The chemical reprogramming of unipotent adult germ cells towards authentic pluripotency and de novo establishment of imprinting

Although somatic cells can be reprogrammed to pluripotent stem cells (PSCs) with pure chemicals, authentic pluripotency of chemically induced pluripotent stem cells (CiPSCs) has never been achieved through tetraploid complementation assay. Spontaneous reprogramming of spermatogonial stem cells (SSCs) was another non-transgenic way to obtain PSCs, but this process lacks mechanistic explanation. Here, we reconstructed the trajectory of mouse SSC reprogramming and developed a five-chemical combination, boosting the reprogramming efficiency by nearly 80- to 100-folds. More importantly, chemical induced germline-derived PSCs (5C-gPSCs), but not gPSCs and chemical induced pluripotent stem cells, had authentic pluripotency, as determined by tetraploid complementation. Mechanistically, SSCs traversed through an inverted pathway of in vivo germ cell development, exhibiting the expression signatures and DNA methylation dynamics from spermatogonia to primordial germ cells and further to epiblasts. Besides, SSC-specific imprinting control regions switched from biallelic methylated states to monoallelic methylated states by imprinting demethylation and then re-methylation on one of the two alleles in 5C-gPSCs, which was apparently distinct with the imprinting reprogramming in vivo as DNA methylation simultaneously occurred on both alleles. Our work sheds light on the unique regulatory network underpinning SSC reprogramming, providing insights to understand generic mechanisms for cell-fate decision and epigenetic-related disorders in regenerative medicine.

Retrospective analysis and mining of data from 10 840 patients undergoing non-invasive prenatal screening / 中华医学遗传学杂志

OBJECTIVE@#To retrospectively analyze non-invasive prenatal screening (NIPS) data from two centers.@*METHODS@#The NIPS results of 10 840 samples were analyzed, including 21/18/13 trisomies (T21/T18/T13), sex chromosome and other autosomal aneuploidies, and copy number variants (CNVs). The maternal age, gestational week, body mass index and concentration of free fetal DNA (cffDNA) were also analyzed.@*RESULTS@#The average gestational age of the 10 840 pregnant women was (32.34±5.04) year old, and the average gestational week for NIPS was (17.60±3.55) week. The overall false positive rate for T21/T18/T13 was 0.11%, sensitivity was 100%, specificity was 99.89%, and positive predictive value was 81.5%. The positive predictive values for sex chromosome and other autosomal aneuploidies and CNVs were 56.67%, 11.76% and 83.33%, respectively. The incidence of T21/T18 in the elder women (35 years or elder) was 2.12 times(P 0.05) that of young women. cffDNA was in proportion to gestational week (r = 0.207) and in inverse proportion to body mass index (r = -0.177). It has increased slowly before 15 weeks of gestation and thereafter at a rate of 0.5% per week after the 16th week.@*CONCLUSION@#The performance of NIPS in this study is by large close to the reported in the literature, and the results can provide a reference for further study.

Correction of β-thalassemia mutant by base editor in human embryos

β-Thalassemia is a global health issue, caused by mutations in the HBB gene. Among these mutations, HBB -28 (A>G) mutations is one of the three most common mutations in China and Southeast Asia patients with β-thalassemia. Correcting this mutation in human embryos may prevent the disease being passed onto future generations and cure anemia. Here we report the first study using base editor (BE) system to correct disease mutant in human embryos. Firstly, we produced a 293T cell line with an exogenous HBB -28 (A>G) mutant fragment for gRNAs and targeting efficiency evaluation. Then we collected primary skin fibroblast cells from a β-thalassemia patient with HBB -28 (A>G) homozygous mutation. Data showed that base editor could precisely correct HBB -28 (A>G) mutation in the patient's primary cells. To model homozygous mutation disease embryos, we constructed nuclear transfer embryos by fusing the lymphocyte or skin fibroblast cells with enucleated in vitro matured (IVM) oocytes. Notably, the gene correction efficiency was over 23.0% in these embryos by base editor. Although these embryos were still mosaic, the percentage of repaired blastomeres was over 20.0%. In addition, we found that base editor variants, with narrowed deamination window, could promote G-to-A conversion at HBB -28 site precisely in human embryos. Collectively, this study demonstrated the feasibility of curing genetic disease in human somatic cells and embryos by base editor system.

