PubMed Health⌕ Search

Biomedical subjects

J Müller

Publications and source records attributed to J Müller.

At least 469 records · Page 26Linked to original sources
PubMed1992

Function of an Ultrabithorax minigene in imaginal cells.

An Ultrabithorax (Ubx) minigene constructed from three key Ubx control regions is capable of supporting development of Ubx null mutants throughout larval life and beyond to pharate flies, thereby rescuing the larval lethality due to the homeotic mutation. The cuticle of these flies shows that the minigene provides at least partial Ubx function in each of the four compartments whose morphogenetic pathways are determined by Ubx. We analyse beta-galactosidase patterns in imaginal discs conferred by each individual Ubx control region. From the comparison of these patterns with Ubx expression in Cbx mutants, we infer that long-range repressor elements in the chromosomal Ubx gene play an important role in the generation of Ubx expression patterns in imaginal discs. Expression and function of our Ubx minigenes indicate that Ubx control regions are capable of functioning properly out of context and detached from their normal chromosomal location within the homeotic gene complex.

Animals↗
PubMed1992

[Echinococcosis of the temporal bone--epidemiology, diagnosis, therapy and review of the literature].

A case of primary echinococcosis or hydatid disease of the temporal bone is reported in which no other organ system was involved. Epidemiology, diagnostic problems, clinical findings and therapy in relationship to the available literature are reviewed. In the patient described, complete surgical removal of the parasitic cysts was required as well as chemotherapy with Mebendazole.

Adult↗
PubMed1992

[Lactate acidosis in the course of status asthmaticus--case report].

A case report of lactate acidosis in the course of status asthmaticus in a 34 year old female is presented. The lactate acidosis was due to increased anaerobic glycolysis in respiratory muscles caused by decreased oxygen recruitment and increased oxygen consumption by respiratory muscles. The authors discuss the clinical significance of lactate acidosis and proper treatment of status asthmaticus.

Acidosis, Lactic↗
PubMed1992

Effect of head-down tilt bedrest (10 days) on lymphocyte reactivity.

Immunological responses of six healthy males to 10 days of head-down tilt bedrest (HDT) were assessed. Lymphocyte responsiveness was severely reduced immediately before, during, and immediately after the HDT, even though the lymphocyte numbers did not change. By contrast, delayed-type hypersensitivity was not affected. No dramatic changes were found in WBC counts and lymphocyte subpopulations, with the only exception of natural killer (NK) cells which transiently decreased immediately after HDT. Plasma cortisol levels were elevated above normal immediately before and during the HDT. The data suggest that the mitogenic response of lymphocytes was affected by psychological and fluid shift stress. These results are compared with data obtained during and after spaceflight. We conclude that the stress of HDT induces changes in immunological responsiveness that are strikingly similar to those arising from the stress of spaceflight.

Adult↗
PubMed1992

[The bioequivalence of two different batches of two nifedipine controlled-release preparations with deficient batch conformity in in vitro liberation studies].

The pharmacokinetics of two batches of two different nifedipine (CAS 21829-25-4) controlled release formulations (product 1 or 2, respectively) were investigated during two randomized double-blind cross-over studies testing two treatments each in two separate treatment periods with a total of 40 (2 x 20) healthy male volunteers. Plasma concentrations of nifedipine were determined up to 48 h after administration of 20 mg nifedipine. In spite of different in vitro release rates a positive bioequivalence was determined for product 1, while no bioequivalence could be proven with the investigated batches of product 2. This is compatible with the different in vivo release rates. Therefore, a different in vitro release of a drug does not necessarily lead to a negative bioequivalence decision. On the other hand, deficient conformity of batches in vitro can go along with missing bioequivalence in vivo. A harmless substitution of formulations containing equal substances requires their therapeutical equivalence. A constantly high pharmaceutical quality is required to avoid therapeutic risks.

Delayed-Action Preparations↗
PubMed1992

[Suprapubic urinary diversion using Cystofix--an alternative to the urethral indwelling catheter].

Suprapubic Cystofix-cystostomy is a valuable alternative to the Foley-catheter. The advantages of suprapubic cystostomy are mainly a reduction of urinary tract infections, inflammatory reactions in the lower urinary tract and avoidance of late urethral strictures after transurethral catheterism. There are a few contraindications to be considered, mainly an empty bladder and coagulation disorders. The complication rate of suprapubic Cystofix-cystostomy, usually gross haematuria, is very low. Cystofix-cystostomy is as useful for short term urinary drainage as for long term drainage in the case of chronic voiding disorders.

