Estimating the Population Size and Genetic Diversity of Amur Tigers in Northeast China

Over the past century, the endangered Amur tiger (Panthera tigris altaica) has experienced a severe contraction in demography and geographic range because of habitat loss, poaching, and prey depletion. In its historical home in Northeast China, there appears to be a single tiger population that includes tigers in Southwest Primorye and Northeast China; however, the current demographic status of this population is uncertain. Information on the abundance, distribution and genetic diversity of this population for assessing the efficacy of conservation interventions are scarce. We used noninvasive genetic detection data from scats, capture-recapture models and an accumulation curve method to estimate the abundance of Amur tigers in Northeast China. We identified 11 individual tigers (6 females and 5 males) using 10 microsatellite loci in three nature reserves between April 2013 and May 2015. These tigers are confined primarily to a Hunchun Nature Reserve along the border with Russia, with an estimated population abundance of 9–11 tigers during the winter of 2014–2015. They showed a low level of genetic diversity. The mean number of alleles per locus was 2.60 and expected and observed heterozygosity were 0.42 and 0.49, respectively. We also documented long-distance dispersal (~270 km) of a male Amur tiger to Huangnihe Nature Reserve from the border, suggesting that the expansion of neighboring Russian populations may eventually help sustain Chinese populations. However, the small and isolated population recorded by this study demonstrate that there is an urgent need for more intensive regional management to create a tiger-permeable landscape and increased genetic connectivity with other populations.     

Thawed human hepatocytes in primary culture.

In drug metabolism studies, isolated and cultured human hepatocytes provide a useful model for overcoming the difficulty of extrapolating from animal data. In vitro studies with human hepatocytes are scarce because of the lack of livers and suitable methods of storage. After developing a new method for cryopreservation of human hepatocytes, we evaluated the effects of deep freezing storage on their viability, morphology, and functional and toxicological capabilities in classical culture conditions. Freshly isolated human hepatocytes were cryopreserved in medium containing 10% Me2SO and 20% fetal calf serum, using a Nicool ST20 programmable freezer (-1.9 degrees C/min for 18 min and -30 degrees C/min for 4 min). Cells were stored in liquid nitrogen. Viability of thawed human hepatocytes was 50-65% as assessed by erythrosin exclusion test prior to purification on a Percoll density gradient. Morphological criteria showed that thawed human hepatocytes require an adaptation period to the medium after seeding. Functional assessments showed that human hepatocytes which survive freezing and thawing preserve their protein synthesis capabilities and are able to secrete a specific protein, anionic peptidic fraction, which is involved in the hepatic uptake of bile-destined cholesterol. We then studied Midazolam biotransformation to test metabolic functions, and erythromycin toxicity by Neutral Red test (cell viability) and 3-(4,5-dimethylthiazol-2-yl)-diphenyl tetrazolium bromide test (cell metabolism). All of these experiments indicated that thawed human hepatocytes should be used 38 h after seeding for optimum recovery of their functions: membrane integrity, protein synthesis, and stabilization of drug metabolism enzymes.     

全沟硬蜱体内伯氏疏螺旋体的分离及特征

本文报道从黑龙江省全沟硬蜱分离的伯氏疏螺旋体H7株的特征。H7株细胞长9．8—26．5μm,宽0．1 3—0．35μm,有l—11个波,波长1．2—3．Oμm,波幅0．59一1．13μm,两端尖乩每端有7根鞭毛,菌体左旋。体外培养最适温度为31℃,具有2lk、32k、34k主要结构和抗原蛋白,能与新疆及黑龙江莱姆病人血清反应。这些结果表明,该菌株具备伯氏疏螺旋体的特征,它是与其它地区或媒介分离株不同的“亚型”。     

Petrocodon tongziensis (Gesneriaceae), a new species from limestone areas in Guizhou,China based on morphological and molecular evidence

Petrocodon tongziensis R.B.Zhang & F.Wen, a new species from northern Guizhou province, China, is described and illustrated based on molecular and morphological evidence. The new species was found growing in crevices and on tufa of moist surfaces of limestone hills in Tongzi County. A maximum parsimony (MP) analysis based on the combined ITS and trnL‐F DNA regions showed that the new species falls within a large polytomy within Petrocodon, but is resolved as most closely related to an unidentified species (WF2014) and these two taxa are in turn resolved as sister to Petrocodon hunanensis X.L.Yu & Ming Li. This is congruent with the fact that both P. hunanensis and P. tongziensis have four fertile stamens, a character state likely to be an ancestral state distinguishing this clade from the rest of Petrocodon. Petrocodon tongziensis differs from P. hunanensis by lacking a terrestrial stem, as well as by the number of bracts, presence of bracteoles, shape of the lobes of the upper lip, and reduced number and length of staminodes.     

Simvastatin Inhibited the Apoptosis of PC12 Cells Induced by 1-Methyl-4-Phenylpyridinium Ion via Inhibiting Reactive Oxygen Species Production

In the present study, we investigated the neuroprotection of simvastatin in PC12 cells following 1-methyl-4-phenylpyridinium ion (MPP+) neurotoxicity. Simvastatin inhibited the decrease of cell viability induced by MPP+ in PC12 cells. The damage of PC12 cells in morphology was alleviated and the apoptotic rates were decreased due to simvatatin pretreatment against MPP+ cytotoxicity. The reactive oxygen species production exposure to MPP+ was inhibited by simvatatin in PC12 cells. So simvastatin may be of therapeutic benefit for PD patients.     

mTOR inhibitor INK128 attenuates dextran sodium sulfate-induced colitis by promotion of MDSCs on Treg cell expansion

Accumulating evidence has shown that mammalian target of rapamycin (mTOR) pathway and myeloid-derived suppressor cells (MDSCs) are involved in pathogenesis of inflammatory bowel diseases (IBDs). INK128 is a novel mTOR kinase inhibitor in clinical development. However, the exact roles of MDSCs and INK128 in IBD are unclear. Here, we showed that the INK128 treatment enhanced the resistance of mice to dextran sodium sulfate (DSS)–induced colitis and inhibited the differentiation of MDSCs into macrophages. Moreover, interferon (IFN)-α level was elevated in INK128-treated colitis mice. When stimulated with IFN-α in vitro, MDSCs showed a superior immunosuppression activity. Of note, the regulatory T cells (Tregs) increased but Th1 cells decreased in INK128-treated colitis mice. These results indicate that mTOR inhibitor INK128 attenuates DSS-induced colitis via Treg expansion promoted by MDSCs. Our work provides a new evidence that INK128 is potential to be a therapeutic drug on DSS-induced colitis via regulating MDSCs as well as maintaining Treg expansion.