Design and Application of Vocational Competency Assessment System / 医学信息学杂志

Based on the characteristics that most patients in Vocational Rehabilitation Department of Guangdong Provincial Work Injury Rehabilitation Hospital are patients with occupational injuries,the paper analyzes the hospitalized business process,concretely introduces the main functional modules,design framework,safety requirements,database design,etc.of the vocational competency assessment system.The application of this system provides references for rehabilitation doctors and vocational rehabilitation therapists to make training schemes,strengthens patient information management,improves working efficiency and service level.

Clinical analysis of preimplantation genetic diagnosis with HLA matching for beta-thalassemia / 中华妇产科杂志

Objective To investigate the efficacy and feasibility of preimplantation genetic diagnosis (PGD) with human leukocyte antigen (HLA) matching for beta-thalassemia. Methods A total of 43 referred beta-thalassemia couples, with at least on child in need of hematopoietic stem cell transplantation (HSCT), underwent PGD for HLA matching at the First Affiliated Hospital of Sun Yat-sen University from 2010 to 2015. PGD cycles of these couples were retrospectively analyzed, and 15 infants born from PGD-HLA were followed up. Results A total of 84 oocyte retrieval cycles were performed, providing 14±7 oocytes per cycle. Fifty nine embryos biopsied cycles were done, including 24 cleavage stage and 35 blastocyst stage biopsy cycles. In cleavage stage, 259 embryos were biopsied, 93.4% (242/259) of them with conclusive molecular diagnosis, and the percentage of unaffected embryos (normo-homozygote and heterozygote) was 71.4%(185/259). The percentage of HLA matched unaffected embryos was 9.3%(24/259). In blastocyst stage, 306 embryos were biopsied, while 93.8% (287/306) of them were conclusive, and the percentage of unaffected embryos was 70.6% (216/306). The percentage of HLA matched unaffected embryos in blastocyst stage biopsy was 14.4%(44/306), which was higher than in cleavage stage biopsy (P<0.05). Forty three female carriers underwent 48 embryo transfer cycles including 3 fresh and 45 frozen-thawed embryo transfer cycles. Three fresh embryo transfer cycles were done after cleavage stage biopsy, resulted in a birth of healthy twins born at 36 weeks′gestation. All the embryos were frozen after blastocyst biopsied. Totally, 54 frozen-thawed embryos that were transferred in 45 frozen-thawed embryo transfer cycles included 25 embryo from cleavage stage biopsy and 29 embryo from blastocyst stage biopsy, and 42 of them were HLA matched. Clinical pregnancy rate and implantation rate per cycle in frozen-thawed embryo transfer were 38%(17/45) and 37%(20/54) respectively. A total of 15 infants were born, 2 were from a fresh embryo transfer cycle, and 13 were from frozen-thawed embryo transfer cycles. Results of prenatal diagnosis from delivered cases were matched to that of PGD. Four sick children have been cured by HSCT from these HLA matched born siblings. Conclusion PGD with HLA matching is an established method for conceiving a child who may donate hematopoietic stem cells to save an ill sibling.

Difference of morphology and proliferation ability between diabetes mellitus-derived ADSCs and normal ADSCs / 中华医学美学美容杂志

Objective To investigate the morphological characteristics and proliferation ability of diabetes mellitus-derived adipose-derived stem cells (ADSCs) by comparing with normal-derived ADSCs.Methods The ADSCs could be achieved from diabetes mellitus' adipose tissue by the similar method of normal ADSCs isolation and culture,and then the differnce was compared between the two groups about their morphologies under microscope,and the proliferation ability of two groups was determined by CCK-8.Results ADSCs in patients with diabetes were obvious hypertrophy and irregular in morphology.A values of ADSCs in diabetes and non-diabetes were 0.210+0.002 and 0.390+0.006 in 1st day;0.250+0.015 and 0.443+0.023 in 2nd day;0.368+0.014 and 0.726+0.033 in 3rd day;0.368+0.014 and 0.726+0.033 in 4th day;1.767+0.072 and 3.153+0.067 in 5th day and 1.810+0.072and 3.170+0.021 in 6th day,respectively.The difference was statstically significant at the beginning from 4th day (P＜0.05).Conclusions There is obvious difference of the microscopic morphology between the diabetes mellitus-derived ADSCs and normal-derived ADSCs.The proliferation ability of the diabetes mellitus-derived ADSCs is lower than normal-derived ADSCs.These difference could be closely related to ulcerous non-healing wounds in patients with diabetes mellitus.

