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Biomedical subjects

A Thomas

Publications and source records attributed to A Thomas.

At least 325 records · Page 18Linked to original sources
PubMed1995

Hepatitis B immunisation among invasive cardiologists: poor compliance with United Kingdom guidelines.

OBJECTIVES: To assess the compliance of invasive cardiologists in the United Kingdom with recently accepted national guidelines on the protection of health care workers and patients from hepatitis B. To determine levels of awareness of the infectivity and prevalence of the virus and current attitudes towards screening of patients before cardiac catheterisation and surgery. DESIGN: Anonymous postal survey by questionnaire from the University Hospital of Wales, Cardiff. The questionnaire established the respondent's position, knowledge of hepatitis B, current immunological state, and policy towards the routine screening of patients for hepatitis B carriage. PARTICIPANTS: All British cardiologists of consultant or senior registrar grade involved in invasive procedures. RESULTS: The response rate was 78% (211/271). 20% of respondents had never been vaccinated against hepatitis B and about a third of those vaccinated had not complied correctly with the recommended immunisation regimen. There was little uniformity in practices for screening patients for hepatitis B carriage before invasive procedures, and the level of knowledge concerning the prevalence of hepatitis B and the risks of inoculation was poor. CONCLUSIONS: Invasive cardiologists are at high risk of inoculation with hepatitis B. Nationally agreed guidelines are designed to protect both medical staff and patients against the risk of infection but currently they are ill heeded.

Attitude of Health Personnel↗
PubMed1995

Association of postprandial triglyceride and retinyl palmitate responses with newly diagnosed exercise-induced myocardial ischemia in middle-aged men and women.

Although strong evidence exists linking fasting plasma levels of LDL cholesterol (LDL-C) and HDL cholesterol (HDL-C) to risk for development of coronary artery disease (CAD), the data in support of an independent role for fasting triglyceride (TG) concentrations are weak. Humans are in the postprandial state most of the day, however, and results from both basic and clinical studies suggest that postprandial TG levels may be atherogenic. Previous studies have not, however, attempted to determine if postprandial TG levels are associated with CAD independent of other traditional risk factors or plasma lipid levels, particularly fasting plasma concentrations of TG and HDL-C. Ninety-two men and 113 women (mean age, 51.6 and 53.6 years, respectively) were recruited from populations undergoing diagnostic exercise electrocardiographic or thallium stress tests at our medical centers. Twenty-six men and 24 women had positive tests. We chose exercise-induced myocardial ischemia (EIM) as the criterion for defining case and control subjects because we wanted participants who did not have a prior diagnosis of CAD. Blood samples were obtained for measurement of plasma TG, TG-rich lipoprotein TG, and retinyl palmitate (RP) levels 2, 3.5, 5, and 8 hours after the subjects had consumed a fatty test meal. Logistic regression models were developed to test for associations between each variable and case-control status. Among men but not women postprandial TG and RP responses were associated with EIMI independent of age, race, and smoking status. In the male group, the odds ratio (OR) for an increase in postprandial TG response of approximately 1 SD was 1.69 (P = .007); the OR for an increase in RP response of 1 SD was 2.47 (P = .011). However, when fasting TG was added to the model, the OR for postprandial TG area in the men was reduced to 1.44 (P = .17); the OR postprandial RP area in the men was reduced to 1.88 (P = .12). There was no effect of adding other risk factors, including LDL-C and HDL-C, to the model. Significant effect modification by body mass index (BMI) on the relationship between postprandial responses and case-control status was observed. In men with BMI < 30, the OR was 1.83 for postprandial TG (P = .041) and 2.77 for postprandial RP (P = .032) in models that included fasting TG, LDL-C, and hypertension.

Age Factors↗
PubMed1995

Effects of a specialized team on stroke care. The first two years of the Yale Stroke Program.

