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Mukherjee SC, Basu AK, Bandyopadhyay R, Pal SK, Bandopadhyay D, Mandal SK. Correlation of lipid profile and carotid artery plaque as detected by Doppler ultrasound in ischaemic stroke patients--A hospital-based study. J Indian Med Assoc 2006; 104:325-6, 330. [PMID: 17058551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Stroke is one of the leading causes of morbidity and mortality all over the world. Carotid plaque formation and intima media thickness can be a predictor of ischaemic stroke. In this regard studies from our country, are few and far between. This is a small hospital-based study to look in to this matter. We have assessed the intima media thickness of the common carotid as well as the internal and external carotid arteries by the ultrasound method. The lipid profiles were estimated and correlated with the intima media thickness. Results indicate that in the common as well as in the internal and external carotid arteries, the intima media thickness is a good predictor of ischaemic stroke. This thickness is also well correlated with the lipid levels in blood. Hence this non-invasive method can be used successfully to identify the high risk patients, prone to develop stroke.
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Affiliation(s)
- S C Mukherjee
- Department of Medicine, Medical College, Kolkata 700073
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52
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Bandyopadhyay SK, Bandyopadhyay R, Dutta A. Isolated massive thyroid metastasis in lung cancer. Singapore Med J 2006; 47:324-6. [PMID: 16572246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Metastasis to the thyroid gland is rare despite its rich vascular supply. Among the pulmonary malignancies metastasising to the thyroid, adenocarcinomas are the commonest. The appearance of metastatic disease in lung carcinoma indicates a poor prognosis and the average survival is two months. We report a 62-year-old woman with squamous cell carcinoma of lung metastatic to the thyroid that produced massive enlargement of the gland. The appearance of the secondary preceded the diagnosis of the primary malignancy by a few months. Ultimately, the patient succumbed to her disease.
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Affiliation(s)
- S K Bandyopadhyay
- Department of Medicine, Nil Ratan Sircar Medical College and Hospital, Calcutta.
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Basu AK, Pal SK, Saha S, Bandyopadhyay R, Mukherjee SC, Sarkar P. Risk factor analysis in ischaemic stroke: a hospital-based study. J Indian Med Assoc 2005; 103:586, 588. [PMID: 16570759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Stroke represents a major health burden in our country. Ischaemic stroke has got several risk factors associated with increased chance of atherosclerosis. A small hospital-based study was done to look into the risk factors associated with ischaemic stroke. Forty patients with CT-confirmed cerebral infarction were taken for the study and detailed history and clinical findings were obtained. Investigations like complete haemogram, fasting blood glucose, urea, creatinine, lipid profile, serum Lp(a), homocysteine, fibrinogen, ECG, chest x-ray, echocardiography, MRI/MRA where indicated, were done to identify the risk factors as well. Results indicated that hypertension was the most prevalent (87.5%) risk factor followed by ischaemic heart disease (35%) and diabetes. Dyslipidaemia was also found in a significant number of cases, mostly elevated LDL, low HDL and elevated Lp(a). Fibrinogen and homocysteine were of less significance.
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Affiliation(s)
- A K Basu
- Diabetes & Endocrinology Unit, Department of Medicine, Medical College and Hospital, Kolkata
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Navi SS, Bandyopadhyay R, Reddy RK, Thakur RP, Yang XB. Effects of Wetness Duration and Grain Development Stages on Sorghum Grain Mold Infection. Plant Dis 2005; 89:872-878. [PMID: 30786520 DOI: 10.1094/pd-89-0872] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Grain mold caused by a complex of fungi is an economically important disease of sorghum worldwide. Little is known about the epidemiology of sorghum grain mold, which is essential for its management. Studies were conducted to quantify the effects of wetness duration on grain mold development under controlled conditions at ICRISAT. Six major sorghum grain mold fungi determined from previous field experiments, Curvularia lunata, Cladosporium oxysporum, Bipolaris australiensis, Fusarium moniliforme, F. pallidoroseum, and Phoma sorghina, were used. Panicles of a pot-grown mold-susceptible sorghum line, IS 10513, were spray inoculated with each fungus at five growth stages: flowering (F), milk (M), soft dough (S), hard dough (H), and physiological maturity (P), and were incubated in dew chambers for 0, 16, 24, 40, 48, and 72 h. Then, the plants were placed on greenhouse benches at 25 ± 1°C to allow grain mold infection to develop. Eight days after treatments, grains from F, M, and S stages were plated onto potato dextrose agar, while those from H and P stages were incubated in blotter paper humid chambers at 28 ± 1°C. Fungal colonization of grains were scored after 7 days. Results indicated a significant (P < 0.01) correlation between wetness duration and grain mold development at different stages of inoculation. Generally, with increasing wetness duration, there was an increase in grain infection by all six fungi. However, infection frequency varied among fungi and grain development stages, indicating that individual fungi might have different windows for maximum infection during the grain development stages.
