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Biomedical subjects

S H Shah

Publications and source records attributed to S H Shah.

At least 19 recordsLinked to original sources

Influence of gender on outcomes after intra-arterial thrombolysis for acute ischemic stroke.

Recent data suggest that women obtain greater benefit than men from IV fibrinolysis for acute ischemic stroke. It is unknown whether this gender-thrombolysis advantage extends to those treated with intra-arterial (IA) thrombolysis. The authors evaluated the independent effect of gender among ischemic stroke patients treated with IA fibrinolysis and found no differences in short-term clinical and angiographic outcomes between men and women who received IA thrombolysis for acute ischemic stroke.

Aged↗

Serum lipids in the GENECARD study of coronary artery disease identify quantitative trait loci and phenotypic subsets on chromosomes 3q and 5q.

Coronary artery disease (CAD) and dyslipidemia have strong genetic components. Heterogeneity complicates evaluating genetics of complex diseases such as CAD; incorporating disease-related phenotypes may help reduce heterogeneity. We hypothesized that incorporating lipoproteins in a study of CAD would increase the power to map genes, narrow linkage peaks, identify phenotypic subsets, and elucidate the contribution of established risk factors to genetic results. We performed ordered subset analysis (OSA) and quantitative trait linkage (QTL) using serum lipoproteins and microsatellite markers in 346 families with early-onset CAD. OSA defined homogeneous subsets and calculated lod scores across a chromosome after ranking families by mean lipoprotein values. QTL used variance components analysis. We found significantly increased linkage to chromosome 3q13 (LOD 5.10, p = 0.008) in families with higher HDL cholesterol, lower LDL and total cholesterol, lower triglycerides, and fewer CAD risk factors, possibly due to a concentrated non-lipoprotein-related genetic effect. OSA identified linkage on chromosome 5q34 in families with higher cholesterol, possibly representing a hereditary lipoprotein phenotype. Multiple QTLs were identified, with the strongest for: total cholesterol on chromosome 5q14 (LOD 4.3); LDL on 20p12 (LOD 3.97); HDL on 3p14 (LOD 1.65); triglycerides on 18q22 (LOD 1.43); and HDL/TC ratio on 3q27-28 (LOD 2.06). Our findings suggest the presence of etiologic heterogeneity in families with early-onset CAD, potentially due to differential effects of lipoprotein phenotypes. Candidate genes are under investigation.

Adult↗

Environmental monitoring of benzene and toluene produced in indoor air due to combustion of solid biomass fuels.

Exposure to benzene and toluene from the combustion of solid biomass fuels is one of the important causes of morbidity and mortality in developing countries. In this study, we assessed the exposure of cooks to benzene and toluene from biomass fuel combustion in 55 rural homes. The GC-MS was used for quantification while a personnel sampler was used for environmental monitoring. The benzene exposure differed significantly (p < 0.0001) across different types of indoor kitchen fuel combinations. The geometrical mean (GM) of benzene exposure for cooks during cooking hours in an indoor kitchen using mixed fuel was 75.3 microg/m3 (with partition) and 63.206 microg/m3 (without partition), while the exposure was 11.7 microg/m3 for open type. The benzene exposure was significantly higher (p < 0.05) in an indoor kitchen with respect to open type using mixed fuels. Concentration of benzene (114.1 microg/m3) for cooks in an indoor kitchen with partition using dung fuel was significantly higher in comparison to non-cooks (5.1 microg/m3) for open type. Benzene exposure was not significantly different for kitchen with ventilation (31.2 microg/m3) and without ventilation (45.0 microg/m3) using wood fuel. However, this value was significantly (p < 0.05) lower than in indoor kitchens with or without partition. An almost similar trend was observed for toluene but the difference was statistically non-significant. This study may be helpful in developing a regional exposure database and in the facilitation of health risk assessment due to volatile organic pollutants in our day-to-day environment.

Air Pollutants↗

Gas chromatographic-mass spectroscopic determination of benzene in indoor air during the use of biomass fuels in cooking time.

A gas chromatography-mass spectroscopic method in electron ionization (EI) mode with MS/MS ion preparation using helium at flow rate 1 ml min(-1) as carrier gas on DB-5 capillary column (30 m x 0.25 mm i.d. film thickness 0.25 microm) has been developed for the determination of benzene in indoor air. The detection limit for benzene was 0.002 microg ml(-1) with S/N: 4 (S: 66, N: 14). The benzene concentration for cooks during cooking time in indoor kitchen using dung fuel was 114.1 microg m(-3) while it was 6.6 microg m(-3) for open type kitchen. The benzene concentration was significantly higher (p < 0.01) in indoor kitchen with respect to open type kitchen using dung fuels. The wood fuel produces 36.5 microg m(-3) of benzene in indoor kitchen. The concentration of benzene in indoor kitchen using wood fuel was significantly (p < 0.01) lower in comparison to dung fuel. This method may be helpful for environmental analytical chemist dealing with GC-MS in confirmation and quantification of benzene in environmental samples with health risk exposure assessment.

