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51.

Background

From November 2011 to January 2012, a number of clustering cases of HCV infection were reported in Zijin County, Heyuan City, Guangdong, China. Most patients in the clustering cases suspected that they could be infected due to inappropriate medical care in the clinic located at the Xiangshui road. However, the molecular epidemiology of the clustering cases remains unknown.

Methodology

The residents, living at Xiangshui Road, with HCV antibody positive reported from 2011 and 2012 were recruited. A survey of the HCV infected individuals from the clustering cases was conducted. Each participant underwent a questionnaire defining demographic characteristics and health care history. HCV serological test and viral load test were performed to confirm the infection status. Molecular phylogenetic analysis and Bayesian coalescence analysis were conducted to further confirm the HCV subtype distribution and to reconstruct the associated demographic history and time-scaled phylogeny among the clustering cases.

Principal Findings

The molecular phylogenetic analysis revealed that only two HCV subtypes, 2a and 6a, were found among the clustering cases. There was no close HCV subtype evolutionary relation was observed among patients from the same family. The 6a cluster showed higher viral loads than the 2a cluster. In addition, the Bayesian skyline plot analysis showed that both the HCV 2a and 6a subtype infections among the Heyuan cases experienced an “expansion-diminishment-expansion” featured dissemination. The 2a clustering infection occurred in 2004, and the 6a clustering cases originated in 2006.

Conclusions

The molecular epidemiological characters imply that the inappropriate medical practices were possibly associated with the clustering HCV cases in Heyuan City during 2011, 2012. Latent HCV subtypes 2a and 6a infection may cause the prevalence and become a new public health issue in Guangdong, China.  相似文献   
52.

Background

To examine the characteristics of oxidative stress in patients with acute kidney injury (AKI) and investigate the association between plasma nitrotyrosine levels and 90-day mortality in patients with AKI.

Methodology/Principal Findings

158 patients with hospital-acquired AKI were recruited to this prospective cohort study according to RIFLE (Risk, Injury, Failure, Lost or End Stage Kidney) criteria. Twelve critically ill patients without AKI and 15 age and gender-matched healthy subjects served as control. Plasma 3-nitrotyrosine was analyzed in relation to 90-day all cause mortality of patients with AKI. The patients with AKI were followed up for 90 days and grouped according to median plasma 3-nitrotyrosine concentrations. Highest 3-NT/Tyr was detected in patients with AKI compared with healthy subjects, and critically ill patients without AKI (ANOVA p<0.001). The 90-day survival curves of patients with high 3-NT/Tyr showed significant differences compared with the curves of individuals with low 3-NT/Tyr (p = 0.001 by log rank test). Multivariate analysis (Cox regression) revealed that 3-NT/Tyr (p = 0.025) was independently associated with mortality after adjustment for age, gender, sepsis and Acute Physiology and Chronic Health Evaluation (APACHE) II score.

