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R Smith

Publications and source records attributed to R Smith.

At least 1,243 records · Page 69Linked to original sources
PubMed1985

Non-stress antenatal cardiotocography--a prospective blind study.

A prospective blind study of non-stress antenatal cardiotocography was undertaken in a group of 216 'high risk' pregnancies. The 'Cardiff' scores and the outcome of the pregnancies were compared subsequently. Low scores were associated with infants that were small-for-gestational age and fetal distress in labour, while high scores were associated with normal intrauterine growth. Although antepartum cardiotocography is predictive of fetal and neonatal outcome the extent to which its availability will prevent adverse outcome appears limited.

Female↗
PubMed1985

Non-stress antenatal cardiotocography--a prospective randomized clinical trial.

A randomized controlled trial examined the effects of non-stress antepartum cardiotocography on obstetric management and assessed its usefulness as a diagnostic test of fetal compromise. Daily cardiotocograph recordings were made in 396 antenatal patients at increased risk of fetal compromise but were withheld from the clinicians responsible for care in half the cases. The frequency of intrapartum fetal distress and low Apgar score was similar in the two groups. The three normally-formed perinatal deaths all occurred in the revealed group but in only one case could earlier obstetric intervention have altered the outcome. Availability of non-stress cardiotocography was not associated with an increased rate of induction of labour or caesarean section.

Adolescent↗
PubMed1985

Peripartum concentrations of beta endorphin and cortisol and maternal mood states.

Nineteen women were studied before, during and after labour by assessment of their mood using a variety of psychological tests and by measurement of their plasma concentrations of beta-endorphin and cortisol. Beta-endorphin and cortisol concentrations rose markedly during labour and were influenced by the type of analgesia used. A deterioration in cognitive performance between days 2 and 4 postpartum correlated positively with the fall in beta-endorphin concentrations from those in labour to those on the fourth day postpartum. The women were more anxious and depressed at 38 weeks' gestation than on days 1-4 postpartum and the elevation of mood on day 2 postpartum correlated with a measure of depression 8 weeks later. It is postulated that the phenomenon of postpartum blues is a reaction to the euphoria of delivery which in turn is a response to endorphin release during labour. Whilst these changes may have a role in promoting maternal-infant attachment it is at the expense of maternal depression some weeks later.

Anxiety↗
PubMed1985

Adoptive transfer of murine host protection to salmonellosis with T-cell growth factor-dependent, Salmonella-specific T-cell lines.

A spent medium antigen was prepared from the avirulent RIA strain of Salmonella typhimurium. Lymph node cells isolated from female BALB/c mice injected subcutaneously with the spent medium antigen exhibited antigen-specific proliferation. By using these cells and T-cell growth factor, continuous spent medium antigen-specific, Thy 1.2-sensitive lines were generated. These cells exhibited antigen-specific proliferation in vitro and were effective in inducing significant (P less than 0.01) host protection when adoptively transferred to naive syngeneic mice.

Animals↗
PubMed1985

Local passive immunization by monoclonal antibodies against streptococcal antigen I/II in the prevention of dental caries.

Local passive immunization with monoclonal antibodies (Mc Ab) to Streptococcus mutans was attempted as an alternative approach to active systemic immunization. We prepared an immunoglobulin G class Mc Ab to the cell surface protein determinant of streptococcal antigen I/II and applied it repeatedly to the teeth of rhesus monkeys. This resulted in decreased colonization by S. mutans in fissures and smooth surfaces of teeth and no dental caries, unlike the results in control animals, which developed caries and showed a high proportion of S. mutans on their teeth. There was no significant difference in serum, salivary, or gingival fluid antibodies to S. mutans between the two groups of animals. Any objections raised over systemic immunization inducing cross-reactive antibodies are therefore overcome by local passive immunization. The mechanism of prevention of colonization has not been established, but we postulate that the Mc Ab which is directed against an important cell surface antigenic determinant of S. mutans (streptococcal antigen I/II) prevents adherence of S. mutans to the acquired pellicle on the tooth surface. S. mutans reacts with the Mc Ab and becomes opsonized, phagocytosed, and killed by the local gingival traffic of neutrophils.

Animals↗
PubMed1985

Evaluation of a direct immunofluorescence test for diagnosing gonorrhoea.

A new direct immunofluorescence reagent (Syva and Genetic Systems Inc) was evaluated for its ability to detect Neisseria gonorrhoeae in specimens from populations with a high prevalence of the infection. Gonorrhoea was diagnosed by culture in 45 of 105 (43%) urethral specimens from men and 17 of 90 (28%) urethral and 25 of 60 (42%) cervical specimens from women. In men the immunofluorescence test had a sensitivity of 84.4% and a specificity of 100%; Gram staining gave values of 94% and 100%, respectively. The sensitivity of the immunofluorescence test could be increased to 89% by testing duplicate smears. In women the immunofluorescence test had a sensitivity of 65% and a specificity of 98% for urethral samples and values of 72% and 94%, respectively for cervical samples. At both sites the sensitivity of the Gram stain was 40% and the specificity 100%. The testing of duplicate immunofluorescence smears increased the sensitivity to 76% for urethral and 88% for cervical samples.

