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921.
922.
Wei Chen Wei Wang Beibei Zhu Hui Guo Yu Sun Jie Ming Na Shen Zhi Li Zhenling Wang Lifeng Liu Bingxi Cai Jiayu Duan Jiaoyuan Li Cheng Liu Rong Zhong Weiguo Hu Tao Huang Xiaoping Miao 《PloS one》2013,8(11)
Background
To investigate the association between rs1820453 which located in the promoter region of yes-associated protein 1 (YAP1) gene and breast cancer (BC) risk.Method and Findings
We conducted a hospital-based case-control study including a total of 480 BC cases and 545 cancer-free controls in Chinese population. Then the expression quantitative trait locus (e-QTL) analysis was performed to explore the possible function of rs1820453 to the YAP1 gene expression. The association between rs1820453 and BC risk was significantly identified with the odds ratio (OR) was 1.27 (95 % confidence interval (CI) =1.03-1.57) under allelic model when adjusted by age and menopausal status. In addition, the correlation analysis of rs1820453 and YAP1 expression level found that this variant was significantly associated with the gene expression in Chinese population. When compared with level of mRNA expression of the AA genotype (6.011±0.046), the mRNA expression level in CC genotype (5.903±0.026) was statistically lower (P=0.024).Conclusion
The results from this study suggested that rs1820453 A>C change may affect the gene expression and contribute to the risk of developing BC in Chinese population though larger sample-size studies along with functional experiments were anticipated to warrant the results. 相似文献923.
Sung-Min Kim Heejaung Kim Jeong-Seon Lee Kyung Seok Park Gye Sun Jeon Jeeheun Shon Suk-Won Ahn Seung Hyun Kim Kyung Min Lee Jung-Joon Sung Kwang-Woo Lee 《PloS one》2013,8(11)
Background
Patients with ALS may be exposed to variable degrees of chronic intermittent hypoxia. However, all previous experimental studies on the effects of hypoxia in ALS have only used a sustained hypoxia model and it is possible that chronic intermittent hypoxia exerts effects via a different molecular mechanism from that of sustained hypoxia. No study has yet shown that hypoxia (either chronic intermittent or sustained) can affect the loss of motor neurons or cognitive function in an in vivo model of ALS.Objective
To evaluate the effects of chronic intermittent hypoxia on motor and cognitive function in ALS mice.Methods
Sixteen ALS mice and 16 wild-type mice were divided into 2 groups and subjected to either chronic intermittent hypoxia or normoxia for 2 weeks. The effects of chronic intermittent hypoxia on ALS mice were evaluated using the rotarod, Y-maze, and wire-hanging tests. In addition, numbers of motor neurons in the ventral horn of the spinal cord were counted and western blot analyses were performed for markers of oxidative stress and inflammatory pathway activation.Results
Compared to ALS mice kept in normoxic conditions, ALS mice that experienced chronic intermittent hypoxia had poorer motor learning on the rotarod test, poorer spatial memory on the Y-maze test, shorter wire hanging time, and fewer motor neurons in the ventral spinal cord. Compared to ALS-normoxic and wild-type mice, ALS mice that experienced chronic intermittent hypoxia had higher levels of oxidative stress and inflammation.Conclusions
Chronic intermittent hypoxia can aggravate motor neuronal death, neuromuscular weakness, and probably cognitive dysfunction in ALS mice. The generation of oxidative stress with activation of inflammatory pathways may be associated with this mechanism. Our study will provide insight into the association of hypoxia with disease progression, and in turn, the rationale for an early non-invasive ventilation treatment in patients with ALS. 相似文献924.
Shyh-Ching Lo Guo-Chiuan Hung Bingjie Li Haiyan Lei Tianwei Li Kenjiro Nagamine Jing Zhang Shien Tsai Richard Bryant 《PloS one》2013,8(10)
Cultures previously set up for isolation of mycoplasmal agents from blood of patients with poorly-defined illnesses, although not yielding positive results, were cryopreserved because of suspicion of having low numbers of unknown microbes living in an inactive state in the broth. We re-initiated a set of 3 cultures for analysis of the "uncultivable" or poorly-grown microbes using NGS technology. Broth of cultures from 3 blood samples, submitted from OHSU between 2000 and 2004, were inoculated into culture flasks containing fresh modified SP4 medium and kept at room temperature (RT), 30°C and 35°C. The cultures showing evidence of microbial growth were expanded and subjected to DNA analysis by genomic sequencing using Illumina MiSeq. Two of the 3 re-initiated blood cultures kept at RT after 7–8 weeks showed evidence of microbial growth that gradually reached into a cell density with detectable turbidity. The microbes in the broth when streaked on SP4 agar plates produced microscopic colonies in ∼ 2 weeks. Genomic studies revealed that the microbes isolated from the 2 blood cultures were a novel Afipia species, tentatively named Afipia septicemium. Microbes in the 3rd culture (OHSU_III) kept at RT had a limited level of growth and could not reach a plateau with high cell density. Genomic sequencing identified the microbe in the culture as a previously unknown species of Bradyrhizobium bacteria. This study reports on the isolation of novel Afipia and Bradyrhizobium species. Isolation of Bradyrhizobium species bacteria has never been reported in humans. The study also reveals a previously unrecognized nature of hematogenous infections by the 2 unique groups of Bradyrhizobiaceae. Our studies show that improvement of culture system plus effective use of NGS technology can facilitate findings of infections by unusual microbes in patients having poorly-defined, sometimes mysterious illnesses. 相似文献
925.
