Biochemical characterization of a low salt-adapted extracellular protease from the extremely halophilic archaeon Halococcus salifodinae.

Extracellular proteases from haloarchaea can expand the application fields of proteases. Exploring novel robust proteases is of great importance. An extracellular protease HlyA from Halococcus salifodinae was obtained by heterologous expression, affinity chromatography, in vitro refolding and gel filtration chromatography. Its activity was optimal at 45 °C, pH 9.0 and 1.5-2 M NaCl. Interestingly, although HlyA was from an extremely halophilic archaeon, it retained >75% of maximal activity in a broad NaCl concentration of 0.5-4 M. It displayed relatively stable activities over a wide range of temperature, pH and salinity. Thus, HlyA exhibited good temperature, pH and especially, salinity tolerance. Ca2+, Mg2+ and Sr2+ significantly enhanced the protease activity. HlyA activity was completely inhibited by phenylmethanesulfonyl fluoride (PMSF), suggesting it is a serine protease. HlyA showed good tolerance to some surfactants and organic solvents. The Km and Vmax values of HlyA for azocasein were calculated to be 0.72 mM and 21.98 U/µg, respectively. HlyA was able to effectively degrade several protein substrates, including bovine hemoglobin, casein and azocasein. Generally, HlyA from the extremely halophilic archaeon Hcc. salifodinae is an alkaliphilic and low salt-adapted halolysin with high activity, thus representing an attractive candidate for various industrial uses.

The relationships among impulsivity, anxiety sensitivity and nonsuicidal self-injury characteristics in patients with phobias

Abstract Background: The relationship between impulsivity and nonsuicidal self-injury (NSSI) has been revealed in several mental disorders other than phobias. Objectives: The purpose of this study was to examine the relationships among impulsivity, anxiety sensitivity, and NSSI characteristics in patients with phobias, and to compare these relationships with healthy controls. Methods: The sample of this study consisted of outpatients (n = 109) who had been diagnosed with social phobia, agoraphobia or simple phobia in addition to healthy individuals (n = 51) serving as the control group. Data collection tools were the socio-demographic form, the Barratt Impulsivity Scale (BIS-11), the Inventory of Statements About Self-Injury (ISAS), and the Anxiety Sensitivity Index (ASI-3). Results: Mean BIS-11 and ASI-3 scores in the social phobia and agoraphobia groups were found to be significantly higher than those in the control group. In addition, a positive correlation was found between ISAS and cognitive anxiety sensitivity scores in the agoraphobia and simple phobia groups. Discussion: The study revealed a positive correlation between cognitive anxiety sensitivity and NSSI in both the agoraphobia and simple phobia groups. The results of this study indicate that anxiety sensitivity may play a regulatory role between impulsivity and NSSI in some sub-groups of phobia.

Clusters of sudden unexplained death associated with the mushroom, Trogia venenata, in rural Yunnan Province, China.

INTRODUCTION: Since the late 1970's, time-space clusters of sudden unexplained death (SUD) in northwest Yunnan, China have alarmed the public and health authorities. From 2006-2009, we initiated enhanced surveillance for SUD to identify a cause, and we warned villagers to avoid eating unfamiliar mushrooms. METHODS: We established surveillance for SUD, defined as follows: sudden onset of serious, unexplained physical impairment followed by death in <24 hours. A mild case was onset of any illness in a member of the family or close socially related group of a SUD victim within 1 week of a SUD. We interviewed witnesses of SUD and mild case-persons to identify exposures to potentially toxic substances. We tested blood from mild cases, villagers, and for standard biochemical, enzyme, and electrolyte markers of disease. RESULTS: We identified 33 SUD, a 73% decline from 2002-2005, distributed among 21 villages of 11 counties. We found a previously undescribed mushroom, Trogia venenata, was eaten by 5 of 7 families with SUD clusters compared to 0 of 31 other control-families from the same villages. In T. venenata-exposed persons SUD was characterized by sudden loss of consciousness during normal activities. This mushroom grew nearby 75% of 61 villages that had time-space SUD clusters from 1975 to 2009 compared to 17% of 18 villages with only single SUD (p<0.001, Fisher's exact test). DISCUSSION: Epidemiologic data has implicated T. venenata as a probable cause of clusters of SUD in northwestern Yunnan Province. Warnings to villagers about eating this mushroom should continue.

