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R Schmidt

Publications and source records attributed to R Schmidt.

At least 235 records · Page 13Linked to original sources
PubMed1998

[Repositioning social work with the elderly? Effect of competitive elements and new guidance models on the profile of a profession].

The article discusses changes in the context within which the social professions are exercised. The chances for a refinancing of social work and indeed its very locations change in line with the transition to new steering elements in the social body and the new implementation of competitive elements in the realm of public law. With the economising of the social sphere social work is questioned under economic aspects. Simultaneously it gains normative significance. This is true with regard to standards for the quality of services and institutions, and further in the context of the discussion concerning the revitalisation of local social policy for the elderly. Precisely the economising of the social sphere raises the question whether the municipalities may be excused from their responsibility to form, preserve and support the obligations of social work with the elderly. This article denies this.

Aged↗
PubMed1998

Adenocarcinoma of the uterine cervix metastatic to lymph nodes.

OBJECTIVE: We set out to evaluate the prognostic factors in cervical adenocarcinoma metastatic to lymph nodes. STUDY DESIGN: We performed a retrospective review of 40 patients with cervical adenocarcinoma and lymph node metastasis from 1976 to 1996. RESULTS: Thirty-four patients had adenocarcinoma, and six had adenosquamous carcinoma. Median survival was 50 months. The median survival for patients with stage I disease was 69 months. Stage at diagnosis, treatment with radical hysterectomy, and receiving adjuvant therapy were associated with prolonged survival. A trend toward improved survival was noted with the use of concurrent radiation and chemotherapy as an adjuvant therapy. CONCLUSIONS: Adenocarcinoma metastatic to the lymph nodes does not have a uniformly poor prognosis, especially with early-stage disease. Improved survival was observed with the use of adjuvant therapy, specifically the use of combined chemotherapy and radiation after radical hysterectomy. The optimal therapy in this setting is yet to be determined.

Adenocarcinoma↗
PubMed1998

Selectins as new targets for immunoliposome-mediated drug delivery. A potential way of anti-inflammatory therapy.

Endothelial cell adhesion molecules, which are expressed in response to inflammatory signals to mediate recruitment of leukocytes to sites of inflammation, appear to be excellent targets for drug delivery systems to open new perspectives of antiinflammatory therapies. In this study we describe the preparation and characterization of antibody-coupled liposomes (immunoliposomes) as directed against endothelial (E)-selectins. We have examined the factors affecting the covalent coupling of antibodies to the membrane anchor N-glutaryl-phosphatidylethanolamine via amide bound and have compared them to other coupling procedures. The target sensitivity has been demonstrated in a cell-containing in-vitro model, where liposome binding to selectins under either static, or simulated blood flow conditions was illustrated by using fluorescence microscopical means. It could be shown that even under shear force conditions liposomes selectively accumulate at selectin-containing cells when a specific lipid composition and a certain balance in the lipid/antibody ratio was maintained. Furthermore, the need for polyethylene glycol-derived lipids to sterically stabilize the liposomes for preventing unspecific liposome attachment to cells has been demonstrated.

Animals↗
PubMed1998

Protein A immunoadsorption (i.a.) in renal transplantation patients with vascular rejection.

Vascular rejection after renal transplantation is connected with a higher frequency of allograft dysfunction or graft loss. Plasmapheresis as an adjunctive therapy in the treatment of humoral mediated acute graft rejection was compared with protein A immunoadsorption. Eleven patients with acute graft rejection and high titers of cytotoxic HLA-Ab and/or signs of vascular rejection at graft biopsy (performed in 9 patients) have been treated. Six of them have a stable graft function, the longest graft survival until now is 41 months, four are back on haemodialysis and one patient died from CMV-pneumonia with a stable graft function 9 months after transplantation. We conclude that IA is a useful adjunctive therapy in the treatment of vascular rejection after renal transplantation. Further investigations are necessary to optimize criteria for inclusion.

Endothelium, Vascular↗
PubMed1998

Integrin alpha5beta1: a potent inhibitor of experimental lung metastasis.

