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Biomedical subjects

R Ganguly

Publications and source records attributed to R Ganguly.

At least 19 recordsLinked to original sources
PubMed1992

Characterization of a Drosophila melanogaster gene similar to the mammalian genes encoding the tyrosine/tryptophan hydroxylase activator and protein kinase C inhibitor proteins.

A cloned 1.3-kb cDNA that hybridizes to genomic clone 549, containing genes predominantly expressed in the head of Drosophila melanogaster, was characterized. DNA sequencing showed that the cDNA-encoded protein is similar to a family of mammalian proteins, called 14-3-3, which activate tyrosine hydroxylase (TyrOHase) and tryptophan hydroxylase (TrpOHase), the two key enzymes regulating biosynthesis of biogenic monoamine neurotransmitters, such as dopamine and serotonin, in the brain. The putative D. melanogaster 14-3-3 protein (D14-3-3) shares 72.4, 74.3 and 78.3% amino acid (aa) sequence identity and 83.5, 87.7 and 85.9% aa sequence similarity with the beta, gamma and eta forms of bovine 14-3-3 protein, respectively. A lower (71%), but significant level of aa sequence identity was also found between D14-3-3 and sheep brain protein kinase C inhibitor protein (KCIP). The D14-3-3 gene expresses 1.0-, 1.9- and 2.9-kb mRNAs which show differential expression patterns. While the 2.9-kb mRNA is expressed only in the head, the other two mRNAs are found both in the head and body. Compared to the 1.9- and 2.9-kb mRNAs, the 1.0-kb mRNA is more abundant in the ovary and is probably maternally inherited. The 1.9-kb mRNA is the most predominant species in the embryos and its level peaks between 6-15 h of embryogenesis. The D14-3-3 gene is predominantly expressed in the ventral nerve cord of the embryo, and in the neural tissues of the head.(ABSTRACT TRUNCATED AT 250 WORDS)

14-3-3 Proteins↗
PubMed1992

The Drosophila G protein gamma subunit gene (D-G gamma 1) produces three developmentally regulated transcripts and is predominantly expressed in the central nervous system.

A genomic clone, 536, located at the 44CD region of polytene chromosomes of Drosophila melanogaster, has been characterized for its neurobiological importance. We found that this clone contains a gene which produces 2.6-, 1.3- and 1.1-kilobase (kb) RNAs. While the 2.6-kb RNA is expressed only in the head, the 1.3-kb RNA is present exclusively in the body. The 1.1-kb RNA, however, is found in both the head and body, but in much higher concentration in the head. DNA sequence analysis of a 2.6-kb RNA-specific cDNA showed that this gene encodes a 70-amino acid polypeptide which is the putative Drosophila homologue to the gamma subunit of the bovine G-protein. The Drosophila protein, named D-G gamma 1, shares 46, 43, and 28% identity, and 59, 52, and 60% similarity, with the gamma 2, gamma 3, and gamma t proteins of bovine G proteins, respectively. Sequencing of the 1.1-kb RNA-specific cDNA clone revealed that the 1.1-kb RNA is produced from the 2.6-kb transcription unit by usage of an alternative polyadenylation site, and has a coding region identical to that of the 2.6-kb RNA. Genomic Southern blot hybridization indicated that the Drosophila genome has only one D-G gamma 1 gene. Throughout development the 1.1-kb RNA is found to be the most prevalent species; its level peaks between 9 and 12 h of embryogenesis. As is the case for the other G protein genes of Drosophila, the D-G gamma 1 gene is predominantly expressed in the central nervous system of the fly.

Amino Acid Sequence↗
PubMed1992

A BamHI repeat element is predominantly associated with the degenerating neo-Y chromosome of Drosophila miranda but absent in the Drosophila melanogaster genome.

