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J Müller

Publications and source records attributed to J Müller.

At least 721 records · Page 40Linked to original sources
PubMed1982

[Excretion of methylated nucleosides in the initial therapy phase in a case of anorexia nervosa].

The urinary excretion of six methylated ribonucleosides was measured in a case of anorexia nervosa during the first eight weeks of therapy. Four phases can be distinguished. Highly elevated values are found in a clearly catabolic situation. Immediately after onset of therapy when catabolism is stopped but nutrition still inadequate the excretion of RNA-catabolites is lowered markedly. As soon as normocaloric nutrition is reached after two weeks, a short but clearcut peak-excretion can be observed. Finally, the excretion of methylated RNA-catabolites is stabilized on an intermediate level after three to six weeks, when nutrition is constantly normocaloric and weight continues to increase linearly.

Adenosine↗
PubMed1982

[Origin of extraorthosympathetic nerve fibers innervating the epiphysis of the rat (study of retrograde transport of horseradish peroxidase)].

After horseradish peroxidase was injected into the rat pineal gland, isolated and rare labelled perikarya appeared in the central nervous system, particularly in the habenula, colliculi, amygdala, paraventricular and suprachiasmatic nuclei, preoptic area and olfactive centers. This indicates that the innervation of the pineal gland is not only orthosympathetic but that some stimuli can be directly transmitted from the brain to the pineal stalk.

Animals↗
PubMed1981

Stability of lactate dehydrogenase. II. Hybrids and geometric isomers.

Hybrids of lactate dehydrogenases from pig heart and muscle and from chicken heart and pig heart were obtained by the freeze-thaw method [1,2]. Ion-exchange chromatography of the resulting mixtures of hybrids yielded unusual elution patterns, i.e., the 2 + 2 hybrids (HP2MP2 and HC2HP2) were eluted in two separate peaks. These subforms were concluded to result from partial resolution of the three geometric isomers. The hybrids of chicken heart and pig heart lactate dehydrogenase showed three distinct levels of stability. The characteristics temperatures of denaturation were 61.5 degrees C for HP4, HCHP3 and HC2HP2I; 71 degrees C for HC2HP2II and HC3HP and 76.5 degrees for HC4. The resistance towards thermal denaturation thus seemed to be governed by the least stable dimer within the tetrameric enzyme. The arrangement of stabilities of the dimers was in excellent agreement with the number of additional ion pairs between Arg241 (chicken) and Asp57 (chicken and pig) [3] within the Q-contact areas. The rate-determining step of thermal denaturation of lactate dehydrogenase was concluded to comprise the distortion or dissociation of one or two Q-contacts of the tetramer.

Animals↗
PubMed1981

[Incidence and clinical manifestation of ACTH-producing pituitary adenoma after bilateral adrenalectomy for Cushing's syndrome (Nelson syndrome)].

29 out of 39 patients bilaterally adrenalectomized for pituitary-dependent Cushing's syndrome between 1958 and 1979 have been followed up at regular intervals. ACTH-producing pituitary adenomas were detected and removed in 9 of them up to 1981. In 4 additional patients an enlarged sella turcica was already found at the time they had Cushing's syndrome, and therefore they were first treated by pituitary surgery or radiotherapy. In the adrenalectomized patients hyperpigmentation was the major clinical symptoms of the adenoma. Only in three instances did extrasellar growth of the adenoma cause ophthalmoplegia or narrowing of the visual fields. The existence of intrasellar ACTH-producing microadenomas in 5 additional patients seems highly probable in view of hyperpigmentation, excessively elevated plasma ACTH concentrations and radiological evidence of sella deformations. These observations indicate that in patients adrenalectomized for pituitary-dependent Cushing's syndrome ACTH-producing adenomas are more common than previously assumed. Moreover, according to recent reports, ACTH-producing microadenomas are frequently found in pituitary-dependent Cushing's syndrome and are assumed by many clinical endocrinologists to be the primary cause of this disease. Therefore, bilateral adrenalectomy is no longer the undisputed therapy of first choice and it is necessary in each individual case to consider carefully whether an attempt to remove selectively an ACTH-producing pituitary adenoma by microsurgery might not be preferable.

ACTH Syndrome, Ectopic↗
PubMed1981

Stability of lactate dehydrogenases. I. Chemical modification of lysines.

