Die Erythrokinetik bei Osteomyelofibrose

Zusammenfassung Bei 20 Patienten mit Osteomyelofibrose wurden Erythrocytenbildung und Erythrocytenzerstörung mit Hilfe von Cr⁵¹ und Fe⁵⁹ z. T. nach simultaner Verabreichung dieser Isotope untersucht. Die Erythrocytenlebensdauer war oft verkürzt, jedoch meist nicht hochgradig. Nur bei wenigen Kranken war eine aktive Beteiligung der Milz an der vorzeitigen Zerstörung der Erythrocyten nachweisbar. Das Plasmaeisenturnover war fast stets erhöht, die Eiseninkorporation in die Erythrocyten vermindert. Eine extramedulläre Erythropoese war meist, aber nicht ausnahmslos, durch Oberflächenmessung nachzuweisen. Sie fand überwiegend in der Milz statt, doch war die Leber in zwei Fällen der wichtigste Ort der Erythrocytenbildung. Eine Produktion von Erythrocyten im Knochenmark war bei der Hälfte der entsprechend untersuchten Fälle noch in geringem Maße vorhanden. Die komplexe Korrelation dieser Befunde mit den hämatologischen Daten wurde besprochen und die Indikation zur Splenektomie erörtert.

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Summary Production and destruction of erythrocytes were investigated in 20 patients suffering from myelofibrosis. Cr⁵¹ and Fe⁵⁹ were administered simultaneously. The erythrocyte life span was shortened frequently, but only moderately in most instances. In few patients only the spleen played an active part in the accelerated red cell destruction. The plasma iron turnover was increased in most cases, the incorporation of iron into the erythrocytes was decreased. Extramedullary erythropoiesis was demonstrated by means of surface activity measurements in most but not in all patients. It was localised most frequently in the spleen. In two cases, however, the liver was the most important site of erythrocyte production. Some degree of medullary erythropoiesis was seen in 50 percent of our cases. The correlation between these results and the remaining hematological findings as well as the question of when to remove the spleen are discussed.

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Unter technischer Mitarbeit von FräuleinRenate Roesch, FräuleinMargret Philips und FräuleinIngrid Westmattelmann.

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Die Arbeit wurde durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft.     

Barriers to Dissemination: Exploring the Criticisms of Behavior Therapy for Tics

The review by Cook and Blacher (2007 ) suggests that behavior therapy for tic disorders is indeed efficacious. Given the empirical support for these treatments, researchers should begin to place effort on examining various strategies for treatment dissemination. The current article addresses possible barriers to dissemination, focusing specifically on various concerns that have been raised by many medical and psychological care providers. The validity of these concerns is examined in the context of existing data. In addition, limitations of the current literature and future directions for research are discussed.     

Stoffwechseluntersuchungen bei tiefer Hypothermie unter 20° und langdauerndem artefiziellem Kreislaufstillstand

Ohne Zusammenfassung     

Effect of elevated environmental temperature on the antibody response of mice to Trypanosoma cruzi during the acute phase of infection.

When held at 36 degrees C, Trypanosoma cruzi-infected C3H mice survive an otherwise lethal infection with significantly decreased parasitemia levels and enhanced immune responsiveness. Treatment of T. cruzi-infected mice with the immunosuppressive agent cyclophosphamide indicated that the positive effects of increased environmental temperature were primarily due to enhancement of immunity. A parasite-specific, enzyme-linked immunosorbent assay and immunoblot analysis were used to examine the effect of elevated environmental temperature on the production of anti-T. cruzi antibodies. Both the reactivity and diversity of anti-T. cruzi antibodies were found to be lower in infected mice held at 36 degrees C than in infected mice held at room temperature. However, reactivity and diversity could be enhanced by vaccination with culture forms of the parasite.     

Identification and characterization of fast-sedimenting SV40 nucleoprotein complexes.

Simian virus 40 (SV40) nucleoprotein complexes were extracted from nuclei of infected monkey cells and fractionated on neutral sucrose density gradients. Four forms of SV40 chromatin were distinguished by their labeling kinetics and apparent sedimentation coefficients: Replicating viral DNA in 95 S SV40 chromatin was converted to 75 S chromatin when viral DNA replication was completed. A portion of the 75 S chromatin was rapidly assembled into 200 S nucleoprotein complexes and subsequently into 240 S complexes. The 75 S and the fast-sedimenting complexes were further characterized and compared with mature SV40 virus by equilibrium density centrifugation, plaque assay, and electron microscopy. These experiments suggest that the fast-sedimenting forms may represent virion precursors or a subclass of salt-labile virions, but they contain little or no mature virus.     

