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V Kumar

Publications and source records attributed to V Kumar.

At least 397 records · Page 22Linked to original sources
PubMed1994

Expression of the S-locus receptor kinase multigene family in Brassica oleracea.

The S-receptor kinase (SRK) gene which is implicated in the self-incompatibility system of Brassica oleracea is one member of a large and complex family of similar sequences. Genomic and cDNA clones were isolated for the authentic, S-linked SRK29 gene and its DNA sequence determined. Reverse transcriptase PCR (RT-PCR) was used to detect the expression of SRK29 and other members of the family in stigma, leaf and root tissues. The SRK was found to be stigma-specific whereas, for instance, K3 transcripts appeared in all three tissues. The RT-PCR analysis also demonstrated the existence of partially processed intermediates for several of the kinase transcripts and, in the case of SRK29, a product apparently resulting from the splicing of a cryptic intron. RFLP analysis of an F2 family segregating for the S29 allele was used to show S-linkage for the SRK and possibly for the K2 sequence. The K8 kinase probe also revealed a minor RFLP which segregated with the S-locus.

Amino Acid Sequence↗
PubMed1994

Cloning and characterization of ERF-1, a human member of the Tis11 family of early-response genes.

Members of the Tis11 family of early-response genes are characterized by a high degree of sequence similarity around a putative zinc finger motif. They are induced by a variety of cell agonists and polypeptide mitogens, including 12-O-tetradecanoylphorbol-13-acetate (TPA) and epidermal growth factor (EGF). We describe the cloning and sequencing of a human member of this gene family, EGF-response factor 1 (ERF-1), the homolog of the mouse Tis11b/rat cMG1 genes. The human and rodent genes are similar, with 5' UTR, coding sequence, and 3' UTR highly conserved. The promoter/enhancer region and intron sequences contain multiple putative transcription factor binding motifs characteristic of early-response genes. Amino acid sequence comparison of the seven members of the Tis11 family cloned so far identifies a repeated consensus motif of (x+)YKTELC(x+)x5GxCxYGx(x+)CxFxH involving the potential zinc finger. Toward the carboxyterminal end is a region with a high percentage of prolines (15/73) and, partially overlapping, a serine-rich domain (20/54). These may be important as trans-activation and phosphorylation sites. The 3' untranslated region is unusually long, extending over 1,860 bp. The sequence immediately downstream from the translational stop codon has extensive secondary structure potential. The 3' UTR is 60% AT rich, but contains two GC rich (> 70%) regions. In addition there are multiple reiterations of a destabilization sequence, as well as a single UUAUUUAU motif characteristic of mRNAs specifying proteins involved in the inflammatory response. The mRNA contains a consensus polyadenylation signal.

Amino Acid Sequence↗
PubMed1994

Natural killer cells recognize common antigenic motifs shared by H-2Dd, H-2Ld and possibly H-2Dr molecules expressed on bone marrow cells.

Murine natural killer (NK) cells can mediate specific rejection of bone marrow cell (BMC) allografts. Whereas positive recognition of allogeneic MHC antigens forms the basis for T cell alloreactivity, it has been postulated that NK cells are reactive against targets that do not express certain self-encoded MHC class I antigens. Here, we study the immunogenicity of BMC grafts from two class I transgenic mice, D8 (B6 mice with an H-2Dd transgene) and C3H.Ld (C3H mice with an H-2Ld transgene). D8 BMC grafts are acutely rejected by B6 but not D8 recipients. This suggests that antigenic motifs associated with the H-2Dd molecule are recognized. B6 mice depleted of their CD3+ but not NK1.1+ cells can still reject D8 BMC grafts. These data suggest that NK1.1+/CD3- cells recognize the H-2Dd derived antigenic motifs. Similarly, C3H.Ld BMC grafts are rejected by B6 x C3H F1 but not B6 x C3H.Ld F1 recipients. Thus, antigenic motifs associated with the H-2Ld molecule can also be recognized. Furthermore, expression of either H-2Dd or H-2Ld by the recipients renders them unable to reject D8 or C3H.Ld BMC grafts. Therefore, H-2Dd and H-2Ld molecules appear to express common antigenic motifs recognized by NK cells. Additional studies with B6.R4 (KbIbSbDr), an intra-H-2 recombinant mouse, indicated that a third class I molecule, possibly H-2Dr, also shared the common antigenic motifs with both H-2Dd and H-2Ld molecules. Thus, positive recognition of class I antigens by NK cells can occur. However, expression of some of these antigenic motifs appear to be negatively controlled by certain H-2r genes as suggested by rejection of D8 and B6.R4 BMC grafts by D8 x B10.RIII F1 and B6.R4 x B10.RIII F1 hybrids respectively.