BACKGROUND AND PURPOSE: Strategies have been proposed for stroke care to improve quality or reduce cost. We sought to document the effects of a new program of specialized stroke care. METHODS: In a programmatic review using historical and concurrent control subjects, we evaluated patients discharged with a stroke diagnosis (diagnosis-related group 14) over a 6-year period between January 1987 and December 1992. Patients were from an academic medical center. The intervention was consultation (on university neurology patients) by a specialized multidisciplinary team during the last 2 years of the review period. The main outcome measures were median length of stay and rate of common complications before and after implementation compared with other hospital services (private neurology and medicine). RESULTS: Stroke team involvement was associated with a shortened median length of stay from 10 to 8 days (P < .0001). There was no significant change in the median length of stay for the private neurology or medicine services. After stroke team involvement, there were fewer urinary tract infections (P = .056), and those patients who developed infection had a shorter length of stay (P = .0007). There was no change in the rate of aspiration pneumonia or in length of stay for patients with aspiration pneumonia. Mortality did not change. CONCLUSIONS: A coordinated, multidisciplinary approach to stroke care may reduce length of stay and morbidity in patients hospitalized because of stroke.

Cerebrovascular Disorders↗
PubMed1995

Effect of progesterone on hypothalamic oxytocin messenger ribonucleic acid levels in the lactating rat.

We recently reported that sequential administration of estrogen and progesterone and subsequent withdrawal of progesterone increased the level of hypothalamic oxytocin (OT) messenger RNA (mRNA) in the female rat. Both estrogen priming and progesterone withdrawal are critical components of this regimen. Rats experience this ovarian steroid pattern during certain lactational events such as on days 10-12 of lactation or with interruption of nursing for 48-72 h. In the present study, we used Northern blot and in situ hybridization to determine the association between the steroid exposure and the level of OT mRNA during these lactational conditions. Week 1 lactating rats that had pups removed for 24 and 48 h, but not 12 h, had significantly higher serum estradiol concentrations than animals continuously nursing their pups on a comparable day of lactation (F4, 15 = 6; P < 0.005). Serum progesterone levels declined significantly during the 48 h after litter removal (F4, 15 = 130.5; P < 0.0001). Significant increases in OT mRNA levels were found at 48 h, but not 12 or 24 h, after litter removal (F4, 15 = 4.3; P < 0.02). Implantation of progesterone-filled capsules to compensate for the spontaneous decline in progesterone that occurs with interruption of nursing attenuated this increase in OT mRNA levels. OT mRNA was significantly higher in the hypothalamic paraventricular nuclei (P < 0.0002) and supraoptic nuclei (P < 0.002) of nursing interrupted animals receiving empty vs. progesterone-filled implants. Implantation of day 12 lactating rats with progesterone capsules for 5 days before being killed blunted the increase in OT mRNA that normally occurs on this day of lactation. The data highlight the pivotal role of estrogen priming and progesterone withdrawal in the increased expression of the OT gene during select lactational events.

Animals↗
PubMed1995

Pathophysiological role of dopamine in the kidney: effects in diabetes mellitus and after contralateral nephrectomy.

Both insulin-dependent diabetes mellitus (IDDM) and unilateral nephrectomy (UNX) are associated with an increase in the glomerular filtration rate. Glomerular hyperfiltration has been linked to intraglomerular hypertension in both conditions, although it has only been linked to the development of nephropathy in diabetes. In this study, we examined the possibility of preventing diabetic nephropathy through early dopamine (DA) prodrugs treatment and we also investigated the participation of endogenous DA in the acute functional adaptation of the remaining kidney after UNX. In an animal model of IDDM (steptozotocin-treated Wistar rats), the early increase in the glomerular filtration rate was prevented by treatment with DA prodrugs (L-dopa or gludopa), an effect which was mimicked by fenoldopam (a D1 agonist) and suppressed by carbidopa and SCH 23390 (a D1 antagonist). An increase in endorenal DA synthesis and the subsequent stimulation of vascular D1 receptors appears to prevent early glomerular hyperfiltration in diabetic rats. However, in a long-term study lasting more than one year, streptozotocin-diabetic Wistar rats (unlike to diabetic Munich Wistar rats) failed to develop overt nephropathy characterized by albuminuria and systemic hypertension. During long-term treatment of diabetic rats with L-dopa, the renal availability of DA was diminished. The acute adaptation of the remaining kidney to UNX took the form of an early transient pressor effect with a moderate increase in the glomerular filtration rate and renal blood flow, and a marked decrease in tubular sodium reabsorption. SCH 23390 suppressed the hemodynamic and tubular responses to UNX, suggesting that endogenous DA plays a key role.

