Unwrapping the phase portrait features of adventitious crackle for auscultation and classification: a machine learning approach

Journal of Biological Physics - The paper delves into the plausibility of applying fractal, spectral, and nonlinear time series analyses for lung auscultation. The thirty-five sound signals of...     

Effect of metformin and spironolactone therapy on OGTT in patients with polycystic ovarian syndrome - a retrospective analysis

Background: Metformin (an insulin sensitizer) and spironolactone (an antiandrogen) are both used for treatment of polycystic ovary syndrome. We analyzed the effect of 6 months of therapy with these drugs on body weight and glucose tolerance. Results: This was a retrospective analysis of polycystic ovarian syndrome (PCOS) cases on treatment. There were 88 patients with PCOS-42 were on metformin 1 g daily and 46 were taking spironolactone 50-75 mg daily. 21 of 42 had abnormal glucose tolerance (AGT) in the metformin group and 13 of 46 had AGT in the spironolactone group. Patients on metformin reported a greater reduction in body weight, whereas there was no change in body weight with spironolactone therapy (67.6-63.7 versus 59.6-59.2 kg). There was a significant reduction in the 1 and 2 h glucose and insulin levels with metformin therapy in those with AGT. However, fasting glucose increased in those with normal glucose tolerance. There was no change in either body weight or insulin levels with spironolactone. But, there was a significant reduction in both the 0 and 2 h glucose with spironolactone also in those with AGT. Conclusion: Spironolactone and metformin had similar effect in reducing the glucose levels in PCOS patients with AGT. PCOS patients with normal glucose tolerance had higher fasting plasma glucose at the end of 6 months of metformin therapy inspite of weight reduction.     

A study on the effects of some laboratory-derived genetic mutations on biofilm formation by Listeria monocytogenes

Biofilms formed by the human pathogen Listeria monocytogenes in food-processing environments can be a potential source of contamination. In this study, we investigated the ability of L. monocytogenes wild type and its laboratory-derived isogenic mutants in cwhA, prfA, agrA, flaA, degU, ami and sigB to adhere to and form biofilms on abiotic surfaces. The results suggest that inactivation of the two component regulatory system degU completely abolished biofilm formation, while inactivation of the flagellar gene flaA, two component response regulator agrA and the autolysin-adhesin gene ami lead to severe impairment of initial attachment and the subsequent development of a mature biofilm by L. monocytogenes. Mutants in the global regulator of virulence prfA and the alternative sigma factor sigB were unaffected and formed biofilms similar to wild type L. monocytogenes.     

Distribution of Putative Virulence Genes and Antimicrobial Drug Resistance in <Emphasis Type="Italic">Vibrio harveyi</Emphasis>

The marine-estuarine bacterium Vibrio harveyi is an important pathogen of invertebrates, most significantly, the larvae of commercially important shrimp Penaeus monodon. In this study, we analyzed V. harveyi isolated from shrimp hatchery environments for understanding the distribution of putative virulence genes and antimicrobial drug resistance. The putative genes targeted for PCR detection included four reversible toxin (Rtx)/hemolysin genes, a gene encoding homologue of Vibrio cholerae zonula occludens toxin (Zot) and a hemolysin-coregulated protein gene (hcp) by polymerase chain reaction (PCR). Of the four putative reversible toxin genes, vhh-1 was detected in 31% of the isolates, vhh-2 in 46%, vhh-3 in 23% and vhh-4 was detected in 27% of the isolates. A zot-like sequence of bacteriophage f237 was present in 15%, while hcp sequence was detected in 48% of the isolates. The antimicrobial susceptibility test revealed resistance to several groups of antibiotics including β-lactams, cephalosporins, macrolides, quinolones, nitrofurantoin and tetracycline.     

Study of the occurrence of Vibrio vulnificus in oysters in India by polymerase chain reaction (PCR) and heterogeneity among V. vulnificus by randomly amplified polymorphic DNA PCR and gyrB sequence analysis

The pathogenic bacterium Vibrio vulnificus is widely distributed in estuarine waters throughout the world. In this study, the presence of V. vulnificus in oysters was studied both by conventional culture and DNA-based molecular technique. Following enrichment in alkaline peptone water (APW), the bacteria were lysed and a nested polymerase chain reaction (PCR) for vvhA gene was performed. The effect of duration of enrichment on the sensitivity of detection by PCR was evaluated. The organism was isolated from 43% of samples after 18 h enrichment in APW by conventional culture method. Nested PCR amplifying a fragment of vvhA gene detected the organism in 11%, 60% and 81% of samples following 0, 6 and 18 h of enrichment. All the biochemically identified V. vulnificus strains possessed vvhA gene and belonged to biotype 1. The genetic relatedness among the strains was studied by randomly amplified polymorphic DNA (RAPD) PCR and gyrB sequence analysis. The results suggest the presence of two distinct clonal groups of V. vulnificus in oysters in India. The study demonstrates, for the first time that gyrB sequence analysis could be used to study the genetic diversity of V. vulnificus.     

Reproductive endocrine functions in men with primary hypothyroidism: effect of thyroxine replacement

Reproductive endocrine functions were studied in men with primary hypothyroidism during the hypothyroid phase and after achieving euthyroid status with thyroxine substitution therapy. Hypergonadotropism [luteinising hormone (LH), 18.7 +/- 7.3 IU/l; follicle-stimulating hormone (FSH), 6.3 +/- 2.0 IU/l], low serum testosterone (6.1 +/- 2.8 nmol/l), low serum sex-hormone-binding globulin (SHBG; 13.2 +/- 2.0 nmol/l) and subnormal testosterone response to human chorionic gonadotropin hCG; (30% increase in serum testosterone following hCG) observed during the hypothyroid phase were restored to normal (LH, 7.2 +/- 2.0 IU/l; FSH, 2.7 +/- 0.9 IU/l; testosterone, 12.9 +/- 2.7 nmol/l; SHBG, 26.5 +/- 8.4 nmol/l, and 2-fold increase in serum testosterone following hCG) with thyroxine substitution therapy. Some improvement in sperm count and motility was also observed.     

Opisthorchis viverrini: detection by polymerase chain reaction (PCR) in human stool samples

A polymerase chain reaction (PCR) assay was evaluated for detection of Opisthorchis viverrini eggs in the stool specimens of light and heavily infected individuals in Khon Kaen province of Thailand. A total of 75 fecal specimens were analyzed by PCR following DNA extraction. All the microscopically positive samples were positive by PCR, while 23 of 30 (76.6%) microscopically negative samples were also PCR positive. The sensitivity of the assay was 5 eggs/g of stool. This method is potentially useful in the diagnosis of human opisthorchiasis in endemic areas for treatment and in epidemiological investigations.