1.The status quo and future prospects of the next generation sequencing technologies in clinical diagnostics
Chinese Journal of Laboratory Medicine 2017;40(7):483-485
During the past decade, tremendous progress has been made in terms of speed, read length, and throughput, along with a sharp reduction in per-base cost.Together, these advances democratized next generation sequence (NGS) and paved the way for the development of a large number of novel NGS applications in clinical diagnostics, especially in the field of non-invasive prenatal detection, rare genetic disease and cancer companion diagnostics.As technology advances, long-read single molecule sequencing began to emerge.Single cell, long-reads, transcriptome, and low cost will be the NGS direction.Due to the special nature of clinical testing, the current NGS clinical application system,including genetic counseling, testing standards, quality control, supervision, database construction etc, does not match the national conditions well and still faces a few challenges, needs to be constantly improved through the routine clinical practice in the future.
2.Molecular diagnosis in China:present status and challenges ahead
Chinese Journal of Laboratory Medicine 2016;39(7):473-476
Molecular diagnosis is rapidly developed in recent years , mainly applicated in the diagnosis of hereditary disease , infectious pathogens, tumor susceptibility and molecular typing , companion diagnosis and prognosis assessment , playing more and more important role in many diseases diagnosis and treatment.Molecular diagnosis was developed from the eighties of the last century in our country .Nowadays, the mainly applied technologies in the clinical laboratory include fluorescence in situ hybridization , quantitative PCR, microarray and DNA sequencing. These molecular technologies make up for the insufficiency of routine testing and take up a central role in the development of modern laboratory medicine . With the continuous development in transformation research of molecular technology recent years , there will be more molecular diagnostic techniques applied in clinicaldiagnosis in the future .But it still exists some drawbacks in the performance of molecular diagnosis in our country according to the current situation , such as imbalanced regional development , mismatched policies, non-standardized laboratory construction , deficiency of quality control and supervision , etc., which requires the joint effort of the government , hospital, professional association and clinical laboratory itself to promote the healthy and orderly development of molecular diagnosis.
3.The canine model of neurogenic bladder and the urodynamics
Hua XIE ; Haiteng ZHAO ; Guohua LIU
Chinese Journal of Urology 2000;0(05):-
Objective To develop a canine model of neurogenic bladder and to evaluate it with urodynamics. Methods Eight female dogs were divided into 2 groups:4 in suprasacral and 4 in infrasacral group.The spinal cord was transected at the level of 5th~6th lumbar intervertebra foramen,and sacral cord was kept intact in suprasacral model while in infrasacral model it was destroyed completely.The urodynamic studies were performed in each dog at the time points of preopertation and 6 months postoperation in both groups.The parameters included bladder capacity,detrusor pressure,bladder compliance and urethral pressure. Results The dogs after operation could never move their tails and keep their hips dry.Their hind limbs presented flaccid paralyses and the abdomens dilated during the first postoperative week.Then the mobility of the hind limbs in both groups recovered slowly,but the abdominal signs were improved obviously only in suprasacral dogs.In suprasacral group,bladder capacity and compliance were decreased by 37.3% and 52.1%,respectively, but detrusor pressure (33.3%) and urethral pressure (17.3%) were significantly increased( P
4.Feasibility study of ECG-triggered non-contrast-enhanced magnetic resonance venography of lower extremities
Chuanchen ZHANG ; Jinfa XU ; Jun CHEN ; Yujin DI ; Guohua XIE
Chinese Journal of General Practitioners 2013;12(4):306-308
Twelve healthy volunteers underwent ECG-triggered non-contrast-enhanced magnetic resonance venography(NCE-MRV)of lower extremities on a 1.5T MR scanner.Image quality was assessed quantitatively and qualitatively with a 17-segment model.ECG-triggered (NCE-MRV) was successfully performed in all patients.Mean signal to noise ratio and contrast to noise ratio of lower extremities were 66 ± 23 and 53 ± 22 respectively.Excellent and good image qualities were achieved in 62% and 31% of all segments respectively without non-evaluable segment.Thus ECG-triggered NCE-MRV of lower extremities is feasible with reliable image quality.