Adaptation, Physiological↗
PubMed1995

Visual evoked potentials generator model derived from different spatial frequency stimuli of visual field regions and magnetic resonance imaging coordinates of V1, V2, V3 areas in man.

Visual evoked potentials (VEPs) to pattern reversal vertical bar stimuli were recorded from 24 scalp derivations (including zygomatic and inion) referenced to digitally linked earlobes in 50 controls. 1, 2 and 4 cpd patterns were presented as full field (FF) stimuli, on Upper Hemifields (UHF) and Lower Hemifields (LHF), upper and lower quadrants and with the occlusion of central and peripheral UHF and LHF. VEPs to octant stimuli were also recorded with 2 cpd patterns. N1, P1 and N2 components were recorded from posterior and inion derivations with FF stimuli, from posterior derivations with LHF stimuli, only from inion leads with UHF stimuli, from derivations ipsilateral to stimuli with quadrants and octants, and consistently from midline derivations only with lower quadrants. Polarity inverted sequences (iN1-iP1-iN2) were recorded from the other scalp derivations, with similar latency and spatial frequency sensitivity as N1-P1-N2. Single Equivalent Dipole (ED) calculations were performed on N1 and P1 recorded in the different stimulus conditions. Our findings contradict previous hypotheses on VEP generators and contradict the predictions of VEPs polarity and distribution based on the "cruciform model" of VEPs generators. In order to explain the distribution of VEPs to upper and lower half fields and to quadrant and octants, we propose a model based on the position of the medial and occipito-polar surface of visual cortex in man.

Adult↗
PubMed1995

Perceptions of acute care nurses in the use of restraints.

1. Staff nurses continue to use physical restraints in well-intended efforts to protect patients from potential harm despite the overwhelming evidence of negative consequences from this practice. The use of physical restraints remains an unresolved clinical practice issue. 2. This stratified, random sample demonstrated that LPNs consistently attached greater importance to the use of restraints than either RNs or Managers, suggesting that the educational level of nurses may have an impact on the continued use of physical restraints. 3. The survey further demonstrates that nurses are aware of many alternatives to restraint use. The authors suggest that alternatives may not be widely used because the measures are often not considered practical.

Acute Disease↗
PubMed1995

[The Chinese traditional treatment with "ShengYang" prescription as a post-operative auxiliary method using on the oral squamous cells carcinoma patients.].

This paper observed the clinic investigation.Which prove the relationship among the Chinese dialectical fur condition pulse condition,dialectical divided into types and survival time,immunity function before and after therapy,which will provide scientific basis and new train of thinking for recovery of stomatological carcinoma patient following operation.These patients according to dialectical type.were divided into type of feeble kidney and type of mixed excess and deficiency syndrome that the survive time compare with control group through treat by statistics,were P<0.05.The positive cases of immunity response of administration group were more increased than control group, the rate was 22.2%,maintenance and decrease rate were 7.5% and 14.6% compare with control group,with multiple factor computer analysis in two groups.There is some evidence that the traditional Chinese prescription of "ShengYang" treat in tumor patients with the type of feeble kidney and type of mixed excess an deficiency syndrome were remarkably regulate the immunity function and promote the action of anti tumor.For recovery therapy after tumor operation which reach a fairly action.

English Abstract↗
PubMed1995

Clinical importance of pre-morteum blood lymphocytes in cadaver donor tissue typing.

We have refined our immunomagnetic bead (IM bead) procedures to isolate pure and viable lymphocyte subpopulation from pre-morteum (PM) blood for cadaver donor HLA typing, preliminary and final crossmatches (XMs). The results of 1220 XMs were compared using T/B lymphocytes isolated either from PM blood or spleen/lymphnode (SPLN) tissue. IM bead technique was used to isolate T/B cells from PM blood and nylon wool column (NWC) technique was used to isolate T/B cells from SPLN. When we compared the outcome of 800 T-cell crossmatches using T cells from PM blood or SPLN of 5 separate cadaver donors, NWC TXMs tended to be more falsenegative for high PRA (> 10%, total 500 XMs) as well as low PRA (< 10%, total 300 XMs) did not reach statistical significance. In contrast, NW BXM (420 B XM) were found to be far more false negative than IM bead BXM regardless of the PRA of the patients. In order to ensure that NWC BXMs were indeed false negative, 23 sera with known anti-DR antibodies were BXMed where antigen-specific B cells were isolated by both the techniques. Our results showed that IM bead BXM identified the DR specificities greater than 90% of the time, the titers of ab specificities were stronger (1:8). In comparison, NWB cell XMs were weak (titers 1:2), and the false negative rate for some ab was as high as 73%. Using IM bead and NWC techniques we compared our turnaround time (TAT) for cadaver donor typing, preliminary and final XMs.(ABSTRACT TRUNCATED AT 250 WORDS)

