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C Smith

Publications and source records attributed to C Smith.

At least 631 records · Page 35Linked to original sources
PubMed1992

Subgingival temperature (III). Relation to microbial counts.

The present investigation examined the relationship of selected bacterial species and subgingival temperature. 35 subjects were measured at 6 sites per tooth for clinical parameters and subgingival temperature. Measurements were repeated for 21 subjects at 2 month intervals providing a total of 66 subjects visits. At each visit, subgingival plaque samples were taken from the mesial aspect of each tooth and anaerobically dispersed, diluted and plated on non-selective media. After anaerobic incubation, colonies were lifted to nylon filters and specific species detected using digoxigenin-labeled whole chromosomal DNA probes. Species enumerated were; A. actinomycetemcomitans serotypes a and b, B. forsythus, B. gingivalis, B. intermedius I and II, C. ochracea, F. nucleatum ss. vincentii, P. micros, S. intermedius, S. sanguis I and II, V. parvula and W. recta. Total viable counts and counts of Capnocytophaga sp. were determined directly from the primary isolation plates. A total of 1581 samples were evaluated. Subject visits with higher mean subgingival temperatures had significantly higher mean %s of B. intermedius I and P. micros, and lower mean %s of Capnocytophaga sp. Sites with higher subgingival temperatures had elevated proportions of B. intermedius I and II, A. actinomycetemcomitans serotype a and B. gingivalis more frequently than sites with lower temperatures, while Capnocytophaga sp. were elevated more often at cooler sites. 43 of the subject visits had follow up attachment level measurements at 2 months. The 1026 microbial samples and the subgingival temperature measurements from these visits were related to longitudinal attachment change.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Non-Hodgkin lymphoma of the gastrointestinal tract.

The gastrointestinal tract is the most commonly involved extranodal site of lymphoma. Primary gastrointestinal lymphoma must be recognized, characterized, and staged accurately, since, in some areas of the bowel, prognosis and therapy vary substantially when compared with those for other neoplasms, especially carcinoma. Radiologic studies, particularly barium studies of the bowel and computed tomography, may be crucial and only noninvasive modalities to use for the evaluation of gastrointestinal lymphoma. Symptoms are nonspecific and may be present for years before a diagnosis is established. Histologic appearance consists of a dense accumulation of lymphocytic tumor cells in a uniform pattern. Gastrointestinal lymphoma produces a spectrum of pathologic and radiologic appearances. Management of the condition may be accomplished with surgical resection, tumor debulking, or palliation. The advantages of postoperative radiation therapy and chemotherapy are not clear. Primary gastrointestinal lymphoma is encountered often enough to warrant familiarity with the clinical, radiologic, and therapeutic options.

Gastrointestinal Neoplasms↗
PubMed1992

Neurotransmitter-induced hypothalamic-pituitary-adrenal axis responsiveness is defective in inflammatory disease-susceptible Lewis rats: in vivo and in vitro studies suggesting globally defective hypothalamic secretion of corticotropin-releasing hormone.

The susceptibility of female Lewis (LEW/N) rats to the development of streptococcal cell wall (SCW)-induced arthritis and other autoimmune phenomena is associated with the inability of their hypothalamic-pituitary-adrenal (HPA) axis to adequately respond to inflammatory stimuli. In contrast, resistance to the development of SCW-induced arthritis and other inflammatory autoimmune manifestations in histocompatible female Fischer rats (F344/N) is related to their intact HPA axis response to inflammatory mediators. To evaluate the mechanism and the specificity of the HPA axis defect in LEW/N rats, we examined the ability of three major excitatory neurotransmitter systems to activate the HPA axis in both Lewis and Fisher rats. The responsiveness of plasma ACTH and corticosterone to the cholinergic muscarinic receptor agonist arecoline, the alpha 1-adrenergic receptor agonist methoxamine and the serotonin (5-HT) type 2 receptor agonist 1-(2,5-dimethoxy-4-iodophenyl)2-aminopropane were significantly blunted and/or abolished in LEW/N compared to F344/N rats. To localize the HPA axis defect to the hypothalamic CRH neuron, we evaluated the ability of explanted hypothalami from the two strains to secrete immunoreactive CRH in vitro, in response to acetylcholine (ACh), norepinephrine (NE), 5-HT and the 5-HT agonist quipazine. LEW/N hypothalami released less immunoreactive CRH (iCRH) in response to ACh, NE, 5-HT and quipazine than F344/N hypothalami. The dose-response curves of these compounds in the former were shifted to the right and/or abolished, suggesting decreased sensitivity of LEW/N hypothalami to these neurotransmitters.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Glands↗
PubMed1992

Spinal muscular atrophy: new thoughts on the pathogenesis and classification schema.