5.Genotyping of K-ras exon 2 codons 12 and 13 mutations in colorectal cancer by pyrosequencing
Guohua XIE ; Xiaohong YAO ; Ping WU ; Lisong SHEN
Chinese Journal of Laboratory Medicine 2012;35(7):585-592
ObjectiveTo investigate the clinical significance of pyrosequencing assay for determining K-ras mutations in exon 2 codons 12 and 13 in clinical colorectal cancer tissues.Methods Genomic DNA,extracted from K-ras mutant cell lines SW480 (homozygous,c.35G > T), DLD-1 (heterozygous,c.38G > A) and wild-type HT-29,was first used as the sequencing template respectively to test the accuracy of pyrosequencing methodology.The SW480 and DLD-1 DNA was separately mixed with wild-type HT-29 DNA in proportions of 2%,3%,5%,10%,20%,30% and 50%,the sensitivity for mutation detection was measured separately by pyrosequencing assay and directed Sanger DNA sequencing in the serial DNA mixture samples.The pyrosequencing assay results were compared with the corresponding Sanger sequencing and the datas were analysized by Fisher exact test.Pyrosequencing analysis was then performed for screening K-ras exon 2 mutations at codons 12 and 13 on DNA isolated from a panel of 30 colorectal cancer samples derived fromclinicalformalin-fixed andparaffinembedded(FFPE)tissues.ResultsCancer cell lines with known K-ras mutations ( SW480 and DLD-1 ) were readily detectable by pyrosequencing-based analysis.When the proportions of mutant colorectal cancer cell line DNA were 5% and 10% content,the mutation rates of K-ras gene detected by conventional Sanger DNA sequencing were 33.3% (4/12) and 58.3% (7/12) respectively,whereas the mutation rates detected by pyrosequencingbased assay were 91.7% (11/12) and 100%(12/12) respectively,there were significant differences between those two sequencing methodology ( P <0.05).Furthermore,we found 10 patients with K-ras exon 2 point mutations at codons 12 and 13 by pyrosequencing-based assay from 30 colorectal cancer FFPE tissues,the point mutation rate was 33.3% (10/30) and all of the mutations determined were heterozygous.The codon 12 was most frequently affected [30% (9/30)].Mutations with the highest frequency were G > A transitions [ 50% ( 5/10 ) ],followed by G > T transversions [ 30% ( 3/10 ) ].Conclusion The pyrosequencing assay provides an accurate and sensitive method for mutation screening of K-ras exon 2 codons 12 and 13 in routine diagnostic specimens,thereby allowing the selection of the cancer treatment in clinical individualized practice.
6.Clinical value of catheter in pancreatic duct for prevention of post-EPBD pancreatitis
Yiyi HU ; Guoping DU ; Peng WANG ; Guohua LI ; Yunzheng XIE
Chinese Journal of Digestive Endoscopy 2015;(5):296-299
Objective To evaluate catheterization in pancreatic duct before endoscopic papillary bal-loon dilation (EPBD)to prevent pancreatitis after EPBD.Methods Forty-three patients with normal serum amylase levels,diagnosed as having bile duct stones,underwent EPBD.Twenty-three were assigned to experi-mental group,where catheters(ERCP imaging tube)were placed in pancreatic duct before EPBD,then the pa-pillary balloon was expanded to 10 mm.Twenty were assigned to control group where eight-millimeter-diameter papillary balloon was used to remove the stones.The serum amylase levels before EPBD,6 hours and 24 hours after EPBD,the incidence of pancreatitis and high serum amylase levels associated with EPBD,as well as the mean time and success rate of removing the stones of the two groups were compared.Results Post-EPBD pan-creatitis occurred in one patient in experimental group (4.35%),and seven in control group (35.00%), which was significantly different(P <0.05).Meanwhile,the mean levels of serum amylase 6 h and 24 h after EPBD in the experimental group were (102.61 ±98.99)U /L and (60.35 ±26.18)U /L respectively,lower than those in the control group (398.25 ±259.32)U /L and (230.50 ±281.31)U /L(P <0.05).After the papillary balloon was expanded to 10 mm in experimental group,the mean time of removing stones was (10.43 ±2.27)min,which was shorter than that of control group (17.90 ±4.49)min (P <0.05).Stone-re-moving rate of two groups had no difference and they all succeeded one time.Conclusion Placing catheter in pancreatic duct before EPBD to prevent pancreatitis after EPBD makes it easier to remove stones in shorter op-eration time.It can prevent pancreatitis and high amylase blood disease after EPBD.