The integrin alpha5beta1 seems to be the most relevant receptor of tumor cells for binding to fibronectin. Although numerous studies suggest a role of tumor cell fibronectin interaction in tumor metastasis, differential integrin expression on tumor cells has, however, not been correlated with metastatic capabilities. We addressed this question by transfection of the integrin alpha5beta1 cDNA into HT-29 human colon carcinoma cells which led to de novo expression of functional integrin alpha5beta1. Similar to other reports, expression of the integrin alpha5beta1 in HT-29 tumor cells exerted an inhibitory action on cell proliferation as indicated in our study by formation of fewer colonies in soft agar. The tumor growth inhibitory property of the integrin alpha5beta1 was also shown by reduction of subcutaneous xenograft growth in nude mice to approximately 50% of that of control transfectants. For the first time, we found that several clones of integrin alpha5 subunit transfectants displayed dramatically reduced formation of lung colonies and cutaneous metastasis after intravenous injection into nude mice. While most animals inoculated with control transfectant cells formed macroscopically visible lung colonies ranging from 12.6 +/- 2.6 to 22.0 +/- 6.6 (mean colony number +/- SEM), mice inoculated with HT-29 cell clones expressing the integrin alpha5beta1 were almost completely free of lung colonies (ranging from 0.0 +/- 0 to 0.2 +/- 0.1). Our results imply that integrin alpha5beta1 expression inhibits circulating tumor cells in pursuing late steps of the metastatic process as represented by the artificial metastasis (lung colonisation) model.

Animals↗
PubMed1998

Expression of the tumor suppressor gene product p16INK4 in benign and malignant melanocytic lesions.

The gene MTS1 encodes p16INK4, an inhibitor of cyclin-dependent kinase 4, and is frequently deleted, mutated, or silenced by promoter methylation in melanoma cells and in the germline of familial melanoma patients. Although MTS1 may thus be the candidate melanoma suppressor gene that maps to chromosome 9p21, it is not clear how dysfunction at that locus temporally relates to melanoma progression. To further test its role in sporadic melanoma, the expression of p16INK4-protein and -mRNA was characterized in melanomas and melanocytic nevi by immunocytochemistry and in situ reverse transcriptase-polymerase chain reaction. Histologic tissue sections were immunolabeled with anti-p16INK4 antibody for 108 melanocytic lesions, including common and atypical nevi, in situ melanomas, primary invasive melanomas, and metastatic tumors. A subset of the lesions was analyzed for expression of p16INK4-mRNA, employing forward and reverse intron-bridging primers for reverse transcriptase-polymerase chain reaction amplification of the transcript corresponding to exons 1 and 2 of MTS1. Strong immunolabeling was detected in the melanocytes of common nevi and of nevi with architectural disorder and cytologic atypia. By digital image analysis, in contrast, labeling intensity decreased significantly and progressively in the melanocytes of in situ, invasive, and metastatic melanomas. Results from the in situ reverse transcriptase-polymerase chain reaction analysis were confirmatory, showing a strong signal in the melanocytic nevi but progressive signal attenuation with increasing stage of melanoma. These data indicate correlation between gradual loss of expression of the MTS1 locus and progression of melanoma, further supporting an emerging role for the gene in the malignant transformation of melanocytes. The failure to demonstrate reduced expression in nevi suggests either that these lesions are not an early stage in melanoma development, in contrast to prevailing assumptions, or that loss of p16INK4 function is not an initiating event in melanocyte transformation.

Antibodies, Monoclonal↗
PubMed1998

Renal failure in giant cell vasculitis.

A 59-year-old white woman with temporal arteritis developed progressive renal failure. Renal biopsy results showed focal and segmental necrotizing glomerulonephritis; furthermore, giant cells were present in the destructed vessel walls. Immunosuppressive therapy did not prevent terminal renal failure. This case shows that renal involvement may be a feature of temporal arteritis.

Female↗
PubMed1998

The male-determining activity on the Y chromosome of the housefly (Musca domestica L.) consists of separable elements.

In the common housefly, the presence or absence of a male-determining factor, M, is responsible for sex determination. In different strains, M has been found on the Y, on the X, or on any of the five autosomes. By analyzing a Y-autosomal translocation and a ring-shaped, truncated Y chromosome, we could show that M on the Y consists of at least two regions with M activity: One of them can be assigned to the short arm of the Y chromosome (MYS), which is largely C-banding negative, the other region lies on the C-banding positive long arm of the Y, including the centromeric part (MYL). Each region alone behaves as a hypomorphic M factor, causing many carriers to develop as intersexes of the mosaic type instead of as males. When introduced into the female germ line by transplantation of progenitor germ cells (pole cells), the MYS shows an almost complete maternal effect that predetermines 96% of the genotypic female (NoM) animals to develop as males. In contrast, the MYL has largely lost its maternal effect, and most of the NoM animals develop as females. Increasing the amount of product made by either of the two hypomorphic M factors (by combining the MYS and MYL or two MYS) leads to complete male development in almost every case. We thus assume that the Y chromosome carries at least two copies of M, and that these are functionally equivalent.

