Aluminiumoxidkeramik in der rekonstruktiven Nasenchirurgie. Histologische Untersuchungen am Kaninchen

Summary In cases where a reconstruction of defects in the larynx, oral cavity, the pharynx or in the ear region has been performed using skin flaps, a temporary fistula is formed at the point of entry.This fistula can be closed later after the flap has taken and the flap pedicle dissected.We would like to demonstrate with some examples that with the use of deepithelisation it is possible to achieve a primary wound closure. This way no temporary fistula results and additional surgery is avoided in many cases.Furthermore flap deepithelisation offers a way to bring good vascularised tissue under the skin and cover subcutaneous defects, for example those after radiotherapy.

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Die Veröffentlichung des Manuskripts soll in Laryngol Rhinol Otol (Stuttg) erfolgen     

Effects of partial hepatectomy on organ-specific toxic response to 1,2-dibromo-3-chloropropane (DBCP)

The organ-specific toxic potency of subcutaneously administered 1,2-dibromo-3-chloropropane (DBCP) was compared in partially hepatectomized and sham-operated rats over a dose range of 20--80 mg kg-1 to assess the roles of hepatic and extrahepatic metabolism in protection against acute renal and gonadal injury. Relative kidney weight and the severity of DBCP-induced renal proximal tubular cell necrosis were increased in rats subjected to a partial (70%) surgical hepatectomy 48 h prior to treatment with DBCP at 80 mg kg-1. Relative liver weight was reduced by DBCP in the hepatectomized, but not in the sham-operated rats. The severity of DBCP-induced (80 mg kg-1) hepatocellular centrilobular necrosis was greater in hepatectomized than in sham rats. DBCP reduced the relative weights of the testis and epididymis in a progressive manner and produced dose-dependent seminiferous tubular atrophy within 12 days of treatment. The morphologically apparent lesions of the testis and epididymis were enhanced by hepatectomy. The concentration of non-protein sulfhydryl groups (NPS) in rat liver was increased by partial hepatectomy. Because of the resulting decrease in liver size, however, the total amount of hepatic NPS per kg body weight 48 h post-surgery was lower than in sham rats. The surgery had no effect on renal, testicular or epididymal NPS concentrations of organ weights. Partial hepatectomy greatly increased pentobarbital and ethanol sleeping times, while sleep induction time for pentobarbital was decreased.(ABSTRACT TRUNCATED AT 250 WORDS)     

Catabolic effects and the influence on hormonal variables under treatment with gynodian-depot® or dehydroepiandrosterone (DHEA) oenanthate

53 patients from a mainly climacteric population were treated monthly with 200 mg dehydro-epiandrosterone (DHEA) oenanthate or with 1 ampoule Gynodian-Depot®. Pronounced adiposity was present in 15 of these cases. Hormonal variables were determined before the treatment and during the depot effect of the preparations in order to study the principle which supports the oestrogenic influence and any weight-reducing influence under administration of DHEA. The elimination of lowpolar oestrogens increased considerably in 4 out of 13 post-menopausal cases treated with DHEA. This effect is probably indirect and presupposes intact ovaries. The incorporation of exogenous DHEA into the excretion of 17-ketosteroids and of 17-ketogenic steroids, such as those of androsterone + aethiocholanolone, depends on the size of the initial pool inasmuch as it is higher in small initial pools than in saturated pools - the size of the pool being age-dependent.

An average weight loss of >1 kg/mth was observed under DHEA treatment in 7 out 15 adipose cases. In comparison to the other 8 adipose cases, these 7 were younger and therefore also displayed higher values for 17-ketosteroids and their individual fractions. These circumstances appeared to explain why the administration of DHEA resulted in higher levels of free plasma DHEA which, in contrast to the cases without loss of weight, also resulted in an increase of renal DHEA-sulphate clearance. It was concluded from the findings that this is the explanation for the catabolic effect of exogenous DHEA.

Post-menopausally increased FSH and LH fractions were markedly suppressed in about half of the determinations after Gynodian-Depot administration, the findings indicating that DHEA is probably involved in suppression of the LH fraction.     

Motivated behavior and the estrous cycle in rats

(1) The estrous cycle in the rat may be used to study recurrent changes in motor behaviors and motivation which are strongly related to cyclic hormonal and CNS changes. (2) The peak in motivated behaviors occurs during a sharply defined period on the night between proestrus and estrus and is evident in facilitated wheel-running, lordosis, and intracranial self-stimulation. (3) Behaviors without a clearly motivated character do not show an estrous cyclicity. (4) The estrous cyclic variation in intracranial self-stimulation was observed at a specific locus — the pars campacta of the substantia nigra. (5) A neurochemical link between sexually motivated behavior, wheel running and intracranial self-stimulation is suggested. This link is in part dopaminergic but is probably also activated by many other systems.     

