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41.
Ben C Collins Ludovic CJ Gillet Lorenz C Blum Lin‐Yang Cheng Olga Vitek Jeppe Mouritsen Genevieve Lachance Tim D Spector Emmanouil T Dermitzakis Ruedi Aebersold 《Molecular systems biology》2015,11(2)
The degree and the origins of quantitative variability of most human plasma proteins are largely unknown. Because the twin study design provides a natural opportunity to estimate the relative contribution of heritability and environment to different traits in human population, we applied here the highly accurate and reproducible SWATH mass spectrometry technique to quantify 1,904 peptides defining 342 unique plasma proteins in 232 plasma samples collected longitudinally from pairs of monozygotic and dizygotic twins at intervals of 2–7 years, and proportioned the observed total quantitative variability to its root causes, genes, and environmental and longitudinal factors. The data indicate that different proteins show vastly different patterns of abundance variability among humans and that genetic control and longitudinal variation affect protein levels and biological processes to different degrees. The data further strongly suggest that the plasma concentrations of clinical biomarkers need to be calibrated against genetic and temporal factors. Moreover, we identified 13 cis‐SNPs significantly influencing the level of specific plasma proteins. These results therefore have immediate implications for the effective design of blood‐based biomarker studies. 相似文献
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44.
Lawrence A. Palinkas Claudia V. Chavarin Claudia M. Rafful Mee Young Um Doroteo V. Mendoza Hugo Staines Gregory A. Aarons Thomas L. Patterson 《PloS one》2015,10(10)
Objective
This study examined service provider perceptions of requirements for successful sustainment of an efficacious intervention for preventing HIV/AIDS and STIs in female sex workers (FSWs) in Mexico.Methods
Semi-structured interviews were conducted with 77 leaders and counselors from 12 community-based reproductive health clinics located throughout Mexico participating in a large hybrid effectiveness-implementation randomized controlled trial to scale-up the use of Mujer Segura, a psychoeducational intervention designed to promote condom use and enhance safer sex negotiation skills among FSWs.Results
Five sets of requirements for sustainment were identified: 1) characteristics of the provider, including competence in delivering the intervention, need for continued technical support and assistance from outside experts, and satisfaction with addressing the needs of this population; 2) characteristics of the clients (i.e., FSWs), including client need and demand for services and incentives for participation; 3) characteristics of the organization, including its mission, benefits, and operations; 4) characteristics of the outer setting, including financial support and relationship with the community-based organization’s central offices, and transportation and security in areas where FSWs live and work; and 5) outcomes associated with the intervention itself, including a reduction of risk through education and increased outreach through referrals from FSWs who received the intervention.Conclusions
Although the requirements for successful sustainment of interventions like Mujer Segura are consistent with the factors identified in many models of implementation, the results illustrate the importance of local context in assigning priority to these model elements and suggest that the five categories are not discrete entities but interconnected. 相似文献45.
46.
