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Biomedical subjects

J Rosenthal

Publications and source records attributed to J Rosenthal.

At least 109 records · Page 6Linked to original sources
PubMed1991

Catecholamines and the renin-angiotensin-aldosterone system during treatment with felodipine ER or hydrochlorothiazide in essential hypertension.

The neurohumoral responses after 10 mg of felodipine extended release (ER), a new dihydropyridine calcium antagonist, and 25 mg of hydrochlorothiazide (HCTZ) were compared in a randomized, double-blind, crossover trial in 28 mild to moderate hypertensives. Antihypertensive drugs were gradually discontinued. Felodipine ER, 10 mg was given once daily for 2 weeks; after another washout period of 1 week, patients were switched to 25 mg of HCTZ once daily and vice versa. Blood pressure (BP) was measured at baseline, 2.5 h after medication, and after 2 weeks of treatment (24 h postdosing) using an oscillometric device. Felodipine ER and HCTZ both lowered BP effectively. However, felodipine ER was superior in reducing systolic and diastolic BP during the short term and medium term. Treatment with felodipine ER over 2 weeks increased sympathetic outflow as indicated by elevated plasma norepinephrine levels, whereas plasma epinephrine was mainly unaffected, as were plasma renin and aldosterone levels. On the other hand, 25 mg of HCTZ increased plasma renin and aldosterone, but left catecholamines unchanged. Despite persistent increased sympathetic activity, the reduction in BP in this study was more pronounced after felodipine ER as compared to HCTZ. The lack of a difference between heart rates under both medications after 2 weeks of treatment suggests a resetting of the baroreflex by felodipine ER and furthermore that the increased norepinephrine levels may not be clinically relevant, but demonstrate the maintained baroreflex activity. HCTZ, in doses as low as 25 mg, is still capable of stimulating the renin-angiotensin-aldosterone system.

Adult↗
PubMed1991

Effects of felodipine ER and hydrochlorothiazide on blood rheology in essential hypertension--a randomized, double-blind, crossover study.

The haemorheological effects of felodipine extended release (ER), a new dihydropyridine calcium antagonist, were compared with hydrochlorothiazide (HCTZ) in 28 mild to moderate hypertensives (18 men and 10 women, aged 30-70 years) in a randomized, double-blind, crossover trial. Antihypertensive drugs were gradually discontinued. Felodipine Er, 10 mg, was given once daily for 2 weeks, and after another wash-out period of 1 week, patients were switched to 25 mg HCTZ, once daily, and vice versa. Whole blood viscosity (BV) at three different shear stresses, haematocrit (Hct), plasma viscosity (PV), red blood cell (RBC) aggregation, RBC deformability, and fibrinogen were measured under standardized conditions 2.5 h after medication, and after 2 week of treatment (24 h post-dosing). Felodipine ER improved BV acutely, but not during treatment over a 2-week period. By contrast, HCTZ did not affect BV, but decreased RBC deformability 2.5 h after medication intake. After 2 weeks of treatment, the negative effect on RBC deformability had increased slightly. Furthermore, fibrinogen and PV were significantly elevated at this stage. In summary, felodipine ER did not improve blood rheology over a 2-week treatment period in this study. HCTZ exhibited marginal but significant negative effects on fibrinogen, PV and indices of RBC deformability, but not on RBC aggregation.

Adult↗
PubMed1991

Aspects of chronic oral treatment with thyrotropin-releasing hormone: the hypothalamic-pituitary-thyroid axis in rats. A study with a pharmacological dose of thyrotropin-releasing hormone.