Preimplantation genetic diagnosis for carriers of thalassemia and chromosomal abnormality / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To provide preimplantation genetic diagnosis(PGD) for two couples carrying thalassemia mutations and chromosomal abnormalities.</p><p><b>METHODS</b>Couple 1 were both carriers of β 41/42 thalassemia mutations, while the husband has carried a reciprocal translocation with a karyotype of 46,XY,inv(9)(p11;q13),t(11;22)(q25;q13). Couple 2 were both carriers of α (-SEA) thalassemia mutation. Their chromosome karyotypes were both normal, but had two spontaneous abortions. The couples had received 1 and 3 blastocysts respectively through in vitro fertilization(IVF) cycles. Following the biopsy, the cells underwent whole genome amplification, and the amplified DNA from each embryo was subjected to genetic testing and a 23-chromosome single nucleotide polymorphism(SNP) microarray assay.</p><p><b>RESULTS</b>The embryo of couple 1 was diagnosed as carrier of β 41/42 thalassemia with euploid chromosomes. The embryo was transferred and resulted in intrauterine pregnancy. Similarly, an embryo of couple 2 was verified as carrier of α (-SEA) thalassemia with euploid chromosomes.</p><p><b>CONCLUSION</b>PGD for aneuploidy coupled with testing for single gene disorders via trophectoderm biopsy and whole genome amplification is feasible. The approach can attain diagnosis with minimal damage with sound clinical outcome.</p>

CRISPR/Cas9-mediated gene editing in human tripronuclear zygotes

Genome editing tools such as the clustered regularly interspaced short palindromic repeat (CRISPR)-associated system (Cas) have been widely used to modify genes in model systems including animal zygotes and human cells, and hold tremendous promise for both basic research and clinical applications. To date, a serious knowledge gap remains in our understanding of DNA repair mechanisms in human early embryos, and in the efficiency and potential off-target effects of using technologies such as CRISPR/Cas9 in human pre-implantation embryos. In this report, we used tripronuclear (3PN) zygotes to further investigate CRISPR/Cas9-mediated gene editing in human cells. We found that CRISPR/Cas9 could effectively cleave the endogenous β-globin gene (HBB). However, the efficiency of homologous recombination directed repair (HDR) of HBB was low and the edited embryos were mosaic. Off-target cleavage was also apparent in these 3PN zygotes as revealed by the T7E1 assay and whole-exome sequencing. Furthermore, the endogenous delta-globin gene (HBD), which is homologous to HBB, competed with exogenous donor oligos to act as the repair template, leading to untoward mutations. Our data also indicated that repair of the HBB locus in these embryos occurred preferentially through the non-crossover HDR pathway. Taken together, our work highlights the pressing need to further improve the fidelity and specificity of the CRISPR/Cas9 platform, a prerequisite for any clinical applications of CRSIPR/Cas9-mediated editing.

Preimplantation genetic diagnosis of infantile malignant osteopetrosis in a Chinese family / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the application of preimplantation genetic diagnosis (PGD) for infantile malignant osteopetrosis (IMO).</p><p><b>METHODS</b>For a family affected with IMO, PGD was provided using combined parental mutation detection and haplotype constructions with microsatellite markers spanning the TCIRG1 gene. Prenatal diagnosis was performed on the chorionic villus and amniocentesis samples by direct sequencing.</p><p><b>RESULTS</b>Prenatal diagnosis showed that the fetus by the third pregnancy has carried the parental mutations [c.242delC (p.Pro81Argfs*85) and c.1114C>T (p.Gln372*)], and the pregnancy was terminated. PGD was subsequently performed through mutations detection and haplotype analyses following whole genome amplification (WGA) of each of 13 cells. The results showed that 6 of the 13 embryos were unaffected, 3 were carriers and 4 were affected. Well developed unaffected/carrier embryos were selected and transferred into the uterus. A single pregnancy was confirmed. Subsequently pre- and post-natal diagnoses have confirmed development of a healthy child.</p><p><b>CONCLUSION</b>The study demonstrated the advantage of PGD over prenatal diagnosis when natural pregnancies have repeatedly produced IMO children/fetuses.</p>