Cervix Uteri↗
PubMed1985

Exclusion of the alpha 1(II) cartilage collagen gene as the mutant locus in type IA osteogenesis imperfecta.

Using two restriction site polymorphisms within the structural gene coding for human type II collagen we have examined the segregation of this gene in three pedigrees with dominantly inherited osteogenesis imperfecta (Sillence type IA). We have demonstrated that the gene does not segregate with clinical expression of the disease and cannot, therefore, contain the mutation responsible for osteogenesis imperfecta in these families.

Chromosome Mapping↗
PubMed1985

Pericholecystic hepatic activity in cholescintigraphy.

Gallbladder nonvisualization in cholescintigraphy has been shown to be a reliable finding in acute cholecystitis. In some cholescintigrams, we have observed faintly increased pericholecystic hepatic activity in conjunction with gallbladder nonvisualization. To determine the frequency and significance of the pericholecystic hepatic activity finding, we evaluated 334 consecutive adult patients who had cholescintigrams with technetium-99m diisopropylphenylcarboamoyl iminodiacetic acid. Pericholecystic hepatic activity was seen in 21% of the abnormal scans demonstrating gallbladder nonvisualization but in none of the other scans. Thirteen of these patients underwent surgery; 11 (85%) were found to have acute cholecystitis, and two (15%) had chronic cholecystitis. Four patients (31%) had acute gangrenous cholecystitis, and five (39%) had cholecystitis complicated by gallbladder perforation. The pericholecystic hepatic activity sign is not specific for gangrenous cholecystitis or gallbladder perforation but does reliably indicate inflammatory gallbladder disease and is associated with a relatively high incidence of cholecystitis complicated by perforation.

Adolescent↗
PubMed1985

Choroid plexus Na+/K+-activated adenosine triphosphatase and cerebrospinal fluid formation.

The quantitative relationship between intraventricular fluid formation and choroid plexus Na+/K+-activated (transport) adenosine triphosphatase (ATPase) was studied in rabbit and dog by perfusing the ventricular system with a solution containing ouabain (10(-8) to 10(-3) M). The effect of ouabain in the same range of concentrations on ATPase activity was also measured by the release of inorganic orthophosphate from in vitro choroid plexus tissue. Normally, about 20 to 25% of ATPase activity in lateral ventricle plexus is Na+/K+-activated, and this component is almost completely inhibited by ouabain in a concentration of 10(-4) M. At this concentration, the rate of intraventricular cerebrospinal fluid (CSF) formation is decreased some 70 to 80% in dog and rabbit. The results of this study suggest that a portion of the intraventricular fluid formation is insensitive to cardiac glycoside inhibition and that either there are two different mechanisms responsible for choroid plexus fluid formation or there is a significant non-ATPase dependent extrachoroidal source of CSF.

Animals↗
PubMed1985

Liver-spleen scintigraphy in patients with acquired immunodeficiency syndrome.

The liver-spleen scintigrams of eight patients with the acquired immunodeficiency syndrome (AIDS) were reviewed to characterize the abnormal findings and to assess the diagnostic utility of scintigraphy in evaluating these patients for hepatic and splenic disease. Hepatosplenomegaly was present on the scintigrams of six patients. Additional findings included a solitary hepatic defect in a patient with Kaposi sarcoma and liver metastasis, multiple hepatic defects in a patient with multiple hemangiomas, decreased splenic activity in a patient with lymphoma, and markedly diminished splenic activity in a patient with thrombocytopenic purpura. Hepatosplenomegaly is the most common abnormal scintigraphic finding in AIDS patients. However, the presence of other hepatic or splenic parenchymal scintigraphic abnormalities suggests an underlying secondary pathologic process. Liver-spleen scintigraphy can be a reliable and valid adjunct to the diagnosis of occult hepatic or splenic disease in AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Brain specific gravity and CT scan density measurements after human head injury.

White matter specific gravity was measured using the microgravimetric method in 20 comatose patients with diffuse head injury who were undergoing intracranial pressure (ICP) monitoring, and in 19 patients with focal injuries who were undergoing evacuation of contusions or intracerebral hematomas. Computerized tomography (CT) density readings were obtained for each site of white matter sampling by locating the sampling site on the preoperative CT scan. A significant correlation was found between the specific gravity values and the CT density numbers (r = 0.775; p less than 0.001). Patients with focal injuries demonstrated reduced perifocal specific gravity, suggesting brain edema. The mean specific gravity in patients with diffuse injury was within the normal range. In 10 of 12 patients in whom the specific gravity was above the normal range, the CT density was also above the normal range. These data suggest that cerebral vascular engorgement is the cause of the high specific gravity. Six (60%) of this small subgroup of 10 patients also demonstrated a high ICP.

