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In this study, electrospun cellulose acetate - poly(ethylene oxide) nanofibrous membrane was found to be unique in immobilizing bacterial cells. Here, removal of methylene blue in aqueous media was achieved by using isolated species of bacteria (Bacillus paramycoides) from industrial wastewater and immobilized on cellulose acetate- poly(ethylene oxide) nanofibers using DMSO as a solvent. The decolorization time was varied from 0 to 72 h, different dye concentrations from 20 to 200 mg/L and bacterial cells count was investigated to achieve the maximum MB removal by bacteria-immobilized CA/PEO nanofibrous membrane. The effective dye decolorization was achieved within 48 h and MB removal % was around 93%. Furthermore, reusability of the bacteria-immobilized CA/PEO nanofibrous membrane was tested. It was found that after the 4th usage, 44% of the dye decolorization capacity still could be achieved. These results are promising and suggest that bacteria-immobilized CA/PEO nanofibrous membrane could be economically feasible and eco-friendly when used in MB removal from industrial wastewater. Combination of both adsorption and biodegradation methods was found to be effective in MB removal from aqueous media.

Ivermectin (IVM) is a chemically modified macrocyclic lactone of Streptomyces avermitilis that acts as a potent neurotoxin against many nematodes and arthropods. Little is known of IVM's effect against either blood-feeding Phlebotomus sand flies, or the infective promastigote stage of Leishmania transmitted by these flies. We injected hamsters subcutaneously with two standard IVM treatments (200 and 400 μg/kg body weight) and allowed cohorts of Leishmania major-infected Phlebotomus papatasi to blood-feed on these animals at various posttreatment time points (4 h, 1, 2, 6, and 10 days). Infected and uninfected sand flies that bit treated and untreated hamsters served as controls. Serum levels of IVM in low- and high-dose-treated hamsters were determined at the five time points. Sand fly mortality following blood feeding was recorded at 24-h intervals and, in relation to IVM treatment, was time and dose dependent. Mortality was most rapid and greatest among infected flies that fed nearest to time of dosing. Mean survival of infected sand flies after feeding on untreated hamsters was 11.5 days, whereas that of infected sand flies that fed 4 h, 1 day, or 2 days posttreatment on high-dose-treated hamsters (400 μg/kg) was 1.6, 2.1, and 2.7 days, respectively. Infected and uninfected sand flies that blood fed 6 days following low-dose IVM treatment (200 μg/kg) still experienced significantly greater mortality (p < 0.02) than controls. Promastigotes dissected out of surviving flies that fed on IVM-treated hamsters showed typical motility and survival. Moreover, 21.7% of IVM-treated hamsters developed lesions after being fed upon by infected sand flies. L. major promastigotes appeared to be tolerant to ng/mL blood levels of IVM that caused significant mortality for up to 10 days posttreatment in blood-feeding P. papatasi.

Because insulin-like growth factor type I (IGF-I) is reputed to be involved in the endometrial decidualization, we analyzed the expression of IGF-I receptors in an in vitro system of human endometrial stromal cells. Competitive binding studies of both intact stromal cells and membrane preparation indicated the presence of specific components with high affinity for binding IGF-I. Half-maximum displacement was obtained with 2.3 nmol/l native IGF-I, whereas insulin was unable to achieve half-maximum displacement even at higher concentrations. This IGF-I binding component was found to be a saturable protein in respect of the radioligand [125I]IGF-I, with a dissociation constant of 0.16 nmol/l. Affinity cross-linking studies revealed a labelled band of approximate relative molecular mass 135000, corresponding to the known alpha-subunit of IGF-I receptor. This band was significantly inhibited dose-dependently by the IGF-I receptor monoclonal antibody alpha-IR3 or native IGF-I, suggesting that the IGF-I binding component in the membrane of stromal cells has the identity of the alpha-subunit of IGF-I receptor. Cell proliferation in vitro was stimulated by progesterone. Furthermore, progesterone downregulated the [125I]IGF-I binding activity by downregulation of the IGF-I membrane receptor of human endometrial stromal cells. These data show that the IGF-I receptor is a functionally integral component of the stromal cell membrane structure, and its expression might be directly modulated by progesterone and, therefore, might play an important role in the preparation of the stroma for successful embryo implantation.

The primary structures of the a-and ß-chains of the single hemoglobin component from the tomb bat (Taphozous georgianus, Microchiroptera) are presented. After chain separation by re versedphase HPLC the sequences could be determined by automatic gas and liquid phase Edman degradation of the chains and their tryptic peptides. The a-and /3-chains differ from human hemoglobin by 14 and 18 replacements, respectively. Compared to the total number of amino-acid exchanges, the exchange rate in the interhelical regions of the -chains is surprisingly high (25%). It seems unlikely that substitutions at contact positions affect the oxygen binding properties of the hemoglobin. Die Primärstruktur des Hämoglobins des Grabflatterers (Taphozous georgianus, Microchiroptera)