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Das B, Arun VS, Seshadri M. Molecular genetic data at two tetranucleotide repeat loci (D12S66 and D12S67) in two Indian tribal populations. J Forensic Sci 2004; 49:854-5. [PMID: 15317214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Molecular genetic polymorphism study was undertaken in two tribal population groups of India at two tetranucleotide repeat loci on chromosome 12 (D12S66 and D12S67). The two tribal groups studied were Bison Horn Maria and Muria, belonging to Bastar district of Madhya Pradesh in Central India. For this study, 75 random, unrelated individuals were analyzed for D12S66 locus, whereas 76 individuals were analyzed for D12S67 locus.
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Das B, Seshadri M. Molecular genetic analysis of TPO and CD4 loci among two endogamous ethnic groups of Maharashtra in Western India. J Forensic Sci 2004; 49:861-2. [PMID: 15317218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Molecular genetic polymorphism study was undertaken in two endogamous ethnic groups of Maharashtra in Western India at two microsatellites i.e., TPO, a tetranucleotide repeat locus and CD4, a pentanucleotide repeat locus. The two ethnic groups studied were Konkanastha Brahmins and Marathas belonging to Indo-European language family. Eighty-two random, unrelated individuals were genotyped for the locus TPO, whereas for CD4 locus, 79 individuals were genotyped.
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Das B, Tandon V, Saha N. Anthelmintic efficacy of Flemingia vestita (Fabaceae): alteration in the activities of some glycolytic enzymes in the cestode, Raillietina echinobothrida. Parasitol Res 2004; 93:253-61. [PMID: 15138892 DOI: 10.1007/s00436-004-1122-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2004] [Accepted: 03/30/2004] [Indexed: 11/28/2022]
Abstract
The crude root-peel extract of Flemingia vestita, genistein and praziquantel were tested against some selected glycolytic enzymes--hexokinase (HK), phosphofructokinase (PFK), phosphoenolpyruvate carboxykinase (PEPCK), pyruvate kinase (PK), lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and malic enzyme (ME)--of the fowl tape worm, Raillietina echinobothrida. Following exposure to the various treatments, the activities of HK, PFK, PEPCK and LDH increased by 33-39%, 41-125%, 44-49% and 55-67%, respectively, and that of PK decreased by 14-26% in the parasite at the time of paralysis. The MDH and ME activities of the tissue homogenate were also found to be higher by 22-43% and 28-59%, respectively, in the treatments. However, whereas the activity of both cytosolic and mitochondrial MDH increased by 33-58% and 43-73%, respectively, the cytosolic ME activity showed an increase of 33-39%, and there was no significant enhancement in the mitochondrial ME activity. Histochemically, the enhancement in the activities of HK, LDH and MDH was clearly discernible. The enhanced glycolytic activity seems to be a function of anthelmintic stress caused by the phytochemicals.
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Chayani N, Das B, Sur M, Bajoria S. COMPARISON OF PARASITE LACTATE DEHYDROGENASE BASED IMMUNOCHROMATOGRAPHIC ANTIGEN DETECTION ASSAY (OPTIMAL) WITH MICROSCOPY FOR DETECTION OF MALARIA PARASITES. Indian J Med Microbiol 2004. [DOI: 10.1016/s0255-0857(21)02889-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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155
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Chayani N, Das B, Sur M, Bajoria S. Comparison of parasite lactate dehydrogenase based immunochromatographic antigen detection assay (optimal) with microscopy for detection of malaria parasites. Indian J Med Microbiol 2004; 22:104-6. [PMID: 17642705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
This study was done to compare the ability of a newly developed rapid malaria test OPtiMAL, an immunochromatographic antigen detection assay for the diagnosis of malaria using parasite lactate dehydrogenase, against standard microscopy. Blood samples were obtained from 232 patients suspected of having malaria. A total of 122 samples (52.5%) were positive by blood films while 118 (50.8%) were positive by OPtiMAL test. The blood film indicated that 21.4% (26 of 122) of the patients were positive for P. falciparum and 78.6% (96 of 122) were infected with P. vivax. OPtiMAL test showed that 21.2% (25 of 118) were positive for P. falciparum and 78.8% (93 of 118) were infected with P. vivax. This assay had sensitivities of 88.4% and 96.8% compared to traditional blood films for detection of P. falciparum and P. vivax malaria respectively. Thus OPtiMAL test can be used with or without traditional blood film examination for detection of both P. vivax and P. falciparum malaria and can be effectively used for the rapid diagnosis of malaria.
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Das B, Das P. Organochlorine pesticide residues in water, sediment, and muscle of river shad, Hilsa ilisha (Hamilton 1822) from the South Patches of the Bay of Bengal. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2004; 72:496-503. [PMID: 15114448 DOI: 10.1007/s00128-004-0293-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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Das B, Yeger H, Baruchel H, Freedman MH, Koren G, Baruchel S. In vitro cytoprotective activity of squalene on a bone marrow versus neuroblastoma model of cisplatin-induced toxicity. implications in cancer chemotherapy. Eur J Cancer 2004; 39:2556-65. [PMID: 14602142 DOI: 10.1016/j.ejca.2003.07.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The development of a non-toxic selective cytoprotective agent that preferentially protects normal tissues from chemotherapy toxicity, without protecting malignant tissues, is a major challenge in cancer chemotherapy research. The available cytoprotective agents are either toxic or lack selective cytoprotective activity. Here, we report the in vitro selective cytoprotective activity of squalene, an isoprenoid molecule with antioxidant properties. Normal human bone marrow (BM) derived colony-forming unit (CFU) growth was increased by squalene in a dose-dependent manner. Squalene (12.5-25 microM) treatment significantly protected the CFUs from cisplatin-induced toxicity; the protective effect was equivalent to reduced glutathione (GSH), a known cytoprotective agent. Squalene also increased the long-term survival of cisplatin-treated 4-week-old CFUs. Cisplatin-induced apoptosis of CFUs as measured by the TUNEL assay was reduced by squalene. To examine the squalene-induced protection of tumours, several neuroblastoma cell lines, including five MYCN-amplified cell lines, were grown in monolayers, as well as in anchorage-independent cultures, in the presence of squalene and cisplatin. Squalene did not protect the neuroblastoma (NBL) cell lines from cisplatin-induced toxicity. In addition, squalene did not protect the NBL cells from carboplatin, cyclophosphamide, etoposide and doxorubicin-induced toxicity. In conclusion, our results suggest that squalene has a selective in vitro cytoprotective effect on BM-derived haematopoietic stem cells that is equipotent to GSH.
