[On splitting N-sorboyl-amino acids by enzymes of the digestive tract. Preliminary report].
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to K Lang.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Transcatheter closure of atrial septal defects (ASDs) has become a routine procedure in many countries of the world. It spares many patients cardiac surgery and has proven efficacy in long-term studies. Device improvements have resulted in a continuous reduction of complications and of residual shunt frequency. ASD closure devices are also used for transcatheter closure of patent foramen ovale (PFO) for prevention of paradoxical embolism. In the past few years, there has been increasing interest in developing devices specifically designed for PFO closure. Although transcatheter closure of ASDs is well established, interventional closure of the left atrial appendage is in its development stage. Closure of the left atrial appendage is designed to reduce the risk of stroke in patients with atrial fibrillation in whom anticoagulation with Warfarin-type drugs is contraindicated. This article describes the latest developments in catheter closure of PFO and the left atrial appendage.
Rates of protein folding reactions vary considerably. Some denatured proteins regain the native conformation within milliseconds or seconds, whereas others refold very slowly in the time range of minutes or hours. Varying folding rates are observed not only for different proteins, but can also be detected for single polypeptide species. This originates from the co-existence of fast- and slow-folding forms of the unfolded protein, which regain the native state with different rates. The proline hypothesis provides a plausible explanation for this heterogeneity. It assumes that the slow-folding molecules possess non-native isomers of peptide bonds between proline and another residue, and that crucial steps in the refolding of the slow-folding molecules are limited in rate by the slow reisomerization of such incorrect proline peptide bonds. Recently the enzyme peptidyl-prolyl cis-trans isomerase (PPIase) was discovered and purified from pig kidney. It catalyses efficiently the cis in equilibrium trans isomerization of proline imidic peptide bonds in oligopeptides. Here we show that it also catalyses slow steps in the refolding of a number of proteins of which fast- and slow-folding species have been observed and where it was suggested that proline isomerization was involved in slow refolding. The efficiency of catalysis depends on the accessibility for the isomerase of the particular proline peptide bonds in the refolding protein chain.
The objective of this study was to estimate the direct medical cost of Alzheimer disease (AD) and related dementia to the Georgia Medicaid program. A retrospective, cross-sectional, matched control group design was used. AD cases 50 years of age and older were identified by using International Classification of Diseases (9th edition, Clinical Modification) diagnosis codes from 1994 Georgia Medicaid administrative claims files. For every case, three age- and gender-matched non-AD controls were selected. Differences in average recipient Medicaid expenditures between cases and controls were estimated using weighted least squares regression analysis, adjusting for age, gender, race, Charlson comorbidity index, Medicare eligibility, and months of Medicaid eligibility. A total of 8,671 AD cases were identified (prevalence, 4.4%). The average adjusted annual Medicaid expenditure per AD recipient was $14,492 (U.S.). The net (i.e., excess) average annual Medicaid cost per AD recipient (i.e., the difference in adjusted mean expenditures between cases and controls) was estimated to be approximately $8,200. Excessive nursing home expenditures accounted for most of the additional cost of treating dementia (> 85%), although inpatient hospital, physician, outpatient, and prescription drug expenditures also were higher among patients with AD. Based on these estimates, Georgia Medicaid is projected to spend almost $70 million annually for AD and related dementia. The excessive cost attributable to AD poses a significant burden to the Georgia Medicaid program.
Lorcainide is a new antiarrhythmic agent which effectively suppresses ventricular premature contractions. Its electrophysiological actions were studied in 15 cardiac patients with and without cardiac conduction abnormalities. In a dose of 2 mg/kg body weight, lorcainide decreased the sinus cycle length (SCL) and increased the corrected sinus node recovery time. The intra-atrial, atrioventricular (AV), and intraventricular conduction times were prolonged. A third-degree AV block developed in 2 patients with pre-existing conduction abnormalities. QRS widening showed that intramyocardial conduction was also affected. The effective refractory period of the atrioventricular node (ERP-AVN) was shortened, whereas the effect on the functional refractory period of the AVN was variable. The decrease in SCL and ERP-AVN may be due to a possible anticholinergic effect of the drug. The accessory pathway was blocked in 3 patients with a Wolff-Parkinson-White syndrome. The ERP of the ventricle was slightly prolonged. The electrophysiological profile of the drug, i.e., slowing of conduction velocity throughout the heart combined with shortening of SCL and ERP-AVN, differs from other antiarrhythmic agents.