Reliability and Validity of the Lam Assessment of Employment Readiness for Injured Workers / 中国康复理论与实践

@#Objective To measure the reliability and validity of the Lam Assessment of Stages of Employment Readiness (LASER) Putonghua version for injured workers, and observe the confidence of return to work on different preparation stages. Methods 85 injured workers with limb fractures were included. The data was obtained through face-to-face structured interview. The test-retest reliability and internal consistency were measured. Factor analysis was used to examine construct validity of the Putonghua version LASER. Results Principle component analysis extracted four factors, which was consistent with the original version of LASER. Intra- class correlation coefficient (ICC) of test-retest ranged 0.27~0.89, whereas the internal consistence among these 4 stages ranged 0.691~0.796. There were significantly differences in confident scores in different stages among 3 different confidence groups. Conclusion The structure validity of Putonghua version of LASER is useful for reflecting the readiness of injured workers' return to work. However, the reliability coefficient is rather low in some of the items, which could be resulted in incorrect judgment of readiness of return to work of injured workers. The further study on items correction and development is apparent.

Clinical investigation to compare aCGH and FISH in preimplantationgenetic diagnosis of chromosome translocation carriers / 中华妇产科杂志

Objective To investigate the clinical use of array comparative genomic hybridization (aCGH) with fluorescence in situ hybridization (FISH) in preimplantion genetic diagnosis (PGD)for reciprocal and Robertsonian translocation carriers.Methods From Jan.2012 to Jun.2013,a total of 220 PGD cycles from 151 reciprocal translocation and 62 Robertsonian translocation carrier couples,including 33 cycles for reciprocal translocation carriers and 22 cycles for Robertsonian translocation carriers performed using array CGH,and 119 cycles for reciprocal translocation carriers and 46 cycles for Robertsonian translocation carriers performed using FISH were retrospectively studied.The rate of accurate diagnosis was compared between two methods.Results Normal and/or balance rates of the two translocated chromosomes detected by aCGH for both reciprocal and Robertsonian translocation carriers were 38.20％ (123/322) and 67.20％ (127/189),significantly higher than 15.39％ (195/1 267) and 30.75％ (202/657) by FISH (all P ＜0.05).Abnormal rates of the two translocated chromosomes detected by aCGH for both reciprocal and Robertsonian translocation carriers were 59.32％ (191/322) and 30.69％ (58/189),significantly lower than 83.03％ (1 052/1 267) and 67.43％ (443/657) by FISH (all P ＜ 0.05).And the rate of aneu ploidy in non-translocated chromosome from reciprocal translocation embryos was 20.19％ (65/322),which was significantly lower than 38.62％ (13/189) from Robertsonian translocation embryos (P ＜ 0.01).Conclusions Normal and/or balance rates of the two translocated chromosomes detected by array CGH were significantly higher than FISH.And the rate of aneuploidy in non-translocated chromosomes from reciprocal translocation embryos was significantly lower than that from Robertsonian translocation embryos.