The lysine residues of lactate dehydrogenase (L-lactate: NAD+ oxidoreductase, EC 1.1.1.27) can be amidinated by methyl-4-hydroxy-3-nitrobenzimidate to introduce nitrophenolate anions. This modification results in lowered thermal stability, as does acetylation. The conversion of these groups into uncharged aminophenol groups without further modification of the enzyme itself stabilizes the enzymes from pig heart and muscle and from chicken muscle, as does acetamidination, but the unusually stable enzyme from chicken heart reverts only to the stability of the native form. The results allow for the following conclusions. Destabilization is brought about at many points at the surface of lactate dehydrogenases by neutralization of positive charges. Stabilization, in contrast, is concluded to be due to modification of one lysine at position 241 of the sequence. This lysine must have been changed to arginine during the evolution of heart-type lactate dehydrogenases in going from lower to higher reptiles. This exchange has been conserved in the enzymes from the hearts of birds and therefore the enzyme from chicken heart is very stable and cannot further be stabilized by modification of lysines. From X-ray structure analysis, the stabilization by exchange of Arg for Lys at position 241 or by amidination is explained by the formation of additional ion pairs with aspartic acid57 of the Q-related subunits.

Animals↗
PubMed1981

[Secondary diseases complicating cancer].

Post-operative care of cancer patients has to take into consideration additional diseases not related to the basic disease, too. This is especially of importance in cases in which these diseases are decisive for the patient's expectation of life. In view of the age structure of cancer patients, a high incidence of diseases of circulation and their risk factors is to be expected. In the present study 480 cancer patients were examined retrospectively for their multimorbidity. It confirmed the high incidence of risk factors (27% hypertension, 17% diabetes mellitus) and of diseases of circulation (60% cardiac failure, 20% coronary heart disease, 15% peripheral disturbances of arterial circulation). These complicating diseases were overlooked in many cases in view of the "tragedy of cancer".

Cardiovascular Diseases↗
PubMed1981

[Metabolic evaluation and etiology of "preclinical hypothyroidism": a preliminary report].

The TRH test, using synthetic TRH (TSH-releasing hormone) is the most sensitive test for the assessment of thyroid function. It may show elevated basal TSH and/or an exaggerated TSH response to TRH, despite normal thyroid hormone levels (T4, FT4I, T3). This condition is termed "preclinical hypothyroidism" (pc hypo). Thyroid hormone levels, the clinical index of Billewicz and metabolic impact on target tissues were studied prospectively in 38 pc hypo women and compared with 20 controls matched for age, weight and sex and 9 patients with overt hypothyroidism. For metabolic evaluation at the tissue site two new metabolic tests were developed and standardized, the systolic time intervals (STI) and sex-hormone-binding globulin (SHBG), which were used in conjunction with the ankle reflex time (ART) and lipids (cholesterol and triglycerides). The thyroid hormones T4, FT4I and T3 in pc hypo (77.8 +/- 2.0 nmol/l; 71.8 +/- 2.3; 1.92 +/- 0.07 nmol/l respectively; mean +/- SEM) were within the normal range (by definition), but significantly lower in comparison with the normal controls (105.5 +/- 3.3 nmol/l; 97.8 +/- 3.1; 2.91 +/- 0.12 nmol/l respectively; p less than 0.001). The clinical index and metabolic parameters SHBG and ART showed significant hypothyroid changes. STI (measured as preejection period) and lipids were not yet significantly different from the controls despite a hypothyroid tendency in many single individuals. The etiology in 144 patients with pc hypo (out of 2969 TRH tests) was analysed and the following causes identified: a) treated hyperthyroidism (38 after radioiodine, 5 after partial thyroidectomy, 5 after antithyroid drugs, 5 after radioiodine and partial thyroidectomy); b) simple goiter (7 without and 21 after partial thyroidectomy); c) autoimmune thyroiditis (27); d) other causes such as subacute thyroiditis (10); Riedel's thyroiditis (2), dyshormogenesis (2), drugs (6), treated toxic adenomas (2); e) etiology unknown or not identified (14).

Aged↗
PubMed1981

Nitroblue-tetrazolium test for the functional evaluation of phagocytic cells: a critical analysis of the methodology.

