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Biomedical subjects

M Franz

Publications and source records attributed to M Franz.

At least 109 records · Page 6Linked to original sources
PubMed1993

Effects of canine myocardial infarction on sympathetic efferent neuronal function: scintigraphic and electrophysiologic correlates.

We studied the effects of nondecentralized left stellate ganglion stimulation on regional epicardial monophasic action potential duration at 50% (APD50) and 90% (APD90) repolarization from 104 sites in 10 surviving dogs with a chronic myocardial infarction model. These effects were correlated with thallium-201 and iodine-123 metiodobenzylguanidine (MIBG) imaging to identify areas of viable but denervated myocardium. Mean infarct size was 5.2% +/- 0.8% total heart weight, and the planimetered areas of denervation were always larger (18% +/- 4% total heart area). During constant ventricular pacing, stellate stimulation tended to shorten the APD90 only in normally innervated areas (364 +/- 5 to 358 +/- 5 msec) and to increase in denervated areas (358 +/- 5 to 362 +/- 5 msec), (p value not significant (NS) for prestellate and poststellate stimulation; p < 0.05 for difference between denervated vs innervated). The APD50 significantly shortened in innervated areas from 287 +/- 5 to 270 +/- 3 msec (p < 0.05) compared with denervated areas (283 +/- 4 to 274 +/- 5 msec, p = NS). We conclude that MIBG imaging demonstration of denervation identifies areas with impaired shortening of the epicardial APD50 in response to stellate stimulation and that nontransmural myocardial infarction produces areas of denervation larger than areas of necrosis.

Action Potentials↗
PubMed1993

Trinucleotide repeat length instability and age of onset in Huntington's disease.

The initial observation of an expanded and unstable trinucleotide repeat in the Huntington's disease gene has now been confirmed and extended in 150 independent Huntington's disease families. HD chromosomes contained 37-86 repeat units, whereas normal chromosomes displayed 11-34 repeats. The HD repeat length was inversely correlated with the age of onset of the disorder. The HD repeat was unstable in more than 80% of meiotic transmissions showing both increases and decreases in size with the largest increases occurring in paternal transmissions. The targeting of spermatogenesis as a particular source of repeat instability is reflected in the repeat distribution of HD sperm DNA. The analysis of the length and instability of individual repeats in members of these families has profound implications for presymptomatic diagnosis.

Adult↗
PubMed1993

[Epidemiologic findings of the etiology of psychogenic diseases].

In an epidemiological longitudinal field study, a sample of high risk probands suffering from medium psychogenic impairment was investigated with regard to the etiological relevancy of factors influencing psychogenic disorders (psychoneuroses, character neuroses, psychosomatic and/or psychosomatic functional diseases). The study focused the question of the etiological impact of personality, life events, and social support. With theoretical reference to the psychodynamic concept of personality trained physicians and psychologists investigated 240 probands in a half standardized psychodynamic interview which included psychometric and social empiric instruments. Expert ratings and self ratings were used to assess the current psychogenic impairment. The impact of the constructs personality, critical life events, and social support on psychogenic impairment was specified in two path models. In both models psychodynamic personality variables had the highest impact on the criterium. Psychodynamically consistent, the ability to establish mature object relations and the maturity of ego functions was inversely related to the degree of psychogenic impairment, whereas an immature organisation of defense mechanisms exerted an aggravating influence on the severity of impairment. The present path analyses altogether point to a possible central etiological impact of personality and/or psychodynamic variables on the severity of psychogenic impairment.

Adaptation, Psychological↗
PubMed1993

[Prognostic indicators of psychogenic diseases in adulthood based on childhood variables].