Background
Previous meta-analyses that compared the outcome of SILC and CLC have not presented consistent conclusions. This meta-analysis was performed after adding many recent RCTs, to clarify this issue.Methods
Relevant articles published in English were identified by searching PubMed, Embase, Web of Knowledge, and the Cochrane Controlled Trial Register from January 1997 to February 2013. Reference lists of the retrieved articles were reviewed to identify additional articles. Primary outcomes (postoperative pain scores, cosmetic score, and length of incision) and secondary outcomes (operating time, blood loss, conversion rates, postoperative complications, postoperative hospital stay, time to initial oral intake, and time to resume work) were pooled. Quantitative variables were calculated using the weighted mean difference (WMD), and qualitative variables were pooled using odds ratios (OR).Results
25 appropriate RCTs were identified from 2128 published articles. 1841 patients were treated, 944 with SILC and 897 with CLC. SILC was superior to CLC in cosmetic score (WMD = 1.155, P<0.001), shorter length of incision (WMD = -3.285, P = 0.029), and postoperative pain within 12 h (VAS in 3-4 h, WMD = -0.704, P = 0.026; VAS in 6-8 h, WMD = -0.613, P = 0.010). CLC was superior to SILC in operating time (OT) (WMD = 13.613, P<0.001) and need of additional instruments (OR = 7.448, P<0.001). Other secondary outcomes were similar.Conclusions
SILC offered a better cosmetic result and less postoperative pain for patients with uncomplicated cholelithiasis or polypoid lesions of the gallbladder. However, SILC was associated with a longer OT and required additional instruments. 相似文献926.
Chuanzheng Sun Qiuli Li Zedong Hu Jiehua He Chao Li Guojun Li Xiaofeng Tao Ankui Yang 《PloS one》2013,8(11)
Background
Anaplastic thyroid carcinoma (ATC), a highly aggressive malignancy, has a poor prognosis, and the consensus on the most effective treatment is needed.Methods
Clinical data from all ATC patients treated in our institution over a 30-year period (between May 1980 and May 2010) were analyzed retrospectively with regard to mortality and survival rates (Kaplan–Meier). Multivariate analysis was performed using a Cox proportional hazards model.Results
Sixty cases were analyzed. The overall 1- and 3-year survival rates were 35.0% and 22.9%, respectively. Univariate analysis showed that the best prognosis was seen in patients younger than 55 years, those without distant metastases, those with white blood cell (WBC) counts < 10.0 × 109/L or blood platelet (PLT) counts < 300.0 × 109/L at presentation, those who did not receive chemotherapy, and those who received radiotherapy doses ≥ 40 Gy or underwent surgery plus postoperative radiotherapy. According to multivariate analysis, the WBC count at first presentation and the type of therapeutic regimen independently influenced survival.Conclusions
We found that the elevated peripheral PLT count may be an adverse prognostic factor of ATC patients. The prognosis for ATC is especially poor for patients with distant metastasis, a WBC count ≥ 10.0×109/L, a PLT count ≥ 300.0 × 109/L, or age ≥ 55 years. WBC count at presentation and surgery with or without postoperative radiotherapy independently influenced the prognosis. Intensive treatment combining surgery with postoperative radiotherapy is recommended for ATC patients with stage IVA/B disease. 相似文献927.
Activated persulfate oxidation technologies based on sulfate radicals were first evaluated for defluorination of aqueous perfluorooctanesulfonate (PFOS). The influences of catalytic method, time, pH and K2S2O8 amounts on PFOS defluorination were investigated. The intermediate products during PFOS defluorination were detected by using LC/MS/MS. The results showed that the S2O8
2− had weak effect on the defluorination of PFOS, while the PFOS was oxidatively defluorinated by sulfate radicals in water. The defluorination efficiency of PFOS under various treatment was followed the order: HT (hydrothermal)/K2S2O8 > UV (ultraviolet)/K2S2O8 > Fe2+/K2S2O8 > US (ultrasound)/K2S2O8. Low pH was favorable for the PFOS defluorination with sulfate radicals. Increase in the amount of S2O8
2− had positive effect on PFOS defluorination. However, further increase in amounts of S2O8
2− caused insignificant improvement in PFOS defluorination due to elimination of sulfate radicals under high concentration of S2O8
2−. CF3(CF2)nCOOH (n = 0–6) were detected as intermediates during PFOS defluorination. Sulfate radicals oxidation and hydrolysis were the main mechanisms involved in defluorination process of PFOS. 相似文献
928.
