (EIA, 97.6%; 95% confidence interval (95% CI), 86.3–100%; ICA, 90.2%; 95% CI, 76.9–96.7%), as well as a negative percent agreement between the assays (EIA, 99.5%; 95% CI, 97.0–100%; ICA, 97.1%; 95% CI, 93.7–98.8%). This was further supported by kappa values indicating very good agreement (CLIA vs. EIA, 0.971; CLIA vs. ICA, 0.857). In conclusion, both EIA and ICA comprise valuable assays for the detection of H. pylori antigen in stool samples.

Open access

Campylobacter jejuni and Campylobacter coli are among the leading causes of gastroenteritis in humans worldwide, particularly in Africa. Poultry remains a major source of Campylobacter species and a vector of transmission to humans.

This pilot study was aimed at isolating and determining the antibiotic susceptibility profiles of Campylobacter spp. from fresh poultry droppings collected from poultry farms in Lagos State, Nigeria. Susceptibility was assessed using the CLSI standards.

Standard microbiological methods were used in isolation, identification, and characterization of Campylobacter spp. Isolates were subjected to antibiotic susceptibility testing by the disk diffusion method.

Of the 150 poultry droppings analyzed, 8 (5.3%) harbored Campylobacter spp. All isolates proved to be C. coli since they were all negative for the hip gene. A percentage of 100% showed resistance to nalidixic acid, chloramphenicol, cloxacillin, and streptomycin. While 87.5% were susceptible to amoxicillin and amoxicillin/clavulanic acid, 62.5% were susceptible to tetracycline. Surprisingly, 62.5% of C. coli had decreased (intermediate) susceptibility to erythromycin.

Although there was a low prevalence of C. coli from poultry in this study, the presence of antibiotic resistant strains circulating the food chain could result in treatment failures and difficulty in case management if involved in infections of humans.

Open access
Authors: Abdelaziz Ed-Dra, Fouzia Rhazi Filali, Slimane Khayi, Said Oulghazi, Brahim Bouchrif, Abdellah El Allaoui, Bouchra Ouhmidou and Mohieddine Moumni

Salmonella is a major cause of morbidity and mortality in humans worldwide, and the infection with multidrug-resistant strains can cause severe diseases. This study was designed to evaluate the antimicrobial resistance, to detect the virulence genes, and to study the genetic diversity of isolated Salmonella strains using 16S rRNA sequences. For this, 34 Salmonella strains isolated from sausages were identified using biochemical and serological methods. Molecular tools were used to evaluate the presence of virulence genes (orgA, sitC, sipB, spiA, iroN, and sifA) using simplex and multiplex polymerase chain reaction (PCR) and to sequence 16S rRNA genes for phylogenetic analysis. The susceptibility to 24 selected antibiotics was also studied. The results of this study showed that all isolated Salmonella were positive for targeted virulence genes and were resistant to at least one antibiotic. However, the multidrug resistance was observed in 44% of isolated strains. The phylogenetic analysis of 16S rRNA sequences highlighted that Salmonella isolates were divided into 3 clusters and 3 sub-clusters, with a ≥98% similarity to Salmonella enterica species. From this study, we conclude that sausages are considered as a potential source of Salmonella, which could be a major risk to public health.

Open access
Authors: E. Sapi, K. Gupta, K. Wawrzeniak, G. Gaur, J. Torres, K. Filush, A. Melillo and B. Zelger