We have established the first prospective, collaborative study of spinal muscular atrophy, the second most common neuromuscular disease of childhood. One hundred and forty-one patients have been evaluated on at least four occasions over a 3-year period. The patients have been grouped by age of onset, as well as by function at the time of initial evaluation. The muscle strength of 96 patients aged 5 years or older was evaluated at 6-month intervals using a fixed myometry system. The new observations made are: (1) The present classification schema is not valid; for example, 49 patients with onset of weakness before 6 months of age (type I or Werdnig-Hoffmann disease), whose life span is said to be only 2 to 4 years, participated in the study and are 4 months to 31 years of age. (2) Thirty-seven patients were evaluated over an 18-month period. None lost strength during this time but four lost function. Although the period of observation was short, the results suggest that the loss of function in patients with spinal muscular atrophy might be explained by a process other than cell death that allows patient strength to be maintained and simultaneously prevents the motor unit from achieving its normal adult potential.

Adolescent↗
PubMed1992

Blunted prolactin responses to d-fenfluramine in sociopathy. Evidence for subsensitivity of central serotonergic function.

Using a neuroendocrine probe we studied nine male offenders in a forensic hospital, convicted of murder, with a diagnosis of antisocial personality disorder, who had been behaviourally 'quiescent' for varying periods and who had not recently been abusing drugs. Nine healthy age-matched men also participated. All subjects received 30 mg d-fenfluramine (d-FEN), a 5-HT releasing agent, orally, after an overnight fast, and serial samples for prolactin estimation were taken hourly for five hours. Responses were significantly impaired in the patients, suggesting a subsensitivity of certain 5-HT systems in antisocial personality disorder, regardless of recent or ongoing behavioural disturbance.

Adult↗
PubMed1992

Dysphagia after botulinum toxin injections for spasmodic torticollis: clinical and radiologic findings.

We prospectively evaluated the frequency, severity, and radiologic features of swallowing abnormalities following Botox treatment of spasmodic torticollis. We performed both clinical and radiologic evaluations of swallowing before and following Botox in 18 consecutive cervical dystonia patients receiving their first Botox treatment. Before Botox, 11% of the patients had clinical symptoms of dysphagia and 22% had radiologic signs of a peristaltic abnormality. After Botox, the signs and symptoms of dysphagia in these patients did not change, but an additional 33% developed new dysphagic symptoms and 50% of the patients developed new peristaltic abnormalities by radiologic studies. Complaints of swallowing difficulty were always associated with abnormal radiologic findings. Neither the total Botox dose nor Botox into particular muscles differed between those with dysphagia and those without.

Adult↗
PubMed1992

Comparison of selection methods at the same level of inbreeding.

Animal geneticists predict higher genetic responses to selection by increasing the accuracy of selection using BLUP with information on relatives. Comparison of different selection methods is usually made with the same total number tested and with the same number of parents and mating structure so as to give some acceptable (low) level of inbreeding. Use of family information by BLUP results in the individuals selected being more closely related, and the levels of inbreeding are increased, thereby breaking the original restriction on inbreeding. An alternative is to compare methods at the same level of inbreeding. This would allow more intense selection (fewer males selected) with the less accurate methods. Stochastic simulation shows that, at the same level of inbreeding, differences between the methods are much smaller than if inbreeding is unrestricted. If low to moderate inbreeding levels are targeted, as in a closed line of limited size, then selection on phenotype can yield higher genetic responses than selection on BLUP. Extra responses by BLUP are at the expense of extra inbreeding. The results derived here show that selection on BLUP of breeding values may not be optimal in all cases. Thus, current theory and teaching on selection methods are queried. Revision of the methodology and a reappraisal of the optimization results of selection theory are required.

Animals↗
PubMed1992

Reduced animal model with differential genetic grouping for direct and maternal effects.

Mixed-model equations for the reduced animal model with maternal effects and different genetic grouping of unknown parents for additive direct and maternal effects are derived. The matrices that relate the expected value and the variance of the breeding values of non-parents to the parents, as well as the different contributions of parental and non-parental breeding values, to the resulting mixed-model equations are presented. Mis-specification of additive maternal variance and the additive covariance between direct and maternal effects, arising from missing information on the dams of known individuals with records, is discussed. To avoid an incorrect specification of the variance-covariance matrix of the records without having to invert a nondiagonal variance of the residual terms, the breeding values of the unknown dams of individuals with records are included in the equations. Breeding values of non-parents are back-solved after the solutions for genetic groups and breeding values of parents are computed as simply as in cases in which maternal effects are absent. A numerical example is included to illustrate the derivations.

Animals↗
PubMed1992

Predictors of dating violence: a multivariate analysis.

