Characterization of mammary pathogenic Escherichia coli reveals the diversity of Escherichia coli isolates associated with bovine clinical mastitis in Brazil.

Mammary pathogenic Escherichia coli (MPEC) is one of the most common pathogens associated with clinical mastitis. We analyzed isolates obtained from milk samples of cows with clinical mastitis, collected from 10 farms in Brazil, to verify molecular and phenotypic characteristics. A total of 192 (4.

Short communication: Investigation of extra-intestinal pathogenic Escherichia coli virulence genes, bacterial motility, and multidrug resistance pattern of strains isolated from dairy cows with different severity scores of clinical mastitis.

Escherichia coli is a major pathogen involved in the etiology of environmentally derived bovine mastitis and is characterized by a variety of virulence factors (VF). Mammary infections with E. coli have shown a wide range of clinical signs, causing changes in milk (score 1, or mild), abnormal appearance of milk and udder inflammation (score 2, or moderate), and abnormalities in milk, udder inflammation, and systemic signs of illness (score 3, or severe).

Novel findings on the impact of chytridiomycosis on the cardiac function of anurans: sensitive vs. tolerant species.

Background: Understanding of the physiological effects of chytridiomycosis is crucial to worldwide amphibian conservation. Therefore, we analyzed the cardiac function of two anuran species ( and ) with different susceptibilities to infection by the causative agent of chytridiomycosis, (hereafter ).

Methods: We analyzed the heart rate ( - bpm), relative ventricular mass (RVM -%), and Ca handling in heart of infected animals compared to uninfected controls of both study species.

Morphology, Ultrastructure, and Molecular Phylogeny of Rozella multimorpha, a New Species in Cryptomycota.

Increasing numbers of sequences of basal fungi from environmental DNA studies are being deposited in public databases. Many of these sequences remain unclassified below the phylum level because sequence information from identified species is sparse. Lack of basic biological knowledge due to a dearth of identified species is extreme in Cryptomycota, a new phylum widespread in the environment and phylogenetically basal within the fungal lineage.

Diversity of class 1 and 2 integrons detected in Escherichia coli isolates from diseased and apparently healthy dogs.

Escherichia coli is one of the major pathogens causing urinary tract infections (UTIs) and pyometra in dogs. The aims of this study were to investigate canine E. coli isolates for the presence of class 1 and 2 integrons by PCR/sequencing and to characterize these isolates and their integron-carrying plasmids.

Seasonal Variation in Population Abundance and Chytrid Infection in Stream-Dwelling Frogs of the Brazilian Atlantic Forest.

Enigmatic amphibian declines were first reported in southern and southeastern Brazil in the late 1980s and included several species of stream-dwelling anurans (families Hylodidae and Cycloramphidae). At that time, we were unaware of the amphibian-killing fungus Batrachochytrium dendrobatidis (Bd); therefore, pollution, habitat loss, fragmentation and unusual climatic events were hypothesized as primary causes of these declines. We now know that multiple lineages of Bd have infected amphibians of the Brazilian Atlantic forest for over a century, yet declines have not been associated specifically with Bd outbreaks.

Cardiac adaptations of bullfrog tadpoles in response to chytrid infection.

The chytrid fungus Batrachochytrium dendrobatidis (Bd) can result in heart failure in Bd-susceptible species. Since Bd infection generally does not cause mortality in North American bullfrogs, the aim of this work was to verify whether this species presents any cardiac adaptation that could improve the tolerance to the fungus. Thus, we analyzed tadpoles' activity level, relative ventricular mass, ventricle morphology, in loco heart frequency, and in vitro cardiac function.

Partitioning the net effect of host diversity on an emerging amphibian pathogen.

The 'dilution effect' (DE) hypothesis predicts that diverse host communities will show reduced disease. The underlying causes of pathogen dilution are complex, because they involve non-additive (driven by host interactions and differential habitat use) and additive (controlled by host species composition) mechanisms. Here, we used measures of complementarity and selection traditionally employed in the field of biodiversity-ecosystem function (BEF) to quantify the net effect of host diversity on disease dynamics of the amphibian-killing fungus Batrachochytrium dendrobatidis (Bd).

Molecular typing and biological characteristics of Pseudomonas aeruginosa isolated from cystic fibrosis patients in Brazil.

The present study had as objective to evaluate the genotypic diversity and biological characteristics, such as hemolysin, protease, elastase of 56 clinical strains of Pseudomonas aeruginosa isolated from 13 cystic fibrosis (CF) patients attending at the School Hospital of Campinas State University (UNICAMP), Brazil. Genotypic diversity has been determined by Ribotyping (RT) and the pattern of the enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) of each strain. The production of elastase was significantly different only among mucoid and nonmucoid isolates.

Type 2 heat-labile enterotoxin (LT-II)-producing Escherichia coli isolated from ostriches with diarrhea.

The culture supernatant of Escherichia coli, isolated from ostriches with diarrhea in Brazil, caused elongation in Vero cell, rounding in Chinese hamster ovary (CHO) cells and a cytoplasmic vacuolation in ostrich embryo fibroblasts (OEF), but it was not cytotoxic for chicken embryo fibroblasts (CEF). These effects were not neutralized by antiserum to cholera toxin. Polymerase chain reaction assays showed that the ostrich E.

Clonal relationships among avian Escherichia coli isolates determined by enterobacterial repetitive intergenic consensus (ERIC)-PCR.

Forty-nine avian Escherichia coli isolates isolated from different outbreak cases of septicemia (24 isolates), swollen head syndrome (14 isolates) and omphalitis (11 isolates), and 30 commensal isolates isolated from poultry with no signs of illness were characterized by enterobacterial repetitive intergenic consensus (ERIC)-PCR technique and their serotypes were determined. The ERIC-PCR profile allowed the typing of the 79 isolates into 68 ERIC-types and grouped the isolates into four main clusters (A-D), with the omphalitis isolates being grouped with the commensals and separated from the septicaemia and swollen head syndrome. These results indicate that ERIC-PCR is a technique that could replace other molecular characterization techniques such as random amplification of polymorphic DNA (RAPD)-PCR and restriction fragment length polymorphism (RFLP), reinforce previous observations that omphalitis isolates are just opportunistic agents, and are consistent with many reports that specific genotypes are responsible for causing specific diseases.