Up-regulation of neutrophil activating protein in Helicobacter pylori under high-salt stress: Structural and phylogenetic comparison with bacterial iron-binding ferritins

It is generally accepted that most gastrointestinal diseases are probably caused by the bacterial pathogen Helicobacter pylori (H. pylori). In this study we have focused on the comparison of protein expression profiles of H. pylori grown under normal and high-salt conditions by a proteomics approach. We have identified about 190 proteins whose expression levels changed after growth at high salt concentration. Among these proteins, neutrophil-activating protein (NapA) was found to be consistently up-regulated under osmotic stress brought by high salts. We have investigated the effect of high salt on secondary and tertiary structures of NapA by circular dichroism spectroscopy followed by analytical ultracentrifugation to monitor the change of quaternary structure of recombinant NapA with increasing salt concentration. The loss of iron-binding activity of NapA coupled with noticeable energetic variation in protein association of NapA as revealed by isothermal titration calorimetry was found under high salt condition. The phylogenetic tree analysis based on sequence comparison of 16 protein sequences encompassing NapA proteins and ferritin of H. pylori and other prokaryotic organisms pointed to the fact that all H. pylori NapA proteins of human origin are more homologous to NapA of Helicobacter genus than to other bacterial NapA. Based on computer modeling, NapA proteins from H. pylori of human isolates are found more similar to ferritin from H. pylori than to NapA from other species of bacteria. Taken together, these results suggested that divergent evolution of NapA and ferritin possessing dissimilar and diverse sequences follows a path distinct from that of convergent evolution of NapA and ferritin with similar dual functionality of iron-binding and ferroxidase activities.     

Nutritional strategies to modulate inflammation and oxidative stress pathways via activation of the master antioxidant switch Nrf2

The nuclear factor E2-related factor 2 (Nrf2) plays an important role in cellular protection against cancer, renal, pulmonary, cardiovascular and neurodegenerative diseases where oxidative stress and inflammation are common conditions. The Nrf2 regulates the expression of detoxifying enzymes by recognizing the human Antioxidant Response Element (ARE) binding site and it can regulate antioxidant and anti-inflammatory cellular responses, playing an important protective role on the development of the diseases. Studies designed to investigate how effective Nrf2 activators or modulators are need to be initiated. Several recent studies have shown that nutritional compounds can modulate the activation of Nrf2–Keap1 system. This review aims to discuss some of the key nutritional compounds that promote the activation of Nrf2, which may have impact on the human health.     

二倍体马铃薯耐盐品种鉴定的生理指标测定

以不同耐盐性的二倍体马铃薯富利亚（Solanum phureja, PHU） 和窄刀薯假stenotomum,STN）杂种（PHU．STN）无性系为材料,在离体条件下用0（对照）、10、20、30mmol·L^-1NaCl进行胁迫处理,测定试管苗叶的电导率、丙二醛和脯氨酸含量,结果表明,随着盐浓度的升高,这3个生理指标的相对值均逐渐升高,耐盐性不同的二倍体马铃薯差异极显著。表明电导率、丙二醛和脯氨酸含量可以作为二倍体马铃薯耐盐性鉴定的生理指标。     

水稻非生物胁迫相关QTL研究进展

培育优质高产水稻品种是水稻育种工作者的首要目标。近年来,不断恶化的环境条件使水稻生长面,临更多的逆境胁迫。其中,非生物胁迫严重影响水稻产量提高和品质改善。从QTL角度研究水稻对非生物胁迫的适应机理,对于提高水稻产量、品质和抗逆性等方面具有重要的意义。本文综述了近年来水稻非生物胁迫相关QTL的研究进展,以及通过分子辅助育种手段创制多目标性状聚合的优良水稻品种的主要策略,为实现水稻优质高产和广适性的综合改良提供思路。     

PSCA gene variants (rs2294008 and rs2978974) confer increased susceptibility of gallbladder carcinoma in females

Background and aim

PSCA is a tissue specific tumor suppressor or oncogene which has been found to be associated with several human tumors including gallbladder cancer. It is considered to be involved in the cell-proliferation inhibition and/or cell-death induction activity. Therefore, we aimed to investigate the role of PSCA gene polymorphisms in gallbladder cancer risk in North Indian population.

Methodology

A total of 405 gallbladder cancer patients and 247 healthy controls were included in the case–control study for risk prediction. We examined the association of two functional SNPs, rs2294008 and rs2978974 in PSCA gene by genotyping using Taqman allelic discrimination assays. Statistical analysis was done using SPSS software, version 17. Linkage disequilibrium and haplotype analysis was done with the help of SNPstats software. FDR test was used to correct for multiple comparisons.

