mRNA Expression of Aquaporins in Human Luteinized Granulosa Cells from Different Diameter Follicles / 中山大学学报(医学科学版)

ObjectiveTo investigate the mRNA expression levels of various aquaporins （AQPs） in luteinized granulosa cells from follicles of different diameters. MethodsFrom March 25， 2022 to September 23， 2022 in our reproductive medicine center， 48 women undergoing in-vitro fertilization （IVF） were enrolled and divided into the antagonist group and the agonist group according to the ovarian stimulation protocol. Follicular fluid samples were collected on the day of oocyte pick-up and granulosa cells were extracted from follicles of different diameters： small （<13 mm）， medium （13~18 mm） and large （≥18 mm）. After RNA quantification， 22 cases （66 samples） were included for analysis and mRNA expression levels of AQPs were compared among the three follicle groups. ResultsThe mRNA expression of aquaporin 2 （AQP2） in luteinized granulosa cells increased with the increase of follicle diameter （linear trend P = 0.004） and the difference was statistically significant between two groups of large and small follicles （P = 0.017）. Statistical difference was found in the antagonist group （P = 0.049 6）， but not in the agonist group （P = 0.108）. ConclusionThe mRNA level of AQP2 in luteinized granulosa cells increases with the increase of follicle diameter and its expression is related to the ovarian stimulation protocol， suggesting that AQP2 may play a role in follicle growth and follicular fluid formation， and its mRNA expression level may be regulated by follicle stimulating hormone （FSH） and luteinizing hormone （LH）.

Theoretical and Clinical Studies of Integrated Traditional Chinese Medicine and Western Medicine for Infertile Women with Diminished Ovarian Reserve / 中国实验方剂学杂志

Infertility with diminished ovarian reserve(DOR) is a major problem in the field of reproductive health and it has attracted great attention worldwidely.Function deficiency of the kidney is one of the fundamental pathogenesis for DOR.Traditional Chinese medicines(TCMs) have a long history with rich experience for the treatment of infertility.Some TCMs are very effective in the treatment of kidney deficiency for infertility with DOR.The integrated TCMs and western medicine,and combination of disease differentiation and syndrome differentiation may help for diagnosis and treatment of infertility with DOR.We adopt the concept of unified treatment for special disease,and the methods and principle of treatment can be used.Therefore,we adopt the TCM concept of kidney-tonifying,blood-nourishing,liver-dispersing and spleen-invigorating.The TCMs kidney-tonifying formulae are added and subtracted.TCMs can regulate the reproductive function via multiple systems for simultaneous conditioning of follicular development and ovulation.At the same time,a hypothesis of " simultaneous conditioning of follicular development and ovulation" was proposed.Two-stage therapy with integrated TCMs and western medicine has been used,mainly for increasing the number of eggs,and improving follicle quality.The goal is to achieve simultaneous conditioning of follicular development and ovulation and ultimately for effective treatment of infertility with DOR.

Effect of Long-time Slow-frozen Storage on Epigenetic Changes of Histone in Cleavage-stage Embryos / 中山大学学报(医学科学版)

@#【Objective】To investigate the impact of long- term storage time on epigenetic modification of histone in human cleavage stage embryos.【Methods】According to the length of storage time，donated embryos after slow-freezing were divided into 3 groups ：6-year group ，9-year group ，and 12-year group ，while the control group consisted of donated fresh embryos. Immunocytochemistry was performed to compare the expression levels of HDAC1， H3K9ac， H3K4me3 ，and H3K9me3 among 4 groups. Transcription levels of HDAC1 ，SUV39H1 ，SETDB1 ，and KDM5A were analyzed through Single-Cell qRT-PCR.【Results】The relative abundances of HDAC1 and SUV39H1 mRNA showed no significant differences among 4 groups（P > 0.05）. SETDB1 exhibited a climbing pattern as storage time increased，but no significant difference was observed（P > 0.05）. There were no differences in H3K9 trimethylation and H3K9 methylation among 4 groups. However ，the expression level of KDM5A increased with the increasing storage time（P < 0.05）.【Conclusions】 Storage time did not affect the expression of deacetylase HDAC1，methylase SUV39H1 and SETDB1. H3K9ac/me3 and H3K4me3 also exhibited no significant difference as the storage time increases. However ，the increasing storage length might induce the elevating expression of demethylase KDM5A，which may be associated with inhibition of embryonic transcription.