In Drosophila miranda, females have two X1 and two evolving X2 chromosomes, and males have one of each of these two X chromosomes and a Y chromosome. In males, the homologue of the X2 chromosome, the neo-Y chromosome, is attached to the Y chromosome and is under the process of degenerative evolution. We have examined a developmentally regulated X2/neo-Y chromosome-linked gene, 549mr, of D. miranda and found that the neo-Y chromosome-linked copy of this gene (549mr-NY) contains an insertional DNA. We discovered that sequences similar to those in the insertional DNA are present in multiple copies in the genome of both sexes of D. miranda but are more abundant in the males. The insertional DNA also identified a 1.1-kilobase BamHI repeat that is present in at least 6-fold excess in the male genome as compared to the female. This BamHI repeat and similar DNA sequences are predominantly concentrated on the evolving neo-Y chromosome, but very few are found on the homologous X2 and other chromosomes. The BamHI repeat also hybridizes with 2.0- and 1.8-kb RNAs and many other RNA species, which together are also approximately 6-fold greater in males. No sequences similar to the BamHI repeat are found in Drosophila melanogaster. Moreover, the BamHI repeat is not homologous to P, copia, or other D. melanogaster transposable elements. This repeat, named the NY element, may be involved in gene disruption and the process of degenerative evolution of the neo-Y chromosome.

Animals↗
PubMed1991

Dosage compensation of a retina-specific gene in Drosophila miranda.

The X1R chromosome of Drosophila miranda and the 3L autosome of Drosophila melanogaster are thought to have originated from the ancestral D chromosomal element and therefore may contain the same set of genes. It is expected that these genes will be dosage compensated in D. miranda because of their X linkage. To test these possibilities and to study evolution of the dosage compensation mechanism, we used the 3L-linked autosomal head-specific gene 507 ml of D. melanogaster to isolate the homologous gene (507mr) from a D. miranda genomic library. In situ hybridization showed that gene 507 is located at the 12A region of the X1R chromosome of D. miranda, indicating that the chromosomal homology deduced by cytogenetic means is correct. Restriction analysis and cross-specific DNA and RNA blot hybridization revealed the presence of extensive restriction pattern polymorphism and lack of sequence similarity in some areas of the 507mr and 507 ml DNA, including the 3' portion of the transcribed region. However, the 5' portion of the transcribed region and the DNA sequences, located approximately 0.8 kb upstream and 3 kb downstream from the 507 ml gene showed a high degree of similarity with the DNA sequences of comparable regions of the 507mr gene. In both species gene 507 codes for a highly abundant 1.8 kb RNA which is expressed in the retina of the compound eye. Although in D. miranda the males have one and the females have two copies of the 507 gene, the steady-state levels of the 507 mRNA in both sexes were found to be similar, indicating that gene 507 is dosage compensated in D. miranda.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol Dehydrogenase↗
PubMed1989

Factors affecting immunization rate in a cohort of elderly veterans: a retrospective pilot study of influenza vaccine compliance.

A survey of aged veterans greater than or equal to 85 years old was undertaken to determine their vaccination behaviour prior to mounting a local education campaign on influenza vaccine. A questionnaire inquiring into circumstances which may have influenced their decision to be immunized against influenza was mailed to all 300 elderly veterans (greater than or equal to 85) obtained from the register at the James A. Haley Veterans' Hospital. Ninety-two persons responded in self addressed stamped envelopes and data were analysed six months following mailing date. The most important reason for not being immunized was lack of information concerning vaccine recommendations and its availability (48%). Fear of 'shots' and side effects was the next most important reason for not taking the vaccine (19%). Amotivation and transportation difficulties played comparatively minimal roles (10%, 13%). These data suggest that health education measures may improve vaccine compliance in the elderly population who suffer from higher death rates and complications from influenza.

Aged↗
PubMed1988

Nucleotide sequence of the Drosophila glucose-6-phosphate dehydrogenase gene and comparison with the homologous human gene.