Postischemic administration of liposome-encapsulated luteolin prevents against ischemia-reperfusion injury in a rat middle cerebral artery occlusion model.

Oxidative stress-induced neuronal cell death has been implicated in neurodegenerative diseases; one such disease is ischemic stroke. Using reactive oxygen species (ROS)-insulted primary neurons, we screened neuroprotectants with clinical potential and then, using ischemia/reperfusion (I/R) model, investigated the anti-ischemic potential of candidate neuroprotectants. Here, we showed that luteolin, isolated from the ripe fruit of Perilla frutescens (L.) Britt, exhibited a neuroprotective action upon the in vitro platform, thus serving as candidate for in vivo pharmacological evaluation. Liposome-encapsulated luteolin produced dramatic preventing effects on I/R-induced behavioral and histological injuries after a 13-day post-ischemic treatment. Furthermore, this phytochemical not only lowered the increased level of mitochondrial ROS but also substantially up-regulated the decreased activity of catalase and glutathione in I/R rat brains. Collectively, luteolin as a neuroprotectant acts by anti-ischemic activity likely through a rebalancing of pro-oxidant/antioxidant status. Its multitarget mechanisms implicate potential effectiveness for clinically treating ischemia stroke.

[Surveillance on iodized salt in China, in 2006].

OBJECTIVE: To understand the national situation of quality and consumption of iodized salt at production and household levels. METHODS: Detailed surveillance method could be found in 'national iodized salt surveillance scheme', issued by MOH in 2004. The iodine concentrations in salt (except some special kinds of salt) were detected by direct titration with national standard of GB/T 13025.7-1999, in which the iodine content in qualified iodized salt was set as between 20 and 50 mg/kg and that in non-iodized salt was set as below 5 mg/kg. RESULTS: At production level, the national lot qualified rate was 98.36% and all the provincial lot qualified rate of production level was over 90%. At household level, the national iodized salt coverage rate of household was 96.87% and the national qualified iodized salt coverage rate was 93.75%. 4 provinces (Tibet, Hainan, Xinjiang and Guangdong) had an iodized salt coverage rate lower than 90%. Further, the qualified iodized salt coverage rate of 5 provinces (Tibet, Hainan, Xinjiang, Guangdong and Qinghai) was below 90%. In 2006,80 counties did not conduct the iodized salt surveillance and non-iodized salt coverage rate of 185 counties was higher than 10%. In the respect of the qualified iodized salt coverage rate at household level, there were about 10 percent lagging behind the national goal that 95% of all the counties in China should achieve virtual elimination of iodine deficiency disorder before 2010. CONCLUSION: At national level,the lot qualified rate at production level and the iodized salt coverage rate at household level maintained comparatively well. However, at county level, there were 75 counties whose iodized salt coverage rate was below 70%.

[Reconstruction of large genomic segment coding for human immunoglobulin kappa chain by meiotic homologous recombination of yeast artificial chromosome].

Meiotic homologous recombination between overlapping yeast artificial chromosome (YAC) can be used to reconstruct larger genomic segment in vivo. We have screened CEPH and Olson human genomic YAC libraries and obtained two YAC clones containing the large genomic segments coding for partial human Ig kappa. In order to reconstruct whole gene cluster of human Ig kappa, two yeast cells containing the different YAC described over were mated and induced to undergo meiotic division and sporulation. Analyzing the results of PCR and Southern blotting, we obtained a clone containing a single recombinant YAC with 400 kb in length, which spans almost the entire gene cluster of human Ig kappa, including 32 V kappa, 5 J kappa, constant domain genes. Besides, we have improved and simplified the traditional method of meiotic recombination between overlapping YACs, and the results indicate the feasibility of this method to reconstruct any larger intact genomic segments.