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Abstract

Due to the increasing application of antibiotics not only in healthcare settings but also in conventional agriculture and farming, multidrug-resistant (MDR) bacterial pathogens are rising worldwide. Given the increasing prevalence of infections caused by MDR bacteria such as Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter species (ESKAPE pathogen complex), it is pivotal to explore novel alternative or adjunct treatment options such as phytochemicals with antibiotic properties. Vanillin and vanillin acid represent biologically active ingredients in vanilla that has been known for long for its health-beneficial including antimicrobial effects besides its role as flavoring agent. Therefore, we performed a literature search from the past 10 years summarizing the knowledge regarding the effects of vanilla constituents against bacterial including MDR pathogens. Our survey revealed that vanillin and vanillic acid exerted potent effects directed against distinct Gram-positive and Gram-negative bacteria by inhibiting growth, viability, biofilm formation, quorum sensing and virulence. Remarkably, when combining vanillin or vanillic acid with defined synthetic antibiotics pronounced synergistic effects directed against distinct pathogenic including ESCAPE strains could be observed. In conclusion, vanilla ingredients constitute promising alternative or adjunct options in the combat of infections caused by MDR bacterial pathogens.

Open access

Abstract

In line with the current development of individualized cancer treatments, targeted and specialized therapeutic regimens such as immunotherapy gain importance and factors improving its efficacy come into the focus of actual research. Given the orchestrated interaction of the intestinal microbiota with host immunity the modulation of the human gut microbiota represents a therapy-enhancing factor. We therefore performed an actual literature survey on the role of the gut microbiota composition and the effects of its modification during immunotherapy of cancer patients. The included 23 studies published in the past 10 years revealed that both, distinct bacterial species and genera including Faecalibacterium prausnitzii and Bifidobacterium, respectively, enhanced distinct immunotherapy responses following PD-1/PD-L1 and CTLA-4 blockage, for instance, resulting in a better clinical outcome of cancer patients. Conversely, a high intestinal abundance of Bacteroidetes and Fusobacterium species correlated with a less efficient immunotherapy resulting in shorter progress-free survival outcomes. In conclusion, modifications of the gut microbiota by fecal microbiota transplantation or application of probiotic compounds represent potential adjunct options for immunotherapy in cancer patients which needs to be further addressed in future trials to provide individually tailored and safe adjuvant therapeutic measures in the combat of cancer.

Open access

Abstract

Intestinal amoebiasis in a 35-year-old German patient with a 3 weeks travel history in Indonesia was initially misidentified as non-steroidal anti-inflammatory-drug associated colitis in colonoscopy and histopathological analysis. Furthermore, initial stool examination by microscopy and Entamoeba faecal antigen ELISA did not reveal any protozoan infection. When cessation of non-steroidal anti-inflammatory drug (NSAID) use and mesalazine treatment did not lead to clinical improvement, the patient presented to a specialist for tropical diseases. An intensive reinvestigation including a workup of formalin-fixed, paraffin-embedded colonic biopsies by molecular analysis with real-time PCR and fluorescence in situ hybridization (FISH) proofed the diagnosis of Entamoeba histolytica colitis. Molecular methods including real-time PCR and FISH for the diagnosis of amoebiasis from histopathological samples are rarely used for the diagnosis of E. histolytica infections. Bloody diarrhoea vanished after the onset of metronidazole treatment. In conclusion, the here-presented case demonstrates how modern molecular diagnostics may help to diagnose E. histolytica-associated colitis, even from difficult specimens like paraffin-embedded, formalin-fixed tissue.

Open access

Abstract

Varroa mite, Varroa destructor is the most important ectoparasite of the honey bee, Apis mellifera worldwide, contributing to colony collapse. The development of alternative non-toxic methods against this pest is needed, as most of the wide-used acaricides in apiculture are banned in the European Union, which increase the risk of developing resistant mite populations against the remaining few products. In order to reveal biological basis of a new, semiochemical-based method, the aim of this study was to search for olfactory stimuli, used by female Varroa mites in orienting to drone brood for egglaying. Volatiles of uncapped drone brood were collected in situ, inside bee-hives, using either charcoal, or HayeSep® Q filters. Collections were analyzed by gas chromatograph linked to an electrotarsogram detector (GC-ETD), using the foreleg of female mite. Results showed that most components were present in collections trapped by any of these filters. However, some components appreared only in charcoal-, while others only in HayeSep® collections, respectively. Out of the large number of components, a few elicited electrophysiological responses. Structure elucidation of these active components are underways. Futher behavioral studies should reveal, which components play role in attraction of Varroa mites.

