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S Shastri

Publications and source records attributed to S Shastri.

At least 19 recordsLinked to original sources

Diagnosing and managing cystic fibrosis in the developing world.

Cystic fibrosis (CF), earlier believed to be non existent in non Caucasians, is now a pan ethnic disease, having being reported from various regions of the world over last one decade. Apart from limited resources, the major problems in diagnosis and management of CF in developing countries include: lack of awareness among pediatricians, absence of facilities for diagnosis (sweat chloride estimation and genetic studies), lack of trained manpower for care of specific problems, and non availability of appropriate drugs. Care of children with CF may not be a priority for governments in countries where childhood mortality rates are high, predominantly due to acute infections. An indigenously developed and relatively inexpensive method of sweat collection and chloride estimation using pilocarpine iontophoresis and titration, respectively, may be an alternative to the commercially available costly equipment. Having a team of trained nurse, physiotherapist, and dietician for optimal care of CF patients may not be feasible due to inadequate resources. Training a single person (e.g. nurse) to deliver comprehensive CF care may be a feasible alternative. To overcome problems of non availability of appropriate drugs (enzymes, inhaled antibiotics, DNAse, etc), locally available drugs may be used. Examples include use of hypertonic saline in place of DNAse, enteric coated enzyme tablets in place of enteric coated spherules, etc. Factors that are associated with decreased survival in CF patients from developing countries are age of onset of symptoms <2 months, severe malnutrition at the time of diagnosis, colonization with Pseudomonas at the time of diagnosis and frequency of pneumonia >4 episodes/year. All these factors can be modified except onset of symptoms before 2 months of age, by early diagnosis and appropriate treatment. Many of the above mentioned hurdles have been successfully overcome by us to establish CF services in a resource-limited setting. We conclude that education of pediatricians about the disease, early diagnosis using indigenous technology and aggressive physiotherapy with nutritional management and judicious use of antibiotics can improve the quality of life and survival in CF patients in resource-limited settings.

Anti-Bacterial Agents↗

Accuracy of conventional cytology: results from a multicentre screening study in India.

OBJECTIVE: We conducted a multi-centre cross-sectional study in India to evaluate the accuracy of conventional cytology to detect high-grade squamous intraepithelial lesions (HSIL). SETTING: Cross-sectional studies in Jaipur, Kolkata, Mumbai and Trivandrum, India, during 1999-2003. METHODS: A common protocol and questionnaire were used to test 22,663 women aged 25-65 years with conventional cytology in five cross-sectional studies. Three thresholds were used to define test positivity: atypical squamous cells of uncertain significance (ASCUS), low-grade squamous intra-epithelial lesion (LSIL), or HSIL. All screened women were investigated with colposcopy, and biopsies were taken when necessary. The reference standard for final disease status was histology or negative colposcopy. Data from the studies were pooled to evaluate the test characteristics for the detection of histologically confirmed HSIL. RESULTS: The test positivity rates of cytology were 8.8% at ASCUS, 6.2% at LSIL and 1.8% at HSIL thresholds, and 355 women had histologically confirmed HSIL while 74 had invasive cancer. The pooled sensitivity, specificity, positive and negative predictive values at ASCUS threshold were 64.5%, 92.3%, 11.8% and 99.4% respectively. The corresponding values at LSIL threshold were 58.0%, 94.9%, 15.2% and 99.3%, while at the HSIL threshold they were 45.4%, 99.2%, 46.3% and 99.1%. The sensitivity varied between 37.8-81.3% at ASCUS, 28.9-76.9% at LSIL and 24.4-72.3% at HSIL thresholds. A significantly low sensitivity was observed in women aged 25-39 years (p<0.001). The wide variation in sensitivity across study sites persisted even after age standardisation. CONCLUSION: The sensitivity of cytology varied widely between the study sites. Findings from our study and other reviews indicate that sustained efforts in improving sampling, preparation and reading of cytological specimens and improvements in clinical judgement are essential to achieve concurrently high sensitivity and specificity.

Adult↗

Early detection of cervical cancer with visual inspection methods: a summary of completed and on-going studies in India.

