PubMed Health⌕ Search

Biomedical subjects

W G Hart

Publications and source records attributed to W G Hart.

15 recordsLinked to original sources
PubMed2000

No evidence for multiple-drug prophylaxis for tuberculosis compared with isoniazid alone in Southeast Asian refugees and migrants: completion and compliance are major determinants of effectiveness.

BACKGROUND: The use of multiple-drug prophylaxis for tuberculosis (TB) has not been shown to be more effective than prophylaxis with isoniazid alone. The boundary between inactive pulmonary TB (class 4 TB) and culture-negative "active" pulmonary TB (class 3 TB) is often unclear, as is the intention to treat such patients as a preventive measure or as a curative measure. METHODS: We compared the effectiveness of single drug preventive therapy with isoniazid to the effectiveness of multiple drug preventive therapy for patients with asymptomatic, inactive TB, in a retrospective cohort study of 984 Southeast (SE) Asian migrants and refugees who received prophylaxis between 1978 and 1980. RESULTS: The rate of TB developing in this cohort was 122 per 100,000 person-years. There was no significant difference in development of TB between people who received isoniazid only and those who received multiple drugs. The only significant predictor of TB was noncompletion of prophylaxis [relative risk (RR) = 62, 95% confidence interval (CI) = 20-194]. Subgroup analysis on people who had completed therapy showed noncompliance as a significant predictor of TB (RR = 16, 95% CI = 1.4-179). The risk of noncompletion (RR = 4.7, 95% CI = 2.37-9.39, P < 0.0001) and noncompliance (RR = 2.2, 95% CI = 1.03-4.7, P = 0.03) was higher for patients who received multiple drugs compared with isoniazid alone. Multiple-drug therapy cost 30 times more than isoniazid alone. CONCLUSIONS: We did not find evidence in support of the empirical practice of giving multiple drugs for prevention of TB. This practice is also more costly and more likely to result in noncompliance and adverse drug reactions.

Adult↗
PubMed2000

In-hospital mortality and associated complications after bowel surgery in Victorian public hospitals.

BACKGROUND: The purpose of the present paper was to determine the mortality rate and associated complications after large bowel resection and anastomosis in Victorian public hospitals. METHODS: A retrospective analysis of data from the Victorian Inpatient Minimum Database (VIMD) was undertaken. The data were collected from all Victorian public hospitals performing hemicolectomy and anterior resection (resection of the rectum with anastomosis) from 1987/88 to 1995/96. RESULTS: A total of 11036 patients underwent hemicolectomy or anterior resection in the time period studied, there being a 7% increase in the rate of operations performed over the 9 years. Two-thirds of these operations were for carcinoma of the large bowel. The anastomotic leak rate of 4.5% fell slightly but the in-hospital mortality rate of 6.5% did not change over the study period. The total morbidity recorded (mainly major complications) was 24.6%. The patients most at risk of death were the elderly with pre-existing cardiac or respiratory disease undergoing an emergency operation. CONCLUSIONS: Notwithstanding some inaccuracies of coding and reporting, the morbidity and mortality for surgery of the large intestine remains high, largely due to the comorbidities of the patients, although certain technical complications such as leakage of an anastomosis after anterior resection are still associated with a significantly increased risk of death. Consideration should be given to the routine use of high-dependency nursing units for these high-risk patients after major colorectal surgery, and support from physicians to reduce morbidity and mortality from associated medical conditions worsened by surgery.

Anastomosis, Surgical↗
PubMed1994

Effect of terminal (dry) heat treatment on non-enveloped viruses in coagulation factor concentrates.