Established a Preimplantation Genetic Testing-derived and Xeno-free Human Embryonic Stem Cell Line / 中山大学学报(医学科学版)

@#【Objective】 A human embryonic stem cell line derived from Preimplantation genetic testing （PGT） embryos was established in a xeno- free stem cell culture system to provide disease models for medical research. 【Methods】The xeno-free culture system using xeno-free human foreskin fibroblast feeder layers（XF-HFF）mixed with commercially available chemically-defined medium（CDM）was assessed. In the culture system，a new hESC cell line was established using discarded embryos derived from PGT in patients with chromosomal balance translocation.【Results】The new availabled stem cell line was successfully cultured in the xeno-free culture system for a long time（> 45 passages）. The karyotype analysis revealed that the new line kept the same karyotype over 45 passages. Moreover，the expression of pluripotent markers was detected by fluorescent immunostaining including SSEA- 3，SSEA- 4，SSEA- 1，TRA- 1- 60， and TRA-1-81. RT-PCR analysis showed that the stem cell markers were present in hESC grown on XF-HFF-CDM. In addition，the teratoma formation analysis demonstrated that the cells cultured in XF-HFF/CDM maintained their pluripotency in vivo.【Conclusions】Our study may provide the possibility to establish embryonic stem cells with certain pathogenic genes，which could be applied for clinical research and treatment.

Comparison of clinical pregnancy rates between two types of endometrial preparation protocols for patients with thin endometrium in frozen-thawed embryo transfer cycles / 中国实用妇科与产科杂志

OBJECTIVE: To compare the clinical pregnancy rates between two types of endometrial preparation protocolsnatural cycle（NC）and hormone replacement cycle（HRT）-in patients with thin endometrium in the frozen-thawed embryo transfer（FET）cycles.METHODS: From January 2012 to December 2018,FET patients with endometrial thickness ≤7 mm on the day of human chorionic gonadotropin（h CG）trigger in Reproductive Medicine Center of the First Affiliated Hospital of Sun Yat-sen University were selected as research subjects.According to the endometrial preparation protocols,they were divided into NC group and HRT group.Totally 117 pairs were successfully matched using the propensity score matching method.The matching variables were age,embryo type and number of transferred embryos,and the embryo implantation rate and clinical pregnancy rate of the two matched groups were compared.RESULTS: There was no significant difference in embryo implantation rate（36.47% vs. 39.03%）or clinical pregnancy rate（44.40% vs. 52.10%）between NC group and HRT group（P> 0.05）.CONCLUSION: NC group and HRT group had similar pregnancy rate in patients with thin endometrium in FET cycles.Individualized protocols can be adopted according to the characteristics of patients with thin endometrium.

Effects of M II stage oocytes zona pellucida birefringence on pregnancy outcome

OBJECTIVE@#To explore the effects of different M II stage oocytes zona pellucida birefringence on pregnancy outcome.@*METHODS@#A total of 46 couples with infertile which induced by single cause received in-vitro fertilization treatment were analyzed retrospectively, and randomly divided into the high zona birefringence (HZB)/HZB group, HZB/low zona birefringence (LZB) group and LZB/LZB group according to different oocytes zona pellucida birefringence. Intracytoplasmic sperm injection outcome was analyzed and compared.@*RESULTS@#The proportion of HZB oocytes, implantation rate and the pregnancy rate were decreased in three groups (HZB/HZB group>HZB/LZB group>LZB/LZB group) (P0.05). Logistic regression analysis showed that factors affect M II stage oocytes zona pellucida birefringence were age, basal FSH level and the LH level on the day of HCG injection. Age and FSH levels were negatively correlated with the single oocyte zona pellucida birefringence; While the LH level on the day of hCG injection was positively correlated with the single oocyte zona pellucida birefringence.@*CONCLUSIONS@#The primary influence factors on M II stage oocytes zona pellucida are age, basal FSH level and the LH level on the day of hCG injection. The birefringence value of zona pellucida can affect the pregnancy outcome.