Air↗

A correlation of secondary aerosol (nitrate and sulfate) with respirable particulate matter (RPM) in ambient air at different traffic junctions of Vadodara city.

The correlation study of secondary aerosol (nitrate and sulfate) with RPM in ambient air at different traffic junctions of Vadodara city is reported. RPM was analyzed using Ion Chromatography technique and measured the level of nitrate and sulfate in ambient air. The correlation studies of these particulates with RPM have been established. The average concentration of sulfate and nitrate in ambient air was found 35.74 microg/m3 and 24.22 microg/m3, which ranged of 5.33-84.69 and 1.93-77.86 microg/m3 respectively. The correlation of RPM and SO4 (r = 0.813, P<0.01), RPM-NO3 (r = 0.5549, P<0.01) and SO4-NO3 (r = 0.6133, P<0.01) were found significant. The presence of sulfate and nitrate in RPM is 8.25% and 5.60% . The pH of water extract of RPM averaged 6.81, which ranged 6.17-7.28. Regression analysis result showed that the relationship between RPM-SO4 was significantly (R2=0.66215) correlated. This indicate that probably the secondary aerosols such as nitrate and sulfate in excess may cause irritation and increasing lung disease.

Aerosols↗

Susceptibility patterns of Escherichia coli: prevalence of multidrug-resistant isolates and extended spectrum beta-lactamase phenotype.

OBJECTIVE: To study Escherichia coli (E. coli) susceptibility, prevalence of multidrug-resistant isolates and possible role of extended spectrum beta-lactamases (ESBL) in E. coli resistance. SETTING: Department of Medicine, Shifa College of Medicine, Islamabad. METHODS: Three hundred and seventy eight E. coli isolates from different sources were identified during six-month period. Susceptibility to various antibiotics was checked using standard methods. Multidrug-resistant isolates were separated. Isolates resistant to cefpodoxime and aztreonam were considered as ESBL phenotype, indicating ESBL production. RESULTS: Most of isolates were resistant to ampicillin and trimethoprim/sulfamethoxazole. Overall resistance to ciprofloxacin, ceftriaxone, cefotaxime and cefpodoxime was 49%, 34%, 36% and 38% respectively. Resistance to fourth generation cephalosporins was lower. Almost all Isolates were sensitive to amikacin, imipenem and tazobactam. Aztreonam resistance was found in 25% isolates. Similar pattern was observed for urinary E. coli isolates; 45% E. coli isolates were found to be multidrug-resistant. Nitrofurantoin showed low-level resistance both to multidrug-resistant as well as urinary isolates. Resistance to both cefpodoxime and aztreonam was found in 25% isolates suggesting ESBL production. CONCLUSION: E. coli resistance in Pakistan is much higher than reported from western literature. Multidrug-resistant isolates, including third generation cephalosporins and quinolones, are very common. ESBL production may contribute to this high level resistance against beta-lactams.

Adolescent↗

Transjugular intrahepatic portosystemic stent-shunt insufficiency and the role of diabetes mellitus.

BACKGROUND/AIMS: Maintenance of long-term patency of transjugular intrahepatic portosystemic stent-shunts (TIPSS) has proved problematic. Various prognostic variables have been assessed as predictors, but the role of diabetes mellitus, which induces vascular endothelial cell dysfunction, has not been assessed. METHODS: We analysed the records of 248 patients who underwent TIPSS between July 1991 and July 1997, followed-up through to August 1998. Patients with at least one shunt assessment by portography and available blood glucose levels were eligible (177 patients; median follow-up, 15.0 months). Fourteen patients had a pre-procedural diagnosis of diabetes (one insulin dependent, seven oral hypoglycaemic treated and six diet controlled). In another 14 patients, diabetes was diagnosed at TIPSS insertion, giving a 28/177 (15.8%) prevalence of diabetes in our patients. Fifty-nine patients were excluded from the final analysis (including five diabetics), as they either died or had early shunt insufficiency (within 1 month of stent placement), leaving 118 patients (including 23 diabetics) to be included in the final analysis. RESULTS: Mean age, sex distribution, median follow-up (months) and pre-shunt portal pressure gradient were comparable in the two groups (diabetics versus non-diabetics). Child-Pugh classes A and B were more common in the diabetic group (P < 0.01), and the mean inserted stent diameter was larger in the diabetic group (P < 0.05). The presence of diabetes was associated with a higher incidence of delayed shunt insufficiency (P = 0.02), but there was no evidence of an association between presence of diabetes and variceal haemorrhage post TIPSS. Kaplan-Meier analyses revealed earlier insufficiency in diabetic patients compared with those without diabetes (P = 0.04). Age, gender and presence of diabetes are included in the final logistic regression model. Individuals who have diabetes are more likely to experience shunt insufficiency independent of age and gender. CONCLUSIONS: Diabetes mellitus is common in patients undergoing TIPSS and is associated independently with increased incidence of primary delayed shunt insufficiency.