Results

No significant associations of rs2294008 and rs2978974 genetic variants of the PSCA gene were found with GBC risk at allele, genotype or haplotype levels. Stratifying the subjects on the basis of gallstone also did not show any significant result. However, on gender stratification, we found a significant association of T_rs2294008-G_rs2978974 haplotype with higher risk of GBC in females (FDR Pcorr = 0.021, OR = 1.6). In contrary, T_rs2294008-A _rs2978974 haplotype conferred significant lower risk in males (FDR Pcorr = 0.013; OR = 0.25).

Conclusions

These findings suggest that PSCA genetic variants may have a significant effect on GBC susceptibility in a gender specific manner.     

水稻Rop基因OsRac5表达特性

Rop在植物生长、发育、免疫及环境信号应答等多种生物学过程中具有重要作用。已有研究显示水稻Rop基因OsRac5可能与育性控制有关,但是该基因的表达特性,以及非生物胁迫和植物生长物质对其表达的影响尚不清楚。本文采用qRT-PCR技术检测了OsRac5在水稻生长发育过程中、非生物胁迫以及植物生长物质处理条件下的表达特性,结果显示OsRac5在水稻生长发育过程中在多种组织广泛表达,尤其在根和雌雄蕊形成期的幼穗中高表达;干旱、高盐和低温等非生物胁迫均能诱导OsRac5表达;ABA、GAs、6-BA等植物生长物质能上调OsRac5基因表达,提示该基因与水稻幼穗发育、抗逆性及细胞生长等过程相关。     

Inactivation of Pseudomonas aeruginosa biofilms formed under high shear stress on various hydrophilic and hydrophobic surfaces by a continuous flow of ozonated water

Abstract

The inactivation of Pseudomonas aeruginosa biofilms grown on glass under high shear stress and exposed to a range of dissolved ozone concentrations (2, 5 and 7?ppm) at 10 and 20?min was investigated. The regression equation, log reduction (biofilm)?=?0.64?+?0.59×(C – 2)?+?0.33×(T – 10), described the dependence of biofilm inactivation on the dissolved ozone concentration (C, ppm) and contact time (T, min). The predicted D-values were 11.1, 5.7 and 2.2?min at 2, 5 and 7?ppm, respectively. Inactivation of biofilms grown on various surfaces was tested at a single dissolved ozone concentration of 5?ppm and a single exposure time of 20?min. Biofilms grown on plastic materials showed inactivation results similar to that of biofilms on glass, while biofilms grown on ceramics were statistically significantly more difficult to inactivate, suggesting the importance of utilizing non-porous materials in industrial and clinical settings.     

Newspaper Portrayals,Local Policies,and Dog-Supportive Public Space: Who's Wagging Whom?

ABSTRACT

Dog-walking promotes physical activity and positive social interactions, and thus dog-walking has implications for people's physical and mental health. As a result, experts in public health have endorsed designing and managing public space to support dog-walking. Nevertheless, the presence of dogs in public space is subject to negotiation and can be controversial. Generally, municipal governments or local councils exercise political jurisdiction over both dogs and public space. As a case study, we systematically collected and analyzed a local newspaper's portrayals of issues relating to dog-walking in public space. Our purpose was to understand how public and policy agendas were being represented by local media, during a period of time when local policies on dog ownership and dog-supportive public space were being reviewed and revised. The analysis involved three phases: 1) thematic content analysis; 2) issue framing analysis; and 3) policy analysis. Thematically, we found that social conflict predominated. In terms of issue framing, local policy and individual dog owner behavior were both problematized. Over time, the policy agenda evolved to emphasize the design and management of public space, especially park land. Policy-makers presented this emphasis on public space as a proactive strategy to reduce social conflict and to promote compliance with existing rules on dog ownership. When it comes to promoting dog-walking to benefit animal welfare and human health, our findings underscore the importance of paying close attention to local policies and media coverage. In fact, we found that endogenous conflict and public controversies can actually represent significant opportunities to bring about positive changes in the lives of humans and nonhuman animals.     

The facilitation of social interactions by domestic dogs

Abstract

Research suggests that dogs can facilitate social interactions, which, in turn, may promote psychological health. This study explored the ability of dogs to facilitate social responses relative to other accompaniments and investigated whether the social catalysis effect is generic or influenced by the appearance of the dog. The behavior of 1800 pedestrians approaching a female experimenter was recorded as a function of the presence of three dogs (Labrador Retriever pup, Labrador adult, Rottweiler adult) and two neutral stimuli (teddy bear, potted plant). The behavior of pedestrians approaching the woman whenever she was alone (control) was also explored. Information was collected on the passers-by’ gender, number of people in the party, type of acknowledgement elicited and length of conversations. More people ignored the experimenter whenever she was alone or with the teddy or plant, than whenever she was walking a dog. The Rottweiler resulted in more nonresponses than the puppy or adult Labrador, who in turn elicited more smiles and verbal responses. Females, and those alone, elicited more smiles and conversations than males, or those in pairs. It is concluded that dogs can facilitate social interactions between adults better than other accompaniments; however, the social catalysis effect is not generic, but dog specific.