Distribution and altitudinal structuring of phlebotomine sand flies (Diptera: Psychodidae) in southern Anatolia, Turkey: their relation to human cutaneous leishmaniasis.

The two Old World genera, Phlebotomus and Sergentomyia, were both recorded in southern Anatolia in Turkey. Phlebotomus species predominated and comprised about 93% of the entire collection (3,172 specimens). Out of the sixteen species identified, two belonged to the genus Sergentomyia: S. dentata and S. theodori. The remaining fourteen species in the genus Phlebotomus were grouped under four subgenera including some species that are elsewhere known to act as vectors of human cutaneous leishmaniasis. Most of the Phlebotomus were P. tobbi (32.5%), but P. papatasi, P. transcaucasicus, P. halepensis, P. galilaeus, P. sergenti, P. syriacus, P. neglectus, P. simici, P. alexandri, P. similis, P jacusieli, P. perfiliewi, and P. brevis were also identified. There were two associations of sand fly fauna with altitudinal gradient; the first one at relatively higher altitudes and the second one at lower altitudes. The transition between these two assemblages was within the range of 800-1,000 m. It is likely that Adana and Hatay provinces are transitional areas between western and eastern Anatolia. Mountains do not appear to be important geographical barriers for sand fly distribution. We also found that the proven vector P. sergenti is a widely distributed species throughout southern Anatolia and this species, together with its closely related species P. similis, shows sympatry in Konya Province.     

Ganglioside biosynthesis in Golgi apparatus of rat liver. Stimulation by phosphatidylglycerol and inhibition by tunicamycin

Golgi vesicles were isolated and purified from rat liver, in which the specific activities of glycosyltransferases (e.g. GM3:CMP-NeuAc sialyltransferase, GD3 synthase; GM3:UDP-GalNAc galactosaminyltransferase, GM2 synthase) were 50-60-times enriched relative to microsomes or total homogenate. Synthesis of gangliosides GM2 and GM1 in such Golgi vesicles is, in the absence of any detergents, stimulated 6-fold and 20-fold respectively by phosphatidylglycerol. Other phospholipids like phosphatidylethanolamine and phosphatidylserine are also significantly stimulatory. With 50 micrograms Golgi protein and 1 nmol UDP-GalNAc, optimal stimulation of GM2 synthase was obtained with 20 micrograms of phosphatidylglycerol and 7.5 nmol of the lipid acceptor GM3. Under the same experimental conditions this stimulation exceeds (by about 40%) that obtained with optimal amount (200 micrograms) of the detergent octylglucoside. Phosphatidylglycerol, on the other hand, has virtually no stimulatory activity on the synthesis of ganglioside GD3 either in the presence of Mg2+ or Mn2+, indicating that facilitation by phospholipid of GM3 transport into Golgi vesicles was not the basis of stimulation of GM2 synthesis. Tunicamycin inhibits the synthesis of gangliosides GM2 and GM1 in isolated Golgi vesicles, but only in the absence of detergents. In the presence of phosphatidylglycerol, GM2 synthesis, for example, was inhibited by 60% by 2 micrograms tunicamycin and more than 85% by 10 micrograms tunicamycin, per 50 micrograms Golgi membrane protein. The inhibition was stronger on GM1 synthesis: 85% with 2.5 micrograms of the antibiotic. The dependence on phosphatidylglycerol and the degree of inhibition by tunicamycin of the synthetic activities are strictly dependent on the intactness of the Golgi vesicles: both phenomena become increasingly less evident when the vesicles are pelleted, and frozen and thawed several times, and completely disappear when the vesicles are solubilized by detergents or disrupted by ultrasonication. Furthermore, tunicamycin inhibition is reversible by increased concentration of phosphatidylglycerol. All these results indicate that phosphatidylglycerol does not stimulate, and tunicamycin does not inhibit, the transferases themselves; rather, the two opposing effects might relate to carrier-mediated transport, e.g. of nucleotide sugars, across Golgi vesicles.     

Synthesis,Biological Evaluation,and Molecular Modeling Studies of New 1,3,4-Thiadiazole Derivatives as Potent Antimicrobial Agents

In this work, the synthesis, characterization, and biological activities of a new series of 1,3,4-thiadiazole derivatives were investigated. The structures of final compounds were identified using ¹H-NMR, ¹³C-NMR, elemental analysis, and HRMS. All the new synthesized compounds were then screened for their antimicrobial activity against four types of pathogenic bacteria and one fungal strain, by application of the MIC assays, using Ampicilin, Gentamycin, Vancomycin, and Fluconazole as standards. Among the compounds, the MIC values of 4 and 8 μg/mL of the compounds 3f and 3g , respectively, are remarkable and indicate that these compounds are good candidates for antifungal activity. The docking experiments were used to identify the binding forms of produced ligands with sterol 14-demethylase to acquire insight into relevant proteins. The MD performed about 100 ns simulations to validate selected compounds’ theoretical studies. Finally, using density functional theory (DFT) to predict reactivity, the chemical characteristics and quantum factors of synthesized compounds were computed. These results were then correlated with the experimental data. Furthermore, computational estimation was performed to predict the ADME properties of the most active compound 3f .     

Dog-DAT: a direct agglutination test using stabilized, freeze-dried antigen for the serodiagnosis of canine visceral leishmaniasis

Abstract We have evaluated the use of an improved direct agglutination test (DAT) based on stable, freeze-dried antigen for the detection of anti- Leishmania antibodies in canine serum samples. With a cut-off value of 1:640, the sensitivity of the DAT was shown to be 100% and the specificity of the test was 98.8%.     

Echinococcus granulosus: host lymphocyte transformation by parasite antigens.