Catheters, Indwelling↗
PubMed1991

Peroxisomal degradation of leukotrienes by beta-oxidation from the omega-end.

Chain shortening via beta-oxidation from the omega-end has been recognized as the major pathway for the degradation of cysteinyl leukotrienes as well as leukotriene B4 (LTB4). The metabolic compartmentation of this pathway was studied using peroxisomes purified from normal and clofibrate-treated rat liver. beta-Oxidation products of omega-carboxy-LTB4, including omega-carboxy-dinor-LTB4 identified by gas chromatography-mass spectrometry, were formed by the isolated peroxisomes. The reaction was dependent on CoA, ATP, and NAD and was stimulated by FAD. NADPH was necessary for the further metabolism of omega-carboxy-dinor-LTB4. Together with microsomes a degradation of omega-carboxy-LTB4 also proceeded in isolated mitochondria in the presence of CoA, ATP, and carnitine. beta-Oxidation of the cysteinyl leukotriene omega-carboxy-N-acetyl-leukotriene E4 was observed only with isolated peroxisomes in combination with lipid-depleted microsomes. Direct photoaffinity labeling using omega-carboxy-[3H] LTB4 and omega-carboxy-N-[3H]acetyl-LTE4 served to identify peroxisomal leukotriene-binding proteins. The bifunctional protein (EC 4.2.1.17 and 1.1.1.35) and 3-ketoacyl-CoA thiolase (EC 2.3.1.16) of the peroxisomal beta-oxidation system were the predominantly labeled polypeptides as revealed by precipitation with monospecific antibodies. In vivo studies with N-acetyl-[3H2]LTE4, N-acetyl-[3H8]LTE4, and N-[14C]acetyl-LTE4 after treatment with the peroxisome proliferator clofibrate indicated formation and biliary excretion of large amounts of metabolites more polar than omega-carboxy-tetranor-N-acetyl-LTE3 including omega-carboxy-tetranor-delta 13-N-acetyl-LTE4 and omega-carboxy-hexanor-N-acetyl-LTE3. Increased formation of beta-oxidized catabolites of N-acetyl-LTE4 and LTB4 was also observed in hepatocytes isolated after clofibrate treatment. Our results indicate that peroxisomes play a major role in the beta-oxidation of leukotrienes from the omega-end. Whereas omega-carboxy-LTB4 was beta-oxidized both in isolated peroxisomes and mitochondria, the cysteinyl leukotriene omega-carboxy-N-acetyl-LTE4 was exclusively degraded in peroxisomes.

Affinity Labels↗
PubMed1991

A constitutive, heat shock-activated neutral trehalase occurs in Schizosaccharomyces pombe in addition to the sporulation-specific acid trehalase.

Trehalase was studied in Schizosaccharomyces pombe cells growing vegetatively on minimal medium and in sporulating cultures. Acid trehalase activity, measured at pH 4.2, was absent in vegetative cells and occurred only in asci, indicating that this activity represented the sporulation-specific trehalase reported previously. In contrast, neutral trehalase, measured at pH 6.0, was constitutively present in vegetative cells during the exponential and stationary growth phase as well as in asci. In vegetative cells, neutral trehalase did not sediment with cell walls, suggesting a cytoplasmic localization. Its activity increased ten-fold when growing cells were subjected to heat treatment of 2 h. Neutral trehalase from heat-treated cells had a pH optimum of 6.0 and was almost completely inhibited by 3 mM ZnCl2. Acid trehalase activity could be measured in intact asci, indicating that it is localized in the ascus cell walls, while neutral trehalase was not detectable in intact asci and appeared to be present primarily in the walls of ascospores and in the ascus epiplasm.

Cell Wall↗
PubMed1991

[Useful and pointless steroid determinations: appropriate laboratory diagnosis of adrenal cortex function].

