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H Davis

Publications and source records attributed to H Davis.

At least 73 records · Page 4Linked to original sources
PubMed1996

Data-gathering tools for "real world" clinical settings: a multisite feasibility study.

OBJECTIVE: To determine the mental health needs and optimal treatments for children and families in "real world" settings, data-gathering strategies are needed that can be easily implemented across a variety of clinical settings. To address this need, the authors developed and piloted a "clinician-friendly" questionnaire that includes demographic, psychosocial, medical, and family history variables, such as those routinely gathered in standard clinical evaluations. METHOD: Optical scanning technology was used to encode data from more than 1,900 children, including 1,458 consecutive referrals in four military child psychiatry clinics, 285 consecutive admissions to a civilian psychiatric state hospital, 71 pediatric patients, and a community sample of 113 children. RESULTS: Despite geographic and logistic obstacles, clinical data were reliably obtained across multiple settings. Data analyses revealed meaningful differences across samples in subjects' presenting complaints, and a range of psychosocial, demographic, and background variables. Data were characterized by an apparently high degree of accuracy and completeness. CONCLUSIONS: Findings illustrate the importance and feasibility of standardized data-gathering approaches in routine clinical settings and clarify the hazards as well as the opportunities afforded by these research approaches. Such data-gathering tools appear to have significant merit and deserve further implementation and testing across a range of clinical and research settings.

Adolescent↗
PubMed1996

Antiplatelet and antiproliferative effects of SCH 51866, a novel type 1 and type 5 phosphodiesterase inhibitor.

SCH 51866 is a potent and selective PDE1 and PDE5 inhibitor. The antiplatelet, antiproliferative, and hemodynamic effects of SCH 51866 were compared with those of E4021, a highly selective PDE5 inhibitor. SCH 51866 inhibited PDE1 and PDE5 isozymes with a 50% inhibitory concentration (IC50) of 70 and 60 nM, respectively. SCH 51866 and E4021 inhibited washed human platelet aggregation induced by collagen with an IC50 of 10 and 4 microM, respectively, and attenuated (p < 0.05) the adhesion of 111indium-labeled platelets to the nylon filament-injured rat aorta. The doses of SCH 51866 and E4021 that inhibited platelet adhesion caused significant increases in platelet cyclic guanosine monophosphate (cGMP; p < 0.05). SCH 51866 (1-10 mg/kg, p.o. twice daily) but not E4021 (3-30 mg/kg, p.o twice daily) inhibited neointima formation in the carotid arteries of spontaneously hypertensive rats (SHRs) subjected to balloon angioplasty. Moreover, SCH 51866 (0.3-10 mg/kg, p.o.) elicited dose-dependent reduction in blood pressure in SHRs, whereas E4021 (3-30 mg/kg, p.o.) did not affect blood pressure in SHRs. In conclusion, the data suggest that inhibition of PDE1 and PDE5 isozymes by SCH 51866 exerts antiplatelet and vascular protective effects. In comparison, inhibition of PDE5 alone by E4021 exhibited antiplatelet effects without affecting neointima formation.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1996

Six-month supervised intermittent tuberculosis therapy in Haitian patients with and without HIV infection.

We enrolled 427 consecutive patients with tuberculosis diagnosed in Cité Soleil, Haiti in a trial of short-course intermittent therapy. All patients received supervised therapy with isoniazid, rifampin, pyrazinamide, and ethambutol thrice weekly for 8 wk, followed by isoniazid and rifampin thrice weekly for 18 wk. At entry, the 177 human immunodeficiency virus (HIV)-infected patients (42%) were found significantly more likely to have extrapulmonary tuberculosis and negative tuberculin skin tests (p < 0.05). Treatment was well tolerated by both groups of patients, and adherence to the treatment regimen was over 90%. Among patients with pulmonary or intrathoracic tuberculosis, 9% of HIV-seropositive and 1% of HIV-seronegative patients died during therapy (p < 0.001), whereas 81% and 87%, respectively, of those in the two groups were cured. Relapses occurred in 5.4% of HIV-seropositive and 2.8% of HIV-seronegative patients who completed treatment (p = 0.36). Survival after tuberculosis was poorer in HIV-seropositive patients, whose probability of dying was 33% at 18 mo after diagnosis as compared with 3% for HIV-seronegative patients (p < 0.001). HIV-seropositive patients who died had significantly lower median CD4 lymphocyte counts than did HIV-seropositive patients who survived (p < 0.001). Treatment of tuberculosis with short-course, thrice-weekly, supervised therapy in the setting of a developing country is highly efficacious in both HIV-seropositive and -seronegative patients.

