The Impact of Cryopreservation-Thawing Conditions on Umbilical Cord Blood Quality and Transplantation Outcomes

BACKGROUND

Cord blood units (CBUs) go through the cryopreservation-thawing process for storage before use in transplantation. The differences in the cryopreservation-thawing process affect the quality of CBUs. The effects of the cryopreservation-thawing process on the final outcomes of CBU transplantation has not been defined well.

OBJECTIVE

To study the impact of differences in the cryopreservation-thawing process on the quality of CBUs and the final clinical outcomes of transplantation.

MATERIALS AND METHODS

The differences in cryopreservation-thawing conditions were analyzed to determine their effect on the quality and clinical outcomes of transplanted CBUs. CBUs were detected using the same reagents, instruments and methods for minimizing experimental errors.

RESULTS

The differences in the cryopreservation-thawing process did not change cell survival, TNCC recovery (CD34⁺ and CFUs), the implantation rates and recovery time of neutrophils/100-day platelets.

CONCLUSION

The present study shows that the differences in the cryopreservation-thawing conditions do not influence the quality and transplantation outcomes of CBUs.

[Chorionic villus cell culture and karyotype analysis in 1 983 cases of spontaneous miscarriage]

Objective: To investigate the relationship between spontaneous miscarriage and embryonic chromosome abnormalities, and to evaluate the clinical application of karyotype analysis by chorionic villus cell culture. Methods: The chorionic villus karyotype of 1 983 cases of miscarriage from January 2010 to July 2016 in Guangzhou Women and Children's Mecical Center were analyzed retrospectively. The miscarried chorionic villi were obtained by curettage under sterilized condition. The chromosome specimens were prepared after chorionic villus cell culture. Karyotype analysis was performed by G-banding technique. Results: In the 1 983 samples, successful karyotype analysis was performed in 1 770 cases, with the successful rate of 89.98%. Chromosomal abnormalities were found in 1 038 cases (58.64%, 1 038/1 770). Chromosomal structural abnormalities were found in 37 cases. The numeral abnormalities were more common than structural abnormalities, and most of the numeral abnormalities were aneupoidies. In turn, they were trisomy 16, 45,X, trisomy 22, trisomy 2, trisomy 21, trisomy 15. The most common structural abnormality was balanced translocation, including Robersonian translocation. Female embryoes accounted for 61.02% (1 080/1 770) miscarriages and for 57.4%(596/1 770) of chromosomal abnormalities, while male embroyes acoounted for 61.02% (1 080/1 770) , 57.4% (596/1 770) respectively. The proportion of female embryoes was higher than male embryoes. The median age of the patients was 30 years old (16-46 years old) . As the maternal age increased, the proportion chromosomal abnormalities increased. The incidence of chromosomal abnormalities in the advanced age group (≥35 years) was 68.38% (240/351) , which was significantly higher than that in the younger group (56.24%, 798/1 419; χ(2)=17.10, P<0.01). Conclusions: Embryonic chromosomal abnormalities are the most common cause of early spontaneous miscarriage. The abnormalities centralize in some karyotypes. There is certain relationship between maternal age and the incidence of miscarriage, as well as the embryonic gender. Chorionic villus cell culture and karyotype analysis are helpful in finding the cause of miscarriage and counsel the patients.

Resting-State Functional MRI: Everything That Nonexperts Have Always Wanted to Know

Resting-state fMRI was first described by Biswal et al in 1995 and has since then been widely used in both healthy subjects and patients with various neurologic, neurosurgical, and psychiatric disorders. As opposed to paradigm- or task-based functional MR imaging, resting-state fMRI does not require subjects to perform any specific task. The low-frequency oscillations of the resting-state fMRI signal have been shown to relate to the spontaneous neural activity. There are many ways to analyze resting-state fMRI data. In this review article, we will briefly describe a few of these and highlight the advantages and limitations of each. This description is to facilitate the adoption and use of resting-state fMRI in the clinical setting, helping neuroradiologists become familiar with these techniques and applying them for the care of patients with neurologic and psychiatric diseases.

