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991.
Qiuli Zhao Li Yang Xiao Zhang Xuemei Zhu Qingqing Zuo Yanni Wu Liu Yang Wei Gao Minghui Li Shanshan Cheng 《PloS one》2014,9(10)
Background and Purpose
Measures of specific knowledge of coping with pre-hospital stroke symptoms can help educate high-risk patients and family caregivers. This study aimed to develop and validate the Pre-hospital Stroke Symptoms Coping Test (PSSCT).Materials and Methods
Reliability and validity were analyzed using multiple data sources. The Delphi expert consultation method was applied to assess the test’s surface validity and content validity index. The final edition of the 19-item PSSCT contained 3 sections assessing coping with typical symptoms and symptoms associated with vomiting and twitching. Its psychometric properties were investigated in a community sample of 300 high-risk patients and family members.Results
The PSSCT was readily accepted by participants. It demonstrated adequate surface validity and content validity, and good internal consistency (KR20 = 0.822) and test-retest reliability (0.769), with difficulty (P) and degree of differentiation (D) ranges of 0.28–0.83 and 0.15–0.66, respectively. It was also able to distinguish between individuals who had/had not experienced a stroke. Experienced individuals scored significantly higher overall and on coping with typical symptoms and twitching (P<0.01).Conclusions
The PSSCT can practically and directly assess critical knowledge regarding coping with pre-hospital stroke symptoms and has good reliability and validity. 相似文献992.
Yanmei Jiang Changfu Zhang Kai Chen Zhe Chen Zhigang Sun Zhuqing Zhang Dongbing Ding Shuangyi Ren Yunfei Zuo 《PloS one》2014,9(12)
Background
Colon cancer has always been diagnosed at a late stage, which is associated with poor prognosis. The currently used serum tumor markers CEA and CA19-9 display low sensitivity and specificity and may not have diagnostic value in early stage colon cancer. Thus, there is an urgent need to identify novel serum biomarkers for use in the early detection of colon cancer.Methods
In this study, the expression of DC-SIGN and DC-SIGNR in serum was detected by enzyme-linked immunosorbent assay (ELISA). DC-SIGN and DC-SIGNR expression was detected in cancer tissues by immunohistochemistry (IHC).Results
The level of sDC-SIGN was lower in patients than in the healthy controls, while the level of sDC-SIGNR in patients was higher than in the healthy controls. Both sDC-SIGN and sDC-SIGNR had diagnostic significances for cancer patients, and the combined diagnosis of these two markers was higher than both of them alone. Furthermore, there were significant differences between both sDC-SIGN and sDC-SIGNR in stage I/II patients and the healthy controls. Moreover, high sDC-SIGN level was accompanied with the long survival time. Additionally, DC-SIGNR was negative in the cancer foci and matched normal colon tissues but was weakly positive between the cancer foci. DC-SIGN staining was faint in matched normal colon tissues, strong in the tumor stroma and the invasive margin of colon cancer tissues, and negatively correlated with the sDC-SIGN level in serum from the same patient. Interestingly, the percent survival of patients with a DC-SIGN mean density of>0.001219 (the upper 95% confidence interval of matched normal colon tissues) was higher than for all other patients.Conclusion
DC-SIGN and DC-SIGNR are blood-based molecular markers that can potentially be used for the diagnosis of early stage patients. Moreover, expression of DC-SIGN in serum and cancer tissues may affect the survival time for colon cancer patients. 相似文献993.