A follow-up study on children conceived through intracytoplasmic sperm injection / 中华流行病学杂志

Objective To investigate the perinatal complications, birth defects and growth of children conceived through intracytoplasmic sperm injection (ICSI). Methods A total of 575 children conceived by ICSI in our reproductive medical center, were studied. The follow-up study would include items as pregnant complications, neonatal complications, birth defects in perinatal period, subsequently detected birth defects, body weight and body length/height growth. Results Prematurity and low birth weight of ICSI children were higher in the multiple births than in the singleton births. The rates of materal gestational hypertension, neonatal asphyxia, respiratory distress syndrome, infection diseases were higher in the multiple pregnancies than in the singleton pregnancies(P＜0.05). Eleven ICSI children had died. Ten of them died in the neonatal period and they were preterm infants. One fullterm singleton ICSI child died of hepatoblastoma at the age of 2. The rate of birth defects in perinatal period was higher in ICSI children of multiple pregnancies than in the general population (P＜0.05). The body weight and body length/height of most ICSI children had obtained the standard range between 1 to 3 year-olds. Conclusion The higher rates of perinatal complications in ICSI children were closely related to multiple pregnancies.

siRNAs targetting sphingomyelin phosphodiesterase 1 protect mouse oocytes from apoptosis / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the potential of siRNAs targeting sphingomyelin phosphodiesterase 1 (SMPD1) in protecting the oocytes from apoptosis, and explore new approaches to female fertility preservation.</p><p><b>METHODS</b>Chemically synthesized siRNA targeting SMPD1 were introduced into mouse oocytes retrieved by hyperstimulation, and the cell apoptosis was analyzed by comic assay 48 and 72 h later.</p><p><b>RESULTS</b>In the oocytes without any siRNA injection, oocyte DNA damage occurred after 24 h, and large amount of DNA fragments migrated from the cells 48 h later. In oocytes injected with siRNA003, DNA migration decreased significantly as compared with the control and the other two groups injected with siRNA001 and siRNA002 (P<0.01).</p><p><b>CONCLUSION</b>siRNA targeting SMPD1 may protect the oocytes from apoptosis, and has the potential for use in future female fertility preservation.</p>

Modified vitrification method for cryopreservation of human ovarian tissues / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Vitrification is a prospective technology in ovarian tissue cryopreservation, but it is still in an initial stage. This study was conducted to investigate a modified vitrification protocol for human ovarian tissue, which can be used as an alternative to preserve fertility for young women with cancer who have to undergo cytotoxic therapy and sterilization.</p><p><b>METHODS</b>Ovarian tissue samples were collected from 15 patients and randomly allocated to groups of fresh, vitrification, and conventional slow freezing. A modified carrierless vitrification method was applied. The proportion of morphologically intact follicles in fresh ovarian tissues was compared with that in warmed/thawed tissues. The initial growth of the follicles and the concentrations of estradiol and progesterone were detected to determine the viability and endocrine function of the cryopreserved tissues.</p><p><b>RESULTS</b>The proportion of morphologically intact primordial follicles in the fresh group (97.6%) was significantly higher than that in the other two groups (vitrification group 80.3% and slow-freezing group 72.6%, P < 0.001). In both the vitrification and slow-freezing groups, estradiol and progesterone were secreted continuously during 2-week culture in vitro, the proportion of primary follicles were both significantly increased compared to the fresh group. No statistically significant differences existed between the two groups after cryopreservation in the proportion of both primordial and primary follicles, and the concentrations of estradiol and progesterone (P > 0.05).</p><p><b>CONCLUSION</b>The modified vitrification method for cryopreservation of human ovarian tissues is effective, simple, and inexpensive.</p>