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Das B, Banerjee S. Inertial snake for contour detection in ultrasonography images. ACTA ACUST UNITED AC 2004. [DOI: 10.1049/ip-vis:20040310] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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159
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Das B, Seshadri M. Polymorphism data at DYS385 locus in five ethnic groups from Kerala in Southern West India. J Forensic Sci 2004; 49:181-2. [PMID: 14979372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
POPULATION We have studied the DNA polymorphism at DYS385, a Y-chromosomal tetranucleotide repeat locus among five anthropologically distinct ethnic groups of Kerala state in Southern West India. The ethnic groups were Ezhavas, Muslims, Nairs, Arayas and Thandans and they speak "Malayalam." an Indo-Dravidian language. Peripheral blood samples were collected from 72 random, healthy and normal male volunteers for this study.
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Shankar PR, Das B, Partha P, Shenoy N, Dubey AK. Inter-rater reliability of the assessment of communication skills in Pharmacology. JNMA J Nepal Med Assoc 2003. [DOI: 10.31729/jnma.619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Effective communication skills are required for medical students and doctors. Communication skills trainingand assessment in Pharmacology is conducted in English using simulated patients. The assessment procedurehas not been tested for inter-rater reliability. To overcome this deficiency, the present study was carried outto obtain information on the agreement between two independent observers simultaneously evaluating thestudents using a standardized check list. The study was conducted on 175 second and fourth semestermedical students at the Manipal College of Medical Sciences, Pokhara, during the month of December2001. Two observers, who had agreed beforehand on the scoring criteria and the checklist to be used,simultaneously and independently evaluated the students. Kappa test was used to measure agreement. Therewas very good to moderate agreement regarding the total scores. Very good to moderate agreement was alsoseen for the parameters: drug-related factors and non-drug factors. Individual factors showed poor agreementbecause of the ‘kappa paradox’. The findings, overall, demonstrate the validity of the system of assessment.This was a preliminary study and more detailed studies are required before modifications in the system ofcommunication skills assessment can be suggested.Key Words: Communication, Educational measurement, Undergraduate medical education.
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Das B, Phil M, Seshadri M. DNA polymorphism study at D1S80, DYS19, DYS287, and DYF155S2 in two tribal populations from Central India. J Forensic Sci 2003; 48:1193-4. [PMID: 14535698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
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162
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Das B, Phil M, Seshadri M. Haplotype frequency distribution of two autosomal microsatellites (D12S66 and D12S67) among five endogamous population groups in India. J Forensic Sci 2003; 48:1191-2. [PMID: 14535697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
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163
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Das B, Meirovitch H, Navon IM. Performance of hybrid methods for large-scale unconstrained optimization as applied to models of proteins. J Comput Chem 2003; 24:1222-31. [PMID: 12820130 DOI: 10.1002/jcc.10275] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Energy minimization plays an important role in structure determination and analysis of proteins, peptides, and other organic molecules; therefore, development of efficient minimization algorithms is important. Recently, Morales and Nocedal developed hybrid methods for large-scale unconstrained optimization that interlace iterations of the limited-memory BFGS method (L-BFGS) and the Hessian-free Newton method (Computat Opt Appl 2002, 21, 143-154). We test the performance of this approach as compared to those of the L-BFGS algorithm of Liu and Nocedal and the truncated Newton (TN) with automatic preconditioner of Nash, as applied to the protein bovine pancreatic trypsin inhibitor (BPTI) and a loop of the protein ribonuclease A. These systems are described by the all-atom AMBER force field with a dielectric constant epsilon = 1 and a distance-dependent dielectric function epsilon = 2r, where r is the distance between two atoms. It is shown that for the optimal parameters the hybrid approach is typically two times more efficient in terms of CPU time and function/gradient calculations than the two other methods. The advantage of the hybrid approach increases as the electrostatic interactions become stronger, that is, in going from epsilon = 2r to epsilon = 1, which leads to a more rugged and probably more nonlinear potential energy surface. However, no general rule that defines the optimal parameters has been found and their determination requires a relatively large number of trial-and-error calculations for each problem.
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Das B, Kar S, Sanyal D, Banerjee D, Bhattacharya R. Study of polyaniline polyacrylamide composites by positron annihilation technique. J Appl Polym Sci 2003. [DOI: 10.1002/app.12071] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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165
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Gomes A, Das M, Sur P, Besra SE, Chakravorty AK, Das B, Ganguly DK, Vedasiromoni JR. Glycosmis arborea extract as a hepatoprotective agent. Phytother Res 2003; 17:571-4. [PMID: 12749004 DOI: 10.1002/ptr.1191] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Glycosmis arborea is a plant possessing various medicinal properties. The aim of the present study was to investigate the hepatoprotective efficacy of the butanol extract obtained from the aerial parts of the plant. The test sample was prepared by extracting the material through different steps. The extract thus obtained was dissolved in normal saline. Albino rats were prophylactically treated with the extract (i.p.) for 3 weeks. At the end of 3rd week all the groups were injected with hepatotoxic agents. After 48 h of injection, blood was collected and livers were taken out. Different enzymes in the serum were assayed and histopathological study was performed with liver. Glycosmis arborea extract was able to overcome the toxic effects of hepatotoxic agents in terms of lowering the levels of serum GPT, alkaline phosphatase and increased level of SOD in serum. TBARS generation in liver was also altered. Moreover, necrosis of liver produced by carbon tetrachloride was reversed by the extract.
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Ghosh A, Das B, Seshadri M. Population genetic analysis among five Indian population groups using six microsatellite markers. Hum Biol 2003; 75:189-203. [PMID: 12943158 DOI: 10.1353/hub.2003.0032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Genetic variation at six tetranucleotide microsatellites (HUMTHO1, HUMVWA, F13A01, D3S1359, D12S66, and D12S67) has heen determined in five endogamous ethnic population groups of India belonging to two major linguistic families. The populations analyzed were Konkanastha Brahmins and Marathas (Maharashtra state) from the Indo-Aryan linguistic family and Nairs, Ezhavas, and Muslims (Kerala state) from the Dravidian family. All six loci show high gene diversity, ranging from 0.63 +/- 0.04 to 0.84 +/- 0.02. The average GST value observed was 1.7%, indicating that the differences between the populations account for less than 2% of the diversity, while the genetic variation is high within the five population groups studied (>98%). The phylogenetic tree fails to show any clear cluster. The absence of any cluster along with low average GST is suggestive of substantial genetic similarity among the studied populations, in spite of clear geographical, linguistic, and cultural barriers. This similarity indicates either a greater gene flow between these groups or, alternatively, may reflect a recent evolution for them, considering that the Indian caste system evolved only about 3000 years ago.