7.Knowledge, attitudes and practices of combined oral contraceptives in Tianjin obstetrics and gynecology personnels
Yan HUO ; Yujuan ZHANG ; Jianmei WANG ; Jing YANG ; Guohua XIE
Tianjin Medical Journal 2015;(3):311-314
Objective To understand the knowledge, attitude, practice (KAP) status and relative demand to combined oral contraceptives (COCs) in medical staffs of obstetric and gynecological department in Tianjin, providing reference basis for the effective intervention measures. Methods By using random, stratified and clustered sampling approach, we selected 382 medical staffs of obstetric and gynecological department in Tianjin. A self-administered Questionnaire on COCs KAP was employed to survey the general characteristics, awareness of COCs knowledge, attitudes to COCs, service capabilities of contraceptive counseling, prescribing behavior and request of continuing education. Results The respondents showed de?fects in COCs indications, non-contraceptive benefits, relationship with cancer and birth defects. The average knowledge score was higher in doctors than that of nurses. The higher the titles and qualifications, the higher the knowledge score. A to?tal of 90.11%of respondents believed that strengthening the contraceptive guidance can help to reduce pregnancy. Strength?ening the interpretation of misunderstanding (81.04%) and enhancing the treatment and follow-up of adverse reactions (62.09%) can help to reduce stop taking. Only 25.82%of respondents could provide detailed COCs relative consulting servic?es;42.96%of obstetricians and gynecologists refused prescribing COCs for women over the age of 40 for the purpose of con?traception. A total of 93.13%medical personnel showed demand on relative training. Conclusion It’s necessary to perform continuing education to medical staffs via different intervention, so as to improve their cognitive level to COCs, ameliorate COCs relative attitudes and behavior, and help them providing better service to women of childbearing age.
8.Clinical outcomes of four-point fixation for posterior chamber intraocular lens dislocation
Xincheng SUN ; Guohua LU ; Yanwen JIA ; Ting PAN ; Liqin HUANG ; Yang XIE
Chinese Journal of Experimental Ophthalmology 2021;39(4):332-336
Objective:To observe the clinical effect of four-point fixation in patients with posterior chamber intraocular lens dislocation.Methods:A retrospective case series study was adopted.Sixteen patients (16 eyes) with posterior chamber intraocular lens dislocation who underwent suture suspension techniques with four-point fixation in Changzhou No.2 people's Hospital from January 2015 to January 2018 were enrolled.Postoperative effects were observed during follow-up, ranging from 6 to 13 months.The preoperative and 6-month postoperative uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), corneal endothelium cell count and astigmatism were measured and the differences were compared, and the relationships between total astigmatism and corneal astigmatism or intraocular lens induced astigmatism were analyzed, and the postoperative position of intraocular lens and complications were observed.This study adhered to the Declaration of Helsinki.The study protocol was approved by an Ethics Committee of Changzhou No.2 People's Hospital (No.2015-C-012-01).Written informed consent was obtained from each patient before surgery.Results:The mean preoperative UCVA (LogMAR) and BCVA (LogMAR) were 1.09±0.24 and 0.48±0.20, respectively, which were significantly improved to 0.30±0.12 and 0.26±0.13 at 6 months after operation, respectively.And the differences were statistically significant ( t=11.782, 3.795; both at P<0.01).The preoperative and 6-month postoperative corneal endothelium cell count were (2 270±360)/mm 2 and (2 032±327)/mm 2, respectively, and the difference was not significant ( t=1.921, P=0.074).The 6-month postoperative mean total astigmatism, corneal astigmatism and intraocular lens induced astigmatism were (-1.47±0.82)D, (-1.34±0.61)D and (-0.22±0.35)D, respectively.There was a highly positive correlation between total astigmatism and corneal astigmatism ( r=0.885, P<0.05), but there was no significant correlation between total astigmatism and intraocular lens induced astigmatism ( r=-0.432, P=0.095).No dislocation, deviation or torsion of intraocular lens were observed during the follow-up.Varying degree of symptoms of iridocyclitis were observed during early stage after operation, which disappeared after treatment.There were two cases of high intraocular pressure, which were normal after treatment.No retinal detachment, choroidal detachment, expulsive suprachoroidal hemorrhage, endophthalmitis, corneal endothelial decompensation or other complications occurred during and after operation. Conclusions:There is a stable position of intraocular lens, good visual acuity and few complications after four-point fixation with suture and suspension, which is a feasible method to treat dislocated intraocular lens.
