1.Statistical properties of nucleotide clusters in DNA sequences
Journal of Zhejiang University. Science. B 2005;6B(5):408-412
Using the complete genome of Plasmodiumfalciparum 3D7 which has 14 chromosomes as an example, we have examined the distribution functions for the amount of C or G and A or T consecutively and non-overlapping blocks of m bases in this system. The function P(S) about the number of the consecutive C-G or A-T content cluster conforms to the relation P(S)oce-as;values of the scaling exponent αCG are much larger than αAT; and αAT of 14 chromosomes are hardly changed, whereas αCG of 14chromosomes have a number of fluctuations. We found maximum value of A-T cluster size is much larger than C-G, which implies the existence of large A-T cluster. Our study of the width function ξ(m) of cluster C-G content showed that follows good power law ξ(m)ocm-γ. The average γ for 14 chromosomes is 0.931. These investigations provide some insight into the nucleotide clusters of DNA sequences, and help us understand other properties of DNA sequences.
4.Current situation and requirements of quality control of blood disease laboratory in Chongqing:a cross sectional study
Jingkang XIONG ; Xi ZHANG ; Cheng ZHANG ; Xiangui PENG ; Jiashun REN
Chongqing Medicine 2016;45(30):4271-4273
Objective To understand the current situation and requirements of laboratory quality control of blood diseases in Chongqing .Methods A self‐designed questionnaire was designed ,and the investigation was carried out in 60 hospitals of Chongqing district .The main contents of the investigation were related to the instruments of work environment ,the regulations ,the conditions of the personnel ,etc .Results A total of 60 questionnaires were distributed ,57 questionnaires were valid .In the study ,only 14 .04%laboratories were the blood disease specialist laboratory ,most hospitals could complete the basic inspection items .66 .67% hospitals had all the experimental procedures and SOP documents .Most of staffs were with intermediate professional titles and undergraduate education .A total of 35 .08% experimental equipments with the value of over 5 million RMB ,45 .61% equipments had a special in‐spection records .About 45 .61% test reports would refer to the clinical performance ,and had a strict signing guideline .Most of the research objects reflected the problems ,including the backward equipments and the lack of personnel ,and hoped to set up telemedi‐cine indemnity system and carry out further education .Conclusion The overall quality of the laboratory for blood diseases in Chongqing is better ,it is recommended to strengthen the full quality control ,to establish emergency system ,and to improve the quality and level of laboratory .
5.Molecular cloning and expression of a serine protease family from Jellyfish Cyanea capillata
Yonghong ZHOU ; Hui ZHANG ; Xi CHENG ; Guoyan LIU ; Liming ZHANG
Chinese Journal of Biochemical Pharmaceutics 2015;(12):1-5
Objective To obtain a single toxin component from the jellyfish Cyanea capillata and provide a foundation for the further study on bioactivity and function of the serine proteases from C.capillata.Methods Primers designed with restriction enzyme were used to amplify the coding region of cDNAs (CcSP1, CcSP2 and CcSP3).PCR fragments were ligated with the pET-24a( +) vector to construct the recombinant plasmids (pET24a-CcSP1, pET24a-CcSP2 and pET24a-CcSP3).After screening and identification,the recombinant plasmids were transformed into the Rosetta (DE3).plysS for protein expression.After induction with IPTG, SDS-PAGE and Western-blot were used to detect the expression of the recombinant proteins.Results SDS-PAGE showed that the proteins of rCcSP1, rCcSP2 and rCcSP3 were expressed in a single band at about 34 kDa, 42 kDa and 42kDa, respectively.Western-blot detection with anti-His antibody further confirmed that these recombinant proteins were His-tagged CcSP1, CcSP2 and CcSP3 fusion protein were obtained.Conclusion Prokaryotic recombinant plasmids of C.capillata serine proteases are contructed and recombinant proteins are obtained, which establishes the foundation for future study on the function of serine proteases from jellyfish.
6.Evaluation of coronary heart disease risks in patients with psoriasis
Yan CHENG ; Xiaomei CHEN ; Xi DUAN ; Min ZHANG
Chinese Journal of Dermatology 2012;45(9):627-630
Objective To estimate the 10-year risk of coronary heart disease in patients with psoriasis,and to determine whether the risk profile is affected by disease duration,family history and clinical types of psoriasis.Methods Data were pooled from 322 inpatients with psoriasis and 297 inpatients with other skin diseases (151 cases of acute urticaria,33 drug eruption,113 herpes zoster) from December 2008 to December 2010 in the Department of Dermatology,West China Hospital of Sichuan University.Risks of coronary heart disease were estimated by using the Framingham risk score algorithm.Wilcoxon rank test,Kruskal-Wallis test and chi-square tests were used to evaluate the differences in risks and risk factors between the patients with psoriasis and controls.Results As far as the Framingham 10-year risk score was concerned,the difference was statistically significant between the patients with psoriasis and the control population (6% vs.4%,Z =4.342,P =0.000),as well as between patients with different clinical types of psoriasis (6% for psoriasis vulgaris vs.4% for pustular psoriasis vs.7% for psoriasis arthropathica vs.7% for erythroderma psoriaticum,H =8.484,P < 0.05),but was insignificant between patients with familial and sporadic psoriasis (6% vs.6%,Z =0.406,P > 0.05 ).No correlation was observed between the Framingham 10-year risk and psoriasis duration (P > 0.05 ).Conclusions Increased risks of coronary heart disease exist in patients with psoriasis compared with those with acute urticaria,drug eruption or hepers zoster,and in patients with psoriasis arthropathica or erythroderma psoriaticum compared with those with pustular psoriasis.The Framingham 10-year risk of coronary heart disease is uncorrelated with disease duration and unaffected by family history of psoriasis.
8.Resection of the cholesteatoma combined brain abscess with the access of back wall of maxillary sinus under nasal endoscopy and navigation.
Hua ZHANG ; Xi-cheng SONG ; Chun-ming XIU
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2012;47(5):420-421
Adult
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Brain Abscess
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Cholesteatoma
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surgery
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Endoscopy
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Female
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Humans
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Maxillary Sinus
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surgery