Porphyria cutanea tarda (PCT) is the most frequent form of porphyria. The underlying enzymatic defect in PCT is a reduced activity of the enzyme uroporphyrinogen decarboxylase (Uro-D). Four different types of Uro-D disturbances are known. Pseudoporphyrias such as porphyria cutanea uraemica or drug-induced PCT-like skin symptoms are distinguished from PCT. Porphyrinogens such as estrogens or alcohol, or other inducers of P450 isoenzymes provoke PCT. Polymorphisms of P450 isoenzymes, iron overload and infection with hepatitis C virus play an important role in the etiopathogenesis of disease manifestation. Dominant clinical symptoms are bullae, increased cutaneous vulnerability, hypertrichosis and elastosis. Biochemically, total porphyrin levels in urine are increased with a predominance of uroporphyrin and heptacarboxylic porphyrin. Isocoproporphyrin is demonstrable in feces. Best therapeutic strategies are the oral administration of chloroquine 125 mg twice a week and repetitive bloodlettings or the combination of both.
Congenital erythropoietic porphyria (CEP) is one of the rarest autosomal-recessive disorders of the porphyrin metabolism caused by the homozygous defect of uroporphyrinogen III cosynthase. High amounts of uroporphyrin I accumulate in all cells and tissues, reflected by an increased erythrocyte porphyrin concentration and excretion of high porphyrin amounts in urine and feces. Dermal deposits of uroporphyrin frequently induce a dramatic phototoxic oxygen-dependent skin damage with extensive ulcerations and mutilations. Splenomegaly and hemolytic anemia are typical internal symptoms. Skeletal changes such as osteolysis and calcifications are frequent. Up to date 130 cases of CEP have been published. Splenectomy and erythrocyte transfusions showed some beneficial effect. Bone marrow transplantation was performed in 3 patients and stem cell transplantation in 1. The best therapy is the avoidance of sunlight. We give a report on our latest cases of CEP.
The topical application of delta-aminolevulinic acid (ALA) induces porphyrin formation in the skin, preferentially in tumor tissues. Irradiation of the porphyrin-enriched tumor tissue with Wood's light leads to emission of a brick-red fluorescence. This principle may be used as a diagnostic procedure which may be termed photodynamic diagnosis (PDD). In ALA-PDD, tumors and precancerous lesions of the skin reveal a homogeneous, intensive red fluorescence. Psoriatic lesions also show a strong but inhomogeneous porphyrin fluorescence. ALA-induced porphyrin fluorescence in preoperative planning is a valuable method to determine the peripheral borders of a given tumor. The histopathological extensions of the tumors correlate well with the borders detected by the tumor-specific fluorescence. The main indications of PDD are the delineation of clinically ill-defined skin tumors and the control of the efficacy of other tumor therapies. Photodynamic therapy (PDT) utilizes exogenously applied or endogenously formed photosensitizers and their activation by light to induce cell death via formation of singlet oxygen and other free radicals. PDT is highly efficient in the treatment of solar keratoses and superficial basal cell carcinomas. Initial squamous cell carcinomas also show good response to ALA-PDT. During the last decade, numerous studies on PDT for dermatologic diseases were published, the more important ones are reviewed here.
The efficacy of dihydropyridine calcium channel blockers for treating hypertension appears to be similar, but a variety of factors, including patient characteristics, tolerability and pharmacokinetic properties, may influence treatment adherence and outcome. We aimed to evaluate treatment adherence in clinical practice among older hypertensive adults (50+ years) prescribed amlodipine or felodipine for the first time as part of the California Medicaid (Medi-Cal) program. We used a retrospective, matched, cohort-analysis design. Over 1 year, patients prescribed amlodipine were 21% less likely to discontinue study treatment than those prescribed felodipine. Discontinuation tended to occur early, with 20% and 30% of amlodipine and felodipine patients, respectively, discontinuing treatment after one prescription. A non-significant difference in favour of amlodipine was demonstrated for anti-anginal medication use among patients taking these drugs at baseline. This study suggests that use of amlodipine may be associated with improved adherence, compared with felodipine, among older out-patients in the Medi-Cal program.
Premature termination of inpatient psychotherapy can have multiple, mostly negative, effects for patients, therapists, clinics, insurance companies, and employers, but research regarding inpatient settings is still deficient. The analysis of two sets of data of four different rehabilitation clinics from two different hospital companies (2699 and 2215 patients, respectively), aimed at possible predictors and outcomes of premature termination. We found ratios of premature termination of 8.3% and 14.7%, respectively. Especially young patients under 30 years of age and patients with eating and personality disorders were more likely to terminate inpatient treatment prematurely. Treatment outcome as rated by therapists was in significantly fewer cases among premature terminators than among successful terminators improved. The results seem to indicate, that assignment to inpatient psychotherapy can be optimized. For a better understanding of the process of premature termination more theory guided prospective and followup studies are necessary.
The mortality of low birth weight infants is twenty times higher than that of mature infants (up to 2500 g). The influences of several social parameters to the birth weight of liveborn children are examined. All liveborn children from 1983 to 1986 in the formerly district of Gera in Thuringia are counted. Risks concerning an increased rate of premature birth are multiparity, higher birth order, maternal age below 19 and over 30 years, unskilled mothers of during their vocational training, unwed mothers and mothers working in trade factories. These mothers need a more intensive care during their pregnancy. The efforts have to be intensified to minimize risks specific for occupation to pregnant women.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.