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Affiliation(s)
- S S Navi
- Plant Pathology Department, 351 Bessey Hall, Iowa State University (ISU), Ames 50011, USA
| | - R Bandyopadhyay
- International Institute of Tropical Agriculture, PMB 5320, Ibadan, Nigeria
| | - R K Reddy
- International Crops Research Institute for the Semi-Arid Tropics, Patancheru, P.O. Andhra Pradesh, 502 324, India
| | - R P Thakur
- International Crops Research Institute for the Semi-Arid Tropics, Patancheru, P.O. Andhra Pradesh, 502 324, India
| | - X B Yang
- Plant Pathology Department, 351 Bessey Hall, ISU, Ames 50011, USA
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55
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Bandyopadhyay R, Liang D, Yardimci H, Sessoms DA, Borthwick MA, Mochrie SGJ, Harden JL, Leheny RL. Evolution of particle-scale dynamics in an aging clay suspension. Phys Rev Lett 2004; 93:228302. [PMID: 15601124 DOI: 10.1103/physrevlett.93.228302] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2004] [Indexed: 05/24/2023]
Abstract
Multispeckle x-ray photon correlation spectroscopy was employed to characterize the slow dynamics of a suspension of highly charged, nanometer-sized disks. At wave vectors q corresponding to interparticle length scales, the dynamic structure factor follows a form f(q,t) approximately exp([-(t/tau)(beta)], where beta approximately 1.5. The relaxation time tau increases with the sample age t(a) approximately as tau approximately t(1.8)(a) and decreases with q as tau approximately q(-1). Such behavior is consistent with models that describe the dynamics in disordered elastic media in terms of strain from random, local structural rearrangements. The measured amplitude of f(q,t) varies with q in a manner that implies caged particle motion. The decrease in the range of this motion and an increase in suspension conductivity with increasing t(a) indicate a growth in interparticle repulsion as the mechanism for internal stress development implied by these models.
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Affiliation(s)
- R Bandyopadhyay
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
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56
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Basu AK, Bandyopadhyay D, Bandyopadhyay R, Majumdar D, Chakrabarty PP. Insulin in type 2 diabetes: promises to keep. J Indian Med Assoc 2004; 102:438, 440, 442 passim. [PMID: 15719806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
The concept which has evolved in the management of type 2 diabetes mellitus is early insulin therapy. In type 2 diabetes mellitus first phase insulin response is grossly impaired on eventually absent, overburdening phase 2 responses which obviously fail to compensate in the long run. Perpetuation of the age old practice to continue OHA while almost all beta-cells are exhausted is only buying time for starting insulin. Preservation of beta-cell function by early insulin therapy yields two important benefits: (1) Better glycaemic control at lower medication dose and (2) relative freedom from hypoglycaemia because of well preserved glucagon response. To ensure and to translate the proper action of insulin in the target organs we are now talking about designer insulins which are basically insulin analogues (short and long acting). So type 2 diabetes is a growing menace and is responsible for severe morbidity, mortality and poor quality of life. Good glycaemic control from the very beginning of diabetes has shown to favourably influence all of these and is accepted as a cardinal goal of proper diabetes care.
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Affiliation(s)
- A K Basu
- Department of Medicine, Medical College, Kolkata 700073
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57
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Bandyopadhyay D, Basu AK, Mandal SK, Bandyopadhyay R, Pal SK, Chakraborty PP, Bose S. Glycaemic consequences of HIV and highly active antiretroviral therapy: a pilot study and review of literature. J Indian Med Assoc 2004; 102:453-6. [PMID: 15719808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
The metabolic consequences of HIV and AIDS are accentuated in the setting of highly active antiretroviral therapy. Peripheral lipodystrophy, central adiposity, hyperlipidaemia, insulin resistance and diabetes mellitus are frequent associations of protease inhibitor containing highly active antiretroviral therapy regimens. Ninety patients aged 25-50 years (males 52, females 38), seropositive for HIV 1 and 2 or both were selected to see the glycaemic profiles in asymptomatic early HIV disease with CD4 counts > 100/microl and to compare this with the glycaemic profile of (a) advanced HIV disease (CD4 counts < 200/microl), not on highly active antiretroviral therapy and (b) advanced HIV disease (CD4 counts < 200/microl), on uninterrupted non-protease inhibitor highly active antiretroviral therapy > 6 months. All the patients were grouped into 3: (1) Group A: CD4 counts > 500/microl (n=37), highly active antiretroviral therapy naive, (2) group B: CD4 counts < 200/microl (n=21), not on highly active antiretroviral therapy, and (3) group C: CD4 counts < 200/microl, receiving uninterrupted non-protease inhibitor based highly active antiretroviral therapy for > 6 months (n=32). The fasting blood glucose, glycosylated Hb (HbA1c) levels, were measured in all the patients in 3 groups and significance of difference between means was calculated among various groups. Body weight and waist-hip ratio were also measured. The results were analysed and compared with other studies.
