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W Meyer

Publications and source records attributed to W Meyer.

At least 163 records · Page 9Linked to original sources
PubMed1995

[Psychophysical stress reactions during a psychoanalytic interview].

In 37 young volunteers analytically oriented interviews were taken and their effects being compared to those of conventional stressors using mental arithmetic. Because of their similarity to day-to-day stressors we expected higher cardiovascular reactions (blood pressure, heart rate and catecholamines) under interview situations than in mental arithmetic. Conforming this hypothesis, we found higher reactions in blood pressure regulation, while heart rates were not higher under interview situations compared to laboratory stressors. Epinephrine showed a qualitative difference: Only in interview situations we found a significant rise of 27%. Plasma cortisol also showed a rise in interview situations, however, smaller. We therefore suggest, that analytically oriented interviews are an adequate method to investigate cardiovascular reagibility in young hypertensive-prone persons.

Adult↗
PubMed1995

[Repeat liver resection in colorectal liver metastases].

For patients with recurrent operable liver metastases from colorectal cancer operative resection is the only chance of getting rid of their tumorous disease for a longer time. As there are not therapeutic alternatives more and more authors are reporting on repeated resections of liver metastases. From 1986 to 1994 we performed 12 recurrent liver resections with curative intent in 8 patients suffering from liver metastases of colorectal cancer: 4 synchronous and 4 metachronous metastases were removed, the primary procedure being anatomic hemihepatectomy in 5 cases and segmentectomy or bisegmentectomy in 3 cases. The mean time interval between the first and the second resections was 14 (4-23) months. Two patients underwent 4 consecutive liver resections because of recurrent metastases. In these cases the interval between the second, third and fourth procedures was 10 months. The postoperative complication rate was 16% and not a single patient died in hospital. Three patients died an average of 28 (9-54) months after the last liver resection, and the other 5 patients are still alive after an average of 14 (4-28) months: 3 are free of tumor and 2 have recurrent metastases in the liver. Compared with untreated or only locally treated cases, patients in whom operative risk is low can achieve prolonged survival times after resections of colorectal metastases to the liver.

Adult↗
PubMed1995

[Reactions to cardiopulmonary resuscitation: a study on emotions and communication behavior of the resuscitating physician].

Reactions of 20 physicians to cardiopulmonary resuscitation were examined by describing their emotions and communication in over 260 situations of resuscitation. All actions of physicians being helpful for the relatives in their grief change physicians' emotions after resuscitation. Though denial helps the physicians in confrontation with the relatives, it also seems to impair their emotional coping. Coping strategies of physicians are quite different: Young physicians show a pattern of emotional denial and activity in their resuscitation behaviour. Doctors being more experienced tend to deny less in this sense. Physicians with recent loss seem to cope very little emotionally. Active resuscitation behaviour results after resuscitation in being relieved for a short time, but coping is impaired because of the activity pattern. Speaking after resuscitation seems to improve coping.

Adaptation, Psychological↗
PubMed1995

Characterization of the phosphodiesterase inhibition by 2-(3-methoxy-5-methylsulfinyl-2-thienyl)-1H-imidazo-(4,5-c)-pyridine HCl and its sulfide- and sulfone derivatives in myocardial preparations from failing human hearts.

The effects of HN-10200 (2-(3-methoxy-5-methylsulfinyl-2-thienyl)-1H-imidazo(4,5-c)-pyridine HCl) and its derivatives HN-10201-sulfide and HN-10202-sulfone on the activities of the phosphodiesterase (PDE) isoenzyme activities isolated from ventricular myocardium of failing human hearts (end-stage myocardial failure, NYHA IV) were investigated. Four PDE isoenzymes (PDE I-IV) were separated by DEAE-sepharose chromatography. Milrinone, 3-isobutyl-1-methylxanthine (IBMX), and a derivative of pimobendan (2-(4-hydroxyphenyl)-5-(5-methyl-3-oxo-4,5-dihydro-2H-6-pyridazinyl)- benzimidazole HCl, PiD) were studied for comparison. Furthermore, the influence of HN-10200 on force of contraction and cAMP content of ventricular trabeculae of these hearts were determined. HN-10200 inhibited the activities of PDE I-IV concentration-dependently. The IC50 values were (mumol/l): 218.7, 283.1, 119.6, and 85.8 for PDE I-IV, respectively. The IC50 values of its derivatives were in the same range, i.e. the parent compound or its derivatives inhibited the PDE isoenzymes nonselectively. IBMX also inhibited PDE I-IV nonselectively, but was about ten times more potent based on IC50 values. In contrast, PiD was the most selective and potent PDE III inhibitor tested. Milrinone inhibited both, PDE III and IV, up to two orders of magnitude more potently than PDE I and II, HN-10200 (30 mumol/l) only marginally and insignificantly increased force of contraction and cAMP content of the ventricular trabeculae. Thus, HN-10200 and it's derivatives HN-10201-sulfide and HN-10202-sulfone are nonselective inhibitors of myocardial PDE I-IV. HN-10200 revealed only neglectable positive inotropic effects in preparations from failing human heart.