Terminal dry heat treatment effectively inactivated hepatitis A virus (HAV) and canine parvovirus added to high-purity factor VIII. After 24 h at 80 degrees C, HAV infectivity was reduced by > or = 4.3 log10 TCID50, as measured in a newly developed infectivity assay. The same reduction in virus titer was achieved after 2 h and before 6 h at 90 degrees C. Inactivation of hepatitis A virus was also seen in the freeze-drying step prior to heat treatment with an approximately 2.0 log10 reduction in titer. Similar results were obtained with a high-purity factor IX concentrate. Canine parvovirus was also inactivated at both temperatures, with residual infectivity being undetected after 48 h at 80 degrees C or 10 h at 90 degrees C. Canine parvovirus was not affected by lyophilisation. Canine parvovirus measurements by PCR did not reflect the levels of infectivity measured by the tissue-culture-based method. The addition of the terminal dry heat treatment to solvent/detergent could effectively eliminate the potential contamination of solvent/detergent-treated coagulation factor concentrates by non-lipid-enveloped viruses. However, careful evaluation for any increased induction of non-antigens for factor VIII, as a consequence of such treatment, is needed before use in patients can be recommended.

Animals↗
PubMed1993

A comparison of polymerase chain reaction and an infectivity assay for human immunodeficiency virus type 1 titration during virus inactivation of blood components.

Three examples of human plasma-derived concentrates, intermediate-purity factors VIII and IX, and fibrinogen were spiked with tissue culture-grown human immunodeficiency virus type 1 (HIV-1) strain RF. All examples were freeze-dried and heated at 80 degrees C for 72 hours by using validated production process models. HIV-1 infectivity was measured by a syncytial infectivity assay in C8166 cells and then compared with levels determined by nested HIV polymerase chain reaction (PCR). The infectivity assay demonstrated a reduction index of at least 4.5 log10, while PCR showed an average 1.7 log10. Large amounts of HIV-1 RNA (10(5)) were still detectable by PCR in samples in which infectivity assays failed to detect any HIV-1. These data suggest that HIV-1 PCR levels do not parallel HIV-1 infectivity levels during virus-inactivation procedures involved in coagulation factor concentrate production. PCR was able to detect the RNA associated with inactivated HIV-1 particles in the factor concentrates, which allows the conclusion that PCR is not a useful test with which to monitor virus-inactivation procedures such as heating at 80 degrees C for 72 hours. This judgment contrasts with the more definite and sensitive role of PCR in diagnosing HIV-1 infection in patients in whom a positive HIV-1 PCR result correlates with active HIV-1 infection and with PCR's usefulness in monitoring virus removal.

DNA, Viral↗
PubMed1989

Use of aerial color infrared photography as a survey technique for Psorophora columbiae oviposition habitats in Texas ricelands.

This study investigated the possibility of using aerial color infrared (CIR) photography as a survey technique for egg populations of Psorophora columbiae within a riceland agroecosystem. To accomplish this, eight photographic missions were flown over study fields during a variety of seasons and at various altitudes. Assessment of resulting photographic data indicates features reported in the literature as being attractive for oviposition by Ps. columbiae (i.e., rice field levees, tire tracks, ditches and low areas) can be readily detected on aerial CIR photographs. Features associated with Ps. columbiae oviposition sites were easily visible on photographs at scales as small as 1:42,000.

Aircraft↗
PubMed1987

Psychiatric screening in the premenstrual syndrome.

Prospective daily ratings of premenstrual symptomatology were obtained from 40 women for one full menstrual cycle. Nineteen of these women were complaining of suffering from a premenstrual syndrome. The General Health Questionnaire (GHQ) was administered in the mid-follicular and late luteal phases of the cycle. Women who were complaining of the premenstrual syndrome showed significant premenstrual increases in premenstrual symptoms, of a magnitude that was significantly greater than those of control subjects. The GHQ scores of the women who were complaining of premenstrual syndrome were significantly higher than those of the control subjects in both the follicular and luteal phases of the cycle. The mean GHQ score of the group with premenstrual syndrome was significantly elevated above the published normal value. Fifty-six per cent of those who complained of premenstrual syndrome had follicular GHQ scores which were higher than the recommended threshold for clinical psychiatric disturbance. Only 10.5% of the control group were above this threshold. General Health Questionnaire scores were stable across phases of the cycle and were correlated to the severity of symptoms of premenstrual syndrome. Premenstrual Moos Menstrual Distress Questionnaire (MDQ) scores were related strongly to follicular MDQ scores. A high proportion of women who complain of premenstrual syndrome show evidence of a more general psychiatric problem which should be evaluated before therapy.