The effects of 16 days of oral treatment with thyrotropin-releasing hormone (TRH, 1 mg/24 h) on serum levels of thyrotropin (TSH), thyroxine (T4) and triiodothyronine (T3) and the kinetics of TRH in the blood were studied in normal rats. A second group of animals served as controls. TRH was dissolved by sonification (10 mg/l) and was stable in tap water. TRH was measured by a radioimmunoassay procedure (normal range: 20-80 pmol/l, antiserum K2B9 1:120,000 final dilution). An increase in basal TSH (7,200 +/- 440 ng/l, mean +/- SD) was found after 2 days of treatment (11,420 +/- 810 ng/l), but a significant increase was observed after 5 days of treatment (12,530 +/- 640 ng/l, p less than 0.001). T4 serum concentrations remained in the normal range during the entire period of study, whereas T3 serum concentrations (0.76 +/- 0.1 micrograms/l) were increased to 1.22 +/- 0.2 micrograms/l on day 5 (p less than 0.001). A subsequent decline of TSH, T4 and T3 up to the end of the study was observed. TRHmax concentrations were registered on day 5 (790 +/- 24 pmol/l). The mean value of TRHmax was 723 +/- 34 pmol/l. To improve the stability of TRH in tap water, 1-ml samples of drinking water with dissolved TRH were measured. The mean TRH concentration in drinking water was 73 +/- 1.5% (SD). No significant correlations were found between the area under the curve of TSH (184,340 ng.l-1.24 h) and that of TRH (14,954 pmol.l-1.24 h).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

The appeal cycle in early mother-child interaction: nature and implications of a finding from developmental research.

The appeal cycle was observed and delineated through research on mother-child interaction during the second year of life. As a repeated, circumscribed unit of developmental interaction, it is conceived to be an agent of developmental process and psychic structure formation. The appeal cycle has four phases: the adaptational phase, the distress phase, the appeal phase, and the interactional phase. The progression from the adaptational into the distress and appeal phases evidences the child's separation anxiety and failure of self-regulation in response to the experimentally induced attenuation of the mother-child relationship. A successful interactional phase reestablishes the relationship, regulates and restores the child's emotional equilibrium, and enables a return to self-regulation and adaptation. Because the interaction reinforces the functions and structures being developed through identification with the mother, the interactional phase is conceived to be an instrumental event in the mediation of psychic structure formation. The appeal cycle is discussed in comparison with similar phenomena in earlier phases of development and with other studies addressing development during the first two years of life. Directions for future research are noted.

Adaptation, Psychological↗
PubMed1991

Effect of angiotensin-converting enzyme inhibition on human tissue renin.

This investigation was performed to assess the effect of treatment with an angiotensin-converting enzyme (ACE) inhibitor, ramipril, on human tissue renin levels. A total of 41 patients were studied (32 males and 9 females, aged 48-71 years). Twenty-two of these patients received up to 5 days treatment with the ACE inhibitor ramipril (5 mg p.o.) prior to surgery, the remaining 19 patients served as controls (no ramipril treatment). Under surgery vascular tissues were removed and renin-like activities measured in carotid and renal arteries. Plasma renin and ACE activity were determined before and after surgical intervention. Vascular renin values were two- to threefold higher in ACE-treated hypertensive patients compared to normotensive and untreated hypertensive controls (irrespective of concomitant atherosclerotic lesions). There were no differences in vascular renin observed between primary (essential) and secondary hypertension. In the hypertensive patients treated with ramipril, blood pressures were markedly (but not significantly) lowered in 12 patients. A similar pattern was observed for treatment-induced changes in plasma renin (increased) and ACE activity (decreased). The findings of this study demonstrate that treatment with an ACE inhibitor, such as ramipril, evokes changes in extrarenal tissues similar to those demonstrable in plasma. Conceivably, the blood pressure-lowering effect of ACE inhibition on human tissue is partially induced at the vascular level.

Aged↗
PubMed1991

The psychiatric discharge summary: a tool for management and audit.

The aims of this study were to review the information needs of general practitioners in relation to the discharge of mentally ill patients; to design a discharge summary that would meet these needs and evaluate its use by junior hospital staff; and to assess the usefulness of this summary for audit. The information needs of general practitioners were identified from a review of the literature and from discussions with local general practitioners. A prototype discharge summary was designed and reviewed by a panel of general practitioners, regional advisors and course organizers from the south east Thames region. It was used for all patients discharged from the acute psychiatric ward in Hither Green Hospital over a 10 month period. One copy was given to the patient to take to the general practitioner, one was posted to the general practitioner and a final copy was kept in the patient's hospital records. The senior house officers found the summary easy to complete. It reduced uncertainty about what data to provide, and helped to focus on the most critical information needed by general practitioners for continuity of care. Using a pre-coded data collection sheet, analysis of the information on the summaries was easily done. It provided a rapid audit of caseload, diagnoses, therapy, methods of admission and discharge, length of stay, risk factors and roles of all involved in future management. This information can be of use to the psychiatric team, general practitioners and hospital managers and could be the first step towards the development of shared care.