The clinical application of whole chromosome painting probes in preimplantation genetic diagnosis for translocation carriers / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To make preimplantation genetic diagnosis (PGD) for female translocation carriers by analyzing first polar bodies (1PBs) with whole chromosome painting probe (WCP).</p><p><b>METHODS</b>WCP was used in fluorescence in situ hybridization (FISH) analysis of 1PBs for four female Robertsonian carriers presented for PGD with 45 XX, der(13;14)(q10;q10) karyotype. All the patients underwent ovarian stimulation and during 6 h after oocyte retrieval 1PBs were biopsied and WCP were used in FISH. On day 3 after fertilization embryos diagnosed as normal or balanced were transferred.</p><p><b>RESULTS</b>A total of 61 oocytes were collected in 4 PGD cycles. Of the 54 matured oocytes, 50 were biopsied and 45 were fixed successfully. Results were obtained in 40 1PBs. Overall, 74.1% (40/54) oocytes were diagnosed. The fertilization rate and good embryo rate were 64.8% (35/54) and 65.7% (23/35) respectively. Two clinical pregnancies were obtained. One patient delivered a normal female baby with karyotype 46, XX in June 2006. For another patient, the fetus spontaneously aborted at 9th week of pregnancy with karyotype of 45, X confirmed by amniotic villus diagnosis.</p><p><b>CONCLUSION</b>WCP can differentiate normal, balanced and unbalanced oocytes accurately and can be used as an efficient PGD method for female carriers of translocation.</p>

Screening for the microdeletions of azoospermia factor on the Y chromosome in male infertile patients from Guangzhou / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between microdeletion of azoospermia factor (AZF) and male infertility.</p><p><b>METHODS</b>Multiplex PCR was used to detect Y chromosome microdeletion in AZFa, AZFb and AZFc in 103 cases of idiopathic azoospermia, 72 cases of severe idiopathic oligozoospermia, and 60 healthy male controls.</p><p><b>RESULTS</b>No microdeletion was found in 60 controls. Y chromosome microdeletion was found in 19 of 175 azoospermia patients, the total prevalence rate of microdeletion was 10.9%. There were 15 cases (11 for azoospermia, 4 for severe oligozoospermia) in AZFc (8.6%), 3 cases (1 for azoospermia, 2 for severe oligozoospermia) in AZFb+c (1.7%), 1 case (azoospermia) in AZFa+b+c (0.6%). According to statistics, the difference of microdeletion rate between two groups was significant(P < 0.01).</p><p><b>CONCLUSION</b>Y chromosome microdeletions is an important reason of azoospermia. Screening of Y chromosome microdeletions for azoospermia patients before intracytoplasmic sperm injection treatment is essential.</p>

Analysis of chromosome mosaicism in preimplantation embryos by using 2 sequential rounds of fluorescence in situ hybridization / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the mechanism and factors affecting mosaicism in human preimplantation embryos by using 2 sequential rounds of fluorescence in situ hybridization(FISH).</p><p><b>METHODS</b>Totally 51 normal fertilized embryos, which were not suitable for embryo transfer and cryopreservation, were analyzed on day 3 after fertilization by using two sequential rounds of FISH. Chromosomes 13, 16, 18, 21, 22, X and Y were analyzed.</p><p><b>RESULTS</b>Among 51 embryos, 16 (31.4%) were mosaic, 12 (23.5%) were chaotic, and the remaining were either normal (27.5%) or non-mosaic abnormal (17.6%). The incidence of mosaic embryos was related to embryo developmental stage, for the incidence of mosaicism increased from 12.5% in embryos <or= 4 cell stage to 40.0% in 5-8 cell stage embryos. The aneuploidy rate for the patients over 35 years of age was significantly higher than that of the patients under 35 years (57.1% vs 23.3%).</p><p><b>CONCLUSION</b>Mosaicism is common in human preimplantaion embryos, which may be one of the important factors affecting the success rates in IVF-ET. Most of the chromosomal abnormalities can be identified by two sequential rounds of FISH.</p>