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Das B, Sarkar C. Selective mitochondrial KATP channel activation by nicorandil and 3-pyridyl pinacidil results in antiarrhythmic effect in an anesthetized rabbit model of myocardial ischemia/reperfusion. METHODS AND FINDINGS IN EXPERIMENTAL AND CLINICAL PHARMACOLOGY 2003; 25:97-110. [PMID: 12731455 DOI: 10.1358/mf.2003.25.2.723683] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The roles of cardiomyocyte sarcolemmal ATP-sensitive K+ (KATP) and mitochondrial KATP channels in cardioprotection and antiarrhythmic activity induced by KATP channel openers remain obscure. However, it has been suggested that the mitochondrial KATP channels are involved as a subcellular mediator in cardioprotection afforded by ischemic preconditioning. In the present study, we investigated the effects of the administration of non-hypotensive doses of ATP-sensitive K+ channel (KATP) openers (nicorandil and 3-pyridyl pinacidil), a specific mitochondrial KATP channel blocker (5-hydroxydecanoate) and a specific sarcolemmal KATP channel blocker (HMR 1883; 1-[5-[2-(5-chloro-o-anisamido)ethyl]-2-methoxyphenyl]sulfonyl-3- methylthiourea) prior to and during coronary occlusion, as well as prior to and during post-ischemic reperfusion, on survival rate, ischemia-induced and reperfusion-induced arrhythmias and myocardial infarct size in anesthetized albino rabbits. The thorax was opened in the left 4th intercostal space and after pericardiotomy the heart was exposed. In Group I (n = 80), occlusion of the left main coronary artery and hence, myocardial ischemia-induced arrhythmias were achieved by tightening a previously placed loose silk ligature for 30 min. In Group II (n = 186), arrhythmias were induced by reperfusion following a 20 min ligation of the left main coronary artery. In both Group I and Group II, early intravenous infusion of nicorandil (100 micrograms/kg bolus + 10 micrograms/kg/min), 3-pyridyl pinacidil (3.0 micrograms/kg bolus + 1.0 microgram/kg/min), HMR 1883 (3 mg/kg)/nicorandil and HMR 1883 (3 mg/kg)/3-pyridyl pinacidil, just prior to and during ischemia, increased survival rate (75%, 67%, 86% and 75% vs. 60% in the control subgroup in Group I; 67%, 75%, 75% and 67% vs. 43% in the control subgroup in Group II), significantly decreased the incidence and severity of life-threatening arrhythmias and significantly decreased myocardial infarct size. However, late intravenous administration of nicorandil or 3-pyridyl pinacidil at the onset of and during reperfusion did not increase survival rate nor confer any antiarrhythmic or cardioprotective effects. The antiarrhythmic and cardioprotective effects of both nicorandil and 3-pyridyl pinacidil were abolished by pretreating the rabbits with 5-hydroxydecanoate (5 mg/kg, i.v. bolus), a selective mitochondrial KATP channel blocker, but not by pretreatment with HMR 1883 (3 mg/kg). In the present study, higher levels of malondialdehyde (MDA) and lower levels of reduced glutathione (GSH) and superoxide dismutase (SOD) in the necrotic zone of myocardium in all sixteen subgroups in Group II suggest little anti-free radical property of nicorandil and 3-pyridyl pinacidil. Therefore, we may conclude that intervention by intravenous administration of nicorandil and 3-pyridyl pinacidil (through the selective activation of mitochondrial KATP channels), increases survival rate and exhibits antiarrhythmic and cardioprotective effects during coronary occlusion and reperfusion in anesthetized rabbits, when administered prior to and during coronary occlusion. The mitochondrial KATP channel may be considered to be a potentially important site of cardioprotection and antiarrhythmic activity.
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Rastogi S, Das B, Salhan S, Mittal A. Effect of treatment for Chlamydia trachomatis during pregnancy. Int J Gynaecol Obstet 2003; 80:129-37. [PMID: 12566185 DOI: 10.1016/s0020-7292(02)00371-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To screen and treat chlamydial infection in pregnant women in order to assess the effects of therapeutic intervention on the outcome of Chlamydia trachomatis-infected pregnancy. METHODS Enrolled in the study were 350 women in the first to third trimesters of pregnancy. Endocervical swabs were collected for C. trachomatis diagnosis by DFA and PCR. A few STD infections, viz.: Neisseria gonorrhoeae, Candida spp., bacterial vaginosis, Trichomonas vaginalis and Treponema pallidum were ruled out. After excluding 22 patients infected with other sexually transmitted infections, a cohort of 328 pregnant women comprised the study population. Anti-chlamydial treatment (viz.: oral therapy with erythromycin stearate, 500 mg 4 times daily for 7 days) was given to 17 women (group I) and their partners. Fifteen patients of group I were retested by DFA and PCR assay for C. trachomatis infection 2 weeks following therapy. Other Chlamydia-positive patients (n=42) who were lost to follow-up were classified as untreated positive cases (group II) while group III included C. trachomatis negative cases (n=269). Data on obstetric outcome were recorded in a total of 164 cases. Statistical comparison of the data were done using the chi(2)-test and means were compared using Student's t-test. RESULTS Among the 350 pregnant women enrolled initially for the study, C. trachomatis positivity was found to be 18.8% (n=66) in the endocervix by DFA and PCR assay. Co-infection with Candida spp., bacterial vaginosis, T. vaginalis and T. pallidum was 2.0%, 1.7%, 1.7% and 0.5%, respectively. None of the pregnant women was infected with N. gonorrhoeae. Pregnant women at an increased risk of chlamydial infection included those who had multiple births and were in second trimester of pregnancy. Fifteen patients of group I became Chlamydia-negative following treatment. Data on obstetric outcome were recorded in 11, 26 and 127 patients of groups I, II and III, respectively. The mean duration of gestation for premature deliveries was found to be significantly higher in group I in comparison with group II [35.5 vs. 33.1 weeks (P<0.05)], thereby showing an improved effect of treatment on pregnancy outcome. The mean of low birth weight births was higher in group I compared with group II (2200.0 vs. 2113.3 g), however, this was statistically non-significant. Stillbirths were significantly higher among group II in comparison with group III [11.5% vs. 4.7% (chi(2)=1.79; P<0.5)]. No stillbirths were recorded in patients who had taken anti-chlamydial treatment. CONCLUSIONS Our findings suggest that routine screening and treatment of C. trachomatis infection in pregnant women, especially those in high risk groups, should be mandatory to reduce the adverse effects on obstetric outcome.
