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Biomedical subjects

A Roy

Publications and source records attributed to A Roy.

At least 307 records · Page 17Linked to original sources
PubMed1990

CSF neuropeptide Y in alcoholics and normal controls.

Neuropeptide Y is found in brain tissue. In dogs it has been shown to enhance activation of the hypothalamic-pituitary-adrenal axis by corticotropin-releasing hormone. It is localized in certain catecholamine neurons and to some extent colocalized with somatostatin. Disturbances of the central noradrenergic system may underlie some forms of alcoholism. Therefore, we compared male alcoholics and normal controls on cerebrospinal fluid (CSF) levels of neuropeptide Y. There was no significant difference between the two groups for neuropeptide Y. There was also no significant difference for CSF levels of growth hormone releasing hormone. However, there were significant positive correlations between CSF levels of neuropeptide Y and CSF levels of corticotropin-releasing hormone, somatostatin, and growth hormone releasing hormone.

Adult↗
PubMed1990

CSF diazepam-binding inhibitor in alcoholics and normal controls.

Diazepam-binding-inhibitor (DBI) and gamma-aminobutyric acid (GABA) are colocalized in neurons in the brain. This system has been implicated in anxiety and in the regulation of corticotropin-releasing hormone (CRH) secretion. Alcohol has direct and indirect effects on the functioning of GABAA receptors. Abstinent alcoholics are, on the average, more anxious than controls. In tests of animal behavior, DBI has anxiogenic, and alcohol has anxiolytic potency. Therefore, we compared alcoholic patients and healthy controls for cerebrospinal fluid (CSF) levels of DBI, and looked for a correlation between CSF levels of DBI and CRH. There was no significant difference in CSF concentrations of DBI between the two groups and no significant correlation between CSF DBI and our measure of anxiety. However, there was a significant positive correlation between CSF levels of DBI and CRH in both the alcoholic and control groups.

Adult↗
PubMed1990

Hypothalamic-pituitary-adrenal axis dysregulation among diabetic outpatients.

We compared insulin-requiring diabetic outpatients (n = 49) with normal controls (n = 42) for indices of hypothalamic-pituitary-adrenal (HPA) axis activity. Diabetic patients showed significantly elevated 9 a.m. plasma levels of cortisol as well as significantly elevated plasma levels of cortisol and adrenocorticotropic hormone (ACTH) at both 4 p.m. before and 4 p.m. after dexamethasone. Also, there was a significant correlation between postdexamethasone plasma levels of ACTH and duration of diabetes. These results suggest that HPA-axis dysregulation is found among diabetic outpatients. The possible psychiatric implications are discussed.

Adrenocorticotropic Hormone↗
PubMed1990

Cerebrospinal fluid levels of somatostatin, corticotropin-releasing hormone and corticotropin in alcoholism.

Reduced brain and cerebrospinal fluid (CSF) levels of somatostatin, corticotropin-releasing hormone (CRH) and corticotropin (ACTH) have been reported among neuropsychiatric patients with cognitive dysfunction. Alcoholism is a disorder in which associated neuropsychiatric disorders occur. Therefore, we compared CSF levels of somatostatin, CRH and ACTH in alcoholics (n = 100) and normal controls (n = 30). There were no significant differences between the groups in concentrations of the 3 peptides. Moreover, there were no significant correlations between concentrations of the peptides in CSF and computed tomographic measures of the size of brain ventricles. There were, however, significant correlations between CSF concentrations of CRH and ACTH and between CSF concentrations of CRH and somatostatin in both the alcoholic and control groups.

Adrenocorticotropic Hormone↗
PubMed1990

Cerebrospinal fluid monoamine metabolites in alcoholic patients who attempt suicide.

Reduced cerebrospinal fluid (CSF) levels of the serotonin metabolite 5-hydroxyindoleacetic acid have been reported to be commonly associated with suicidal behaviour. Alcoholics are known to often manifest suicidal behaviour. Therefore, we compared cerebrospinal fluid levels of monoamine metabolites in alcoholics who had (n = 20) and had not (n = 108) attempted suicide and healthy volunteers (n = 30). There were no significant differences among the 3 groups for CSF levels of either 5-hydroxyindoleacetic acid, the dopamine metabolite homovanillic acid, norepinephrine, or the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol.

Adult↗
PubMed1990

cis- and trans-acting regulatory elements of the yeast URA3 promoter.

