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S Wolf

Publications and source records attributed to S Wolf.

At least 127 records · Page 7Linked to original sources
PubMed1998

Numbers and ratios of X-chromosomal-linked opsin genes.

Quantitative Southern blotting and PCR/RFLP analysis were used to determine the number and ratio of long-wave-sensitive (L-) and mid-wave-sensitive (M-) opsin genes in 25 colour-normal caucasian males. The average observed ratio was 1:2.8 +/- 1.2 for Southern blot analysis and 1:3.0 +/- 1.7 for PCR/RFLP analysis. Thus, the two techniques yielded similar results for the ratio of L- to M-opsin genes (Wilcoxon t-test, P < 0.01). PCR/RFLP analysis of a Sma I polymorphism specific for the most proximal opsin gene suggested an average gene number of 6.0 +/- 2.1, with a range from 4 to 12 in individual subjects. In contrast, Southern blot analysis suggested an average number of 3.8 +/- 1.2, with a range from 2 to 7 (on the assumption that only one L-opsin gene is ever present). Differences between the L- to M-opsin gene ratio and the total gene number in some subjects may result from the presence of multiple L-opsin genes and/or hybrid opsin genes in colour-normal males. An exact determination of the total gene number will require employing other molecular techniques.

Blotting, Southern↗
PubMed1998

Long-term psychosocial adaptation of children who survive burns involving 80% or greater total body surface area.

OBJECTIVE: To examine the psychosocial adjustment of survivors of massive pediatric burn injuries, the change in adjustment across time, and the impact on parents. BACKGROUND: Patients/parents were assessed at regular intervals postburn using standardized tests of adjustment. Patients who could not be included in standardized longitudinal assessments were administered questionnaires by mail/telephone. METHODS: The Child Behavior Checklist, the Teacher Report Form, the Youth Self Report Form, and the Parenting Stress Index were utilized to assess adjustment. RESULTS: On all objective measures, the group of survivors and their parents were within normal limits. Adjustment neither improved nor deteriorated over time. CONCLUSION: Children who survive massive burn injuries can achieve positive psychosocial adaptation.

Activities of Daily Living↗
PubMed1998

Acute effect of metipranolol on the retinal circulation.

AIM: To assess the effect of topical and systemic application of a beta adrenergic receptor blocker on retinal haemodynamics. METHODS: 24 healthy subjects were included in this double masked, randomised, placebo controlled crossover study. Metipranolol, a non-selective beta adrenergic receptor blocking agent was used as test drug. In all subjects arm-retina time, arteriovenous passage time, arterial mean dye velocity, the arterial vessel diameters, and capillary flow velocity were quantified from digital video fluorescein angiograms. RESULTS: A significant effect was observed on the arteriovenous passage time (p < 0.05), the arterial mean dye bolus velocity (p < 0.05), and capillary blood velocity (p < 0.05), but not on the arterial vessel diameter. The arterial mean dye bolus velocity and capillary blood velocity increased after application of the test drug (topical and systemic). In tandem with this a decrease of the arteriovenous passage time was observed. The perfusion pressure increased after topical application and remained unchanged after systemic application of metipranolol. CONCLUSIONS: This study shows that systemic as well as topical application of metipranolol leads to increased retinal blood flow velocities. The implications of these results for treatment with beta adrenergic receptor blockers is not clear. However, in view of these data it is very unlikely that treatment with metipranolol has a negative effect on retinal blood flow.

Administration, Oral↗
PubMed1998

Early rheological and microcirculatory changes in children with type I diabetes mellitus.

In order to determine early changes in microcirculation and hemorheological parameters in diabetics, a cross-sectional study was carried out with 273 children with diabetes mellitus type I during their vacation in a state country convalescent home for diabetic children and teenagers in Kaiserslautern. Compared to healthy children, typical changes of hemorheological variables as well as in the microcirculation of the skin and retina are observed in poorly controlled diabetic children. Morphological changes are obvious in capillary areas in form of marked capillary contortions and dilatations of venous branches, rigid erythrocytes, and hyperaggregable thrombocytes. An effort should be undertaken to normalize the pathologically changed parameters of blood fluidity and the microcirculation by an adequate control of blood glucose, and possibly by changes in dietary habits.

Adolescent↗
PubMed1997

[Renal hemodynamics and proteinuria in chronic glomerulonephritis treated with beta-receptor blockers or ace inhibitors].

