Muscle glycogen repletion from endogenous carbon sources during recovery from high intensity exercise in the fasted rat

During recovery from high intensity exercise, substantial and rapid muscle glycogen repletion from endogenous carbon sources is reported in a variety of vertebrate species, the rat being the only reported exception. The major aim of this study was to re-examine the process of glycogen repletion during recovery from high intensity exercise in the rat. In response to 3 min of vigorous swimming, muscle glycogen concentrations decrease markedly from initial levels of 20.2±1.5 and 21.2±0.9 μmol g^-1 to 6.4±1.1 and 7.9±1.4 μmol g^-1 in the tibialis anterior and plantaris muscles respectively. The equivalent of 58% of the glycogen carbons mobilized during exercise by the plantaris and 73% of that mobilized by the tibialis anterior muscle is repleted within 1 h following exercise. Using the hepatectomized rat as experimental model, a secondary aim of the study was to evaluate whether the liver is essential for the repletion of muscle glycogen. Although the absence of significant differences in the magnitude of post-exercise muscle glycogen repletion between sham-operated and hepatectomized rats suggests that the resynthesis of muscle glycogen can take place in the absence of hepatic gluconeogenesis, the present study identifies several limitations in the use of acute hepatectomy. Overall, the present study indicates that, in contrast to published views, the rat resembles other vertebrates in that it can support extensive muscle glycogen repletion from endogenous carbon sources during the recovery phase following high intensity exercise.     

Mitotic and meiotic detection of radiation-induced translocations in mouse stem cell spermatogonia using fluorescencein situ hybridization

The efficiency of two methods of detection of translocations induced in mouse stem cell spermatogonia by X-ray doses of 2, 5 and 7 Gy was compared: classical multivalent analysis at diakinesis-metaphase I of meiosis and observation via fluorescencein situ hybridization analysis of mitotic or meiotic stages. Specific DNA libraries for chromosomes 1, 11 and 13 were used. The results obtained indicate that (a) chromosomes 1, 11 and 13 are more involved in multivalent formation than expected on the basis of DNA content and (b) if the mitotic FISH analysis data are corrected for the observed over-representation, the frequencies of induced translocations are similar to those recorded in the classical multivalent studies, suggesting equal scoring efficiencies in both systems.     

Development and assessment of an objective method of colour change measurement for acrylic denture base resins

SUMMARY Current standard specifications for the laboratory evaluation of denture base materials require subjective assessment of colour stability. This study evaluates a new objective measurement technique for translucent denture base materials, by comparing quantitative data with the results obtained from a standard subjective method. Preliminary work on three representative commercial acrylic materials resulted in the selection of a white background for the quantification of colour change of these translucent materials. One half of each sample was exposed to artificial sunlight for 24 h.
The colour of both exposed and unexposed resin was measured on the CIE L*a*b* scale using a photoelectric colorimeter. Significant changes in the b* and E* values (P < 0.001) were observed following light exposure. Objective data for a wide range of commercial materials were compared with the results of a subjective evaluation and it was shown that a change in b* of 1.5 units was discernable subjectively by eye for 100% of the cases. It is suggested that this method and limit value could form the basis of a new objective colour change specification for polymeric dental materials.     

A clinical and radiological two‐year follow‐up study of maxillary overdentures on osseointegrated implants

In order to satisfy the need to restore the aesthetics, phonetics and comfort and to facilitate optimal hygiene procedures, 20 edentulous patients were treated with a new concept of overdenture therapy on implants ad modum Brånemark. After 24±3.5 months the patients were re‐examined. They were asked to answer a questionnaire and use a Visual Analogue Scale (VAS) to give their opinion on the prosthetic treatment. The results indicate that an implant‐retained overdenture in the maxilla with this design can satisfy the patients needs in aesthetics, phonetics and comfort and can 1 facilitate oral hygiene measures.     

Anomalies of the position of the spleen in the child Case report and review of the literature from 1896 to 1990

We report on the case of a 6-year-old girl admitted as an emergency with an acute abdomen with the diagnosis of peritonitis; clinical examination under anesthesia revealed the presence of an abdomino-pelvic mass. Laparotomy confirmed the diagnosis of torsion of an ectopic spleen. Splenectomy was required because the spleen was gangrenous. A review of the literature from 1896 to 1990 revealed reports of 74 cases. Epidemiology, etiology, pathophysiology, the diagnostic and therapeutic problems are discussed.