Cadaver↗
PubMed1995

Relapses during long-term follow up with drug-susceptible M. leprae among multibacillary leprosy patients treated with multidrug therapy regimens; case reports.

A controlled clinical trial in highly bacilliferous multibacillary leprosy patients was initiated in 1977. We report here two cases of relapse during long-term follow up of patients 15 years after the start of treatment. The patients reported here were treated with rifampin, isoniazid, clofazimine and dapsone for the first 3 months followed by clofazimine and dapsone until 84 months in one case; the other case received the same treatment but had received dapsone alone for 60-80 months. The relapses occurred 6(1/2) 7(1/2) years after therapy was discontinued.

Drug Therapy, Combination↗
PubMed1995

[Cutaneous localization of T-cell prolymphocytic leukemia].

INTRODUCTION: T cell prolymphocytic leukemia (T PLL) is a rare variant of mature lympho-proliferative disorder. The main physical sign is a gross splenic enlargement contrasting with no enlargement of lymph nodes. Skin involvement is found in 30 p. 100 cases. Twenty-one cases of cutaneous lesions of PLL have been reported, mainly with T PLL, only 2 cases of B PLL: Clinical lesions are polymorphous; histology shows a dermal prolymphocytic infiltrate. The main cytogenetic abnormalities are: translocation (14; 14) (q11; q32), inversion of chromosome 14 (q11; q32), isochromosome 8q. CASE REPORT: We report a case of an 87-year-old patient presenting a T cell prolymphocytic leukemia CD4+ with specific papular lesions of the back. Electron microscopy showed typical prolymphocytes and cytogenetic studies showed a tendency to polyploidy, with the lost of chromosome 14, translocation 8-22 and inversion of chromosome 13. After 12 months of treatment with a combination of chloraminophen and prednisone the patient was in partial remission and the cutaneous lesions disappeared. DISCUSSION: This case is rare and the patient has an unusual long survival (mean survival is 7 months). Contrary to the other hematologic disorders, cutaneous involvement does not change the prognosis of T PLL:

Aged↗
PubMed1995

Effect of gonadal steroids upon hypothalamic oxytocin expression.

Oxytocin (OT) has been implicated in reproductive events. Gonadal steroids, which are also essential for reproduction, may in these instances influence the expression of the OT gene. The relationship between gonadal steroids and OT expression is incompletely understood. First, although estrogen (E) induces OT expression in heterologous in vitro systems and the OT gene contains an estrogen response element, evidence for a stimulatory effect of E upon OT mRNA in vivo as in the rat hypothalamus has been lacking. Second, an enhanced and coordinated expression of OT and vasopressin (AVP), mRNA during late pregnancy and lactation is not expected. This is especially true in lactation, during which suckling selectively activates OT, not AVP, neurons. We now report that E does increase OT mRNA levels in the rat hypothalamus. Ovariectomized rats were implanted initially with E, followed by progesterone (P) 48 hrs later; both were sustained for 12 days and the P implants were removed 48 hrs prior to sacrifice. By in situ and Northern blot hybridizations, OT, but not AVP, mRNA was increased in the hypothalamus of animals receiving this regimen compared to sham treated cohorts. A similar phenomenon associated with exposure to E and P followed by P withdrawal occurs in physiologic states such as day 21 of pregnancy, day 10-12 of lactation, and with interruption of the suckling stimulus for 48 hrs. If E was not administered or if P was not withdrawn prior to sacrifice, no increase was found in OT mRNA. Our data highlight the pivotal role of P withdrawal in the induction of the hypothalamic OT gene in the E-primed rat.

Animals↗