A preliminary study on the application of array comparative genomic hybridization for preimplantaion genetic diagnosis / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the value of array comparative genomic hybridization (array CGH) technique for preimplantation genetic diagnosis (PGD).</p><p><b>METHODS</b>Array CGH was performed on three types of cells, which included 3-5 cells isolated from B2/C38/A1 embryonic stem cell lines, single cells isolated from two discarded normal fertilized embryos, and 10 blastocysts biopsied from 5 couples undergoing PGD for chromosomal translocations. For the 10 blastocysts, 8 were abnormal embryos, 1 appeared to be normal but showed arrested development, and 1 embryo was without any fluorescence signals. 24sure V3 or 24sure+ array chips were applied for CGH analysis. The results were analyzed with a BlueFuse Multi software.</p><p><b>RESULTS</b>(1) The results of cells from B2/C3/A1 embryo stem cells by array CGH were consistent with karyotyping analysis. (2) For the 6 single cell samples from two discarded embryos, 2 blastomeres from one embryo were diagnosed as with aneuploidy and a normal karyotype, respectively. Two out of 4 blastomeres biopsied from another embryo were normal, whilst the remaining two were diagnosed with aneuploidies of -22 and +13. Repeated detection with 24sure+ array was consistent with the 24sure V3 result. (3) Ten cell masses from 10 embryos in PGD cycles were successfully analyzed with array CGH, among which four were confirmed with fluorescence in situ hybridization (FISH) on day 3. In two of them, array CGH confirmed FISH diagnosis. For the remaining two, additional aneuploidies for chromosomes not tested by FISH were discovered by array CGH. Another embryo diagnosed as no signal by FISH was found to have trisomy 13 by array CGH. The remaining 5 embryos also showed discordant results by FISH and array CGH. One embryo from a Robertsonian translocation carrier was found to have monosomy 13 by FISH but trisomy 14 and additional aneuploidies by both 24sure V3 and 24sure+ chips. One embryo with many fragments and arrested development by D5 showed discordant results by FISH and array CGH. However, the FISH and array CGH results for other two embryos from this reciprocal translocation carrier were consistent. Three embryos with inconsistent results by FISH and array CGH had a chromosomal translocation involving q11 region.</p><p><b>CONCLUSION</b>Array CGH is useful for PGD applications for its capability to detect structural chromosomal abnormalities through screening of aneuploidies. However, the 24sure V3 array may not suit detection of translocations with breakpoints close to the q11 region of chromosomes.</p>

Clinical analysis of 100 preimplantation genetic diagnosis cycles / 中华妇产科杂志

Objective To investigate influence of chromosomal translocations on early embryo development and to evaluate the efficacy and feasibility of preimplantation genetic diagnosis (PGD)techniques through clinical analysis on PGD cycles. Methods Embryo development, efficacy of PGD and clinical outcome of 100 cycles were studied retrospectively, including 23 cycles with Robertsonian translocations, 19 cycles with reciprocal translocations, and 58 cycles for α-Thalassaemia. Results Among 354 embryos biopsied by PGD for translocations, 321 (90. 7% ) presented fluorescence in situ hybridization (FISH) results. The rate of normal/balanced embryos in the Robertsonian translocation was 38. 3% (64/167),which was significantly higher than 20. 8% (32/154) in the reciprocal translocation group. Amplification was achieved in 443 blastomeres from 537 embryos in Thalassaemia group, which given to an amplification efficiency rate of 82. 5% ( 443/537 ). Totally, 140 normal homozygous, 112 heterozygotes and 155 affected homozygous embryos were identified, while 36 embryos had uncertain result. The successful diagnostic rate was 75.8% (407/537). After 3 days in the translocation groups, the rate of normal and/or balanced translocations in biopsed embryos with ≥7 cells was 34. 4% (77/224), which was significantly higher than 19. 6% ( 19/97 ) of biopsed embryos with ＜ 7 cells. After 4 days, the compaction rate in normal/balanced embryos was 59.4% ( 57/96 ), which was significantly higher than 34. 2% ( 77/225 ) in imbalanced embryos significantly. Seventy-five embryos transferred in 37 cycles with translocations group led to clinical pregnancy rate of 27.0% (10/37), and 170 embryos transferred in 58 cycles with Thalassaemia got a clinical pregnancy rate of 43. 1% ( 25/58 ) . Conclusions PGD can provide management efficiently for both chromosome translocations and Thalassaemia. Translocations might have slightly negative impact on embryo development before implantation.

