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Virulence and Antifungal Susceptibility of Microsporum canis Strains from Animals and Humans.

The enzymatic and antifungal profiles of dermatophytes play an important role in causing infections in humans and animals. This study aimed to assess the virulence factors produced by Microsporum canis strains, in vitro antifungal profile and the relationship between virulence, antifungal profile and occurrence of lesions in animals and humans. A total of 100 M. canis strains from humans with tinea corporis (n = 10) and from animals presenting (n = 64) or not (n = 26) skin lesions was employed to evaluate phospholipase (Pz), hemolytic (Hz), lipase (Lz), catalase (Ca), and thermotolerance (GI) …

Type III secretion system effectors form robust and flexible intracellular virulence networks.

Infections with many Gram-negative pathogens, including Escherichia coli, Salmonella, Shigella, and Yersinia, rely on type III secretion system (T3SS) effectors. We hypothesized that while hijacking processes within mammalian cells, the effectors operate as a robust network that can tolerate substantial contractions. This was tested in vivo using the mouse pathogen Citrobacter rodentium (encoding 31 effectors). Sequential gene deletions showed that effector essentiality for infection was context dependent and that the network could tolerate 60% contraction while maintaining pathogenicity. Desp

Dietary Isothiocyanates, Sulforaphane and 2-Phenethyl Isothiocyanate, Effectively Impair Vibrio cholerae Virulence.

Vibrio cholerae represents a constant threat to public health, causing widespread infections, especially in developing countries with a sign … inkage, the inhibition of the DNA, and RNA synthesis as well as downregulation of the expression of virulence factors. Most importantly, ITC reduced the toxicity of V. cholerae in the in vitro assays (against Vero and HeLa cells) and in vivo, using Galleria mellonella larvae as an infection model. In conclusion, our data indicate that ITCs might be consider …

Predicting SARS-CoV-2 Weather-Induced Seasonal Virulence from Atmospheric Air Enthalpy.

Following the coronavirus disease 2019 (COVID-19) pandemic, several studies have examined the possibility of correlating the virulence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19, to the climatic conditions of the involved sites; however, inconclusive results have been generally obtained. Although neither air temperature nor humidity can be independently correlated with virus viability, a strong relationship between SARS-CoV-2 virulence and the specific enthalpy of moist air appears to exist, as confirmed by extensive data analysis. Given thi…

Foodborne Klebsiella pneumoniae: Virulence Potential, Antibiotic Resistance, and Risks to Food Safety.

ABSTRACT: Gastrointestinal carriage of Klebsiella pneumoniae is a predisposing factor for liver abscess in several Asian countries. To deter … and carriage of genetic elements (wcaG and capsule types K1, K2, and K54) associated with increased virulence (8%, 11 of 147) was observed by PCR. Multidrug-resistant isolates were from raw vegetables, chicken or pork liver, and a ready-to-eat poultry dish; one multidrug-resistant K. pneumoniae isolate from raw bean sprouts was resistant to a third-generati …

A non-canonical RNAi pathway controls virulence and genome stability in Mucorales.

Epimutations in fungal pathogens are emerging as novel phenomena that could explain the fast-developing resistance to antifungal drugs and o … R3B2 to degrade target transcripts. Here in this work, we uncovered the role of NCRIP in regulating virulence processes and transposon movements through key components of the pathway, RdRP1 and R3B2. Mutants in these genes are unable to launch a proper virulence response to macrophage phagocytosis, resulting in a decreased virulence potential. The transcrip …

Pathogen transmission from vaccinated hosts can cause dose-dependent reduction in virulence.

Many livestock and human vaccines are leaky because they block symptoms but do not prevent infection or onward transmission. This leakiness is concerning because it increases vaccination coverage required to prevent disease spread and can promote evolution of increased pathogen virulence. Despite leakiness, vaccination may reduce pathogen load, affecting disease transmission dynamics. However, the impacts on post-transmission disease development and infectiousness in contact individuals are unknown. Here, we use transmission experiments involving Marek disease virus (MDV) in chickens to show t…

Clinical cases, drug resistance, and virulence genes profiling in Uropathogenic Escherichia coli.