Animals↗
PubMed1994

Case report: idiopathic hypoparathyroidism co-existing with celiac disease: immunologic studies.

Idiopathic hypoparathyroidism (IH) is often an isolated disorder in adults, but in children it is usually a component of the autoimmune polyendocrinopathy syndrome. The authors describe a patient diagnosed with isolated IH at age 57 and celiac disease at age 64. Testing of patients' serum show antibodies of the immunoglobulin A isotype against endomysium, reticulin, and gliadin antigens, as well as immunoglobulin G against gliadin. The circulating immunoglobulins reacted with bovine parathyroid tissue, specifically smooth muscle of the blood vessels and glandular cells, as detected by indirect immunofluorescence. Testing of celiac disease positive sera showed similar parathyroid reactivity. When the patient was placed on a gluten-free diet, endomysial, reticulin, and gliadin antibodies decreased to undetectable levels, which was parallel with disappearance of the parathyroid immunoreactivity. The gluten-free diet also produced severe hypercalcemia that responded to calcitriol withdrawal, and ultimately required a reduction by half of the original calcitriol dose. It is possible that in this case the same antibody or antibodies may have caused both hypoparathyroidism and celiac disease. We conclude that, as in the case of childhood-onset IH variants, patients with late-onset isolated IH should be monitored for additional endocrine and extra-endocrine autoimmune disorders.

Celiac Disease↗
PubMed1994

Changes in body water compartments in children with acute meningitis.

Changes in body water and electrolytes were studied in 30 children, 2 months to 5 years old, with acute meningitis. Total body water (TBW), extracellular water (ECW) and urinary and serum sodium and osmolality were estimated on the day of hospitalization (Day 1) and after recovery/Day 10. Thirty age- and sex-matched children served as their controls. The TBW (683 +/- 63 (mean +/- SD) ml/kg) as well as ECW (311 +/- 76 ml/kg) was significantly higher in children with meningitis on Day 1 than in the controls (TBW 642 +/- 49 ml/kg, ECW 271 +/- 62 ml/kg) (P < 0.01), whereas the values after recovery (TBW 643 +/- 48 ml/kg, ECW 272 +/- 63 ml/kg) were similar to those of controls. Thus on the average a child with acute meningitis had excess body water, all of which was in the ECW compartment. The mean ECW excess was 33 +/- 32 ml/kg. Twenty-four of 27 surviving children had higher TBW and ECW at the time of admission compared with the values after recovery. On multiple regression analysis, the only significant determinant of ECW excess was severity of the illness (partial r2 = 0.62). The ECW excess was 70 +/- 8 ml/kg in severely ill, 50 +/- 32 ml/kg in moderately ill and only 12 +/- 18 ml/kg in mildly ill children (P < 0.01). Those who had complications or sequelae had much higher ECW (49 +/- 26 ml/kg) than those who recovered completely (17 +/- 27 ml/kg).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1994

Immunological diagnosis of childhood coeliac disease: comparison between antigliadin, antireticulin and antiendomysial antibodies.

The immunological markers proposed to supplement intestinal biopsy for the diagnosis of coeliac disease are antigliadin, antireticulin and antiendomysial antibodies. These antibodies have been studied separately or compared as pairs, but no prospective comparison of all three antibodies in childhood coeliac disease exists. Thirty-four confirmed coeliacs were compared with nine non-coeliacs with pathological small intestines, and 32 children with a normal intestinal histology. Sera were examined for IgG- and IgA-antigliadin antibodies (AGA) by ELISA, and for IgA-antireticulin antibodies (ARA) and IgA endomysial antibodies (EMA) by indirect immunofluorescence. In active coeliac disease, IgA-EMA was the most sensitive (97%), while IgA-AGA the least sensitive antibody (52%). The specificity of IgA-AGA, IgG-AGA, IgA-ARA, IgA-EMA was 95%, 92%, 100% and 98%, respectively. Positive predicted values of ARA and EMA were comparable (97-100%), while EMA had the highest negative predicted value (98%). Compared with IgG-AGA, IgA-EMA titres better reflected variations in dietary gluten, and correlated best with intestinal pathology. Compared with AGA and ARA sensitivity, specificity and predictive values, EMA is the most reliable serological marker for the diagnosis of coeliac disease. It reflects dietary changes in gluten and correlates best with intestinal histopathology. Therefore, it should be considered the best of the three serological tests available for childhood coeliac disease.