Communication↗
PubMed1991

Thyrotropin releasing hormone (TRH) immunoreactivity and thyroid function in obesity.

Circulating TRH-immunoreactive levels, the thyrotropin response to a TRH intravenous stimulation (200 micrograms) and thyroid hormone concentrations have been determined in 43 overweight subjects (body mass index 45 +/- 12 kg/m2, mean +/- s.d.) and 46 (body mass index 22 +/- 2 kg/m2) normal weight controls. The TRH levels measured by a recently developed, highly specific radioimmunoassay were similar among both groups (44 +/- 16 vs 40 +/- 12 fmol/ml, n.s.). The pattern of response of TSH to TRH was normal in the obese and no significant difference was observed between the peak TSH values of the obese and the normal group (8.3 +/- 2.8 vs 8.7 +/- 2.2 microU/ml, n.s.). No correlations were found between the degree of obesity and the concentrations of TRH, TSH and peripheral thyroid hormone levels. Three obese patients showed a delta-TSH of 18, 19 and 21 microU/ml at normal thyroid hormone concentrations as sign of latent hypothyroidism. These data indicate that in obesity: (a) the TSH response to i.v. TRH is not impaired, (b) circulating TRH-IR levels are not significantly changed and (c) the incidence of overt hypothyroidism is not increased.

Adult↗
PubMed1990

Single-compartment model analysis of thyrotropin-releasing hormone kinetics in hyper- and hypothyroid patients. Kinetic studies using a combined system of RIA and FPLC.

The pharmacokinetics of thyrotropin-releasing hormone (TRH) were assessed following an i.v. injection in blood of ten hyperthyroid, ten hypothyroid, and six normal subjects. A single-compartment model was employed. After methanol extraction, TRH concentrations were analyzed using a specific radioimmunoassay technique combined with fast protein liquid chromatography (FPLC). As for the basal levels of TRH, no differences were observed in either study group. Peak concentrations were always present two min after the injection of TRH. In the euthyroid subjects, TRH blood levels had a half-life (t1/2) of 6.5 +/- 0.41 min, mean +/- SD, while t1/2 was 7.2 +/- 0.62 min in the hyperthyroid and t1/2 was 12 +/- 1.67 min (p less than 0.001) in the hypothyroid patients. The metabolic clearance rate (MCR) (82.2 +/- 15.3 liters/m2/day vs. 89.8 +/- 17.2) and the volume of distribution (Vd) (7.1 +/- 4.2 liters vs. 7.3 +/- 3.4) were approximately the same in the normal subjects and in the hyperthyroid group. MCR (66.2 +/- 15.3 liters/m2/day) and Vd (6.2 +/- 3.3 liters) were found to be lower in the hypothyroid patients. In FPLC, when TRH was added to plasma, it eluted in one peak. Blood samples taken 5 min after TRH i.v. injection had an elution profile of 9.94 ml. These data indicate that 1) TRH has a very short half-life, 2) hypothyroidism can prolong the t1/2 of exogenous TRH, and 3) when TRH should be used in clinical studies, the function of the thyroid gland has to be taken into consideration.

Chromatography, Liquid↗
PubMed1990

Case-control study of in situ and invasive carcinoma of the vagina.

