pestis

Yersinia pestis , the causative agent of plague, is capable of evading the human immune system response by recruiting the plasma circulating vitronectin proteins, which act as a shield and avoid its lysis. Vitronectin recruitment is mediated by its interaction with the bacterial transmembrane protein Ail, protruding from the Y. pestis outer membrane. By using all-atom long-scale molecular dynamic simulations of Ail embedded in a realistic model of the bacterial membrane, we have shown that vitronectin forms a stable complex, mediated by interactions between the disordered moieties of the two proteins...

This study evaluated a depot-formulated cytokine-based adjuvant to improve the efficacy of the recombinant F1V (rF1V) plague vaccine and examined the protective response following aerosol challenge in a murine model. The results of this study showed that co-formulation of the Alhydrogel-adsorbed rF1V plague fusion vaccine with the depot-formulated cytokines recombinant human interleukin 2 (rhuIL-2) and/or recombinant murine granulocyte macrophage colony-stimulating factor (rmGM-CSF) significantly enhances immunogenicity and significant protection at lower antigen doses against a lethal aerosol challenge...

Yersinia pestis is a gram-negative bacterium and the causative agent for the plague. Yersinia spp . use effector proteins of the type III secretion system (T3SS) to skew the host immune response toward a bacterial advantage during infection. Previous work established that mice which lack the type I IFN receptor (IFNAR), exhibit resistance to pulmonary infection by Y. pestis . In this work, we addressed the efficacy of a single dose administration of neutralizing antibody to IFNAR (MAR1) as a preventive treatment for plague...

Yersinia pestis, the causative agent of plague, is a gram-negative bacterium that can be fatal if not treated properly. Three types of plague are currently known: bubonic, septicemic, and pneumonic plague, among which the fatality rate of septicemic and pneumonic plague is very high. Bubonic plague can be treated, but only if antibiotics are used at the initial stage of the infection. But unfortunately, Y. pestis has also shown resistance to certain antibiotics such as kanamycin, minocycline, tetracycline, streptomycin, sulfonamides, spectinomycin, and chloramphenicol...

A Microsoft Excel workbook, User-Friendly Feed Formulation with Data from Australia (UffdAu.xlsm), has been developed for teaching feed formulation techniques to tertiary level, university students. It runs under both Microsoft Windows and Apple iOS operating systems. The example ingredient composition matrix is based on the Australian Feed Ingredient Database to illustrate the biological and econometric principles of least-cost feed formulation. The nutrient data are based roughly on recent primary breeder company recommendations...

We recently identified two virulence-associated small open reading frames (sORF) of Yersinia pestis, named yp1 and yp2, and null mutants of each individual genes were highly attenuated in virulence. Plague vaccine strain EV76 is known for strong reactogenicity, making it not suitable for use in humans. To improve the immune safety of EV76, three mutant strains of EV76, Δyp1, Δyp2, and Δyp1&yp2 were constructed and their virulence attenuation, immunogenicity, and protective efficacy in mice were evaluated...

Bloodstream infections (BSI) are defined by the presence of viable bacteria or fungi, accompanied by systemic signs of infection. Choosing empirical therapy based solely on patient risk factors and prior antibiotic susceptibility test (AST) may lead to either ineffective treatment or unnecessarily broad-spectrum antibiotic exposure. In general, Clinical & Laboratory Standards Institute guideline-approved ASTs have a turnaround time of 48-72 h from sample to answer, a period that may result in a critical delay in the appropriate selection of therapy...

Yersinia pestis, the causative agent of plague, is a highly virulent bacterium that poses a significant threat to human health. Preserving this bacterium in a viable state is crucial for research and diagnostic purposes. This paper presents and evaluates a simple lyophilization protocol for the long-term storage of Y. pestis strains from Fiocruz-CYP, aiming to explore its impact on viability and long-term stability, while replacing the currently used methodologies. The lyophilization tests were conducted using the non-virulent Y...

Microglia are the resident macrophages in the central nervous system, accounting for 10-15% of the cell mass in the brain. Next to their physiological role in development, monitoring neuronal function and the maintenance of homeostasis, microglia are crucial in the brain's immune defense. Brain injury and chronic neurological disorders are associated with neuroinflammation, in which microglia activation is a central element. Microglia acquire a wide spectrum of activation states in the diseased or injured brain, some of which are neurotoxic...

Understanding rodent-ectoparasite interactions and the factors driving them is important in understanding the epidemiology of diseases involving an arthropod vector. Fleas are the primary vector for Yersinia pestis , the bacteria that causes plague and monitoring of flea population is essential for planning the potential mitigation measures to prevent the disease outbreak. In this study, we investigated flea abundance, community structure and the potential factors driving flea infestation in areas with frequent (persistent) and non-frequent plague (non-persistent) outbreaks...