Guo X Pace RG Stonebraker JR Commander CW Dang AT Drumm ML Harris A Zou F Swallow DM Wright FA O'Neal WK Knowles MR 《PloS one》2011,6(10):e25452
Variability in cystic fibrosis (CF) lung disease is partially due to non-CFTR genetic modifiers. Mucin genes are very polymorphic, and mucins play a key role in the pathogenesis of CF lung disease; therefore, mucin genes are strong candidates as genetic modifiers. DNA from CF patients recruited for extremes of lung phenotype was analyzed by Southern blot or PCR to define variable number tandem repeat (VNTR) length polymorphisms for MUC1, MUC2, MUC5AC, and MUC7. VNTR length polymorphisms were tested for association with lung disease severity and for linkage disequilibrium (LD) with flanking single nucleotide polymorphisms (SNPs). No strong associations were found for MUC1, MUC2, or MUC7. A significant association was found between the overall distribution of MUC5AC VNTR length and CF lung disease severity (p = 0.025; n = 468 patients); plus, there was robust association of the specific 6.4 kb HinfI VNTR fragment with severity of lung disease (p = 6.2×10(-4) after Bonferroni correction). There was strong LD between MUC5AC VNTR length modes and flanking SNPs. The severity-associated 6.4 kb VNTR allele of MUC5AC was confirmed to be genetically distinct from the 6.3 kb allele, as it showed significantly stronger association with nearby SNPs. These data provide detailed respiratory mucin gene VNTR allele distributions in CF patients. Our data also show a novel link between the MUC5AC 6.4 kb VNTR allele and severity of CF lung disease. The LD pattern with surrounding SNPs suggests that the 6.4 kb allele contains, or is linked to, important functional genetic variation. 相似文献
994.
Jingzhe Zhang Guangyao Liu Qiong Wu Jianlin Zuo Yanguo Qin Jincheng Wang 《仿生工程学报(英文版)》2012,9(2):243-251
The objective of the present investigation was to evaluate the osteogenic properties of mesoporous Hydroxyapatite/Chitosan (HA/CS) composite in vitro and in vivo.HA/CS composite was successfully prepared and synthesized using a freeze-drying method,and then characterized by Scanning Electron Microscope (SEM).Results show that the mesoporous HA/CS composite presents high surface area and porosity.The effects of mesoporous HA/CS on early adhesion,proliferation and differentiation of osteoblast cells in vitro were measured.MTT cytotoxicity test and cell adhesion test show that the composite has good biocompatibility and promotes cell viability and proliferation.In vitro tests show that osteoblast-like cells on the composite surfaces are able to adhere,proliferate,and migrate through the pores.These cells maintained similar expression levels of osteoblastic-associated markers namely Collagen type Ⅰ (COL-I),Bone Morphogenetic Protein 2(BMP-2).Histologic analysis and radiological analysis in vivo also prove that mesoporous HA/CS composite can be used to repair bone defect as a new kind of bone grafting materials. 相似文献
995.
996.
Fan Q Yan X Wang J Chen Y Wang X Li C Tan L You C Zhang T Zuo S Xu D Chen K Finlayson-Burden JM Xiao Z 《PloS one》2012,7(4):e35889
Background
Abnormalities of myelin integrity have been reported in obsessive-compulsive disorder (OCD) using multi-parameter maps of diffusion tensor imaging (DTI). However, it was still unknown to what degree these abnormalities might be affected by pharmacological treatment.Objective
To investigate whether the abnormalities of white matter microstructure including myelin integrity exist in OCD and whether they are affected by medication.Methodology and Principal Findings
Parameter maps of DTI, including fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD), were acquired from 27 unmedicated OCD patients (including 13 drug-naïve individuals) and 23 healthy controls. Voxel-based analysis was then performed to detect regions with significant group difference. We compared the DTI-derived parameters of 15 patients before and after 12-week Selective Serotonin Reuptake Inhibitor (SSRI) therapies. Significant differences of DTI-derived parameters were observed between OCD and healthy groups in multiple structures, mainly within the fronto-striato-thalamo-cortical loop. An increased RD in combination with no change in AD among OCD patients was found in the left medial superior frontal gyrus, temporo-parietal lobe, occipital lobe, striatum, insula and right midbrain. There was no statistical difference in DTI-derived parameters between drug-naive and previously medicated OCD patients. After being medicated, OCD patients showed a reduction in RD of the left striatum and right midbrain, and in MD of the right midbrain.Conclusion
Our preliminary findings suggest that abnormalities of white matter microstructure, particularly in terms of myelin integrity, are primari ly located within the fronto-striato-thalamo-cortical circuit of individuals with OCD. Some abnormalities may be partly reversed by SSRI treatment. 相似文献997.