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Ektopische Milz beim Kind: Fallbericht und Literaturübersicht 1896–1990

Zusammenfassung Anhand eines Fallberichtes und einer Literaturübersicht über 74 Fälle werden Epidemiologie, Ätiologie, Pathophysiologie, Diagnostik und Therapie der im Kindesalter sehr seltenen ektopen Milz besprochen. Die klinischen Zeichen reichen von unspezifischen abdominellen Beschwerden bis hin zum Vollbild eines akuten Abdomen (50%). Die praeoperative Diagnostik richtet sich nach Klinik, Abdomenleeraufnahme und Sonographie, evtl. Computertomographie. Aufgrund der hohen Torsionsraten besteht generell eine Operationsindikation, wobei die Entscheidung über Splenopexie oder Splenektomie sich an dem Lokalbefund orientieren sollte. Zur Splenopexie wurden mehrere Techniken mit gleich guten Resultaten angegeben.

     

Reduced alcohol use in pregnancy and changed attitudes in the population

The objectives of this study were to investigate (1) changes in consumption of alcohol among pregnant women over a period of 5 years (1984/85–1990), (2) changes of attitudes towards drinking during pregnancy in the general population over the same period of time, and (3) possible connections between (1) and (2). The investigation was designed as a cross-sectional study. Our subjects were two representative samples of pregnant women in Oslo, n = 577 and 425, and two representative samples of the Norwegian population, n = 1004 and 1204. The main outcome measures were a self-completed questionnaire for the pregnant women and a personal interview for the general population sample. There was a significant reduction (50% decrease) in alcohol consumption among the second cohort of pregnant women compared with the first. Furthermore, we found an increase during the 5-year period in the number of persons with a restrictive attitude towards alcohol use during pregnancy. There seems to be a connection between these two phenomena, but with our present state of knowledge it is hard to say anything about the causal relationship between them.     

Tumor induction by ras and myc oncogenes in fetal and neonatal brain: modulating effects of developmental stage and retroviral dose

Introduction into fetal rat brain cells of a replication-defective retroviral vector harboring v-Ha-ras and v-gag-myc rapidly causes the induction of highly malignant undifferentiated neuroectodermal tumors following transplantation into the brains of syngeneic hosts [Wiestler, et al. (1992) Cancer Res. 52: 3760–3767]. In the present study, we have investigated the modulating effect of the developmental stage of neural target cells and of the dose of the retroviral vector used in the grafting experiments. Exposure of fetal cells from embryonic day (E)12 or E14 produced a 100% incidence of malignant neuroectodermal tumors which led to the death of recipient animals after a median latency period of 32 days. A 100-fold reduction of the virus dose from 2.062×10⁶ to 2.062×10⁴ focus-forming units/ml resulted in a lower tumor incidence of 25%. Of six neural grafts exposed to v-Ha-ras and v-myc at E16, only one showed evidence of tumorigenesis (low-grade astrocytoma and hemangioma). All other transplants were morphologically normal for observation periods of 26 weeks, indicating a marked loss of transforming activity of ras and myc in more advanced stages of brain development. In retrovirus-exposed donor cells which caused the development of neural tumors in recipient rats, malignant transformation was also evident during culture in vitro, usually after 9–12 days. Oncogene complementation was also studied in the newborn rat brain. After microinjection of the retroviral vector into the brain at postnatal day (P)0, P1 and P3, 5 out of 20 animals (25%) developed a total of seven brain tumors. Histopathologically, three of these neoplasms were malignant neuroectodermal tumors which, in contrast to those induced in fetal brain transplants showed evidence of focal glial and/or neuronal differentiation. In addition, we observed one oligodendroglioma, two hemangiomas and a malignant hemangioendothelioma. These data indicate that neural precursor cells and endothelia of the rat brain represent the major target cells for the complementary action of ras and myc and that the use of target cells from later developmental stages (E16 and postnatal) leads to the induction of both primitive and more differentiated neoplasms.These studies were supported by the Fonds zur Förderung der wissenschaftlichen Forschung in Österreich (Erwin Schrödinger fellowship, JO501-MED), by the Swiss National Science Foundation and by the Cancer League of the Kanton of Zürich