Vacciniumusneoides (Ericaceae), a new species from Yunnan, China.

Vacciniumusneoides (Ericaceae), a new species from Fugong County of Yunnan Province, China is described and illustrated. This new species belongs to Vacciniumsect.Calcicolus and is most similar to V.brachyandrum, but differs in its branches hanging down, much smaller leaf blades, shorter inflorescences and pedicels, non-glandular tomentellate or densely pubescent inflorescence rachis and pedicels, densely white-pubescent hypanthium and pilose filaments.

Coenurosis of Yak, Bos grunniens, caused by Taenia multiceps: A Case Report with Molecular Identification in Qinghai Tibetan Plateau Area, China.

Coenurosis is an important zoonotic helminthic disease caused by the larval stage of the tapeworm Taenia multiceps. This parasite typically infects the brain of the intermediate hosts, including sheep, goat, cattle and even humans. We report a case of T. multiceps infection in a yak confirmed by clinical symptoms, morphological characteristics, and molecular and phylogenetic analyses. The coenurus was thin-walled, whitish, and spherical in shape with a diameter of 10 cm. The parasite species was identified as T. multiceps by PCR amplification and sequencing of the 18S rRNA, cox1 and nad1 genes. Three gene sequences all showed high homology (all above 97%) with the reference sequences from different hosts. Moreover, phylogenetic reconstructions with the 3 published Taenia gene sequences confirmed that the Qinghai yak isolate was closely related to T. multiceps. Although there are advanced diagnosis and treatment methods for coenurosis, early infection is difficult to diagnose. Importantly, the findings of yak infection case should not be ignored due to its zoonotic potential.

Improving thermostability of (R)-selective amine transaminase from Aspergillus terreus through introduction of disulfide bonds.

To improve the thermostability of (R)-selective amine transaminase from Aspergillus terreus (AT-ATA), we used computer software Disulfide by Design and Modelling of Disulfide Bonds in Proteins to identify mutation sites where the disulfide bonds were most likely to form. We obtained three stabilized mutants (N25C-A28C, R131C-D134C, M150C-M280C) from seven candidates by site-directed mutagenesis. Compared to the wild type, the best two mutants N25C-A28C and M150C-M280C showed improved thermal stability with a 3.1- and 3.6-fold increase in half-life (t1/2 ) at 40 °C and a 4.6 and 5.1 °C increase in T5010 . In addition, the combination of mutant R131C-D134C and M150C-M280C displayed the largest shift in thermostability with a 4.6-fold increase in t1/2 at 40 °C and a 5.5 °C increase in T5010 . Molecular dynamics simulation indicated that mutations of N25C-A28C and M150C-M280C lowered the overall root mean square deviation for the overall residues at elevated temperature and consequently increased the protein rigidity. The stabilized mutation of R131C-D134C was in the region of high mobility and on the protein surface, and the disulfide bond constraints the flexibility of loop 121-136.

Analysis of EPA and DHA in the viscera of marine fish using gas chromatography.

The viscera of 10 kinds of marine fishes were collected for fish oil extraction and detection of DHA and EPA, two most important polyunsaturated fatty acids. The fish oil extraction ratio for the evaluated fishes varied from 0.95% to 10.18% (wt%). Pseudosciaena crocea presented the highest fish oil yield, followed by Mustelus manazo, Hippoglossus and Sciaenopsocellatus. A gas chromatography method was then established for analysis of EPA/DHA. The EPA concentration (in methyl ester form) in the fish oil varied from 1.39 to 10.65(mg/g). Epinephelus awoara presented the highest EPA concentration (p<0.05), followed by Epinephelussp, Sciaenopsocellatus and Hippoglossus. The DHA concentration (in methyl ester form) in the fish oil varied from 0.58 to 37.02 (mg/g). Epinephelus awoara presented the highest DHA concentration (p<0.05), followed by Sciaenopsocellatus, Pseudosciaena crocea and Hippoglossus. No strict positive correlation between the EPA/DHA concentration and the sea depth where the fish live was observed. The fishes living in middle depth presented highest EPA/DHA concentration.

[Cloning and Expression of Tibetan Sheep-origin Echinococcus granulosus Antigen B Gene and Protein Identification Using Immunological Method].

