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Biomedical subjects

A Zimmermann

Publications and source records attributed to A Zimmermann.

At least 325 records · Page 18Linked to original sources
PubMed1986

Feminization in a galactosemic girl in the presence of hypergonadotropic hypogonadism.

A galactosemic girl has been followed in our clinic since her 8th day of life when the diagnosis of transferase-deficiency galactosemia was made until her present age of 21 years. Although she presented with direct hyperbilirubinemia and severe liver dysfunction, her subsequent somatic and intellectual development under a strict galactose-free diet was normal. Liver function normalized. Her pubertal stage was Tanner B II and PH II at age 11.7 years and progressed normally to B V and PH V, but menarche did not occur. At age 16.8 years, low estradiol (51 pmol/L) and high gonadotropin levels (LH 44 U/L; FSH 43 U/L) were measured. Severely hypoplastic ovaries with a streak-like aspect were seen on laparoscopy. Sex chromatin was positive. Follow-up studies over the next 4 years confirmed elevated LH and FSH levels with an excessive response to stimulation with LHRH and persistently low estradiol levels (41 to 117 pmol/L). After an intravenous load of 200 mg DHEA-S, plasma estrone levels rose 1.8-fold and estradiol 11.4-fold above basal, demonstrating prompt conversion of androgens to estrogens. For over one year, the patient has been treated with the synthetic progestin norethisterone (15 mg per day for 10 days in a row every month) which has resulted in regular menstrual bleedings.

Adult↗
PubMed1986

Shape changes and chemokinesis of Walker 256 carcinosarcoma cells in response to colchicine, vinblastine, nocodazole and taxol.

Two morphologically distinct types of polarization and locomotion are found in Walker carcinosarcoma cells. Spontaneously polarized cells are characterized by formation of ruffles and spikes, cells polarized in the presence of microtubule-disassembling drugs by blebbing at the leading edge. Polarization and locomotion are closely correlated. Both can be stimulated by the microtubule-disassembling agents colchicine, nocodazole and vinblastine and suppressed by taxol or cytochalasin B. The results suggest that both microfilaments and microtubules may be involved in regulating polarization and chemokinesis, and that shape changes elicited by microtubule-disassembling agents depend on microfilaments.

Alkaloids↗
PubMed1986

Severe liver fibrosis in argininosuccinic aciduria.

Hepatomegaly is an important clinical finding in patients with argininosuccinic aciduria (a hereditary defect of the urea cycle enzyme, argininosuccinate lyase [argininosuccinase]). A severe degree of liver fibrosis, almost corresponding to cirrhosis, was observed in liver biopsy material obtained from a boy with this disorder. This observation is of interest in light of the fact that liver fibrosis or cirrhosis are hallmarks of many inheritable phenotypes, and especially of inborn errors of metabolism. Variable degrees of liver fibrosis are noted in other inborn defects of the urea cycle, eg, in ornithine transcarbamylase and carbamoylphosphate synthetase deficiencies. These findings appear to indicate that inheritable defects of urea synthesis may form a group of metabolic disorders prone to cause hepatic fibrosis, or even cirrhosis, as shown in our patient.

Amino Acid Metabolism, Inborn Errors↗
PubMed1985

Phorbol myristate acetate (PMA) suppresses polarization and locomotion and alters F-actin content of Walker carcinosarcoma cells.

This study demonstrates a novel feature of PMA, its ability to suppress chemokinetic polarization and locomotion of tumor cells. Walker carcinosarcoma cells exhibit two distinct types of polarization and locomotion, i.e. spontaneous polarization characterized by ruffles at the front and stimulated polarization and locomotion in response to the microtubule-disassembling agents colchicine, vinblastine and nocodazole, which are characterized by blebbing at the front. The tumor promotor phorbol myristate acetate (PMA), but not phorbol, was found to suppress both types of polarization and random locomotion at concentrations between 10(-8) and 10(-6)M. The effect of 10(-6)M PMA was virtually complete within 5 min. Inhibition of locomotion was due to both a reduction in the speed of migrating cells and the proportion of migrating cells. Changes in shape and chemokinesis of Walker carcinosarcoma cells were associated with alterations in the relative amount and the topographical distribution of F-actin as determined by NBD-phallacidin binding. Suppression by PMA was associated with loss of the polar topographical distribution of F-actin visualized by NBD-phallacidin binding. In the presence of PMA, the relative amount of F-actin was higher than in unstimulated controls and lower in cells exposed to microtubule-disassembling agents.

