Publications by authors named "Prabhakar P"

The cystic fibrosis transmembrane conductance regulator (CFTR) is an anion channel in the ATP-binding cassette (ABC) transporter family. CFTR consists of two transmembrane domains, two nucleotide-binding domains (NBD1 and NBD2), and a regulatory domain. Previous biochemical reports suggest NBD1 is a site of stable nucleotide interaction with low ATPase activity, whereas NBD2 is the site of active ATP hydrolysis.

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A recurring obstacle for structural genomics is the expression of insoluble, aggregated proteins. In these cases, the use of alternative salvage strategies, like in vitro refolding, is hindered by the lack of a universal refolding method. To overcome this obstacle, fractional factorial screens have been introduced as a systematic and rapid method to identify refolding conditions.

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Background: Tertiary care hospitals are a potential source for development and spread of bacterial resistance being in the loop to receive outpatients and referrals from community nursing homes and hospitals. The liberal use of third-generation cephalosporins (3GCs) in these hospitals has been associated with the emergence of extended-spectrum beta- lactamases (ESBLs) presenting concerns for bacterial resistance in therapeutics. We studied the 3GC utilization in a tertiary care teaching hospital, in warded patients (medical, surgical, gynaecology, orthopedic) prescribed these drugs.

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Background: Antibiotic overuse and misuse for upper respiratory tract infections in children is widespread and fuelled by public attitudes and expectations. This study assessed knowledge, beliefs, and practices regarding antibiotic use for these paediatric infections among children's caregivers' in Trinidad and Tobago in the English speaking Caribbean.

Methods: In a cross-sectional observational study, by random survey children's adult caregivers gave a telephone interview from November 1998 to January 1999.

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Extended-spectrum beta-lactamase (ESBL) mediated resistance to third generation cephalosporins, amongst the family Enterobacteriaceae, is emerging worldwide. This is the Caribbean's first survey on ESBL production, and was conducted during two six-month periods in 1998 and 2001, in a tertiary health institution in Trinidad and Tobago. Consecutive ampicillin resistant isolates of the family Enterobacteriaceae from in-patients were screened for resistance to third generation cephalosporins, and for ESBL production.

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Objective: To determine the general public's perceptions and use of antibiotics in Trinidad and Tobago, a two-island republic in the Caribbean.

Methods: This prospective study surveyed 824 randomly selected households listed in the telephone directory, from November 1998 to January 1999. Through telephone interviews we determined knowledge about antibiotics and beliefs concerning their safety and efficacy.

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Sexual behavioural factors associated with gonococcal infection among 991 STD clinic attenders in Trinidad, West Indies (WI) were determined by univariate and stepwise multiple logistic regression analysis. Casual sex (odds ratios [OR] 1.6) was the only predictor of gonorrhoea.

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We determined the prevalence of Neisseria gonorrhoeae and describe sociodemographic factors, knowledge and sexually transmitted disease (STD) history associated with gonococcal infection among 991 STD clinic attenders in Trinidad, West Indies (WI). The prevalence of gonorrhoea was 25%. Predictors for gonorrhoea were: male gender (odds ratios [OR] 3.

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We tested the susceptibility patterns of 128 N. gonorrhoeae isolates to six antimicrobials; penicillin, tetracycline, spectinomycin, ceftriaxone, ciprofloxacin and azithromycin, and examined whether certain demographic or behavioral factors related to antibiotic use increased the likelihood of infection by a resistant strain. There was a low rate of resistance to penicillin; penicillinase-producing and chromosomal-mediated penicillin resistant gonorrhea were estimated to be 0.

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The purpose of this study was to determine the prevalence and to assess the efficacy of a single one gram oral dose of azithromycin under direct observed therapy of genital discharge due to Neisseria gonorrhoeae and Chlamydia trachomatis infections in STD clinic attenders in Trinidad and Tobago. All patients with genital discharge and their contacts were given one gram oral dose of azithromycin under direct supervision after collection of urethral and cervical swabs for N gonorrhoeae culture and smear and for C trachomatis antigen detection by ELISA. Clinical and microbiological evaluation was done on those who returned after 7-10 days for follow-up.