Lymphocyte transformation, measured by in vitro tritiated thymidine incorporation, and indirect hemagglutination tests were carried out on hydatid patients and normal individuals using sheep and human hydatid fluid or scolex antigens. The hydatid patients showed statistically significant lymphocyte transformation with human and sheep hydatid fluid or scolex antigens when compared to normal individuals. The indirect hemagglutination tests resulted in high titers of antibody with sheep or human hydatid fluid antigens, while very low titers were obtained with scolex antigens. Unlike in the indirect hemagglutination test, the source of the antigen, scolex or fluid, was not of consequence in the lymphocyte transformation test. Furthermore, there was no correlation between the results of the serologic and lymphocyte transformation tests, since some patients with very high lymphocyte stimulation indices produced low indirect hemagglutination titers and vice versa. Similar results were obtained from rabbits which were immunized with sheep hydatid fluid or scolex extracts. The skin tests were of the immediate type of hypersensitivity reactions. Delayed skin reactions did not occur in spite of the presence of sensitized lymphocytes in the blood of the immunized rabbits.     

Human endothelial cell growth and phenotypic expression on three dimensional poly(lactide-co-glycolide) sintered microsphere scaffolds for bone tissue engineering

Bone tissue engineering offers promising alternatives to repair and restore tissues. Our laboratory has employed poly(lactide-co-glycolide) PLAGA microspheres to develop a three dimensional (3-D) porous bioresorbable scaffold with a biomimetic pore structure. Osseous healing and integration with the surrounding tissue depends in part on new blood vessel formation within the porous structure. Since endothelial cells play a key role in angiogenesis (formation of new blood vessels from pre-existing vasculature), the purpose of this study was to better understand human endothelial cell attachment, viability, growth, and phenotypic expression on sintered PLAGA microsphere scaffold. Scanning electron microscopy (SEM) examination showed cells attaching to the surface of microspheres and bridging the pores between the microspheres. Cell proliferation studies indicated that cell number increased during early stages and reached a plateau between days 10 and 14. Immunofluorescent staining for actin showed that cells were proliferating three dimensionally through the scaffolds while staining for PECAM-1 (platelet endothelial cell adhesion molecule) displayed typical localization at cell-cell contacts. Gene expression analysis showed that endothelial cells grown on PLAGA scaffolds maintained their normal characteristic phenotype. The cell proliferation and phenotypic expression were independent of scaffold pore architecture. These results demonstrate that PLAGA sintered microsphere scaffolds can support the growth and biological functions of human endothelial cells. The insights from this study should aid future studies aimed at enhancing angiogenesis in three dimensional tissue engineered scaffolds.     

From agro-industrial wastes to single cell oils: a step towards prospective biorefinery

The reserves of fossil-based fuels, which currently seem sufficient to meet the global demands, is inevitably on the verge of exhaustion. Contemporary raw material for alternate fuel like biodiesel is usually edible plant commodity oils, whose increasing public consumption rate raises the need of finding a non-edible and fungible alternate oil source. In this quest, single cell oils (SCO) from oleaginous yeasts and fungi can provide a sustainable alternate of not only functional but also valuable (polyunsaturated fatty acids (PUFA)-rich) lipids. Researches are been increasingly driven towards increasing the SCO yield in order to realize its commercial importance. However, bulk requirement of expensive synthetic carbon substrate, which inflates the overall SCO production cost, is the major limitation towards complete acceptance of this technology. Even though substrate cost minimization could make the SCO production profitable is uncertain, it is still essential to identify suitable cheap and abundant substrates in an attempt to potentially reduce the overall process economy. One of the most sought-after in-expensive carbon reservoirs, agro-industrial wastes, can be an attractive replacement to expensive synthetic carbon substrates in this regard. The present review assess these possibilities referring to the current experimental investigations on oleaginous yeasts, and fungi reported for conversion of agro-industrial feedstocks into triacylglycerols (TAGs) and PUFA-rich lipids. Multiple associated factors regulating lipid accumulation utilizing such substrates and impeding challenges has been analyzed. The review infers that production of bulk oil in combination to high-value fatty acids, co-production strategies for SCO and different microbial metabolites, and reutilization and value addition to spent wastes could possibly leverage the high operating costs and help in commencing a successful biorefinery. Rigorous research is nevertheless required whether it is PUFA-rich oil production (for competing with algal omega oils) or neutral bulk oil production (for overcoming yield limitations and managing process economy) to establish this potential source as future resource.     

Biodiesel from microalgae beats bioethanol

Renewable biofuels are needed to displace petroleum-derived transport fuels, which contribute to global warming and are of limited availability. Biodiesel and bioethanol are the two potential renewable fuels that have attracted the most attention. As demonstrated here, biodiesel and bioethanol produced from agricultural crops using existing methods cannot sustainably replace fossil-based transport fuels, but there is an alternative. Biodiesel from microalgae seems to be the only renewable biofuel that has the potential to completely displace petroleum-derived transport fuels without adversely affecting supply of food and other crop products. Most productive oil crops, such as oil palm, do not come close to microalgae in being able to sustainably provide the necessary amounts of biodiesel. Similarly, bioethanol from sugarcane is no match for microalgal biodiesel.     

Biosorption of chromium(VI) from aqueous solution by cone biomass of Pinus sylvestris

Biosorption of chromium(VI) on to cone biomass of Pinus sylvestris was studied with variation in the parameters of pH, initial metal ion concentration and agitation speed. The biosorption of Cr(VI) was increased when pH of the solution was decreased from 7.0 to 1.0. The maximum chromium biosorption occurred at 150 rpm agitation. An increase in chromium/biomass ratio caused a decrease in the biosorption efficiency. The adsorption constants were found from the Freundlich isotherm at 25 degrees C. The cone biomass, which is a readily available biosorbent, was found suitable for removing chromium from aqueous solution.