Adolescent↗
PubMed1994

A cytoskeletal actin gene in the mosquito Anopheles gambiae.

Five actin genes have been identified in the mosquito Anopheles gambiae, and a constitutively expressed actin gene has been chosen for detailed analysis. We have physically mapped and sequenced this gene and six associated cDNAs, including translated coding regions, as well as the 5' and 3' flanking sequences. Analysis of stage-specific RNA shows this gene to be present in all stages of mosquito development and in an established A. gambiae cell line, thus indicating a cytoskeletal actin. In the sequence of the translated coding region and in pattern of expression, this gene is very similar to the cytoskeletal actin genes of Drosophila melanogaster, and in sequence, equally similar to the Artemia cytoskeletal actin gene 403 (99.2% identity among the three amino acid sequences). Sequencing of this A. gambiae actin gene (designated act1D for its location in chromosome division 1D) and selected cDNAs shows that it possesses three alternative leader sequences; thus the gene appears to have three alternative promoters. These promoters should ultimately prove useful in the production of transgenic constructs for constitutive expression.

Actins↗
PubMed1994

A technique for nucleic acid in situ hybridization to polytene chromosomes of mosquitoes in the Anopheles gambiae complex.

A sensitive, simple, and reproducible in situ hybridization technique for the detection and precise localization of specific nucleic acid sequences on chromosomes of members of the Anopheles gambiae complex is described. Modifications of the in situ hybridization technique are described that allow simultaneous hybridization of several probes with the chromosomes on a single slide and the multiple use of a single chromosome preparation for several different probes hybridized successively on the same slide. Examples are shown that illustrate the utility of the technique for localization of both single copy and repeated sequences in both polytenized euchromatin and centromeric heterochromatin.

Animals↗
PubMed1994

Expression of CZ-1: a CD45RB epitope on progenitors of natural killer and other haematopoietic cells.

CZ-1 is a novel sialic acid-dependent epitope of the murine CD45RB molecule which is expressed on cells that proliferate when cultured in IL-2. Because IL-2 appears to be important in the differentiation of NK cells, the authors examined the expression of CZ-1 on immature NK-lineage cells within the bone marrow. All mature NK1.1+ cells as well as their NK1.1- IL-2 responsive precursors were CZ-1+. Furthermore, IL-2 unresponsive transplantable NK progenitor cells expressed CZ-1 also. To examine expression of CZ-1 on other immature lymphoid progenitor cells, CZ-1+ and CZ-1- marrow cells were transplanted into lightly irradiated scid mice. Transfer of CZ-1+ cells resulted in rapid and sustained generation of thymocytes and splenic B cells, whereas CZ-1- cells caused delayed repopulation. This suggested that the slowly repopulating pluripotent stem cells lacked CZ-1. Therefore, expression of CZ-1 on Ly6+ Lin- c-kit+ cells, highly enriched for pluripotent stem cells, was examined. This population appeared to be homogeneously CZ-1dull. Thus, it appears that expression of CZ-1 is developmentally regulated, with differentiation associated with increased expression. Since CZ-1 is expressed on a protein tyrosine phosphatase, it is likely that this molecule regulates differentiation of NK and other lymphoid cells.

Animals↗
PubMed1994

Generation of reactive oxygen intermediates in relation to short course chemotherapy in children suffering from pulmonary tuberculosis.

Functional status of phagocytes in relation to 6 months' short course chemotherapy of tuberculosis was studied with special reference to antigen-5 (Ag-5) of Mycobacterium tuberculosis. Phagocytic capacity and overall generation of reactive oxygen intermediates (ROI) measured as chemiluminescence (CL) response was studied in peripheral blood monocytes obtained from 20 children with pulmonary tuberculosis (PTb) and was compared with 20, age and sex matched, controls. In untreated children the CL response (mean +/- SD) with latex (0.90 +/- 0.08) and Ag-5 (0.99 +/- 0.11) was found to be severely depressed compared with controls (Latex, 19.2 +/- 5.10; Ag-5, 48.12 +/- 7.10). A significant improvement was seen in response to both the stimulants (Latex, 15.20 +/- 1.50; Ag-5, 28.15 +/- 7.32) after 3 months of therapy and became equal to, or slightly higher than, the values obtained with controls by the end of therapy. This study suggests that newly diagnosed untreated PTb is associated with an in vitro antigen specific compromise of phagocytic capacity and oxidative metabolic burst activity that is gradually and progressively corrected during the course of effective short course chemotherapy. In addition, Ag-5 is a potent stimulator of monocytes/macrophages; its potency being far greater than latex.