1-Methyl-3-isobutylxanthine↗
PubMed1995

Immunohistochemical demonstration of adenohypophyseal hormones during postnatal ontogenesis in the Gray Short-tailed Opossum, Monodelphis domestica (marsupialia).

Antibodies against human FSH, LH, TSH, ACTH, GH, PRL, and MSH were applied to paraffin sections of newborn (< 1) and pouch-young individuals with the age of 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 13, 14 days, respectively (D1, D2,...). In the pouch-young, the antibody reactions occurred only in the pars distalis of the adenohypophysis. The D < 1 individuals included, the reactions were strong for ACTH, moderate/strong for GH, and moderate for MSH. Reactivity for TSH was recorded first in D2 specimens, for LH in D3 animals, for FSH and PRL in D8 animals. There was a remarkable regional distribution of reactive cells within the pars distalis: reactions for ACTH were localized mainly in the rostral area, those for GH were most prominent caudally. The chronological sequence of appearance of the specific hormone-producing cells in the pouch-young generally is in accordance with the characteristic pattern known in other mammalian species. The late onset of differentiation of some cell types indicates the research possibilities that postnatal Monodelphis domestica can offer in the field of ontogenetic studies on the mammalian endocrine system.

Animals↗
PubMed1995

Remarks on specific adaptive scale structure of the hair cuticle in some European bats.

Specific regional variation of scale structure of the hair cuticle was demonstrated by scanning electron microscopy in five vespertilionid bat species. Only the tip region of hairs here showed unequal hastate coronal scales with long free parts (blades), and free edges that were distinctly dentate or narrow lobate. This regional peculiarity of the hairs could be explained as an adaptive help to maintain a turbulent boundary layer of air around the body to aid hovering or gliding flight.

Adaptation, Physiological↗
PubMed1994

Phase I study of recombinant interleukin-1 beta in patients undergoing autologous bone marrow transplant for acute myelogenous leukemia.

A phase I trial was conducted with recombinant human interleukin-1 beta (rhIL-1 beta) in patients undergoing autologous bone marrow (BM) transplantation for acute myelogenous leukemia. rhIL-1 beta was administered at 3 dose levels (0.01, 0.02, 0.05 microgram/kg) by 30 minute intravenous infusion once a day beginning on the day of BM infusion and continuing for a total of 5 doses. A total of 17 patients were entered on the trial, and their results were compared with those of 74 consecutive historical control patients that did not receive colony stimulating factors. Moderate toxicity was observed in all patients. All 17 patients developed fever and chills within 30 minutes after initiation of rhIL-1 beta, and hypotension was observed in 14 of 17 patients 5 to 8 hours after the infusion. A total of 30% of patients required therapy (normal saline or dopamine) for treatment of hypotension. Therefore, dose escalation was discontinued at the 0.05 microgram/kg dose level. The number of days required to achieve an absolute neutrophil count greater than 500 mL in patients who received rhIL-1 beta was less than in historical patients (25 v 34; P = .02). This appeared to correlate with a reduced incidence of infection between days 0 and 28 after BM infusion (12% v 23%; P = .049). Median bilirubin, median creatinine, platelet recovery, and days in the hospital were not different between study patients and historical controls. Survival of patients who received rhIL-1 beta compared with that of historical patients was improved (30% v 20%; P = .04). These possible benefits were achieved at the cost of moderate toxicity during rhIL-1 beta administration.

Adolescent↗
PubMed1994

NADPH diaphorase (nitric oxide synthase) in the central nervous system of spiders (Arachnida: Araneida).

The distribution of NADPH diaphorase (nitric-oxide synthase) in the CNS of spiders was determined in 10 species of five families, applying enzyme histochemical technique on sections of fresh frozen, unfixed material. Positively reacting cells could be found only in the peripheral neuropil and along internal and external lamellae of all species studied. These cells were numerous and showed long and widespread arborizations in the ventral cord of orthognath species. The results obtained are discussed in view of possible glial functions of such cells and the relation of nitric oxide to other neurotransmitters in the condensed brain of the Araneida.

