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Biomedical subjects

S Bhattacharya

Publications and source records attributed to S Bhattacharya.

At least 55 records · Page 3Linked to original sources
PubMed2004

Analysis of differentially expressed genes in hyperthyroid-induced hypertrophied heart by cDNA microarray.

Experiments were carried out to identify the altered genes in hyperthyroid rat heart and their influence on the functions of cardiac myocytes. Chronic treatment of rats with 3,5,3' triiodo-L-thyronine (T3) resulted in a prominent increase in the size of the left ventricle with increased wall thickness and reduced chamber volume leading to concentric cardiac hypertrophy. The heart weight to body weight ratio (HW/BW) in hyperthyroid rats was increased by about 58% over that of normal rats. Using cDNA microarray comprising 588 genes, we compared the differences in mRNA expression of hyperthyroid and normal rat heart. Based on a threshold of greater than 10% change, about 37 genes were found to be regulated by T3. Further analyses by Western blotting, Northern blotting and real-time quantitative RT-PCR of some of the genes confirmed the microarray results. The T3-altered genes encode various types of proteins related to metabolism, matrix and cytoskeletal structures, growth factors, transcription factors, Ca(2+)-channels etc. The physiological significance of one of these altered proteins in hyperthyroid heart, insulin-responsive glucose transporter (GLUT) type 4 (GLUT4), was studied in detail. The expression of GLUT4 was drastically reduced in the ventricular tissues of hyperthyroid heart. Insulin-induced glucose uptake in hyperthyroid cardiomyocytes was reduced significantly, indicating the impaired glucose transport in cardiac cells. Interestingly, a few genes such as GLUT4, cytochrome P450 isoforms, superoxide dismutase (SOD), collagens, matrix metalloproteinases (MMP), tissue inhibitors of matrix metalloproteinases etc. which had not been reported earlier were found to be altered in hyperthyroid heart. Our results show some new aspects of hyperthyroid heart which will be important in assessing the pathophysiology of hypertrophied cardiomyocytes.

Animals↗
PubMed2004

Detection of slime production by coagulase-negative Staphylococcus: an assessment of two methods.

The detection of slime can be helpful in determining the diagnostic value of coagulase-negative Staphylococcus (CNS). Here, we have made a comparative study of two phenotypic methods of slime production test from 28 clinically significant blood culture isolates of CNS. A total 16 out of 28 isolates (57.1%) were positive for slime by either of the tests, whereas only 5 out of 28 isolates (17.9%) were positive for slime by both the tests. The tube method detected slime in significantly more number of isolates than the spectrophotometric method (14 vs. 7; p<0.0483279). A weak correlation was found between the tube method and the spectrophotometric method (rs=0.2474). The tube test was found to be superior to the spectrophotometric test in terms of sensitivity, ease of performance and interpretation, and cost effectiveness.

Bacteriological Techniques↗
PubMed2003

Studies on the immunogenic potential of plant-expressed cholera toxin B subunit.

Nicotiana tabacum var. Samsun was transformed via Agrobacterium-mediated transformation with a gene encoding the cholera toxin B subunit (CTB) of Vibrio cholerae, modified to contain a sequence coding for an endoplasmic reticulum retention signal (SEKDEL), under the control of the cauliflower mosaic virus 35S promoter. Total protein from the transgenic leaf tissue was isolated and an aliquot containing 5 microg recombinant CTB was injected intradermally into Balb/c (H2K(d)) mice. CTB-specific serum IgG was detected in animals that had been administered plant-expressed or native purified CTB. A T-cell proliferation study using splenocytes and cytokine estimations in supernatants generated by in vitro stimulation of macrophages isolated from the immuno-primed animals was carried out. Inhibition of proliferation of T lymphocytes was observed in splenic T lymphocytes isolated from animals injected with either native or plant-expressed CTB. Macrophages isolated from mice immunised with native or plant-expressed CTB showed enhanced secretion of interleukin-10 but secretion of lipopolysaccharide-induced interleukin-12 and tumor necrosis factor alpha was inhibited. These studies suggest that plant-expressed protein behaved like native CTB with regards to effects on T-cell proliferation and cytokine levels, indicating the suitability of plant expression systems for the production of bacterial antigens, which could be used as edible vaccine. The transgene was found to be inherited in the progeny and was expressed to yield a pentameric form of CTB as evident by its interaction with G(M1) ganglioside.