Tubificidae is often used in the wastewater treatment systems to minimize the sludge production because it can be fed on the activated sludge. The process conditions have effect on the growth, reproduction, and sludge reduction efficiency of Tubificidae. The effects of the water quality, density of worms, pH, temperature and dissolved oxygen (DO) concentration on the respiration rate of Tubificidae were investigated to determine the optimal conditions for the growth and metabolism of the worms and reveal the mechanisms involving the efficient sludge reduction in terms of these conditions. It was observed that the respiration rate was highest in the water discharged from an ecosystem that included symbiotic Tubificidae and microbes and was lowest in distilled water. Considering density of the worms, the highest rate was 81.72±5.12 mg O2/g(dry weight)·h·L with 0.25 g (wet weight) of worms in 1 L test flask. The maximum Tubificidae respiration rate was observed at a pH of 8.0±0.05, a rate that was more than twice as high as those observed at other pH values. The respiration rate increased in the temperature range of ∼8°C–22°C, whereas the rate declined in the temperature range of ∼22°C–30°C. The respiration rate of Tubificidae was very high for DO range of ∼3.5–4.5 mg/L, and the rates were relatively low for out of this DO range. The results of this study revealed the process conditions which influenced the growth, and reproduction of Tubificidae and sludge reduction at a microscopic level, which could be a theoretical basis for the cultivation and application of Tubificidae in wastewater treatment plants. 相似文献
929.
Yang Liu Qiliang Lai Chunming Dong Fengqin Sun Liping Wang Guangyu Li Zongze Shao 《PloS one》2013,8(11)
Bacteria closely related to Bacillus pumilus cannot be distinguished from such other species as B. safensis, B. stratosphericus, B. altitudinis and B. aerophilus simply by 16S rRNA gene sequence. In this report, 76 marine strains were subjected to phylogenetic analysis based on 7 housekeeping genes to understand the phylogeny and biogeography in comparison with other origins. A phylogenetic tree based on the 7 housekeeping genes concatenated in the order of gyrB-rpoB-pycA-pyrE-mutL-aroE-trpB was constructed and compared with trees based on the single genes. All these trees exhibited a similar topology structure with small variations. Our 79 strains were divided into 6 groups from A to F; Group A was the largest and contained 49 strains close to B. altitudinis. Additional two large groups were presented by B. safensis and B. pumilus respectively. Among the housekeeping genes, gyrB and pyrE showed comparatively better resolution power and may serve as molecular markers to distinguish these closely related strains. Furthermore, a recombinant phylogenetic tree based on the gyrB gene and containing 73 terrestrial and our isolates was constructed to detect the relationship between marine and other sources. The tree clearly showed that the bacteria of marine origin were clustered together in all the large groups. In contrast, the cluster belonging to B. safensis was mainly composed of bacteria of terrestrial origin. Interestingly, nearly all the marine isolates were at the top of the tree, indicating the possibility of the recent divergence of this bacterial group in marine environments. We conclude that B. altitudinis bacteria are the most widely spread of the B. pumilus group in marine environments. In summary, this report provides the first evidence regarding the systematic evolution of this bacterial group, and knowledge of their phylogenetic diversity will help in the understanding of their ecological role and distribution in marine environments. 相似文献
930.
Jatropha curcas L. is a highly drought and salt tolerant plant species that is typically used as a traditional folk medicine and biofuel crop in many countries. Understanding the molecular mechanisms that underlie the response to various abiotic environmental stimuli, especially to drought and salt stresses, in J. curcas could be important to crop improvement efforts. In this study, we cloned and characterized the gene for a late embryogenesis abundant (LEA) protein from J. curcas that we designated JcLEA. Sequence analyses showed that the JcLEA protein belongs to group 5, a subgroup of the LEA protein family. In young seedlings, expression of JcLEA is significantly induced by abscisic acid (ABA), dehydration, and salt stress. Subcellular localization analysis shows that that JcLEA protein is distributed in both the nucleus and cytoplasm. Moreover, based on growth status and physiological indices, the overexpression of JcLEA in transgenic Arabidopsis plants conferred increased resistance to both drought and salt stresses compared to the WT. Our data suggests that the group 5 JcLEA protein contributes to drought and salt stress tolerance in plants. Thus, JcLEA is a potential candidate gene for plant genetic modification. 相似文献