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T Moser

Publications and source records attributed to T Moser.

At least 37 records · Page 2Linked to original sources
PubMed1998

Low-conductance intercellular coupling between mouse chromaffin cells in situ.

1. Patch-clamp experiments were used to compare membrane properties of mouse chromaffin cells in thin tissue slices and of isolated cells in primary culture. The mean membrane input resistance (R(in)) and membrane capacitance were 3.1 +/- 0.6 G omega and 9.1 +/- 0.5 pF in situ and 9.9 +/- 1.8 G omega and 8.2 +/- pH in isolated cells. 2. Spike-like currents were observed on top of the calcium currents during depolarizations in thirty out of forty-nine cells in situ. They were not seen in isolated cells nor after addition of Cd2+ (100 microM) and TTX (10 microM) to the perfusate of the slices. The mean R(in) of cells which displayed current spikes (2.3 +/- 0.18 G omega) was significantly smaller than that of cells lacking spikes (3.9 +/- 0.25 G omega). It is suggested that the current spikes represent intercellular currents which result from action potential firing in neighbouring cells during the depolarization of the patch-clamped cell. 3. Investigation of capacitative currents induced by square voltage pulses showed a slow component in twenty-four out of twenty-seven cells in situ. 4. It is concluded that a large fraction of mouse chromaffin cells in situ are electrically coupled. From the slow capacitative currents and the amplitude of the intercellular current spikes a junctional conductance between chromaffin cells of below 1 nS was deduced. 5. This junctional conductance appears to be too low to support spreading of electrical activity in cases where a single cell is stimulated by an action potential. However, the junctional conductance could allow longer depolarizations of one cell or simultaneous firing of several cells to trigger electrical activity in neighbouring cells.

Animals↗
PubMed1998

Cytosolic Ca2+ acts by two separate pathways to modulate the supply of release-competent vesicles in chromaffin cells.

Recovery from depletion of the readily releasable pool of vesicles (RRP) in adrenal chromaffin cells was studied at differing basal [Ca2+]i or following protein kinase C (PKC) activation by phorbol esters. Following depletion, the pool size was estimated at varied times from cell capacitance jumps in response to paired depolarizations. The experimentally observed RRP recovery time course and steady-state size could be predicted from the measured [Ca2+]i signal assuming a Michaelis-Menten-type regulation of the vesicle supply by Ca2+. An elevated recruitment activity was observed at increased [Ca2+]i even when protein kinase C was blocked, but maximum effects could be obtained only after stimulation of PKC by phorbol esters or by prolonged elevations in [Ca2+]i. We suggest that, in chromaffin cells, elevated cytosolic Ca2+ modulates exocytotic plasticity via PKC-dependent and -independent pathways.

Animals↗
PubMed1998

Isolated hepatic perfusion with tumor necrosis factor and melphalan for unresectable cancers confined to the liver.

PURPOSE: To evaluate the efficacy and systemic and regional toxicities of hyperthermic isolated hepatic perfusion (IHP) using tumor necrosis factor (TNF) and melphalan for the treatment of unresectable primary or metastatic cancers confined to the liver. PATIENTS AND METHODS: Thirty-four patients (18 men and 16 women; mean age, 49 years) underwent a 60-minute hyperthermic (39.5 degrees to 40.0 degrees C) IHP performed by laparotomy that used TNF 1.0 mg and melphalan 1.5 mg/kg. Perfusion inflow was through the gastroduodenal artery and outflow was from a cannula positioned in an isolated segment of retrohepatic inferior vena cava (IVC). Infrahepatic IVC and portal venous blood flow were shunted to the axillary vein using an external venoveno bypass circuit. Complete vascular isolation of the liver was confirmed by an I-131-labelled human serum albumin monitoring technique. RESULTS: There was no operative mortality. Seventy-five percent of patients had reversible grade III or IV (National Cancer Institute Common Toxicity Criteria) hepatic toxicity with one treatment-related mortality (3%) because of hepatic venoocclusive disease. In 33 assessable patients, the overall response rate was 75% (complete response, one patient [3%]; partial response, 26 patients [72%]). With a median potential follow-up of 15 months, the mean duration of response was 9 months (range, 2 to 30 months). CONCLUSION: IHP with TNF and melphalan results in significant regression of bulky hepatic cancers confined to the liver in the majority of patients. Based on these initial results, further refinement of this treatment technique is warranted; perhaps by the combination of IHP with other regional treatment strategies to provide long-term control of unresectable cancers confined to liver.

