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Biomedical subjects

W Kuhn

Publications and source records attributed to W Kuhn.

At least 307 records · Page 17Linked to original sources
PubMed1988

Angiotensin II/III and substance P in human follicular fluid obtained during IVF: relation of the peptide content with follicular size.

Ovarian follicular fluid (FF) of a number of species contain regulatory peptides secreted by granulosa cells or by autonomic nerve terminals. In this report we demonstrate the presence of authentic (HPLC-verification) angiotensin II and III as well as of substance P (SP) in human FF obtained from hMG stimulated infertile patients undergoing in vitro fertilization. Angiotensin II/III (AII/III), estradiol (E2) and progesterone concentrations increase with the size of the follicles. SP concentrations did not vary significantly in FF of various sizes. These peptide concentrations in FF are about 10-fold higher than those measured in the serum of the same patients. Attempts to correlate SP, AII/III, E2 and progesterone concentrations in the individual FF with the ability of an oocyte to be fertilized, failed. Neither AII/III, SP, E2 nor progesterone concentrations were different in these subclasses of FF. Follicles of patients punctured under general anesthesia contained significantly more SP than follicles of patients which had lumbar analgesia. AII/III concentrations were the same in FF of both treatment groups. The presence of angiotensin II and III in FF in increasing concentrations depending on the maturity of the follicle and the inability of general anesthesia to affect the AII/III concentrations suggests that this peptide is produced within the ovary.

Anesthesia, General↗
PubMed1988

4,4-Diphenylpiperidine derivates and their sila analogues. A comparative study of their interaction with neural receptor biding sites and synaptosomal monoamine uptake.

The potential anti-Parkinson drugs 1-R-4,4-diphenylpiperidines and 1-R-4,4-diphenyl-4-sila-piperidines (R = H, CH3, i-propyl and t-butyl) were evaluated for their neuroreceptor affinity with respect to their structure-activity relationship. In these compounds substitution of the central carbon at position 4 by a silicon leads to more lipophilic substances. While the binding of these compounds to dopamine, serotonin and gamma-aminobutyric acid/benzodiazepine receptors is relatively non-specific, the binding to the mu- and delta-subtypes of opiate receptors and to the 1-methyl-4-phenyl-1,2,3,6-tetra-hydropyridine receptor binding site show probably pharmacologically relevant effects. In almost all cases the sila-compounds have a slightly higher receptor affinity than the corresponding carbon-compounds. The studies on the uptake sites for the biogenic amines noradrenaline, dopamine and serotonin, on the other hand, reveal some considerable differences between the carbon- and silicon-containing analogues. The 4,4-diphenyl-4-sila-piperidine has much stronger uptake inhibiting properties for noradrenaline and serotonin than the corresponding carbon compound.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1988

Collagenase activity in cervical tissue of the non-pregnant and pregnant human cervix.

Collagen degradation has been suggested to play an important role in the process of cervical ripening at term. After giving informed consent tissue samples were taken from the posterior lip of 10 non-pregnant women of child-bearing age, 10 women having a termination of pregnancy at 9-12 weeks' gestation and 12 women who had had normal spontaneous deliveries at term. Collagenase activity was measured by a specific technique using native, triple helical collagen. Proteolytic activity was determined with commercially available 14C-methaemoglobin as substrate. For identification of collagen fragments SDS-polyacrylamid-gel-electrophoresis was performed using a modified Laemmli-technique. Collagenase and protease activity were found in all extracts of the different groups. There was a marked increase in enzymatic activities in the postpartum tissue samples suggesting that significant collagen breakdown had taken place. The absence of typical collagen fragments in the SDS-electrophoresis seemed to be due to a very rapid further degradation of the fragments by proteases into small peptides which then readily left the cervix. The present findings confirm the essential role of proteolytic enzymes in cervical dilatation at term.

Adult↗
PubMed1988

Colonic lesion expert system. Performance evaluation.

A computer-based expert system for diagnosing colonic sections as normal, adenoma or adenocarcinoma is described, along with an evaluation of its performance. On the basis of its knowledge base, consisting of the values of diagnostic clues and their associated certainty factors for the possible diagnoses, the system will suggest the diagnosis for new cases presented to it. Using the data provided for 16 diagnostic clues, the system arrived at correct diagnoses for all cases of normal colon, for 49 of 50 cases of adenoma and for 48 of 49 cases of adenocarcinoma. Sample outputs from the expert system are presented and discussed, and the effects of possible alterations in the data base are considered.

Adenocarcinoma↗
PubMed1987

Angiotensin I converting enzyme in cerebrospinal fluid of patients with neurological diseases.

