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European Journal of Microbiology and Immunology
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
European Journal of Microbiology and Immunology
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
Biologia Futura
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
European Journal of Microbiology and Immunology
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
Biologia Futura
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
Biologia Futura
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