AIDS-Related Opportunistic Infections↗
PubMed1996

Paying the price.

Explore the source record for details and available documents.

Anniversaries and Special Events↗
PubMed1996

Effects of wortmannin analogs on bone in vitro and in vivo.

The possible importance of phosphatidylinositol (PI) 3-kinase activity in bone resorption activity in vitro and in vivo were evaluated with synthetic wortmannin analogs in two in vitro bone resorption assays, two in vitro assays for PI 3-kinase activity and for the first time, in two in vivo rat models. Wortmannin and LY301497 were shown to be potent, dose-dependent inhibitors of the bone resorption activity of differentiating chicken osteoclast-like cells and isolated rat osteoclasts. A similar structure/activity profile and potency relationship was observed for the inhibition of osteoclastic activity and of bovine PI 3-kinase activity with purified enzyme, as well as direct inhibition of the PI 3-kinase activity of chicken osteoclast lysates. These in vitro data identified LY301497 as an inhibitor of bone resorption that is 10-fold more potent than wortmannin itself, and the most potent inhibitor of PI 3-kinase activity identified thus far. Wortmannin and analogs also lowered the osteoclast-dependent serum calcium levels like salmon calcitonin in a rat model of secondary hyperparathyroidism. More directly, oral administration of wortmannin analogs prevented the estrogen deficiency-induced loss of trabecular bone in the metaphysis of proximal tibiae from ovariectomized rats. Wortmannin, and especially LY301497, compared favorably in potency in vivo to orally administered estrogen. Taken together, these data are strong evidence to show that wortmannin analogs directly block osteoclastic activity in vitro and in vivo, and confirm that PI 3-kinase activity is a necessary step in the regulation of bone resorption. PI 3-kinase activity appears to be an important component of ovariectomy-stimulated bone loss in rats. This mechanism is supported by the finding that wortmannin had little effect on the activity of myosin light chain kinase in intact osteoclasts. The use of LY301497 should prove useful in elucidating specific molecular interactions important in bone resorption and other PI 3-kinase-mediated cell processes. These data also suggest the possible therapeutic utility of wortmannin analogs to treat conditions characterized by excessive bone loss, such as hyperparathyroidism or hypercalcemia of malignency.

Androstadienes↗
PubMed1996

Young children's cardiovascular stress responses predict resting cardiovascular functioning 2 1/2 years later.

BACKGROUND: Since the pathogenesis of coronary heart disease (CHD) has its origins in childhood, researchers have increasingly evaluated CHD risk factors in youth. In this study we examined the hypothesized behavioral risk factor of cardiovascular responsivity as a predictor of very young children's resting cardiovascular functioning 2 1/2 years later. SUBJECTS AND METHODS: During an initial visit to the laboratory, 97 children (30 blacks and 67 whites, 45 boys and 52 girls) aged 6-7 years completed three laboratory stressor tests (forehead cold pressor, postural change, and treadmill exercise). A comprehensive cardiovascular assessment was conducted during the tests. Resting cardiovascular activity (baseline values) was also assessed. Follow-up resting cardiovascular parameters were measured in the laboratory 2 1/2 years later. RESULTS: Cardiovascular stress responses were predictive of cardiovascular follow-up resting levels 2 1/2 years later. Multiple regression was used to evaluate the independent predictive power of stress responses after controlling for traditional risk factors. Follow-up resting systolic blood pressure (SBP) was predicted by the SBP response to postural change and treadmill exercise. Follow-up resting diastolic blood pressure (DBP) was predicted by the DBP response during treadmill exercise, particularly for blacks. The follow-up resting heart rate was predicted by the heart rate response to the forehead cold pressor and treadmill exercise. CONCLUSION: These results show that in very young children, stress responses are predictive of resting cardiovascular functioning 2 1/2 years later. Further developmental and longitudinal investigations will determine whether such responses are predictive of later preclinical manifestations of cardiovascular disease. If so, incorporation of stress testing in a standardized risk identification protocol might aid the design and practice of cardiovascular preventive medicine.

