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111.
Background
The relationship between a number of primary sleep disorders and Parkinson''s disease (PD) is still debated. There are limited case control polysomnographic studies in PD and most of these study sample sizes are small.Methodology/Findings
We conducted one of the largest case-control studies involving overnight polysomnographic evaluation, with prospective recruitment of unselected Parkinson''s disease patients and healthy controls from an Asian population. The cases were recruited from the specialized movement disorder outpatient clinics in a tertiary referral center, and controls from the same geographical locations. All subjects underwent an overnight polysomnographic study and a multiple sleep latency test.A total of 124 subjects including 56 patients and 68 controls frequency-matched for age and sex were included. Multivariate analysis revealed that patients had significantly shorter total sleep time than controls (p = 0.01), lower sleep efficiency (p = 0.001) and increased REM latency (p = 0.007). In patients, multivariate analysis showed that reduced total sleep time was significantly associated with increased age (p = 0.001) and increased levodopa dose (p = 0.032). The mean Insomnia Severity Index was higher in PD patients (9.0±7.1) compared to controls (3.3±3.9, p<0.001). The mean Epworth Sleepiness Scale score was higher in PD patients (9.3±5.9 vs. 5.7±4.8, p<0.001). Nocturnal arousals, obstructive sleep apnea, periodic leg movements and objective abnormal sleepiness were not increased in our patients.Conclusions/Significance
Our case-control polysomnographic study, the first-ever performed in an Asian population, revealed altered sleep architecture and reduced sleep in PD patients compared to controls. Reduced total sleep time was associated with increased age and levodopa dose. However, nocturnal arousals, primary sleep disorders and abnormal sleepiness were not increased in our PD patients suggesting that ethnic/genetic differences may be a factor in the pathophysiology of these conditions. 相似文献112.
Liu S Shiotani B Lahiri M Maréchal A Tse A Leung CC Glover JN Yang XH Zou L 《Molecular cell》2011,43(2):192-202
The ataxia telangiectasia-mutated and Rad3-related (ATR) kinase is a master checkpoint regulator safeguarding the genome. Upon DNA damage, the ATR-ATRIP complex is recruited to sites of DNA damage by RPA-coated single-stranded DNA and activated by an elusive process. Here, we show that ATR is transformed into a hyperphosphorylated state after DNA damage, and that a single autophosphorylation event at Thr 1989 is crucial for ATR activation. Phosphorylation of Thr 1989 relies on RPA, ATRIP, and ATR kinase activity, but unexpectedly not on the ATR stimulator TopBP1. Recruitment of ATR-ATRIP to RPA-ssDNA leads to congregation of ATR-ATRIP complexes and promotes Thr 1989 phosphorylation in trans. Phosphorylated Thr 1989 is directly recognized by TopBP1 via the BRCT domains 7 and 8, enabling TopBP1 to engage ATR-ATRIP, to stimulate the ATR kinase, and to facilitate ATR substrate recognition. Thus, ATR autophosphorylation on RPA-ssDNA is a molecular switch to launch robust checkpoint response. 相似文献
113.
W Zou R Mackenzie L Thérien T Hirama Q Yang M A Gidney H J Jennings 《Journal of immunology (Baltimore, Md. : 1950)》1999,163(2):820-825
The protective epitope of the type III group B streptococcal polysaccharide (GBSPIII) is length dependent and conformational. To obtain a more accurate characterization of the conformational epitope, ELISA inhibition and surface plasmon resonance studies were conducted on two GBSPIII-specific mAbs using a large panel of oligosaccharide probes. The results of the studies confirmed that 2 repeating units (RU) is the minimum binding unit and that, while increases in chain length from 2 RU to 7 RU caused further optimization of the epitope, it remained monovalent. A 3-fold increase in affinity was observed between 7 RU and 20 RU, which, by surface plasmon resonance studies on a Fab, was shown to be due to both further optimization of the individual epitope and the occurrence of multivalency of epitope. The data support our hypothesis that the conformational epitope is an extended helical segment of the GBSPIII. GBSPIII exists mainly in the random coil form, which structurally mimics short oligosaccharide self Ags, but it can infrequently and spontaneously form extended helices. Although not prevalent in GBSPIII, the immune system preferentially selects these helical epitopes because they are unique to the polysaccharide. Contrary to a previously proposed model of GBSPIII binding in which the binding of the first Ab propagates a continuum of helical epitopes, our binding kinetics are consistent only with the helical epitope's being discontinuous and infrequent. 相似文献
114.
