[Social Differences in Physical Activity among Adolescents in Germany: Analyses Based on Information Concerning the Metabolic Equivalent of Task (MET)]. / Soziale Unterschiede in der körperlich-sportlichen Aktivität bei Jugendlichen: Analyse der MoMo-Daten mithilfe der metabolischen Äquivalente (MET).

Introduction: Energy consumption, i. e., the metabolic equivalent of task (MET), provides a precise assessment of physical activity (PA). Studies on social inequalities of PA have hardly used this possibility, however. Methods: The analyses are based on the 'Motorik-Modul (MoMo) of the KiGGS study (German Health Interview and Examination Survey for Children and Adolescents) conducted between 2003 and 2006 (n=1 757; age group 11-17 years). PA has been assessed in 3 settings (sport club in school, other sport club, leisure time). 3 dependent variables were distinguished by combining the following criteria: at least 21 MET-hours per week, intensity between 3 and 6 METs, at least 7 hours a week. The main independent variables are: type of school and socioeconomic status (SES) of the parents. 'Two part models' have been used to assess social difference in PA among those who are physically active. Results: PA is much more common in the higher SES groups. Looking at the MET-hours, though, there are just little differences among those who are physically active (regressions coefficient for low vs. high SES: 1.15; 95% conf. interv. 0.99-1.33). Conclusion: Social differences can be seen mainly for the proportion of adolescents being physically active, not for the extent of PA among those who are physically active. Therefore, the central request should be to increase the proportion of adolescents performing any PA in the low SES group.

[Endoprosthetic tumor replacement : Reconstruction of the extensor mechanism and complications]. / Tumorendoprothetik : Rekonstruktion des Streckapparates und Komplikationen.

BACKGROUND: The reconstruction of the extensor mechanism around the knee is an essential part of tumorresection and tumor arthroplasty in orthopaedic oncology for functional rehabilitation of quality of life and daily activities. OBJECTIVES: Operative procedures, treatment options and management of complications with reconstruction of the extensor mechanism after tumor resection around the knee depend on the type of arthroplasty. MATERIALS AND METHODS: Description of the different treatment option for extensor deficiency divided into infra- and suprapatellar modalities. RESULTS: The operative procedure is always an individual decision depending on the size of the tumor and its localisation. The extensor mechanism is reconstructed with autogenic, allogenic or synthetic material in combination with tumor arthroplasty. CONCLUSIONS: Extensor reconstruction (supra-/infrapatellar) is an essential part of tumor resection and tumor arthroplasty around the knee. Often, low functional results and high levels of complications (arthrofibrosis, rerupture extensor mechanism, periprosthetic joint infection) are seen in these highly demanding cases in orthopaedic oncology.

Species and tissue specificity of mammalian GTP cyclohydrolase I messenger RNA.

Northern blot analysis of rat RNA from cell lines and isolated organs with a specific rat cDNA probe detected two GTP cyclohydrolase I mRNA species of approx. 1.4 and 3.6 kb. The ratio between these two species varies between 0.6 and 2.4 in different rat organs. Using primers derived from highly conserved regions in the rat and Escherichia coli cDNA sequences a human GTP cyclohydrolase I probe was obtained by means of reverse transcription and PCR (polymerase chain reaction). The human PCR product consisting of 555 bp was cloned and sequenced. It shows a 92% identity with the published sequence of the rat gene. The analysis of various human cell lines with this specific probe shows only one species of GTP cyclohydrolase I mRNA with an approximate size of 3.6 kb.

Heavy riboflavin synthase from Bacillus subtilis. Crystal structure analysis of the icosahedral beta 60 capsid at 3.3 A resolution.

Geometric features as well as possible functional properties of the substrate binding sites at the pentamer interfaces are described. Ligand binding at the pentamer interface regions increases the stability of the beta 60 capsid considerably and influences the reassembly of isolated beta-subunits.