Analysis of Variance↗
PubMed1996

Widespread HIV counseling and testing linked to a community-based tuberculosis control program in a high-risk population.

The aim of the work reported here was to evaluate community-wide screening for HIV infection that was linked to a tuberculosis control program in a population at high risk for both infections. Between May 1990 and August 1992, adults in Cité Soleil, Haiti, were recruited by community health workers at their homes and in clinics for individual, clinic-based counseling and testing for HIV and tuberculosis. All of the screened subjects were offered post-test HIV counseling. Those with active tuberculosis received treatment, while those with latent tuberculosis and HIV infection were offered an opportunity to participate in a trial of antituberculosis chemoprophylaxis. The 10,611 individuals screened for HIV represented 10.0% of the adult population in Cité Soleil. HIV infection was detected in 1,629 (15.4%) and active tuberculosis in 242 (2.3%). Latent M. tuberculosis infection was found in 4,800 (67.5%) of 7,309 community residents who completed tuberculosis screening, 781 (16.3%) of whom were coinfected with HIV. The high prevalence of HIV infection found in this screened population, as compared to other groups undergoing HIV screening in the same community, suggests that people at high risk for HIV infection selectively sought or accepted tuberculosis clinic screening. Also, many people with active tuberculosis were identified earlier in the course of their disease than they would have been in the absence of a screening program. Overall, the results indicate that community-based screening for HIV infection within a tuberculosis control program can result in effective targeting of screening for both infections.

Adolescent↗
PubMed1996

Changes in attitudes of medical students towards psychiatry: an evaluation of a clerkship in psychiatry.

The attitudes to psychiatry of medical students before and after their clinical rotation in psychiatry were assessed during the course of the academic year 1989-1990 by a questionnaire administered before and after the clerkship. Analysis of the data indicated that although there was no major shift in attitudes, the clerkship did succeed in improving clinical skills such as the capability for a better understanding of patients and the improvement of doctor-patient relations, as well as giving the student a more realistic approach to the diagnosis, treatment and prognosis of mentally ill patients.

Adult↗
PubMed1996

Moderators of ethnic differences in vasoconstrictive reactivity in youth.

Three hundred and forty-one children (170 males and 171 females: 155 whites and 186 blacks) with a mean age of 11.2 years completed laboratory stressors of forehead cold and a video game. Impedance cardiography was used to assess total peripheral resistance indexed by body surface area (TPRI) at rest and during the stressors. Black youths exhibited greater TPRI and mean arterial pressure (MAP) reactivity to both stressors. It was hypothesized that anthropometric, demographic, lifestyle, and psychosocial variables might partially account for ethnicity differences in vasoconstrictive reactivity. Black youths' higher resting MAP and TPRI and greater MAP and TPRI reactivity to forehead cold were accounted for by anthropometric characteristics, physical activity, sedentary behavior (i.e., TV viewing) and family cohesion. The ethnic differences in TPRI and MAP video game reactivity were not accounted for by the various parameters.

Black or African American↗
PubMed1995

Anti-microbial activity and anti-complement activity of extracts obtained from selected Hawaiian medicinal plants.

Selected plants having a history of use in Polynesian traditional medicine for the treatment of infectious disease were investigated for anti-viral, anti-fungal and anti-bacterial activity in vitro. Extracts from Scaevola sericea, Psychotria hawaiiensis, Pipturus albidus and Eugenia malaccensis showed selective anti-viral activity against Herpes Simplex Virus-1 and 2 and Vesicular Stomatitis Virus. Aleurites moluccana extracts showed anti-bacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa, while Pipturus albidus and Eugenia malaccensis extracts showed growth inhibition of Staphylococcus aureus and Streptococcus pyogenes. Psychotria hawaiiensis and Solanum niger inhibited growth of the fungi Microsporum canis, Trichophyton rubrum and Epidermophyton floccosum, while Ipomoea sp., Pipturus albidus, Scaevola sericea, Eugenia malaccensis, Piper methysticum, Barringtonia asiatica and Adansonia digitata extracts showed anti-fungal activity to a lesser extent. Eugenia malaccensis was also found to inhibit the classical pathway of complement suggesting that an immunological basis for its in vivo activity was identified. This study has confirmed some of the ethnobotanical reports of Hawaiian medicinal plants having curative properties against infections using biological assays in vitro.