Using the data of the Mannheim Cohort Projekt (Schepank, 1987, 1990), the authors investigate possible correlations between psychic symptoms in childhood, risk and protective factors with regard to psychogenic disorders in adulthood. For this, the number of symptoms and the "Impairment-Score" as the degree of psychogenic complaints were related to each other by determining Spearmen's rank correlation coefficient. Additionally, the predictive power of these three variables were investigated by means of discriminance analysis. It could be shown, that the severity of psychogenic illness in adulthood increases with the number of childhood symptoms. There was no evidence for the hypothesis of an increasing predictive power for the assembled variables (number of symptoms, risk factors, and protective factors) in comparison with the single variables. The results found are, however, comparable to the data of two prospective longitudinal studies.

Adaptation, Psychological↗
PubMed1993

[Incidence and follow-up characteristics of neurologically relevant psychogenic symptoms].

The author reports on the prevalence and stability of the course of neurologically relevant psychogenic symptoms as well as their dependence on age and sex. Altogether 240 probands from the Mannheim Cohort Study on the epidemiology of psychogenic disorders were examined for psychogenic impairment over a 10-year period during three investigation periods. On the whole, seven neurologically relevant groups of symptoms (headache, lumbar and cervical vertebral complaints, non-systematic vertigo, functional hyperkinesia, functional paresis, sleep disturbances, concentration disturbances) differ clearly in frequency, characteristics of the course and clinical relevance.

Adult↗
PubMed1993

[Why "no" to psychotherapy? Cognitive stereotypes of psychosomatic patients of a population sample in correlation with refusal of offered psychotherapy].

Practical and organizational reasons, e.g. problems of timing, and strain factors in private or professional life are cited predominantly when probands spontaneously utter their motives for the non-acceptance of an offer of psychotherapy. In the second place, a lack of insight into the necessity of this kind of treatment is indicated as motive for the rejection of a therapy offer. An exploration of the probands leads to a change in the frequently distribution of the motives uttered to refuse psychotherapeutic treatment. Basically, the differentiation of the answers increases (indication of more than one category of motives). A negative attitude to or fear of psychotherapy was indicated considerably more often, especially by women. Those--mostly male--probands, who had pointed out that a lack of insight into the necessity of psychotherapeutic treatment was the decisive factor for their non-acceptance of the therapy offer, adhered most consistently to their argumentation also after exploration. The statistical analysis of possible determinants for the different styles in which probands state the motives for their rejection revealed significant sex differences. These findings suggest that the uptake of psychotherapeutic treatment is also guided by sex role sterotypes.

Adult↗
PubMed1993

Secondary hyperparathyroidism and acute tubular necrosis following renal transplantation.

In the present study we investigated the relationship between secondary hyperparathyroidism in renal graft recipients and post-transplantation acute tubular necrosis (ATN). Patients were divided into two groups according to graft function: group A consisted of 28 patients who had an uneventful postoperative period and did not require haemodialysis. Group B comprised 26 patients with primary non-function of the graft due to biopsy-proven ATN who required continued haemodialysis for the first postoperative week or longer (mean 14.2 +/- 8.7 days). Both groups had comparable donor characteristics, HLA-matching and ischaemia times. All patients were given cyclosporin and low-dose prednisolone for immunosuppression. Pretransplant levels of intact PTH were significantly greater in group B than in group A (203.5 +/- 193.1 pg/ml versus 81.7 +/- 45.2 pg/ml, P < 0.01). Group B patients had more transplant biopsies (50 versus 7) and a longer hospitalization time (33.4 +/- 10.9 days versus 21.9 +/- 11.9 days, P < 0.01), although serum creatinine on the day of discharge was higher in group B (1.77 +/- 0.51 mg/dl versus 1.5 +/- 0.45 mg/dl, P < 0.05). We conclude that patients with secondary hyperparathyroidism as assessed by measuring circulating levels of intact PTH have an increased incidence of ATN.

Adult↗
PubMed1993

[Psychometric assessment of defense mechanisms: correlation between questionnaire and expert rating. Initial study of validity].