Molecular tagging and mapping of the erect panicle gene in rice 总被引:6,自引:0,他引:6
Fan Na Kong Jia Yu Wang Ji Cheng Zou Li Xue Shi Min De Jin Zheng Jin Xu Bin Wang 《Molecular breeding : new strategies in plant improvement》2007,19(4):297-304
Erect panicle (EP) is one of the more important traits of the proposed ideotype of high-yielding rice. Several rice cultivars
with the EP phenotype, which has been reported to be controlled by a dominant gene, have been successfully developed and released
for commercial production in North China. To analyze the inheritance of the EP trait, we generated segregating F2 and BC1F1 populations by crossing an EP-type variety, Liaojing 5, and a curved-panicle-type variety, Fengjin. Our results confirmed that a dominant gene controls the EP trait. Simple-sequence repeat (SSR) and bulked segregant analyses
of the F2 population revealed that the EP gene is located on chromosome 9, between two newly developed SSR markers, RM5833-11 and RM5686-23, at a genetic distance
of 1.5 and 0.9 cM, respectively. Markers closer to the EP gene were developed by amplified fragment length polymorphism (AFLP) analysis with 128 AFLP primer combinations. Three AFLP
markers were found to be linked to the EP gene, and the nearest marker, E-TA/M-CTC200, was mapped to the same location as SSR marker RM5686-23, 1.5 cM from the EP gene. A local map around the EP gene comprising nine SSR and one AFLP marker was constructed. These markers will be useful for marker-assisted selection
(MAS) for the EP trait in rice breeding programs. 相似文献
115.
116.
Objectives
China is facing the unprecedented challenge of rapidly increasing rural-to-urban migration. Migrants are in a vulnerable state when they attempt to access to primary care services. This study was designed to explore rural-to-urban migrants’ experiences in primary care, comparing their quality of primary care experiences under different types of medical institutions in Guangzhou, China.Methods
The study employed a cross-sectional survey of 736 rural-to-urban migrants in Guangzhou, China in 2014. A validated Chinese version of Primary Care Assessment Tool—Adult Short Version (PCAT-AS), representing 10 primary care domains was used to collect information on migrants’ quality of primary care experiences. These domains include first contact (utilization), first contact (accessibility), ongoing care, coordination (referrals), coordination (information systems), comprehensiveness (services available), comprehensiveness (services provided), family-centeredness, community orientation and culturally competent. These measures were used to assess the quality of primary care performance as reported from patients’ perspective. Analysis of covariance was conducted for comparison on PCAT scores among migrants accessing primary care in tertiary hospitals, municipal hospitals, community health centers/community health stations, and township health centers/rural health stations. Multiple linear regression models were used to explore factors associated with PCAT total scores.Results
After adjustments were made, migrants accessing primary care in tertiary hospitals (25.49) reported the highest PCAT total scores, followed by municipal hospitals (25.02), community health centers/community health stations (24.24), and township health centers/rural health stations (24.18). Tertiary hospital users reported significantly better performance in first contact (utilization), first contact (accessibility), coordination (information system), comprehensiveness (service available), and cultural competence. Community health center/community health station users reported significantly better experience in the community orientation domain. Township health center/rural health station users expressed significantly better experience in the ongoing care domain. There were no statistically significant differences across settings in the ongoing care, comprehensiveness (services provided), and family-centeredness domains. Multiple linear regression models showed that factors positively associated with higher PCAT total scores also included insurance covering parts of healthcare payment (P<0.001).Conclusions
This study highlights the need for improvement in primary care provided by primary care institutions for rural-to-urban migrants. Relevant policies related to medical insurance should be implemented for providing affordable healthcare services for migrants accessing primary care. 相似文献117.
118.