Diabetes Complications↗

Frequency of malignant solid tumors in children.

OBJECTIVE: To find out the frequency of malignant solid tumors in children (< 15 years). SETTING: All cases of pediatric malignant solid tumors which were diagnosed in the section of histopathology at the Aga Khan University Hospital, Karachi during the period of two years. METHODS: These tumors were initially evaluated on H&E stained sections and special stains were also performed whenever indicated. The undifferentiated tumors were evaluated immunohistochemically by using a panel of antibodies on sections from routinely processed, formalin fixed, paraffin embedded tissue blocks. RESULTS: Of two hundred and fifty three (253) consecutive cases of paediatric malignant solid tumors, lymphoma (26.1%) was the most common tumor followed by central nervous system tumors (16.6%), osteosarcoma (7.5%), rhabdomyosarcoma (6.7%), neuroblastoma (5.1%), Wilm's tumor (5.1%), Ewing's sarcoma (4.7%), retinoblastoma (4.7%), germ cell tumor (4.4%) and primitive neuroectodermal tumor (4%) in order of frequency. In seven cases (2.8%), the nature of lesion remained undetermined even after immunohistochemical staining. Rest of malignant tumors (12.3%) included the rare entities like synovial sarcoma, nasopharyngeal carcinoma, leiomyosarcoma, malignant schwannoma and thyroid carcinoma, etc. CONCLUSION: Lymphoma was the most frequent Paediatric tumor. The frequency of childhood central nervous system tumors was quite high as compared to the other series from different regions of Pakistan.

Adolescent↗

Childhood non-Hodgkin's lymphoma: an immunophenotypic analysis.

OBJECTIVE: To observe the frequency of histological subtypes of childhood non-Hodgkin's lymphoma and its immunohistochemical profile. SETTING: All cases of non-Hodgkin's lymphoma diagnosed in children (< 15 years) in the section of histopathology at the Aga Khan University Hospital Karachi during the period of three years. METHODS: These consecutive cases were evaluated on H&E stained sections and then immunohistochemistry analysis of these tumors was performed by employing Peroxidase Anti-Peroxidase (PAP) technique. RESULTS: The present series included 61 cases of non-Hodgkin's lymphoma. NHL was more common in males as compared to females with male to female ratio of 5.8:1. High grade NHL comprised 87% of childhood lymphoma. The mode of presentation in majority of NHL (57%) was extranodal. Burkitt's lymphoma (33%) was the most prevalent histological subtypes, followed by lymphoblastic (28%), diffuse large cell (15%), diffuse mix small and large cell (13%), small non cleaved Non-Burkitt's (7%) and immunoblastic (4%). Immunophenotypic analysis of the childhood Non-Hodgkin's lymphoma revealed that 67% of the Non-Hodgkin's lymphoma are B-cell type while 33%, are those of T-cell lineage. CONCLUSION: NHL was more common in males. Majority of NHL in children were high grade tumors. Burkitt's lymphoma was the most frequent histological subtype. T-cell NHL comprised a significant portion of childhood lymphomas.

Adolescent↗

Morphological pattern of testicular tumors.

OBJECTIVE: To find out the mode of presentation, age distribution and the prevalence of various histological subtypes of testicular tumors. METHOD: All consecutive cases of testicular tumors diagnosed in the department of pathology, the Aga Khan University Hospital, Karachi, during the period of eight years (1991-98) were included in this study. Relevant clinical details such as age, clinical presentation and side of involvement of the testis were also recorded, where available. RESULTS: During the span of eight years (1991-98), 170 cases of testicular tumors were diagnosed at the Aga Khan University Hospital, Karachi. Most of the tumors were diagnosed in the third and fourth decade of life. Scrotal mass or swelling was the predominant mode of presentation. There was a slight predominance of right-sided testicular tumors. Germ cell tumors constituted 83.5% of all malignant testicular neoplasms. Amongst these seminoma was the most common (36.5%) tumor followed by mixed germ cell tumors (28.82%). Yolk-sac tumor was the commonest testicular neoplasm in children while lymphoma was the predominant neoplasm in the elderly population. CONCLUSION: The overall relative frequency of testicular malignancy in this series correlated with that reported in the international literature.

Adolescent↗

Breast carcinoma in Pakistani females: a morphological study of 572 breast specimens.