Our research group has recently shown that Borrelia burgdorferi, the Lyme disease bacterium, is capable of forming biofilms in Borrelia-infected human skin lesions called Borrelia lymphocytoma (BL). Biofilm structures often contain multiple organisms in a symbiotic relationship, with the goal of providing shelter from environmental stressors such as antimicrobial agents. Because multiple co-infections are common in Lyme disease, the main questions of this study were whether BL tissues contained other pathogenic species and/or whether there is any co-existence with Borrelia biofilms. Recent reports suggested Chlamydia-like organisms in ticks and Borrelia-infected human skin tissues; therefore, Chlamydia-specific polymerase chain reaction (PCR) analyses were performed in Borrelia-positive BL tissues. Analyses of the sequence of the positive PCR bands revealed that Chlamydia spp. DNAs are indeed present in these tissues, and their sequences have the best identity match to Chlamydophila pneumoniae and Chlamydia trachomatis. Fluorescent immunohistochemical and in situ hybridization methods demonstrated the presence of Chlamydia antigen and DNA in 84% of Borrelia biofilms. Confocal microscopy revealed that Chlamydia locates in the center of Borrelia biofilms, and together, they form a well-organized mixed pathogenic structure. In summary, our study is the first to show BorreliaChlamydia mixed biofilms in infected human skin tissues, which raises the questions of whether these human pathogens have developed a symbiotic relationship for their mutual survival.

Open access
Authors: Kálmán Czeibert, Attila Andics, Örs Petneházy and Enikő Kubinyi

Background and aims

Dogs have recently become an important model species for comparative social and cognitive neuroscience. Brain template-related label maps are essential for functional magnetic resonance imaging (fMRI) data analysis, to localize neural responses. In this study, we present a detailed, individual-based, T1-weighted MRI-based brain label map used in dog neuroimaging analysis.

Methods

A typical, medium-headed dog (a 7.5-year-old male Golden Retriever) was selected from a cohort of 22 dogs, based on brain morphology (shape, size, and gyral pattern), to serve as the template for a label map.

Results

Eighty-six 3-dimensional labels were created to highlight the main cortical (cerebral gyri on the lateral and medial side) and subcortical (thalamus, caudate nucleus, amygdala, and hippocampus) structures of the prosencephalon and diencephalon, and further main parts of brainstem (mesencephalon and rhombencephalon).

Discussion

Importantly, this label map is (a) considerably more detailed than any available dog brain template; (b) it is easy to use with freeware and commercial neuroimaging software for MRI and fMRI analysis; and (c) it can be registered to other existing templates, including a recent average-based dog brain template. Using the coordinate system and label map proposed here can enhance precision and standard localization during future canine neuroimaging studies.

Open access
Authors: Matthias F. Emele, Matti Karg, Helmut Hotzel, Linda Graaf-van Bloois, Uwe Groß, Oliver Bader and Andreas E. Zautner

Campylobacter fetus is a causative agent of intestinal illness and, occasionally, severe systemic infections and meningitis. C. fetus currently comprises three subspecies: C. fetus subspecies fetus (Cff), C. fetus subspecies venerealis (Cfv), and C. fetus subspecies testudinum (Cft). Cff and Cfv are primarily associated with mammals whereas Cft is associated with reptiles.

To offer an alternative to laborious sequence-based techniques such as multilocus sequence typing (MLST) and polymerase chain reaction (PCR)-ribotyping for this species, the purpose of the study was to develop a typing scheme based on proteotyping.

In total, 41 representative C. fetus strains were analyzed by intact cell mass spectrometry and compared to MLST results. Biomarkers detected in the mass spectrum of C. fetus subsp. fetus reference strain LMG 6442 (NCTC 10842) as well as corresponding isoforms were associated with the respective amino acid sequences and added to the C. fetus proteotyping scheme.

In combination, the 9 identified biomarkers allow the differentiation of Cft subspecies strains from Cff and Cfv subspecies strains. Biomarkers to distinguish between Cff and Cfv were not found. The results of the study show the potential of proteotyping to differentiate different subspecies, but also the limitations of the method.

Open access
Authors: Ivaylo Borislavov Iotchev, Anna Egerer, Serena Grafe, András Adorján and Enikő Kubinyi

Introduction

The aim of this study was to explore spontaneous social interactions between dyads of unfamiliar adult dogs. Although intraspecific encounters are frequent events in the life of pet dogs, the factors that might influence encounters, such as sex, dyad composition, reproductive status, age, and state of cohabitation (keeping the dogs singly or in groups), remained unexplored.

Methods

In this study, we assigned unfamiliar, non-aggressive dogs to three types of dyads defined by sex and size. We observed their unrestrained, spontaneous behaviors in an unfamiliar dog park, where only the two dogs, the owners, and experimenter were present.

