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Biomedical subjects

H Ziegler

Publications and source records attributed to H Ziegler.

At least 91 records · Page 5Linked to original sources
PubMed1985

Degradation of phenolic compounds by the yeast Candida tropicalis HP 15. I. Physiology of growth and substrate utilization.

The yeast Candida tropicalis HP 15 was able to utilize phenol up to concentrations of 2.5 g/l as a sole carbon and energy source. Phenol was metabolized via the beta-ketoadipate pathway by an inducible enzyme system. Besides phenol, resorcinol, quinol, hydroxyquinol, catechol, and to a lesser extend 4-chlorocatechol, protocatechuate, p-cresol, m-chlorophenol, and p-chlorophenol were metabolized by the yeast. A total of 30 aromatic compounds were tested as substrates.

Adipates↗
PubMed1985

Comparison of histology and immunohistochemistry with thyroglobulin serum levels and radioiodine uptake in recurrences and metastases of differentiated thyroid carcinomas.

The importance of lightmicroscopical and immunohistochemical features of 38 recurrent differentiated thyroid carcinomas (27 papillary carcinomas (PC), 11 follicular carcinomas (FC] for post-operative serum thyroglobulin (TG) concentrations was analysed in regard to pre-operative serum TG levels with tumour type, histological and cytological differentiation, volume fraction of TG synthesizing tumour cells (TG immunohistomorphometry), tumour volume and radioiodine uptake (RIU). Serum TG concentrations increased with tumour size and the number of TG synthesizing tumour cells (r = 0.5). PC and FC did not differ in their volume proportions of TG synthesizing tumour cells, while TG serum levels in FC significantly exceeded those of PC of similar size. The low TG serum levels found in PC might be explained by a specific defect in thyroglobulin secretion. Carcinomas with partial or total cytologic metaplasia (e.g. oxyphilic carcinomas) had low volume proportions of TG synthesizing cells and low serum TG levels. Thirteen of the 38 differentiated carcinomas (34.2%) showed both high TG serum levels and positive RIU, 17 (44.7%) disclosed only elevated TG serum levels and 6 (15.8%) a positive RIU. In two cases (5.3%) TG serum levels were not elevated and RIU's were negative. TG immunostaining was positive in all 38 cases. In summary, TG serum levels depend on the following morphologic factors in differentiated thyroid carcinomas: 1) Number of TG synthesizing tumour cells, 2) Mode of TG secretion and 3) Cytological differentiation of the tumour cells. Serum TG levels did not predict total body iodine scan.

Adolescent↗
PubMed1985

[Recurrent ileus in jejunal diverticulitis].

Jejunal diverticula are in most cases acquired lesions of the intestinal wall, which are caused by abnormalities of smooth muscle or myenteric plexus. They may lead to more complications than previously expected. The described patient developed an acute abdomen 8 years after an ileus due to jejunal diverticulitis with enterolith formation and resection of two jejunal diverticula. Immediate laparotomy had demonstrated again an ileus, partly induced mechanically by an obstruction due to 2 enteroliths, partly induced paralytically due to local peritonitis. The surgical significance of jejunal diverticula is discussed.

Cholelithiasis↗
PubMed1984

[Surgery for stomach cancer in patients over 70].

Among a total of 1038 operations for early and advanced gastric cancer, 257 patients were older than 70 years. The resection rate in this group was 64.2%, 95 subtotal and 70 total gastrectomies were performed. Postoperative complications were caused primarily by concomitant respiratory and cardiac diseases, whereas the overall operative mortality amounted to 16.9%. Depending on the stage of tumour development a 5-year survival rate of 17.7% could be obtained. This rate increased to 27.2% after subtotal or total gastrectomies. The choice of surgical procedures for gastric cancer does not show any principal differences between young and old persons; thus, the use of individual and liberal criteria for total gastrectomy can be justified even in the aged.

Adult↗
PubMed1983

[Contribution of the Saarland Cancer Register to the epidemiology of skin tumors].

2363 epitheliomas and 450 melanomas were reported to the Saarland Cancer Register between 1967 and 1978. We evaluated these 2813 cases and established the following ratio: Basal cell epithelioma: squamous cell carcinoma: melanoma = 63.4%:24%:12.5%: or 5:2:1. Bowen's disease, Bowen carcinoma and adenocarcinoma constitute a rarity. 80% of the basal cell epitheliomas, and 76% of the squamous cell carcinomas were localized on face, neck and head, the sites of predilection being the eyelids with basal cell epitheliomas, the lower lip with squamous cell carcinomas, and the ears with both epitheliomas in men. While no significant sex-related prevalence could be established for basal cell carcinoma, 56.5% of the squamous cell carcinoma were found in men, and 43.5% in women. The 450 melanoma-cases revealed a preference for women, the ratio of men:women turned out to be 1:1.58.

Adenocarcinoma↗
PubMed1983

[Resection of juxtahilar bile duct carcinoma instead of palliative drainage of the biliary tract].

