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Biomedical subjects

A Kumar

Publications and source records attributed to A Kumar.

At least 1,045 records · Page 58Linked to original sources

Inherited liver diseases in adults.

Important inherited disorders causing acute and chronic liver disease include hemochromatosis, Wilson's disease, alpha 1-antiprotease (antitrypsin) deficiency, and cystic fibrosis. The detection of an index case has implications for screening family members. A normal life span can be expected with treatment in asymptomatic patients with Wilson's disease and hemochromatosis. We present a clinical approach to disease recognition, investigation, and screening.

Adult↗

Regulation of fibrin deposition by malignant mesothelioma.

Malignant mesothelioma (MM) is a locally aggressive tumor that spreads by poorly understood mechanisms. Because neoplastic spread has been linked to altered fibrin turnover, we used immunohistochemistry of nine MM and three fibrous tumors of the pleura to confirm in vivo fibrin deposition and expression of selected coagulation and fibrinolytic reactants in MM. Tumor-associated fibrin was readily detectable at site of tissue invasion. Little fibrin was distributed within the tumor, but tissue factor and tissue factor pathway inhibitor, urokinase, urokinase receptor, and plasminogen activator inhibitors 1 and 2 were all detected in either epithelioid or sarcomatous areas of MM. We used the MS-1 human pleural mesothelioma cell line to determine how expression of these reactants is regulated. Fibrinolytic activity of MS-1 is mainly due to urokinase and is responsive to cytokine stimulation. Functional extrinsic activation and prothrombinase complexes assemble at the cell surface. MM express procoagulants as well as fibrinolytic reactants in vivo and in vitro that promote local fibrin formation and remodeling. Fibrin deposition occurs primarily at areas of tissue invasion and could promote local extension of this neoplasm. Sparsity of fibrin within the central portions of the tumor stroma suggests that local resorption of transitional fibrin occurs at sites of established MM.

Blood Coagulation↗

Radiological predictors of response to renovascular reconstructive surgery.

The aim of this study was to identify preoperative angiographic criteria which could be used to predict the response to renovascular reconstruction. A cohort of 49 patients who survived for more than 6 months after renovascular reconstruction was studied. All preoperative angiograms were reviewed independently and the renal size, degree of stenosis and the length of the lesion recorded. The response of blood pressure and renal function to surgery were correlated with the angiographic findings. We found that 58% of patients had long-term improvement in blood pressure control, though the response was significantly better where both kidneys were >12 cm in size (82%) compared with when both kidneys were < 12 cm (25%), P < 0.02. The degree of stenosis, while showing a trend towards a better blood pressure response with increasing stenosis, was not a statistically significant factor. None of the angiographic criteria examined could be used to predict the response in renal function. We have shown that the preoperative renal size is the only angiographic factor that may have some role in predicting the response of blood pressure to renovascular reconstruction.

Adult↗

Teachers' awareness and opinion about AIDS: implications for school based AIDS education.

Two hundred thirteen teachers of one secondary and four primary schools of East Delhi were interviewed to assess their knowledge and attitudes about AIDS and their opinions regarding school based AIDS education. Observations revealed that majority of the teachers were aware of various aspects of HIV/AIDS. However, they also had some misconceptions regarding transmission of the disease. Though, most of the teachers opined that they could play an important role in educating the students as well as the community regarding AIDS/STDs, three fourths of them had never discussed AIDS/STDs with their students. Majority of teachers were in favour of starting class room based education on AIDS/STDs, beginning from secondary classes onwards, and more than half opined that class teacher could educate the students better than the doctors or parents. The results suggest that after being properly trained, teachers can be effectively utilized for educating the students.

Acquired Immunodeficiency Syndrome↗

Patients' perception of health on renal replacement therapy: evaluation using a new instrument.