Growth differentiation factor-9 gene expression in in vitro cultured oocytes in mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the relation between oocyte maturation and growth differentiation factor-9 (GDF-9) gene expression.</p><p><b>METHODS</b>Ovariectomy was performed in 50 Kunming female mice of 10 days old, and the preantral follicles were isolated from the ovaries and cultured in medium drops for 12 days. Oocytes and somatic cells were mechanically isolated. The oocytes cultured in vitro for 2, 4, 6, 8, 10, and 12 days constituted the in vitro cultured group and the oocytes obtained from female mice of 12, 14, 16, 18, 20, and 22 days old served as the in vivo group. Semi-quantitative RT-PCR and agar gel electrophoresis were performed to quantify GDF-9 gene expression in each oocyte.</p><p><b>RESULTS</b>Follicle survival, antrum formation and maturation rate was 89.5%, 51.8% and 56.6% in the in vitro cultured follicles, respectively. GDF-9 gene expression on days 2, 4, 6, 8, 10, and 12 in in vitro cultured oocytes was 0.83-/+0.08, 0.52-/+0.09, 0.45-/+0.13, 0.49-/+0.09, 0.49-/+0.09, and 0.68-/+0.08, respectively; GDF-9 gene expression in in vivo grown oocytes of 12, 14, 16, 18, 20, and 22 days were 0.64-/+0.35, 0.48-/+0.10, 0.52-/+0.10, 0.66-/+0.08, 0.72-/+0.09, and 0.91-/+0.11, respectively. Between days 8 and 12, GDF-9 gene expression in in vitro cultured oocyte was significantly lower than that in in vivo grown oocytes (P<0.05).</p><p><b>CONCLUSION</b>MII oocytes can be obtained from in vitro culture of the preantral follicles. GDF-9 gene expression in the oocytes varies with their growth stages. Between days 8 and 12 of in vitro culture, GDF-9 gene expression in the cultured oocytes is different from that in in vivo grown oocytes.</p>

Sperm sex chromosome analysis and preimplantation genetic diagnosis of patients with sex chromosome anomalies / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the constitution of abnormal spermatozoa from patients with sex chromosome anomalies.</p><p><b>METHODS</b>Triple color fluorescence in situ hybridization (FISH) was used to determine the sex chromosome constitution of spermatozoa from three patients with sex chromosome anomalies (case 1:46,XY/47,XXY, case 2:45,XO/46,X,Yqh-, case 3:47,XXY). The preimplantation genetic diagnosis (PGD) was performed to case 2.</p><p><b>RESULTS</b>An increased ratio (2.05 vs 1) of X-bearing to Y-bearing spermatozoa was only observed in case 2, who also had an increased incidence of total abnormal spermatozoa (29.71%). An increased incidence of total abnormal spermatozoa (4.91%) was also observed in case 3. Among the constitution of abnormal spermatozoa, case 2 had the increased proportions of XY18 disomy, O18 monosomy and XO monosomy, while case 3 had an increase proportion of XY18 disomy (1.87%). PGD was performed to case 2 and one embryo with XX1818 was selected for implanting.</p><p><b>CONCLUSION</b>Using FISH to detect the sperm sex chromosomes in patients with sex chromosome anomalies can provide the useful information to evaluate the risk of sex chromosome anomalies in preimplantation embryos.</p>

Clinical analysis of intracytoplasmic sperm injection in patients with previous fertilization failure after conventional IVF / 中华男科学杂志

