Bibliothek

Notizen: CHEKANOV, V., et al.: Transplantation of Autologous Endothelial Cells Induces Angiogenesis. This study examined the feasibility and efficacy of autologous endothelial cell (EC) transplantation using a fibrin matrix in the ischemic myocardium of sheep. Four weeks after placing an ameroid constrictor in the circumflex artery of 12 adult sheep, four animals (EC group) were subjected to EC transplantation. In four others (saline [SAL] group) saline with added inactivated cells was injected and four animals served as controls. Eight weeks after treatment the animals were sacrificed to assess histology and ultrastructure. Eight weeks after injection, ventricular function was markedly improved in the EC transplant group, but had deteriorated in the SAL and control groups. Myocardial blood flow was also increased in the EC group. Histology and electron microscopy revealed extensive neovascularization after EC transplantation and improved myocardial appearance. Heterotopic transplantation of EC within a fibrin matrix enhances neovascularization, increases myocardial blood flow, and improves left ventricular function. (PACE 2003; 26[Pt. II]:496–499)

Notizen: Three experiments were conducted that were designed to evaluate our ability to predict essential amino acid (EAA) needs of hybrid striped bass using the quantified lysine requirement and whole-body amino acid concentrations. In the first experiment, six diets containing various amino acid profiles were fed to triplicate groups of fish initially weighing 7.7 g per fish. At the end of the 8-week experiment, no significant differences were detected in growth rates or feed efficiencies (FE) between fish fed a practical diet containing 510 g kg−1 herring fish meal (FM) and fish fed a purified diet containing the amino acid profile of herring fish meal (CAA-FM). Growth responses of fish fed purified diets containing 100 (HSB), 110 (HSB110), 120 (HSB120) or 140 g 100 g−1 (HSB140) of the amino acid profile of hybrid striped bass whole-bodies were significantly lower than those of fish fed diet FM. In the second experiment, triplicate groups of fish (5.6 g per fish) were fed diets containing various energy : protein (E : P) ratios (34.8, 41.2, 47.5 and 53.9 kJ g−1 protein) and one of two amino acid profiles (CAA-FM and HSB120) in a 4 × 2 factorial design. Carbohydrate concentration was varied to achieve the desired energy concentrations. At the end of the 8-week experiment, weight gain and FE were significantly higher in fish fed diets formulated to simulate the amino acid profile of herring fish meal (CAA-FM) compared with fish fed diets formulated to contain 120 g 100 g−1 of the amino acid profile of hybrid striped bass whole-bodies (HSB120). Weight gain, FE and survival data indicated the optimum dietary E : P was 41.2 kJ g−1 protein. Dietary treatments in the final experiment included three amino acid profiles and four levels of lipid in a 3 × 4 incomplete factorial design. Dietary amino acid treatments included the amino acid profile of herring fish meal (CAA-FM) or 120 g 100 g−1 of the predicted EAA requirement profile for hybrid striped bass (HSB120). The amino acid profile of the remaining dietary treatment (PRED+) was similar to that of the HSB120 treatment, but contained additional threonine, isoleucine and tryptophan. Diets CAA-FM and HSB120 contained either 90, 130, 170 or 210 g kg−1 lipid, whereas diet PRED+ contained 130 g kg−1 lipid. Dietary treatments were fed for 10 weeks to triplicate groups of fish initially weighing 81.0 g per fish. Weight gain and FE were not significantly affected by dietary amino acid profile. Feed efficiency was significantly reduced in fish fed diets containing 210 g kg−1 lipid compared with fish fed diets containing 90–170 g kg−1 lipid. Intraperitoneal fat (IPF) ratio and hepatosomatic index (HSI) values generally increased as dietary lipid concentrations increased. Total liver lipid concentrations were significantly reduced in fish fed diets containing 210 g kg−1 lipid compared with those of fish fed 90–130 g kg−1 lipid. Results of this study indicate an appropriate dietary amino acid profile can be predicted for hybrid striped bass using the quantified lysine requirement and whole-body amino acid concentrations. Further, the optimum E : P appears to be 40 kJ g−1 protein.

Notizen: Ras is a small monomeric GTP binding protein that transduces signals for growth and differentiation of eukaryotic organisms. Previously, a unique ras gene, designated Ct-ras, was cloned from the alfalfa fungal phytopathogen, Colletotrichum trifolii. Expression of Ct-Ras in mouse fibroblast cells (NIH3T3) demonstrated that Ct-ras is functionally similar to the mammalian ras genes since activating mutations of Ct-ras caused oncogenic phenotypes in nu/nu mice, including tumors. In C. trifolii, activated ‘oncogenic’ Ras (Val2) induced abnormal hyphal proliferation, defects in polarized growth and significantly reduced differentiation such as conidiation and appressorium formation in a nutrient dependent manner. Gene disruption of ct-ras was lethal. To further evaluate the function of Ct-Ras in C. trifolii, three different approaches were used: overexpression of cytosolic Ras by CAAX box deletion; expression of dominant negative Ct-RasT22N; and antisense ct-ras expression. Results showed that suppression of Ct-Ras activity significantly decreases fungal germination frequencies and hyphal growth rates. Taken together, these data suggest involvement of Ct-Ras in regulation of fungal cell growth and differentiation.

Notizen: Abstract: The 32S + 100Mo and 36S + 96Mo fusionlike reactions were studied at incident energy of E lab = 298 MeV and 320 MeV, respectively, with the aim of probing the influence of the entrance channel charge asymmetry on the dipole γ-ray emission. The excitation energy and spin distribution of the compound nucleus created in these reactions were identical, the only difference being associated with the unequal charge asymmetry of the two entrance channels. High-energy γ-rays were detected in an array of 9 seven-pack BaF2 clusters. Coincidence with fusionlike residues detected in four PPAC ensured the selection of central reaction events. By studying the differential γ-ray multiplicity associated with the two reactions it was shown that the dipole strength excited in the compound nucleus increases with the entrance channel charge asymmetry. From the linearized spectra, the increase of the GDR γ-ray intensity was found to be ∼ 25% for the more charge asymmetric system. The results are discussed and compared with those of previous data obtained at different incident energies.