Expression of the yeast pyrimidine biosynthetic gene, URA3, is induced three- to fivefold in response to uracil starvation, and this regulation is mediated by the transcriptional activator PPR1 (pyrimidine pathway regulator 1). In this study, we have analyzed the regulatory elements of the URA3 promoter by DNase I footprinting, using partially purified yeast cell extracts, by deletion mutagenesis, and by 5'-end mapping of RNA transcripts. Two DNA-binding activities have been detected, and at least four distinct cis-acting regions have been identified. A region rich in poly(dA-dT) serves as an upstream promoter element necessary for the basal level of URA3 expression. A 16-base-pair sequence with dyad symmetry acts acts as a uracil-controlled upstream activating site (UASURA) and shows a specific binding only with cell extracts from strains overproducing PPR1. This in vitro binding does not require dihydroorotic acid, the physiological inducer of URA3. The TATA region appears to be composed of two functionally distinct (constitutive and regulatory) elements. Two G + A-rich regions surrounding this TATA box bind an unidentified factor called GA-binding factor. The 5' copy, GA1, is involved in PPR1 induction and overlaps the constitutive TATA region. The 3' region, GA2, is necessary for maximal expression. Neither of these GA sequences acts as a UAS in a CYC1-lacZ context. The promoters of the unlinked but coordinately regulated URA1 and URA4 genes contain highly conserved copies of the UASURA sequence, which prompted us to investigate the effects of many point mutations within this UASURA sequence on PPR1-dependent binding. In this way, we have identified the most important residues of this binding site and found that a nonsymmetrical change of these bases is sufficient to prevent the specific binding and to suppress the UASURA activity in vivo. In addition, we showed that UASURA contains a constitutive activating element which can stimulate transcription from a heterologous promoter independently of dihydroorotic acid and PPR1.

Base Sequence↗
PubMed1990

CSF gamma-aminobutyric acid in alcoholics and control subjects.

Alcohol has widespread effects on the gamma-aminobutyric acid (GABA) system in the brain. This system in the brain is also postulated to have a role in anxiety, and alcoholics have been reported to have more anxiety disorders. Therefore, the authors undertook a study to compare CSF levels of GABA in abstinent alcoholic patients and normal control subjects. There was no significant difference between groups in CSF levels of GABA. Also, there was no significant difference in GABA level between alcoholic patients with histories of withdrawal seizures and those without such a history.

Adult↗
PubMed1990

Plasma norepinephrine in chronic schizophrenia.

Several lines of evidence indicate altered noradrenergic function in schizophrenia. The authors examined resting, standing, and change (standing minus resting) in plasma norepinephrine levels in 14 drug-free patients with chronic schizophrenia or schizoaffective disorder and in 33 age- and sex-matched healthy volunteers. Schizophrenic patients had significantly higher resting and standing plasma norepinephrine levels and significantly greater change. Resting and standing levels were significantly related to positive and negative symptoms. There was a significant positive correlation between resting plasma and CSF norepinephrine levels and a significant negative correlation between CSF homovanillic acid and resting, standing, and change in plasma norepinephrine levels.

Adult↗
PubMed1990

Characteristics of alcoholics who attempt suicide.

Of 298 alcoholic subjects studied by the authors, 19% (N = 57) had attempted suicide. Compared with nonattempters, suicide attempters were significantly more likely to be female, to have a lower socioeconomic status, to be younger, to have begun heavy drinking and experienced the onset of alcohol-related problems at an earlier age, to consume a greater amount of alcohol when drinking, and to have additional lifetime psychiatric diagnoses of major depression, antisocial personality disorder, substance abuse, panic disorder, phobic disorder, or generalized anxiety disorder. Also, significantly more attempters had first- or second-degree relatives who abused alcohol.

Adult↗
PubMed1990

Atlantoaxial instability in Down syndrome--guidelines for screening and detection.

A community survey was conducted in all adults with Down syndrome living in three health districts to see if there was any correlation between radiological and neurological abnormalities which could indicate the presence of atlantoaxial instability. There was no difference in the proportion of individuals with neurological abnormalities in the group with radiological abnormalities suggestive of atlantoaxial instability (6/14) compared with individuals with normal X-rays (50/123) as determined by the chi square test (0.01463: not significant). The clinical and ethical implications for screening of people with Down syndrome living in the community are discussed in view of these findings.

Adult↗
PubMed1990

Assessment in congenital talipes equinovarus.

We have examined the intra- and interobserver repeatability of several measurements of the original deformity and the postoperative correction in children with congenital talipes equinovarus deformity. A neonatal photograph and a preoperative soft tissue radiograph had acceptable repeatability as a method of early assessment. The postoperative range of movement measured by goniometer was adequate for one examiner, (mean: 2-6 degrees), but poor between examiners (mean: 5-14 degrees). Postoperative radiographic measurement between observers was more repeatable than the range of movement. The combined talocalcaneal angle had good repeatability in young children.

Child↗
PubMed1990

Cytogenetic studies in human populations exposed to gas leak at Bhopal, India.