The angiotensin I converting enzyme activity (kininase II, EC 3.4.15.1) was measured fluorimetrically in cerebrospinal fluid (CACE) of 154 patients with neurological disorders and 27 controls. The concentrations of total protein, albumin, and immunoglobulins G and A were also determined. There was no correlation between CACE and sex or age, but a slight positive relation between CACE and total protein and an inverse correlation between CACE and albumin were observed. Compared to controls, significantly elevated CACE was found in acute untreated CNS sarcoidosis (P less than 0.0001), followed by viral encephalitis, CNS syphilis, Huntington's disease, and multiple sclerosis (P less than 0.001). In treated CNS sarcoidosis, only a minor increase of CACE was observed (P less than 0.05). The determination of CACE can be used for the diagnosis of neurological disorders.

Central Nervous System Diseases↗
PubMed1987

The in vivo contour plot. An improved representation of stimulus experiments.

The in vivo contour plot is a superior representation of the data from stimulus experiments. Its performance is illustrated by four examples, viz., necrosis of a superfused rat heart, anoxia on perfused mouse liver, ischemiae on Langendorff heart in the presence and absence of a Ca antagonist, and the internal stimulus of the cardiac cycle. The in vivo contour plot visualizes line intensities (metabolite concentrations), line positions (pH), and linewidths, as well as the time derivatives of these parameters in any available number of spectra.

Animals↗
PubMed1987

Collagen degradation in the pregnant human cervix at term and after prostaglandin-induced cervical ripening.

The role of enzymatic collagen degradation in prostaglandin-induced and physiological cervical ripening was studied by determining collagenase and other proteolytic activity in extracts of cervical biopsies. Collagenase activity was assayed in a highly specific and sensitive system using native collagen type I as substrate. The intracervical application of sulprostone gel prior to termination of 1st trimester pregnancy led to a marked improvement in cervical dilatability. Collagenase and proteolytic activity were found to be significantly higher in postpartum samples than in specimens obtained from the nonpregnant or early pregnant cervix. After sulprostone treatment enzymatic activities were only marginally elevated. Analysis of extractable peptides showed that sub partu collagen was degraded in preference to noncollagenous proteins into very small fragments, whereas in the process of prostaglandin-induced cervical ripening collagen degradation appears to be of minor importance.

Cervix Uteri↗
PubMed1987

The role of collagenases and proteases in prostaglandin-induced cervical ripening.

Tissue samples were taken from the posterior lip of the cervix of 10 non-pregnant women, 10 women having a termination of pregnancy at 9-12 weeks' gestation and 16 women having a termination who had had an intracervical application of either 50 micrograms sulprostone gel or 2 ml 5% tylose 8-12 hours previously. The efficacy of cervical priming was demonstrated objectively by tonometric measurements. Collagenase activity was determined by a new highly specific technique using native, triple helical collagen. Protease activity was measured by a modified Anson-test. For identification of collagen fragments SDS-polyacrylamide electrophoresis was done on the acetic acid soluble fractions. The sulprostone gel induced effective cervical ripening in all of the patients. Collagenase and protease activity were found in all extracts from the different groups, however, PG-pretreatment of the cervix led to no significant increase in enzymatic activities. In addition, the absence of typical collagen cleavage products in the SDS-electrophoresis suggested that no significant collagen breakdown had occurred. In contrast to previously published literature we conclude that enzymatic collagen degradation does not play a predominant role in PG-induced cervical ripening.

Abortifacient Agents, Nonsteroidal↗
PubMed1987

[Facilitating cervix dilatation of the non-pregnant uterus by intracervical administration of gels containing prostaglandin and calcium chloride].

In a prospective, randomised study, 50 non-pregnant patients were treated intracervically with 3 ml 5% tylose, 50 micrograms sulprostone, 100 micrograms sulprostone gel, 3 ml 2.5 mM or 9.0 mM calcium chloride gel in order to soften the cervix 12-14 hours before diagnostic curettage. The gel was not used in a further 20 patients. To objectively demonstrate the priming effect, the force required for dilatation of the cervical canal was measured in Newtons, using a mechanical tonometer both before gel application and before the operation. In comparison with the administration of tylose only, the intracervical application of either sulprostone gel or calcium chloride gel led to a significant improvement in cervical dilatability. Tylose alone had a slight but measurable effect on the cervix. An increase in sulprostone from 50 micrograms to 100 micrograms or calcium molarity from 2.5 mM to 9.0 mM brought no further improvement in the dilatory effect. Dilatation-induced cervical lesions could be avoided by preoperative cervical ripening. After application of sulprostone, 3 out of 20 patients experienced doses-dependent uterine cramps, while all patients treated with calcium chloride gel were free of side effects. The intracervical administration of sulprostone and calcium chloride gel allowed gentle dilatation of the non-pregnant cervix, thus lowering the risk of uterine lesions. Under clinical aspects, cervical priming facilitates diagnostic and therapeutic procedures, which, in exceptional cases, can be performed without anaesthesia.

