10 research outputs found
Fishmeal extract bile salt lactose agar–A differential medium for enteric bacteria
675-678Fishmeal extract
bile salt lactose agar (FEBLA), a new differential medium for enteric bacteria
was developed and evaluated for its ability to grow and differentiate lactose
fermenters (LF) from non-lactose fermenters (NLF) in comparison with MacConkeys
agar. Performance of FEBLA was at par with the latter. On FEBLA medium, the
contrast between LF and NLF colonies was pronounced and Klebsiella pneumoniae produced more mucoid colonies than on
MacConkeys agar (Hi Media). Unlike MacConkeys agar, a 24 h culture of K. pneumoniae cells on FEBLA were longer
and thicker with abundant capsular material around the bacilli. Escherichia coli produced long and thick
cells but only after 48h. No change in cell morphology was evident with regard
to Salmonella typhi, S. paratyphi A, Shigella flexneri, Pseudomonas aeruginosa, Proteus
mirabilis, Proteus vulgaris, Citrobacter koseri and Acinetobacter baumannii. Performance of
the medium was controlled using E. coli
and S. flexneri. FEBLA is simple,
cost effective and may be a suitable alternative in the preliminary
identification of enteric bacteria. </b
Biotypes and virulence factors of Gardnerella vaginalis isolated from cases of bacterial vaginosis
The present study was conducted to correlate the biotypes of
Gardnerella vaginalis strains isolated from cases of bacterial
vaginosis and their virulence factors. Thirty-two strains of G.
vaginalis isolated from cases of bacterial vaginosis were biotyped.
Adherence to vaginal epithelial cells, biofilm production, surface
hydrophobicity, phospholipase C and protease activity were tested on
these isolates. Biotype 1 was the most prevalent (8; 25%), followed by
biotype 2 (7; 21.9%) and biotypes 5 and 8 (5; 15.6%). We did not find
any statistical correlation between G. vaginalis biotypes and its
virulence factors. Virulence factors expressed by G. vaginalis were not
associated with a single biotype
Genotypic and Phenotypic Expression of Antibiotic Resistance Patterns of Uropathogenic Enterobacteriaceae
Elizabeth Gantasala,1 Sevitha Bhat,2 Vishwas Saralaya,2 Madhumitha Jayaram,1 Jeppu Udayalaxmi2 1Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, Karnataka, India; 2Department of Microbiology, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, IndiaCorrespondence: Jeppu Udayalaxmi, Department of Microbiology, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India, Tel +91 824-2423452, Email [email protected]: To determine the antibiotic resistance patterns, detection of carbapenemase genes in uropathogenic bacilli belonging to the Enterobacteriaceae family and to correlate it with clinical data.Materials and Methods: Identification and antibiotic sensitivity testing of the uropathogenic Enterobacteriaceae was done by using VITEK2 Compact (C) system. Multiplex PCR was used to detect blaIMP, blaKPC, blaNDM1, blaOXA − 48, and blaVIM genes.Results: Out of 1602 urine samples, 417 (26%) showed significant growth, and in these 311 (74.6%) belonged to the Enterobacteriaceae family. Escherichia coli showed a relatively low rate of resistance to nitrofurantoin (17/205; 8.3%), with the majority of the isolates showing a MIC value of ≤ 16 μg/mL when compared to Klebsiella spp. (55/86; 64%), with MIC values for the majority of isolates being 128 μg/mL. Klebsiella spp. showed a relatively low rate of resistance to nalidixic acid (48/86; 55.8%) when compared with E. coli isolates (179/205; 87.3%). Out of 145 isolates tested, we found blaNDM in 11 (7.58%), bla OXA − 48 in 8 (5.51%), bla VIM in 4 (2.75%), bla KPC in one (0.6%) and blaIMP in none of the isolates. Of these 3 isolates were carbapenem sensitive, the rest were resistant.Conclusion: Most of the isolates were sensitive to fosfomycin, carbapenems and resistant to cephalosporins and nalidixic acid. We detected carbapenemase genes in 13 (59%) out of 22 carbapenem resistant isolates and 3 (2.4%) out of 123 carbapenem sensitive isolates.Keywords: antibacterial agents, drug resistance, multiplex polymerase chain reaction, urinary tract infectio
Etiology of bacterial vaginosis and polymicrobial biofilm formation