Amino Acid Oxidoreductases↗
PubMed1994

Laparoscopic drainage of a lymphocele after renal transplantation.

Lymphoceles are a well-known complication of renal transplantation, with incidence rates up to 18%. The management of symptomatic lymphocele remains controversial. We report the case of a lymphocele which was successfully drained into the peritoneal cavity using laparoscopic surgery.

Drainage↗
PubMed1994

Fingerprinting reveals gamma-ray induced mutations in fungal DNA: implications for identification of patent strains of Trichoderma harzianum.

We have analyzed different patent strains and gamma-ray induced mutants of Trichoderma harzianum by DNA fingerprinting and PCR fingerprinting (RAPD). Applying wild-type phage M13 DNA, with the oligonucleotides (CT)8 and (GTG)5 as probes for hybridization, as well as the oligonucleotides GGCATCGGCC, (GTG)5, (CAC)5 and the M13 sequence GAGGGTGGCGGTTCT as primers in PCR, we were able to obtain different and discriminative fingerprint patterns for all strains and mutants investigated. Irradiation of fungi led to mutations which resulted in new fingerprint patterns. Consequently, irradiation-induced mutants can be clearly distinguished from the original wild-type isolates by genomic fingerprinting which is of importance for the patent protection of fungal strains. Sequencing of the ITS-1 and ITS-2 regions of the rDNA gene complex revealed the same sequence for all mutant strains and the original wild-type strain.

Base Sequence↗
PubMed1994

Comparison of binding affinity of oxytocin antagonists to human and rat uterine oxytocin receptors and their correlation to the rat uterine oxytocic bioassay.

One of the primary methods used to screen the development of oxytocin antagonists (OTAs) is the rat oxytocic bioassay. The purpose of this study was to determine whether the rat oxytocic bioassay is a good predictor of binding affinity to human and rat uterine oxytocin receptors (OTr). The binding affinities of five OTAs to human and rat uterine OTr were determined and correlated with pA2 values derived from the rat uterine oxytocic bioassay. Human uterine myometrial tissue was obtained from patients at the time of cesarean section. Rat uterine tissue for the OTr assay was taken at Day 21 of pregnancy. OTr assays were accomplished by isolating uterine cell membranes and performing saturation analysis with cold OTAs and tritium-labeled oxytocin. The association constants (Ka; 10(+8)/M) were calculated by nonlinear curve-fitting techniques. The Ka for the five OTAs (Mpa1-OT, Antag I, L366948, Antag II, and Antag III), as estimated from the human OTr assay, were 0.55, 0.60, 2.27, 1.91, and 47.20, respectively. Ka estimates obtained through use of rat uterine membranes were 0.51, 1.16, 5.89, 2.03, and 24.40, respectively. Correlation of the log10 of the rat oxytocic bioassay results with those of the rat and human OTr assay was 0.94 and 0.98, respectively (p < 0.01). Antag III was approximately 55, 48, and 90 times more potent than Mpa1-OT as determined by the rat bioassay and rat and human uterine OTr assays, respectively. Mpa1-OT is an OTA that is currently undergoing clinical evaluation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Nitrovasodilator-induced relaxation and tolerance development in porcine vena cordis magna: dependence on intact endothelium.

1. Isolated segments of porcine vena cordis magna exhibited a reproducible contractile activity upon application of prostaglandin F2 alpha (PGF2 alpha) or KCl, that was independent of the presence of intact endothelium. Substance P (3 nM) elicited strictly endothelium-dependent relaxations amounting to 46.1 +/- 1.4% (n = 206) of contractions induced by 10 microM PGF2 alpha. 2. S-nitroso-N-acetyl-D,L-penicillamine (SNAP), a compound that spontaneously liberates nitric oxide, concentration-dependently relaxed PGF2 alpha-precontracted (50 microM) venous segments. Tolerance induction (incubation with 100 microM SNAP for 30 min) within the same segments resulted in a 3 fold attenuation of this effect, which was not further reduced after additional preincubation with glyceryl trinitrate (GTN). Removal of endothelium or the presence of N omega-nitro-L-arginine methylester (L-NAME) significantly improved the potency of SNAP before and after tolerance induction. 3. Concentration-dependent relaxations induced by GTN in non-tolerant veins were similar in the presence and absence of endothelium but much more reduced in tolerant endothelium-denuded (75 fold) compared to intact (20 fold) segments. In contrast, the presence of L-NAME significantly improved GTN-activity solely in non-tolerant veins, which, therefore, also resulted in a more pronounced attenuation of activity due to tolerance induction (100 fold). Preincubation of intact veins with SNAP also reduced GTN-activity but to a lesser extent (10 fold). 4. The more delayed but much longer, and compared to GTN somewhat weaker, acting new nitrovasodilator N-(3-nitrato-pivaloyl)-1-cysteineethylester (SPM 3672) was more potent in denuded than intact non-tolerant venous segments. Induction of tolerance by GTN resulted in a 2 fold-attenuation of potency. This effect was increased to 15 fold in denuded veins but solely due to enhanced potency of SPM 3672 caused by removal of endothelium.5. These data demonstrate that intact endothelium of porcine vena cordis magna attenuates the relaxant potency of nitrovasodilators but also probably participates in vascular bioactivation of GTN.We suggest that the reduced potency of nitrovasodilators is due to endogenous production of nitricoxide, which may affect the soluble guanylate cyclase/cyclic GMP-system or inhibit nitrate bioactivation pathways.

