Peptidases of Trichobilharzia regenti (Schistosomatidae) and its molluscan host Radix peregra S. Lat. (Lymnaeidae): construction and screening of cDNA library from intramolluscan stages of the parasite

Trichobilharzia regenti is a neurotropic bird schistosome,causing cercarial dermatitis in humans. In this study, ZAP cDNA expression library from Radix peregra s. lat. hepatopancreases containing intramolluscan stages of T. regenti was constructed and screened using PCR with specific and degenerate primers, designed according to previously described serine and cysteine peptidases of other parasite species. Full-length sequences of cathepsins B1 and L, and two serine peptidases, named RpSP1 and RpSP2, were obtained.The protein-protein BLAST analysis and parallel control reactions with template from hepatopancreases of T. regenti non-infected snails revealed that only cathepsin B1 was of parasite origin. The remaining sequences were derived from the snail intermediate host, which implies that the initial source of parasite mRNA was contaminated by snail tissue.Regardless of this contamination, the cDNA library remains an excellent molecular tool for detection and identification of bioactive molecules in T. regenti cercariae.     

Influence of noncellulosic contents on nano scale refinement of waste jute fibers for reinforcement in polylactic acid films

In the present study, nanofibrils of cellulose are extracted from waste jute fibers using high energy planetary ball milling process in wet condition. The rate of refinement of untreated fibers having non-cellulosic contents was found slower than treated fibers due to strong holding of fiber bundles by non-cellulosic contents. At the end of three hours of wet milling, untreated fibers were refined to the size of 850 nm and treated fibers were refined to the size of 443 nm. In the subsequent stage, composite films of poly lactic acid (PLA) were prepared by solvent casting with 3 wt% loading of untreated jute nanofibrils, treated jute nanofibrils and microcrystalline cellulose. The influence of non-cellulosic contents on mechanical properties of PLA films are investigated based on results of tensile test, dynamic mechanical analysis and differential scanning calorimetry. The maximum improvement was observed in case of treated jute nanofibril/PLA composite film where initial modulus and tensile strength increased by 207.69 % and 168.67 %, respectively as compared to neat PLA film. These improvements are attributed to the increased interaction of treated jute nanofibrils with PLA matrix due to their higher precentage of cellulosic contents and mechanically activated surface.     

阿拉善双峰驼驼乳蛋白中氨基酸的含量及营养价值

对10峰阿拉善双峰驼第一次分娩后、泌乳时间90d时驼乳中的必需氨基酸含量及其营养价值进行了研究。结果表明,在泌乳90d时所挤驼乳蛋白中Thr,Val,Met,Ile,Leu,Phe和Lys必需氨基酸的含量分别为4.52,6.20,3.16,5.61,9.48,4.73,7.75g/100g。驼乳蛋白质中的必需氨基酸构成和FAO/WHO的推荐值十分相近,驼乳蛋白质对人体具有很高的营养价值。     

大麦杂种后代的赤霉病抗性变异及抗性与棱性的关系

本文用５个二棱大麦“抗性强×抗性中”组合的Ｆ_６集团和４个“二棱抗性弱×六棱抗性中”组合的１１３个Ｆ_７系统以及５０对二棱和六棱近等基因系，进行了大麦赤霉病的抗性鉴定及遗传分析，结果表明：大麦赤霉病抗性受具有累加效应的微效多基因系统的控制，其广义遗传力为０．６０；二棱系统的抗性比六棱系统强，但控制抗性的基因和棱型基因之间连锁的可能性很小。     

Marihuana components: effects of smoking on delta-9-tetrahydrocannabinol and cannabidiol

Cigarettes impregnated with various preparations of Delta(9)-tetrahydro-cannabinol (Delta(9)-THC) and cannabidiol were artificially smoked, and the smoke was analyzed by means of gas chromatography and a combination of gas chromatography and mass spectrometry. Retention of the two test substances in smoke was 21 to 23 percent of the starting amount. The ratio of Delta(9)-THC to cannabidiol in smoke is different from that in starting material. It is suggested that these differences are the result of partial cyclization of the cannabidiol to Delta(9)-THC. An increase in the percentage of cannabinol in smoke is the result of a partial dehydrogenation drogenation of Delta(9)-THC or cannabidiol. No evidence for the isomerization of Delta(9)-THC to Delta(8)-THC or for the formation of new pyrolyzed products was found.     