The reduction of NBT to formazan has been suggested as an indicator of the reduction potential of biological systems. An increase in the amount of reduced formazan reflects the activation of the hexose monophosphate shunt of phagocytes cultivated in vitro, as a result of cellular stimulation by chemical or biological factors, or during phagocytosis. This phenomenon has been widely used for the determination of activated phagocytes by different methods. However, the technical limitations of these methods have not been evaluated carefully. In the investigations presented here three solvents for formazan, pyridine, dioxane and dimethyl-formamide, have been tested for their suitability as extraction agents. For each solvent the optimal wavelength for photometric evaluation has been determined and dose relation curves between dissolved formazan and OD have been established. Several factors (time, temperature, pH, contamination with water or acid) affecting the dissolving properties and stability of formazan in different solvents have been investigated. With the solvents tested, dioxane proved to be the most suitable agent for extracting NBF. Thus a methodology for the quantitative evaluation of NBT has been established. This method can be used for the identification of activators as well as of inhibitors of the phagocyte system.

Chemical Phenomena↗
PubMed1981

[Presentation of the cooperative study COALL-80 on treatment of childhood ALL (author's transl)].

The cooperative study COALL-80 is derived from the BFM-78-study. The aim of the study is a reduction of the initial therapy-morbidity and -mortality without loss of efficacy by omitting asparaginase from the four drug-induction regimen and interposing it between induction- and CNS-therapy phase. The expected two years disease free survival rate of a pilot study will be 82%. This finding is hitherto comparable with the BFM-study results.

Adolescent↗
PubMed1981

Aneuploidy as a marker for carcinoma-in-situ of the testis.

A microspectrophotometric study of the DNA content of carcinoma-in-situ germ cells in the testes of eight infertile men revealed an aneuploid DNA distribution pattern. The results support the assumption that carcinoma-in-situ germ cells are of a malignant nature. The findings also indicate that the DNA content can be used to discriminate between carcinoma-in-situ germ cells and spermatogonia.

Aneuploidy↗
PubMed1981

Stimulation of aldosterone biosynthesis by experimental edema: role of the kidneys.

The role of the kidneys in the stimulation of aldosterone biosynthesis by sodium sequestration was investigated in potassium-depleted rats. After 2 wk on a potassium-deficient diet, rats were treated by subcutaneous injections of polyethylene glycol or formalin and were then kept on sucrose and water for 24 h. Either type of experimental edema markedly enhanced the conversions of tritiated deoxycorticosterone and corticosterone to aldosterone and 18-hydroxycorticosterone by incubated capsular portions of the adrenal glands and partially normalized the deranged pattern of endogenous corticosteroid output in response to serotonin. Bilateral nephrectomy completely blocked these effects of edema on the zona glomerulosa. When uremia was induced by bladder resection, with the kidneys left intact, edema still significantly stimulated aldosterone biosynthesis. Irrespective of increases in the plasma creatinine, the plasma potassium remained at uniformly low levels in all experimental groups of animals. According to these observations, experimental edema stimulates late steps of aldosterone biosynthesis in potassium-depleted rats by mediation of the kidneys, most likely through the renin-angiotensin system.

18-Hydroxycorticosterone↗
PubMed1981

Nonspecific esterase in human lymphocytes.

A substantial proportion of human peripheral lymphocytes exhibits esterase activity as demonstrated by cytochemical techniques using hexazotized pararosanilin as coupling agent and different alpha-naphthyl compounds, in particular alpha-naphthyl-acetate, as substrates. Esterase-positive lymphocytes showed one or several dots of the reaction product. Plasma cells and macrophages also exhibited marked esterase activity but with diffuse distribution of the reaction product throughout the cytoplasm. The substrate specificity, the time course and the pH optimum of the cytochemical reaction were determined. The results indicate that these lymphocyte esterases are identical with acid lipases. The number of esterase-positive cells reaches a plateau well below 100% (85% for blood lymphocytes) even with optimal staining procedures. The relation between esterase activity and other so-called lymphocyte markers such as sIg and the capacity to form spontaneous rosettes with sheep red blood cells was investigated in peripheral human blood lymphocytes. A fair correlation between rosette formation and esterase activity was found and most of the esterase-positive cells were sIg-negative. However, the fit was never complete. The results suggest that esterase activity is largely characteristic for small peripheral T cells. Almost all blast cells formed following stimulation with Con A or PHA were esterase-positive. Histochemical studies showed that the large majority of the thymocytes in the cortex lacked esterase activity. In lymph nodes, a low proportion of esterase-positive cells was found in the germinal centers, whereas most lymphocytes in the paracortical are were esterase-positive.

Adolescent↗