<p><b>OBJECTIVE</b>To analyze the clinical outcome of intracytoplasmic sperm injection (ICSI) in patients with previous fertilization failure after conventional IVF.</p><p><b>METHODS</b>Data from 20 ICSI cases (22 ICSI cycles) with previous complete failure of fertilization or with fertilization rate < or = 20% between January 2002 and December 2004 were retrospectively analyzed. The control group consisted of 100 consecutive ICSI cycles for male factor infertility in the same period.</p><p><b>RESULTS</b>The fertilization rate dramatically increased from 5.4% after conventional IVF to 76.9% after ICSI treatment (chi-squared = 264.66, P < 0.001). However, the fertilization rate in the subgroup with previous low fertilization was significantly lower than those in the control and in the subgroup without previous fertilization (67.9% vs 77.5%, 67.9% vs 84.2%). Compared with the control group, the subgroup without previous fertilization had a higher pregnancy rate and implantation rate, but only the difference in the implantation rate was statistically significant (40.5% vs 18.9%).</p><p><b>CONCLUSION</b>ICSI can overcome previous fertilization failure with conventional in vitro fertilization and thus improve the clinical outcome.</p>

Establishment of human embryonic stem cell line from gamete donors / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human embryonic stem (HES) cell derived from human blastocyst can be propagated indefinitely in the primitive undifferentiated state while remaining pluripotent. It has exciting potential in human developmental biology, drug discovery, and transplantation medicine. But there are insufficient HES cell lines for further study.</p><p><b>METHODS</b>Three oocyte donors were studied, and 3 in vitro fertilization (IVF) cycles were carried out to get blastocysts for the establishment of HES cell line. Isolated from blastocysts immunosurgically, inner cell mass (ICM) was cultured and propagated on mouse embryonic fibroblasts (MEFs). Once established, morphology, cell surface markers, karyotype and differentiating ability of the cell line were thoroughly analyzed.</p><p><b>RESULTS</b>Four ICMs from 7 blastocysts were cultured on MEFs. After culture, one cell line (cHES-1) was established and met the criteria for defining human pluripotent stem cells including a series of markers used to identify pluripotent stem cells, morphological similarity to primate embryonic stem cells and HES reported else where. Normal and stable karyotype maintained over 60 passages, and demonstrated ability to differentiate into a wide variety of cell types.</p><p><b>CONCLUSIONS</b>HES cell lines can be established from gamete donors at a relatively highly efficient rate. The establishment will exert a widespread impact on biomedical research.</p>

Closely linked polymorphic marker: successful application in preimplantation genetic diagnosis for beta-thalassemia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To evaluate the applicability of the polymorphic marker closely linked with beta-globin gene for the preimplantation genetic diagnosis (PGD) in couples at risk of having child with beta-thalassemia.</p><p><b>METHODS</b>Single cell multiplex nested PCR which coamplifies the beta-globin gene and the closely linked polymorphic marker, HumTHO1 gene, was applied in six clinical PGD cycles for four couples with beta-thalassemia.</p><p><b>RESULTS</b>In six clinical PGD cycles, a total of 44 embryos were biopsied and 44 blastomeres were obtained. Forty-one blastomeres were amplified and thirty-five embryos were given definite diagnoses. Fourteen embryos were transferred back to the uterus of the patients and one pregnancy went on well and ended with one live healthy birth, which confirmed the results of PGD. The average amplification efficiency of single blastomere was 89.7% and the average allele drop-out(ADO) rate was 14.4%. The coamplification of HumTHO1 could help to detect the existence of ADO and contamination.</p><p><b>CONCLUSION</b>This is the first report on unaffected pregnancy resulting from PGD using multiplex nested PCR in China. The simultaneous amplification of polymorphic marker closely linked to beta-globin gene(HumTHO1) could help to resist the risk of misdiagnosis in PGD caused by ADO and contamination.</p>