Vaccine strains Yersinia pestis EV NIIEG at a dose of 103 CFU and Francisella tularensis 15 NIIEG at a dose of 102 CFU induced changes in the concentration of cyclic nucleotides in the thymus and spleen of white mice. Antigen-induced changes in the cAMP/cGMP ratio in immunocompetent organs had a phase or oscillatory character, which seems to be related to the regulation of postvaccination immunoreactivity in the body. Synthetic organoselenium compound 974zh stimulated an increase in the amplitude of cAMP/cGMP oscillations, indicating its stimulating effect on the immunogenic properties of vaccine strains at doses an order of magnitude below the standard doses...

Antimicrobial peptide resistance has been proposed to play a major role in the flea-borne transmission of Yersinia pestis . However, the antimicrobial peptide response in fleas and their interaction with Y. pestis is largely unknown. Attacins are one of the most abundantly expressed antimicrobial peptides within the first hours after Y. pestis infection of Xenopsylla cheopis , a major vector of plague. In this study, we report the cloning, expression, and purification of two X. cheopis attacin peptides and describe their interactions with and antimicrobial activities against Y...

UNLABELLED: The Serratia marcescens is a Gram-negative bacterium from the Enterobacteriaceae family. Recently, S. marcescens have evolved to become a versatile and opportunistic pathogen. Furthermore, this bacterium is also a multi-drug resistant pathogen exhibiting Extended-Spectrum Beta-Lactamases (ESBL) activity. This bacterium is highly associated with infections in healthcare settings and even leads to death. Hence, an advanced approach based on non-protein coding RNA (npcRNA) of S...

Climate change is causing many vectors of infectious diseases to expand their geographic distribution as well as the pathogens they transmit are also conditioned by temperature for their multiplication. Within this context, it is worth highlighting the significant role that fleas can play as vectors of important pathogenic bacteria. For this purpose, our efforts focused on detecting and identifying a total of 9 bacterial genera (Rickettsia sp.; Bartonella sp.; Yersinia sp.; Wolbachia sp., Mycobacterium sp., Leishmania sp...

Plague, as an ancient zoonotic disease caused by Yersinia pestis, has brought great disasters. The natural plague focus of Marmota himalayana in the Qinghai-Tibet Plateau is the largest, which has been constantly active and the leading source of human plague in China for decades. Understanding the population genetics of M. himalayana and relating that information to the biogeographic distribution of Yersinia pestis and plague outbreaks are greatly beneficial for the knowledge of plague spillover and arecrucial for pandemic prevention...

The discovery of the 32-bp deletion allele of the chemokine receptor gene CCR5 showed that homozygous carriers display near-complete resistance to HIV infection, irrespective of exposure. Algorithms of molecular evolutionary theory suggested that the CCR5- ∆ 32 mutation occurred but once in the last millennium and rose by strong selective pressure relatively recently to a ~10% allele frequency in Europeans. Several lines of evidence support the hypothesis that CCR5- ∆ 32 was selected due to its protective influence to resist Yersinia pestis, the agent of the Black Death/bubonic plague of the 14th century...

Plague is a flea-borne fatal disease caused by the bacterium Yersinia pestis, which persists in rural Madagascar. Although fleas parasitizing rats are considered the primary vectors of Y. pestis, the human flea, Pulex irritans, is abundant in human habitations in Madagascar, and has been found naturally infected by the plague bacterium during outbreaks. While P. irritans may therefore play a role in plague transmission if present in plague endemic areas, the factors associated with infestation and human exposure within such regions are little explored...

Objectives: This study aimed to create a three-dimensional histological reconstruction through the AI-assisted classification of tissues and the alignment of serial sections. The secondary aim was to evaluate if the novel technique for histological reconstruction accurately replicated the trabecular microarchitecture of bone. This was performed by conducting micromorphometric measurements on the reconstruction and comparing the results obtained with those of microCT reconstructions. Methods: A bone biopsy sample was harvested upon re-entry following sinus floor augmentation...

The genus Yersinia includes human, animal, insect, and plant pathogens as well as many symbionts and harmless bacteria. Within this genus are Yersinia enterocolitica and the Yersinia pseudotuberculosis complex, with four human pathogenic species that are highly related at the genomic level including the causative agent of plague, Yersinia pestis . Extensive laboratory, field work, and clinical research have been conducted to understand the underlying pathogenesis and zoonotic transmission of these pathogens...

INTRODUCTION: Plague is a zoonotic disease that occurs naturally in specific geographic areas. Climate change can influence the populations of the plague host or vector, leading to variations in the occurrence and epidemiology of plague in animals. METHODS: In this study, we collected meteorological and plague epidemiological data from the Marmota himalayana plague focus in the Altun Mountains of the Qinghai-Xizang Plateau. The data spanned from 2000 to 2022. We describe the climatic factors and plague epidemic conditions and we describe their analysis by Pearson's correlation...