Animals↗
PubMed1994

Morphogenesis of the osteo-architecture in the carnassial region of the feline mandible, as demonstrated by microfocal radiography.

For the first time, osteogenesis was observed using direct magnifying microradiography, a noninvasive technique that has a high power of resolution. Thus, it was possible to correlate different stages of bone maturation in the feline mandible with specific functional demands. Our observations suggest a relationship between osseous structure and the mode of feeding and content of the diet.

Animals↗
PubMed1994

Effects of temperature and sodium on myocardial and hepatocellular fatty acid uptake.

Fatty acid influx into human myocardium was studied in 15 patients during the cooling phase of cardiopulmonary bypass at myocardial temperatures of 37 degrees to 25 degrees C. The fitting of the data to a functional relation, developed in this study, revealed fatty acid influx to be a temperature-dependent saturable process corresponding to a Michaelis-Menten constant (Km) at 37 degrees C of 0.26 +/- 0.084 mumol/g, a maximal fatty acid influx velocity (Vmax) at 37 degrees C of 0.28 +/- 0.045 mumol/g per minute, activation energy for fatty acid binding to the putative carrier (E) of 23.8 +/- 5.6 kcal/mol, and a free energy for conformational change of the carrier (U) of 10.9 +/- 8.0 kcal/mol. In short-term cultured hepatocytes, Km increased in the absence of Na+ from 171 +/- 48 to 301 +/- 71 nmol/L, and Vmax of [3H]oleate decreased from 1063 +/- 69 to 847 +/- 68 pmol/min per milligram protein. The fitting of these data to a functional relation revealed a transmembrane potential-dependent component of parameters E and U to be -0.479 and -0.374 kcal/mol, respectively. It is proposed that for fatty acid influx a protonated fatty acid form is preferred that consists of a Na+ complex with the mesomeric form of nondissociated fatty acid from which Na+ and H+ are released during collision with the carrier.

Animals↗
PubMed1994

Phase I study of oral etoposide in children with refractory solid tumors.

PURPOSE: To determine the maximum-tolerated dose (MTD), dose-limiting toxicity, and plasma concentrations of orally administered etoposide (VP-16) in pediatric oncology patients. PATIENTS AND METHODS: In a phase I study, 20 children with refractory solid tumors received oral VP-16 (the intravenous preparation diluted with sodium chloride) three times daily for 21 days. Daily dose levels studied were 50 mg/m2 (n = 5), 60 mg/m2 (n = 7), and 75 mg/m2 (n = 8). VP-16 concentrations were measured in blood samples collected on days 1, 7, 14, and 21. RESULTS: Grade 3 to 4 thrombocytopenia and/or neutropenia causing interruption of the 21-day course or persisting for more than 7 days after the last day of chemotherapy was seen at all dose levels, but was not dose-limiting. One patient treated at the 50-mg/m2 daily dose died of sepsis. At the 75-mg/m2 dose level, diarrhea was dose-limiting. Estimated plasma VP-16 concentrations were greater than 1 micrograms/mL for median periods of 9.4, 15.4, and 13.5 hours per day at daily doses of 50, 60, and 75 mg/m2, respectively. Responses were observed in seven of 14 patients who received at least one additional course of etoposide after a rest period of 7 days. There was one complete and two objective responses. Four patients were considered to have stable disease. CONCLUSION: The intravenous preparation of VP-16 administered orally appears to be well tolerated by heavily pretreated pediatric patients. On the three-times daily, 21-day schedule, a daily dose of 75 mg/m2 exceeds the MTD, with diarrhea as the dose-limiting toxicity. The recommended dose for oral etoposide is 60 mg/m2/d administered every 8 hours.

Administration, Oral↗