Results

We found that the dogs, on average, spent only 17% of the time (less than 1 min) in proximity. Sex, dyad composition, reproductive status, and age influenced different aspects of the interactions in dyads. Female dogs were more likely to initiate the first contact in their dyad but later approached the partner less frequently, were less likely to move apart, and displayed less scent marking. Following and moving apart were more frequent in male–male interactions. Neutered dogs spent more time following the other dog and sniffed other dogs more frequently. The time companion dogs spent in proximity and number of approaches decreased with age.

Conclusion

The study provides guidance for dog owners about the outcomes of intraspecific encounters based on the dog’s age, sex, and reproductive status, as well as the sex of the interacting partner.

Open access

Introduction

Converging evidence suggests that the presence of (attentive) others has a positive effect on people’s propensity to conform to social rules. It is also increasingly accepted that pet dogs are promising test subjects to study non-human analogues of “audience effect.” This study investigates whether dogs show a tendency to change their behavior according to the visual attention of familiar and unfamiliar human partners in a situation in which human partners disallowed the dog from eating a piece of food.

Methods

Dogs (n = 64) participated in two observational conditions (Attentive Owner and Attentive Experimenter) and a control condition in which both human participants engaged in distracting activity.

Results

The results showed that the identity of the attentive or inattentive partner has little relevance to the dogs’ gazing behavior (i.e., head orientation toward the different partners and the food) and their decisions about breaking or following the rule. This is in line with previous studies suggesting that the presence of the owner predominantly determines the dogs’ responses to such situations.

Discussion

Further analysis of dogs responding differently to the obedience challenge showed marked differences in the role of the “audience effect” might play in modulating “fully obedient,” “ignorer,” and “hesitating” dogs’ gazing behavior. These findings point to the context-dependent nature of the audience effect in dogs and highlight the importance of frequently ignored individual differences in dogs’ tendency to conform to the situational rules.

Open access

The addition of synthetic eugenol and benzyl acetate to the known floral chemical and moth attractant phenylacetaldehyde synergized attraction of the silver Y moth Autographa gamma, an important noctuid pest. Traps baited with the ternary blend caught 2 to 6 times more A. gamma moths than traps baited with phenylac-etaldehyde alone. Both female and male moths were attracted, supposedly in the natural sex ratio of the local population. More A. gamma were caught when the blend was formulated in dispenser types with higher release rates. Traps baited with the ternary lure in polyethylene bag dispensers caught 20% to 34% as many moths as were caught in traps baited with synthetic sex pheromone, suggesting that this improved bisexual lure could be efficient enough to yield a new tool for detection and monitoring of female and male A. gamma, for more reliable plant protection decisions.

The same ternary lure also improved trap catches of moths over phenylacetaldehyde alone for the plusiinae pests MacDunnoughia confusa (in Europe) and Autographa californica (in North America) and for the Noctuinae cutworm Xestia c-nigrum (in North America).

Open access
Authors: Anna Gábor, Noémi Kaszás, Ádám Miklósi, Tamás Faragó and Attila Andics

Background and aims

Conspecific individual recognition using vocal cues has been shown in a wide range of species but there is no published evidence that dogs are able to recognize their owner based on his/her voice alone (interspecific individual recognition).

Methods

In our test, dogs had to rely on vocal cues to find their hidden owner in a two-way choice task. From behind an opaque screen, both the owner and a control person uttered neutral speech (reading sentences from a receipt) before the dogs were allowed to make their choice. Correct choices were reinforced by food and by verbal praise.

Results

During the six-choice trials, dogs chose their owner’s voice significantly more often than the control person’s voice. There was no effect of learning throughout the trials, and dogs did not show side preference.

Discussion

Thus, dogs are able to discriminate interspecific voices, suggesting that they are able to identify their owner based on vocal cues alone. This experimental design allows exploration of the role of individual acoustic parameters (such as fundamental frequency) in voice discrimination.

