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S Das

Publications and source records attributed to S Das.

At least 127 records · Page 7Linked to original sources
PubMed2002

A retrospective study of the clinical effectiveness of the treatment of genital co-infection with N. gonorrhoeae and C. trachomatis in Coventry.

Concomitant infection of Neisseria gonorrhoeae and Chlamydia trachomatis is frequent and it is common practice to prescribe ancillary treatment for chlamydial infection when infection with N. gonorrhoeae is suspected or confirmed. In Coventry cases are treated as they are diagnosed. Our objective was to determine the clinical effectiveness of treating gonorrhoea and chlamydial infection separately in cases of co-infection. Case notes of co-infection with N. gonorrhoeae and C. trachomatis diagnosed in Coventry GU clinic from March 1989 to February 2000 were reviewed retrospectively. There were 1250 episodes of gonorrhoea, 4127 of chlamydial infections, and both infections were found in 332 cases. The two infections were treated in 322 cases and in 235 cases were treated separately. Ten cases did not come back for treatment of chlamydial infection, which is less than one case per year and 0.2% of total chlamydial infection in 11 years. On the other hand, 918 (73%) of total number of gonorrhoea patients did not have to take unnecessary treatment for chlamydial infection. In some clinical settings co-infection with N. gonorrhoeae and C. trachomatis could be treated separately with significant success and in the long run this might prevent development of antibiotic resistance of C. trachomatis infection.

Anti-Bacterial Agents↗
PubMed2002

Alopecia universalis in a case of systemic lupus erythematosus.

We report a case of systemic lupus erythematosus (SLE) who presented with alopecia universalis. MR, a 23 years female patient was admitted with alopecia universalis and other features of SLE like peripheral arthritis, fever, nephritis, butterfly rash over the malar regions, positive ANA and anti-ds DNA antibodies. There was a gap of four years between the onset of alopecia universalis and other clinical features of SLE. The alopecia was of non-scarry variety and responded to systemic and topical steroids.

Adult↗
PubMed2002

Cardioprotection with sildenafil, a selective inhibitor of cyclic 3',5'-monophosphate-specific phosphodiesterase 5.

The effects of sildenafil (Viagra), a specific inhibitor of phosphodiesterase 5, on ischemic myocardium was examined using an isolated rat heart model. Rats were pretreated with sildenafil at doses ranging from 0.001 mg to 0.5 mg/kg body weight. After 60 min, isolated hearts were subjected to ischemia for 30 min followed by 2 h of reperfusion. The results demonstrated that at 0.05 mg/kg (and to some extent at 0.01 mg/kg), sildenafil provided significant cardioprotection as evidenced by improved ventricular recovery, a reduced incidence of ventricular fibrillation and decreased myocardial infarction. At higher doses, it caused a significant increase in the incidence of ventricular fibrillation while at very low doses it had no effect on cardiac function. As expected, sildenafil increased cyclic 3',5'-monophosphate (cGMP) content in the heart. The results demonstrate for the first time that within a narrow dose range, sildenafil can protect the heart from ischemia/reperfusion injury, probably through a cGMP-signaling pathway.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed2002

Serotypic and antibiotic susceptibility pattern of Salmonella species isolated from cases of gastroenteritis at Infectious Diseases Hospital (IDH), Delhi from 1997-2000.

A total number of 11,551 stool samples/rectal swabs obtained from acute gastroenteritis cases admitted at Infectious Diseases Hospital (IDH), Delhi during a period of four years from 1997-2000 were processed at National Institute of Communicable Diseases (NICD), Delhi to look for the presence of enteropathogens. One hundred twelve Salmonellae species belonging to different serotypes were isolated. The commonest species was S. typhimurium, accounting for 31% of isolates, followed by S. weltervreden (19%), S. litchfield (15%) and others. 61% of S. typhimurium isolates depicted multidrug resistance to Chloramphenicol, Tetracycline, Furazolidone and Co-trimoxazole. However, none showed resistance to quinolones and third generation cephalosporins. Estimation of minimum inhibitory concentration (MIC) for S. typhimurium against Ampicillin, Chloramphenicol and Cephalothin was carried out by E test. A good correlation between disc diffusion technique and E test was observed.

Adolescent↗
PubMed2002

Worm infestation and anaemia: a public health problem among tribal pre-school children of Madhya Pradesh.

