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G Das

Publications and source records attributed to G Das.

At least 19 recordsLinked to original sources
PubMed2006

Coexistent partial anodontia and supernumerary tooth in the mandibular arch: a rare case.

Coexistent partial anodontia and supernumerary tooth in the lower jaw is a very uncommon condition. Very few cases have been reported in the literature of this condition, etiology of which is still obscure. Presented here is a rare case of simultaneous presence of single supernumerary tooth together with missing permanent central incisor teeth in the lower jaw without any associated systemic condition or syndrome.

Anodontia↗
PubMed2005

Evidence for a role of initiation factor 3 in recycling of ribosomal complexes stalled on mRNAs in Escherichia coli.

Specific interactions between ribosome recycling factor (RRF) and elongation factor-G (EFG) mediate disassembly of post-termination ribosomal complexes for new rounds of initiation. The interactions between RRF and EFG are also important in peptidyl-tRNA release from stalled pre-termination complexes. Unlike the post-termination complexes (harboring deacylated tRNA), the pre-termination complexes (harboring peptidyl-tRNA) are not recycled by RRF and EFG in vitro, suggesting participation of additional factor(s) in the process. Using a combination of biochemical and genetic approaches, we show that, (i) Inclusion of IF3 with RRF and EFG results in recycling of the pre-termination complexes; (ii) IF3 overexpression in Escherichia coli LJ14 rescues its temperature sensitive phenotype for RRF; (iii) Transduction of infC135 (which encodes a functionally compromised IF3) in E.coli LJ14 generates a 'synthetic severe' phenotype; (iv) The infC135 and frr1 (containing an insertion in the RRF gene promoter) alleles synergistically rescue a temperature sensitive mutation in peptidyl-tRNA hydrolase in E.coli; and (v) IF3 facilitates ribosome recycling by Thermus thermophilus RRF and E.coli EFG in vivo and in vitro. These lines of evidence clearly demonstrate the physiological importance of IF3 in the overall mechanism of ribosome recycling in E.coli.

Alleles↗
PubMed2005

Hypovitaminosis D among healthy adolescent girls attending an inner city school.

AIMS: To determine the prevalence of hypovitaminosis D among healthy adolescent schoolgirls attending an inner city multiethnic girls' school. METHODS: Fifty one (28%) of 182 girls (14 white, 37 non-white; median age 15.3 years, range 14.7-16.6) took part in the study. Biochemical parameters, dietary vitamin D intake, muscle function parameters, duration of daily sunlight exposure (SE), and percentage of body surface area exposed (%BSA) were measured. RESULTS: Thirty seven (73%) girls were vitamin D deficient (25-hydroxyvitamin D (25OHD) <30 nmol/l) and 9 (17%) were severely deficient (25OHD <12.5 nmol/l). The median (range) 25OHD concentration of white girls (37.3 nmol/l (18.3-73.3)) was higher than that of non-white girls (14.8 nmol/l (5.8-42.8)). The median (range) concentration of parathyroid hormone in white girls (2.8 pmol/l (1.0-3.7)) was lower than that of non-white girls (3.4 pmol/l (1.7-34.2)). Serum Ca, inorganic phosphate, alkaline phosphatase, and 1,25-dihydroxyvitamin D were not different in white and non-white girls. For the whole group, 25OHD concentration was related to the estimated SE and %BSA, but not to estimated intake of vitamin D. In white girls, the estimated SE and %BSA were significantly higher than that of non-white girls. The median times taken to complete the Gower's manoeuvre and grip strength were not different in the two groups; these variables were not related to serum 25OHD. CONCLUSIONS: Hypovitaminosis D is common among healthy adolescent girls; non-white girls are more severely deficient. Reduced sunshine exposure rather than diet explains the difference in vitamin D status of white and non-white girls.

Adolescent↗
PubMed2005

Assessment of duration of immunity in crossbred cattle immunized with glycoproteins isolated from Hyalomma anatolicum anatolicum and Boophilus microplus.