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Singh O, Das B, Padhi M, Tewari N. Common herbs used in different skin disorders as described in ayurvedic classics. Anc Sci Life 2003; 22:88-94. [PMID: 22557091 PMCID: PMC3331009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2002] [Accepted: 12/30/2002] [Indexed: 11/05/2022] Open
Abstract
Diseases of skin account for a great deal of misery, suffering, incapacity and economic loss, Including the genetic causes the diet, climate, sunlight mental factors and allergy etc. have been proved as aetiological factors beyond doubts. Natural herbs seem to be more promising in the field of dematology as already described in ancient Ayurvedic texts.
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Das B, Padhi M, Singh O, Deep V, Tewari N, Panda N. Clinical evaluation of nirgundi taila in the management of sandhivata. Anc Sci Life 2003; 23:22-34. [PMID: 22557109 PMCID: PMC3330953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2002] [Accepted: 04/10/2003] [Indexed: 10/26/2022] Open
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171
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Sarkar C, Das B, Sripathi H. DRUG PRESCRIBING PATTERN IN DERMATOLOGY IN A TEACHING HOSPITAL IN WESTERN NEPAL. JNMA J Nepal Med Assoc 2003. [DOI: 10.31729/jnma.732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The aim was to monitor drug prescribing for patients attending the dermatologyservices (OPD) of Manipal Teaching Hospital (MTH). 292 prescriptions of patientsattending the dermatology OPD of MTH attached to MCOMS, Nepal were collectedby a random once weekly survey between July 2000 to June 2001. This informationwas analysed in consultation with clinical collaborators and critically evaluated usingWHO guidelines. The average number of drugs prescribed was 2.42 drugs/prescription.Only 13%(91 out of 708) of the drugs were prescribed in generic names. The mostcommonly prescribed topical drugs were topical steroids and their combinations (28%)followed by topical antifungal agents (12.5%). The most commonly prescribed systemicagents were antihistamines (47.6%) followed by antimicrobials (20%) and antifungalagents (12%). Frequency of administration and site of application were specified inthe majority of the prescriptions (82%) of topically administered drugs but dose/strength of topical preparations were specified in only 11 prescriptions. The durationwas not specified for 9 of the systemically prescribed drugs and 341 of all the topicaldrugs prescribed. In two patients, 2 medium or 2 high potency topical steroids wereprescribed together with systemic steroid administration. Patients who receivedsystemic antiiungal agents (34) also got a topical one simultaneously. In this study, agreat majority of the drugs were prescribed in brand names (87 %). Drugs should beprescribed in their generic names to * avoid confusion and to minimize the costs. Inthis study, on some occasions, prescriptions may have been written imprecisely/inappropriately.Key Words: Prescribing pattern, Dermatology, Nepal.
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Das B, Chauhan PS, Seshadri M. Genetic variation observed at two tetrameric short tandem repeat loci on chromosome 12 (D12S66 and D12S67) among five distinct ethnic groups of India: detection of two new alleles. Ann Hum Biol 2002; 29:513-25. [PMID: 12396371 DOI: 10.1080/03014460110119766] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The present investigation reports the genetic variation observed at two tetrameric short tandem repeat (STR) loci on chromosome 12 (D12S66 and D12S67) among five anthropologically distinct population groups of India. SUBJECTS AND METHODS A total of 277 random, normal and healthy volunteers were investigated for the D12S66 locus, and 236 for the locus D12S67, from five ethnic groups of India. Two of these belong to the state of Maharashtra in western India (Konkanastha Brahmins and Marathas) and three from the state of Kerala in South India (Nairs, Ezhavas and Muslims). DNA was extracted from peripheral blood samples, amplified by duplex polymerase chain reaction (PCR) and electrophoresed on 6% denaturing urea (7 M) gel electrophoresis. The analysis was performed on ALF Express DNA sequencer (Amersham Pharmacia Biotech) using Fragment Manager software. Statistical analysis was done by using Arlequin ver. 1.1. RESULTS At D12S66 locus, a total of nine alleles (8-17 repeats) and 27 genotypes were detected with an observed heterozygosity ranging from 0.55 to 0.91. At the D12S67 locus, nine alleles (36-44 repeats) and 33 genotypes were observed with a heterozygosity ranging from 0.74 to 0.89. Both the loci displayed high Power of Discrimination (PD) which ranged from 0.81 to 0.91 and Polymorphic Information Content (PIC) ranging from 0.68 to 0.84. At D12S66, two alleles were detected for the first time in these population groups which were not reported earlier. The level of gene differentiation (G(ST) value, 0.02) was moderate at these two loci, indicating a close relationship among the population groups. CONCLUSIONS From this investigation, it is concluded that both the tetrameric loci are highly polymorphic and informative, and can be used for the characterization of the Indian population groups in addition to other well-studied STR loci.
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Mathur P, Kapil A, Das B, Dhawan B, Dwivedi SN. Invasive beta-haemolytic streptococcal infections in a tertiary care hospital in northern India. J Med Microbiol 2002; 51:791-792. [PMID: 12358071 DOI: 10.1099/0022-1317-51-9-791] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Das B, Ghosh A, Chauhan PS, Seshadri M. Genetic polymorphism study at four minisatellite loci (D1S80, D17S5, D19S20, and APOB) among five Indian population groups. Hum Biol 2002; 74:345-61. [PMID: 12180760 DOI: 10.1353/hub.2002.0028] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The present study reports the genetic variation observed among five anthropologically distinct population groups of India, using four highly polymorphic minisatellite loci (D1S80, D17S5, D19S20, and APOB 3' VNTR) in order to examine the effect of geographical and linguistic affiliations on the genetic affinities among these groups. Random individuals from five ethnic groups were studied; the sample size ranged from 235 to 364. The population groups belong to two geographically separated regions of India, the state of Maharashtra (western India) and the state of Kerala (southern India). The two Maharashtrian groups (Konkanastha Brahmins and Marathas) speak "Marathi," an Indo-European language, whereas the three Kerala population groups (Nairs, Ezhavas, and Muslims) speak "Malayalam," an Indo-Dravidian language. Genomic DNA was extracted from peripheral blood samples and analyzed using amplified fragment length polymorphism (Amp-FLP) technique. All four loci displayed high heterozygosity with average heterozygosity in the range of 0.82 to 0.84. The Polymorphic Information Content and Power of Discrimination were > or = 0.75 and > or = 0.80, respectively. The coefficient of gene differentiation was found to be low (average G(ST) = 1.2%; range between 0.6% at D1S80 locus to 1.6% at APOB 3' VNTR locus) across the loci, indicating close affinity among the population groups. The neighbor-joining tree revealed two clear clusters, one for the two Maharashtrian population groups and the other for the three Kerala population groups. The results obtained are in conformity with the geographical and linguistic backgrounds of the studied populations.