Animals↗
PubMed2003

Evaluation of antipyretic potential of Vernonia cinerea extract in rats.

The methanol extract of the whole plant of Vernonia cinerea (MEVC) was evaluated for its antipyretic potential on normal body temperature and yeast-induced pyrexia in rats. MEVC significantly reduced the normal body temperature at doses of 250 and 500 mg/kg body weight p.o. MEVC also lowered the elevated body temperature in the case of yeast-induced pyrexia in a dose dependent manner. The antipyretic effect of the extract at a dose of 500 mg/kg was identical to that of the standard drug paracetamol.

Administration, Oral↗
PubMed2003

Onset of puberty and ovarian steroidogenesis following adminstration of methanolic extract of Cuscuta reflexa Roxb. stem and Corchorus olitorius Linn. seed in mice.

The effect of methanolic extract (ME) of Cuscuta reflexa stem Roxb. and Corchorus olitorius Linn. seed on the onset of reproductive maturity and the ovarian steroidogenesis was studied by means of biochemical techniques. ME of Cuscuta reflexa stem and Corchorus olitorius seed treatment causes a remarkable delay in sexual maturation as evidenced by the age at vaginal opening and appearance of first estrus (cornified smear). The same treatment also results in a significant diminution of Delta(5)-3beta-hydroxysteroid dehydrogenase (HSD) and glucose-6-phosphate dehydrogenase (G-6-PD) activity along with a reduction in the weight of ovary, uterus and pituitary. On the basis of above data, it is assumed that the probable cause of delayed maturation in ME of Cuscuta reflexa stem and Corchorus olitorius seed treated mice is due to the suppressed ovarian steroidogenesis.

3-Hydroxysteroid Dehydrogenases↗
PubMed2003

Bobble-head doll syndrome: some atypical features with a new lesion and review of the literature.

Bobble-head doll syndrome is a rare and unique movement disorder encountered in children. It is characterized by continuous or episodic involuntary forward and backward and side to side movement of the head at the frequency of 2-3 Hz. Neuroimaging in most of the cases reveals third ventricular tumors, suprasellar arachnoid cysts, aqueductal stenosis and other lesions in the region of the third ventricle along with communicating hydrocephalus. In most of the circumstances, the problem starts in the first decade of life and diversion of cerebrospinal fluid by shunt operation is very often accompanied by dramatic improvement. We report one case where bobbing of the head started at around 12 years of age. Additionally, there was evidence of partial left abducens nerve palsy, tremor in the outstretched hands, difficulty in finger-nose test and tandem walking, hyperreflexia and extensor plantar response. He was unconscious on two occasions and there was evidence of gross hydrocephalus along with a thin membranous web, running transversely across the lower part of the aqueduct of Sylvius without any cerebrospinal fluid flow void. Ventriculo-peritoneal shunt abolished the abnormal movements. We propose that the aqueductal web was the offending agent for the pathogenesis of bobble-head doll syndrome in our case and this lesion has not been identified in the cases reported so far. Relevant literature in this regard has also been reviewed.

Adolescent↗
PubMed2003

Evaluation of anti-inflammatory activity of Vernonia cinerea Less. extract in rats.

The methanol extract of the whole plant of Vernonia cinerea Less. was evaluated for its anti-inflammatory activity in acute (carrageenin, histamine and serotonin induced rat paw edema) and a chronic model (cotton pouch induced granuloma). The methanol extract (250 and 500 mg/kg(-1) p.o.) exhibited significant activity (p < 0.001) against all phlogistic agents used in a dose dependant manner. In the chronic model (cotton pouch granuloma method) the methanol extract exhibited significant anti-inflammatory activity. All these effects were compared with standard drug phenylbutazone (100 mg/kg(-1) p.o.).

Animals↗
PubMed2003

The structure of the pineal complex in a common Indian teleost, Catla catla: evidence for pineal-induced inhibition of testicular function within an annual reproductive cycle.