Adult↗
PubMed1985

Polymorphism and tissue distribution of maternally transmitted antigen defined by cytotoxic T lymphocyte lines.

We have developed cytotoxic T lymphocyte (CTL) lines specific for two determinants of the maternally transmitted antigen (Mta) and have used these CTL lines to study the tissue distribution of Mta. In previous reports, we characterized CTL lines specific for the Mta.1 determinant. Here, we describe CTL lines specific for the newly defined Mta.2 determinant. Mta.2-specific CTL lines lysed target cells from F1 mice of an NZB (Mtf beta) mother but did not lyse target cells from reciprocal F1 mice of any Mtf alpha mother. Backcross mice were used as the source of target cells to demonstrate that the Mta.2-specific CTL were H-2 nonrestricted in their recognition. Mta.-1- and Mta.2-specific CTL lines were used to demonstrate Mta expression on lymphoid cells taken from spleen, thymus, lymph nodes, and bone marrow. In addition, Mta was expressed on cultured cell lines of myeloid, epithelial, and mesenchymal origin. Our results suggest that Mta is not a differentiation marker restricted to lymphocyte subpopulations.

Animals↗
PubMed1985

Cellular requirements for the generation of primary cell-mediated lympholysis responses to Qa-1 antigens.

Mixed leukocyte cultures (MLC) between NZB responder spleen cells and Qa-1-disparate stimulator spleen cells were employed to determine the cellular requirements for the generation of primary anti-Qa-1 cell-mediated lympholysis (CML) responses. Although primary anti-Qa-1 cytotoxic lymphocytes (CTL) were generated during H-2-homologous stimulation, anti-Qa-1 CTL were not detectable from MLC in which the stimulators were H-2 allogeneic. Anti-Qa-1 CTL also were not generated from MLC in which the stimulators were semiallogeneic. Thus, H-2 identity between responder and stimulator cells was not sufficient to permit the generation of primary anti-Qa-1 CTL when H-2 disparity was also present. The capacity for H-2 disparity to prevent anti-Qa-1 CML responses was further demonstrated in MLC containing both H-2-allogeneic and H-2-homologous stimulator cells. Therefore, in subsequent studies we employed NZB responders and H-2-homologous, Qa-1-disparate stimulators. When various subpopulations of stimulator cells were studied for their ability to induce anti-Qa-1 CTL, nylon wool-adherent cells were found to be potent stimulators, but nylon wool-nonadherent cells were not. Furthermore, depletion of macrophages from the stimulator population abrogated the generation of anti-Qa-1 CML responses, despite the presence of responder macrophages in the culture. In contrast, all fractionated subpopulations stimulated anti-H-2 CML responses. When macrophage-enriched cells were used as stimulators, anti-Qa-1 CTL could be generated with approximately 80-fold fewer stimulator cells than when unfractionated splenocytes were used as stimulators. These findings indicated that stimulator macrophages were essential for the generation of primary anti-Qa-1 CTL. Direct evidence for macrophage expression of Qa-1-antigens was obtained by using a Qa-1b-specific CTL clone. These studies provide i) the first evidence for Qa-1 expression on macrophages, ii) a basis for comparison of the cellular interactions necessary to generate CTL against H-2K/D-encoded vs Qa-1-encoded class 1 antigens, and iii) a model for investigating the mechanisms responsible for the immunodominance of H-2K/D alloantigens.

Animals↗
PubMed1985

Helper and suppressor functions of human mononuclear cells depleted of antigen-binding T8+ cells.

We have utilized the antigen-binding function of a subset of T8+ cells to remove these cells in vitro from human peripheral blood mononuclear cells. This was carried out by treating the cells with streptococcal antigen (SA), monoclonal anti-SA antibody and complement. The concentration of SA binding to T8+ cells differs with the HLA-DR type of the cells: 1 ng SA binds to DRw6+ cells and elicits T helper activity, whereas 1000 ng SA elicits T suppressor activity, in an assay for antibody-forming cells. After depletion of the antigen-binding cells by the SA-specific complement-dependent killing technique, the helper function of the DRw6+ cells was lost but suppression was elicited not only by 1000 ng but also by 1 ng SA. Similarly, DRw6- cells which bind 1000 ng SA to elicit helper activity and 1 ng to elicit suppression, when depleted of the SA-binding cells, resulted in loss of helper activity but again, suppression could be elicited by both 1000 and 1 ng SA. We suggest that treatment of mononuclear cells with antigen, the specific antibody and complement removes the T8+ antigen-binding cells which present antigen to T helper cells and results in the loss of helper function. Suppressor function is however, not only retained with the original concentration of SA but also expressed with that required to elicit helper function in the untreated cells. These findings are consistent with our hypothesis that the antigen-binding and presenting T8+ cells also function as contrasuppressor cells. Thus, the T8+ subset of cells have a dual function, to present antigen and to activate T helper cell function, and to prevent suppressor cells from inhibiting the helper cells.

Antibodies, Bacterial↗