Yun-He Li Yong-Jie Wu Bei Wu Ming-Hong Zou Zhi Zhang Guang-Ming Sun 《Acta Physiologiae Plantarum》2011,33(5):1715-1722
In mainland China, the most popular pineapple cultivar is ‘Comte de Paris’. Gibberellic acids have been widely applied to
enhance fruit growth in various species. To evaluate the effect of gibberellic acid (GA3) on ‘Comte de Paris’ pineapple production and quality, pineapple fruits were sprayed with GA3 at concentrations of 5, 20, 50, or 100 mg l−1 at both 0 and 15 days after flowering (DAF). Fruits were sampled every 15 days from 0 to 60 DAF (maturation) for flow cytometric
analysis and histological observation. The results showed that the treatments with the three highest concentrations of GA3 significantly increased fruit weight, and the most effective concentration was 50 mg l−1 GA3, which increased the flesh weight by 20.3% compared to the control. Although treatment with GA3 had little effect on the total soluble solids and fruit juice pH, it increased the vitamin C content. Although flow cytometric
analysis showed that the 50 mg l−1 GA3 treatment had only a slight impact on the number of S phase cells, histological observations indicated that the increase
of fruit volume and flesh weight under this GA3 treatment was not due to the increase of cell number but a result of the increase of cell area in the fruit flesh. 相似文献
119.
Background
Hepatocellular carcinoma (HCC) is the third most common cause of cancer related mortality worldwide. 9-Nitrocamptothecin (9NC) is a potent topoisomerase-I inhibitor with strong anticancer effect. To increase the solubility and stability, we synthesized a novel 9NC loaded liposomes (9NC-LP) via incorporating 9NC into liposomes. In the present study, we determined the effects of 9NC and 9NC-LP on in vitro and in vivo, and the underlying mechanisms.Methodology/Principal Findings
We first analyzed the characteristics of 9NC-LP. Then we compared the effects of 9NC and 9NC-LP on the proliferation and apoptosis of HepG2, Bel-7402, Hep3B and L02 cells in vitro. We also investigated their anticancer properties in nude mice bearing HCC xenograft in vivo. 9NC-LP has a uniform size (around 190 nm) and zeta potential (∼−11 mV), and exhibited a steady sustained-release pattern profile in vitro. Both 9NC and 9NC-LP could cause cell cycle arrest and apoptosis in a dose-dependent and p53-dependent manner. However, this effect was not ubiquitous in all cell lines. Exposure to 9NC-LP led to increased expression of p53, p21, p27, Bax, caspase-3, caspase-8, caspase-9 and apoptosis-inducing factor, mitochondrion-associated 1 and decreased expression of Bcl-2, cyclin E, cyclin A, Cdk2 and cyclin D1. Furthermore, 9NC-LP exhibited a more potent antiproliferative effect and less side effects in vivo. Western blot analysis of the xenograft tumors in nude mice showed similar changes in protein expression in vivo.Conclusions/Significance
In conclusion, 9NC and 9NC-LP can inhibit HCC growth via cell cycle arrest and induction of apoptosis. 9NC-LP has a more potent anti-tumor effect and fewer side effects in vivo, which means it is a promising reagent for cancer therapy via intravenous administration. 相似文献120.
肉鸭发酵床抗生素、重金属累积及细菌耐药性的演变特性 总被引:2,自引:0,他引:2
【目的】了解肉鸭发酵床使用过程中抗生素、各类金属元素累积特性,细菌抗生素耐受性演变特性。【方法】2011年11月至2013年7月,江苏某肉鸭发酵床养殖场饲养肉鸭期间,选取刚制作完成发酵床的鸭舍,和饲养4批次、8批次肉鸭时的鸭舍,检测发酵床中抗生素、金属元素含量,及发酵床中细菌的抗生素耐受水平。【结果】肉鸭发酵床垫料内强力霉素残留量因每批次肉鸭饲料中的使用而显著上升,氧氟沙星未现在垫料内累积。发酵床垫料饲养至8批次肉鸭时,垫料内耐受16、100μg/m L强力霉素三种可培养细菌的平均菌落数与比例为最高,而耐受8、50μg/m L氧氟沙星的平均菌落数、菌落数比例未现明显的增长趋势。发酵床使用过程中,垫料内As、Pb、Hg元素含量未显著增加,Cd元素检测量极低,Zn、Mn元素含量增加趋势明显,Cu、Cr元素累积速度缓慢。【结论】每批次使用强力霉素可在多批次肉鸭饲养后显著增加发酵床垫料中强力霉素含量,显著增强垫料中肠道菌群耐受强力霉素能力,Zn、Mn元素含量总体呈上升趋势。 相似文献