The structure of the pineal complex and the annual reproductive cycle in a major Indian carp, Catla catla, were investigated in the present study. Additionally, given the well-known inhibitory effects of the pineal on reproductive function in mammals, attempts were made to investigate whether or not the pineal exerts an inhibitory influence on reproductive function in this piscine species as well. Sexually adult animals were utilized in all experiments. The cytomorphology of the pineal complex and a number of parameters for testicular function--such as testicular cytology, serum testosterone levels, and testicular activities of two steroidogenic enzymes, 17beta-hydroxysteroid dehydrogenase (17beta-HSD) and delta5-3beta-hydroxysteroid dehydrogenase (delta5-3beta-HSD) were examined over a period of two years. Our studies showed that the pineal complex in this species consists of three separate but distinctly connected components: (a) an end vesicle (EV); (b) a long pineal stalk (PS); and (c) a dorsal sac (DS). Of these, the epithelial lining of the EV consists of cells that have rounded vesicular nuclei and long apical cytoplasmic processes that reach the lumen, features suggestive of photoreceptor cells. The cells of the PS have some similarity with those of the EV, while DS cells appear columnar and ciliated. With regard to gonadal activity, germ cell profiles revealed that this species has four distinct phases during the annual reproductive cycle: (a) preparatory (January-April); (b) pre-spawning (May-June); (c) spawning (July); and (d) post-spawning (August-December). During the spawning phase (July), seminiferous tubular diameter, percentage of late spermatids within seminiferous tubules, and serum testosterone levels showed the highest values compared to those obtained in most of the other phases of the reproductive cycle. Also in July, along with peak serum testosterone levels, the activities of 17beta-HSD and delta5-3beta-HSD were at their highest levels. In a correlation between the pineal cytology and testicular functional status, it was noted that both the nuclear diameter and the apical cytoplasmic projections of the EV photoreceptor cells showed a significant reduction, thus suggesting a reduced synthetic activity, during the month of July, the spawning phase of the reproductive cycle. In contrast, the same features of the EV cells during the other phases of the reproductive cycle showed an increased cellular and metabolic activity--a time when the gonads were less active and in a quiescent stage. These data suggest an inhibitory role of the pineal on gonadal function and thus provide additional credence to the concept that, as in higher mammals, there exists an inverse relationship between the pineal activity and gonadal function in teleost fishes as well.

Analysis of Variance↗
PubMed2003

The morpho-anatomy and histology of the pineal complex in a major Indian carp, Catla catla: identification of the pineal photoreceptor cells and their responsiveness to constant light and constant darkness during different phases of the annual reproductive cycle.

In contrast to mammals in which the pineal gland is a discrete structure situated dorsally in the brain, the "pineal gland" in teleost fishes is composed of a number of separate but connected constituent parts, collectively described as the "pineal complex." In this paper, we have described the pineal complex in a common Indian carp, Catla catla, which exhibits an annual reproductive cycle. Attempts have been made to (a) provide an in-depth description of the structure of the pineal complex; and (b) identify the photoreceptor cells of the pineal, by exposing the animals to constant light (LL) and constant darkness (DD). Furthermore, we examined any possible influence of the reproductive status of the fish on the responsiveness of the pineal photoreceptor cells in C. catla following exposure to LL and DD. To this end, a total of four experiments were carried out during the four different phases of the annual reproductive cycle that is characteristic of this species. Each of these four experiments was carried out for a period of 30 days after which the fishes were sacrificed, different parts of the pineal complex were dissected out, and processed for histological and karyometric studies. Our results showed that the pineal complex in this species is composed of three separate but connected parts, (a) an end vesicle (EV); (b) a dorsal sac (DS); and (c) a long and thin pineal stalk (PS) that attaches the EV to the DS. Detailed karyometric and histo-morphologic studies following exposure of the animals to DD and LL showed that constant darkness led to a stimulatory effect on the pineal photoreceptor cells of the EV as evident from a significant increase in the nuclear diameter. In contrast, the nuclear diameter of the photoreceptor cells in animals subjected to constant light showed a significant reduction. Furthermore, the observed cellular changes in the EV of fish exposed either to LL or DD were independent of the stage of the gonadal cycle. The apparent lack of any cellular responses either in the PS, or in the DS, following exposure to LL and DD, suggests that in C. catla the photoreceptor cells are located only within the epithelial lining of the EV and that these cells respond in a manner similar to mammalian pinealocytes when subjected to comparable photoperiod-induced experimental conditions.

Animals↗
PubMed2003

Evaluation of formalin-acetone sedimentation in the concentration of stool for intestinal parasites.