A case-control study of 41 patients with carcinoma in situ (CIS) or invasive cancer of the vagina and 97 community controls was undertaken to identify potential risk factors. Although vaginal and cervical cancers often occur as multiple primaries, only a few common risk factors prevailed. Similar to cervical cancer, low education and family income were risk factors for vaginal CIS and invasive cancer. In addition, history of genital warts was strongly related (RR = 2.9), although other sexual factors were not. Previous genital abnormalities related to subsequent cancer risk, with significant associations seen for vaginal discharge or irritation (RR = 6.1), a previous abnormal Pap smear (RR = 3.8), or an early hysterectomy (RR = 6.7). In addition, there was some evidence that vaginal trauma might be involved, with nonsignificant and independent associations relating to regular douching with preparations other than water or vinegar (RR = 2.7) and frequent washing of the genital area (RR = 2.7). Further studies are needed to determine whether our findings persist among a larger series of cases.

Adult↗
PubMed1990

Treatment of advanced transitional cell carcinoma of the bladder with irradiation and concomitant 5-fluorouracil infusion.

Twenty patients with advanced transitional cell carcinoma of the bladder were treated with radiation and concomitant continuous infusion of 5-fluorouracil with or without Mitomycin. Nineteen of 20 patients were assessed for response. Fourteen of 19 patients (74%) obtained a complete response within 3 to 6 months. An additional three patients (15%) acquired and maintained a complete response after local transurethral resection of the tumor and intravesical chemotherapy, raising the overall complete response (CR) rate to 17/19 (89%). Of the two patients with persistent disease, one is alive and well after salvage cystectomy. Eighteen of 20 patients were evaluated for survival with a median follow-up of 38 months. Seven patients remain alive and well 51 to 78 months, whereas three patients died from intercurrent disease. Eight patients died of either distant metastatic disease (7 patients) or regional disease (1 patient). An adjusted survival calculated by the Life Table Method was 53.6% at 5 years, whereas the overall survival was 39%. The combined modality therapy was well tolerated with no need for treatment interruption or reduction in dose. Late bladder complications include one patient with hemorrhagic cystitis, two patients with dysuria, and two with symptoms of irritable bladder. One patient required a colostomy for a chronic hemorrhagic proctitis. Bladder preservation was achieved in 19/20 patients.

Aged↗
PubMed1990

Immunity of fetal mice to prenatal administration of the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.

Subcutaneous injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) HCl (25 mg/kg) in pregnant female mice at the 17th day of gestation markedly depleted striatal dopamine (DA) concentrations in the mothers 24 h later and at 24 h and 28 days after delivery. By contrast, in the offspring of the female mice exposed to MPTP during pregnancy, fetal brain DA concentrations at 24 h after injection and at 24 h after birth and striatal DA levels at 14 and 28 days postnatally were unaffected and identical to those in age-matched controls. The postnatal ontogenesis of striatal DA levels was identical in offspring of control vehicle- and MPTP-treated pregnant mice. Also, prenatal challenge with MPTP did not make nigrostriatal DA neurons more vulnerable to a second postnatal treatment with the toxin. Striatal DA depletions were identical in 6-week-old mice given MPTP, whether they were exposed to MPTP or to vehicle in utero. Monoamine oxidase (EC 1.4.3.4; MAO) type B activity was extremely low in the fetal brain and, relatively, much lower than that of MAO-A. Prenatal MPTP administration reduced maternal striatal and also embryonal brain MAO-B activity at 24 h post treatment but did not alter the normal postnatal development of striatal MAO-A and -B activities in the offspring. Study suggests that resistance of fetal DA neurons to the DA-depleting effect of MPTP may be due, at least in part, to an absence in the embryonal brain of adequately developed MAO-B activity required for the conversion of MPTP to its toxic metabolite, 1-methyl-4-phenylpyridinium ion.

Aging↗
PubMed1990

Reninlike enzymes in human vasculature.