A multivariate approach was used to determine the pattern of predictors associated with engaging in dating violence. Predictors were selected whose relationship to dating violence has been established by earlier research: attitudes toward violence, sex-role attitudes, romantic jealousy, general levels of interpersonal aggression, verbal aggression, and verbal and physical aggression received from one's partner. Participants included 305 introductory psychology student volunteers (227 females and 78 males) who completed a set of scales related to dating relationships. Expecting different patterns of predictors to emerge for men and women, we performed separate multiple regression analyses for each. Of the set of predictors employed, receipt of physical violence from one's partner emerged as the largest predictor of expressed violence for both men and women. In addition, higher scores on attitudes toward violence and verbal aggression, and less traditional sex-role attitudes emerged as significant predictors of expressed violence for men. For women, less accepting attitudes toward violence, more traditional sex-role attitudes, feelings of romantic jealousy, higher general levels of interpersonal aggression, and verbal aggression were predictive of expressed violence. The implications of our findings for future research are discussed.

Adult↗
PubMed1992

Clinical results from the calcitite-coated press fit APR hip system.

Hydroxyapatite (HA)-coated APR Total Hip Replacement was found to be superior to a press-fit only control group in a randomized trial. This study confirms the importance of biologic fixation for durability of total hip replacement as compared with press-fit fixation only.

Adult↗
PubMed1992

Iatrogenic denial.

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Denial, Psychological↗
PubMed1992

The Missouri Cardiovascular Health Plan: a focus on prevention.

The authors describe a framework for planning, implementing, and evaluating cardiovascular health programs in Missouri. Populations targeted for intervention are identified, and the role of the physician in supporting community-based cardiovascular health promotion is explored.

Black or African American↗
PubMed1992

Screening for alpha-thalassemia. Correlation of hemoglobin H inclusion bodies with DNA-determined genotype.

We evaluated potential screening protocols for alpha-thalassemia in a group of 80 patients whose genotypes were determined by Southern blot analysis with alpha- and zeta-globin DNA probes. Erythrocyte inclusion bodies were measured by a modified brilliant cresyl blue test. Erythrocyte indices and iron status were also measured. The brilliant cresyl blue test reliably detects couples at risk for hemoglobin Bart's hydrops fetalis. Measurement of the number of inclusion bodies differentiates the alpha-thalassemia genotypes in the absence of a coincident beta-chain synthesis deficiency, such as hemoglobin E or beta-thalassemia. The test appears to identify patients, such as those with the Thai and Filipino deletion variants, whose alpha-thalassemia cannot be definitively characterized by DNA testing when only alpha- and zeta-globin probes are used in the analysis. We also found evidence of elevated serum ferritin levels in many patients with deletion of two or three alpha-globin genes. This study shows that most routine screening for alpha-thalassemia can be performed with three simple tests: (1) the brilliant cresyl blue inclusion study, (2) erythrocyte indices, and (3) iron studies. Analysis with DNA probes is needed in only some circumstances.

Blotting, Southern↗
PubMed1992

Defense style and adaptation in adolescents with depressions and eating disorders.

Maturity of defense style has been associated with the level of adaptive functioning, but few studies have assessed defense style using self-report questionnaires which can provide ratings with great reliability and objectivity. We compared self-perception of defense style (using Bond's Defense Style Questionnaire) with ratings of adaptation assessed retrospectively by two independent raters (using the DSM III-R Global Assessment of Functioning scale) in a population of 100 adolescent girls diagnosed as having either an eating disorder or depression. There was significant correlation between maturity of defense style and level of adaptation, with greater maturity of defense style being associated with higher levels of adaptive functioning. This effect was independent of diagnosis within this population.

Adaptation, Psychological↗
PubMed1992

Does primary Streptococcus viridans pneumonia exist?

In 4 adult black patients admitted to an urban general hospital with community-acquired pneumonia, Streptococcus viridans alone was isolated from blood culture (first subculture), in the absence of any other positive microbiological finding. Sputum examination by Gram staining and culture in 3 cases was reported as negative. Echocardiography was performed in 3 cases and was normal, without evidence of endocarditis. The clinical course of illness in the 4 patients is described. The chest radiograph showed a segmental or subsegmental consolidation in all cases; this appeared 'mass-like' in 2 patients. Viridans streptococci may be a more important, if still uncommon, cause of community-acquired pneumonia than previously suspected. The organism should be considered as a possible cause of chest infection, particularly in patients with appropriately positive blood cultures and no other positive microbiological finding.

Adult↗
PubMed1992

Respiratory stridor and repressive defense style in adolescent somatoform disorders.

Three cases of adolescents with respiratory stridor of psychiatric etiology are described. All three fulfilled DSM-III-R criteria for diagnoses of somatoform disorders and showed characteristics of repressive defense style. Such patients are likely to undergo extensive medical investigation and treatment if the psychiatric nature of their disorder is not recognized, but few data describing their psychological characteristics or treatment exist. Repressors are typically unaware of emotional arousal and do not recognize the negative affects which lead to their somatic symptoms. They therefore respond poorly to confrontational psychotherapy and are at risk of discontinuing treatment and repeating their maladaptive symptom cycle. Identification of repressive defense style in patients with stridor which has no obvious organic cause may be useful both as a possible "marker" of psychiatric disorder and as a guide to treatment.

Adolescent↗