Formalin-acetone sedimentation was compared with the formalin-ether method for the concentration of stool for intestinal parasites. Of 80 stool specimens, 45 (56.25%) were positive for parasites by the formalin-acetone method. The figures for the two methods were formalin-ether 35 (43.75%) and for the direct lacto-phenol cotton blue wet mount method 17 (21.25%). There was no statistically significant difference in the parasite recovery rate between the two methods. Acetone is more stable, safer, and a cheaper fat solvent and promises to be a useful alternative to ether.

Acetone↗
PubMed2003

Orthostatic tremor: report of a case and review of the literature.

Orthostatic tremor is a rare movement disorder characterized by tremulousness of the lower limbs on standing that disappears on walking, sitting or on lying down and a distinctive electromyographic burst of 14 to 16 Hz. On inspection, fine ripples can sometimes be seen over the quadriceps on standing. The tremor has a tendency to reappear even in the supine posture if the lower limb muscles are put to an isometric contraction state, indicating thereby that in spite of the fact that the tremor occurs on standing, it is essentially 'orthostasis independent' and the central factor is the contraction of the muscles. As a matter of fact, the tremor is abolished if the subject is suspended by harness, thus relieving him of muscle contraction. Doubts are being cast whether it is a variant of essential tremor since a number of families are being reported to be suffering from this disease as well. Positron emission tomography reveals hyperactivity of cerebellum in orthostatic tremor as it shows in essential tremor, therefore lending credence to such a hypothesis. However, lack of response to alcohol, propranolol and primidone in orthostatic tremor stands out as a serious challenge to such a view. Lack of positive family history, synchrony of contracting group of muscles and negative 'resetting' of the tremor by increasing peripheral load-phenomena consistently observed in orthostatic tremor and not in essential tremor, are other features that often help to distinguish between the two conditions. We report a case of orthostatic tremor that presented with the classical clinical and electromyographic features. Relevant literature in this regard is also being reviewed.

Aged↗
PubMed2003

Co-infection with hepatitis C virus and human immunodeficiency virus among patients with sexually transmitted diseases in Pondicherry, South India.

Hepatitis C virus (HCV), which is usually transmitted by blood and blood products is emerging as an important agent in the list of sexually transmitted diseases (STDs). The present study was undertaken to document the burden of HCV infection in individuals with STDs in this tertiary care hospital in South India. One hundred serum samples collected from individuals with STDs were tested for antibodies to HCV by a third generation ELISA. All the samples were also screened for HIV infection. Six out of 100 individuals were found to possess antibodies against HCV (95% confidence interval [CI=1.3-10.7%). Fourteen out of 100 samples were positive for HIV (95% CI=7-20.9%). The seroprevalence of HCV in HIV positive individuals was 21.4% (3/14) whereas the corresponding figure for HIV negative individuals was only 3.5% (3/86). The difference was found to be statistically significant (p<0.01).

Adolescent↗
PubMed2003

Diagnostic evaluation of extrapulmonary tuberculosis by fine needle aspiraton (FNA) supplemented with AFB smear and culture.

One hundred forty-three patients, 72 males and 71 females, with extrapulmonary tuberculosis were aspirated and subjected to cytological (Ziehl-Neelsen stain) examination and culture in Lowenstein-Jensen media. Routine haematological examination and Mantoux test were done in all the cases, x-ray chest in 112, skeletal x-ray in 3 relevant cases and sputum was examined for AFB in 16 cases where pulmonary tuberculosis was associated/suspected with extrapulmonary tuberculosis. HIV status was evaluated in 51 cases and 9 (7.64%) were seropositive. FNA cytology in 102 cases (71.3%) had caseating epithelioid granulomas while smear for AFB was positive in 57 cases (39.8%). Both culture and smear were positive in 29 (20.2%) cases. Combining both smear and culture yielded positive results in 47.5% cases. It was observed that AFB positivity was higher in untreated patients and with HIV positive cases. Further more, the triad of FNAC, AFB smear and culture were cheaper, foolproof and confirmatory than costlier tests like TB IgG, IgM, RTPCR and BACTEC.

Adolescent↗
PubMed2003

A case of disseminated hydatidosis.

A young lady initially found to have hydatid cysts in the lung only, subsequently within a very short period was found to develop cysts in the liver. Soon after, she developed cysts in the subcutaneous tissue over the anterolateral chest wall, which, on investigation, revealed hepatic cysts herniating through the chest wall defects caused by previous operations. The unique features of this case include the degree of dissemination, the multiplicity of sites and the peculiar nature of herniation of the hepatic cysts into the parietes.

Adult↗