OBJECTIVE: To study the morphological features in breast carcinoma which have proven prognostic value. METHODS AND SETTING: A retrospective analysis of 572 mastectomy specimens received over a period of three years at the department of pathology, The Aga Khan University Hospital. RESULTS: A total of 572 mastectomy specimens were analyzed which were received over a period of three years. Most of the patients were in the 5th and 6th decades of life. The mean age at diagnosis was 48 years. The most common tumour was infiltrating ductal carcinoma (81%). Tumour size was > 2 cms. in 80% of the cases. According to Modified Bloom and Richardson system most of the tumours were in grade II (65%) followed by grade III (24%). The number of cases with > 3 lymph node metastasis was significantly higher (70%) in tumours of > 2 cms size. High grade tumours also showed increased number of lymph node involvement. CONCLUSION: In Pakistani females breast carcinoma occurs at a younger age group. They are of large size at the time of presentation and show more frequent axillary lymph node metastasis. Infiltrating ductal carcinoma is the most common type of tumour with predominance of high grade lesions.

Adult↗

Association of Epstein Barr Virus (EBV) with nasopharyngeal carcinoma (NPC).

AIM: To observe the frequency of nasopharyngeal carcinoma (NPC) and its association with Epstein Barr Virus (EBV) infection. SETTING: This study included consecutive cases of nasopharyngeal carcinoma, which were diagnosed in the Department of Pathology at the Aga Khan University Hospital, Karachi in the period of two years (1996-97). METHODS: These tumors were initially evaluated on H&E stained sections. The tumors showing evidence of keratinization were excluded from the study. The Epstein Barr Virus was detected with the help of Polymerase chain reaction in formalin fixed, paraffin embedded tissue sections. RESULTS: During the study period, seventeen cases of nasopharyngeal carcinoma were diagnosed which comprised 0.3% of all malignant tumors. The age ranged from 5 years to 70 years with male to female ratio of 2.4:1. The NPC was more prevalent in adults (71%) as compared to children (29%) under 15 years. Six cases (35%) exhibited positive signal for Epstein Barr Virus. CONCLUSION: Nasopharyngeal carcinoma is an infrequent tumor. The prevalence of Epstein Barr virus infection in nasopharyngeal carcinoma is quite low as compared to other regions of the world.

Adolescent↗

Nocturnal sweating and temperature in depression.

OBJECTIVE: Patients with depression may have altered thermoregulation, such as high nocturnal core temperatures, decreased daytime sweating and subjective complaints of nocturnal sweating. We sought to compare nocturnal sweating in depressed patients and non-depressed controls, and to assess the impact of REM sleep on sweat rates. METHOD: Nocturnal sweat rate, nocturnal temperature and REM sleep were measured during the night in 9 controls and 8 depressed subjects; 7 depressed patients were assessed during recovery. RESULTS: The nocturnal temperature was significantly higher in depressed patients compared to controls, and decreased significantly with recovery. The nocturnal sweat rates of depressed patients did not differ significantly from those of controls, but decreased significantly with recovery. Analyses of sweat rates before, during and after REM sleep indicated a trend for the entire sample to show a decrease in sweat rates during REM. CONCLUSION: The nocturnal sweating rates in the depressed patients suggest that impaired sweating is not the cause of the high nocturnal temperature commonly found in depressed patients.

Adult↗

Clinico-morphological pattern of intracranial tumors in children.

OBJECTIVE: The objective of present study was to observe the histopathological pattern of intracranial tumors in children (< 15 yrs) and to correlate the site of lesion along with the histological diagnosis. SETTING: The study included consecutive cases of intracranial tumors diagnosed in children (< 15 yrs.) in the section of histopathology at the Aga Khan University Hospital, Karachi during the period of three years. METHODS: The initial histological evaluation of these lesions was performed on H and E stained section of paraffin embedded tissue. Special stains and immunohistochemical analysis was done whenever indicated. RESULTS: During the study period, fifty-four cases of intracranial tumors were diagnosed in children. The age ranged from 1-1/2 years to 4 years with male to female ratio of 1.1:1. Astrocytoma comprised 39% of all intracranial tumors of childhood. Medulloblastoma (18.6%) ranked the second most prevalent brain tumor followed by empendymoma (13%), oligodendroglioma 7.5% while non-Hodgkin's lymphoma, primitive neuroblastoma 3.7% and ganglioglioma 3.7% while non-Hodgkin's lymphoma, primitive neuroectodermal tumors, mixed germ cell tumor, pineoblastoma, choroid plexus carcinoma and malignant meningioma constituted 1.8% each. CONCLUSION: Astrocytoma was the most common pediatric brain tumor. Medulloblastoma was more common in males while pilocytic astrocytoma was more frequent in females. Posterior cranial fossa was the most common site (43.5%) of pediatric brain tumors. Low grade astrocytoma was more prevalent in posterior cranial fossa as compared to high grade astrocytoma which was more frequent in the supratentorial region.

Astrocytoma↗