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Objective: We evaluated the incidence and organ distribution of arterial extravasation identified using contrast-enhanced helical CT in patients who had sustained abdominal visceral injuries and pelvic fractures after blunt trauma.

Subjects And Methods: Five hundred sixty-five consecutive patients from four level I trauma centers who had CT scans showing abdominal visceral injuries or pelvic fractures were included in this series. The presence or absence of arterial extravasation, as well as the anatomic sites of arterial extravasation, was noted.

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Background: The percentage of Neisseria gonorrhoeae isolates resistant to antimicrobial agents commonly used for treatment is unknown in many Caribbean countries.

Goal: To determine the antimicrobial susceptibility of N gonorrhoeae isolates from Trinidad (144 isolates), Guyana (70 isolates), and St. Vincent (68 isolates) so baseline data can be established for further studies, and to assist in establishing effective treatment guidelines.

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A prospective case-control study involving 46 case patients and 92 age- and neighborhood-matched control subjects was conducted in Trinidad and Tobago (T&T) between March 1998 and May 1999 to determine the etiology, sources, and risk factors for Salmonella enteritidis (SE) infection. SE infection in T&T was found to be associated with the consumption of shell eggs, and in particular raw or undercooked eggs. SE isolates from 30 (88%) of 34 patients and from 9 implicated egg or egg-containing food samples were phage type 4.

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The endothelial nitric-oxide synthase (eNOS), a key signaling protein, undergoes a series of covalent modifications, including co-translational N-myristoylation at Gly(2), as well as post-translational thiopalmitoylation at Cys(15) and Cys(26). Myristoylation of eNOS is required for the subsequent palmitoylation of the enzyme, and both acylations are required for the efficient subcellular targeting of eNOS to plasmalemmal caveolae. We constructed chimeric cDNAs encoding proteins comprised of various acylation-deficient eNOS mutants fused at their N termini to the hydrophobic transmembrane domain of the glycoprotein CD8 and characterized these constructs in transient transfection experiments in COS-7 cells.

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A homograft valve bank for cryopreservation of cardiac homografts was established at the Institute of Cardiovascular Diseases in July 1995. From July 1995 to February 1999, 169 donor hearts were processed. All except four hearts were procured post mortem.

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Rate studies using phosphoglycerate kinase (PGK)--glyceraldehyde-3-phosphate dehydrogenase (GPDH) enzyme pair have been carried out to distinguish between the two mechanisms of intermediate metabolite transfer, namely diffusion through the solvent versus "substrate channelling" within an enzyme-enzyme complex. A procedure has been described for the assay of the rates of PGK-catalysed and the PGK-GPDH coupled reactions at high (saturating) GPDH concentration. With PGKs of rabbit muscle and yeast, the coupled reaction proceeded faster than the PGK-catalysed reaction.

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The endothelial isoform of NO synthase (eNOS) is targeted to sphingolipid-enriched signal-transducing microdomains in the plasma membrane termed caveolae. Among the caveolae-targeted sphingolipids are the ceramides, a class of acylated sphingosine compounds that have been implicated in diverse cellular responses. We have explored the role of ceramide analogues in eNOS signaling in cultured bovine aortic endothelial cells (BAEC).

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Although estrogen is known to stimulate nitric oxide synthesis in vascular endothelium, the molecular mechanisms responsible for this effect remain to be elucidated. Using quantitative immunofluorescence imaging approaches, we have investigated the effect of estradiol on the subcellular targeting of endothelial nitric oxide synthase (eNOS) in bovine aortic endothelial cells. In unstimulated endothelial cells, eNOS is predominantly localized at the cell membrane.

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At pH 7.05 NADH-X prepared by incubating NADH with glyceraldehyde-3-phosphate dehydrogenase (E.C.

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The aim of this study was to determine whether the contents of farm eggs in Trinidad are contaminated with Salmonella and if transovarian transmission occurs. 750 fresh eggs from 10 farms supplying 75% of the country's eggs were cultured for Salmonella. Salmonella was found on the egg shells' surfaces from all farms, and in the egg contents from three farms.

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