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Hess DE, Bandyopadhyay R, Sissoko I. Pattern Analysis of Sorghum Genotype × Environment Interaction for Leaf, Panicle, and Grain Anthracnose in Mali. Plant Dis 2002; 86:1374-1382. [PMID: 30818444 DOI: 10.1094/pdis.2002.86.12.1374] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Resistance to anthracnose, caused by Colletotrichum graminicola, in sorghum was identified through field screening at two locations (Samanko and Longorola) in Mali. The occurrence and progress of anthracnose were monitored on 19 sorghum lines plus resistant and susceptible checks in the 1996 to 1998 rainy seasons. Foliar anthracnose severity was assessed at regular intervals throughout the season. Area under the disease progress curve (AUDPC) was calculated for each genotype. Anthracnose severity was also evaluated on the peduncle, rachis and glumes, panicle, and grain. For the characters under study, the site × year and site × year × line interactions accounted for the genotype × environment interactions. Pattern analysis was applied to the environment-standardized matrix of genotype × environment means to analyze these interactions and elucidate genotypic adaptation. None of the lines was completely (hypersensitive) resistant to the disease, but 12 showed high levels of stable resistance to both foliar and panicle anthracnose. Only one was moderately susceptible to both forms of the disease. In addition to identifying varieties that can be grown in zones to which they are adapted, additional genotypes were identified that can serve as sources of resistance in regional breeding programs.
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Affiliation(s)
- D E Hess
- Principal Plant Pathologist, ICRISAT, B.P. 320, Bamako, Mali
| | - R Bandyopadhyay
- Principal Plant Pathologist, ICRISAT, Patancheru 502 324, Andhra Pradesh, India
| | - I Sissoko
- Scientific Officer, ICRISAT, B.P. 320, Bamako, Mali
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Ganguli S, Bandyopadhyay R, Chakraborty S. Adrenal steroids act as inhibitory modulators of thyrofollicular cell morphology and proliferation in neonatal chicks (Gallus domesticus). Folia Biol (Praha) 2002; 49:259-63. [PMID: 11987466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
In the present study the effects of adrenal corticoids, both natural and synthetic, namely cortisol and dexamethasone respectively, was observed on the thyroid gland cell morphology and proliferation in neonatal male chicks (Gallus domesticus). Cortisol was injected at a dose of 4 mg/100 g body weight and dexamethasone at a dose of 1 mg/100 g b.w. subcutaneously daily for fifteen consecutive days. The control birds were similarly injected with normal saline at a daily dose of 0.2 ml per bird for the same time period. The results indicated that both cortisol and dexamethasone caused a significant decrease in thyrofollicular cell height. On the contrary, a significant increase in the ratio of the follicular diameter to the number of nuclei per follicle i.e. D/N value was observed in both cortisol and dexamethasone treated chicks. It was also observed that both cortisol and dexamethasone induced suppression of mitotic activity, as evidenced from a significant decrease in mitotic percentage compared with the control chicks. The present authors' studies thus indicate that adrenal corticoids act as inhibitory modulators of thyroid follicular activity as regards karyomorphology and cell proliferation.
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Affiliation(s)
- S Ganguli
- Pineal Research Unit, Department of Zoology, University of Calcutta, 35 Ballygunge Circular Road, Calcutta 700 019, India.
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60
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Bandyopadhyay SK, Bandyopadhyay R, Chatterjee U. Isolated gastric tuberculosis presenting as haematemesis. J Postgrad Med 2002; 48:72-3. [PMID: 12082338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
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Bandyopadhyay R, McQuillan C, Page SL, Choo KH, Shaffer LG. Identification and characterization of satellite III subfamilies to the acrocentric chromosomes. Chromosome Res 2001; 9:223-33. [PMID: 11330397 DOI: 10.1023/a:1016648404388] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The centromeres and the short arms of the five pairs of acrocentric chromosomes in humans are composed of tandemly ordered repetitive DNA. Previous studies have suggested that the exchanges between acrocentric chromosomes have resulted in concerted evolution of different DNA sequences in their short arms. The acrocentric chromosomes are clinically relevant since they are involved in Robertsonian translocation formation and non-disjunction resulting in aneuploidy. Here we have identified seven new satellite III repetitive DNA subfamilies, determined their nucleotide sequences and established their chromosomal distributions on the short arms of the acrocentric chromosomes. Knowledge of these related sequences may help to elucidate the molecular basis of Robertsonian translocation formation.