Induction of heme oxygenase-1 by Macleaya cordata extract and its constituent sanguinarine in RAW264.7 cells

Macleaya cordata (plume poppy) is used in traditional Chinese medicine for its anti-inflammatory and antibacterial activities. In this study, we examined whether M. cordata extract and/or its major alkaloid constituents, protopine, allocryptopine, sanguinarine and chelerythrine activate the Nrf2 signalling pathway which regulates the expression of cytoprotective enzymes including heme oxygenase-1 (HO-1) and thioredoxin 1. In murine macrophage RAW264.7 cells, M. cordata extract increased both mRNA and protein levels of HO-1. Of the alkaloids examined, only sanguinarine appeared to be responsible for these effects. At the concentration of 2 μM, sanguinarine induced nuclear accumulation of Nrf2, increased the expression of Hmox1 gene encoding HO-1 and elevated HO-1 protein levels. Sanguinarine-induced Hmox1 mRNA expression was suppressed by SB203580, a pharmacologic inhibitor of p38 mitogen-activated protein kinases (p38 MAPKs). The upregulation of HO-1 in RAW264.7 cells by sanguinarine was, however, accompanied by decrease in cell viability. Nonetheless, sanguinarine at micromolar, non-cytotoxic concentrations elevated protein levels of HO-1 and thioredoxin 1 in primary cultures of human hepatocytes. We conclude that sanguinarine may, under appropriate conditions, increase the capacity of the enzymatic antioxidant defence system via activation of the p38 MAPK/Nrf2 pathway.     

Reinforcement of wet milled jute nano/micro particles in polyvinyl alcohol films

Textile industry generate significant amount of waste fibres in form of short lengths during mechanical processing. However these short fibres possess excellent properties suitable for many other applications. The objective of this work was to use them for the preparation of nanoparticles/nanofibres as fillers in biodegradable composite applications such as food packaging, agriculture mulch films, automotive plastics, etc. The present paper concerns with jute fibres as a source of nanocellulose for reinforcement of PVA mulch films. Jute fibres were first refined to micro/nanoscale particles in form of nanofibrillar cellulose (NFC) by high energy planetary ball milling process in dry and wet condition. Wet milling was observed more efficient than dry milling in terms of unimodality of size distribution with reduction in size below 500 nm after milling for 3 hours. Later the obtained particles were used as fillers in Poly vinyl alcohol (PVA) films and their reinforcement evaluated based on thermal properties. It was observed that glass transition temperature (T_g) of PVA films improved from 84.36 °C to 95.22 °C after addition of 5 % jute particles without affecting % crystallinity and melting temperature (T _m) of PVA. Dynamic mechanical analysis of composite films with 5 % jute particles showed higher value of 14×10⁸ Pa for storage modulus in comparison to 9×10⁸ Pa of neat composite film. The percolation effect was observed more above glass transition temperature which consequently resulted in improved transfer of stiffness from jute particles to PVA matrix above 50 °C. The percolation phenomena also explained the improvement in thermal stability by 10 °C for every increased loading of jute particles due to formation of hydrogen bonds with PVA matrix.     

Surface modification of polymer optical fibers for enhanced side emission behavior

The polymer optical fiber with trade name Flexi was used in this research, because of its flexibility and the range of diameters available in the market. These fibers were dyed using commercial disperse dye under various conditions of dye concentration and dyeing time. Samples were analyzed for side emission of light with the use of an instrument which was specifically designed for the measurement of this nature. The results showed that the dye penetration is dependent on time, if dye concentration and temperature are kept constant. After 40 min of dyeing, the fiber core showed an increase in side emission with lower loss due to attenuation. Excessive time in the hot conditions also degraded the fiber, so that the fiber became very stiff and brittle. Fibers were also subjected to heat, in the form of boiling water bath, for selected periods of time, and it was found that the effect was similar to that of the prior experiments. Surface treatment of Flexi fibers was carried out using ethyl acetate as an etching agent, to possibly accept more disperse dye on the fiber surface. The results after dyeing showed a more significant improvement in both side emission and attenuation of light.     

Changes in the nutritional parameters of muscles of the common carp (Cyprinus carpio) and the silver carp (Hypophthalmichthys molitrix) following environmental exposure to cyanobacterial water bloom

The present study evaluated the effect of naturally developing cyanobacteria on the composition of muscles of two commercially important freshwater fish species. Fish were exposed to cyanobacterial biomass including Microcystis aeruginosa and Microcystis ichthyoblabe for 4 weeks. Then, they were transferred to dechlorinated potable water without any cyanobacteria for another 4-week period, thus modelling their preparation for consumers. Samples of muscles were collected every week during exposure and subsequent stay in dechlorinated potable water. The cyanobacterial water bloom of 3.9–6 × 10⁵ cells mL⁻¹ (133–383 μg g⁻¹ of total MC DW) induced statistically significant effects only in the content of fatty acids ( P <0.05; P <0.01) in the common carp ( Cyprinus carpio ), while all studied parameters including the content of dry matter and fat ( P <0.01), proteins ( P <0.05), fatty acid composition ( P <0.05; P <0.01) and some amino acids ( P <0.05) were affected in the silver carp ( Hypophthalmichthys molitrix ). This study has shown that cyanobacteria in the environment of commercially produced fish may decrease the dietetic value of fish muscles.