Uropathogenic Escherichia coli (UPEC) as the most important bacterial agent of urinary tract infections (UTIs) encompasses a wide treasure of virulence genes and factors. In due to this default, the aim of this research was to detect and identify some important virulence genes including cnf1, upaH, hlyA, ibeA, and cdtB in isolated UPEC pathotypes. In this research, clinical samples of urine were collected in Shahr-e-Qods, Tehran, Iran. The UPEC pathotypes were confirmed by standard biochemical tests. The DNAs of isolated bacteria were extracted. The genes of cnf1, upaH, hlyA, ibeA, and cdtB we…

Post-Traumatic Endophthalmitis Due to Acinetobacter radioresistens: Virulence Potential of Commensal Bacteria.

Acinetobacter species are widely distributed in soil, water and hospital environment. In addition to A. calcoaceticus-baumannii complex, the clinically most relevant species, there are other genomospecies which are less frequently identified, mostly due to lack of accurate methods for routine identification. We describe the first case of post-traumatic endophthalmitis caused by otherwise non-pathogenic A. radioresistens, in India. Gram-negative coccobacilli were observed on Gram stain and culture of vitreous fluid specimen, and identified biochemically as Acinetobacter spp. The species was ide

Несоответствия вирулентности в индексных хост-компаниях определяют результаты межвидовой передачи.

Независимо от того, приводит ли патоген, попадающий в новый вид, к одной инфекции или к последующей передаче, а потенциально и к вспышке, зависит от развития инфекции в случае индекса. Хотя индексные инфекционные заболевания редко заметны по своему характеру, экспериментальные прививки патогенов на новые виды являются богатым и в значительной степени неиспользуемым источником данных для мета-анализов с целью выявления хост- и патогенных детерминант изменчивости результатов инфекции. Мы проанализировали прогресс 514 экспериментальных перекрестных прививок от вируса бешенства, широко распростран

Совпадение в аннотации оригинала
Whether a pathogen entering a new host species results in a single infection or in onward transmission, and potentially an outbreak, depends … dose. Taken together, these results suggest that as host species become more dissimilar, increased virulence might act as a limiting factor preventing onward transmission. These results can explain observed constraints on rabies virus host shifts, describe a previously unrecognized role of host body temperature, and provide a potential explanation for host …

Quorum sensing controls persistence, resuscitation, and virulence of Legionella subpopulations in biofilms.

The water-borne bacterium Legionella pneumophila is the causative agent of Legionnaires' disease. In the environment, the opportunistic path … formation of individual bacteria. Nongrowing L. pneumophila cells are metabolically active, express virulence genes and show tolerance toward antibiotics. Therefore, these sessile nongrowers are persisters. Taken together, the Lqs system, LvbR and the temperature control the phenotypic heterogeneity of sessile L. pneumophila, and these factors regulate the …

Virulence characterization and comparative genomics of Listeria monocytogenes sequence type 155 strains.

BACKGROUND: Listeria (L.) monocytogenes strains show a high diversity regarding stress tolerance and virulence potential. Genome studies have mainly focused on specific sequence types (STs) predominantly associated with either food or human listeriosis. This study focused on the prevalent ST155, showing equal distribution among clinical and food isolates. We evaluated the virulence potential of 20 ST155 strains and performed comparative genomic analysis of 130 ST155 strains isolated from food, food processing environments and human listeriosis cases in different countries and years. RESULTS: …

Targeting Two-Component Systems Uncovers a Small-Molecule Inhibitor of Salmonella Virulence.

Salmonella serovars are leading causes of gastrointestinal disease and have become increasingly resistant to fluoroquinolone and cephalosporin antibiotics. Overcoming this healthcare crisis requires new approaches in antibiotic discovery and the identification of unique bacterial targets. In this work, we describe a chemical genomics approach to identify inhibitors of Salmonella virulence. From a cell-based, promoter reporter screen of ∼50,000 small molecules, we identified dephostatin as a non-antibiotic compound that inhibits intracellular virulence factors and polymyxin resistance genes. De…

The antifungal and Cryptococcus neoformans virulence attenuating activity of Pelargonium sidoides extracts.