Patients' perception of their health is an important outcome measure in the management of chronic disease. Comparing that perception from patients receiving different forms of renal replacement therapy (RRT) with data from the general population could be used to monitor the effectiveness of treatment. The short form 36 (SF-36) questionnaire is a general measure of health status which has been validated in the UK and uses eight health scales comprising physical function, social function, role limitation (physical and emotional), mental health, energy, pain and overall health. Using the SF-36 questionnaire, the perception of health of patients receiving RRT was compared with data from healthy control subjects. One hundred and seventy-two of 185 (93%) patients receiving RRT--transplant (n = 102), haemodialysis (n = 43), and peritoneal dialysis (n = 27) completed the questionnaire; scores were compared with those from 542 healthy control subjects. The perception of health of haemodialysis and peritoneal dialysis patients was significantly worse than transplanted patients and controls in six of the eight scales (P < 0.05 dialysis versus transplant and controls). That of transplanted patients was worse in only two and better in one of the eight scales compared with the general population (P < 0.05). Patients were also stratified into low, medium, and high-risk groups based on age and comorbidity and were analysed irrespective of treatment modality. Scores were significantly different across the risk groups in five of the eight scales. We conclude that the SF-36 questionnaire is acceptable to patients on RRT and enables the perception of health of patients receiving RRT to be compared with that of the general population.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

CD44 isoforms containing exons V6 and V7 are differentially expressed on mitogenically stimulated normal and Epstein-Barr virus-transformed human B cells.

CD44, a cell adhesion molecule, exists in multiple isoforms that are generated by RNA alternative splicing. CD44 isoforms containing exon V6 (CD44 V6) have been associated with tumorigenesis and metastasis. We investigated the association between human B-cell activation and CD44 V6 isoform expression by analysing its expression in resting and mitogenically stimulated B cells. Results showed that resting B cells expressed the CD44 H (no variable exon) isoform alone. Activation of B cells [phorbol myristate acetate (PMA), surface immunoglobulin cross-linking alone or in the presence of interleukin-2 (IL-2)] induced CD44E (variable exon V8-10), R2 (VIO) and CD44 isoforms containing exons V6 and/or V7 (CD44 V6/V7). Epstein-Barr virus (EBV) infection of B cells, an alternative method of B-cell activation, induced the expression of CD44 E and R2 but not CD44 V6/V7. These results indicate that CD44 V6/V7 expression depends on the mode of activation. CD44 isoform expression was also investigated in a panel of EBV-negative and EBV-positive Burkitt's lymphoma (BL) B-cell lines. EBV-negative BL cells did not express CD44. In contrast, EBV-positive BL cells expressed CD44 H, R2 and E but not CD44 V6/V7 isoforms, suggesting an association between EBV infection and CD44 isoform induction. To determine directly the role of EBV in CD44 isoform induction, an EBV-negative BL cell line, BL30 (negative for all isoforms of CD44), BL30 infected in vitro with the EBNA-2-defective P3HR1 (BL30/P3HR1), and the wild-type B95-8 strain of EBV (BL30/B95-8) were examined. The parental BL30 cells infected with the wild-type EBV strain, but not with the P3HR-1 strain, expressed CD44 H, R2 and E isoforms, as seen in EBV-immortalized B cells. These studies suggest that (1) alternative splicing of CD44 isoforms is differentially regulated depending on the mode and state of cell activation, and that (2) the CD44 V6/V7 isoforms may represent B-cell activation antigens that are induced by mitogenic stimulation but not following EBV infection.

B-Lymphocytes↗

Control of Anopheles stephensi breeding in construction sites and abandoned overhead tanks with Bacillus thuringiensis var. israelensis.

Bacillus thuringiensis (H-14), strain 164 (Bactoculicide) when applied at 1 g/m2 surface area successfully controlled Anopheles stephensi breeding in construction sites, abandoned overhead tanks, and curing waters. Subsequent to application, no pupal production was observed in these habitats for 3, 18, and 21 days, respectively. Based on these findings, inclusion of Bactoculicide in the bioenvironmental vector control strategy is suggested and fortnightly spraying in construction sites at 1 g/m2 surface area is recommended for the containment of vector breeding. However, frequent retreatment of abandoned overhead tanks would be uneconomical and operationally impractical.