Ting Hway Wong Hai V. Nguyen Ming Terk Chiu Khuan Yew Chow Marcus Eng Hock Ong Gek Hsiang Lim Nivedita Vikas Nadkarni Dianne Carrol Tan Bautista Jolene Yu Xuan Cheng Lynette Mee Ann Loo Dennis Chuen Chai Seow 《PloS one》2015,10(9)
Background
Frailty is associated with adverse outcomes including disability, mortality and risk of falls. Trauma registries capture a broad range of injuries. However, frail patients who fall comprise a large proportion of the injuries occurring in ageing populations and are likely to have different outcomes compared to non-frail injured patients. The effect of frail fallers on mortality is under-explored but potentially significant. Currently, many trauma registries define low falls as less than three metres, a height that is likely to include non-frailty falls. We hypothesized that the low fall from less than 0.5 metres, including same-level falls, is a surrogate marker of frailty and predicts long-term mortality in older trauma patients.Methods
Using data from the Singapore National Trauma Registry, 2011–2013, matched till September 2014 to the death registry, we analysed adults aged over 45 admitted via the emergency department in public hospitals sustaining blunt injuries with an injury severity score (ISS) of 9 or more, excluding isolated hip fractures from same-level falls in the over 65. Patients injured by a low fall were compared to patients injured by high fall and other blunt mechanisms. Logistic regression was used to analyze 12-month mortality, controlling for mechanism of injury, ISS, revised trauma score (RTS), co-morbidities, gender, age and age-gender interaction. Different low fall height definitions, adjusting for injury regions, and analyzing the entire adult cohort were used in sensitivity analyses and did not change our findings.Results
Of the 8111 adults in our cohort, patients who suffered low falls were more likely to die of causes unrelated to their injuries (p<0.001), compared to other blunt trauma and higher fall heights. They were at higher risk of 12-month mortality (OR 1.75, 95% CI 1.18–2.58, p = 0.005), independent of ISS, RTS, age, gender, age-gender interaction and co-morbidities. Falls that were higher than 0.5m did not show this pattern. Males were at higher risk of mortality after low falls. The effect of age on mortality started at age 55 for males, and age 70 for females, and the difference was attributable to the additional mortality in male low-fallers.Conclusions
The low fall mechanism can optimize prediction of long-term mortality after moderate and severe injury, and may be a surrogate marker of frailty, complementing broader-based studies on aging. 相似文献47.
Jin Il Kim Min-Woong Hwang Ilseob Lee Sehee Park Sangmoo Lee Joon-Yong Bae Jun Heo Donghwan Kim Seok-Il Jang Mee Sook Park Hyung-Joo Kwon Jin-Won Song Man-Seong Park 《Biochemical and biophysical research communications》2014
By nature of their segmented RNA genome, influenza A viruses (IAVs) have the potential to generate variants through a reassortment process. The influenza nonstructural (NS) gene is critical for a virus to counteract the antiviral responses of the host. Therefore, a newly acquired NS segment potentially determines the replication efficiency of the reassortant virus in a range of different hosts. In addition, the C-terminal PDZ-binding motif (PBM) has been suggested as a pathogenic determinant of IAVs. To gauge the pandemic potential from human and avian IAV reassortment, we assessed the replication properties of NS-reassorted viruses in cultured cells and in the lungs of mice and determined their transmissibility in guinea pigs. Compared with the recombinant A/Korea/01/2009 virus (rK09; 2009 pandemic H1N1 strain), the rK09/VN:NS virus, in which the NS gene was adopted from the A/Vietnam/1203/2004 virus (a human isolate of the highly pathogenic avian influenza H5N1 virus strains), exhibited attenuated virulence and reduced transmissibility. However, the rK09/VN:NS-PBM virus, harboring the PBM in the C-terminus of the NS1 protein, recovered the attenuated virulence of the rK09/VN:NS virus. In a guinea pig model, the rK09/VN:NS-PBM virus showed even greater transmission efficiency than the rK/09 virus. These results suggest that the PBM in the NS1 protein may determine viral persistence in the human and avian IAV interface. 相似文献
48.
Jung Min Song Kiwoong Nam Young-Uk Sun Mee Hye Kang Choong-Gon Kim Suk-Tae Kwon Jehee Lee Youn-Ho Lee 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2010,155(4):403-412
Collembolan species have been known to have β-1,3-glucanase activity and yet the genes coding such enzymes have not been demonstrated. We report here a novel arthropod endo-β-1,3-glucanase gene CaLam from the Antarctic springtail, Cryptopygus antarcticus. The open reading frame consists of 813 bp encoding 270 amino acids with a putative signal peptide and a typical motif of glycosyl hydrolase family 16 (GHF16), E–I–D–I–T–E. The recombinant protein expressed in E. coli shows the hydrolytic activity toward laminarin (Km ~ 9.98 mg/mL) with an optimal temperature 50 °C and an optimal pH 6.0. CaLam digests laminarin and laminarioligosaccharides except laminaribiose as an endo-β-1,3-glucanase, releasing glucose, laminaribiose and laminaritriose as the major products. Analyses of molecular phylogeny of CaLam and its protein structure reveal that CaLam is closely related with bacterial β-1,3-glucanases more than with the eukaryotic homologues. Even so, the genomic structure of the CaLam gene consisting of six exons interspersed with approximately 57 to 63 bp introns confirms that it is endogenous in the genome of the Antarctic springtail. These results suggest that CaLam should have been transferred from bacteria to the lineage of the Collembolan species by horizontal gene transfer. 相似文献
49.