Les onze propositions issues des 3es États généraux des malades du cancer et de leurs proches de la Ligue contre le cancer

Sans résumé     

The brain/mind complex. An epistemological approach.

It is stressed that the brain/mind complex constitutes a monolithic system that functions with emergent properties at several levels of hierarchical organization. These hierarchical levels are non-reducible to one another; they are at least three (neuronal, functional, and semantic), and they function within an interactional plan. From the epistemological view-point, the brain/mind complex uses logical and non-logical mechanisms to deal with day-to-day problems. Logic is necessary for the thinking process, but it is not sufficient. Emphasis is given to non-logical mechanisms; fuzzy logic and heuristics, which allow the mind to develop strategies to find solutions, are analysed.     

The precision of positron emission tomography: theory and measurement

The limits of quantitation with positron emission tomography (PET) are examined with respect to the noise propagation resulting from radioactive decay and other sources of random error. Theoretical methods for evaluating the statistical error have been devised but seldom applied to experimental data obtained on human subjects. This paper extends the analysis in several ways: (1) A Monte Carlo method is described for tracking the propagation of statistical error through the analysis of in vivo measurements; (2) Experimental data, obtained in phantoms, validating the Monte Carlo method and other methods are presented; (3) A difference in activation paradigm, performed on regional CBF (rCBF) data from five human subjects, was analyzed on 1.6-cm diameter regions of interest to determine the mean fractional statistical error in PET tissue concentration and in rCBF before and after stereotactic transformation; and (4) A linear statistical model and calculations of the various statistical errors were used to estimate the magnitude of the subject-specific fluctuations under various conditions. In this specific example, the root mean squared (RMS) noise in flow measurements was about three times higher than the RMS noise in the concentration measurements. In addition, the total random error was almost equally partitioned between statistical error and random fluctuations due to all other sources.     

Measuring behaviour: The tools and the strategies

Animal behaviour can be viewed as a stream of elements, which, once accurately described, can be counted and timed. Data acquisition techniques and tools are reviewed, and some strategies for collection and analysis of data using PC computers are suggested. Automated instruments are not satisfactory for the study of complex behaviour and as such systemic observation remains irreplaceable. IBM PC-type computers, with a wide range of analytical software (e.g., spreadsheets, statistical packages, technical graphics), are practical for data acquisition. Several systems which can satisfy different applications are reviewed. Some systems can communicate with a videorecorder, a facility which remarkably increases the accuracy of measurement; this is essential for meaningful analyses of the internal structure of behavioural streams (sequences, time patterns) or communication processes. The power of new tools enables behavioural measurement with the necessary complexity to allow a whole new set of questions to be addressed. However, it also increases demands for meaningful content and analysis of data.     

Humoral and cellular immunity following severe head injury: review and current investigations.

Infection is a common and serious complication of severe head injury. Immunocompetence in 25 severely head injured patients was investigated by measuring: (1) delayed-type hypersensitivity (DTH) skin test responses to common antigens; (2) phytohaemagglutinin (PHA) stimulated peripheral blood lymphocyte (PBL): blastogenesis, phenotype expression, and lymphokine production; (3) lymphokine-activated killer (LAK) cytotoxicity, antibody dependent cellular cytotoxicity (ADCC) and natural killer (NK) cytotoxicity; and (4) immunoglobulin and complement levels. The incidence of anergy to DTH skin testing was 100%. There was a decrease in PHA stimulated: PBL blastogenesis (p = 0.002), T-cell expression (p = 0.018), helper T-cell expression (p less than 0.001), interleukin-2 receptor expression (p less than 0.001), interleukin-2 production (p = 0.035) and gamma-interferon production (p less than 0.001). LAK cytotoxicity was depressed following incubation with IL-2 (p less than 0.001). There was no significant decrease in immunoglobulin levels and all acute phase reactants tested increased. The results of this study indicate that the cellular arm of immune response, including lymphocyte activation and cytokine production, is suppressed following severe head injury. The lack of enhancement in LAK cytotoxicity following incubation of PBLs with interleukin-2 suggests that factors other than decreased interleukin-2 production, such as the inherent lymphocyte dysfunction, other soluble mediators or suppressor cells, may be responsible for the reduction in cellular immunity observed following severe head injury.