Lapine periodontal ligament stem cells for musculoskeletal research in preclinical animal trials

Background

Human periodontal ligament stem cells (hPDLSCs) have been shown to be a reliable source of mesenchymal stem cells (MSCs). On the other hand, rabbits have been commonly used in preclinical trials for musculoskeletal research. However, there is a lack of sufficient data on using rabbit periodontal ligament stem cells (rPDLSCs) for regenerative dentistry. This study, for the first time, comprehensively compared rPDLSCs against hPDLSCs in terms of clonogenicity, growth potential, multi-differential capacity and surface antigens.

Methods

Periodontal ligament (PDL) was obtained from the rabbit and human teeth. rPDL and hPDL cells were isolated from PDL using enzymatic digestion method. After culturing for 2 weeks, the cells were first analyzed microscopically. STRO-1⁺CD146⁺ PDLSCs were then sorted from PDL cells by fluorescence-activated cell sorting (FACS) followed by examination of CD34, CD45, CD90, vimentin and desmin markers. The cells were also evaluated by immunohistocytochemical and multi-differentiation potential tests. The clonogenicity and growth of PDL cells were analyzed by Independent T test and 2-way repeated measures ANOVA respectively.

Results

rPDL cells were broader and less elongated as compared to hPDL cells. STRO-1⁺CD146⁺ hPDLSCs were isolated from hPDL cells but not from the rPDL cells. Therefore, heterogeneous population of rabbit and human PDL cells were subsequently used for latter comparative studies. FACS analysis and immunohistocytochemistry revealed that rPDL cells were partially positive for STRO-1 as compared to hPDL cells. Furthermore, both rPDL cells and hPDL cells were positive for CD146, CD90, vimentin, and desmin, while negative for CD34 and CD45. No difference in clonogenicity between rPDL and hPDL cells was found (p > 0.05). The proliferative potential of rPDL cells displayed significantly slower growth as compared to hPDL cells (p < 0.05). Osteogenic, adipogenic, and chondrogenic differentiation potential was comparatively less in rPDL cells than that of hPDL cells, but the neurogenic differential potential was similar.

Conclusion

Although rPDL cells manifested variable differences in expression of stem cell markers and multi-differential potential as compared to hPDL cells, they demonstrated the attributes of stemness. Further studies are also required to validate if the regenerative potential of rPDL cells is similar to rPDLSCs.

Whole exome sequencing as a diagnostic adjunct to clinical testing in fetuses with structural abnormalities

OBJECTIVES

To evaluate the diagnostic yield of prenatal whole exome sequencing (WES) for monogenic disorders in fetuses with structural malformations and normal results on cytogenetic testing, and to describe information on pathogenic variants that is provided by WES.

METHODS

Karyotyping, chromosomal microarray analysis (CMA) and WES were performed sequentially on stored samples from a cohort of 3949 pregnancies with fetal structural abnormalities detected on ultrasound and/or magnetic resonance imaging, referred between January 2011 and December 2015. Diagnostic rates of the three techniques were investigated overall, for phenotypic subgroups and for proband-only vs fetus-mother-father samples. Information on pathogenic variants was identified by WES.

RESULTS

Overall, 18.2% (720/3949) of fetuses had an abnormal karyotype. Pathogenic copy number variants were detected on CMA in 8.2% (138/1680) of fetuses that had a normal karyotype result. WES performed on a subgroup of 196 fetuses with normal CMA and karyotype results revealed the putative genetic variants responsible for the abnormal phenotypes in 47 cases (24%). The molecular diagnosis rates for fetus-mother-father and proband-only samples were 26.5% (13/49) and 23.1% (34/147), respectively. Variants of uncertain significance were detected in 12.8% (25/196) of fetuses, of which 22 were identified in the fetal proband-only group (15%; 22/147) and three in the fetus-mother-father group (6.1%; 3/49). The incidental finding rate was 6.1% (12/196).

CONCLUSIONS

WES is a promising method for the identification of genetic variants that cause structural abnormalities in fetuses with normal results on karyotyping and CMA. This enhanced diagnostic yield has the potential to improve the clinical management of pregnancies and to inform better the reproductive decisions of affected families. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

[Application of chromosomal microarray analysis for fetuses with talipes equinovarus]

OBJECTIVE

To investigate the application of fetuses with talipes equinovarus(TE)using chromosomal microarray analysis(CMA)technology.