Mee‐Sun Hyun Jung‐Mu Hur Yeun‐Ja Mun Dongho Kim Won‐Hong Woo 《Journal of cellular biochemistry》2010,109(2):329-338
Berberine (BBR) has indicated significant antimicrobial activity against a variety of organisms including bacteria, viruses, and fungi. The mechanism by which BBR initiates apoptosis remains poorly understood. In the present study, we demonstrated that BBR exhibited significant cytotoxicity in human hepatoma HepG2 cells. Herein, we investigated cytotoxicity mechanism of BBR in HepG2 cells. The results showed that the induction of apoptosis in HepG2 cells by BBR was characterized by DNA fragmentation, an increased percentage of annexin V, and the activation of caspase‐3. The expressions of Bcl‐2 protein and pro‐caspase‐3 were reduced by BBR in HepG2 cells. However, Bax protein was increased in the cells. BBR‐induced apoptosis was preceded by increased generation of reactive oxygen species (ROS). NAC treatment, a scavenger of ROS, reversed BBR‐induced apoptosis effects via inhibition of Bax activation and Bcl‐2 inactivation. BBR‐induced, dose‐dependent induction of apoptosis was accompanied by sustained phosphorylation of MAP Kinases (JNK and p38 MAPK), ASK1, Akt, and p53. Furthermore, SB203580, p38 inhibitor, reduced the apoptotic effect of BBR, and blocks the generation of ROS and NO as well as activation of Bax. We found that the treatment of HepG2 cells with BBR triggers generation of ROS through Akt phosphorylation, resulting in dissociation of the ASK1‐mediated activation of JNK and p38 pathways. J. Cell. Biochem. 109: 329–338, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
50.
Dong-Hee Kim Hyun-Mi Son Joo Young Kim Min Kyoung Cho Mee Kyung Park Sin Ye Kang Bo Young Kim Hak Sun Yu 《The Korean journal of parasitology》2010,48(2):121-126
To know the prevalence of Enterobius vermicularis infection and what are the most important risk factors, we evaluated the incidence and risk factors of enterobiasis among children attended in kindergartens in Busan metropolitan city, Republic of Korea. A total of 1,674 children from 21 kindergartens in 11 of 16 autonomous districts of Busan were evaluated for E. vermicularis infection by the cellotape anal swab technique. The overall egg-positive rate for E. vermicularis was 10.7% (179/1,674), and the prevalence of enterobiasis in each kindergarten ranged between 0% and 32.4%. There was an increasing tendency of the egg positive rate according to the population density; the higher the population density communities had, the higher egg-positive rate for E. vermicularis was detected (P = 0.001). Among personal hygiene factors involving children, thumb-sucking (P = 0.036) and fingernail-trimming (P = 0.024) were highly associated with enterobiasis. In addition, taking anthelmintic medications against E. vermicularis infection was strongly associated with enterobiasis (P = 0.014). Moreover, parents'' knowledge of enterobiasis was correlated significantly with the incidence of enterobiasis of their children (P = 0.006). In conclusion, we need to consider not only personal hygiene but also parents'' knowledge about enterobiasis as a factor in order to develop new strategies for elimination or to complete reduction of enterobiasis in Korea. 相似文献