India is a high-risk country for cervical cancer which accounts a quarter (126,000 new cases, 71,000 deaths around 2,000) of the world burden. The age-standardized incidence rates range from 16-55 per 100,000 women in different regions with particularly high rates in rural areas. Control of cervical cancer by early detection and treatment is a priority of the National Cancer Control Programme of India. There are no organized cytology screening programmes in the country. The technical and financial constraints to organize cytology screening have encouraged the evaluation of visual inspection approaches as potential alternatives to cervical cytology in India. Four types of visual detection approaches for cervical neoplasia are investigated in India: a) naked eye inspection without acetic acid application, widely known as 'downstaging'; b) naked eye inspection after application of 3-5% acetic acid (VIA); c) VIA using magnification devices (VIAM); d) visual inspection after the application of Lugol's iodine (VILI). Downstaging has been shown to be poorly sensitive and specific to detect cervical neoplasia and is no longer considered as a suitable screening test for cervical cancer. VIA, VIAM and VILI are currently being investigated in multicentre cross-sectional studies (without verification bias), in which cytology and HPV testing are also simultaneously evaluated, and the results of these investigations will be available in 2003. These studies will provide valuable information on the average, comparative test performances in detecting high-grade cervical cancer precursors and cancer. Results from pooled analysis of data from two completed studies indicated an approximate sensitivity of 93.4% and specificity of 85.1% for VIA to detect CIN 2 or worse lesions; the corresponding figures for cytology were 72.1% and 91.6%. The efficacy of VIA in reducing incidence of an mortality from cervical cancer and its cost-effectiveness is currently being investigated in two cluster randomized controlled intervention trials in India. One of these studies is a 4-arm trial addressing the comparative efficacy of VIA, cytology and primary screening with HPV DNA testing. This trial will provide valuable information on comparative detection rates of CIN 2-3 lesions by the middle of 2003. The expected outcomes from the Indian studies will contribute valuable information for guiding the development of public health policies on cervical cancer prevention in countries with different levels of socio-economic and health services development and open up new avenues of research. This paper is available too at: http//www.insp.mx/salud/index.html.

Acetic Acid↗

Clinical profile and frequency of delta f508 mutation in Indian children with cystic fibrosis.

OBJECTIVE: To document clinical profile of cystic fibrosis (CF) in Indian children and the prevalence of delta F508 mutation in these patients. DESIGN: Observational study. SETTING: Pediatric chest clinic in an urban tertiary care center in north India. PERIOD OF STUDY: July 1995 to June 2002. METHODS: Clinical features of 120 children diagnosed as CF by quantitative pilocarpine iontophoresis were recorded. A polymerase chain reaction based test for identification of delta F 508 mutation was performed on all children. RESULTS: Out of 3500 new cases registered in Pediatric Chest Clinic during this period 120, (3.5%) children were diagnosed as CF. Origin of parents of patients traced from almost all the States of north India. Family history suggestive of CF was present in 41 (34%) and consanguinity in 19 (61%) patients. Common clinical manifestations at the time of presentation included recurrent or persistent pneumonia in 118 (98%), failure to thrive in 108 (90%), malabsorption in 96 (80%), history of meconium ileus in 10 (8%), and rectal prolapse was present in 16 (13%). History of salt craving, salty taste on kissing and skin rashes was present in 5 patients each. 49(41%) patients were severely malnourished. Nasal polyposis was present in 5 (4%) patients. Examination of chest revealed evidence of hyperinflation in 100 (83%), kyphosis 20 (17%), crepitations 110 (92%), wheezing 40 (25%) and bronchial breathing in 20 (17%) patients. Average clinical CF scores were 51 (95%; CI 20-80). 48 (40%) patients had a CF score of LT40. Pseudomonas spp was cultured from respiratory secretions of 51 (42%), Staphylococcus spp in 18 (15%), Klebsiella spp in 8 (7%) and Hemophilus influenzae in 2 (2%) patients. Delta F508 mutation was positive in 45 chromosomes out of 240 tested. Patients originated from Pakistan had more frequency of delta F508 mutations. CONCLUSIONS: Cystic fibrosis does occur in Indian children; clinical features are classical. Diagnosis is often delayed and the disease is advanced in most patients at the time of diagnosis. Frequency of Delta F508 mutation is 19% i.e., less than that seen in Caucasian population. There is need to create awareness about occurrence of CF in Indian children.

Child↗

An indigenously developed method for sweat collection and estimation of chloride for diagnosis of cystic fibrosis.