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Affiliation(s)
- R Bandyopadhyay
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
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62
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Bandyopadhyay R, Berend SA, Page SL, Choo KH, Shaffer LG. Satellite III sequences on 14p and their relevance to Robertsonian translocation formation. Chromosome Res 2001; 9:235-42. [PMID: 11330398 DOI: 10.1023/a:1016652621226] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Robertsonian translocations (ROBs) are the most common rearrangements in humans, contributing significantly to genetic imbalance, fetal wastage, mental retardation and birth defects. Rob(14q21q) and rob(13q14q), which are formed predominantly during female meiosis, comprise the majority (approximately 85%) of all ROBs. Previous studies have shown that the breakpoints are consistently located within specific regions of the proximal short arms of chromosomes 13, 14, and 21. The high prevalence of these translocations, the consistent breakpoints found, and the fact that roughly 50% of cases occur sporadically suggest that the sequences at or near the breakpoints confer susceptibility to chromosome rearrangement and that the rearrangements occur through a specific mechanism. To investigate this hypothesis, we developed hamster-human somatic cell hybrids derived from de novo rob(14q21q) patients that contained the translocated chromosome segregated from the other acrocentric chromosomes. We determined the physical order of five satellite III subfamilies on 14p, and investigated their involvement in formation of these de novo translocations.
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Affiliation(s)
- R Bandyopadhyay
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
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63
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Boosalis MS, Bandyopadhyay R, Bresnick EH, Pace BS, Van DeMark K, Zhang B, Faller DV, Perrine SP. Short-chain fatty acid derivatives stimulate cell proliferation and induce STAT-5 activation. Blood 2001; 97:3259-67. [PMID: 11342457 PMCID: PMC4263369 DOI: 10.1182/blood.v97.10.3259] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Current chemotherapeutic and butyrate therapeutics that induce fetal hemoglobin expression generally also suppress erythropoiesis, limiting the production of cells containing fetal hemoglobin (F cells). Recently, selected short-chain fatty acid derivatives (SCFADs) were identified that induce endogenous gamma-globin expression in K562 cells and human burst-forming units-erythroid and that increase proliferation of human erythroid progenitors and a multilineage interleukin-3-dependent hematopoietic cell line. In this report, gamma-globin inducibility by these SCFADs was further demonstrated in mice transgenic for the locus control region and the entire beta-globin gene locus in a yeast artificial chromosome and in 2 globin promoter-reporter assays. Conditioned media experiments strongly suggest that their proliferative activity is a direct effect of the test compounds. Investigation of potential mechanisms of action of these SCFADs demonstrates that these compounds induce prolonged expression of the growth-promoting genes c-myb and c-myc. Both butyrate and specific growth-stimulatory SCFADs induced prolonged signal transducer and activator of transcription (STAT)-5 phosphorylation and activation, and c-cis expression, persisting for more than 120 minutes, whereas with IL-3 alone phosphorylation disappeared within minutes. In contrast to butyrate treatment, the growth-stimulating SCFADs did not result in bulk histone H4 hyperacetylation or induction of p21(Waf/Cip), which mediates the suppression of cellular growth by butyrate. These findings suggest that the absence of bulk histone hyperacetylation and p21 induction, but prolonged induction of cis, myb, myc, and STAT-5 activation, contribute to the cellular proliferation induced by selected SCFADs.
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Affiliation(s)
- M S Boosalis
- Department of Medicine, Cancer Research Center and Hemoglobinopathy-Thalassemia Research Unit, Boston University School of Medicine, Boston, MA, USA
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Abstract
A novel algorithm for PID controllers based on dead-beat control and fuzzy inference mechanism is presented in this paper. The proposition is an extension of the work by the authors where the PI form of the algorithm was presented. The inclusion of the derivative term makes the method suitable for application in all types of processes including the ones having high rate disturbances. The proposed algorithm seems to be a complete and generalized PID autotuner as can be seen by the simulated and experimental results. In all the cases the method shows substantial improvement over the controller tuned with Ziegler Nichol's formula and the PI controller proposed in R. Bandyopadhyay, D. Patranabis, A fuzzy logic based PI autotuner, ISA Transactions 37 (1998) 227-235.
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Affiliation(s)
- R Bandyopadhyay
- Department of Instrumentation Engineering, Jadavpur University, Calcutta, India.
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Abstract
Plant diseases are a significant constraint to agricultural productivity. Exotic plant diseases pose a continued threat to profitable agriculture in the United States. The extent of this threat has increased dramatically in the 1980s and 1990s due to the expansion of international trade in agricultural products and frequent movement of massive volume of people and goods across national boundaries. Introduction of new diseases has not only caused farm losses, but has also diminished export revenue since phytosanitary issues are linked to international commerce. Plant pathogens and their vectors have also moved across national boundaries, sometimes naturally and at other times influenced by the recent changes in trade practices. Sorghum ergot, Karnal bunt of wheat, potato late blight, and citrus tristeza are some of the most recent examples of enhanced importance of diseases due to the introduction of plant pathogens or vectors.