To develop immunoprophylactic measures against multi-tick infestation, two glycoproteins of 34 and 29 kDa were isolated from the larvae of Hyalomma anatolicum anatolicum and Boophilus microplus, respectively, and assessed for their efficacy against experimental challenge infestations. The synergistic effect of the antigens in the presence of incomplete Freund's adjuvant was found to confer protection (DT%) in animals against 56.48% of larvae and 52% of adults of H. a. anatolicum, while the effect was 40% against adults of B. microplus. The efficacy (E%) of the antigens in combination against larvae and adults of H. a. anatolicum was calculated as 70% and 64.3%, respectively, and 63% against adults of B. microplus. A direct correlation between anti-glycoprotein antibody response and protection against infestation was observed. Western blot analysis detected specific antigen in the sera of animals of group A. The antigens in combination with incomplete Freund's adjuvant could protect animals from H. a. anatolicum and B. microplus infestations for at least 30 weeks. The possibility of employing the vaccination strategy in Indian conditions is discussed.

Animals↗
PubMed2005

Reduction of Theileria annulata infection in ticks fed on calves immunized with purified larval antigens of Hyalomma anatolicum anatolicum.

Larval antigen of Hyalonmma anatolicum anatolicum, the vector of Theileria annulata, was purified by two-step affinity chromatography using anti-tick gut-specific rabbit IgG and IgG from immunized cattle. The purified antigen showed the presence of a single polypeptide of 37 kDa (GHLAgP) on SDS-PAGE. Two groups (I and II) of naive crossbred calves (Bos taurus x B. indicus) were immunized with I mg of GHLAgP in three divided doses. Immunized calves of group I were also infected with a sublethal dose of T annulata along with a group of non-immunized calves (group III). Animals in groups I, II, III as well a control group (group IV) were challenged with live nymphs of H. a. anatolicum on the 10th day of immunization. There was a significant reduction in the number of emerging adults of 56.9% +/- 1.67%, in calves of group I (p < 0.01) and 63.09% +/- 1.26% in calves of group II (p < 0.001) compared to the controls. The calves of groups I and II showed antibody responses to tick antigen up to day 70 post immunization. Infection with T. annulata was determined in the salivary glands of adult ticks that developed from the nymphs used for challenge infection. In ticks taken from group I calves, there was a 75.0% +/- 0.00% infection compared with only 85.0 +/- 2.88% infection in ticks taken from calves of group III. Using PCR, a lower infection (83.33% +/- 3.33%) was detected in ticks that developed from calves of group I compared with calves from group III (90.00% +/- 2.88%). The ground-up tick supernatants (GUTS) of the ticks taken from calves of group III yielded higher infection rate and exhibited higher infectivity titre in in vitro infection assay of bovine mononuclear cells than the GUTS of the ticks taken from calves of group I. The results suggest a partial reduction in growth rate of T. annulata in ticks feeding on calves immunized with GHLAgP.

Animals↗
PubMed2005

Assessment of contraceptive services in a maternity unit of a district general hospital in the UK.

A survey was undertaken to assess the quality of contraceptive services provided to women delivering in a District General Hospital. Separate questionnaires were given to the women and the midwives giving the contraceptive advice. Response rate of the survey was 87%. Thirty eight per cent of women reported having some discussion on contraception during antenatal period. All the women had received contraceptive advises during the postpartum period. Eighty one per cent of women felt that sufficient information and enough time was given to discuss contraception. However analysis of questionnaires indicated that most received information only on short-term contraceptive methods. Out of 64 midwives surveyed, 52 had attended a family planning course. However 37 of them had attended the course at least 3 years earlier. Thirty eight midwives felt that they have adequate knowledge to give advice but all of them reported that they should receive further training. There should be provision for comprehensive discussion regarding contraceptive options during both antenatal and postpartum periods. Midwives require regular training in family planning.

Contraception↗
PubMed2005

Erupted maxillary conical mesiodens in deciduous dentition in a Bengali girl--a case report.