Actin Cytoskeleton↗
PubMed1985

Calcium transport by red blood cell membranes from young and adult cattle.

It is shown using inside-out membrane vesicles that cattle red cells extrude calcium by means of a calmodulin sensitive Ca-pump whose activity is high in calves and extremely low in adult cows. The decline is not due to loss of calmodulin susceptibility nor to a drop in Ca-affinity.

Adenosine Triphosphate↗
PubMed1985

Orthokinetic and klinokinetic responses of human polymorphonuclear leucocytes.

Evidence is presented to show that klinokinesis, which was previously demonstrated in bacteria and amoeba only, may also occur in metazoan cells. The chemotactic peptide formyl-Met-Leu-Phe (fMLP) elicited orthokinetic and klinokinetic responses of human blood-borne polymorphonuclear leucocytes (PMNs) under the test conditions used. Increased speed (orthokinesis) was due to an increase in the proportion of migrating cells as well as in the speed of the locomoting subset. The klinokinetic effect was manifested by a decrease in the klinolocomotion index, the mean angle of changes in direction greater than or equal to 90 degrees, and the frequency of turns greater than or equal to 90 degrees. The klinolocomotion index was inversely related to speed. This explains the synergistic effect of klinokinesis and orthokinesis in this system. Colchicine alone had an orthokinetic effect which was exclusively due to alterations in the proportion of migrating cells and it altered the turning behaviour without exerting a klinokinetic effect. However, colchicine had marginal orthokinetic and klinokinetic effects on fMLP-stimulated cells resulting in reduced translocation. The relationship between klinokinesis and mean angle or frequency of turns has been analysed. Klinokinesis was a substantial though not the major element of the chemokinetic response to fMLP under the conditions used. No other metazoan cells have been shown to possess such a complete pattern of responses, including orthokinesis, klinokinesis, and chemotaxis, which regulate locomotion.

Bacterial Physiological Phenomena↗
PubMed1985

The spatial and temporal pattern of beta NGF receptor expression in the developing chick embryo.

To gain insight into the developmental program of nerve growth factor (NGF) receptor expression, the binding of [125I] beta NGF to frozen chick sections was investigated autorradiographically between embryonic day 3 (E3) and post-hatching day 3. Strong NGF receptor expression was observed as early as E4, throughout embryonic development and in the post-hatching period at the classical NGF target sites: the paravertebral sensory and sympathetic ganglia, the paraaortal sympathetic ganglia as well as the cranial sensory ganglia with neurons of neural crest origin and their respective nerves. Only weak [125I] beta NGF binding was observed during a restricted time span in the parasympathetic ciliary ganglion. Clear differences were observed in the intensity and in the developmental time course of [125I] beta NGF binding to the dorsomedial and ventrolateral aspects of the dorsal root ganglia. NGF receptors were also found to be expressed on central axons of the dorsal root entry zone and the dorsal tract in the spinal cord. A transient expression of specific NGF binding sites of the same high affinity as measured at the classical NGF targets, was detected in the lateral motor column and in muscle at the time of motoneuron synapse formation and elimination.

Age Factors↗
PubMed1985

Liver pathology in a new congenital disorder of urea synthesis: N-acetylglutamate synthetase deficiency.

Detoxification through the urea cycle is the means by which mammalian organisms dispose of their excess ammonia. Within this cycle, N-acetylglutamate (NAG) is the most important cofactor for optimal enzyme activity. It is formed from acetyl CoA and glutamate through the action of N-acetylglutamate synthetase (NAGS). Recently, a congenital deficiency of NAGS has been reported. In this communication, we present results of structural investigations on liver tissue of the index patient with NAGS defect. Light microscopy revealed small, eosinophilic inclusions in some of the hepatocytes. Electron microscopy showed vesicular SER and fibrillar material in expanded cisterns of the RER, presumably corresponding to the inclusions seen in light microscopy. Immunofluorescence of liver tissue uncovered a discrete distribution of intracellular albumin in the form of small deposits. We suggest that in NAGS deficiency, some secretory proteins might be incompletely processed due to the lack of a protease activator, NAG.