Open access

Abstract

New data are provided on the distribution of scale insect species based on the soil sample collection of Museo Nacional de Ciencias Naturales, Madrid, Spain. Six species proved to be new to the scale insect fauna of Spain: 1 species of Ortheziidae (Ortheziola vejdovskyi Sulc), 3 species of Pseudococcidae (Fonscolombia graminis Lichtenstein, Peliococcus mathisi (Balachowsky), Rhodania porifera Goux) and 2 species of Rhizoecidae (Rhizoecus arabicus Hambleton, Ripersiella lelloi (Mazzeo)).

Open access
Acta Phytopathologica et Entomologica Hungarica
Authors:
Dominika Bodnár
,
Orsolya Viczián
,
András Juhász
,
József Fodor
,
Péter G. Ott
, and
Emese Mergenthaler

Abstract

Some jumping plant-lice species are economically important due to their capacity as vectors of phytopathogenic bacteria, for example phytoplasmas. Previous studies have identified 80 jumping plant-louse species from Hungary; however, little is known about their occurrence during winter. To extend our knowledge of overwintering sites of jumping plant-lice in Hungary, we sampled them from conifers in various regions of the country. One of our main objectives was to find Cacopsylla pruni (Scopoli, 1763), the vector of ‘Candidatus Phytoplasma prunorum' during winter.

The period of this study extended from 2014 to 2020 in the winter months. Insects were collected at 18 sampling sites from Borsod-Abaúj-Zemplén county to Somogy county, located at Alsótekeres, Balatonvilágos, Boldogkőváralja, Budakeszi, Fenyőfő, Gyöngyöspata, Kecskemét, Martonvásár, Mátra Mountain, Nagykovácsi, Nagyszakácsi, Páty, Piliscsaba, Somogytúr, Soroksár, Sóskút and Verpelét.

A total of 1,600 jumping plant-louse specimens belonging to 20 species and three families (Psyllidae, Aphalaridae and Triozidae) were collected and identified during the study. In the case of plum psyllid (C. pruni) four shelter sites were identified as new records for Hungary.

The most common species were Trioza remota, Cacopsylla melanoneura, Trioza urticae, Bactericera albiventris, C. pruni and Cacopsylla crataegi.

Open access

Abstract

Gut microbiota depletion is a pivotal prerequisite to warrant Campylobacter jejuni infection and induced inflammation in IL-10-/- mice used as acute campylobacteriosis model. We here assessed the impact of an 8-week antibiotic regimen of ampicillin, ciprofloxacin, imipenem, metronidazole, and vancomycin (ABx) as compared to ampicillin plus sulbactam (A/S) on gut microbiota depletion and immunopathological responses upon oral C. jejuni infection. Our obtained results revealed that both antibiotic regimens were comparably effective in depleting the murine gut microbiota facilitating similar pathogenic colonization alongside the gastrointestinal tract following oral infection. Irrespective of the preceding microbiota depletion regimen, mice were similarly compromised by acute C. jejuni induced enterocolitis as indicated by comparable clinical scores and macroscopic as well as microscopic sequelae such as colonic histopathology and apoptosis on day 6 post-infection. Furthermore, innate and adaptive immune cell responses in the large intestines were similar in both infected cohorts, which also held true for intestinal, extra-intestinal and even systemic secretion of pro-inflammatory cytokines such as TNF-α, IFN-γ, and IL-6. In conclusion, gut microbiota depletion in IL-10-/- mice by ampicillin plus sulbactam is sufficient to investigate both, C. jejuni infection and the immunopathological features of acute campylobacteriosis.

Open access
European Journal of Microbiology and Immunology
Authors:
Fatima Zahra Adil
,
Elmostafa Benaissa
,
Yassine Benlahlou
,
Hicham Bakkali
,
Nawfal Doghmi
,
Hicham Balkhi
,
Adil Maleb
, and
Mostafa Elouennass

Abstract

Introduction

Bacteremia is responsible for high rates of morbidity and mortality. The increasing prevalence of multidrug-resistant (MDR) bacteria in intensive care units (ICU) is a growing concern. Hence, prior knowledge of bacterial epidemiology and resistance phenotypes is required to optimize these infections' management. The objective of this study was to determine the epidemiological profile of bacteremia in ICU settings, as well as the place occupied by MDR bacteria in these infections.