Mesiodens is a midline supernumerary tooth commonly seen in the maxillary arch. It is the most significant dental anomaly affecting permanent dentition mainly and primary dentition rarely. It may occur as an isolated dental anomalous condition or may be associated with a syndrome. Many theories have been promulgated to explain its etiology. But an exact etiology is still obscure. Incidence of mesiodens in children varies from 0.15 to 3.8%. Boys are affected more (2:1) than girls. Morphologically, mesiodens may be of three types: the most commonly seen is conical, while tuberculate and supplementary types.

Child, Preschool↗
PubMed2002

Assessment, diagnosis and management of lower urinary tract symptoms in men.

Lower urinary tract symptoms are very common and the approach to assessment and management has changed dramatically over the past few years. Previously referred to as prostatism, benign prostatic hyperplasia and bladder outflow obstruction, it is now recognised that in most men symptoms are due to a combination of benign prostatic enlargement and age-related bladder dysfunction. Most men require only simple tests for a diagnosis, with the more complex investigations reserved for when the diagnosis is not clear. Symptom bothersomeness and effect on quality of life are the critical factors when deciding how to treat a man. A cascade of treatments exists, including conservative management, medical therapy and surgery. A man moves up the cascade when the present management strategy fails to control symptoms. Traditional surgical techniques such as transurethral resection of the prostate are still appropriate for some men, although with improved medical treatments available the number of men undergoing surgery is declining.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2001

The source of early IFN-gamma that plays a role in Th1 priming.

When naive CD4 T cells are primed, they rapidly differentiate into polarized Th1 and/or Th2 phenotypes. A major factor in producing such polarization is the early production of cytokines (IL-12 and IFN-gamma in the case of Th1 cells and IL-4 in the case of Th2 cells). One issue that remains unresolved is the source of the early IFN-gamma that synergizes with IL-12 to fully polarize CD4 T cells into Th1 cells. We have examined this question by injecting mice with anti-CD3 and examining cells from normal and various MHC-knockout mice. We found that IFN-gamma is induced rapidly in a small subset of CD8 T cells. This subset is absent in mice that lack beta2-microglobulin, but not in K(b)D(b)-double-knockout mice, indicating that these CD8 T cells are dependent on nonclassical MHC class Ib molecules. The early burst of IFN-gamma polarizes CD4 T cells toward Th1 cells, in part by stimulating the release of IL-12 from APC. We also use TAP- and CD1-knockout mice to show that such cells are not CD1-restricted NK T cells, nor are they dependent on TAP-1 transport for surface expression of the relevant MHC class Ib molecule. Therefore, they arise on MHC class Ib molecules that do not depend on TAP-1 transporters.

Animals↗
PubMed2001

Topological diversity of artificial beta-barrels in water.

Rigid-rod beta-barrels are composed of interdigitating, short, amphiphilic peptide strands flanked by stabilizing rigid-rod "staves". We here report studies on the topological diversity of these recently devised artificial beta-barrels with regard to their length. For this purpose, homologous p-octiphenyl, p-sexiphenyl, and p-quarterphenyl rods were equipped with complementary tripeptide strands based on the sequences Lys-Leu-Lys and Glu-Leu-Glu. The stability of rigid-rod beta-barrels of different length was determined by denaturation with guanidinium chloride. Free energies of delta GH2O = -5.2 kcalmol-1, delta GH2O = -2.9 kcalmol-1, and delta GH2O < -0.3 kcalmol-1 found for homologous p-octiphenyl, p-sexiphenyl, and p-quarterphenyl beta-barrels demonstrated strong dependence of beta-barrel stability on beta-barrel length. These results revealed a very qualitative minimal (approximately 23 A) and an "ideal" beta-barrel length (approximately 34 A), synergistic formation (alpha = 1.4) and remarkable stability for "ideal" p-octiphenyl beta-barrels exceeding that of several proteins and most synthetic models. Rigid-rod beta-barrels with p-oligophenyl "staves" longer than approximately 34 A will be very difficult to make and study because of rapidly decreasing rod solubilities. However, a strategy to bypass this apparent upper limitation of beta-barrel length is introduced: supramolecular matching of mismatched rods yielded elongated beta-barrels (61 A) of acceptable stability (delta GH2O = 2.2 - 3.1 kcalmol-1).