Oxaloacetate transport into plant mitochondria

The properties of oxaloacetate (OA) transport into mitochondria from potato (Solanum tuberosum) tuber and pea (Pisum sativum) leaves were studied by measuring the uptake of 14C-labeled OA into liposomes with incorporated mitochondrial membrane proteins preloaded with various dicarboxylates or citrate. OA was found to be transported in an obligatory counterexchange with malate, 2-oxoglutarate, succinate, citrate, or aspartate. Phtalonate inhibited all of these countertransports. OA-malate countertransport was inhibited by 4, 4'-dithiocyanostilbene-2,2'-disulfonate and pyridoxal phosphate, and also by p-chloromercuribenzene sulfonate and mersalyl, indicating that a lysine and a cysteine residue of the translocator protein are involved in the transport. From these and other inhibition studies, we concluded that plant mitochondria contain an OA translocator that differs from all other known mitochondrial translocators. Major functions of this translocator are the export of reducing equivalents from the mitochondria via the malate-OA shuttle and the export of citrate via the citrate-OA shuttle. In the cytosol, citrate can then be converted either into 2-oxoglutarate for use as a carbon skeleton for nitrate assimilation or into acetyl-coenzyme A for use as a precursor for fatty acid elongation or isoprenoid biosynthesis.

Prednisolone therapy of experimental allergic neuritis in Lewis rats does not induce relapsing or chronic disease.

The effects of therapeutic prednisolone treatment on experimental allergic neuritis (EAN) in Lewis rats were evaluated in a controlled clinical and electrophysiological study. Since steroid therapy has been suspected to cause relapsing or chronic disease, monitoring was extended over 200 days. Short-term steroid treatment (5 days of 15 mg/kg prednisolone, n = 8) with sudden steroid withdrawal was compared with long-term application (30 days, beginning at 7.5 mg/kg) in descending dosage (n = 8). The experiment included saline-injected controls (n = 8) and controls for stress possibly exerted by the handling of the animals. Treatment was begun at the onset of clinical signs. The clinical and electrophysiological data indicated that deterioration, recovery and mild (insignificant) relapse (after day 30 and day 108) occurred in all groups at the same time. Both steroid application schemes significantly (p less than 0.03) attenuated the severity and shortened the duration of EAN. Relapse was not aggravated after steroid treatment. The clinical course and electrophysiological findings were unaltered by the experimental procedures and by mild experimental stress.

Demyelination of sciatic nerve in acute experimental allergic neuritis of the rat. A gel electrophoresis investigation.

Acute experimental allergic neuritis (EAN) of Lewis rats was monitored by clinical and electrophysiological tests for 60 days. Sciatic nerve myelin proteins were analyzed by quantitative microgel electrophoresis and electroimmunoblotting at different clinical stages of the disease. The clinical severity of EAN and the demyelination as measured by electrophysiological tests and myelin protein concentrations in sciatic nerve did not correspond during the course of the disease. Demyelination reached its peak after partial clinical recovery and was still present on day 60. The major peripheral nervous system (PNS) myelin proteins P0, P1 and P2 decreased at different rates during the course of the disease, indicating possible differences in their proteolytic degradation. Treatment with Freund's complete adjuvant (CFA) alone resulted in alterations of membrane and myelin protein patterns challenging the widely held belief that pure CFA is inert with regard to demyelination.

The use of protease inhibitors in experimental allergic neuritis.

In experimental allergic neuritis (EAN) break-down of myelin is attributed to macrophages, which among other factors contain and secrete proteases. In vitro studies have shown that cathepsin D, an acidic aspartyl endopeptidase, and plasmin can degrade myelin proteins. In order to elucidate a potential therapeutic effect of protease inhibitors we treated Lewis rats, immunized with bovine peripheral nervous system myelin, with epsilon-amino-caproic acid (EACA) or pepstatin. EACA or pepstatin was administered twice daily by intraperitoneal injection beginning on day 6 postimmunization or from the onset of disease (on day 12) through day 24. Compared to saline-treated controls, animals treated with either of the inhibitors showed delayed development of clinical signs and electrophysiological abnormalities. Maximal severity and the further course of disease, however, were not different in control and treated groups. Immunohistological evaluation of sciatic nerve specimens on day 24 postimmunization showed equal numbers of cells positive for ED1 (macrophages) and cathepsin D in all animal groups. There was also no difference in the spontaneous proteolytic activity of the sciatic nerve homogenates at pH 2.8, 5.0, and 7.4. Incubation of the homogenates with pepstatin, however, significantly reduced proteolytic activity at pH 2.8 and 5.0, while EACA had no effect at any pH tested. These results imply that treatment to limit the infiltration of cathepsin D-positive cells or to reduce the induction or activity of cathepsin D may provide a therapeutic avenue for treating inflammatory demyelination of the peripheral nervous system.