Acetyltransferases↗
PubMed1985

The Piotron: II. Methods and initial results of dynamic pion therapy in phase II studies.

Negative pi-meson (pion) therapy employing dynamic scanning with a focused spot of convergent beams has been in use since 1981 at SIN. Three-dimensional conformation of the treatment volume to the target volume can thus be achieved. Following previously reported Phase I and Ib clinical trials, a Phase II trial was initiated with the goal of treating primary deep-seated tumors in a dose optimization schedule which included stepwise increase of total pion dose and of target volume. Patients with multicentric superficial bladder tumors who were cystectomy candidates were initially selected. Since then, more invasive cases have been treated. A graded scoring of acute tissue reactions was employed. Follow-up periods were from 10 to 20 months. The pion dose escalation ranged from 3000 rad (minimum) to 3600 rad (minimum) in 20 fractions over 5 weeks. The treatment volumes encompassed 190 cc for local to 1,820 cc for extended volume therapy. Treatment reactions ranged from a faint erythema and increase of bladder frequency to dry desquamation, mild nausea, moderate dysuria, and moderate proctitis or diarrhea with mucus. These reactions were closely related to treatment volume and site. One severe late cystitis has occurred in a patient treated with 2 courses of pions (4475 rad). Mild to moderate late proctitis has been seen in 4 patients. Ten of 13 bladder cancer patients had local control of disease while all 3 pancreas or biliary tract cancer patients had microscopic residual disease locally at time of death from metastasis. A total of 11 of 17 patients are thus clinically or pathologically free of local tumor to time of last observation.

Bile Duct Neoplasms↗
PubMed1985

Surgical repair of the kidney after blunt lesions of intermediate degree using a Vicryl mesh: an experimental study.

Twelve experimentally induced blunt renal lesions in pigs were treated either with an alloplastic renal capsule made of semi-elastic Vicryl mesh or with homologous pig fibrin adhesive or with through-and-through chromic catgut sutures as controls. The Vicryl mesh capsule was made by the Ethnor Company (Paris, France) to our specifications. The postoperative isotope nephrograms, which were repeated until the Vicryl had been fully resorbed, showed good renal function in every case. However, when compared to the controls, the kidneys which had been repaired with Vicryl mesh contained considerably less scar tissue at the site of parenchymal rupture and showed neither perirenal fibrosis nor atrophy of the parenchyma in the vicinity of the capsule. Our preliminary results seem to confirm that simple and rapid surgical treatment of moderately severe blunt renal lesions is possible using the alloplastic Vicryl mesh capsule. The method may also be suitable for reconstruction of the parenchyma following multiple nephrotomies, such as for removal of staghorn calculus, and experimental investigations are under way to clarify this point.

Animals↗
PubMed1985

Amiodarone-induced vasculitis and polyserositis.

A dose-dependent cutaneous leukocytoclastic vasculitis developed in a 34 year old man who was given amiodarone for supraventricular tachycardias resistant to other drugs. This adverse reaction disappeared within 2 weeks after discontinuation of amiodarone despite its very long half-life of 52 days in this patient. During previous treatment periods with amiodarone, the patient had experienced photosensitivity and dose-dependent polyserositis. Since high doses of amiodarone have been recently proposed for the treatment of resistant cardiac arrhythmias, dose-dependent adverse effects as described here may be encountered with increasing frequency.

Adult↗
PubMed1985

[Genetic heterogeneity and pathology of congenital nephrotic syndrome and its significance in prenatal diagnosis].

Familial occurrence of congenital nephrotic syndrome (CN) has been most extensively studied in Finland where it is known to be inherited as an autosomal recessive disease. In this Finnish type of congenital nephrotic syndrome (CNF) prenatal diagnosis by alphafetoprotein (AFP) determination in the amniotic fluid has been reported to be conclusive. Within the last six years we observed 10 cases of CN occurring in 5 families. In all patients renal histology has been studied. Although each family presented a different type of CN, the appearance within the same sibship was always identical.