Protein Conformation↗
PubMed2001

Neutrophil collagenase (MMP-8) is expressed during early development in neural crest cells as well as in adult melanoma cells.

Matrix metalloproteinase-8 (MMP-8) is a neutral metalloproteinase of the fibrillar collagenase family that also includes MMP-1 and MMP-13. In contrast to the other collagenases, MMP-8 has a very limited tissue distribution, thought to be restricted to neutrophils and chondrocytes. In a previous study, we observed MMP-8 expression in human melanoma cells. This observation led us to assess in more detail the expression of MMP-8 in normal and malignant melanocytic cells. We found that MMP-8 was expressed by 11 out of 12 human melanoma cell lines tested and all 10 primary melanomas we examined, but was not expressed by four primary neonatal melanocyte strains. Since melanocytes arise from highly motile neural crest cells, we examined the hypothesis that MMP-8 might be expressed by neural crest cells. RT-PCR analysis of post-implantation mouse embryos indicated the presence of MMP-8 transcripts at E9.5. In situ hybridization and immunohistochemistry of mouse embryos between E9.5-E14.5 demonstrated MMP-8 expression in the surface ectoderm, neural crest cells and chondrocytes. MMP-8 was also detected in neural crest cell migration located in the circumference of the neural tube, branchial arches and the notochord. In addition, MMP-8 expression was observed between the somites, in circumscriptive areas of the developing brain, heart, and eye, and in the interdigital zones of the limbs. In summary, we found MMP-8 to be the first fibrillar collagenase expressed during development. In contrast to its restricted tissue expression post-partum, MMP-8 was present in multiple embryonic tissues, including neural crest cells. The production of MMP-8 by migrating neural crest cells may contribute to their ability to degrade fibrillar collagen matrices while in transit.

Adult↗
PubMed2001

Immunoprotective efficacy of a purified 39 kDa nymphal antigen of Hyalomma anatolicum anatolicum.

Soluble nymphal antigens (HNAg) were purified by immunoaffinity chromatography using CNBr-activated Sepharose 4B coupled with immunoglobulin ligands from animals immunized with HNAg and 69-71% protected against challenge infestations, and 8% recovery of the purified protein (Aff-HNAg) was obtained. Following immunization of crossbred calves (Bos indicus x Bos taurus) with 1600 sg of Aff-HNAg in three divided doses, significant rejections of larvae (p<0.001, 84.2%), nymphs (p<0.05, 61.4%) and adults (p<0.05, 58.7%) were recorded. No significant changes were recorded in the engorgement weights of the larvae and nymphs, but there was a significant (p<0.05) reduction in the weight of the engorged adults. Immunization conferred a significant decrease in the numbers of resultant nymphs (p<0.001) and adults (p<0.001) that had fed on the immunized animals. SDS-PAGE analysis identified a 39 kDa protein, previously isolated from larvae of Hyalomma anatolicum anatolicum, as the antigen responsible for the induction of resistance against all the stages of the tick.

Animals↗
PubMed2001

Another novel use of endoscopic clipping: to anchor an esophageal endoprosthesis.

Endoscopic Hemoclips were developed as a method of securing permanent hemostasis in cases of nonvariceal gastrointestinal bleeding. However, Hemoclips have also been found useful in several other situations, such as closure of small perforations, as marking devices, and for anchoring feeding tubes. We describe here a further novel use of Hemoclips--to anchor an esophageal endoprosthesis.

Aged↗
PubMed2001

An unusual cause of renal impairment: a latex glove.

Male genital self-mutilation is thought to be increasing in incidence and is underreported in the literature. We therefore have no clear and uniform treatment programmes. We present a case of genital self-mutilation involving a 16-year-old male. The case highlights an important complication and the multidisciplinary approach to its management.