A generation ago, the determination of urinary 17-hydroxycorticoids was the best available laboratory procedure for assessing adrenocortical function. Today, the plasma cortisol concentration, measured by radioimmunoassay, is a much more specific and reliable parameter, particularly in combination with simple functional tests, which are also suitable for ambulatory patients. The most appropriate tests of adrenocortical function for the diagnosis or exclusion of Cushing's syndrome or of primary and secondary adrenocortical failure are briefly described. Substitution therapy in patients with adrenocortical insufficiency must be evaluated by clinical criteria and not by steroid analysis.

17-Hydroxycorticosteroids↗
PubMed1991

Long range repression conferring boundaries of Ultrabithorax expression in the Drosophila embryo.

In an attempt to reconstruct the embryonic expression pattern of the homeotic gene Ultrabithorax (Ubx) by stable integration of fusion constructs, we identified three key control regions called PBX, ABX and BXD. Each of these confers an expression pattern mimicking certain aspects of Ubx expression. The PBX and ABX patterns are limited to the Ubx domain with anterior boundaries at parasegments 6 and 5. In contrast, the BXD pattern extends from head to tail. PBX or ABX expression boundaries are imposed on the BXD pattern, if PBX or ABX is linked to BXD. These boundaries, although not the PBX and ABX expression limits themselves, are dependent on Polycomb function. We conclude that PBX and ABX are recognized by repressors which act across large distances to suppress BXD activity. Stable and heritable Ubx expression boundaries are thus mediated by this process of long range repression.

Animals↗
PubMed1991

Bacterial endotoxins: comparison of mitogenic, polyclonal, antibody-inducing and toxicity activities.

The mitogenic effects on mouse spleen lymphocytes were determined in a large series of commercially available and laboratory-prepared lipopolysaccharides (LPS) obtained from Escherichia, Salmonella, Serratia and Shigella species; part of these LPS preparations was chemically modified prior to testing. In order to establish whether the degree of mitogenic activity corresponds with other biological effects of these preparations, polyclonal activity, capability to induce specific antibody formation and toxicity were determined for selected LPS's with different mitogenic effects. Some of the detoxication procedures used succeeded in reducing the toxicity of LPS while preserving its high mitogenic activitione of the Fe-detoxified preparations of LPS (from the R-form of Shigella dysenteriae serovar 1) exhibited a medium-degree efficacy in all parameters studied. Generally, there was no correlation between the degree of mitogenic activity and the polyclonal and antibody-inducing activities, but in some instances polyclonal activity did correlate with the antibody-inducing activity.

Animals↗
PubMed1991

An experimental study of vertical deviations induced by different interocclusal recording materials.

This study was designed to determine vertical deviations in mounting casts on an articulator as affected by the recording material. Five different recording materials were tested after storage of the records for 30 minutes, 6 hours, and 24 hours. Two measuring systems were used to register simultaneously the vertical errors at the occlusal plane and at the condyle of an articulator. The results indicated that the measurements made at the condyle cannot detect the vertical deviations induced at the occlusal surfaces. None of the materials tested gave reliable results. Advantages, disadvantages, and indications of the different materials were discussed.

Bicuspid↗
PubMed1991

Prevalence of carcinoma in situ and other histopathological abnormalities in testes from 399 men who died suddenly and unexpectedly.

To determine the prevalence of carcinoma in situ of the testis and other testicular histopathological abnormalities in the general male population, we examined gonads from 399 men 18 to 50 years old who died suddenly and unexpectedly. No sign of malignancy was found in any of these gonads. However, 3 of the 399 men had been previously treated for testicular tumor or carcinoma in situ. Thus, the over-all prevalence of testicular neoplasia in the population studied was 0.8% (95% confidence limits 0.2 to 2.2%). This frequency is of the same magnitude as the lifetime risk of testicular cancer in the Danish male population. The median weights of the left and right testes were 19.3 and 19.7 gm., respectively. This difference was statistically significant (p = 0.00003). Thus, our study confirmed that on average the left testis is smaller than the right testis. The median weight of the gonads collected in our study was 0.9 gm. lower than the weight of testes examined 40 years earlier at the same department of forensic medicine. However, this difference was not statistically significant (p = 0.17). Microscopic examination of the gonadal specimens revealed that 83% of the men exhibited complete spermatogenesis, including late spermatids in all tubules. In the age group studied we found no age-related changes in testicular weight or in the proportion of tubules with degenerative changes, such as spermatogenic arrest, the Sertoli-cell-only syndrome or hyalinization.

Adolescent↗