The present study was designed to identify angiotensin I (Ang I)-forming angiotensinogenases in human extrarenal vasculature and to examine the theory of Jiménez Días on their stimulation in essential hypertension. Vascular sections obtained intraoperatively from 14 normotensive and 16 hypertensive patients undergoing corrective surgery, 68 umbilical cord blood vessels from parturient women, tissue samples from nine explanted hearts, and serum from anephric and healthy individuals were investigated. Ang I-forming angiotensinogenase activities were determined enzyme-kinetically by using Ang I radioimmunoassay and purified sheep or human angiotensinogens. Three nonrenin Ang I-forming angiotensinogenases (pH optima of 4.0, 5.1, and 6.1) were identified in extrarenal vasculature, in cardiac tissues, and in plasma. Highest specific activities of nonrenin Ang I-forming angiotensinogenase (in nanograms Ang I per gram times hour; mean +/- SD) were found in cardiac tissue (2,821 +/- 497, n = 9), followed by carotid artery intima (1,448 +/- 982, n = 10), arteries (1,307 +/- 736, n = 18), and umbilical cord arteries (135 +/- 55, n = 35). Extrarenal arterial Ang I-forming angiotensinogenases were linearly correlated with those of local angiotensin converting enzyme and plasma renin activity. In essential hypertension, extrarenal arterial Ang I-forming angiotensinogenases were scattered, but not generally stimulated. The data obtained indicate the existence of nonrenin Ang I-forming angiotensinogenases in human extrarenal vasculature, in kidney, and in plasma. The postulate of stimulation of extrarenal arterial Ang I-forming angiotensinogenases in essential hypertension cannot be supported. Similar to the classification of plasma renin activity, a classification of Ang I-forming angiotensinogenase activity is proposed, consisting of patients with essential hypertension divided into subgroups exhibiting high, normal, or low vascular Ang I-forming angiotensinogenase activities.

Angiotensin I↗
PubMed1990

An exploratory study of mother-child interaction during the second year of life.

The aim of this study was to further understanding of development during the crucial second year of life. The study employed a naturalistic, semistructured situation for the observation of mother-child behavior. The experimental stimulus was the progressive diversion of the mother's attention away from her child. This diversion evoked separation anxiety in the child and the individual and interactive regulatory behaviors of the mother-child pair. Concurrently, the child's behavior was observed in a play group situation. One set of rating scales was devised for assessment of the mother-child interaction, and another set for assessment of the child's functioning in the play group. The major hypothesis was that maternal and child behaviors that foster the child's successful handling of phase-specific stresses and developmental tasks will be positively correlated with the child's functioning in the play group. This hypothesis is supported by the findings of the study.

Dependency, Psychological↗
PubMed1990

[Effect of chronic renal failure and hemodialysis on the pancreas-specific enzyme pattern in the serum].

Amylase concentration in serum is frequently found increased in chronic renal insufficiency without being associated with pancreatic diseases. A prospective study was performed in 71 patients with chronic renal insufficiency undergoing hemodialysis for comparison of different pancreatic enzymes in serum. 7 patients were not considered in this comparative study because of chronic pancreatitis-like-changes in ultrasound. Increased serum concentrations were found for total amylase in 27 patients (42.2%), pancreatic amylase in 26 patients (25.0%), lipase in 50 patients (78.1%), immunoreactive trypsin in 61 patients (95.3%) and for elastase 1 in 7 patients (10.9%). Hemodialysis did not affect any of the investigated pancreatic serum-enzymes. Elastase 1 determination in serum appears superior to the other pancreatic serum-enzymes because of higher specificity, not limited by renal insufficiency. The different serum concentration of elastase 1 and trypsin, which have a similar molecular weight, points towards a completely different clearance mechanism for these enzymes.

Adolescent↗
PubMed1990

Efficacy of long-term fluoxetine treatment of obsessive-compulsive disorder.

Ten outpatients meeting DSM-III-R criteria for obsessive-compulsive disorder completed a 32-week, open-label study with fluoxetine, a selective serotonin reuptake blocker. The patients were evaluated every four weeks for obsessive-compulsive symptomatology, anxiety, and depression. Significant improvement of obsessive-compulsive and anxiety measures were observed after four weeks, with maximal improvement at eight weeks. Depressed and nondepressed patients showed similar rates of improvement in obsessive-compulsive symptomatology. Overall, fluoxetine was tolerated well by all patients, and no serious side effects were observed. This study suggests that fluoxetine is an effective and safe treatment for obsessive-compulsive disorder, both for short-term alleviation and for long-term maintenance.

Body Weight↗