Glucose-6-phosphate dehydrogenase (G6PD) has a major role in NADPH production and is found in almost all cell types. The structural gene for G6PD is X-linked in Drosophila melanogaster, as it is in most eukaryotic organisms, and due to its ubiquitous expression, it can be considered a typical 'housekeeping' gene. Here we present the complete nucleotide (nt) sequence of G6PD cDNAs as well as the genomic copy of the G6PD gene. The G6PD gene has three introns so that the protein-coding region is divided into four segments. The 5'-end of mature G6PD mRNA is located 289 +/- 1 nt upstream from the start codon. The sequence upstream from the transcription start point is G + T-rich and contains no commonly found transcription regulatory elements, such as a TATA box or GGGCGG sequence. D. melanogaster G6PD is 65% homologous with the human G6PD protein but has no homology with the human sequence for the first 42 amino acid residues. The G6PD gene was shown to be active when transduced to autosomal positions. For each transformant, G6PD activity in both male and female adults was not significantly different, indicating that the transduced gene, unlike the resident G6PD, is not dosage-compensated in males.

Amino Acid Sequence↗
PubMed1985

Age interference of lymphokine production by lung derived lymphocytes.

Young adult and aged guinea pigs, 1 and 3 years old respectively, were sensitized intranasally with Bacillus Calmette Guérin (BCG). Lung lavage cells were harvested at 2, 3, 6 and 7 weeks following sensitization and tested for migration inhibitory factor (MIF) production in Mackaness chambers with purified protein derivative (PPD). Oil induced normal pig macrophages were used as indicator cells. Aged guinea pigs, compared to young adult guinea pigs, showed significant delay and reduced levels of MIF production at 2 to 3 weeks. Delayed hypersensitivity skin reaction (DHS) to PPD was also less pronounced at 6 weeks. Senescent immune lung cells were inhibitory to migration of indicator cells in absence of PPD.

Aging↗
PubMed1985

Macrophage functions in aging: effects of vitamin C deficiency.

Groups of young adult and senescent guinea pigs were fed normal and vitamin C deficient diets for 4 weeks and tested for their peritoneal macrophage functions. Serum levels of vitamin C in deficient animals indicated a progressive state of ascorbic acid deficiency and correlated well with the clinical signs and symptoms of scurvy. Fewer macrophages were obtained from the peritoneal cavities of deficient animals and morphologically they were smaller in size. Adverse effects of vitamin C deficiency were enhanced in aged animals. Significantly greater number of aged animals died by 4 weeks of deficiency. Deficient senescent animals had greater decline in macrophage random migration and bactericidal capacity. Following phagocytic stimuli, superoxide anion generation also significantly decreased. Data suggest that vitamin C deficiency might affect macrophage functions in the aged more profoundly and could compromise parameters of host defenses effective against microbial infections.

Aging↗
PubMed1979

Influence of virus infection on the leaf protein yield.

Influence of cowpea mosaic virus (CPMV) and common bean mosaic virus (CBMV) infection on the yield of extractable leaf protein of cowpea cvs. Pusa Phaguni, Pusa Barsati, and Yard Long was studied. An increase as well as decrease in the yield of leaf protein concentrate (LPC), due to virus infection, has been observed. CPMV infection increased LPC yield in all the cowpea cvs., but CBMV decreased it in cys. Pusa Phaguni and Yard Long. Variation in percentage of extractable nitrogen and protein in LPC was also notices. However, total N and protein in leaf and LPC were increased due to virus infection, but total sugar and starch decreased.

Carbohydrates↗
PubMed1979

Glucocorticoid modulation of casein gene transcription in mouse mammary gland.