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Das B, Chauhan PS, Seshadri M. Y-chromosomal STR haplotypes in two population groups of Kerala in south India. J Forensic Sci 2002; 47:690-1. [PMID: 12051368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
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176
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Sarkar C, Das B, Sripathi H. Antimicrobial drug use in dermatology in a teaching hospital in western Nepal. Int J Clin Pract 2002; 56:258-60. [PMID: 12074207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
Medical audit is supposed to oversee, monitor and analyse standards of medical treatment at all levels of the healthcare delivery system. This study was undertaken to monitor the prescribing of antimicrobial drugs for patients seeking treatment in the dermatology outpatient department of the Manipal Teaching Hospital in Nepal. A total of 292 dermatology prescriptions of patients attending the dermatology OPD were collected between July 2000 and June 2001. Prescriptions for antimicrobial agents were separated from the total prescriptions collected, and evaluated. There were more female patients (58.2%) than male (41.8%) in our study; most were in the 21-40 year age group. The commonest cutaneous infections were acne (15.8%) followed by fungal infections (14.8%). Of the 292 prescriptions audited, 149 contained antimicrobial agents, constituting 36% of the total number of drugs prescribed. Of 256 antimicrobials prescribed, 63% were topical and 37% systemic; 5% were generic, 29% were from the essential drug list of Nepal, and 15% were fixed-dose combinations. Most of the patients received one or two antimicrobials, 50% of which were antibacterials and 40% antifungals. Though the selection of antimicrobial drugs used in dermatology was largely rational, anomalies were observed, and these issues were discussed with clinicians in relation to various aspects of drug use. The results indicate there is scope for improving prescribing habits. A periodic audit of drug prescribing is desirable in rationalising prescribing practice.
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Shome SC, Das HR, Das B. Spectrophotometric Determination of Thallium(III) with 3-Hydroxy-1,3-Diphenyltriazine in 70% Alcohol. Anal Chem 2002. [DOI: 10.1021/ac60243a016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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178
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Das B, Carlin R, Osteryoung RA. The ferro/ferricyanide couple in an aluminum chloride-1-methyl-3-ethylimidazolium chloride ambient-temperature molten salt. Inorg Chem 2002. [DOI: 10.1021/ic00302a011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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179
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Das B, Chauhan PS, Seshadri M. Population database of Y-chromosomal haplotypes at five microsatellites among two distinct ethnic groups of western India. J Forensic Sci 2002; 47:692-3. [PMID: 12051369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
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180
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Nádasi H, Weissflog W, Eremin A, Pelzl G, Diele S, Das B, Grande S. Ferroelectric and antiferroelectric “banana phases” of new fluorinated five-ring bent-core mesogens. ACTA ACUST UNITED AC 2002. [DOI: 10.1039/b111421b] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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181
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Das B, Chauhan PS, Seshadri M. Allele frequency distribution at five Y-chromosomal short tandem repeat loci among five distinct ethnic groups of India. J Forensic Sci 2002; 47:410-2. [PMID: 11908623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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182
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Das B, Sarkar C, Karanth KS. Effects of nicorandil administration on survival rate and arrhythmias during reperfusion in anesthetized rabbits. Pharmacology 2002; 63:134-41. [PMID: 11598418 DOI: 10.1159/000056124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The aim was to study the effects of nicorandil (an ATP-sensitive K+ channel opener) and tolbutamide (an ATP-sensitive K+ channel blocker) on reperfusion-induced arrhythmias in pentobarbitone and ketamine anesthetized rabbits. Arrhythmias were induced by reperfusion for 20 min following a 15-min ligation of the left main coronary artery with a silk ligature. Rabbits were pretreated with nicorandil (0.47, 0.93 or 1.86 mg/kg i.v.) or tolbutamide (180 mg/kg i.p.) or vehicle (dimethylsulfoxide/saline) before the coronary artery occlusion. In the control group (n = 10), only 60% of the animals survived during reperfusion. Intravenous pretreatment with 0.47, 0.93 or 1.86 mg/kg of nicorandil increased the survival rate to 86% (n = 7), 75% (n = 8) and 86% (n = 7), respectively. Nicorandil pretreatment significantly decreased the incidence and duration of reperfusion-induced life-threatening arrhythmias and increased the number of animals that survived without developing any arrhythmia. Tolbutamide pretreatment was associated with a decreased survival rate of 50% (n = 12) and an increase in the incidence and duration of reperfusion-induced arrhythmias. Pretreatment with nicorandil may result in protection against reperfusion-induced arrhythmias and increased survival in anesthetized rabbits.
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183
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Singh OP, Das B, Padhi MM, Tewari NS. Kushtha (skin disorders) in vedic and other religious literatures - A review. BULLETIN OF THE INDIAN INSTITUTE OF HISTORY OF MEDICINE (HYDERABAD) 2002; 32:51-5. [PMID: 15307215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
In view of the description of Medical citations; Vedic literature, Buddhist literature, Jain literature, Mahabharat, Ramayan etc. have also got significant importance. Like other diseases, the description regarding Kushtha (different skin disorders) is also available in all these treatises. These are akin to the description available in Ayurveda. From the above, it is apparent that description of different diseases mentioned in Ayurveda are also available in religious literatures.