Microorganisms in nature rarely exist in a planktonic form, but in the form of biofilms. Biofilms have been identified as the cause of many chronic and persistent infections and have been implicated in the etiology of bacterial vaginosis (BV). Bacterial vaginosis is the most common form of vaginal infection in women of reproductive age. Similar to other biofilm infections, BV biofilms protect the BV-related bacteria against antibiotics and cause recurrent BV. In this review, an overview of BV-related bacteria, conceptual models and the stages involved in the polymicrobial BV biofilm formation will be discussed.The South African Medical Research Council (MRC)http://www.tandfonline.com/loi/imby202018-03-30hj2017Medical Microbiolog
Normal flora and bacterial vaginosis in pregnancy: an overview
The female genital tract is an intricate, yet balanced ecosystem that hosts a variety of
different residential microflora. The physiological changes that occur during pregnancy may
disrupt this balanced ecosystem and predispose women to a potentially pathogenic
microbiota. Bacteria that are associated with bacterial vaginosis (BV) are opportunistic
pathogens that frequently form part of this microbiota. The overgrowth of and infections
with these bacteria are linked to poor obstetric outcomes and increased transmission of other
reproductive tract infections (RTIs). These infections increase women’s susceptibility of
acquiring HIV, the rates of HIV shedding and the development of Acquired Immune Deficiency Syndrome (AIDS) in HIV infected patients. It is unknown how the plethora of
bacterial species associated with BV contributes to the dynamics of this condition. The use
of high-throughput methods have led to the in-depth investigation of different BV-related
bacterial species and the functional capabilities of these species. However, the pathogenesis
of BV is still poorly defined and the role of individual BV-related bacterial species in specific
pregnancy complications is unclear and controversial. The majority of BV infections are
asymptomatic and successful diagnosis is complicated by the lack of reliable and
standardized diagnostic tests.University of Pretoria, the Medical Research Council
(South Africa) and the National Health Laboratory Service (NHLS).http://www.tandfonline.com/loi/imby202017-05-31hb2016Medical Microbiolog
Clinical features of bacterial vaginosis in a murine model of vaginal infection with Gardnerella vaginalis.
Bacterial vaginosis (BV) is a dysbiosis of the vaginal flora characterized by a shift from a Lactobacillus-dominant environment to a polymicrobial mixture including Actinobacteria and gram-negative bacilli. BV is a common vaginal condition in women and is associated with increased risk of sexually transmitted infection and adverse pregnancy outcomes such as preterm birth. Gardnerella vaginalis is one of the most frequently isolated bacterial species in BV. However, there has been much debate in the literature concerning the contribution of G. vaginalis to the etiology of BV, since it is also present in a significant proportion of healthy women. Here we present a new murine vaginal infection model with a clinical isolate of G. vaginalis. Our data demonstrate that this model displays key features used clinically to diagnose BV, including the presence of sialidase activity and exfoliated epithelial cells with adherent bacteria (reminiscent of clue cells). G. vaginalis was capable of ascending uterine infection, which correlated with the degree of vaginal infection and level of vaginal sialidase activity. The host response to G. vaginalis infection was characterized by robust vaginal epithelial cell exfoliation in the absence of histological inflammation. Our analyses of clinical specimens from women with BV revealed a measureable epithelial exfoliation response compared to women with normal flora, a phenotype that, to our knowledge, is measured here for the first time. The results of this study demonstrate that G. vaginalis is sufficient to cause BV phenotypes and suggest that this organism may contribute to BV etiology and associated complications. This is the first time vaginal infection by a BV associated bacterium in an animal has been shown to parallel the human disease with regard to clinical diagnostic features. Future studies with this model should facilitate investigation of important questions regarding BV etiology, pathogenesis and associated complications