Open access

Correlations between juvenile wheat root traits, and grain yield and yield component traits under optimal field conditions have previously been reported in some conditions. The aim of this study was to test the hypothesis that juvenile wheat root traits correlate with yield, yield components and grain mineral composition traits under a range of soil environments in India. A diverse panel of 36 Indian wheat genotypes were grown for ten days in ‘pouch and wick’ high-throughput phenotyping (HTP) system (20 replicates). Correlations between juvenile root architecture traits, including primary and lateral root length, and grain yield, yield components and grain mineral composition traits were determined, using field data from previously published experiments at six sites in India. Only a limited number of juvenile root traits correlated with grain yield (GYD), yield components, and grain mineral composition traits. A narrow root angle, potentially representing a ‘steep’ phenotype, was associated with increased GYD and harvest index (HI) averaged across sites and years. Length related root traits were not correlated with GYD or HI at most sites, however, the total length of lateral roots and lateral root number correlated with GYD at a sodic site of pH 9.5. The total length of lateral roots (TLLR) correlated with grain zinc (Zn) concentration at one site. A wider root angle, representing a shallow root system, correlated with grain iron (Fe) concentration at most sites. The total length of all roots (TLAR) and total length of primary roots (TLPR) correlated with grain S concentration at most sites. Narrow root angle in juvenile plants could be a useful proxy trait for screening germplasm for improved grain yield. Lateral root and shallow root traits could potentially be used to improve grain mineral concentrations. The use of juvenile root traits should be explored further in wheat breeding for diverse environments.

Open access

Glyphosate, the active compound of Roundup, is one of the most used pesticides in the world. Its residues are often detected in animal feed, but the impact on the animal gut microbiota and on pathogens of the intestine has not intensively been investigated. In this study, we analyzed the minimum inhibitory concentration (MIC) of glyphosate isopropylamine salt and a common glyphosate-containing herbicide formulation in 225 Salmonella enterica isolates by broth microdilution. A bacteriostatic effect of glyphosate on Salmonella growth was detected at the concentration range of 10 to 80 mg/mL for both the active ingredient and the ready-to-use formulation. Time/year of isolation, host species, and serovars revealed a statistically significant influence on MIC values. Recently collected Salmonella isolates had significantly higher MIC values for glyphosate and the glyphosate-containing product compared with isolates collected between 1981 and 1990. Isolates from pigs showed significantly higher MIC values compared with isolates from poultry, and isolates of the Salmonella serovar Typhimurium had significantly higher MIC values than Salmonella Enteritidis and Infantis isolates.

Open access

Introduction

Most of the studies investigating the effect of early rearing environment in dogs used laboratory dogs and reported that early experiences markedly affect the puppies’ behavior. However, the subjects of these experiments cannot be considered as representatives of family dogs.

Methods

In this study, we investigated whether different raising conditions shape social behavior toward humans in 8-week-old family dog puppies of two breeds, Labrador and Czechoslovakian wolf dog. The puppies were tested in a series of tests that represented typical situations of family dogs.

Results

We found that Czechoslovakian wolf dog puppies were more active than Labrador puppies in general, as they were more likely to explore the environment and the objects and spent more time doing so. Tendency to gaze at humans also varied between breeds, but in a context-specific way. Additionally, puppies housed separately from their mother interacted more with toys, puppies housed in a kennel tended to stay closer to the experimenter than puppies raised in the house, and puppies housed in a kennel tended to stay in the proximity of the experimenter more than puppies raised in the house.

Conclusions

Our results provide evidence for early keeping conditions influencing social behavior and also highlight breed differences in puppies’ behavior. Whether these differences are due to different developmental patterns and/or behavioral predispositions remains to be explored.