Yuan Y Zhang X Huang S Zuo L Zhang G Song Y Wang G Wang H Huang D Han D Dai P 《PloS one》2012,7(2):e30720
Background
Thirty thousand infants are born every year with congenital hearing impairment in mainland China. Racial and regional factors are important in clinical diagnosis of genetic deafness. However, molecular etiology of hearing impairment in the Tibetan Chinese population living in the Tibetan Plateau has not been investigated. To provide appropriate genetic testing and counseling to Tibetan families, we investigated molecular etiology of nonsyndromic deafness in this population.Methods
A total of 114 unrelated deaf Tibetan children from the Tibet Autonomous Region were enrolled. Five prominent deafness-related genes, GJB2, SLC26A4, GJB6, POU3F4, and mtDNA 12S rRNA, were analyzed. Inner ear development was evaluated by temporal CT. A total of 106 Tibetan hearing normal individuals were included as genetic controls. For radiological comparison, 120 patients, mainly of Han ethnicity, with sensorineural hearing loss were analyzed by temporal CT.Results
None of the Tibetan patients carried diallelic GJB2 or SLC26A4 mutations. Two patients with a history of aminoglycoside usage carried homogeneous mtDNA 12S rRNA A1555G mutation. Two controls were homozygous for 12S rRNA A1555G. There were no mutations in GJB6 or POU3F4. A diagnosis of inner ear malformation was made in 20.18% of the Tibetan patients and 21.67% of the Han deaf group. Enlarged vestibular aqueduct, the most common inner ear deformity, was not found in theTibetan patients, but was seen in 18.33% of the Han patients. Common molecular etiologies, GJB2 and SLC26A4 mutations, were rare in the Tibetan Chinese deaf population.Conclusion
The mutation spectrum of hearing loss differs significantly between Chinese Tibetan patients and Han patients. The incidence of inner ear malformation in Tibetans is almost as high as that in Han deaf patients, but the types of malformation vary greatly. Hypoxia and special environment in plateau may be one cause of developmental inner ear deformity in this population. 相似文献998.
蛋白酶抑制剂可以增强植物对病虫害的抵抗能力,为了深入研究蛋白酶抑制剂在烟草中的作用机制,利用生物信息学的方法,成功获得了烟草品种K326中的4种蛋白酶抑制剂cDNA序列(NtPI-1、NtPI-2、NtPI-3和NtPI-4)并对其进行了序列分析.它们编码的氨基酸序列都具有典型的马铃薯蛋白酶抑制剂Ⅰ家族功能结构域,属于马铃薯蛋白酶抑制剂Ⅰ家族成员.序列分析表明,4种蛋白酶抑制剂基因cDNA序列均具有完整的开放读码框,依次编码128、95、94和72个氨基酸残基,它们的氨基酸序列一致性在31%-38%之间.系统树分析表明,烟草品种K326中的4种蛋白酶抑制剂分散在进化树的不同位置,形成不同亚群. 相似文献
999.
Juan Wang Wen-Yuan Gao Jian Zhang Bei-Mei Zuo Li-Ming Zhang Lu-Qi Huang 《Acta Physiologiae Plantarum》2012,34(2):397-403
Panax ginseng C. A. Meyer is one of the important nutraceutical and medicinal plants, which is used worldwide. Until now, ginseng has been
reported to contain saponins, antioxidants, peptides, polysaccharides, fatty acids, vitamins, alkaloids, lignans, and flavonoids.
The saponins, known as ginsenosides, are widely believed to be the major bioactive compounds of ginseng. In this article,
ginsenoside biosynthesis pathway and key enzymes regulation are also described. This review provides a reference for improving
ginsenoside contents through regulation of ginsenoside biosynthesis pathway. 相似文献