Birth of healthy children after preimplantation diagnosis of beta-thalassemia / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Clinical programs for preventing beta-thalassemia are presently based on prospective carrier screening and prenatal diagnosis. This paper report an achievement of a pregnancy with unaffected embryos using in vitro fertilization and embryo transfer (IVF-ET), in combination with preimplantation genetic diagnosis (PGD), for a couple at risk of having children with beta-thalassemia.</p><p><b>METHODS</b>A couple carrying different thalassemia mutations, both a codon 41 - 42 mutation and the IVS II 654 mutation, received standard IVF treatment, with intracytoplasmic sperm injection, embryo biopsiy, single cell polymerase chain reaction (PCR) and DNA analysis. Only unaffected or carrier embryos were transferred to the uterine cavity. After confirmation of pregnancy, a prenatal diagnosis was performed.</p><p><b>RESULTS</b>Of a total of 13 embryos analyzed for beta-globin mutations, PGD indicated that 2 were normal, 3 were affected, and 6 were carriers. Diagnosis could not be made in the other 2 embryos. Three embryos were transferred to the uterus on the third day after oocyte retrieval. Ultrasonography revealed a twin pregnancy with one blighted ovum. The prenatal genetic diagnosis revealed that both fetuses were unaffected, and two healthy boys were born, confirming the results of PGD.</p><p><b>CONCLUSIONS</b>We developed a single-cell based primer extension preamplification (PEP)-PCR assay for the detection of beta-thalassemia mutations. The assays were efficient and accurate at all stages of the procedure, and resulted in the birth of PGD-confirmed beta-thalassemia free children in China. PEP was used here in PGD for beta-thalassemia.</p>

Cryopreservation of human embryonic stem cells by vitrification / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The efficiency of traditional cryopreservation of human embryonic stem (ES) cells is low, and there have been few attempts to prove new cryopreservation methods effective. This study was designed to evaluate the efficiency of cryopreservation of human ES cells using vitrification method.</p><p><b>METHODS</b>Human ES cells clumped from an identical cell line were randomly allocated to be cryopreserved by vitrification or by slow freezing. The recovery rates, the growth and differentiation potential of thawed human ES cells were compared between these two groups. The pluripotency of human ES cells after thawing was identified.</p><p><b>RESULTS</b>Eighty-one point nine percent (59/72) of human ES cell clumps were recovered after vitrification, while only 22.8% (16/70) were recovered after slow freezing (P < 0.01). The colonies after vitrification manifested have not only faster growth but also a lower level of differentiation when compared to colonies subjected to the slow freezing protocol. However, the rates of growth and differentiation in undifferentiated colonies from both groups were identical to the rates in those of non-cryopreserved stem cells after a prolonged culture period. Passage 6 of vitrified human ES cells retained the properties of pluripotent cells, a normal karyotype and expressed the transcription factor OCT-4, stage specific expressed antigen-4 (SSEA-4) and SSEA-3. Teratoma growth of these cells demonstrated the ability to develop into all three germ layers.</p><p><b>CONCLUSIONS</b>Vitrification is effective in cryopreserving human ES cells. During a prolonged culture, human ES cells retain their pluripotency after cryopreservation.</p>

Single cell analysis of some deletion in dystrophin gene exons and gender determination by 3-plex nested PCR / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To set up a technique of single lymphocytes 3-plex nested PCR for dystrophin and SRY gene, and to evaluate the possibility of using this technique for preimplantation genetic diagnosis(PGD) of deleted Duchenne muscular dystrophy (DMD) with family history.</p><p><b>METHODS</b>Fifty single lymphocytes of a normal male and fifty of a normal female were obtained for detecting dystrophin gene(exon 51, exon 19, exon 48) and SRY gene by 3-plex nested PCR.</p><p><b>RESULTS</b>In the group of exon 51/exon 19/SRY, the amplification rates of exon 51, exon 19 and SRY in male were 96%, 94% and 94%; the amplification rates of exon 51 and exon19 in female were 94% and 94%, respectively. In the exon 48/exon 19/SRY group, the amplification rates of exon 48, exon 19 and SRY in male were 92%, 90% and 94%, the amplification rates of exon 48, exon 19 in female were 94% and 92%, respectively.</p><p><b>CONCLUSION</b>The technique of single lymphocytes 3-plex nested PCR for dystrophin and SRY gene established in this study is highly sensitive, specific and reliable, and is suitable for PGD of deleted DMD with family history.</p>