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Affiliation(s)
- R Bandyopadhyay
- International Crops Research Institute, Semi-Arid Tropics (ICRISAT), Patancheru, India.
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Bandyopadhyay R, Grant DJ. Influence of crystal habit on the surface free energy and interparticulate bonding of L-lysine monohydrochloride dihydrate. Pharm Dev Technol 2000; 5:27-37. [PMID: 10669915 DOI: 10.1081/pdt-100100516] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The objective of the present study was to apply a technique to measure the surface energy of crystalline powders without changing the surface properties by compaction, and to relate such measurements to crystal habit and orientation. The surface free energy of uncompacted L-lysine monohydrochloride dihydrate (LH), determined using a modified sessile-drop method, reflected a combined value for the various faces, and was influenced by the relative size of the faces and the orientation of the crystals. The surface free energy values obtained from contact angle measurements were within the possible range calculated from the crystal structure. Discrepancies between the theoretical estimates of interparticulate cohesive strengths and those measured from the tensile strength of powder compacts were used to estimate the flaw sizes (or gaps between the particles) that act as stress concentrators and reduce the tensile strength of the compacts. The flaw sizes indicate packing and compressibility of the various crystal habits. In the absence of compressive load, compacts made out of the equidimensional crystals have the larger flaw sizes (wider cracks or wider gaps between the particles). At higher compaction pressures, the compacts from long rod-shaped crystals have longer crack lengths. The weakness of the compacts made from the long rods at the higher compaction pressures may be because of the longer crack length along the interparticulate boundary, which may result in a higher stress intensity at the crack tip and increased fracture propensity.
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Affiliation(s)
- R Bandyopadhyay
- Department of Pharmaceutics, College of Pharmacy, University of Minnesota, Minneapolis 55455-0343, USA
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Bandyopadhyay R, Basappa G, Sood AK. Observation of chaotic dynamics in dilute sheared aqueous solutions of CTAT. Phys Rev Lett 2000; 84:2022-2025. [PMID: 11017686 DOI: 10.1103/physrevlett.84.2022] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/1999] [Indexed: 05/23/2023]
Abstract
The nonlinear flow behavior of a viscoelastic gel formed due to entangled, cylindrical micelles in aqueous solutions of the surfactant cetyl trimethylammonium tosilate (CTAT) has been studied. On subjecting the system to a step shear rate lying above a certain value, the shear and normal stresses show interesting time dependent behavior. The analysis of the measured time series shows the existence of a finite correlation dimension and a positive Lyapunov exponent, unambiguously implying that the dynamics can be described by that of a dynamical system with a strange attractor whose dimension increases with the increase in shear rate.
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Affiliation(s)
- R Bandyopadhyay
- Department of Physics, Indian Institute of Science, Bangalore 560 012, India
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68
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Abstract
The alternate pathway of signal transduction via hydrolysis of phosphatidylcholine, the major cellular phospholipid, has been investigated in murine peritoneal macrophages. A sustained formation of diacylglycerol, is preceded by an enhanced production of phosphatidic acid, when the macrophages were given a stimulus with 12-O-tetradecanoyl phorbol-13-acetate for sixty minutes. Production of choline and choline metabolites are significantly increased too. Propranolol, which inhibits phosphatidate phosphohydrolase, the enzyme responsible for conversion of phosphatidic acid to diacylglycerol, can effectively block the formation of diacylglycerol. Inhibition of protein kinase C either by its inhibitors, staurosporine and H-7 or by depletion, apparently affect the generation of the lipid products. Moreover, based on the results of transphosphatidylation reaction, involvement of a phospholipase D in the phosphatidylcholine-hydrolytic pathway in macrophages is predicted. These observations support the view that probably the phorbol ester acting directly on protein kinase C of the macrophages activate their phosphatidylcholine-specific phospholipase D to allow a steady generation of second messengers, to enable them to participate in the cell signalling process in a more efficient manner than those generated in the phosphoinositide pathway of signal transduction.
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Affiliation(s)
- R Bandyopadhyay
- Biomembrane Division, Indian Institute of Chemical Biology, Calcutta
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69
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Bellaïche Y, Bandyopadhyay R, Desplan C, Dostatni N. Neither the homeodomain nor the activation domain of Bicoid is specifically required for its down-regulation by the Torso receptor tyrosine kinase cascade. Development 1996; 122:3499-508. [PMID: 8951065 DOI: 10.1242/dev.122.11.3499] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Bicoid (Bcd) is a maternal morphogen responsible for patterning the head and thorax of the Drosophila embryo. Correct specification of head structure, however, requires the activity of the Torso receptor tyrosine kinase cascade, which also represses expression of Bcd targets at the most anterior tip of the embryo. Here, we investigate the role of both the homeodomain (HD) and the activation domain of Bcd in the anterior repression of its targets. When a Bcd mutant protein whose HD has been replaced by the Gal4 DNA-binding domain is expressed in early embryos, a reporter gene driven by Gal4 DNA-binding sites is first activated in an anterior domain and then repressed from the anterior pole. The down-regulation of Bcd-Gal4 activity requires torso function but does not depend on endogenous bcd activity, indicating that the Bcd protein alone and none of its targets is required to mediate the effect of torso. Functional analysis of a chimeric protein, whose activation domain has been replaced by a generic activation domain, indicates that the activation domain of Bcd is also not specifically required for its down-regulation by Torso. We propose that Torso does not affect the ability of Bcd to bind DNA, but instead directs modification of Bcd or of a potential Bcd co-factor, which renders the Bcd protein unable to activate transcription.