Objective: To clone and express the Tibetan Sheep-origin Echinococcus granulosus Antigen B8/2 Gene, and immunologically identify the encoded protein. Methods: The cDNA of EgAgB8/2 gene was amplified by RT-PCR. The prokaryotic expression vector pET-EgAgB8/2 was constructed and transformed into E. coli BL21（DE3） for expression. Proteins were extracted, separated in SDS-PAGE and identified by Western blotting. Results: The cloned EgAgB8/2 gene was 335 bp in length, and had a 98%-100% sequence homology with the reported cDNA sequence of EgAgB8/2, indicating the successful construction of the pET-EgAgB8/2 vector. SDS-PAGE revealed large amount of proteins in supernatant. Western blotting further confirmed the expression of the target protein. Conclusion: The EgAgB8/2 gene of Tibetan Sheep-origin in Qinghai is successfully cloned, and the constructed pET-EgAgB8/2 vector can be used to express the target protein.

Analysis of apoptosis induced by perfluorooctane sulfonates (PFOS) in mouse Leydig cells in vitro.

To explore the possible mechanism of perfluorooctane sulfonates (PFOS's) reproductive toxicity, mouse Leydig cells cultured in vitro were exposed to a serial concentration of PFOS for four more days of culture. Apoptosis during the process was checked. After 24 h, apoptosis occurred to all of the groups ≥ 50 µg/mL PFOS. After 72 h, 37.5 µg/mL dose also showed apoptosis, and the most apoptosis signals, averagely 18 per well, were observed in 62.5 µg/mL dose group. An increase in ROS (p < 0.05) and a decrease of mitochondrial membrane potential (p < 0.01) was confirmed in those groups with ≥ 12.5 µg/mL dose. ROS levels peaked in 50 µg/mL and 62.5 µg/mL groups, nearly two-folds higher than control. PFOS was also observed to down-regulate the protein expression of Bcl-2 and to up-regulate that of Bax. The apoptosis induced by PFOS in mouse Leydig cells was shown to be related to mitochondrially mediated pathways and to involve oxidative stress.

Effects of subchronic samarium exposure on the histopathological structure and apoptosis regulation in mouse testis.

To evaluate the reproductive toxicity of samarium, a widely used rare earth element, male ICR mice were orally exposed to samarium nitrate for 90 days for lesion evaluation in the testis. Decreased organ coefficients, disorganized seminiferous tubules, and decreased spermatogenic cells and sperm of the testis were observed extensively in the treated groups, indicating that the testis is a target organ of samarium. Electron microscopy confirmed that the lesions inside the spermatogenic cells and sperm mainly included mitochondrial swelling, mitochondrial vacuolization, fuzzy nuclear membranes, and marginated chromatin. Increased spermatogenic cell apoptosis rate in the testis was confirmed with a TUNEL assay. And expression up-regulation of p53 and Bax, and down-regulation of Bcl-2 were observed (p<0.05), indicating the apoptosis is related to p53 mediated pathway.

[Species identification of Echinococcus isolates collected from canines and Tibetan foxes in Chengduo County, Qinghai Province].

OBJECTIVE: To identify Echinococcus isolates collected from Tibetan foxes(Vulpes ferrilata) and dogs in Chengduo county, Yushu Prefecture, Qinghai Province. METHODS: Six Tibetan foxes and 6 Tibetan dogs died accidently. Small intestines were dissected from the animals. The adult tap-worms were collected by sedimentation technique. The worms were stained with borax carmine and observed under microscope. The isolates were identified initially by morphology and the infection intensity for each animal was calculated. Eight isolates of E. multilocularis and 2 isolates of E. shiquicus were selected for the extraction of total DNA. The mitochondrion DNA CO I gene was amplified with specific primers by PCR, then sequenced and analyzed. RESULTS: E. multilocularis and E. shiquicus were found. Two out of 6 Tibetan foxes were infected with E. multilocularis, the infection intensity was 1,640 and 839. One Tibetan fox was infected by E. shiquicus with an infection intensity of 833. Two Tibetan dogs were infected with E. multilocularis, and the infection intensity was 10,195 and 78, respectively. The obtained partial sequences of CO I gene were 450 bp. The CO I gene from 8 isolates of E. multilocularis shared 100% homology with the isolates collected from Tibetan dogs in Sichuan Province (Accession No. AB461417). The CO I gene from 2 isolates of E. shiquicus showed high sequence homology (99.2%) with the isolates collected from Ochotona curzoniae in Shiqu County, Sichuan Province(Accession No. AB159136). CONCLUSION: E. multilocularis and E. shiquicus have been identified in the small intestines of wild foxes, and E. multilocularis in Tibetan dogs.