An indigenously developed method for sweat collection and titration method for estimation of chloride was validated. The mean difference in estimated chloride value from the known strength of saline in 50 samples was -1.04 +/- 4.13 mEq/L (95% CI: -0.07 to 2.28). The mean difference in the estimated chloride values between two observers when the test was performed on known strengths of saline solution was -2.5 +/- 4.24 mEq/L (95% CI: -3.67 to 1.33). The inter observer variability between two observers when the test was performed on sweat samples obtained from 50 individuals was -1.12 +/- 4.34 mEq/L (95% CI: -2.23 to 0.8 ). Sweat weight of more than 100 mg could be collected in first attempt in 602 of 757 (80%) patient with an average sweat weight of 230 mg. This inexpensive method of sweat collection and chloride estimation has acceptable accuracy and repeatability and can be used in resource poor setting for making a diagnosis of cystic fibrosis.

Cystic Fibrosis↗

Cysteinyl leukotrienes mediate enhanced vasoconstriction to angiotensin II but not endothelin-1 in SHR.

We assessed whether cysteinyl leukotrienes mediate the vasoconstrictor responses to angiotensin II and endothelin-1 in the mesenteric vascular bed of Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) perfused ex vivo at a constant flow rate of 5 ml/min with Krebs buffer. Maximal perfusion pressure response (E(max)) but not EC(50) values to angiotensin II (P < 0.001) and endothelin-1 (P < 0.01) were significantly higher in the SHR, whereas the responses to potassium chloride remained unchanged. Inclusion of the selective 5-lipoxygenase inhibitor AA-861 or the cysteinyl leukotriene receptor antagonist MK-571 significantly reduced the vasoconstrictor responses to angiotensin II but not to endothelin-1 and potassium chloride. The reduction in E(max) to angiotensin II was more pronounced in SHR (P < 0.001) than in WKY (P < 0.05) rats. Cysteinyl leukotrienes LTC(4)-, LTD(4)-, and LTE(4) (1 microM)-evoked vasoconstrictor responses were significantly higher in SHR (P < 0.05), whereas LTB(4) failed to evoke any response in either strain. These data suggest that 5-lipoxygenase metabolites, particularly cysteinyl leukotrienes, contribute to the exaggerated vasoconstrictor responses to angiotensin II but not to endothelin-1.

Angiotensin II↗

Prevalence of astroviruses in a children's hospital.

An enzyme immunoassay for astrovirus was used to screen 357 stool samples from 267 symptomatic inpatients at a tertiary-care children's hospital. Thirty stool samples from 26 patients contained astrovirus antigen, while rotavirus was found in 34 samples and Clostridium difficile toxin was found in 40. Half of the astrovirus infections were nosocomial. Additional pathogens were identified in six of the astrovirus antigen-positive stool samples. Most (80%) of the astroviruses recovered were of serotype 1. Astrovirus infections were significantly more common than rotavirus or C. difficile infections in very young infants and in those with surgical short-bowel syndrome.

Adolescent↗

Relationship among particle size distribution, dissolution profile, plasma values, and anthelmintic efficacy of oxfendazole.

Three mean particle sizes of oxfendazole raw material (1.65 micron, lot A; 3.2 micron, 10t B; 12.0 micron, lot C) were prepared and identically formulated as corresponding (A, B, and C) suspensions at 2.26% (W/V) concentration. Studies involving microscopic examination, scanning electron microscope analysis, particle size distribution, and surface area measurement were carried out on raw materials. In vitro dissolution profiles were obtained for the suspensions. A comparative bioavailability study of these 3 suspensions was performed in 12 sheep with each sheep given each formulation in a Latin square crossover study design; oxfendazole was dosed at rate of 5 mg/kg of body weight. Plasma-value measurements were made followed by an analysis of various bioavailability studies. Plasma area values indicated that suspension C (dw = 12.0 micron) was significantly (P less than 0.05) less bioavailable than was suspension A (dw = 1.65 micron); there was no difference between suspension A and suspension B. Significant differences were not seen in biological half-life and maximum plasma concentrations. The term dw refers to that particle diameter (determined by Coulter counting) at which 50% of the oxfendazole mass was in the form of particles having a lesser diameter and 50% was in the form of particles having a greater diameter. In a separate study involving 20 Merino weaner sheep infected with benzimidazole-resistant Haemonchus contortus larvae, oxfendazole's anthelmintic efficacy was demonstrated in the 2.26% suspension dosage form (90% particles less than 10 micron) at a dosing rate of 5 mg/kg. A correlation was found between its anthelmintic activity and plasma area values when compared in individual sheep. Data demonstrated that substantial differences in particle size distribution of oxfendazole could influence its dissolution rate, plasma concentrations, and absorption characteristics, thus indicating that oxfendazole's absorption could be dissolution-rate limited.

Administration, Oral↗