Adult↗
PubMed1997

Estimation of mean exocytic vesicle capacitance in mouse adrenal chromaffin cells.

Whole-cell membrane capacitance measurements are frequently used to monitor neuronal and nonneuronal secretory activity. However, unless individual fusion events can be resolved, the type of the fusing vesicles cannot be identified in these experiments. Here we apply statistical analysis of trial-to-trial variations between depolarization-induced capacitance increases of mouse adrenal chromaffin cells and obtain estimates for the capacitance contribution of individual exocytic vesicles between 0.6 and 2 fF. For comparison, measurements of membrane capacitance were combined with amperometric recordings of catecholamine release during intracellular perfusion of chromaffin cells with high [Ca2+]. Crosscorrelation of both signals yielded a mean capacitance contribution of individual catecholaminergic vesicles of 1.3 fF. We suggest that depolarization-induced capacitance increases in mouse adrenal chromaffin cells mainly represent fusion of chromaffin granules.

Adrenal Glands↗
PubMed1997

Rapid exocytosis in single chromaffin cells recorded from mouse adrenal slices.

We report here that brief depolarizations such as action potentials trigger exocytosis in thin mouse adrenal slices. The secretory rates obtained in membrane capacitance recordings from chromaffin cells in slices are faster than those observed in isolated cells. Fast exocytosis in slices is attributable to the rapid release of a small pool of vesicles. The pool recovers from depletion with a time constant of 10 sec. Recruitment of the rapidly released vesicles is strongly hindered by the fast Ca2+ chelator BAPTA and much less by the slower chelator EGTA. We suggest that these vesicles are located in close proximity to Ca2+ channels. Spatial coupling of Ca2+ entry and exocytosis may be sensitive to cell isolation and culture.

Adrenal Medulla↗
PubMed1997

Surgical treatment for myeloma of the bone. A retrospective analysis of 22 cases.

In a retrospective study, 22 patients treated surgically for solitary or multiple myeloma between 1980 and 1993 were analysed. The main complaint was pain. A fracture was observed in 7 cases and motor-sensory impaired neurology due to spinal compression in 3. Apart from incisional biopsies, tumour resections, reductions (with and without stabilization by osteosynthesis) and endoprotheses were performed either at the extremities or on the spine. In addition, radiation and chemotherapy were included in the therapeutical concept. Early mobilization was achieved in all cases, and the 5-year survival rate (Kaplan-Meier method) was 48%. The results presented in this study demonstrate that a variety of surgical interventions can be of importance in the treatment of myeloma of the bone, ranging from biopsy or even curative resections in selected cases to endoprosthetic replacement. Thus, good functional results can be achieved and maintained over often long survival times.

Aged↗
PubMed1996

Tissue- and stage-specific activation of an endogenous provirus after transcription through its integration site in the opposite orientation.

Endogenous proviruses of the Moloney murine leukemia retrovirus (Mo-MuLV) are transcriptionally blocked in early embryos and in general remain silent even when the tissues have become permissive to the expression of newly integrated copies. Eventually, activation in presumably very few cells initiates rapid superinfection leading to viremia and leukemia, but the processes leading to provirus activation are unknown. Differences in the onset and development of viremia between several mouse strains carrying an endogenous Mo-MuLV (Mov lines) are attributed to a chromosomal position effect, but neither cell type nor stage of provirus activation is known for any strain. We have now monitored the appearance of viral transcripts and particles in the Mov13 strain, which carries the Mo-MuLV provirus in inverted orientation in the first intron of a collagen gene (Col1a1) with well-characterized transcriptional activity. We report obligatory tissue- and stage-specific virus activation in osteoblasts and odontoblasts. The significance of this activation pattern is indicated by the fact that of the great variety of cells expressing the wild-type collagen gene, only these two cell types can also transcribe the mutant allele including its viral insert. We propose that this transcription of the proviral genome, albeit in the opposite direction, leads to the activation of the viral promoter.