Methods

It is a prospective study carried out over 10 months on episodes of bacteremia in the ICU of Mohammed V Military Teaching Hospital (Rabat, Morocco). Microorganism growth was detected using fluorescent technology, species identification was based on morphological and biochemical characteristics. Antimicrobial susceptibility testing was performed following the recommendations of the Antibiogram Committee of the French Society of Microbiology (CA-SFM) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST).

Results

Among 504 hospitalized patients, sixty-one (12.1%) presented at least one episode of bacteremia. Forty patients (65.6% of bacteremic patients) presented at least one episode of bacteremia due to MDR bacteria. Male gender, cardiovascular diseases, diabetes and previous hospitalization were significant risk factors for the acquisition of MDR bacteremia. Isolated bacteria were mainly Gram-negative bacilli (GNB) (n = 62; 68.9%) dominated by Acinetobacter baumannii (n = 19; 21.1%) and Klebsiella pneumoniae (n = 16; 17.8%). MDR bacteria were represented by multi-resistant Acinetobacter baumannii (n = 19; 44.2%), extended-spectrum beta-lactamases-producing Enterobacterales (n = 9; 20.9%) and carbapenem-resistant Enterobacterales (n = 7; 16.3%). Carbapenems (n = 40; 65.6%), Aminoglycosides (n = 32; 52.5%) and Polypeptides (n = 24; 39.3%) were the most used antimicrobials. Mortality rates were 66.6% (n = 40) and 85% (n = 43) in patients with non MDR bacteremia and MDR bacteremia respectively.

Conclusion

Limiting the spread of MDR bacteria and improving the management of bacteremic patients require continuous monitoring of bacteremia as well as adapting the therapeutic and preventive strategy.

Open access
Acta Alimentaria
Authors:
M. Reyzov
,
M. Eftimov
,
S. Gancheva
,
M. Todorova
,
M. Zhelyazkova-Savova
,
M. Tzaneva
, and
S. Valcheva-Kuzmanova

Abstract

Metabolic syndrome (MS) is a serious health condition. The purpose of this study was to investigate the effects of polyphenol-rich Aronia melanocarpa fruit juice (AMFJ) on glucose tolerance, triglyceride levels, and adipose tissue in rats with MS induced by high-fat high-fructose (HFHF) diet. Fifty rats were allocated in 5 groups: control, MS, MS+AMFJ2.5, MS+AMFJ5, and MS+AMFJ10. In the course of 10 weeks, the control group was on a regular rat diet while the other groups received HFHF diet. During the experiment, control and MS groups were treated daily orally with distilled water (10.0 mL kg−1) and the other three groups – with AMFJ at doses of 2.5, 5.0, and 10.0 mL kg−1, respectively. In MS rats, glucose intolerance, hypertriglyceridemia, visceral obesity, and increased adipocyte size were observed. In AMFJ-treated groups, the serum glucose and triglycerides, as well as visceral fat and adipocyte size decreased significantly and did not differ from those of the control group. AMFJ at doses 2.5 and 5.0 mL kg−1 showed an anti-apoptotic activity in adipocytes, while at the dose of 10 mL kg−1 a pro-apoptotic effect was detected. In conclusion, AMFJ could antagonise most of the negative consequences of HFHF diet on carbohydrate and lipid metabolism in a rat MS model.

Open access

Abstract

Non-alcoholic fatty liver disease is one of the most common chronic liver diseases with unclarified pathomechanism and without evidence-proven therapy. Dietary polyphenols, targeting oxidative stress, are at the center of investigations. Our aim was to examine the effects of a polyphenol rich extract on metal element homeostasis and transmethylation ability in non-alcoholic fatty liver model. A ten-day rat model was used (control group, hyperlipidemic group with fat-rich diet, hyperlipidemic group with fat-rich diet and polyphenol supplementation, N = 8 in each group). The hyperlipidemic diet increased the concentration of the majority of the elements with significantly higher contents of B, Co, Cu, Fe, Mg, Mn, Na, Ni, P, Se, Si, and Zn in the liver. Further elevation of Al, Pb, and Sn concentrations could be observed in polyphenol supplemented animals. The polyphenol supplement unexpectedly decreased the transmethylation ability of the liver (132.00 vs. 114.15 vs. 92.25 HCHO μg g−1) further. The results emphasize the possible role of altered metal and non-metal element concentrations and decreased transmethylation ability in the pathomechanism of fatty liver disease. Dietary supplementation with natural compounds may have undesirable effect as well, there is the necessity to improve the efficacy of polyphenol formulations because of their low oral bioavailability.

Open access