A study to assess the status of intestinal parasitosis and anaemia was carried out among the pre-school children of Gond tribal community in Kundam block of Jabalpur district, Madhya Pradesh. A total of 985 pre-school children were covered. The results revealed that 48% pre-school children had intestinal parasitic infections. Common parasites observed among them were Hymenolepis nana, hookworms and roundworms. Mean epg for these parasites ranged from 371.2 to 1221.8. High prevalence of anaemia (86.7%) was also observed among them. This high prevalence of intestinal parasitic infections and anaemia could be due to indiscriminate defecation, low socio-economic status, ignorance and low standard of personal hygiene. Comprehensive control strategy with specific intervention measures need to be evolved and implemented specially in tribals as serious efforts are being madeby the Govt. for their overall development.

Anemia↗
PubMed2001

Salp25D, an Ixodes scapularis antioxidant, is 1 of 14 immunodominant antigens in engorged tick salivary glands.

Rabbits or guinea pigs infested with Ixodes scapularis acquire resistance to tick bites, a phenomenon, known as tick immunity, that is partially mediated by antibody. To determine the salivary gland antigens that elicit antibodies in the host, an I. scapularis salivary gland cDNA expression library was probed with serum from tick-immune rabbits. Sera from sensitized rabbits strongly recognized 47 of 100,000 library clones in an antibody-screening assay. These 47 clones encoded 14 different I. scapularis genes, including a glutathione peroxidase homologue. Expression of these 14 genes in engorged tick salivary glands was confirmed by reverse-transcription polymerase chain reaction. The I. scapularis glutathione peroxidase homologue, named salp25D, was expressed in both unfed and fed nymphal salivary glands. Recombinant Salp25D was able to catalyze the reduction of hydrogen peroxide in the presence of reduced glutathione and glutathione reductase. These results categorize the prominent salivary gland proteins in I. scapularis and demonstrate the presence of a potent antioxidant in tick saliva.

Amino Acid Sequence↗
PubMed2001

Incomplete penetrance with normal MRI in a woman with germline mutation of the DCX gene.

X-linked isolated lissencephaly sequence (ILS) and subcortical band heterotopia are allelic human disorders associated with mutations of the DCX gene in both familial and sporadic forms. The authors describe a large Sardinian family in which three brothers with ILS have a missense mutation of the DCX gene. Their mother, a nonmosaic carrier, has a normal phenotype and cranial MRI. Skewed X-inactivation in the lymphocytes was also ruled out. This is the first report of an asymptomatic carrier of a DCX mutation likely due to apparent nonpenetrance.

Adolescent↗
PubMed2001

Simultaneous rupture along two conjugate planes of the Wharton Basin earthquake.

Analysis of broadband teleseismic data shows that the 18 June 2000 Wharton Basin earthquake, a moment magnitude 7.8 intraplate event in the region of diffuse deformation separating the Indian and Australian plates, consisted of two subevents that simultaneously ruptured two near-conjugate planes. This mode of rupture accommodates shortening by a mechanism different from that previously known elsewhere in the region. The larger subevent occurred on a fossil fracture zone, with a relatively high stress drop of about 20 megapascals, showing that large stresses can accumulate in regions of distributed deformation.

Journal Article↗
PubMed2001

Morphologic analysis of BMP-9 gene therapy-induced osteogenesis.

The present study was performed to determine the histological, ultrastructural, and radiographic changes that occur over time at intramuscular BMP-9 gene therapy treatment sites. Several members of the bone morphogenetic protein (BMP) family have the potential to induce osteochondrogenesis when the protein is delivered to rodents, canines, rabbits, and nonhuman primates. Previous studies have also demonstrated that BMP gene therapy utilizing adenoviral vectors can also stimulate orthotopic and heterotopic bone formation in rodents and rabbits. Athymic nude and Sprague-Dawley rats were injected with Ad-BMP-9 or Ad-beta-Gal (3.75 x 10(9) particles) in their thigh musculature and light microscopic, electron microscopic, and computerized tomography analysis was performed 3, 6, 9, 12, 15, 18, 21, and 100 days later. To assess early mesenchymal cell proliferation, a bromodeoxyuridine (BrdU) immunohistochemical analysis was also performed 48, 60, and 72 hr postinjection in athymic nude rats. All animals demonstrated extensive endochondral bone formation at the Ad-BMP-9 treatment sites within 3 weeks. The Sprague-Dawley rats also exhibited a massive, acute inflammatory infiltrate during the first week. Proliferating mesenchymal stem cells were clearly evident as early as 2 days after treatment, which differentiated into small or hypertrophied chondrocytes during the next week. During the third week, the cartilaginous matrix mineralized and formed woven bone, which converted to lamellar bone by 3 months. No evidence of bone formation was demonstrated at the Ad-beta-Gal injection sites in the athymic nude or Sprague-Dawley rats. In addition, no cellular proliferation was seen at the Ad-beta-Gal treatment sites in the athymic nude animals as assessed by light microscopy and BrdU immunohistochemistry. The extensive bone formation induced by Ad-BMP-9 suggests that BMP gene therapy may have potential utility in the treatment of degenerative, rheumatic, or traumatic bone pathology.