Animals↗
PubMed1995

Swelling-induced catecholamine secretion recorded from single chromaffin cells.

We have studied osmotically induced catecholamine secretion from bovine adrenal chromaffin cells by combining patch-clamp measurements, electrochemical detection of secretion, and Fura-2 measurements of intracellular free calcium concentration ([Ca2+]i). We find that osmotically induced catecholamine release is exocytotic and calcium dependent. Furthermore, we demonstrate that cell swelling is coupled to such secretion via a volume-activated current, carrying predominantly chloride, which causes a plateau depolarization of the cell membrane potential and thus promotes voltage-activated calcium influx. Therefore, cell volume changes may modulate the secretory activity.

Animals↗
PubMed1995

Sucrose reduces pain reaction to heel lancing in preterm infants: a placebo-controlled, randomized and masked study.

In term infants sucrose given by mouth has been reported to reduce duration of crying after a heel prick. This study was designed primarily to investigate the effect of sucrose administered orally immediately before heel lancing on the nociceptive reaction in preterm infants as assessed by change in heart rate and duration of crying. A secondary objective was to document changes in cerebral blood volume during acute pain. We used a randomized, masked, placebo-controlled, crossover trial in a neonatal intermediate care unit in a level 3 perinatal center. The patients studied were 16 preterm infants; birth weight, 900-1900 g; gestational wk, 27-34; corrected postmenstrual age at time of investigation, 33-36 wk. Each infant was assessed twice receiving 2 mL of sucrose 50% or 2 mL of distilled water in random order immediately before heel lance. Heart rate, thoracic movements, and transcutaneous blood gases were monitored continuously. Crying during the procedure was documented by a video-camera. A change in cerebral blood volume was assessed by near-infrared spectroscopy. We found the heart increased by a mean of 35 beats/min (bpm) after sucrose and 51 bpm after placebo (median difference 16 bpm, interquartile range 1-30 bpm, p = 0.005). Infants cried 67% of time after sucrose and 88% after placebo (median difference 10%, interquartile range 3-33%, p = 0.002). Cerebral blood volume decreased in 5 of 14 infants after sucrose and in 6 of 14 infants after placebo (difference not significant).

Administration, Oral↗
PubMed1994

Differential expression of AE1 in renal HCO3-secreting and -reabsorbing intercalated cells.

The cortical collecting duct of the kidney contains two types of intercalated cells that transport HCO3 in opposite directions. HCO3 reabsorption takes place in the alpha-type intercalated cells, which express a Cl/HCO3 exchanger on the basolateral membrane. This exchanger is the product of the anion exchanger 1 (AE1) or band 3 gene. HCO3 secretion occurs in the beta-intercalated cells, which have a Cl/HCO3 exchanger on the apical membrane. Based on studies in an immortalized cell line, recently it was proposed that the apical anion exchanger of beta-intercalated cells is also AE1 (van Adelsberg, J. S., Edwards, J. C., and Al-Awqati, Q. (1993) J. Biol. Chem. 268, 11283-11289). In the present study we reinvestigated this issue by determining the distribution of AE1 mRNA and protein in the two intercalated cell types using cells freshly isolated from the native epithelium. Using quantitative reverse transcriptase polymerase chain reaction, we found that alpha-intercalated cells, isolated from rabbit kidney by fluorescence-activated cell sorting, have high levels of AE1 mRNA, whereas beta-intercalated cells express very low levels. The ratio of AE1 mRNA levels in alpha- versus beta-intercalated cells averaged 10.1 +/- 2.6. In addition, metabolic acidosis increased the levels of AE1 mRNA by 3-5-fold in cortical collecting duct cells. This difference was confirmed by Northern blotting. Western blotting using an antibody against rabbit AE1 revealed a major immunoreactive product with a molecular weight of approximately 110 kDa in cortical collecting duct cells. Deglycosylation reduced the size of the immunoreactive product to approximately 90 kDa, which is compatible with the presence of a truncated form of AE1. Metabolic acidosis increased the intensity of the AE1 immunoreactive band. The level of AE1-immunoreactive protein was significantly higher in alpha-intercalated cells than in beta-intercalated cells. In aggregate, these data provide evidence for the differential expression of AE1 in HCO3-reabsorbing versus HCO3-secreting renal intercalated cells both at the mRNA and at the protein level. These results give no support to the concept that AE1 functions both as a basolateral and an apical anion exchanger in cortical collecting duct cells.