Animals↗

Nosocomial outbreak of Salmonella typhimurium infection in a nursery intensive care unit (NICU) and paediatric ward.

A nosocomial outbreak of multidrug resistant Salmonella typhimurium in a Nursery Intensive Care Unit (NICU) and Paediatric ward is reported. Eight (16.6%) out of a total of 48 babies taken ill during this outbreak expired. Clinical manifestations included diarrhoea and fever. The organism was isolated from stool samples/rectal swabs of all the 48 cases and blood of 6 cases. An investigation was undertaken to trace the source of infection. The organism was isolated in pure cultures from three suction machines of NICU. The epidemic was immediately controlled with identification of the source but the question of how the suction machines were infected by this organism remained unsolved.

Child, Preschool↗

Synthesis and in vivo hypoglycemic screening studies on some life essential metal complexes of oral antidiabetic [N-(p-tolylsulphonyl)-N'-n butyl-urea] (tolbutamide).

Present communication deals with the synthesis of complexes of [N-(p-tolylsulphonyl)-N'-n butyl-urea], with certain transition metals viz. Cu(II), Zn(II), Fe(II) and Cd(II). Structures of all the complexes have been established on the basis of their consistent elemental and spectral analysis. Also, it reports their in vivo hypoglycemic screening on albino rats. Out of all the complexes studied, Zn-Tolbutamide complex could be recommended as more potent hypoglycemic agent in lieu of tolbutamide alone.

Administration, Oral↗

Role of imaging in temporal bone and cerebellopontine-angle lesions. A surgeon's perspective.

In recent years, with the advances in imaging technology, the gold standard for diagnosis of lesions of the temporal bone and cerebellopontine angle has shifted from histologic identification of the lesion from surgical specimens or autopsy material to noninvasive identification, localization, and characterization of the tissue by imaging. The symptoms caused by such lesions usually provide clues as to their location and probable nature. Clinical tests such as the vestibular evaluation, audiometry, auditory brain stem response, and otoacoustic emissions further help with topodiagnosis of the lesion. If this information is covered to the neuroradiologist, the most diagnostically productive imaging study can be obtained, and the neuroradiologist will apply the most appropriate technical parameters necessary for any individual patient. An eclectic algorithm can be applied for each clinical situation, and illustrative examples are provided in the article. The algorithms will no doubt change with advances in diagnostic tests. Application of imaging studies without adequate clinical investigations often makes the task of interpreting the scans difficult for the neuroradiologist. Furthermore, the positive diagnostic yield from a widespread use of imaging technology is small and would be considered an inappropriate use of health care dollars.

Adolescent↗

Effects of chronic fluoride toxicity on the morphology of ductus epididymis and the maturation of spermatozoa of rabbit.

This study used light and scanning electron microscopy to observe the effect of chronic fluoride toxicity on the structure of the ductus epididymis, testis and spermatozoa in rabbit. The rabbits were treated with 10 mg NaF/kg body weight/day for 20 and 23 months. Serum fluoride was estimated by the fluoride ion-specific electrode method. Fluoride levels in the sera of both 20 and 23-month treated rabbits were significantly increased (P < 0.001). Loss of stereocilia, significant decrease (P < 0.001) in the height of the pseudostratified columnar epithelium and significant increase (P < 0.001) in the diameter of both the caput and cauda ductus epididymis were observed only in the 23-month fluoride treated rabbits. The decreases in the epithelial cell height (P < 0.01) and the tubular diameter (P < 0.001) of the testis were significant only in 23-month treated animals. Spermatozoa in the lumen of the testis of both treated groups of animals and in the caput and cauda ductus epididymis of 20-month treated animals appeared normal, but spermatozoa in the caput and cauda ductus epididymis of 23-month treated animals were fragmented. In the 23-month fluoride treated rabbits, the weights of the caput and cauda epididymis were significantly reduced (P < 0.025) and there was also a reduction in the number of secretory granules in these organs. The structural changes observed in the caput and cauda ductus epididymis might adversely affect the maturation of spermatozoa.

Animals↗