Animals↗
PubMed1998

Plasma antioxidants and cognitive performance in middle-aged and older adults: results of the Austrian Stroke Prevention Study.

OBJECTIVES: To study the association between cognitive status and plasma concentrations of various antioxidants in middle-aged and older individuals without neuropsychiatric disease. DESIGN: Evaluation of cross-sectional data from a cohort study. SETTING: The Austrian Stroke Prevention Study. PARTICIPANTS: A total of 1769 subjects aged 50 to 75 years, with no history or signs of neuropsychiatric disease, selected randomly from the community register. MEASUREMENTS: The score on the Mattis Dementia Rating Scale (MDRS) was dichotomized according to age-and education-specific lowest quartile cut-off points. Reversed-phase high performance liquid chromatography measurements of the plasma concentrations of lutein/zeaxanthin, cryptoxanthin, canthaxanthin, lycopene, alpha-carotene, beta-carotene, retinol, gamma-tocopherol, alpha-tocopherol, and ascorbate were measured. RESULTS: Individuals with MDRS results below the lowest quartile cut-off point had lower levels of beta-carotene and alpha-tocopherol than their counterparts with test performance above this limit (0.44+/-.33 micromol/L vs 0.51+/-.48 micromol/L, P < .001; and 29.50+/-7.98 micromol/L vs 30.93+/-11.10 micromol/L, P < .001, respectively). Only alphatocopherol remained significantly associated with cognitive functioning when logistic regression analysis was used to adjust for possible confounders including age, sex, month of blood sampling, years of education, smoking, lipid status, and major risk factors for stroke (P = .019). CONCLUSION: These observations are compatible with the view that some dietary antioxidants may protect against cognitive impairment in older people.

Age Factors↗
PubMed1998

Cariostatic effects of a xylitol/NaF dentifrice in vivo.

Xylitol has been shown to reduce plaque acids, but its topical cariostatic effect has been equivocal. The purpose of the studies reported here was to optimise the xylitol/NaF combination in dentifrices for an improved anticaries activity. In the first study, the combination of 10 per cent xylitol with 1100 ppm F (NaF), 1100 ppm F (NaF), and placebo dentifrices were tested in a rat caries model to assess the cariostatic effect. The combination was significantly more effective than fluoride by itself (P = 0.05). The xylitol/NaF combination provided significantly more remineralisation of dentine than fluoride by itself. Collectively, results of these investigations confirm the improved anticaries effectiveness of the xylitol/NaF combination in a variety of animal and intra-oral models. A three-year clinical study confirmed these findings.

Acids↗
PubMed1998

Innervation territories of single sympathetic C fibers in human skin.

Microneurography techniques were used to record action potentials from unmyelinated nerve fibers (C fibers) in the cutaneous fascicles of the peroneal nerve in healthy volunteers. C units were identified by their long latency responses to electrical stimulation of their terminals in the skin. Their responsiveness to mechanical or heat stimuli applied to the skin or to sympathetic reflex provocation tests was determined by transient slowing of conduction velocity following activation (marking technique). In a sample of 381 C units, 59 were unresponsive to mechanical and thermal stimulation of their endings, but responded to sympathetic reflex provocation tests, e.g., arousal or deep inspiration. They were classified as sympathetic efferent units. On average, conduction velocities of sympathetic units were lower (0.78 +/- 0.12 m/s, mean +/- SD) than those of mechano-heat (CMH) or mechanoresponsive (CM) afferent C units (0.91 +/- 0.14 m/s). Endings of most of the sympathetic units were located in the skin of toes or in the foot dorsum. Innervation territories of 16 sympathetic units were mapped by means of conditioning transcutaneous electrical stimuli. Twelve units had one continuous skin territory, whereas two units had two and two other units had three and five separate territories, respectively. The mean innervated area was 128 mm2 (range: 24-350 mm2). Innervation territories of sympathetic units were of approximately the same size in different skin regions on the lower leg, foot, or toes. Based on responses to whole body cooling and warming, two units were tentatively classified as vasoconstrictor and sudomotor units, respectively. Eleven units were tested for responsiveness to iontophoresis of acetylcholine in their innervation territories. In five of them, activity was induced that was not due to central reflex activity but instead due to antidromic activation from the peripheral terminals. Iontophoresis of saline or histamine was ineffective. These findings confirm the existence of excitatory cholinergic receptors in the terminal membrane of some sympathetic units, possibly sudomotors.