Acidosis↗
PubMed1994

[Perioperative antibiotic prophylaxis in orthopedics].

This study outlines the special connection between hip endoprosthesis implantation and the dangers of surgical infections. It surveys in detail the theoretical and practical aspects of perioperative antibiotic prophylaxis. On the basis of 85 cement hip prosthesis the author summarize the characteristics of the second generation Cephalosporins and give an account of their favourable results achieved by the use of Zinacef injection.

Adult↗
PubMed1992

Ten- to 14-year results of a ceramic hip prosthesis.

One hundred total hip arthroplasties with a cementless aluminum oxide socket and ball with different types of cemented metal femoral stems were performed from 1974 to 1979. All were primary implantations. These cases were recently reviewed in a ten- to 14-year follow-up evaluation. Despite extensive laboratory testing of the ceramic material, a significant number of cases resulted in a very unfavorable result such as extensive wear, ball fracture, or migration of the socket. Whereas the patients had died or could no longer be traced in the case of 23 prostheses, there were 25 prostheses that had already been exchanged at the time of review for mechanical reasons (two stem fractures, eight ceramic ball fractures) and for component loosening attributable to wear of the alumina components. The remaining 52 prostheses still in place had good clinical results in 80%. However, roentgenographic evaluation of these prostheses revealed signs of loosening in six femoral components and in three sockets. Migration of more than 5 mm was evident in 24 sockets (46% of surviving prostheses). Although this had caused loosening in only three sockets at the time of review, further migration up to the limits of the acetabular region would be a major reason for future failures.

Adult↗
PubMed1992

[Inability to mourn. Does the diagnosis hold up against an evaluation? On psychological processing of the Holocaust in Germany].

The book The Inability to Mourn by Alexander and Margarete Mitscherlich appeared in 1967 and claimed to provide a diagnosis of the era in which it was written. Superficially at least, its public impact was considerable. Rereading the work 25 years later, Tilmann Moser has profound misgivings as to the accuracy of the Mitscherlichs' diagnosis. He characterises the authors' approach as a mixture of analytic-cum-therapeutic, political and pedagogical attitudes and suggests that this was largely inappropriate to the task of identifying the actual psychic condition of the "generation of culprits" and of encouraging self-recognition and a disposition for change. Moser posits the "tragic paradox" that the people implicated in this crime require empathy if they are to genuinely break with the past.

Empathy↗
PubMed1991

[Arthroscopy in pediatric orthopedics].

Based on his own material, author for the first time in the Hungarian literature discusses the special points of arthroscopy in childhood and adolescence. Within a period of 18 months, 64 knee arthroscopies were performed on patients with the mean age of 14.9 years. In 17 cases arthroscopy was followed by surgical exposure of the joint, while 14 of the cases remained only diagnostic interventions. Arthroscopic intraarticular surgery was performed in 33 knees. Based on the analysis of the latter two groups it is stated that arthroscopy has its value in the fields of pediatric orthopaedics.

Adolescent↗
PubMed1987

[Clinico-anatomic studies of the carpal tunnel of the human hand].

Numerous investigations of the carpal tunnel were performed in 60 human hands of adults. In detail we determined the length, width, and thickness of the flexor retinaculum. Furthermore the dimensions of the carpal tunnel and the proximal, middle and distal cross-section areas were calculated. We found that the middle region is the narrowest portion of the carpal tunnel. The median nerve increases constantly in width from proximal to distal in the carpal tunnel whereas its thickness decreases. In 43.3% the nerve passes radially from the middle of the tunnel to the palm. In 21.7% the median nerve is located exactly under the middle of the flexor retinaculum and only in 1.7% is it shifted to the more ulnar side. The median nerve shows a winding course in the remaining cases.

Adult↗