Administration, Intravaginal↗
PubMed1987

Medroxyprogesterone acetate and lipid metabolic changes.

Lipid metabolic changes under oral treatment with medroxyprogesterone acetate (MPA) were investigated in four groups of patients: group I; 10 patients aged 25-45 (mean 38) years received 50 mg MPA daily for pelvic endometriosis. Group II; 21 patients aged 55-77 (mean 62) years received 200 mg MPA daily for surgically treated endometrial carcinoma stage I. Group III; 14 praemenopausal patients aged 37-52 (mean 47) years received 1000 mg MPA daily for metastasized breast cancer. Group IV; 27 post-menopausal patients aged 53-78 (mean 68) years were treated with 1000 mg MPA daily for metastatic breast cancer as well. A fifth group of initially 86 patients aged 40-86 (mean 63) years after surgery for endometrial carcinoma stage I served as untreated control for groups II and IV. Cholesterol and triglyceride concentrations were measured enzymatically lipoproteins were determined by quantitative electrophoresis and precipitation and apolipoproteins A1 and B were quantified by kinetic rate nephelometry. Whereas in patients of group I no changes of lipid and lipoprotein parameters were observed, daily oral doses of 200 mg MPA and more led to a marked fall in alpha-lipoprotein-, HDL-cholesterol and apolipoprotein A1 levels. beta-Lipoprotein-, LDL-cholesterol and apolipoprotein B concentrations rose significantly in Groups III and IV. The relevance of these findings in terms of athero-genicity is discussed.

Adult↗
PubMed1987

The effect of R-(-)-deprenyl in de novo Parkinson patients on combination therapy with levodopa and decarboxylase inhibitor.

The effectiveness and tolerability of deprenyl as an adjunct in the therapy of parkinsonism were studied in a double-blind trial comprising 30 de novo patients. Quantification was based on the Columbia University Rating Scale, the SCHOPPE Motor Performance Series, as well as Zung's Scale. The results were evaluated using a response score. Two thirds of the cases that could be evaluated showed a statistically significant improvement while on adjuvant deprenyl therapy. One third of the patients showed no improvement or worsened. Using the Motor Performance Series, the improvements are most clearly shown in the replugging test, which is the best measure of the patient's ability to perform complex movements. This means that deprenyl is particularly useful in improving the akinesia-rigor syndrome. This study suggests that early combination of levodopa with deprenyl is superior to treatment with levodopa alone.

Benserazide↗
PubMed1986

Observation of Mg2+.ATP and uncomplexed ATP in slow exchange by 31P-NMR at high magnetic fields.

The 31P-NMR lines of the beta-phosphate groups in Mg2+.ATP and in metalfree ATP can be observed separately up to 280 K at 8.5 T and up to 285 K at 11.7 T. At 274 K and 8.5 T the beta-phosphorous resonances are in slow exchange at pH values above pH 5, the gamma-phosphorous resonances are in slow exchange only near pH 6, but in fast exchange at low and high pH-values. The fast exchange condition holds for the alpha-phosphorous resonances over the entire pH-range. For Ca2+.ATP and metalfree ATP always fast exchange prevails down to the freezing point of water even at 11.7 T. Based on the separate observation of the 31P-NMR signals of Mg2+.ATP and uncomplexed ATP new experiments are proposed and possible sources of error in 'in vivo' NMR studies are discussed.

Adenosine Triphosphate↗
PubMed1986

[Current aspects of therapy of ovarian cancer. Surgical therapy of epithelial ovarian cancer at the Göttingen University Gynecologic Clinic. A retrospective analysis of 82 patients 1981-1984].