BACKGROUND AND OBJECTIVE: In patients with chronic glomerular nephropathy associated arterial hypertension and proteinuria are considered to be cardinal risk factors in the progressive deterioration of renal function. Treatment regimens which reduce proteinuria and hypertension improve prognosis. The effect of the new beta-receptor blockers compared to common ACE-Inhibitors is of special interest. PATIENTS AND METHODS: The studied cohort consisted of 11 patients with CGN, hypertension and proteinuria > 400 mg/24 h. Four drugs were given for 4 weeks, doubly blinded and randomized according to a "Latin-square design": Celiprolol (beta-1-antagonist, beta-2-agonist, 200 mg/d), Atenolol (selective beta-1-antagonist, 50 mg/d), Ramipril (ACE-inhibitor, 2.5 mg/d) and placebo. There was a two-week wash-out phase between each of the four treatment phases. At the end of each treatment phase glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were measured by inulin and para-amino-hippuric acid (PAH) clearance. Proteinuria was determined in the course of a three-day collection period at the end of each treatment phase. During this period blood pressures were measured with a continuous 24-hour blood pressure monitor. RESULTS: Mean arterial blood pressure (MAP) was significantly reduced, compared with placebo, by all three antihypertensives (108 +/- 9 mm Hg with placebo, 98 +/- 12 mg Hg with atenolol, 101 +/- 11 mm Hg with celiprolol and 98 +/- 8 mm Hg with ramipril; P < 0.01). Celiprolol produced a significant rise In ERPF (322 +/- 109 ml/min with placebo, 391 +/- 110 ml/min with celiprolol: P < 0.05). GFR was slightly, but not significantly, reduced by celiprolol and atenolol. Filtration fraction remained unchanged with atenolol and celiprolol, while it was slightly, but not significantly, reduced with ramipril. Compared with the placebo, all three drugs significantly reduced proteinuria (P < 0.05): 1.8 +/- 1.3 g/24 h with placebo, 1.2 +/- 1.2 g/24 h with atenolol, 1.2 +/- 1.1 g/24 h with celiprolol and 1.4 +/- 1.4 g/24 h with ramipril. CONCLUSION: These data indicate that, in addition to ACE inhibitors, the new generation of beta-receptor blockers in particular, because of their vasodilator action, favourably influence proteinuria and renal blood flow in patients with CGN and arterial hypertension.

Adrenergic beta-Antagonists↗
PubMed1997

Use of DHEA in a patient with advanced prostate cancer: a case report and review.

Dehydroepiandrosterone (DHEA) is being evaluated in the basic science laboratories as a potential treatment for adenocarcinomas, with some initial promise for success. However DHEA can be metabolically converted to androgenic compounds, possessing unwanted side effects. A patient with advanced prostate cancer with progressive symptomatology was treated with DHEA after other treatment regimens failed. Many of his symptoms improved on DHEA therapy, but his cancer also flared dramatically during treatment. His previous hormonally unresponsive cancer subsequently responded transiently to third-line hormonal therapy with diethylstilbestrol (DES). Adrenal precursor molecules such as DHEA may have significant therapeutic benefits in a number of diseases of the elderly, however their utility may be limited by potential androgenic side effects including endocrine epithelial cell growth. The development of analogue compounds with less conversion to androgenic metabolites should be considered, as molecules such as DHEA are more widely tested and utilized clinically.

Aged↗
PubMed1997

Perifoveal capillary network in patients with acute central retinal vein occlusion.

PURPOSE: Reduction of visual acuity in patients with central retinal vein occlusion (CRVO) is often caused by macular edema and ischemia. The major causative factor for macular changes may be a disturbance in the macular microcirculation. The authors studied the perifoveal microcirculation in patients with central retinal vein occlusion to quantify the extent of circulatory deficiency in the macular circulation. METHODS: Twenty-four patients (8 men, 16 women) with recently diagnosed CRVO were included in this study. The following data were quantified: mean capillary blood velocity (CBV), foveal avascular zone (FAZ), and mean perifoveal intercapillary area (PIA). RESULTS: In patients with CRVO, the mean flow velocity was significantly reduced compared with healthy subjects (1.63 +/- 0.220 mm/sec vs. 2.89 +/- 0.41 mm/sec, P < 0.01). The FAZ and the mean PIA characterizing capillary density were significantly enlarged in CRVO (5548 +/- 1151 microm2 vs. 3872 +/- 529 microm2; P < 0.01). CONCLUSIONS: The present study demonstrates that CRVO not only led to a decrease in capillary blood velocities, but also to an enlargement of perifoveal intercapillary areas in early stages of the disease.

Acute Disease↗
PubMed1997

Eubacterial proteasomes.

Proteasomes are large, multisubunit proteases with highly conserved structures. The 26S proteasome of eukaryotes is an ATP-dependent enzyme of about 2 MDa, which acts as the central protease of the ubiquitin-dependent pathway of protein degradation. The core of the 26S complex is formed by the 20S proteasome, an ATP-independent, barrel-shaped protease of about 700 kDa, which has also been detected in archaebacteria and, more recently, in eubacteria. Currently, the distribution of 20S proteasomes in eubacteria appears limited to the actinomycetes, while most other eubacteria contain a related complex of simpler structure.