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Affiliation(s)
- Y Bellaïche
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10021, USA
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Singh PS, Bandyopadhyay R, Rao BS. Characterization of SAPO-11 synthesized conventionally and in the presence of fluoride ions. ACTA ACUST UNITED AC 1996. [DOI: 10.1039/ft9969202017] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Silverstein JH, Bandyopadhyay R. Camping with a friend. Helping adolescents cope with diabetes. J Fla Med Assoc 1995; 82:817-20. [PMID: 8568506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The Florida Camp for Children and Youth With Diabetes sponsored a weekend in which teenagers with diabetes invited a friend of the same sex without diabetes to participate in a two-day retreat. This program was designed to encourage friends to take an active role in motivating the teen with diabetes to perform his or her diabetes-related tasks in a responsible manner. Forty-six patients ranging in age from 12-17 years brought friends. Those with diabetes participated in rap sessions as well as educational sessions attempting to teach independence in self-care. The friends were taught the basics of diabetes as well as given an opportunity to inject saline and monitor their own blood glucose levels. A choice of activities was interspersed with education.
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Affiliation(s)
- J H Silverstein
- Department of Pediatrics, University of Florida College of Medicine, Gainesville, USA
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Dutta M, Bandyopadhyay R, Basu MK. Neoglycosylated liposomes as efficient ligands for the evaluation of specific sugar receptors on macrophages in health and in experimental leishmaniasis. Parasitology 1994; 109 ( Pt 2):139-47. [PMID: 8084660 DOI: 10.1017/s0031182000076253] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Receptors interacting with terminal sugars as ligands are involved in the binding of Leishmania donovani promastigotes to the macrophage surface and their subsequent internalization. Mannose and glucose are specifically involved in the binding process. Decreased binding occurs to macrophages already infected with L. donovani either in vivo or in vitro. When mannose- or glucose-bearing liposomes are used as ligands the binding shows similar trends and the percentage inhibition of binding with mannose-bearing liposomes increases when compared to that for the glucose-bearing ones. The decreased binding of the ligand seems to be due to a decrease in the number of receptors after infection. The affinity of the ligands for the binding sites either on the normal macrophages or on the infected macrophages apparently remains the same. The results based on the incorporation of [3H]phenyl alanine and supported by the binding of glycosylated liposomes to both infected and non-infected macrophages suggest that protein synthesis, in general, is suppressed in L. donovani-infected macrophages thus affecting also mannose/glucose receptor protein synthesis, resulting in fewer receptors on the macrophage surface.
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Affiliation(s)
- M Dutta
- Biomembrane Division, Indian Institute of Chemical Biology, Calcutta
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74
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Abstract
The DNA adenine methyltransferase (MTase)-encoding gene (dam) of Vibrio cholerae, an organism belonging to the family Vibrionaceae, has been cloned and the complete nucleotide (nt) sequence determined. V. cholerae dam encodes a 21.5-kDa protein and is directly involved in methyl-directed DNA mismatch repair. It can substitute for the Escherichia coli enzyme and can suppress the phenotypic traits associated with E. coli dam mutants. Overproduction of V. cholerae Dam MTase does not result in hypermutability in either V. cholerae or E. coli cells. Overproduction of V. cholerae Dam in a pUC plasmid, however, fails to suppress the 2-aminopurine (2-AP)-sensitive phenotype of E. coli dam mutants. Homology between the nt and deduced amino acid (aa) sequences of the E. coli and V. cholerae dam genes is only 30-35%.
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Affiliation(s)
- R Bandyopadhyay
- Biophysics Division, Indian Institute of Chemical Biology, Calcutta
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75
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Abstract
A portion of the beta-actin mRNA of mammalian cells is believed to lack a poly(A) tail, because of its failure to bind to oligo(dT)-cellulose. S1 mapping and Northern blot analysis of this mRNA shows it to contain a poly(A) sequence of about 60 nucleotides. Only about 20-40 nucleotides are available for interaction with oligo(dT). The rest is masked, presumably by base-pairing with a poly(U) stretch present in the 3' non-coding region of the mRNA. A similar configuration occurs in the bulk of the actin mRNA, which carries a poly(A) tail with sizes ranging from approximately 60 to 200 nucleotides.