Adolescent↗
PubMed2000

Qa-2-dependent selection of CD8alpha/alpha T cell receptor alpha/beta(+) cells in murine intestinal intraepithelial lymphocytes.

Murine intestinal intraepithelial lymphocytes (iIELs) are made up of a heterogeneous mix of T cells with unique phenotypes. Whereas CD8(+) T cells in peripheral lymphoid organs use CD8alpha/beta and are selected on MHC class Ia molecules, a majority of iIELs use CD8alpha/alpha. Here, we report that the presence of CD8alpha/alpha TCR-alpha/beta cells in iIELs is independent of classical MHC class I molecules K(b) and D(b), as illustrated by their presence in K(b)/D(b) double-knockout mice and in mice lacking a nonclassical MHC class I molecule, CD1d. Most strikingly, their presence is decreased by approximately 70% in mice lacking transporter associated with antigen processing (TAP). The TAP-dependent nonclassical MHC class I molecule Qa-2 is strongly implicated in the presence of these cells, as inferred from the low numbers of CD8alpha/alpha TCR-alpha/beta T cells in mice deficient in Qa-2 genes. Second, a Qa-2-transgenic mouse made in a Qa-2(-) strain showed an increase in the numbers of CD8alpha/alpha cells among its iIELs. Thus, the presence of CD8alpha/alpha TCR-alpha/beta cells in iIELs is mainly dependent on the nonclassical MHC class I molecule Qa-2.

Animals↗
PubMed2000

The NK-2 homeobox gene scarecrow (scro) is expressed in pharynx, ventral nerve cord and brain of Drosophila embryos.

Members of the NK homeobox family have been widely conserved during evolution. Here we describe the sequence and expression of a novel Drosophila NK-2 homeobox gene, named scarecrow (scro), which shows considerable homology to vertebrate Nkx-2.1. During embryogenesis, scro expression is initially observed in the pharyngeal primordia and later maintained in the pharynx. During band germ retraction, scro expression appears in two bilateral clusters of procephalic neuroblasts that give rise to distinct neuronal clusters in the brain. In addition, scro expression is observed in segmental clusters of neuronal precursors in the ventral nerve cord. In larval stages, scro expression occurs in portions of the optic lobe regions. These observations indicate that scro and vertebrate Nkx2.1 share similarities both in terms of their sequence and their expression patterns.

Amino Acid Sequence↗
PubMed2000

Efficacy of lactulose in cirrhotic patients with subclinical hepatic encephalopathy.

To investigate the role of lactulose in the treatment of cirrhotic patients with subclinical hepatic encephalopathy (SHE), 40 cirrhotic patients, 33 males and 7 females, were included in the study. The diagnosis of SHE was made by quantitative psychometric tests including the number connection test (NCT), figure connection test (FCT) parts A and B, and two performance subtests of Wechsler adult intelligence scale, ie, picture completion (PC) and block design (BD) tests. SHE was diagnosed in 26 (65%) of 40 patients. Of these 26 patients, 14 patients were randomized to treatment group (lactulose 30-60 ml/day for three months, SHE-L) and 12 patients to no treatment group (no lactulose, SHE-NL). Psychometric tests were repeated in all patients in both groups and in six patients with no SHE (group NSHE, N = 14) after three months. The mean scores and number of the abnormal psychometric tests at entry were significantly higher in patients in groups SHE-L and SHE-NL than in patients in group NSHE; however, there was no significant difference between SHE-L and SHE-NL. The mean number of the abnormal psychometric tests decreased in patients in group SHE-L after three months of treatment with lactulose (2.9 +/- 0.9 vs 0.8 +/- 1.2; P = 0.004); however, there was no change in patients in group SHE-NL after three months (3.7 +/- 1.5 vs 3.5 +/- 1.3; P = NS). While SHE improved in 8 of 10 patients in group SHE-L, none of the patients in group SHE-NL improved after three months of follow-up (P < 0.001). Two patients in group SHE-NL also developed overt encephalopathy during the study period. We conclude that lactulose treatment in cirrhotic patients with SHE is effective.

Adult↗