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Sing OP, Deep V, Das B, Padhi M, Tewari N. Liver and skin disorders - a scientific review. Anc Sci Life 2002; 22:9-11. [PMID: 22557080 PMCID: PMC3330996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2002] [Accepted: 06/16/2002] [Indexed: 11/10/2022] Open
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Das B, Tao SZ, Mushnitsky R, Norin AJ. Genetic identity and differential expression of p38.5 (Haymaker) in human malignant and nonmalignant cells. Int J Cancer 2001; 94:800-6. [PMID: 11745481 DOI: 10.1002/ijc.1555] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Previous studies from our laboratory revealed a novel protein of 38.5 kD on the surface of malignant cell lines of hematopoetic origin that exhibit susceptibility to naive natural killer (NK) cell-mediated lysis. In contrast, p38.5 was not detected on the surface of NK cell-resistant carcinoma cell lines or normal cells. We now report that this protein is differentially expressed, intracellularly, in malignant cell lines of both hematopoetic and epithelial origin compared with nonmalignant cells. To characterize p38.5 further, we used a previously developed antipeptide antibody (anti-11-mer) to probe cDNA expression libraries and subsequently performed 5' extension by rapid amplification of cDNA ends (RACE). Sequence analyses of these cDNA clones reveal open reading frames (ORFs) that include the previously identified 11-mer peptide from purified, native p38.5 and that have identical sequences to a gene of unknown function on chromosome 19. Nucleotide sequence data obtained from these cDNA clones, as well as analysis of the genomic sequence, permitted design of primers for reverse transcriptase-polymerase chain reaction (RT-PCR) that resulted in a cDNA clone encoding an ORF of 361 amino acids; the clone was identical to a sequence encoded by an unpublished mRNA in GenBank. Anti-p38.5 antibody against the 11-mer peptide encoded in exon 5 and against a 25-mer peptide encoded in exon 1 both reacted with the same protein in immunoprecipitation studies, providing further evidence of identity. RT-PCR and Northern blot analyses both demonstrated p38.5 gene transcripts in normal cells, nonmalignant cell lines and malignant cell lines of epithelial as well as hematopoietic origin. Semiquantitative studies revealed a greater level of p38.5 gene transcription in malignant cell lines compared with nonmalignant cells. Immunoblot analyses of protein expression confirmed and extended the latter studies by revealing substantially greater levels of the 38.5 kD protein in whole cell extracts of malignant cell lines compared with nonmalignant cells. Quantitative differences in detection of the 38.5 kD protein and mRNA in NK susceptible- hematopoietic malignancies compared with NK resistant-carcinomas were not observed. These experiments suggest that the p38.5 gene (Haymaker) is widely expressed in human cells of different tissue origins but that elevated expression is associated with the malignant phenotype.
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186
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Das B, Saha SP. Trigeminal neuralgia: current concepts and management. JOURNAL OF THE INDIAN MEDICAL ASSOCIATION 2001; 99:704-9. [PMID: 12022221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Trigeminal neuralgia is the most frequent cranial neuralgia, the incidence being 1 per 1,000,00 persons per year. It presents with stabbing pain often in the distribution of the mandibular and maxillary divisions of the trigeminal nerve. An accurate history of pain is important in the diagnosis of trigeminal neuralgia. A patient with tic douloureux and no neurological abnormality on clinical examination does not need diagnostic tests. The available options for management of trigeminal neuralgia are: Pharmacotherapy, destructive procedures and non-destructive procedures. The pharmacotherapy includes (i) monotherapy with one anticonvulsant, (ii) combined therapy with more than one anticonvulsant, (iii) add-on therapy with newer drugs and (iv) polytherapy with anticonvulsant + add-on drugs + antidepressants/anxiolytics. Destructive procedures include (i) non-surgical methods--injections along trigeminal pathways, percutaneous trigeminal radiofrequency thermocoagulation and (ii) surgical methods--trigeminal branch avulsion or peripheral neurectomy, avulsion of trigeminal nerve, trigeminal tractotomy, radiosurgery. Though various modalities of treatment are available for the management of trigeminal neuralgia, pharmacotherapy with carbamazepine still remains the first line of treatment. The alternative approach followed at most centres is percuatenous Gasserian rhizolysis (chemical/radiofrequency thermal) or microvascular decompression.
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Mandal P, Kapil A, Goswami K, Das B, Dwivedi SN. Uropathogenic Escherichia coli causing urinary tract infections. Indian J Med Res 2001; 114:207-11. [PMID: 12040764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
BACKGROUND & OBJECTIVES The information on the characteristics of Escherichia coli causing urinary tract infections is limited. We have characterised the urovirulence factors of Esch. coli isolated from symptomatic patients of urinary tract infections (UTI) in order to determine their pathogenic potential and the antibiotic sensitivity profile. METHODS Semi-quantitative urine culture was done on 370 symptomatic patients suffering from urinary tract infections. Phenotypic characterization of the urovirulence factors of Esch. coli was undertaken and the antibiotic susceptibility was determined. RESULTS Esch. coli was responsible for 45.5 per cent of infections. Resistance to amoxycillin, cotrimoxazole, nalidixic acid, norfloxacin and ciprofloxacin among Esch. coli isolates ranged from 70-95 per cent. Serotype O101 was found to be the commonest serotype (7/26). The virulence factors associated with uropathogenic Esch. coli were haemolysin production (5/30), presence of mannose resistant P-fimbriae (5/30), presence of mannose sensitive type 1 fimbriae (6/30) and the presence of mannose resistant F-fimbriae (2/30). Siderophores production was seen in all the isolates causing UTI. INTERPRETATION & CONCLUSION Esch. coli was found to be the commonest cause of UTI in our study population. Antibiotic resistance was high among the strains circulating which emphasises the need for judicious use of antibiotics. Certain virulence factors like haemolysin production and presence of fimbriae in the Esch. coli may be associated with the urovirulence.