Within the limits of an epidemiological longitudinal field survey on prevalence and course of psychogenic disorders a high-risk-population suffering from medical psychogenic impairment was investigated. The study was conducted in order to verify an etiological multi-level-model of psychogenic disorders in relation to the socialempiric variables "critical life events" and "social support" as well as the depth psychological oriented construct "personality". Besides other instruments a self rating scale based on Vallant's hierarchical model of defense, i.e. the german adaptation of the DSQ (Defense Style Questionnaire) of Bond and coworkers, was used for the accurate measurement of relevant personality parameters. Although defense processes predominantly work unconscious, manifestations of defense mechanisms could be measured indirectly by means of the rating scale. Its essential dimensions separated clinical patients from a group of healthy controls. Furthermore an immature organisation of defense was found to be related to psychogenic impairment. Concerning self- and expert-rating a significant correlation between "immature defense" and the defense mechanisms "schizoid phantasy", "projection" and "acting out" was proved.

Adult↗
PubMed1992

The bilayer floating capsule: a stomach-directed drug delivery system for misoprostol.

A bilayer floating dosage unit is proposed to achieve local delivery of misoprostol, a prostaglandin E1 analogue, at the gastric mucosa level. The system is a capsule consisting of a floating layer maintaining the dosage unit buoyant upon the gastric content and a drug layer formulated to act as a sustained-delivery system. The differential design of the two layers allows the optimization of both floating capability and drug release profile. The layers are both composed of a hydrophilic matrix based upon hydroxypropylmethyl cellulose (HPMC). Parameters influencing the release profiles are described. The use of a large capsule increases the gastric residence time (GRT), as it impedes passage through the pylorus opening. gamma-Scintigraphic studies were performed to visualize cohesion of the two layers in vivo and to determine GRT as a function of meal regimen. The average GRTs were 199 +/- 69 min after a single meal (breakfast) and 618 +/- 208 min after a succession of meals.

Adult↗
PubMed1992

Evidence that sensitivity to cyclosporine is influenced by the HLA-DR phenotype of kidney graft recipients.

Clinical as well as experimental studies have shown a great interindividual variability in the immunosuppressive efficacy of CsA. Evaluating previous in vitro findings of a correlation between sensitivity of alloresponsiveness to CsA and the HLA-DR phenotype CsA levels were compared in kidney transplant recipients with and without rejections during the early posttransplant period and tested for a possible relationship to the HLA-DR phenotype of the recipient. In patients treated with CsA and prednisolone only, rejection frequency was significantly higher in HLA-DRw6 positive than in DRw6 negative graft recipients (77% vs. 53%, P = 0.045). In the DRw6 positive group incidence of rejection was independent of CsA blood levels, whereas in DRw6 negative patients frequency of rejection episodes decreased as a function of increasing CsA levels. Therefore the relative risk in developing graft rejection continuously increased in HLA-DRw6 positive patients. In HLA-DR2 positive graft recipients, however, a decrease in the relative risk could be observed with increasing CsA levels. Within patients with bioptically verified rejection episodes HLA-DR2 positive recipients had significantly lower CsA levels than DR2 negative patients (P = 0.01). In other HLA-DR phenotypes no association with CsA blood levels could be assessed. Also no statistically significant difference could be found in nonrejecting patients. These clinical findings demonstrate an association of sensitivity to immunosuppressive treatment and the HLA-DR phenotype of the graft recipient. Our results would indicate a very low CsA sensitivity of HLA-DRw6 positive graft recipients and thus might offer an explanation for previous findings about an increase in the incidence of rejection reported on those patients.

Adult↗
PubMed1992

Effects of sympathetic stimulation on use dependence of lidocaine, mexiletine, and quinidine in an intact canine model.