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Affiliation(s)
- R Bandyopadhyay
- Department of Biochemistry, Tufts University Health Sciences Schools, Boston, MA 02111
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Bandyopadhyay R, Mughogho L, Satyanarayana M, Kalisz M. Occurrence of airborne spores of fungi causing grain mould over a sorghum crop. ACTA ACUST UNITED AC 1991. [DOI: 10.1016/s0953-7562(09)80583-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Bandyopadhyay R, Coutts M, Krowczynska A, Brawerman G. Nuclease activity associated with mammalian mRNA in its native state: possible basis for selectivity in mRNA decay. Mol Cell Biol 1990; 10:2060-9. [PMID: 2325645 PMCID: PMC360553 DOI: 10.1128/mcb.10.5.2060-2069.1990] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Polysome and messenger ribonucleoprotein (mRNP) preparations from various mammalian cells contain tightly bound nuclease activity that causes degradation of the mRNA in the preparations. This activity was found to cosediment with all polysome size classes as well as with free mRNPs and to remain associated with the mRNPs released from polysomes by treatment with EDTA. No association with ribosomal subunits was evident. The rates of mRNA degradation were not affected by serial dilution, an indication that enzyme and substrate are tightly associated. beta-Globin mRNA in purified reticulocyte polysomes was cleaved at AU sequences in the 3'-terminal region. Cleavages at the same sites occurred when deproteinized reticulocyte RNA was incubated with mouse sarcoma 180 (S-180) polysomes. The S-180 preparations caused additional cleavages, primarily at UG sequences. A P40 mRNA in S-180 polysomes was cleaved primarily in the 3' noncoding region, but the cleavages in a P21 mRNA were seen in the 5' noncoding region only. Actin mRNA was cleaved in an internal region, yielding large relatively stable 3'- and 5'-terminal fragments. These data suggest the occurrence of highly specific interactions between one or more mRNA-bound nucleases and individual mRNA species.
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Affiliation(s)
- R Bandyopadhyay
- Department of Biochemistry, Tufts University Health Sciences Schools, Boston, Massachusetts 02111
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Abstract
The state of the lipid phase of the membrane plays a key role in the exposure of various receptors, antigens and enzymes on the membrane surface. The fluidity of membranes of Leishmania donovani promastigotes was monitored by two independent methods, i.e. influx of sterol from liposomes and removal of phospholipids by treatment with phospholipase C. The altered sterol/phospholipid ratio, in both cases, provided evidence that the activity of the functionally important membrane-bound enzyme Mg2(+)-ATPase is modulated by the state of the lipid phase of the membrane.
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Affiliation(s)
- M Dutta
- Biomembrane Division, Indian Institute of Chemical Biology, Calcutta
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Bandyopadhyay R, Sengupta A, Das J. A mutation in the dam gene of Vibrio cholerae: 2-aminopurine sensitivity with intact GATC methylase activity. Biochem Biophys Res Commun 1989; 165:561-7. [PMID: 2688642 DOI: 10.1016/s0006-291x(89)80003-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Vibrio cholerae mutants sensitive to 2-aminopurine (2AP) but with DNA adenine methylase activity similar to parental cells have been isolated. The mutant strains were sensitive to ultraviolet light (UV), methyl methane sulphonate (MMS) and 9-aminoacridine. The spontaneous mutation frequency of the mutants were not significantly affected. Attempts to isolate dam V. cholerae cells by screening 2AP sensitive cells have not been successful. All the mutant phenotypes could be suppressed by introducing the plasmid pRB103 carrying the dam gene of Escherichia coli into the mutant cells.
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Affiliation(s)
- R Bandyopadhyay
- Biophysics Division, Indian Institute of Chemical Biology, Calcutta
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Abstract
Total phospholipids were extracted from the heart, hepatopancreas, and hemolymph of the Indian horseshoe crab Carcinoscorpius rotundicauda by the conventional method. Characteristic group reaction and 2-dimensional thin-layer chromatography on silica gel were used for identification of different phospholipids. The phospholipid profile obtained from hemolymph and 2 major organs are comparable and show phosphatidyl choline (PC) and phosphatidyl ethanolamine to be the major phospholipids. A phospholipid has been consistently detected migrating immediately below the PC in the thin-layer chromatogram of lipids extracted from the hepatopancreas. When mixed methyl esters of this slower moving PC are resolved on a silica gel plate ran in hexane ether:acetic acid 80:20:1, with appropriate controls, an additional spot is seen just below the normal methyl ester, indicating a difference between the fatty acid compositions of 2 PC (e.g., regular and slower). The slower mixed methyl esters were found to comprise mainly the 4 saturated fatty acids: lauric, myristic, palmitic, and stearic. The slow moving PC seems to consist mainly of molecular species with the above-mentioned saturated fatty acids at both Sn 1 and Sn 2 positions.