Anti-Bacterial Agents↗
PubMed1995

Temporal stability of children's cardiovascular (CV) reactivity: role of ethnicity, gender and family history of myocardial infarction.

Cardiovascular responses to three laboratory stressors (i.e., postural change, treadmill exercise, forehead cold) were evaluated in 106 children (72 Whites, 34 Blacks) who varied in family history (FH) of early myocardial infarction (53 positive FH, 53 negative FH). Subjects were evaluated on two occasions separated by one year. In general, regardless of ethnicity, gender or FH, stability of resting blood pressures (BP) and heart rates were comparable to existing data. Resting cardiac output (CO) and total peripheral resistance (TPR) stability estimates were comparable or higher than the BP estimates across groups except for the +FH subjects and males who showed poor stability to one or both parameters. Moderate stability was observed for all parameters in response to forehead cold and low to moderate stability was observed in HR, CO, and TPR postural change reactivity. The only consistent pattern of significant differences in stability estimates involved ethnicity. African-Americans exhibited significantly higher coefficients compared to Whites in TPR at rest and during postural change and forehead cold. Reasons for the low to moderate resting and reactivity stability estimates are discussed.

Black People↗
PubMed1995

Control of sexually transmitted diseases in Haiti: results and implications of a baseline study among pregnant women living in Cité Soleil Shantytowns.

Women attending Haitian slum-based antenatal clinics were evaluated for sexually transmitted diseases (STDs): 110 (11%) of 996 were syphilis seroreactive, 313 (35%) of 903 had trichomoniasis, 110 (12%) of 897 had gonococcal or chlamydial cervical infection (or both), and 418 (47%) of 891 had at least one STD. Syphilis seroreactivity was associated with illiteracy (P = .007), lower socioeconomic status (P < .001), and a history of spontaneous abortion (P = .02). Of 663 evaluated sera, 56 (8%) had human immunodeficiency virus (HIV) antibodies. In multivariate analysis, positive HIV serostatus was associated with syphilis seroreactivity (P = .006), partner's unemployment (P = .002), and history of a previous sex partner (P = .04). Risk factors for gonococcal or chlamydial cervical infection were evaluated. Clinical assessment of cervical discharge, a World Health Organization algorithm, and a decision model based on local risk factors were 64%, 77%, and 89% sensitive, respectively, and 44%, 38%, and 43% specific, respectively, for predicting cervical infection. Alternative treatment approaches should be validated while waiting for affordable, simple, rapid, and accurate laboratory diagnostic tests for gonococcal and chlamydial cervical infections.

Abortion, Spontaneous↗
PubMed1994

Increasing rates of cervical and lumbar spine surgery in the United States, 1979-1990.

STUDY DESIGN: Data from annual national surveys of hospitalizations were used to review trends. OBJECTIVES: The trends in rates of hospitalizations with cervical and lumbar spine surgery were examined among persons > or = 25 years old. SUMMARY OF BACKGROUND DATA: Preliminary analysis of national survey data indicated that during 1979 to 1990 the number of spine operations increased markedly. METHODS: Data from the National Hospital Discharge Survey were used to calculate age-adjusted rates of hospitalizations. RESULTS: From 1979-81 to 1988-90, in each sex, the rate of hospitalizations with cervical spine surgery increased > 45%, with the rates for cervical fusion surgery increasing > 70%. The rate of hospitalizations with lumbar spine surgery increased > 33% in each sex, with the rate for lumbar fusion surgery increasing > 60% in each sex, the rate for lumbar disc surgery increasing 40% among males and 21% among females, and the rate for lumbar exploration/decompression surgery increasing > 65% in each sex. CONCLUSIONS: Between 1979 and 1990, rates of hospitalizations with cervical and lumbar spine surgery increased markedly among both sexes and for different categories of spine surgery.