Regulation of the amino acid availability in the developing brain. No physiological significance of amino acid competition in experimental hyperphenylalaninemia.

Chronic experimental hyperphenylalaninemia in suckling rats causes a depletion of amino acids in the blood and in the brain, and an accumulation of amino acids in the peripheral tissues. The amino acid depletion in the blood is greater than that in the brain. The amino acid accumulating potency of all body tissues is increased by the excess of phenylalanine, most pronounced in the gut, least pronounced in the brain. All body tissues compete for the amino acids circulating in the blood. This competition is enhanced in hyperphenylalaninemia. The brain is at a disadvantage in the competition of the various body tissues for the amino acids available from the common pool. Brain tissue is increasingly depleted of amino acids as the accumulation of amino acids in the peripheral tissues is stimulated in hyperphenylalaninemia. The depletion of amino acids in the blood and the simultaneous rise of the free amino acid concentrations in the various developing tissues indicates tissue-specific shifts in the balance between protein synthesis and protein degradation in hyperphenylalaninemia. There is no indication that amino acid competition at the blood-brain barrier contributes importantly to the depletion of amino acids in the brain tissue in hyperphenylalaninemic rats. Instead, brain amino acid pools under in vivo steady-state conditions appear to be primarily regulated by the rate of amino acid utilization by the peripheral tissues.

A pharmacological and behavioural study on beta, beta'-iminodipropionitrile (IDPN)-treated brine shrimp Artemia salina L.

The neurotoxic substance beta, beta-iminodipropionitrile (IDPN), which induces hyperkinesia in some mammals, was found to be neurotoxic to the brine shrimp Artemia salina L. (Crustacea, Anostraca) inducing discoordination of limb-movement and sedation of motility. Up to 9 metabolities of IDPN were detected in Artemia, including beta-alanine, cyanoacetic acid, and beta-aminopropionitrile (BAPN). Brine shrimp, especially nauplius (1 day), may be a useful test animal for the biological assay of IDPN.

Autoantibody reactivity in serum of patients with Alzheimer's disease and other age-related dementias.

Serum antibodies against a series of antigens, including an organ-specific central nervous system (CNS) antigen and the neurotransmitter serotonin, were investigated in 22 patients with Alzheimer's Disease (n=15) and other age-related dementias (n=7) by indirect immunofluorescence assay and enzyme-linked immunosorbent assay. Patients with dementia showed an increase of antibody-positive sera against nuclear antigen, gastric parietal cells, CNS antigen, gangliosides (Gm1), laminin, and keratin. Alzheimer's Disease patients alone exhibited antibodies against CNS antigen. However, the results do not show sufficient specificity and sensitivity for use as a diagnostic indicator.

Antinuclear antibodies in schizophrenia and major depressive disorder - a lasting puzzle.

Sera from patients with major depressive disorder and paranoid schizophrenia were screened for antinuclear antibodies (antigens: ds-DNA, ENA, histone H3) and circulating immune complexes (CIC-Cq1) by ELISA. Controls were healthy blood donors. Only a few of the patients' sera were positive for anti-ds-DNA and anti-ENA antibodies. There was no significant result. In paranoid schizophrenia 20.5% of sera were positive for antibodies against histone H3. In the case of CIC-Cql, 7% of the patients with major depressive disorder and 11 % of those with paranoid schizophrenia were positive. Controls showed positive sera in 39%. This study disagrees with former studies which could demonstrate a series of antinuclear antibodies in mental disorders. In the case of antihistone antibodies, the present results could indicate an autoimmune process in a subgroup of schizophrenic patients.

Intra-aortic balloon counterpulsation as a therapy for shock.

As early as 1967, IABC has been effectively used to support patients in cardiogenic shock. IABC provides the temporary circulatory assistance necessary to maintain coronary perfusion pressure, improve stroke volume and cardiac output, and decrease left ventricular preload and afterload. Until new forward flow devices are perfected and become globally available as mechanical assistance for pump failure, the intra-aortic balloon pump will continue to provide temporary mechanical circulatory assistance to support patients in cardiogenic shock until diagnosis of the underlying cause and definitive therapy can be determined.