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Das B, Ghosh A, Chauhan PS, Seshadri M. Population data of two minisatellite loci (D1S80 and D17S5) among five distinct ethnic groups of India. J Forensic Sci 2001; 46:1518-9. [PMID: 11714173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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189
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Das B, Sarkar C, Karanth KS. Effects of administration of nicorandil or bimakalim prior to and during ischemia or reperfusion on survival rate, ischemia/reperfusion-induced arrhythmias and infarct size in anesthetized rabbits. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2001; 364:383-96. [PMID: 11692221 DOI: 10.1007/s002100100457] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2000] [Accepted: 05/28/2001] [Indexed: 11/24/2022]
Abstract
We investigated the effects of administration of non-hypotensive doses of ATP-sensitive K+ channel (KATP) openers (nicorandil and bimakalim), and a specific mitochondrial KATP channel blocker (5-hydroxydecanoate) prior to and during coronary occlusion as well as prior to and during post-ischemic reperfusion on survival rate, ischemia-induced and reperfusion-induced arrhythmias and myocardial infarct size in anesthetized albino rabbits. The thorax was opened in the left fourth intercostal space and after pericardiotomy the heart was exposed. In Part I, occlusion of the left main coronary artery and hence, myocardial ischemia-induced arrhythmias were achieved by tightening a previously placed loose silk ligature for 30 min. In Part II, arrhythmias were induced by reperfusion following a 20-min ligation of the left main coronary artery. In Part I, early intravenous infusion of nicorandil (100 microg/kg bolus + 10 microg/kg per min) or bimakalim (3 microg/kg bolus + 0.1 microg/kg per min) just prior to and during ischemia increased survival rate (75% and 67% vs. 60% in the control group), significantly decreased the incidence and severity of life-threatening arrhythmias and significantly decreased myocardial infarct size. In Part II also, early intervention by intravenous infusion of nicorandil (100 microg/kg bolus + 10 microg/kg per min) or bimakalim (3 microg/kg bolus + 0.1 microg/kg per min) just before and during ischemia increased survival rate (86% and 75% vs. 55% in the control group), significantly decreased the incidence and severity of life-threatening arrhythmias and significantly decreased myocardial infarct size. However, late intravenous administration of nicorandil or bimakalim at the onset and during reperfusion did not increase survival rate nor confer any antiarrhythmic or cardioprotective effects. The antiarrhythmic and cardioprotective effects of both nicorandil and bimakalim were abolished by pretreating the rabbits with 5-hydroxydecanoate (5 mg/kg, i.v. bolus), a selective mitochondrial KATP channel blocker. In conclusion, intervention by intravenous administration of nicorandil and bimakalim (through the activation of mitochondrial KATP channels), increased survival rate and exhibited antiarrhythmic and cardioprotective effects during coronary occlusion and reperfusion in anesthetized rabbits when administered prior to and during coronary occlusion.
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Myers MR, Das B. Virus transmission through compromised synthetic barriers: part I--effect of unsteady driving pressures. J Biomech Eng 2001; 123:506-12. [PMID: 11601737 DOI: 10.1115/1.1394198] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Although synthetic membranes such as gloves, condoms, and instrument sheaths are used in environments with highly time-varying stresses, their effectiveness as barriers to virus transmission is almost always tested under static conditions. In this paper it is shown how a previously developed mathematical model can be used to transform information from static barrier tests into predictions for more realistic use conditions. Using a rate constant measured for herpes adsorption to latex in saline, and an oscillatory trans-membrane pressure representative of coitus, the amount of virus transmitted through a hole (2 microm diameter) in a condom is computed. Just beyond the exit orifice of the pore, transport is dominated by the rapidly dissipating viscous jet of virus suspension, which results in an accumulation of viruses roughly 20 pore radii from the barrier surface during each cycle. Due to virus adsorption to the barrier surfaces, the simulations reveal a gradual decrease in virus flow with increasing number of cycles, and thus a slow divergence from predictions based upon steady-state conditions. Still, over the 500 cycles simulated, steady-state predictions approximate the net number of viruses transmitted to within 25 percent error.
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191
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Das B, Myers MR. Virus transmission through compromised synthetic barriers: part II--influence of pore geometry. J Biomech Eng 2001; 123:513-8. [PMID: 11601738 DOI: 10.1115/1.1394199] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
When stressed during normal use, synthetic barriers such as gloves and condoms can develop tears that are undetectable by the user. It is of considerable public-health importance to estimate the quantity of virus transmitted through the tear, in the event of viral contamination of the fluid medium. A mathematical model that accounts for virus adsorption to the barrier material was used to compute the quantity of virus transmitted through defects of various geometries. Slits were modeled as cylinders of elliptic cross section, and upper and lower bounds for the transmission rate of HIV and Hepatitis B virus (HBV) were calculated for barrier-use scenarios such as coitus and gripping of surgical instruments. For a 1-microm high slit, HIV transmission was found to be negligible for all likely use scenarios. HIV transmission became potentially significant for a 5-microm slit. Due to its high titer, HBV transmitted at potentially important levels even through the 1-microm slit. The dependence of the transmission rate upon pore aspect ratio was determined and found to be very strong for high-adsorption situations and near-circular pores. Numerical predictions of virus transport through a laser-drilled hole in a condom matched experimental measurements well, even when the tapered nature of the geometry is ignored.
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Schreiber AM, Das B, Huang H, Marsh-Armstrong N, Brown DD. Diverse developmental programs of Xenopus laevis metamorphosis are inhibited by a dominant negative thyroid hormone receptor. Proc Natl Acad Sci U S A 2001; 98:10739-44. [PMID: 11517345 PMCID: PMC58545 DOI: 10.1073/pnas.191361698] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/16/2001] [Indexed: 11/18/2022] Open
Abstract
Metamorphosis of anuran tadpoles is controlled by thyroid hormone (TH). Here we demonstrate that transgenic Xenopus laevis tadpoles expressing a dominant negative form of TH receptor-alpha are resistant to a wide variety of the metamorphic changes induced by TH. This result confirms that TH receptors mediate both early and late developmental programs of metamorphosis as diverse as growth in the brain, limb buds, nose and Meckel's cartilage, remodeling of the intestine, and death and resorption of the gills and tail.
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Gulati S, Kapil A, Das B, Dwivedi SN, Mahapatra AK. Nosocomial infections due to Acinetobacter baumannii in a neurosurgery ICU. Neurol India 2001; 49:134-7. [PMID: 11447431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Invasive infections caused by Acinetobacter baumannii in a post-operative neurosurgery ICU were studied. Sixty one patients admitted during a span of 11 months were culture positive for acinetobacter species from blood and/or CSF samples. They were followed up prospectively for evidence of infection and clinical outcome. 40 cases had clinical evidence of infection due to acinetobacter species while in 21 patients, the isolation of the organism was considered a contaminant. Acinetobacter baumannii was the most common organism associated with invasive infections. Respiratory tract was found to be the most common primary source of infection in patients with bacteraemia or meningitis. The age, sex and pre-operative hospital stay were not significantly different in the two groups (p>0.05), while post-operative hospital stay and mortality was significantly higher in patients with invasive infection (p<0.05). Acinetobacter baumannii was isolated from multiple sites (p<0.05) and repeatedly from the same site (p<0.001) in a significantly higher number of patients with invasive infections. Mortality was high in the patients infected with Acinetobacter baumannii. Even amongst the infected group, the patient shaving meningitis showed a higher mortality as compared to the patients having bacteraemia.