Adenoviridae↗
PubMed2001

Phase I clinical and pharmacogenetic study of weekly TAS-103 in patients with advanced cancer.

PURPOSE: TAS-103 is an inhibitor of both topoisomerase I and II enzymes with broad antitumor activity. It is metabolized to TAS-103-glucuronide (TAS-103-G) predominantly by uridine diphosphate glucuronosyltransferase isoform 1A1 (UGT1A1). We conducted a phase I study to determine the maximum-tolerated dose (MTD) and dose-limiting toxicity (DLT) of TAS-103 when administered on a weekly schedule to patients with advanced cancer. In addition, we evaluated the influence of UGT1A1 genotype on the pharmacokinetics and toxicity of TAS-103. PATIENTS AND METHODS: Thirty-two patients were treated with escalating doses (50 to 200 mg/m(2)) of TAS-103, administered intravenously over 1 hour each week for 3 weeks. Pharmacokinetic analysis was performed at the 130-, 160-, and 200-mg/m(2) dose levels. UGT1A1 genotypes were determined using reverse-transcription polymerase chain reaction techniques. RESULTS: DLT (grade 3 neutropenia) was observed in 5 of 12 patients at 160 mg/m(2) and in 3 of 6 patients at 200 mg/m(2). At 160 mg/m(2), there was a significant correlation between areas under the curve (AUCs) for TAS-103 and TAS-103-G (r = 0.76, P <.05) and an apparent relationship between TAS-103 AUC and D 15 absolute neutrophil count (r = -0.63, P <.05, n = 11, one outlier excluded). UGT1A1 genotype did not influence clearance of TAS-103. CONCLUSION: We recommend a dose of 130 to 160 mg/m(2), or 250 to 300 mg administered using the above weekly schedule for phase II studies. Further studies to characterize the pharmacodynamics and pharmacogenetics of TAS-103 are warranted.

Adult↗
PubMed2001

pH regulates cation selectivity of poly-(R)-3-hydroxybutyrate/polyphosphate channels from E. coli in planar lipid bilayers.

Poly-(R)-3-hydroxybutyrate/polyphosphate (PHB/polyP) complexes, whether isolated from the plasma membranes of bacteria or prepared from the synthetic polymers, form ion channels in planar lipid bilayers that are highly selective for Ca(2+) over Na(+) at physiological pH. This preference for divalent over monovalent cations is attributed to a high density of negative charge along the polyP backbone and the higher binding energies of divalent cations. Here we modify the charge density of polyP by varying the pH, and observe the effect on cation selectivity. PHB/polyP complexes, isolated from E. coli, were incorporated into planar lipid bilayers, and unitary current-voltage relations were determined as a function of pH. When Ca(2+) was the sole permeant cation, conductance diminished steadily from 97 +/- 6 pS at pH 7.4 to 47 +/- 3 pS at pH 5.5. However, in asymmetric solutions of Ca(2+) and Na(+), there was a moderate increase in conductance from 98 +/- 4 at pH 7.4 to 129 +/- 4 pS at pH 6.5, and a substantially larger increase to 178 +/- 6 pS at pH 5.6, signifying an increase in Na(+) permeability or disorganization of channel structure. Reversal potentials point to a sharp decrease in preference for Ca(2+) over Na(+) over a relatively small decrease in pH. Ca(2+) was strongly favored over Na(+) at physiological pH, but the channels became nonselective near the pK(2) of phosphate (approximately 6.8), and displayed weak selectivity for Na(+) over Ca(2+) at acidic pH. Evidently, PHB/polyP complexes are versatile ion carriers whose selectivity may be modulated by small adjustments of the local pH. The results may be relevant to the physiological function of PHB/polyP channels in bacteria and the role of PHB and polyP in the Streptomyces lividans potassium channel.

Calcium↗
PubMed2001

The evolution of human group B rotaviruses.

The largest reported rotavirus epidemic affected well over a million people in China during 1982-83 and was caused by the adult diarrhoea rotavirus (ADRV), a serogroup B rotavirus. However, ADRV has not been reported outside China since the last recorded small outbreak there in 1987. Here we present evidence that offers an explanation for the sudden appearance and disappearance of the epidemic ADRV strain.

China↗