Conclusions/Significance

There is excess plasma protein oxidation in patients with AKI, as evidenced by increased nitrotyrosine content. 3-NT/Tyr level was associated with mortality of AKI patients independent of the severity of illness.  相似文献   
53.
Prdm16 determines the bidirectional fate switch of skeletal muscle/brown adipose tissue (BAT) and regulates the thermogenic gene program of subcutaneous white adipose tissue (SAT) in mice. Here we show that miR-133a, a microRNA that is expressed in both BAT and SATs, directly targets the 3′ UTR of Prdm16. The expression of miR-133a dramatically decreases along the commitment and differentiation of brown preadipocytes, accompanied by the upregulation of Prdm16. Overexpression of miR-133a in BAT and SAT cells significantly inhibits, and conversely inhibition of miR-133a upregulates, Prdm16 and brown adipogenesis. More importantly, double knockout of miR-133a1 and miR-133a2 in mice leads to elevations of the brown and thermogenic gene programs in SAT. Even 75% deletion of miR-133a (a1−/−a2+/−) genes results in browning of SAT, manifested by the appearance of numerous multilocular UCP1-expressing adipocytes within SAT. Additionally, compared to wildtype mice, miR-133a1−/−a2+/− mice exhibit increased insulin sensitivity and glucose tolerance, and activate the thermogenic gene program more robustly upon cold exposure. These results together elucidate a crucial role of miR-133a in the regulation of adipocyte browning in vivo.  相似文献   
54.
During development in the thymus, each T lymphocyte is equipped with one, essentially unique, T cell receptor (TCR)-specificity. Due to its random nature, this process inevitably also leads to the emergence of potentially dangerous T lymphocytes that may recognize ‘self.’ Nevertheless, autoimmune tissue destruction, the cause of diseases such as multiple sclerosis and diabetes, is the exception rather than the rule. This state of immunological self-tolerance is to a large degree based upon a process called ‘negative selection’: prior to joining the circulating lymphocyte pool, immature T cells test their receptor on self-antigens within the thymic microenvironment, and TCR engagement at this immature stage elicits an apoptotic suicide program. We now find evidence that macroautophagy supports the tolerogenic presentation of self-antigens in the thymus.  相似文献   
55.
DNA damage tolerance consisting of template switching and translesion synthesis is a major cellular mechanism in response to unrepaired DNA lesions during replication. The Rev1 pathway constitutes the major mechanism of translesion synthesis and base damage-induced mutagenesis in model cell systems. Rev1 is a dCMP transferase, but additionally plays non-catalytic functions in translesion synthesis. Using the yeast model system, we attempted to gain further insights into the non-catalytic functions of Rev1. Rev1 stably interacts with Rad5 (a central component of the template switching pathway) via the C-terminal region of Rev1 and the N-terminal region of Rad5. Supporting functional significance of this interaction, both the Rev1 pathway and Rad5 are required for translesion synthesis and mutagenesis of 1,N6-ethenoadenine. Furthermore, disrupting the Rev1–Rad5 interaction by mutating Rev1 did not affect its dCMP transferase, but led to inactivation of the Rev1 non-catalytic function in translesion synthesis of UV-induced DNA damage. Deletion analysis revealed that the C-terminal 21-amino acid sequence of Rev1 is uniquely required for its interaction with Rad5 and is essential for its non-catalytic function. Deletion analysis additionally implicated a C-terminal region of Rev1 in its negative regulation. These results show that a non-catalytic function of Rev1 in translesion synthesis and mutagenesis is mediated by its interaction with Rad5.  相似文献   
56.
Hydrophylita emporos n. sp. reared from eggs of Psolodesmus mandarinus mandarinus McLachlan (Zygoptera: Calopterygidae) in Taiwan is described. This is the first species of Hydrophylita to be described from the Old World, and the first record of phoresy in the genus. Adult females were observed aggregating at the base of the female damselfly’s abdomen. When the damselfly begins ovipositing, females move to the tip of the abdomen, enter the water and quickly locate eggs for parasitising. The article contains links to video footage of this process.  相似文献   
57.
Due to its accuracy, sensitivity and high throughput, real time quantitative PCR (RT-qPCR) has been widely used in analysing gene expression. The quality of data from such analyses is affected by the quality of reference genes used. Expression stabilities for nine candidate reference genes widely used in soybean were evaluated under different stresses in this study. Our results showed that EF1A and ACT11 were the best under salinity stress, TUB4, TUA5 and EF1A were the best under drought stress, ACT11 and UKN2 were the best under dark treatment, and EF1B and UKN2 were the best under virus infection. EF1B and UKN2 were the top two genes which can be reliably used in all of the stress conditions assessed.  相似文献   
58.
Radix Paeoniae Alba is widely used in Chinese traditional medicine to treat various diseases such as gastrointestinal disorders, immunomodulatory, cancer, and other diseases. In this paper, a novel acidic polysaccharide RPAPS purified from Radix Paeoniae Alba was evaluated for its structural features and potential of immunomodulatory and antioxidant activities. RPAPS (molecular weight: 1.0× 105 Da) was mainly composed of α-(1 → 4)-Glcp, α-Arap, α-Galp, α-Rhap, β-D-Glcp, α-(1 → 6)-linked Glcp and GalA. Immunological tests indicated that RPAPS could improve RAW264.7 phagocytic activity and LPS-induced splenocyte proliferation. For antioxidant activities, RPAPS showed reducing power and DPPH scavenging activity in dose dependent. Moreover, RPAPS could significantly protect the PC12 cells from H2O2 damage. These data implied polysaccharides RPAPS had the potential to be novel natural antioxidative and immunopotentiating agents for using in functional foods or medicine.  相似文献   
59.
Activin A belongs to the superfamily of transforming growth factor-β and plays an important role in hormone regulation and tissue development. However, few research studies have been conducted on the effect of activin A on feeding organs in fish. In this study, the zebrafish (Danio rerio) larvae were treated with 1 ng ml–1 activin A for 8 days continuously. The haematoxylin and eosin (H&E) staining section results revealed that the transverse inner diameter of the pharynx and oesophagus significantly increased on the third and eighth days after treatment compared with the control group (P < 0.05). On the eighth day, the cross-sectional area of the pharyngeal muscle increased by 8638 μm2 compared to the control group (P < 0.05). The RNA in situ hybridization results also showed that the expression of skeletal muscle-specific genes (myog and myod) was significantly increased in pharyngeal muscle on the eighth day. Furthermore, the qRT-PCR results showed the expression of gh gene was significantly increased on the eighth day (P < 0.05). At the same time, more larvae in activin A group were able to feed larger brine shrimp (Artemia) than in the control group on the eighth day. In conclusion, activin A could affect feeding by promoting the inner diameter and muscle development of the pharynx and oesophagus in zebrafish larvae. This study is the first to report that the development of the pharynx and oesophagus can directly affect food intake in fish larvae, which provides a theoretical basis for the study of food intake of fish at an early stage.  相似文献   
60.
Yin  Wenchao  Wang  Chunyan  Peng  Yue  Yuan  Wenlin  Zhang  Zhongjun  Liu  Hong  Xia  Zhengyuan  Ren  Congcai  Qian  Jinqiao 《Molecular biology reports》2020,47(5):3629-3639
Molecular Biology Reports - Oxidative stress induced necroptosis is important in myocardial ischemia/reperfusion injury. Dexmedetomidine (Dex), an α2-adrenoceptor (α2-AR) agonist, has...  相似文献   
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