Acetylcholine↗
PubMed1998

Pathophysiologic mechanisms in the development of age-related white matter changes of the brain.

Magnetic resonance imaging (MRI) has dramatically enhanced our capability of detecting age-related changes of the brain even before they become clinically apparent. Among those are preferentially alterations of the white matter in periventricular, deep and subcortical locations which display high signal intensity on both proton density- and T2-weighted images. Correlative histopathologic findings show hyperintense periventricular capping of the frontal horns to reflect predominantly a specific anatomic situation characterized by loosely arranged fine-fiber tracts with low myelin and high extracellular fluid content. A smooth halo of periventricular hyperintensity has been linked to disruption of the ependymal lining with subependymal gliosis and concomitant loss of myelin. In contrast, punctate, early confluent and confluent hyperintensities in the deep and subcortical white matter as well as irregular periventricular hyperintensity appear to be of vascular origin. Punctate lesions tend to correspond to a perivascular reduction in myelin content with atrophy of the neuropil and seem to constitute a negligible extent of tissue damage from low permeability through thickened arteriolar walls. Early confluent and confluent hyperintensities, however, indicate more extensive ischemic damage consistent with advanced microangiopathy.

Aging↗
PubMed1998

Beta-fibrinogen gene polymorphism (C148-->T) is associated with carotid atherosclerosis: results of the Austrian Stroke Prevention Study.

Polymorphisms at the beta-fibrinogen locus have been shown to be associated with plasma concentration of fibrinogen and coronary heart disease. The effect of the genetic heterogeneity of fibrinogen on carotid atherosclerosis has not been determined so far. We examined the influence of the C148 --> T polymorphism on carotid disease in a large cohort of middle-aged to elderly subjects without evidence of neuropsychiatric disease. This polymorphism is located close to the consensus sequence of the interleukin-6 element and may represent a functional sequence variant. The genotype of 399 randomly selected, neurologically asymptomatic individuals, aged 45 to 75 years, was determined by denaturing gradient gel electrophoresis. Carotid atherosclerosis was assessed by color-coded duplex scanning and was graded on a five-point scale ranging from 0 (=normal) to 5 (=complete luminal obstruction). The C/C, C/T, and T/T genotypes were noted in 226 (56.6%), 148 (37.1 %), and 25 (6.3%) individuals, respectively. The T/T genotype group demonstrated higher grades of carotid atherosclerosis than did the C/C and C/T genotypes (P=.003). Logistic regression analysis created a model of independent predictors of carotid atherosclerosis that included apolipoprotein B (odds ratio [OR], 1.17/10 mg/dL), age (OR, 2.46/10 years), lifetime tobacco consumption (OR, 1.03/1000 g), presence of the beta-fibrinogen promoter T/T genotype (OR, 6.17), plasma fibrinogen concentration (OR, 1.05/10 mg/dL), and cardiac disease (OR, 1.80). These data suggest that the beta-fibrinogen promoter T/T148 genotype represents a genetic risk factor for carotid atherosclerosis in the middle-aged to elderly.

Aged↗
PubMed1998

Paraoxonase PON1 polymorphism leu-Met54 is associated with carotid atherosclerosis: results of the Austrian Stroke Prevention Study.