METHODS

From May 2012 to June 2015, 54 fetuses were found with TE and with or without other structural anomalies by prenatal ultrasound. Karyotyping was taking for them all, and the fetuses with normal karyotypes took another CMA test. The data were analyzed with CHAS software. Finally all the cases were followed up to know about their pregnancy outcomes.

RESULTS

One of the 54 cases was detected with abnormal karyotype which was trisomy 18(2%, 1/54). CMA was undertaken to the remaining fetuses, they were divided into 2 groups, including isolated TE group(n= 38)and complex TE group(n=15). The detection rate of clinical significant copy number variations(CNV)by CMA was 11%(6/53), while isolated and complex TE group were 5%(2/38)and 4/15, respectively(P= 0.047). Of the 53 cases, 51 cases were successfully followed up. Eleven cases were found without TE after birth, and the false positive rate(FPR)of TE was 22%(11/51).

CONCLUSIONS

Whole-genome high-resolution CMA increased the detection rate by 11% in fetuses with TE. With the FPR and the detection rate of the clinical significant CNV of 2 groups, whole-genome CMA could be recommended to the fetuses with complex TE group but normal karyotypes. A series of ultrasonic tests should be suggested to the isolate TE group, while with the abnormal ultrasound, fetuses would be suggested to have CMA test for decreasing the rates of invasive prenatal diagnosis and FPR.

Detection of fetal copy number variants by non-invasive prenatal testing for common aneuploidies

OBJECTIVE

To evaluate the clinical performance of non-invasive prenatal testing (NIPT) in detecting fetal copy number variants (CNVs).

METHODS

NIPT of cell-free fetal DNA was performed retrospectively, using stored maternal plasma, at an average gestational age of 21.1 weeks in 117 pregnant women who had previously undergone invasive prenatal testing for chromosome microarray analysis (CMA). Among the fetal samples tested by CMA, 18 had positive results (CNVs > 1 megabase (Mb)) and 99 had negative results (CNVs < 1 Mb or without CNVs detected). The results of NIPT and CMA were then compared.

RESULTS

In the 11 CMA-positive samples with CNVs > 5 Mb, the detection rate of CNVs was 90.9%; the one case missed by NIPT had a fetal fraction of 4.7%. For the other seven CMA-positive samples with CNVs < 5 Mb, the detection rate was 14.3%; only one case with a 2.82-Mb duplication was detected, with a fetal fraction of 26.7%. For 35.7% (5/14) of CNVs detected by both NIPT and CMA, the differences in fragment length were within ± 1 Mb. In this study, the overall sensitivity and specificity of NIPT for detecting CNVs > 1 Mb were 61.1% and 95.0%, respectively, with a false-positive rate of 5.0%.

CONCLUSIONS

Our results demonstrate that NIPT for common aneuploidies can detect fetal CNVs > 5 Mb with high sensitivity, provided that fetal fraction is high enough, without increasing sequencing depth. The detection power of NIPT is determined mostly by fetal fraction and CNV size. A positive NIPT screening result for CNVs must be interpreted with caution and validated by additional diagnostic study.

Uptake of non-invasive prenatal testing in Chinese women: money matters

OBJECTIVE

To determine the influence of free invasive prenatal testing on the uptake of non-invasive prenatal testing (NIPT).

STUDY DESIGN

Over a 2-year period at a Chinese tertiary prenatal diagnostic unit, women at risk of fetal trisomy were given the option of NIPT or invasive prenatal testing. Invasive prenatal testing was offered free of charge to women with a local Hukou (household registration); however, women without a local Hukou were charged for invasive prenatal testing. Both women with and without a local Hukou were charged for NIPT.

RESULTS

During the first year, 2647 women with a positive trisomy 21 screening test were referred (474 women with a local Hukou and 2173 women without a local Hukou). Only 1.6% of the women with a local Hukou underwent NIPT, while this proportion was 20.6% in the women without a local Hukou. During the second year, the price of NIPT was reduced. The total number of women referred was 3047 (502 women with a local Hukou and 2545 women without a local Hukou). The uptake of NIPT in women without a local Hukou doubled, but the uptake of NIPT remained stable in women with a local Hukou.

CONCLUSION

The financial impact on the uptake of NIPT should not be underestimated.