9.Prevalence and prevention of Kaschin-Beck disease in different ecotypic areas in Gansu Province
Xiaoyan CHEN ; Guohua CHEN ; Jianyun SHAO ; Pengfei GE ; Ping LI ; Xiaoyan XIE ; Yongjian LIAO
Chinese Journal of Endemiology 2016;35(9):672-676
Objective To grasp the epidemic features of Kaschin-Beck disease in different ecotypic areas in Gansu Province,in order to provide ecological basis for Kashin-Beck disease control.Methods Totally 37 counties with Kashin-Beck disease were divided into four ecological areas,villages with historical serious condition in township and townships with historical serious condition in county were investigated.Clinical examination and Xray of right hand of all 7-12-year-old children in the villages were carried out,while investigation of prevention and control measures was performed.Results Among 27 966 children from four ecological areas,the clinical detection rate was 0.05% (14/27 966) and the X-ray positive rate was 1.26% (353/27 966),metaphyseal rate was 1.25% (350/27 966),bone-side positive rate was 0.01% (3/27 966) and no case of epiphyseal and carpal were discovered.The clinical detection rate in children in the four ecological areas was not statistically significant (x2() =7.757,P >0.05),the Loess Plateau-gully region of Longdong [0.09% (10/11 604)] > the Anyon area of Qinling of Longnan [0.04% (3/7 969)] > Alpine grassland meadow area of Gannan [0.02% (1/4 021)] > the Loess Plateau-hills region of Longzhong [0 (0/4 372)].The detected rate of X-ray in four ecological areas was statistically significant (x2 =18.133,P < 0.05),the Anyon area of Qinling of Longnan [1.49% (119/7 969)] > the Loess Plateau-gully region of Longdong [1.41% (164/11 604)] > the Loess Plateau-hills region of Longzhong [0.89% (39/4 372)] > Alpine grassland meadow area of Gannan [0.77% (31/4 021)].Comprehensive prevention and control measures on Kaschin-Beck disease were different in different ecotypic areas.Relocation,long-distance education and selenium supplement measures had not been implemented in the four ecological areas.Conclusion The epidemic situation of Kaschin-Beck disease is different in different ecotypic areas in Gansu Province,which maybe related to ecological environment,but is under a state of control.
10.Knowledge, attitudes and practices of preconception and prenatal care in Tianjin obstetrics and gynecology personnels
Jianmei WANG ; Yujuan ZHANG ; Yan HUO ; Jing YANG ; Guohua XIE ; Wenjing YIN
Tianjin Medical Journal 2015;(8):912-915
Objective To better understand the knowledge, attitudes, practice (KAP) and relative demand of precon?ception and prenatal care (PAPC) in medical staffs of obstetrics and gynecology department in Tianjin. Methods Using ran?dom, stratified and clustered sampling approach, we selected 382 obstetrics and gynecology personnels in Tianjin. A self-ad?ministered questionnaire on PAPC KAP was employed to survey their general characteristics, their awareness of PAPC knowledge, their attitudes to PAPC, their service capabilities of PAPC and their request of continuing education. Results The respondents were lacking of KAP in Calcium and Iron supplementation, alternative preconception examination and emerging prenatal examination but present good KAP in folic acid supplemen, necessary prenatal items and classic prenatal examination. Doctors′average knowledge score was higher than nurses′. The scores in primary health care institutions was significantly higher than that in tertiary and secondary medical institutions. Young and junior medical respondents showed higher awareness than older and senior ones. Most (91.21%) respondents believe that PAPC is necessary. But 86.54%of re?spondents are not confident enough to provide comprehensive PAPC services. There were 63.74%, 54.67%, 38.74% and 32.42%of the respondents who could provide special PAPC advisory of adverse pregnancy history, thyroid dysfunction, re?productive infections and diabetes respectively. The most urgent training contents include PAPC knowledge in presence of complications or risk factors, advances in prenatal diagnosis, nutrition during pregnancy and consulting skills. Conclusion It′s necessary to intervent obstetrics and gynecology personnels to improve their cognitive level to PAPC, as well as to amelio?rate relative attitudes and behavior so they can provide more scientific and comprehensive PAPC service.