The most important step in the treatment of epithelial ovarian carcinoma is radical surgery which should be as radical as possible, since this can exercise a decisive influence on the effectiveness of subsequent chemotherapy or radiotherapy. During 1981-1984 98 patients with an ovarian carcinoma were operated upon. 82 of these patients had epithelial tumours that will be discussed in the article. The mean age was 59.9 years. 88% of the patients were additionally at risk by one or several risk factors. Surgical approach was standardised: longitudinal incision, hysterectomy, adenectomy, resection of omentum and, if necessary, maximum possible removal of the peritoneum of the pelvis. In 28 cases additional surgery became necessary at the intestine. 77% of the patients (n = 63) were in the advanced stages FIGO III and IV. In 50 patients the operation lasted for up to 4 hours, in 24 up to 6 hours and in 8 for more than 6 hours. Intraoperative complications occurred in 37% (twice lesion of the ureter, in 5 cases intestinal lesion, in 23 cases anaesthesiological problems due to preexisting risks). In stages I and II reduction of tumour size below 2 cm was achieved in 100% of the cases, in stage III in 87.5%, in stage IV in 45%. Two patients died postoperatively. The postoperative complication rate was 48%. Almost 30% of these were represented by cardiopulmonary disturbances. Although the percentage appears high, most of the problems were well manageable, so that the patients could be transferred to follow-up therapy within 2-3 weeks. For type of follow-up therapy, tumour response.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1986

Rhomboid flaps in surgery for decubital ulcers: indications and results.

Fasciocutaneous or musculocutaneous flaps have greatly enlarged the scope of surgical possibilities for repairing a decubital ulcer. In paralyzed patients, however, one must always reckon with recurrences, so larger flaps, which are often prone to complications, should be saved for possible recurrence. The use of muscle flaps in partially paralyzed patients or in patients recovering from neurological injury may lead to functional loss. The Limberg (rhomboid) flap is a very reliable surgical method in which the donor site and the associated tension in tissue lie outside the weight-carrying areas; the donor site lies in the perineal area, which is never used for other flaps. Our experience is presented with 23 Limberg flaps in 21 patients in a series of 103 operated decubital ulcers in 73 patients.

Adolescent↗
PubMed1985

[Cervix ripening and labor induction in therapeutic abortion in the middle and late 2d trimester using intracervical and extra-amniotic prostaglandin gel administration].

In 64 patients for therapeutic abortion between the 17th to 26th week of pregnancy abortion was induced with a standardized two-step procedure. After priming of the cervix with intracervical application of prostaglandin gel, labour was induced with extraamniotic PG-administration under epidural anaesthesia. The priming effect was demonstrated objectively in 10 patients with a mechanical tonometer. Prostaglandin F2 alpha, PGE2 and sulprostone were used in the study. There were no significant differences in the total length of therapy (cervix priming time plus induction of labour to abortion interval) between the three groups of patients. Except for 4 patients who required an instrumental extraction of the fetus, abortion occurred in all the patients within a total time of 30 hours (93.8%). The mean induction of labour to abortion interval was 8.3 hours (range: 1.0 to 17.3 hours) in all patients and there was, again, no significant difference between the three groups. Epidural anaesthesia gave a painless induction of abortion in 60 out of 62 patients, while 2 patients required additional analgesics. In 2 patients epidural anaesthesia was contraindicated. In contrast to the systemic administration of PG the incidence of gastrointestinal side effects was low (10.9%). In one case a cervical lesion was observed due to a tenaculum laceration. Although there was no general antibiotic prophylaxis endometritis occurred in only 3 cases (4.7%). The combination of intracervical PG gel for cervical priming, extraamniotic PG gel for labour induction and epidural anaesthesia presents a gentle and efficient method for the termination of pregnancy in the middle to late second trimester.

Abortifacient Agents, Nonsteroidal↗
PubMed1985

Cervical ripening and induction of labor by intracervical and extra-amniotic prostaglandin gel application in cases of intrauterine fetal death.

In 42 patients with intrauterine fetal death between the 29th and 43rd week of gestation, a standard, 2-step procedure was employed to deliver the dead fetus. After priming with an intracervical application of PGF2 alpha- or PGE2-gel, labor was induced by extra-amniotic prostaglandin (PG) gel or oxytocin infusion while under epidural anesthesia. Intracervical PG application led to a significant improvement in the modified Bishop score from 1.3 to 7.6 after a mean of 8 h. In 20 patients labor and progressive dilatation of the cervix occurred after intracervical PG gel application alone. The average total therapy time was 18.1 h in patients treated with PGF2 alpha and 13.7 h in the PGE2-treated group. The average induction of labor to delivery intervals were 8.8 h in the PGF2 alpha- and 7.1 h in the PGE2-group. Gastrointestinal side effects were observed in only 5 patients. The combination of cervical ripening with intracervical PG gel application and induction of labor by extra-amniotic PG gel under epidural anesthesia is an efficient and safe method for treatment of intrauterine fetal death.

Adolescent↗