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Affiliation(s)
- R Bandyopadhyay
- Biomembrane Division, Indian Institute of Chemical Biology, Calcutta
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Chitpatima ST, Makrides S, Bandyopadhyay R, Brawerman G. Nucleotide sequence of a major messenger RNA for a 21 kilodalton polypeptide that is under translational control in mouse tumor cells. Nucleic Acids Res 1988; 16:2350. [PMID: 3357792 PMCID: PMC338237 DOI: 10.1093/nar/16.5.2350] [Citation(s) in RCA: 123] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- S T Chitpatima
- Department of Biochemistry, Tufts University Health Sciences Schools, Boston, MA 02111
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Makrides S, Chitpatima ST, Bandyopadhyay R, Brawerman G. Nucleotide sequence for a major messenger RNA for a 40 kilodalton polypeptide that is under translational control in mouse tumor cells. Nucleic Acids Res 1988; 16:2349. [PMID: 3357791 PMCID: PMC338236 DOI: 10.1093/nar/16.5.2349] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- S Makrides
- Department of Biochemistry, Tufts University Health Sciences Schools, Boston, MA 02111
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Bandyopadhyay R, Stein G, Stein J. Coordinate turnover of nuclear and cytoplasmic histone messenger RNA following inhibition of DNA replication in HeLa S3 cells. Biochemistry 1987; 26:2938-44. [PMID: 3038171 DOI: 10.1021/bi00384a040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
We have examined the metabolism of human H4 histone mRNA in the nucleus and cytoplasm of HeLa S3 cells following inhibition of DNA synthesis to address the extent to which histone mRNA stability in these cellular compartments is coupled to DNA replication. The nuclear and cytoplasmic levels of histone mRNAs encoded by the pF0108A human H4 histone gene were determined by S1 nuclease analysis using a 32P-labeled probe that could distinguish pF0108A transcripts from those of other members of the H4 histone multigene family. Hydroxyurea treatment resulted within 15 min in a 75% reduction in the level of histone H4 mRNA in the nucleus, which corresponds to the 85% decrease observed for H4 histone mRNA in the cytoplasm. The kinetics of nuclear and cytoplasmic H4 mRNA turnover following hydroxyurea treatment were also similar. Northern blot analysis using a 32P-labeled mitochondrial cytochrome b probe indicated that the association of cytoplasmic RNA with the nuclear fraction was less than 0.5%. Treatment of cells with a protein synthesis inhibitor resulted in a 1.3-fold increase in nuclear H4 histone mRNA levels and a 1.5-fold increase of H4 mRNA in the cytoplasm after 45 min. Together, these results indicate that nuclear and cytoplasmic H4 histone mRNAs respond similarly to metabolic perturbations that influence message stability and that mechanisms operative in the turnover of histone mRNAs in the nucleus and cytoplasm may be similar.
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Abstract
Using S1 nuclease protection assays, we have examined the representation of cell cycle-dependent H4 histone RNAs in the nuclear matrix and nonmatrix nuclear fractions of human cells. Cytoplasmic and nuclear fractions were prepared from exponentially growing HeLa S3 cells by double detergent (sodium deoxycholate and NP40) lysis. The nuclear matrix and nonmatrix nuclear fractions were then prepared by digestion of nuclei with RNase-free DNase I and subsequent high-salt [0.4 M (NH4)2SO4] extraction. Subcellular fractions were characterized by 1) DNA, RNA, and protein composition; 2) electrophoretic analysis of the proteins in each fraction; 3) the representation of 45S ribosomal RNA precursors and processed 18S and 28S ribosomal RNAs; and 4) the presence of mitochondrial RNAs. In contrast to ribosomal and messenger RNA precursors, which are largely associated with the nuclear matrix, the human H4 histone RNAs in the nucleus were found predominantly in the nonmatrix nuclear fraction. The presence of H4 histone RNA in the nonmatrix nuclear fraction appeared to be coupled to DNA replication, since inhibition of DNA synthesis by hydroxyurea resulted in a loss of histone RNA from the nucleus. Our results suggest either that the association of histone RNAs with the nuclear matrix is very transient or that posttranscriptional modifications of the rapidly processed histone gene transcripts do not involve the nuclear matrix.
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Bandyopadhyay R. Inhibition of acetylcholine esterase by permethrin & its reversion by acetylthiocholine. Indian J Exp Biol 1982; 20:488-91. [PMID: 7129545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Bandyopadhyay R, Datta AG. Further studies on biosynthesis of erythropoietin. Indian J Biochem Biophys 1981; 18:241-4. [PMID: 7327602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Sarkar AK, Maitra SK, Bandyopadhyay R. Reserpine induced changes in pituitary prolactin of the female Indian koel Eudynamys scolopacea scolopacea (L). Indian J Exp Biol 1981; 19:651-2. [PMID: 7309152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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