Amino Acid Sequence↗
PubMed1997

Imaging of retinal autofluorescence in patients with age-related macular degeneration.

BACKGROUND: Several studies have demonstrated an accumulation of autofluorescent materials in the retinal pigment epithelium (RPE) with increasing age. Histologic analysis revealed that lipofuscin is the most potential fluorescent substance in the aging RPE. Therefore, it has been speculated that lipofuscin precedes the presence of drusen and the development of age-related macular degeneration (ARMD). METHOD: A scanning laser ophthalmoscope was used to visualize autofluorescence in the fundus of patients with early ARMD. The digital recordings were analyzed offline with a digital image analyzing system. RESULTS: In 85 of 103 patients, focal areas of increased autofluorescence were visible. Areas of hyperpigmentation at the level of the RPE showed increased autofluorescence in all cases, whereas areas of depigmentation demonstrated decreased autofluorescence. CONCLUSION: Patients with ARMD demonstrated focal accumulation of fluorescent material most likely lipofuscin. Thus, the scanning laser technique combined with an image analyzing system may help to identify eyes at risk for developing exudative ARMD.

Aged↗
PubMed1997

Video fluorescein angiography of the anterior eye segment in severe eye burns.

PURPOSE: Severe eye burns often result in extensive necrosis of the conjunctiva and episcleral tissue. Video fluorescein angiography was performed to reveal the perfusion of the anterior eye segment after severe eye burns. METHODS: A scanning laser ophthalmoscope was used for anterior segment fluorescein angiography in 12 patients (14 eyes) with severe burns grade III-IV and in 7 healthy volunteers. RESULTS: Necrotic tissues occurred as non perfused areas and remained dark throughout the whole angiogram. In general, the borders from healthy to necrotic conjunctival tissue were sharply demarcated. Thus, the extent of scleral and limbal ischemia could be determined exactly. Injured vessels showed hyperfluorescence with late leakage. Damage of the subconjunctival tissue appeared as a deep weak fluorescence in the early angiography and exhibited patchy leakage in the late angiogram. CONCLUSIONS: Anterior segment angiography provides a basis for deciding the extent of surgical debridement of necrotic tissue in the acute phase of the burn. The determination of the extent of limbal and scleral ischemia may give useful information for early plastic-reconstructive procedures.

Adult↗
PubMed1997

Morphologic changes of the macula in a patient with Purtscher's retinopathy.

Purtscher's retinopathy is a rare complication after trauma to the chest or bone fractures. We report about a patient, which we examined 6 months after a serious car accident. Visual acuity was 20/20 in both eyes. Examination with the Amsler grid revealed a paracentral scotoma in the left eye. In the fluorescein angiography of the left eye performed with a scanning laser ophthalmoscope we found capillary dropout, which corresponded well to the scotoma. Measured by digital image analysis, the area of the foveal avascular zone was eccentrically enlarged by a factor of 4. The mean perifoveal intercapillary area was also enlarged in the corresponding quadrant. This reflects that focal capillary dropout may result in scotoma rather than in a decrease in visual acuity as reported in other diseases.

Adult↗
PubMed1997

Visceral responses to the social environment.

Twenty-five hundred years ago, Hippocrates, recognizing the impact of life experience on health wrote: "those things which one has been accustomed to for a long time, although worse than things to which one is not accustomed, usually give less disturbance" (Bruhn & Wolf 1978). Since Hippocrates, much evidence has emerged to suggest that social stability is conducive to health, while social change, especially rapid change, may predispose to illness. The idea that sensory information from ordinary life experiences contributes in a major way to shaping the activities of the brain, took root in the 18th century with Pierre Gassendi and John Locke. A mechanism whereby the vast numbers of neurons in the brain could be rapidly rearranged and organized to respond to a host of different external stimuli emerged from the work of Santiago Ramon y Cajal who discovered the axonal growth cone and its capacity to elongate and guide an axon a considerable distance to a target dendrite (Cajal 1890). Thereby, with very rapid shifts in attention and perception, a wide range of responses, emotional, and physiological can be elicited. With this and other evidence at hand that the intracranial regulatory mechanisms can reorganize in response to environmental change including social change, we undertook a 30 year (1962-1992) prospective study of the effects of social patterns on health in Roseto, a closely knit Italian-American incorporated town in Pennsylvania. It was settled in 1882 by Italians from Roseto val Fortore, a town in southern Italy near the Adriatic Sea. We found a sharp increase in myocardial infarction among Rosetans when long established cohesive social patterns began to weaken and be replaced by more egocentric attitudes.

Adult↗