ETHNOPHARMACOLOGICAL RELEVANCE: Limitations of clinical antifungal treatments and drug-resistance are drivers of the search for novel antifu … Cryptococcus neoformans as well as the effects of both tuber and aerial tissue extracts on selected virulence factors. AIM OF THE STUDY: Novel antimicrobial strategies that target multiple cellular pathways or make use of anti-pathogenic compounds that inhibit virulence factors have been proposed. This work aimed to evaluate P. sidoides plant parts for the …

Pathogenicity patterns of mucormycosis: epidemiology, interaction with immune cells and virulence factors.

Fungi of the basal lineage order Mucorales are able to cause infections in animals and humans. Mucormycosis is a well-known, life-threatenin … of the interaction of Mucorales with cells of the innate immune system, (iii) the assessment of the virulence of Mucorales in vertebrate and invertebrate infection models, and (iv) the determination of virulence factors that are key players in the infection process, for example, high-affinity iron permease (FTR1), spore coat protein (CotH), alkaline Rhizopu …

Virulence factor genotyping of Helicobacter pylori isolated from Costa Rican dyspeptic patients.

BACKGROUND AND AIMS: Costa Rica is one of the countries with the highest incidence and mortality rates for gastric cancer. Helicobacter pylori infection rates are high in the whole country. We have previously shown that H. pylori CagA+ is significantly associated with atrophic gastritis (AG) of the antrum in a dyspeptic population. The aim of this work is to determine if other H. pylori virulence factors (vacA, dupA, oipA, iceA and babA2) are associated with atrophic gastritis (AG) or duodenal ulcer (DU). METHODS: The presence of virulence genes in Costa Rican H. pylori isolates was analyzed …

Virulence determinants and biofilm formation of Acinetobacter baumannii isolated from hospitalized patients.

INTRODUCTION: Acinetobacter baumannii are nosocomial bacteria that are responsible for outbreaks and severe infections in hospitalized patients globally. The major target of this study was the characterization of virulence determinants and biofilm formation of A. baumannii isolates from hospitalized patients. METHODS: In total, 100 A. baumannii were collected from three hospitals in Tehran, Iran, 2017-2018. The isolates were assessed using phenotypic and genotypic methods and then screened for virulence factor encoding genes such as plcN and lasB using conventional polymerase chain reaction. …

Membrane associated proteins of two Trichomonas gallinae clones vary with the virulence.

Oropharyngeal avian trichomonosis is mainly caused by Trichomonas gallinae, a protozoan parasite that affects the upper digestive tract of birds. Lesions of the disease are characterized by severe inflammation which may result in fatality by starvation. Two genotypes of T. gallinae were found to be widely distributed in different bird species all over the world. Differences in the host distribution and association with lesions of both genotypes have been reported. However, so far no distinct virulence factors of this parasite have been described and studies might suffer from possible co-infect…

Validation of Predicted Virulence Factors in Listeria monocytogenes Identified Using Comparative Genomics.

Listeria monocytogenes is an intracellular facultative pathogen that causes listeriosis, a foodborne zoonotic infection. There are differences in the pathogenic potential of L. monocytogenes subtypes and strains. Comparison of the genome sequences among L. monocytogenes pathogenic strains EGD-e and F2365 with nonpathogenic L. innocua CLIP1182 and L. monocytogenes strain HCC23 revealed a set of proteins that were present in pathogenic strains and had no orthologs among the nonpathogenic strains. Among the candidate virulence factors are five proteins: putrescine carbamoyltransferase; InlH/InlC2…

Haitian Variant Vibrio cholerae O1 Strains Manifest Higher Virulence in Animal Models.

Vibrio cholerae causes fatal diarrheal disease cholera in humans due to consumption of contaminated water and food. To instigate the disease, the bacterium must evade the host intestinal innate immune system; penetrate the mucus layer of the small intestine, adhere and multiply on the surface of microvilli and produce toxin(s) through the action of virulence associated genes. V. cholerae O1 that has caused a major cholera outbreak in Haiti contained several unique genetic signatures. These novel traits are used to differentiate them from the canonical El Tor strains. Several studies reported t…