Expression and secretion of active mouse TIMP-1 using a baculovirus expression vector

Mouse TIMP-1, one of the tissue inhibitors of metalloproteinases important in regulating turnover of extracellular matrix in both normal and pathological tissues, was previously expressed inE. coli in an inactive, nonglycosylated state that required refolding to become functional. Due to the difficulty of renaturation, an alternative to the prokaryotic expression system was sought. Since we are interested in studying the pharmacodynamics and pharmacokinetics of TIMP locally administered by controlled delivery to mice with experimentally induced arthritis, we also needed an efficient way of producing active TIMP in large quantities. Using the pBlueBacII transfer vector, we generated a recombinant baculovirus that in Sf9 cells could express glycosylated mouse TIMP-1 to about 3 mg of active protein/liter conditioned medium.     

Organ specific apoptosis following polymicrobial intraperitoneal infection

Background Leukocyte apoptosis allows safe removal of potentially harmful cells and facilitates resolution of inflammation. We hypothesized that the number of apoptotic cells changes in a disproportionate fashion in parenchymal organs in response to intra-abdominal infection. Materials and methods The percentage of apoptotic cells in the liver, spleen, lung, and peripheral blood was evaluated following cecal ligation and puncture (CLP) in mice. Tissue myeloperoxidase (MPO) levels were measured as an index of neutrophil extravasation. Results Liver & spleen MPO continually increased, while lung MPO remained low after CLP. In parallel to the increase in MPO, liver & spleen apoptosis continually increased throughout the 9-day follow-up period, whereas lung apoptosis remained unchanged. Conclusions The distribution of apoptotic cells during intraperitoneal infection occurs in an organ specific manner, with significant increases in the spleen and liver. This distribution likely reflected the clearance of apoptotic cells as the inflammatory focus became contained. Supported by the American Association for the Surgery of Trauma, John H. Davis Research Scholarship, and by the Veterans Administration Merit Review Project 0005. Received 7 October 2005; returned for revision 22 November 2005; accepted by G. Wallace 23 December 2005     

A genomewide linkage analysis for prostate cancer susceptibility genes in families from Germany

Prostate cancer is a complex disease with a substantial genetic contribution involved in the disease risk. Several genomewide linkage studies conducted so far have demonstrated a strong heterogeneity of susceptibility. In order to assess candidate regions that are particularly relevant for the German population, we performed a genomewide linkage search on 139 prostate cancer families. A nonparametric method (Zlr scores), using GENEHUNTERPLUS, was applied at 500 markers (panel P1400, deCODE), with an average spacing of 7.25 cM. In the entire family collection, linkage was most evident at 8p22 (Zlr=2.47, P=0.0068), close to the previously identified susceptibility gene MSR1. Further local maxima with Zlr>2 (P<0.025) were observed at 1q, 5q and 15q. In a subgroup of 47 families, which matched the Johns Hopkins criteria of hereditary prostate cancer, suggestive linkage was found on 1p31 (Zlr=3.37, P=0.00038), a previously not described candidate region. The remaining 92 pedigrees, with no strong disease history, revealed a maximum Zlr=3.15 (P=0.00082) at 8q13, possibly indicating a gene with reduced penetrance or recessive inheritance. Our results suggest pronounced locus heterogeneity of prostate cancer susceptibility in Germany. In the present study population, the MSR1 gene could play a significant role. Other conspicuous loci, like 1p31 and 8q13, need further investigation in order to verify their relevance and to identify candidate genes.     

Upregulation of TGF-beta, FOXP3, and CD4+CD25+ regulatory T cells correlates with more rapid parasite growth in human malaria infection

Understanding the regulation of immune responses is central for control of autoimmune and infectious disease. In murine models of autoimmunity and chronic inflammatory disease, potent regulatory T lymphocytes have recently been characterized. Despite an explosion of interest in these cells, their relevance to human disease has been uncertain. In a longitudinal study of malaria sporozoite infection via the natural route, we provide evidence that regulatory T cells have modifying effects on blood-stage infection in vivo in humans. Cells with the characteristics of regulatory T cells are rapidly induced following blood-stage infection and are associated with a burst of TGF-beta production, decreased proinflammatory cytokine production, and decreased antigen-specific immune responses. Both the production of TGF-beta and the presence of CD4+CD25+FOXP3+ regulatory T cells are associated with higher rates of parasite growth in vivo. P. falciparum-mediated induction of regulatory T cells may represent a parasite-specific virulence factor.