Adult↗
PubMed1985

Results of curative pion therapy at SIN.

The experiences of the treatment of bladder carcinoma indicated the direction in which the dose optimization program of intraabdominal tumours can be carried out. Small intraabdominal target volumes seem to tolerate doses from 31 to 33 Gy applied in 20 fractions. The best results with local tumour control and low complication rates have so far been reached in carcinoma of the cervix. It has not so far been organizationally possible at SIN to treat with pions on more than four days per week. This restricts changes to the fractionation scheme in the treatment of highly malignant gliomas. An improvement of results could be possible on the basis of experience to date. The significance of a postbiopsy preoperative radiotherapy, of the increase of target volume and the increase of the total dose will be tested in a study by the SAKK (Swiss Group for Clinical Cancer Research).

Elementary Particles↗
PubMed1984

[Adult respiratory distress syndrome in extensive intra-alveolar metastasis of an amelanotic malignant melanoma].

The case is reported of a 26-year-old patient hospitalized after 6 days of coughing and dyspnea with the clinical picture of "adult respiratory distress syndrome" (ARDS). In spite of intensive therapeutic efforts, death ensued within a few weeks. Autopsy revealed widespread intraalveolar metastases of a hitherto unrecognized amelanotic malignant melanoma of the back. Further metastases were only detected in intrathoracic lymph nodes and in the myocardium. A possible relationship between this unusual pattern of metastasis and previous abuse of nicotine, alcohol and hashish, as well as coexisting hypogammaglobulinemia, is discussed. It appears that widespread intrapulmonary metastasis must be considered one of the possible causes of ARDS.

Adult↗
PubMed1984

Nemaline myopathy appearing in adults as cardiomyopathy. A clinicopathologic study.

We examined a 29-year-old woman with nemaline myopathy that appeared as cardiomyopathy. Clinical examination showed dilated cardiomyopathy, but no neuromuscular abnormalities of the skeletal muscles. Electromyography showed neither neurogenic nor myopathic abnormalities. A biopsy specimen from the quadripecs muscle showed typical nemaline bodies in about 50% of the muscle fibers. The patient died six months later of biventricular heart insufficiency. Autopsy revealed nemaline bodies in the working and conducting tissues of the myocardium. Earlier, the patient's mother and one of her sisters died unexplained, sudden deaths at the ages of 47 and 37 years, respectively. Sections of the myocardium taken from the sister at autopsy were available, and also disclosed nemaline bodies after restaining with trichrome.

Adult↗
PubMed1984

Effects of colchicine, vinblastine and nocodazole on polarity, motility, chemotaxis and cAMP levels of human polymorphonuclear leukocytes.

We present evidence for intrinsic polymorphonuclear leukocyte (PMN) polarity manifested in presence of microtubule-disrupting drugs. Polarization in response to colchicine correlated with the known dose-dependent effects of this drug on microtubule disassembly. The response to 10(-5) M colchicine, 10(-5) M vinblastine and 10(-6) M nocodazole was associated with stimulated motility and random locomotion. Responses elicited by microtubule-disrupting drugs differed from f-Met-Leu-Phe (fMLP)-induced polarization by functional and morphological criteria. Polarization, motility and orthokinesis responses were much weaker. Furthermore, ruffling was almost absent in PMNs polarized in response to colchicine, vinblastine or nocodazole. The response was inhibited by cytochalasin B, indicating that it is microfilament-dependent. We suggest that microtubule-disrupting drugs induce motility via structural changes in the cytoskeleton which act as signals for the motor apparatus. The intrinsic polarity manifested in the presence of microtubule-disrupting drugs could be reversed by an extracellular chemotactic gradient. Stimulated locomotion and motility in response to microtubule-disrupting drugs was only observed with initially spherical PMNs but not with initially motile cells. The findings provide an explanation for the numerous conflicting statements on the chemokinetic activities of these drugs. The role of cAMP in stimulated polarization and motility has been studied. Colchicine, vinblastine and nocodazole elicited a transient elevation of cAMP levels within 1 min of stimulation. cAMP elevation and stimulated motility were not quantitatively correlated.

Antineoplastic Agents↗