Open access
Authors: Elizabeth M. Marlowe, Peter Gohl, Michael Steidle, Rodney Arcenas and Carolin Bier

Trichomoniasis, a common curable sexually transmitted infection caused by the protozoan Trichomonas vaginalis (TV), is usually asymptomatic. However, symptomatic women may experience vaginal discharge and/or vulvar irritation. This study evaluated cobas® TV/ Mycoplasma genitalium (MG) (Conformité Européene marking for in vitro diagnostic medical devices [CE-IVD]) against other nucleic acid amplification tests (NAATs) for detecting TV in female urogenital specimens. Matched de-identified specimens from 412 females were collected. cobas® TV/MG results were compared against a composite reference (CR) of 3 different NAATs for TV (Aptima TV, modified S-DiaMGTV™, and a laboratory-developed test). The overall TV prevalence rate was 6.2%, based on cobas® TV/MG results. Relative to the CR, cobas® TV/MG sensitivity/specificity for the specimen types were endocervical swabs (ES) 100%/99.2%, vaginal swabs (VS) 100%/99.7%, urine (U) 100%/99.7%, and cervical specimens in PreservCyt® solution (PC) 100%/99.5%. There was no significant statistical difference between clinician-collected and self-collected VS (p = 0.28). Correlation of cobas® TV/MG vs. Aptima TV demonstrated the following positive, negative, and overall percent agreements, respectively: ES 69.0%, 98.7%, and 96.6%; VS 88.9%, 99.5%, and 98.8%; U 100%, 100%, and 100%; and PC 95.5%, 99.0%, and 98.8%. Detection of TV with cobas® TV/MG for use on the cobas® 6800/8800 systems demonstrated excellent performance in female urogenital specimens (overall sensitivity/specificity of 100%/≥99.2%).

Open access

Abstract

The relationships between frugivorous animals and plants are of vital importance particularly in tropical forests. The way species interact and how they are organized within interaction networks could be determined by their ecological and morphological characteristics. This study evaluates the hypothesis that the topological position of species within an interaction network is determined by their degree of frugivory, body size, and abundance. Thus, we constructed the frugivory network between birds and plants in a rainforest fragment in northwestern Colombia. The position of the species within the network was calculated based on three centrality measures (degree, betweenness, and closeness), and its association with relative abundance, degree of frugivory, and body size of each bird species was evaluated by means of a generalized linear model. We found that the species that were most abundant and had the smallest body size had central positions in the interaction network. This pattern is contrary to what has been observed in pristine forests, where species with large body size are more important for network stability. Our results suggest that forest fragmentation modifies the roles of species within the network structure, in part, due to changes in the makeup of the original frugivore community. The information presented may be useful to evaluate the effects of the loss of species as a result of anthropic actions, with the aim of generating ecosystem restoration strategies.

Open access

Abstract

A growing number of ecological studies suggest that animal distributions are not only influenced by classical ecological features such as habitat availability, but also by the motion capacity of the studied animal. Here we analyse the diversity and density of two wintering raptor communities from Crete and Sicily, two large Mediterranean islands located along migratory flyways. We performed 611 and 1030 km of transects in Crete and Sicily respectively, examining the spatial distribution of raptors in relation to land use, topography, raptor species diversity and abundance. Our results show that community diversity and specific abundance are strictly related in accordance with the ‘More Individuals Hypothesis’. Comparing the two most common raptors, the density of the Eurasian kestrel was the highest in Sicily and that of the common buzzard in Crete. An overall positive effect of Eurasian kestrel density on that of the common buzzard was found in both islands, but higher in Crete. Our findings suggest that the distribution and density of the Eurasian kestrel, because of its higher movement ability, are less influenced by the presence of ecological barriers along potentially migratory flyways. We cannot exclude that higher inter specific competition with common buzzards in Crete might have pushed the smaller species to cross the Mediterranean Sea in order to overwinter in Africa.