The use- or rate-dependent effects of a continuous infusion of lidocaine (n = 6, serum level 3.1 +/- 0.34 micrograms/mL), mexiletine (n = 8, serum level 7.08 +/- 0.90 micrograms/mL), and quinidine (n = 6, serum level 6.8 +/- 1.22 micrograms/mL) were studied in an open chest canine preparation. A use-dependent effect on conduction was assessed by measuring the change in the His to surface ventricular activation (HV) time at differing atrial paced rates during drug infusion. Global sympathetic activation was achieved by nondecentralized left stellate ganglion stimulation (4-10 Hz, 6-12 V, 2 ms) and use dependence at the same cycle lengths was compared. Repolarization times were measured from epicardial monophasic action potentials recorded from the anterior left ventricle throughout the study. There was no significant change in the HV time during control studies with or without left stellate stimulation. Use-dependent slowing of conduction was seen in all studies during drug infusion. This was evident at cycle lengths of 300-190 ms for quinidine and at cycle lengths less than 250 ms for lidocaine and mexiletine. Stellate stimulation attenuated use dependence in all studies. This effect was significant from cycle lengths of 300-190 ms for lidocaine and quinidine and at cycle lengths shorter than 230 ms for mexiletine (p less than 0.05). Stellate stimulation significantly reduced use-dependent prolongation of the HV interval by an average of 60%. During stellate stimulation there was a nonsignificant trend towards cycle length independent shortening of action potential duration both at baseline and in the presence of drugs.(ABSTRACT TRUNCATED AT 250 WORDS)

Action Potentials↗
PubMed1992

Treatment of hyperlipidemic kidney graft recipients with lovastatin: effect on LDL-cholesterol and lipoprotein (a).

An increased incidence of hyperlipidemia places kidney graft recipients at increased risk for cardiovascular disease and may contribute to a decline in graft function. A study was undertaken to evaluate the safety and efficacy of lovastatin in these patients. Twelve kidney graft recipients with stable graft function and a cholesterol (chol) level over 250 mg/dl (6.46 mmol/l) were included. The lipid-lowering treatment consisted of 20 mg lovastatin daily, and all patients received immunosuppression with ciclosporin (CS) and prednisolone. Total chol decreased by 27% (300 +/- 56 to 219 +/- 28 mg/dl; 7.76 +/- 1.45 to 5.66 +/- 0.72 mmol/l; p < 0.01), LDL-chol by 35% (220 +/- 38 to 143 +/- 17 mg/dl; 5.69 +/- 0.98 to 3.70 +/- 0.44 mmol/l; p < 0.01) and triglycerides by 33% (207 +/- 127 to 138 +/- 56 mg/dl; 2.36 +/- 1.44 to 1.57 +/- 0.64 mmol/l; p < 0.05). HDL-chol increased by 10% (57 +/- 11 to 63 +/- 13 mg/dl; 1.47 +/- 0.28 to 1.63 +/- 0.34 mmol/l; NS). The ratio of total chol/HDL-chol, a generally accepted risk predictor of atherosclerosis, fell from 5.4 +/- 1.3 to 3.3 +/- 1.2, p < 0.01. Lipoprotein (a) [lp(a)], an independent risk predictor for atherosclerosis, was also evaluated at baseline and after 6 months of lovastatin treatment and showed a decrease of 39% (32.9 +/- 27.6 to 19.9 +/- 22.9 mg/dl; 0.85 +/- 0.71 to 0.51 +/- 0.59 mmol/l; p < 0.05). No adverse side effects were seen at this dosage, and hepatic and renal parameters remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Psychogenesis of the course of Sudeck's disease--a case report].

Several authors have already pointed out the significance of personality, subjectively stressful life events and relevant conflicts for the course of reflex sympathetic dystrophy. Psychodynamic hypotheses are demonstrated by two patients who had psychotherapeutic treatment and were observed over a longer stretch of time. A therapeutic concept which is enriched by this knowledge may obtain the patients' better compliance with orthopaedists, surgeons and physiotherapists and may influence duration of illness and treatment results favorably.

Adaptation, Psychological↗