Adult↗
PubMed1994

Cluster analysis of MCMI and MCMI-II on chronic PTSD victims.

A cluster analysis was used to identify groups of inpatients with confirmed post-traumatic stress disorder (PTSD) due to combat. In Study 1 the MCMI was administered to 256 subjects, in addition to the MMPI, PTSD measures, and background variables. Three clusters resulted: a Traumatic Personality (8-2), Schizoid Influence (8-2-1), and Antisocial Influence (8-6). Comparison on the MCMI symptom scales, MMPI, and PTSD scales showed that the Antisocial Influence cluster was "healthier" on all measures. The Schizoid Influence was most psychopathological. In Study 2 the MCMI-II was administered to 136 new subjects who met the same criteria as in Study 1. Four clusters resulted: Global (1-2-6A-6B-8A-8B), Subclinical (1), Aggressive (6A-6B-8A), and Detached/Self-defeating (1-2-8A-8B).

Adult↗
PubMed1994

Mexican-American mothers' reports of the weights and heights of children 6 months through 11 years old.

OBJECTIVE: To determine the accuracy of mothers' reports of their children's weights and heights. DESIGN AND SETTING: Cross-sectional survey of Mexican Americans in five southwestern states. SUBJECTS: Interviews were held with mothers of 2,578 children aged 6 months to 11 years old. MAIN OUTCOME MEASURES: Sensitivity and specificity of categories formed from reported values, and correlation of reported and measured values. RESULTS: Probability of mothers answering "don't know" was 24% for children's weights and 51% for heights. On the average, mothers overestimated weights at the 15th percentile or lower for age and sex and underestimated weights at the 85th percentile or higher. On the average, they underestimated heights. Categories of low and high weight, height, and body mass index were created by applying absolute-value cutoffs to reported values. All the categories had low sensitivity or specificity. Age-group-specific correlation coefficients between reported and measured values ranged from .79 to .89 for weight and from .32 (for 6- through 23-month-olds) to .70 (for 9- through 11-year-olds) for height. APPLICATIONS: The use of categories formed by applying absolute-value cutoffs to mother-reported values results in frequent misclassification of individuals. Therefore, such categories should not be used to estimate relative risks associated with weight, height, and body mass index. The good correlation of mother-reported and measured weights indicates that despite their inaccuracies, reported weights well reflect the relative ranking of measured weights. Thus, the use of reported weights as a continuous variable in multivariate analyses might cause only small errors in the coefficient for weight.

Body Height↗
PubMed1994

Consistency of children's hemodynamic responses to laboratory stressors.

Hemodynamic responses to three standard laboratory stressors (i.e., postural change, video game, forehead cold) were evaluated in 341 children (170 males) who had a mean age of 11.2 +/- 2.6 years. Inter-task consistency was evaluated for five physiological parameters for all stressor pairings. Evidence of consistency in systolic and diastolic blood pressure, heart rate, cardiac output, and total peripheral resistance responses to all three stressors was observed. The highest and most consistent correlations across stressors were observed for cardiac output and total peripheral resistance responses. The need for clarification in the categorization of laboratory stressors used to measure reactivity is discussed.

Blood Pressure↗
PubMed1994

Self-described weight status of Mexican-American adolescents.

PURPOSE: To evaluate Mexican-American adolescents' descriptions of their weight status. METHODS: Data were from the Hispanic Health and Nutrition Examination Survey, conducted in 1982-1983 among Mexican-Americans in five southwestern states. The current study used data on 429 males and 485 non-pregnant females 12-19 years old. In an interview, participants were asked to describe their weight status (underweight, about the right weight, overweight); in an examination (performed two to four weeks after the interview), weights and heights were measured. Each participant's body-mass index (weight/height2) was calculated, and single year of age-and-sex-specific BMI cutoffs were used to determine each participant's BMI decile. RESULTS: The overweight description was chosen by 46% of females and 23% of males, and the underweight description by 7% of females and 17% of males. The percentage of adolescents self-described as overweight rose with increasing BMI percentile, the rise starting in the 30-39th percentiles for females and in 60-69th percentiles for males. CONCLUSIONS: These findings suggest that many Mexican-American adolescents misperceive their weight status.

Adolescent↗