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Das B, Meirovitch H. Optimization of solvation models for predicting the structure of surface loops in proteins. Proteins 2001; 43:303-14. [PMID: 11288180 DOI: 10.1002/prot.1041] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A novel procedure for optimizing the atomic solvation parameters (ASPs) sigma(i) developed recently for cyclic peptides is extended to surface loops in proteins. The loop is free to move, whereas the protein template is held fixed in its X-ray structure. The energy is E(tot) = E(FF)(epsilon = nr) + summation operator sigma(i)A(i), where E(FF)(epsilon = nr) is the force-field energy of the loop-loop and loop-template interactions, epsilon = nr is a distance-dependent dielectric constant, and n is an additional parameter to be optimized. A(i) is the solvent-accessible surface area of atom i. The optimal sigma(i) and n are those for which the loop structure with the global minimum of E(tot)(n, sigma(i)) becomes the experimental X-ray structure. Thus, the ASPs depend on the force field and are optimized in the protein environment, unlike commonly used ASPs such as those of Wesson and Eisenberg (Protein Sci 1992;1:227-235). The latter are based on the free energy of transfer of small molecules from the gas phase to water and have been traditionally combined with various force fields without further calibration. We found that for loops the all-atom AMBER force field performed better than OPLS and CHARMM22. Two sets of ASPs [based on AMBER (n = 2)], optimized independently for loops 64-71 and 89-97 of ribonuclease A, were similar and thus enabled the definition of a best-fit set. All these ASPs were negative (hydrophilic), including those for carbon. Very good (i.e., small) root-mean-square-deviation values from the X-ray loop structure were obtained with the three sets of ASPs, suggesting that the best-fit set would be transferable to loops in other proteins as well. The structure of loop 13-24 is relatively stretched and was insensitive to the effect of the ASPs.
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Choudhury RC, Das B, Misra S, Jagdale MB. Cytogenetic toxicity of vincristine. J Environ Pathol Toxicol Oncol 2001; 19:347-55. [PMID: 11213016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
The anticancer drugs vincristine sulphate (VCR) and cyclophosphamide (CTX) were tested for their cytogenetic effects in the bone marrow cells of Swiss mice. The end points investigated were chromosomal aberrations and mitotic index at 24 hours posttreatment and micronuclei (MN) at 30 hours posttreatment in bone marrow cells of male and female mice after a single intraperitoneal exposure. The doses tested were VCR 0.25, 0.5, and 1.0 mg/kg and CTX 40 mg/kg b.w. of mice. Significant percentages of chromosomal aberrations and significant numbers of micronuclei per thousand polychromatic erythrocytes (PCEs) that were induced were recorded from bone marrow of each of the VCR-treated groups of mice. There were no significant differences between the percentages of dividing cells in the VCR-treated group and the vehicle control groups of mice. Peculiarly, in the chromosomal aberration study, the male mice were found to be more responsive to VCR than the females, and the aberrations per hundred metaphases were found to be decreased when the dose of VCR was increased. The percentage of dividing cells was also higher with the lowest dose of VCR tested. However, there was a dose-dependent, but nonlinear, increase in MN per thousand PCEs. The results were compared with the already available fragmentary and self-contradictory data on the genotoxicity of VCR in mice and in other mammalian test systems.
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Mosteller R, Han J, Das B, Broek D. Biochemical analysis of regulation of Vav, a guanine-nucleotide exchange factor for Rho family of GTPases. Methods Enzymol 2001; 325:38-51. [PMID: 11036590 DOI: 10.1016/s0076-6879(00)25429-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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197
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Das B, Sengupta AK. Evaluation of low back pain risks in a beef skinning operation. INTERNATIONAL JOURNAL OF OCCUPATIONAL SAFETY AND ERGONOMICS 2001; 6:347-61. [PMID: 11082550 DOI: 10.1080/10803548.2000.11076460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The low back pain risks in a beef skinning operation at a high stand kill floor workstation was evaluated. The increases in compressive forces at lower back (L5/S1) between normal slump (back angle 25 degrees, measured in the sagittal plane) and severe (45 degrees ) and between normal slump and very severe (70 degrees ) bent back postures were 387 N or 28% and 616 N or 45%, respectively. The high spine load coupled with high level of repetition can have a high probability of fatigue failure in the spine structural members. Non-neutral back posture for a large portion of the total work time can be a low back pain risk factor. The videotape analysis showed that the times involved during the task performance for the bent back (more than 25 degrees ) and severe bent back (more than 45 degrees ) were 48.4 and 33.5% of the total cycle time, respectively. The upper limit from OWAS (Ovako Working Posture Analysis System) for bent back posture is 30% of the total cycle time. The bent and twisted back posture (both more than 25 degrees ) time was 10.4% compared to OWAS limit of 5%. This indicated that actions are needed in the near future to alleviate the risk of low back pain. Ergonomics redesign of the workstation was recommended for the operation.
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Abstract
BACKGROUND Photodynamic therapy (PDT) utilizes photosensitizers and light. Whereas PDT use in cancer treatment has been widely accepted, antimicrobial PDT (APDT) is still in its early stages of development. OBJECTIVES To study microbial killing in vitro using APDT. METHODS We used a combination of methylene blue and visible light, and a range of microbial species representative of those encountered on the skin in health and disease. Using standard light intensity conditions (slide projector, 25 cm distance from target, 42 mW cm(-2)) and methylene blue dye at 100 microg mL(-1), kill rates and subsequent D-values were determined against Staphylococcus aureus, S. epidermidis, Streptococcus pyogenes, Corynebacterium minutissimum, Propionibacterium acnes and Candida albicans. RESULTS D-values for these species were 72, 66, 48, 120, 30 and 660 s, respectively. The effects of light intensity on the killing of S. epidermidis showed the kill rate to be proportional to the light intensity. A high rate of cell kill was also obtained using natural sunlight. CONCLUSIONS Overall, these results indicate that APDT of the skin may represent a useful alternative to conventional antimicrobial treatment.
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Boral A, Ray S, Das B, Ghosh LK, Gupta BK. Computer supported studies on design and evaluation of solid dispersions of carbamazepine. BOLLETTINO CHIMICO FARMACEUTICO 2001; 140:28-31. [PMID: 11338773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
The main advantages of solid dispersions (the drug could be maintained in a bioavailable form, dosage reduction and cleaner manufacturing conditions) provide scope for the continued interest in field. Additionally, their use in providing a sustained or controlled release of drugs has only been tentatively examined. In the present study, Carbamazepine has been used to develop a dosage form which will provide a booster amount followed by sustained release of the drug for effective control of epileptic seizures while keeping the serum level of the drug at minimum. Enteric polymers CAP and CAT have been used to retard the release till the formulation reaches the intestine. Either individually or combined fractions of the formulations may be used in the therapy of epilepsy.
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