Contributors of Return to Work for a Cohort of Spinal Cord Injured Workers / 中国康复理论与实践

@#Objective To explore the rate of return to work among a cohort of spinal cord injury (SCI) who were at least 18 months post injury and some psychosocial factors contributing to return to work. MethodsA convenient sampling method was adopted and total 161 subjects were involved. The demographic characteristic and psychosocial variable were collected by 6 self-reported questionnaires: World Health Organization Disability Assessment Schedule Ⅱ, Acceptance of Disability Scale, Rosenberg Self-Esteem Scale, Center for Epidemiologic Studies Short Depression Scale, Generalized Self-Efficacy Scale and Multidimensional Scale of Perceived Social Support. Self-administered, telephone and face-to-face interview were the manners to capture data. ResultsThe return to work rate is 31%. The result generated from Logistic regression showed that the type of SCI (paraplegia or quadriplegia) （OR=4.397）, acceptance of disability (OR=0.979), disability assessment level (OR=0.948), and the impact of belief to activities of daily living (OR=0.681) were the contributors for successful return to work. ConclusionFor those who suffering from SCI after 18 months, both psychosocial adjustment factors and physical functioning may have the great impacts for the outcomes of return to work rather than that of external factors, such as social supports.

Evaluation of the fidelity of multiple displacement amplification from small number of cells / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To evaluate the fidelity of multiple displacement amplification (MDA) from small number of cells (1-10 cells) by 10K 2.0 SNP mapping array.</p><p><b>METHODS</b>A fibroblast cell line (Tri-18; GM02732, 47, XY, +18) was used as the template, and 6 groups were set up in the study. Groups A and B were positive and negative control, respectively; groups C-F were experimental groups involving the MDA products from 1, 2, 5 and 10 cells respectively. In combination of single nucleotide polymorphism (SNP) array, the product of each group was assessed based on the genome coverage, loss of heterozygosity (LOH) rate and allele dropout (ADO) rate.</p><p><b>RESULTS</b>The nonspecific product of negative control presented an average call rate of 3.2%. The genome coverage of the MDA product increased from 86.4% to 96.4% with the increasing number of template from 1 to 10 cells, while the LOH rate and ADO rate decreased significantly (P<0.05).</p><p><b>CONCLUSION</b>MDA is a highly efficient and reliable method for whole genome amplification. The fidelity of MDA will be improved significantly with the increasing number of template cells. 10K 2.0 SNP mapping array is a quick, accurate and comprehensive method to evaluate the fidelity of amplified DNA products, but the ADO SNPs should be distinguished from those of preferential amplification from the LOH loci to avoid errors.</p>

Genetic analysis of chorionic villi specimen in spontaneous abortion using various methods / 中华妇产科杂志

Objective To explore the efficacy of multiplex ligation-dependent probe amplification (MLPA)combined with fluorescence in situ hybridization(FISH)and comparative genomie hybridization (CGH)combined with FISH in genetic analysis of chorionic villi specimen(CVS)of spontaneous abortion.Methods CGH+FISH and MLPA+FISH were used for genetic analysis of 29 CVS from spontaneous abortion and 6 normal CVS from selective abortion,in the mean time,those results were compared with conventional eytogenetic karyotyping.Results The report time were 40 hours in MLPA+FISH and 120 houm in CGH+FISH.The mean time of chorionic villi culture was(240±72)hours.The successful rate of specimen analysis were 97%(34/35)in CGH,100%(35/35)in MLPA,100%(35/35)in FISH and 91%(32/35)in conventional cytogenetic karyotyping.Apart from 1 case failed in CGH analysis,the results from MLPA+FISH were almost similar to that from CGH+FISH,however,that 1 specimen failed in CGH were detected successfully by MLPA+FISH.The discrepancy rate were 13%(4/31)in CGH+FISH and 12%(4/32)in MLPA+FISH respectively when compared with conventional cytogenetic analysis.Conclusions MLPA+FISH analysis present shorter detecting time and achieve 100%tale of successful report.This combined method was an important adjuvant approach to conventional cytogenetic karyotyping in CVS from spontaneous abortion.