The influence of cortisol and prolactin on casein gene expression in the mammary gland of lactating BALB/c mice was measured by using a specific cDNA probe to 15S casein mRNA (cDNAcsn). Casein mRNA (mRNAcsn) level in the mammary gland was decreased by 85% 5 days after adrenal ablation, but then was increased 4.4-fold 12 hr after a single injection of hydrocortisone-21-acetate. An 80% decrease in serum prolactin level, induced by the prolactin inhibitor 2-bromo-alpha-ergocryptin (CB-154), did not alter the level of mRNAcsn in the gland. Specific transcription of the casein gene in nuclei isolated from lactating mammary glands was measured by cDNAcsn hybridization to the in vitro synthesized Hg-CTP-containing RNA (Hg-RNA), which was purified by SH-agarose chromatography. The level of the mRNAcsn in Hg-RNA synthesized in the isolated nuclei was 0.09% and this was decreased 85% by alpha-amanitin, indicating that the mRNAcsn sequences in the Hg-RNA were the products of RNA polymerase II-directed DNA-dependent RNA synthesis. Transcription of the mRNAcsn in isolated nuclei was decreased by 70% 5 days after adrenalectomy and a single injection of the glucocorticoid then increased the transcription level 2-fold at 6 hr. Essentially no alteration of the level of transcription was detectable in mammary nuclei isolated from lactating mice with 80% decreased serum prolactin level, induced by CB-154 treatment. The results thus demonstrate a glucocorticoid involvement on the modulation of casein gene expression at the transcriptional level of control.

Adrenalectomy↗
PubMed1979

Lack of effect of an interferon inducer, N,N-dihexadecyl-m-xylylenediamine, on rhinovirus challenge in humans.

CP-28,888-27 and placebo nasal sprays were compared in 62 normal volunteers challenged with rhinovirus type 13 or 21 in two randomized, double-blind studies. Half of the subjects received CP-28,888-27 and half received nasal placebo administered at 24, 20, and 16 h before challenge and 4 and 8 h after challenge. In each study, the number of subjects shedding virus in nasal washes, the number developing fourfold or greater serum antibody responses, and the number developing afebrile or febrile upper respiratory tract illness were not significantly different comparing subjects given CP-28,888-27 and those given placebo. Interferon was detected in nasal washes from 5 of 15 volunteers tested in the CP-28,888-27 group compared to 2 of 15 volunteers from the placebo group.

Adult↗
PubMed1979

Guinea pig lung lavage cells after intranasal BCG sensitization.

Recent studies have suggested that intranasal administration of antigen can induce local cell-mediated immunity in lung lavage cells. The present study was designed to examine the changes in composition of lung lavage cells and their capacity to produce the lymphokine migration inhibitory factor after intranasal immunization with BCG in guinea pigs. Results indicate that guinea pigs responded to respiratory tract BCG infection with an increase in immunocompetent cells in the bronchoalveolar tract and with production of migration inhibitory factor. After local pulmonary BCG administration, the total number of cells increased as compared with that of the uninfected animals, the increase being statistically significant within 2 weeks. This marked increase in the total cell population is due to a more than doubling of the number of macrophages in the lavage fluid. Animals also developed at this time positive delayed hypersensitivity to intradermally administered purified protein derivative. A significant increase in the total lymphoid cells and macrophage population was observed again at 6 weeks after sensitization, suggesting that the response is biphasic in nature. At 6 weeks, however, there was also a significant rise in total lymphocytes and T cell population in addition to macrophage numbers. This increase in T cells correlated with an increase in production of migration inhibitory factor in the presence of purified protein derivative. These data suggest that the immune response of the respiratory tract after BCG challenge involves increased recruitment of immunocompetent cells locally at the site of infection and that these cells are capable of producing effector molecules in terms of the elaboration of migration inhibitory factor.

Animals↗
PubMed1978

Studies on oral adjuvants against murine salmonellosis.

1) Attempts were made to develop oral adjuvants against murine salmonellosis. 2) Streptomycin, levamisole and PHA show potential immunoenhancing properties against salmonella infection. 3) The mode of action of these agents remain to be elucidated. Observed results of PHA enhancement may be related to its blastogenic effects in the splenic T-cells. 4) Decrease in certain bacterial flora resulting in less antigenic competition may be the mode of action of streptomycin as adjuvant when added to oral salmonella vaccine.

Adjuvants, Immunologic↗