Adjuvants, Immunologic↗
PubMed1994

A study of four major areas in out patient department of NIMS with special reference to patient satisfaction.

A study of patient satisfaction was undertaken in four major Out-patient Departments of General Medicine, Cardiology, Orthopaedics and Neurology which accounts for nearly 70-80% of the Out-patient visits. The study was conducted through distribution of structured questionnaire for a period of six months with a total sample of 300 questions. Keeping in view the working hours, registration pattern, waiting time of various services, the work load and the patient's satisfaction for various services were studied. Some bottlenecks such as lack of flow concept and lack of adequate floor space were identified. Appropriate statistical tests (Chrisquare) were applied in assessing the patient's satisfaction and appropriate recommendations were made accordingly.

Humans↗
PubMed1994

Predictors of serious bacterial infection in infants up to 8 weeks of age.

During a period of 2 years we prospectively studied 116 infants up to 8 weeks of age with suspected sepsis. Each infant was assessed clinically before laboratory evaluation for sepsis. Depending upon impression of sepsis, temperature abnormality, micro ESR (mESR), WBC counts and toxic granulations infants were assigned to either high (n = 74) or low (n = 31) risk group for serious bacterial infection (SBI). All infants were kept under observation till the final decision for hospitalization was made. Eighty six per cent of cases in high risk group and 26% of cases in low risk group were hospitalized and treated with antibiotics. SBI was present in 55% of the high risk group infants compared to one (3%) in the low risk group. Culture for bacterial infections were positive in 22 (19%) cases; bacteremia was found in 15 (13%) infants. None of the variables individually predicted the presence of bacteremia or SBI satisfactorily. Presence of two or more criteria out of the three criteria namely impression of sepsis, raised mESR and toxic granulation could identify 93% of infants with bacteremia and 95% of those with SBI and excluded 89% of cases without SBI.

Escherichia coli↗
PubMed1994

An epidemiological study of congenital malformations in rural children.

Children between 0-6 years of age from six villages of Ambala District were screened for congenital malformations. Of 1371 children, malformations were observed in 30 (prevalence 22/1000). Twenty children had major malformations and six had multiple anomalies. Cardiovascular malformations were the commonest (37%) followed by musculoskeletal (30%), gastrointestinal (23%), central nervous system (13%) and genitourinary anomalies (6.6%). An etiological factor (maternal rubella infection or drug exposure during early pregnancy) could be ascertained in only 3 cases. Traditional birth attendents (TBA) and Anganwadi workers (AWW) were helpful in identifying 95% of the cases with externally visible malformations in rural areas. In majority of cases no remedial measures were taken by the parents.

Adult↗
PubMed1994

Breast feeding pattern in neonates.

The present study comprised 100 mothers of newborn babies with regard to their belief and practices about lactation. A vast majority (98.2%) of the mothers were breast feeding, 87.9% mothers used prelacteal feeds of one sort or the other. Only 0.5% breast fed their babies within 6 hours and nearly 50% started after 48 hours. Colostrum was discarded by 82.9% of mother and nearly 73% wanted to continue breast feeding beyond 1 year. The age of weaning preferred was after 1 year by 91%. Only 24.7% mothers had undergone antenatal check ups. Hence, much needs to be done with regards to proper antenatal care and advice to discourage wrong and harmful feeding practices.

Attitude↗
PubMed1994

Effect of mercuric chloride and cadmium chloride on gonadal function and its regulation in sexually mature common carp Cyprinus carpio.

Gonadal function in fish, Cyprinus carpio was significantly affected by sublethal doses of mercuric chloride (HgCl2) and cadmium chloride (CdCl2) in chronic (45 days) exposure. Parameters investigated were nonesterified (NE) and esterified (E) cholesterol of ovary, liver and serum and ovarian 3 beta-Hydroxysteroid and 17 beta-Hydroxysteroid dehydrogenase enzyme activity and serum and pituitary gonadotropin (GtH) levels. Both the pollutants were able to reduce the hypothalamic extract (HE) or gonadotropin releasing hormone (GnRH) induced pituitary GtH release in vitro. Short term (96h) exposure of the fish to the pollutants had no significant effect on the gonadal function. In addition to the deleterious effect of pollutants on the gonadal steroidogenesis and pituitary gonadotropin release, using [4-14C] cholesterol as a tracer it was found that for 45 days exposure, HgCl2 had an adverse effect on the transport of cholesterol from circulation to ovary.

Animals↗