BACKGROUND AND PURPOSE: Genetic polymorphism at the paraoxonase locus is associated with serum concentration and activity of paraoxonase and with increased risk for coronary heart disease. Two frequent polymorphisms present at the paraoxonase gene are the methionine (M allele) leucine (L allele) interchange at position 54 and the arginine (B allele) glutamine (A allele) interchange at position 191. This is the first study to determine the effect of these polymorphisms on carotid atherosclerosis. METHODS: The paraoxonase genotypes at positions 54 and 191 of 316 randomly selected individuals aged 44 to 75 years were determined by polymerase chain reaction-based restriction enzyme digestion. Carotid atherosclerosis was assessed by color-coded Duplex scanning and was graded on a 5-point scale ranging from 0 (normal) to 5 (complete luminal obstruction). RESULTS: The LL, LM, and MM genotypes at position 54 were noted in 137 (43.4%), 132 (41.8%), and 47 (14.9%) subjects; the AA, AB, and BB genotypes at position 191 occurred in 172 (54.4%), 124 (39.2%), and 20 (6.3%) individuals. The LL genotype was significantly associated with the presence and severity of carotid disease (P=0.022), whereas the 191 polymorphism had no effect. Logistic regression analysis with age and sex forced into the model demonstrated plasma fibrinogen (odds ratio [OR], 1.005 per mg/dL), LDL cholesterol (OR, 1.01 per mg/dL), cardiac disease (OR, 1.75), and the paraoxonase LL genotype to be significant predictors of carotid atherosclerosis. The ORs for the associations with age and sex were 1.09 (P=0.0003) and 1.66 (P=0.052) per year. CONCLUSIONS: These data suggest that the paraoxonase LL genotype may represent a genetic risk factor for carotid atherosclerosis.

Aged↗
PubMed1998

Focusing on resistance development in a case based teleconsultation system for antibiotics therapy advice.

In this paper, we describe an approach to support physicians when they select a calculated antibiotic therapy for intensive care patients who have developed an infection as an additional complication. As advice is needed quickly and the pathogen is not yet known, we use an expected pathogen spectrum based on medical background knowledge and known resistances, which both will be adapted to the results of the laboratory. Case-Based Reasoning retrieval methods provide the advice for similar previous patients. Their solutions are adapted to be applicable to the new medical situation of the current patient. Furthermore, we present the recent resistance developments of the antibiotics to the physician.

Anti-Bacterial Agents↗
PubMed1998

Prognoses of multiparametric medical time courses applied to kidney function assessments.

In this paper, we describe an approach to utilize Case-Based Reasoning methods for trend prognoses for the monitoring of the kidney function in an Intensive Care Unit (ICU) setting. Since using conventional methods for reasoning over time does not fit for course predictions with poor medical knowledge of typical course patterns, we have developed abstraction methods suitable for integration into our Case-Based Reasoning system ICONS. These methods combine medical experience with prognoses of multiparametric courses. On the ICU, the monitoring system NIMON provides a daily report based on current measured and calculated kidney function parameters. We subsequently generate course-characteristic trend descriptions of the renal function over the course of time. Using Case-Based Reasoning retrieval methods, we search in the case base for courses similar to the current trend descriptions. Finally, we present the current course together with similar courses as comparisons and as possible prognoses to the user. We applied Case-Based Reasoning methods in a domain which seemed reserved for statistical methods and conventional temporal reasoning.

Artificial Intelligence↗
PubMed1998

Different utilization of neutral lipids by Malassezia furfur and Malassezia sympodialis.

In recent years, the genus Malassezia has been expanded based on molecular data; in addition to M. furfur and M. pachydermatis, five new species (M. sympodialis, M. globosa, M. obtusa, M. restricta, M. slooffiae) have been described. Apart from their lipid dependence, little is known about the metabolism and nutritional requirements of these new species. Defined inocula of Malassezia reference strains were cultured on selective agar for pathogenic fungi which was overlaid with olive oil. Samples of the olive oil overlay were taken at regular intervals and the lipid fractions were analysed by high performance thin layer chromatography. Depending on the time of incubation and the number of cells, M. sympodialis and the other recently described species produced a significant increase in free fatty acids. In addition, a band of an apolar substance was identified as a mixture of fatty acid ethyl esters. While showing growth, strains of M. furfur produced only small amounts of ethyl esters and free fatty acids. The growth kinetics of M. furfur and M. sympodialis were also different: for M. sympodialis, a clear lag phase was observed, possibly indicating the necessity of extracellular hydrolysis of the triglycerides. The significance of the synthesis of ethyl esters could not be clarified. For routine differentiation, this metabolic difference is only of limited usefulness because slight contamination of M. furfur strains with other lipophilic Malassezia species may lead to misinterpretation due to the high metabolic activity. These metabolic differences might be important in the pathogenesis of Malassezia infections.

Agar↗