Open access

Abstract

Biological invasion is a crucial problem in the world because of its negative consequences for protected areas. The degradation stage of vegetation might affect the success of invasion. One of the most abundant and threatening invasive species is the common milkweed (Asclepias syriaca L.) which has invaded already 23 countries of Europe and in several habitat types its further spreading is promoted by climate change. Pannonian sand grassland is one of the most threatened habitat by common milkweed invasion. Therefore, invasion in sand grassland vegetation is an important issue. However, the effects of the invasive plant in the open sand grassland are rather controversial. In order to clarify the existing contradictory results, the study was carried out in a strictly protected area, near Fülöpháza (Hungary) in a reserve core area in a UNESCO biosphere reserve. Microcoenological study was applied to determinate the fine-scale community characteristics of non-invaded and invaded stands in natural and seminatural vegetation and data were processed by Juhász-Nagy's information theory models. Shannon diversity of species combinations (compositional diversity) which describes the ways of the coexistence of species, and the number of realized species combinations were used for measuring beta diversity. Differences between stands were analyzed by two-way ANOVA. The maximum compositional diversity of species and main life-forms (annuals, perennials and cryptogams) did not differ significantly between the non-invaded and invaded stands. In contrast, significantly larger characteristic areas of compositional diversity were detected in the invaded stands. Based on these results, it could be concluded that diversity of species combinations did not change but those values have shifted to coarser scales in case of invaded stands. The direction of this change suggests a kind of impoverishment in the presence of Asclepias. Thus, it is worth mentioning from the invasion management point of view that protection of the habitats against disturbance is a more cost-effective and successful way than protection against the establishment or extirpation of invasive species, since disturbance facilitates the invasions throughout the impoverishment of the community.

Open access

Abstract

Functional responses measure the trophic interactions between species, taking into account the density and behavior of the interacting species. In predator-prey interactions, the prey preference of the predator and the antipredator behavior of the prey together determine the feeding rate of the predator and the survival rate of the prey. Consequently, the behavior dependent functional responses make it possible to establish dynamic ecological models providing insight, among others, into the coexistence of predator and prey species and the efficiency of agents in biological pest control. In this paper the derivation methods of functional responses are reviewed. Basically, there are three classes of such methods: heuristic, stochastic and deterministic ones. All of them can take account of the behavior of the predator and prey. There are three main stochastic methods for the derivation of functional responses: renewal theory, Markov chain and the Wald equality-based method. All these methods assume that during the foraging process the prey densities do not change, which provides a mathematical basis for heuristic derivation. There are two deterministic methods using differential equations. The first one also assumes that during the foraging process the prey densities do not change, while the second one does not use that assumption. These derivation methods are appropriate to handle the behavior dependent functional responses, which is essential in the derivation of ecological games, when the payoff of prey and predator depends on the strategies of the prey and predator at the same time.

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Nowadays, multidrug-resistant bacteria are considered as an increasing serious threat to public health worldwide. Global and local surveillance data are helpful in the application of the most efficient antimicrobial agent in bacterial infections. In the current study, we aimed to analyze the activity of the previously cleared agent ceftolozane/tazobactam (C/T) in African and European multidrug-resistant Gram-negative bacteria. Susceptibility testing was performed on 147 extended-spectrum β-lactamase (107 Escherichia coli and 40 Klebsiella pneumoniae) and 103 carbapenemase-producing Gram-negative bacteria using Etest according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) clinical breakpoints. Among the extended-spectrum β-lactamase producing isolates, 91 Escherichia coli isolates (85%) and 23 Klebsiella pneumoniae isolates (57.5%) were susceptible towards C/T whereas out of the 103 carbapenemase-producing isolates 102 (99.0%) were C/T-resistant. C/T should be included in susceptibility testing to fairly administer this antimicrobial agent in infections caused by multidrug-resistant bacteria. It may be considered as a therapy option for infections caused by extended-spectrum β-lactamase-producing bacteria once susceptibility to this antimicrobial combination has been confirmed.

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This paper presents the phytosociological description of a drained swamp community, Veratro albi-Fraxinetum angustifoliae, so far found only in the Nyírség at Nyírábrány “Kis-kőrises”, “Mogyorósi-erdő”; Vámospércs “Jónásrész-Kőrises”; and Vámospércs “Jónásrész-Buzita”. The habitat of the community is transitional between that of alder swamps (Fraxino pannonicae-Alnetum glutinosae), and hardwood riparian forests (Fraxino pannonicae-Ulmetum). The community is characterised by high proportions of character species of Alnion glutinosae and Molinion coerulei as well as Quercetea pubescentis-petraeae s. l. whereas character species of the order Fagetalia are almost completely absent. It hosts several rare, often threatened species, such as Angelica palustris, Ophioglossum vulgatum, Trollius europaeus and Veratrum album.