Adult↗
PubMed1987

Assessment of premenstrual symptomatology: a re-evaluation of the predictive validity of self-report.

The predictive validity of subjects' self-reports of the severity of four groups of symptoms associated with the premenstrual syndrome (PMS) was assessed by canonical correlation of retrospective self-reports of usual symptom severities with prospectively obtained symptom severity scores from the next two cycles. Prospective scores from the second cycle were then correlated with retrospective recall scores obtained after the end of that cycle. A measure of inter-cycle variability was obtained by correlation between two consecutive sets of prospective scores. The symptoms studied were tension, depression, cognitive and physical ('water retention') symptoms. It was found that subjects' recall of a particular cycle predicted 72% of the variance in that cycle's prospective severity scores, indicating that the subjects correctly interpreted the severity of premenstrual symptoms and distinguished them from symptoms present in the follicular part of the cycle. Retrospective reports of usual PMS symptomatology predicted 21% of the variance in symptom scores in the next menstrual cycle and 12% of the variance in the following one. Despite this decrease, averaging the scores from the two prospective cycles improved the prediction to 23%. Prospective scores from one cycle predicted only 14% of the variance in prospective scores from the next, suggesting a high degree of inter-cycle variability. Women's self-reports of their usual PMS symptomatology reflect their experience more accurately than has been thought. The finding of marked inter-cycle variability suggests that arguments for the use of a single cycle of prospective data in PMS evaluation are fallacious and that retrospective self-report may be clinically useful and relatively valid.

Adult↗
PubMed1986

A prospective comparison study of premenstrual symptoms.

A study in which two groups of women were compared prospectively has been carried out. One group (n = 31) complained of premenstrual syndrome (PMS) whereas the other group (n = 12) denied suffering from PMS. It was found that premenstrual symptoms increased significantly in women who complained of PMS although some symptoms (irritability, abdominal swelling) increased significantly in the other group as well. The group that complained of PMS showed significantly greater premenstrual increases in some symptoms than did the comparison group, but not in anxiety, irritability, tension or breast tenderness. In the late follicular phase statistically significant baseline differences occurred between the two groups in depression, anxiety, tension and irritability. Significant correlations between baseline and premenstrual scores in the PMS group were found for most of the symptoms that were studied, particularly for tension, anxiety, sleeplessness and depression. These results suggest that women who complain of premenstrual syndrome may require therapy for their generally higher levels of anxiety and depression throughout the entire menstrual cycle rather than for the premenstrual exacerbation alone.

Adult↗
PubMed1984

Processed bovine cartilage: an improved biosynthetic implant for contour defects.

Irradiated human cartilage has been found to be a superior implant material for correction of contour defects; however, availability problems have prevented this material from gaining wide acceptance. Implantation of processed irradiated bovine cartilage in primates and rabbits, as described here, provides strong evidence that this material performs like irradiated allograft cartilage antigenically and has certain cosmetic advantages over allograft cartilage. Our studies in primates have shown that there is no systemically measurable antibody-antigen reaction, either cellular or noncellular, to irradiated processed bovine cartilage. Neither primary nor second-set provocative implantations produced any measurable rejection. In rabbits, composite grafts of two pieces of irradiated bovine cartilage adjacent to each other were also well tolerated, with no measurable absorption and with capsule formation typical of a foreign body reaction to an inert object.

Animals↗
PubMed1978

Blood pressure in the arm and leg in late pregnancy.

Arm and leg blood pressures were measured by an indirect sphygmomanometric method in 12 women in late pregnancy and the results were compared with those in 12 matched non-pregnant women. In most of the pregnant women the diastolic blood pressure measured in the leg fell significantly with a change in posture from the supine to lateral position. In contrast, no significant change was observed in arm blood pressure with postural change after correcting for hydrostatic pressure difference. The interpretation of these findings is discussed with particular reference to methodology of blood pressure measurement.

Adolescent↗