Instead of the widely recommended approach of treating hilar carcinoma of the bile ducts by simple palliative biliary drainage, step by step a policy of primarily aiming at resection for cure has been adopted. So far in 11 out of 22 patients excision of the tumor was possible by resection of the hepatic duct confluence; in 4 cases a left hemihepatectomy had to be added because of carcinomatous infiltration of the left liver lobe or the left hepatic artery. The multiple bile duct openings remaining after resection of such tumors were reconstructed to one or two orifices and a bi- or unilateral Roux-en-Y cholangiojejunal anastomosis performed. In further 3 cases orthotopic liver transplantation was necessary to remove all visibly infiltrated tissue. In the remaining 8 patients because of documented extrahepatic carcinomatous spread palliative biliary drainage by a percutaneous U-tube or an endoprothesis was indeed considered the only reasonable measure. Despite the relatively high resectional rate of 60% and the extensive operations performed early mortality was confined to one patient who succumbed to septic endocarditis 6 weeks after the operation. At present the longest postoperative interval without recurrence amounts to 3 1/2 years. Nine patients free of recurrent disease are in perfect health; in 3 patients in whom a recurrence was observed after 1/2, 1 1/2 and 2 years meanwhile palliation was perfect. In contrast all patients with unresected tumors but carrying draining stents suffered from cholangitis and after 1 1/2 years all but one had died. In conclusion resectional therapy for hilar carcinoma seems possible with acceptable risk. Since only resection can provide potential cure and also palliation was better than that achieved by draining tubes a more aggressive attitude to the treatment of these lesions is advocated from our experience.

Adenocarcinoma↗
PubMed1982

Protein-catalyzed phospholipid exchange in bilayer vesicles determined by flow cytometry and electron microscopy.

The protein-induced lipid transfer between phosphatidylcholine vesicles was investigated. Measurements of the degree of polarization at single vesicles were made by flow cytometry using diphenylhexatriene as the optical probe. Vesicles differing in phase transition temperature could be distinguished by their degree of polarization at a temperature where one population was in the fluid (T greater than Tt) and the other one in the quasi-crystalline (T less than Tt) state. Besides vesicles containing exchange lipids we also observed fractions of unaffected vesicles. The lipid exchange was visualized directly by freeze-fracture electron microscopy. The characteristic 'ripple' structure of phosphatidylcholine vesicles disappeared upon exchange with lipid in the fluid state.

Carrier Proteins↗
PubMed1982

Adenylate Levels, Energy Charge, and Phosphorylation Potential during Dark-Light and Light-Dark Transition in Chloroplasts, Mitochondria, and Cytosol of Mesophyll Protoplasts from Avena sativa L.

The compartmentation of cellular energy relations during dark-light and light-dark transitions was studied by means of a newly developed technique to fractionate oat (Avena sativa L., var. Arnold) mesophyll protoplasts. Using an improved microgradient system with hydrophobic and hydrophilic layers of increasing density, a pure plastid pellet (up to 90% of total chloroplasts) could be separated from an interphase of only slightly contaminated mitochondria (70 to 80% of total mitochondria), and a cytoplasmic supernatant could be obtained within 60 seconds. Appropriate controls indicate that, under the conditions employed, metabolic interconversions of adenylates can be kept to a minimum and, thus, be determined and corrected for. Cross contamination of the fractions, as well as liberation of organelles to the supernatant, was assessed by specific markers, and the metabolite levels recorded were corrected accordingly. Using this technique, we found that, during dark-light transition, the chloroplastic and cytosolic ATP exhibits a rapid increase, while the mitochondrial ATP level decreases. In all compartments, ADP levels mirror alterations of the ATP pool in the opposite way, at least to some extent. To compensate fully for the rise in ATP, chloroplastic and mitochondrial AMP levels change accordingly, indicating that, due to the more or less unchanged level of total adenylates, there is no net flux of adenylates between the compartments. In contrast to the organelles, no AMP could be detected within the cytosol. When the light is turned off, a decrease of ATP coincides between chloroplast stroma and the cytosol for only about 30 seconds. Under prolonged dark treatment, cytosolic ATP rises again, while stroma ATP levels exhibit a further decrease. After about 60 seconds of darkness, the cytosolic ATP level is back to its initial value. This obviously is due to the immediate rise in mitochondrial ATP upon darkening, which cumulates after about 60 seconds; then, caused by an ATP/ADP exchange with the cytosol, it levels off again at the state before changing the conditions, as soon as the cytosolic ATP is also back to its original level. All of these events are closely mirrored by the change in the ATP/ADP ratio and the energy charge within the compartments. While the values for chloroplasts exhibit considerable differences between dark and light, those calculated for mitochondria and the cytosol exhibit only transient changes. These are limited to about 60 seconds of undershoot or overshoot, with respect to the cytosol, and then return to nearly the levels observed before changing the conditions. Adenylate kinase was found to be exclusively associated with chloroplasts (90% of total activity level) and mitochondria. Isotonic liberation of vacuoles did not point toward a significant association of adenylates with this compartment.The results are discussed with respect to an effective collaboration between photosynthetic and oxidative phosphorylation in order to keep the cytosolic energy state at a constant, preset value.

Journal Article↗
PubMed1982

Mass spectrometric 13C/12C determinations to detect high fructose corn syrup in orange juice: collaborative study.

The 13C/12C ratios in orange juice are sufficiently uniform and different from those in high fructose corn syrup (HFCS) so that the addition of HFCS to orange juice can be detected. HFCS averages -9.7% (parts per thousand) delta 13C, orange juice averages -24.5%, and mixtures of HFCS and orange juice possess intermediate values. One pure orange juice and 4 orange juice -HFCS mixtures containing from 25 to 70% orange juice were properly classified by 7 collaborators. Samples with delta 13C values less negative than -22.1%, 4 standard deviations from the mean of pure juices, can, with a high degree of confidence, be classified as adulterated. Samples with values more negative than -22.1% must be considered unadulterated with HFCS, because pure orange juices possess a range of delta 13C values. The 13C/12C mass spectrometric method was adopted official first action for detecting HFCS in orange juice.

Beverages↗