Detection of Aneuploidy from Single Cells by Array-Comparative Genetic Hybridization / 中山大学学报(医学科学版)

[Objective] To set up an optimized protocol for aneuploidy detection from single cells through Array- Comparative Genetic Hybridization (CGH).[Method] Two cell lines,trisomy 18 (Tri-18;GM02732,47,XY,+18) and chromosome 4 segment deletion [sDel-4;GM00343,46,XY,4(del) (qter ＞ p14)],were used in the study.In combination of 10 k 2.0 SNP mapping array platform and multiple displacement amplification (MDA),the diagnostic accurate rates of MDA product from single cells of the two cell lines using gDNA and single-cell MDA product as reference were compared.[Result] An extremely lower call rate (3.2 ± 1.2)% in the negative control group was observed compared to the experiment groups.When the single-cell MDA product was used as reference,the standard deviations of Log2 (signal intensity ratio) were significantly decreased in both groups,compared with when the gDNA as reference (P ＝ 0.004).Through CNAT analytic software,some specific chromosomes (16,17,19,and 22) presented obvious preferential amplification (PA) when the gDNA was used as reference,but this PA could be eliminated when single-cell MDA product was used as reference.[Conclusion] 10 k 2.0 SNP mapping array in combination with MDA could be a quick,highly efficient and accurate method to detect aneuploidy in single cells.

Efficiency comparison between two preimplantation genetic diagnostic methods for chromosomal translocation carriers / 中华妇产科杂志

Objective To compare the diagnostic efficiency between blastomere preimplantation genetic diagnosis (PGD) and polar body PGD for chromosomal translocation carriers. Methods Group A had 8 cycles using whole painting probes for the first polar body diagnosis, while group B had 29 cycles using two subtelomeric probes and one centromeric probe for the blastomere diagnosis. Results The fertilization rate of group A was significantly lower than group B [66. 1% (72/109) vs 85.2% (304/357) , P < 0.05]. There was no significant difference in the successful biopsy rate between two groups. However, group A had a significantly higher loss rate during fixation and higher no signal rate after fluorescence in situ hybridization [ FISH, 9. 6% (12/104) vs 1.6% (4/252), 11.2% (10/89) vs 3.0% (7/233) ]. Totally, the diagnostic efficiency in group A (72. 5% ,79/109 ) was significantly lower than that in group B( 89. 8%, 230/256, P < 0. 05 ). Although both the clinical pregnancy rate( 3/7 ) and implantation rate( 22. 2% ,4/18 ) of group A were higher, the differences were not statistically significant ( P > 0.05 ). Conclusion Both methods can be used efficiently in the PGD for chromosomal translocation carriers. Blastomere PGD has a higher diagnostic rate.

Effect of Flexion Angle of Knee Joint on Co-contractions of Agonist and Antagonist Muscles / 中国康复理论与实践

@# Objective To test the effect of different flexion angles of knee joint on the myoelectric activity and torque of quadriceps femoris and hamstring muscle when these muscles contracting.MethodsElectromyographic activities and isometric torque measurements were performed on 10 healthy subjects at 30°, 60° and 90° of knee joint flexion.ResultsThe results indicated that the greatest maximal voluntary isometric contracture-torque of quadriceps femoris occurred during knee extension at 60° of knee flexion ( P<0.01). However, no significant relationship of maximal voluntary isometric contracture-electromyography and maximal voluntary isometric contracture-torque of quadriceps femoris were found in 10 subjects. But when knee joint was at 90° flexion, hamstring muscle had a greatest neuro-myoelectric activity.ConclusionThe exercise of maximal voluntary isometric contraction of quadriceps femoris and hamstrings muscles at certain knee joint angle can help to maintain the stability of knee joint.

Reliability and Validity of Test of BTE Primus Grip Attachment / 中国康复理论与实践

@# Objective To test the test-retest reliability for the BTE Primus grip attachment.Methods30 healthy adults were recruited to test the grip strength of BTE Primus grip attachment and Jamar grip tool in one day, the 2nd retest was conducted 7 days late.ResultsThe BTE Primus grip tool was found to be reliable (ICC = 0.957, 95%CI = 0.908～0.980) and valid ( r=0.842, P<0.01).ConclusionBTE Primus grip attachment can be applied when evaluating hand function in clinic.