Frequencies of chromosomal abnormalities, sister chromatid exchanges, and replicative index were assessed following peripheral lymphocyte culture in 129 individuals from Bhopal, India. Of these, 83 persons (40 male and 43 female) had been exposed directly to the methyl isocyanate (MIC) gas after the accident at the Union Carbide plant on December 2 and 3, 1984. The remaining 46 samples were taken from age-matched unexposed persons in the same city. Chromosome aberrations were recorded at first cycle metaphase (M1) and sister chromatid exchanges, at second cycle metaphase (M2), following standard schedule. The frequency of chromosomal aberrations was, in general, higher in individuals from the exposed populations, with the females showing a higher incidence. Nondisjunction of chromosomes or laggard was rare. The frequencies of sister chromatid exchanges and depression in mitotic and replicative indices could not be related to exposure or sex. The persistence of chromosomal abnormalities in the form of replicating minutes and exchange configurations, even 1114 days after exposure to the gas, may indicate a residual effect on T-cell precursors.

Accidents, Occupational↗
PubMed1990

[Coronary artery bypass with bovine internal mammary artery graft].

Ten of 1,025 patients undergoing coronary bypass surgery received one or two bovine internal mammary artery grafts. Surgery consisted in quadruple coronary bypass in 1 case, triple coronary bypass in 3 cases and double coronary bypass in 6 cases using 4 autologous saphenous vein grafts, 6 autologous internal mammary artery grafts and 13 bovine internal mammary artery grafts. It was necessary to use bovine internal mammary artery grafts because of total bilateral venous stripping in 5 patients, diffuse, bilateral varicose veins in 4 patients and because of the insufficient length of the vein in 1 patient. Short and medium-term (12 months) angiographic studies of the bovine grafts showed 5 occluded grafts, 2 proximal graft stenoses, and 1 patient graft up to the time of his death of extracardiac causes, with a maximum follow-up of 13 months. One of these 10 patients died in the early postoperative period of extracardiac causes with a patent bovine coronary graft. Another patient died in the 5th postoperative month during reoperation motivated by occlusion of the two implanted bovine coronary grafts. The other 8 patients are alive and stable from the coronary view point. Bovine internal mammary artery grafts may be used to manage an acute episode of coronary insufficiency by providing the time for the collateral circulation to develop but it does not provide a complete and durable method of revascularisation. Their use should therefore be reserved for exceptional cases.

Aged↗
PubMed1990

Studies on non-steroidal anti-inflammatory and related biological activities of 5-(indan-1'-yl)tetrazoles and their intermediates.

Anti-inflammatory, analgesic and anti-pyretic activities of three new 5-(Indan-1'-yl)tetrazoles and anti-inflammatory activity of corresponding carboxamides were compared to those of standard drugs, phenylbutazone and aspirin. The results indicated 5-(Indan-1'-yl)tetrazole as the most promising compound in chronic anti-inflammatory and anti-pyretic tests.

Animals↗
PubMed1990

[Coronary artery bypass using bovine internal mammary artery].

Among 760 patients who underwent coronary artery bypass graft (CABG) 8 received one or two bovine internal mammary artery grafts. The surgical procedures were 4, 3 and 3 CABG respectively in 1, 3 and 4 cases with greater saphenous veins in 4 cases, internal mammary artery in 4 cases and bovine internal mammary artery in 11 cases. The 3 mm bioflow grafts were used to revascularize the left coronary artery in 6 cases (to the left anterior descending, circumflex artery) and the right coronary artery in 5 cases. The indications for the use of bovine mammary artery grafts were lack of suitable autologous vessels because of bilateral saphenous vein stripping in 4 cases, bilateral varicose veins in 3 cases and inadequate length of vein in 1 case. Post-operative angiographic studies of these bovine mammary grafts with a maximum follow-up of 11 months showed 5 occluded grafts, 2 grafts with proximal stenosis, one graft which remained patent until the patient died and 3 grafts still under evaluation. Bovine internal mammary artery grafts provide a solution for the acute stage of coronary disease, but do not achieve total and durable revascularization. Their use must remain exceptional.

Aged↗
PubMed1990

Immunologic and survival studies in mice immunised with cryodestroyed ascites fibrosarcoma (AFS) cells.

Adult mice weighing 20 g, divided into 5 groups, were immunised with single and three cycle cryodestroyed ascites fibrosarcoma cells using different modes of immunisation with respect to dose and administration frequency. Survival against subsequent challenge with the same tumour cells and immune response given by leucocyte migration inhibition, were studied in these animals. It appears from the present study that animals with relatively low antigenic load have a significantly (P less than 0.001) high mean survival time and/or survival index compared with controls than those with relatively high antigenic load. Survival in animals immunised with three cycle cryodestroyed tumour cells is significantly (P less than 0.001) higher than that with single cycle even in face of a greater challenging tumour dose with mode of immunisation remaining the same. Preliminary observations on percentage leucocyte migration inhibition showed that there exists no difference in percentage inhibition with either viable or cryodestroyed tumour cell antigens added to migration chamber excepting in animals immunized with three cycle cryodestroyed tumour cells where percentage inhibition was significantly (P less than 0.001) greater with viable than with cryodestroyed tumour cell antigen without altering the percentage inhibition between the two groups. Factors maximising immune response and their modulating effects are discussed.

Animals↗