Complexant-montmorillonite nanocomposites were successfully prepared through the intercalation of the complexants cysteamine hydrochloride (CSH), 1,6-diaminlhexane (DA), tetraethylenepentamine (TEPA) ...with different functional group and molecular weight in this work. More importantly, it was proved that the heavy metal stabilization property of montmorillonite improved significantly after intercalation of complexants through characterization by XRD and SEM-EDS. Here, the complexant-montmorillonite nanocomposites exhibited strong pH buffering effects. The Zn stabilization rate was prone to 100% by adding DA or TEPA modified montmorillonite (DA-Mt or TEPA-Mt) into the tailings, and the releasing rate of As and Mn from tailings also decreased greatly. Generally, the Zn, Pb, Mn and As stabilization effects of both TEPA-Mt and DA-Mt were much better than that of CSH modified montmorillonite, which suggested that the heavy metal complexing abilities of complexant-montmorillonite nanocomposites highly depended on the functional group and molecular weight of the complexants. In this study, electrostatic adsorption, physical adsorption, ion exchange and complexation worked together and produced good heavy metal stabilization effect. Our findings could provide an important reference for the synthesis of efficient stabilization nanomaterials.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The aim of this study was to explore factors contribute to the success of PGD cycles for monogenic diseases.
During a 3-year period (January 2009 to December 2012), 184 consecutive ICSI-PGD cycles ...for monogenic diseases reaching the ovum pick-up and fresh embryo-transfer stage performed at the Reproductive Medicine Center of The First Affiliated Hospital Of Sun Yat-sen University were evaluated.
ICSI was performed on 2206 metaphase II oocytes, and normal fertilization and cleavage rates were 83.4% (1840/2206) and 96.2% (1770/1840), respectively. In the present study, 60.5% (181/299) of day 3 good-quality embryos developed into good-quality embryos on day 4 after biopsy. Collectively, 42.9% clinical pregnancy rate (79/184) and 28.5% implantation rate (111/389) were presented. In the adjusted linear regression model, the only two significant factors affecting the number of genetically unaffected embryos were the number of biopsied embryos (coefficient: 0.390, 95%CI 0.317-0.463, P = 0.000) and basal FSH level (coefficient: 0.198, 95%CI 0.031-0.365, P = 0.021). In the adjusted binary logistic regression model, the only two significant factors affecting pregnancy outcome were the number of genetically available transferable embryos after PGD (adjusted OR 1.345, 95% CI 1.148-1.575, P = 0.000) and number of oocyte retrieved (adjusted OR 0.934, 95% CI 0.877-0.994, P = 0.031).
There should be at least four biopsied embryos to obtain at least one unaffected embryos in a PGD system for patients with single gene disorder and under the condition of basal FSH level smaller than 8.0mmol/L. Moreover, if only a low number (< 4) of biopsied embryos are available on day 3, the chance of unaffected embryos for transfer was small, with poor outcome.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background:
Preimplantation genetic test for monogenic disorders (PGT-M) has been used to select genetic disease-free embryos for implantation during
in vitro
fertilization (IVF) treatment. However, ...embryos tested by PGT-M have risks of harboring chromosomal aneuploidy. Hence, a universal method to detect monogenic diseases and genomic imbalances is required.
Methods:
Here, we report a novel PGT-A/M procedure allowing simultaneous detection of monogenic diseases and genomic imbalances in one experiment. Library was prepared in a special way that multiplex polymerase chain reaction (PCR) was integrated into the process of whole genome amplification. The resulting library was used for one-step low-pass whole genome sequencing (WGS) and high-depth target enrichment sequencing (TES).
Results:
The TAGs-seq PGT-A/M was first validated with genomic DNA (gDNA) and the multiple displacement amplification (MDA) products of a cell line. Over 90% of sequencing reads covered the whole-genome region with around 0.3–0.4 × depth, while around 5.4%–7.3% of reads covered target genes with >10000 × depth. Then, for clinical validation, 54 embryos from 8 women receiving PGT-M of β-thalassemia were tested by the TAGs-seq PGT-A/M. In each embryo, an average of 20.0 million reads with 0.3 × depth of the whole-genome region was analyzed for genomic imbalance, while an average of 0.9 million reads with 11260.0 × depth of the target gene
HBB
were analyzed for β-thalassemia. Eventually, 18 embryos were identified with genomic imbalance with 81.1% consistency to karyomapping results. 10 embryos contained β-thalassemia with 100% consistency to conventional PGT-M method.
Conclusion:
TAGs-seq PGT-A/M simultaneously detected genomic imbalance and monogenic disease in embryos without dramatic increase of sequencing data output.
Technological innovation and high-quality economic development are inevitable requirements of sustainable development, and the digital economy has gradually become a new engine to enhance ...technological innovation and the high-quality development of China’s economy. Deeply discussing the effect of digital economy on high-quality economic development and clarifying the mechanism behind it can effectively grant the boosting power of digital economy to China’s high-quality development, which is of great practical significance to China’s sustainable economic development. In this study, the mechanism, effect, and regional heterogeneity of the impact of the digital economy on the level of high-quality economic development in 30 Chinese provinces from 2011–2019 were measured and empirically tested using a mediating effects model and a spatial Durbin model, among others. The results showed that the overall level of digital economy and high-quality development is not high, and there were both high agglomeration and low agglomeration, with obvious spatial path dependence and spatial lock-in. Digital economy could promote the high-quality development level of the economy, and the spatial spillover effect was remarkable. In addition, the function of digital economy in promoting high-quality economic development in the eastern, central, and western regions was gradually weakened. Besides, the technological innovation was an important transmission path of digital economy to high-quality economic development. Based on these findings, it is proposed that decision-makers should strengthen digitalization efforts so that the digital economy can become a powerful tool to narrow the digital divide. Further, the dynamic and differentiated digital economy development strategy should be implemented to reduce regional development imbalances in an effective manner.
Hatching is crucial for mammalian embryo implantation, since difficulties during this process can lead to implantation failure, ectopic pregnancy and consequent infertility. Despite years of ...intensive researches, how internal and external factors affecting embryo hatch are still largely unclear.
The effects of parental genetic material and oxygen concentration on hatch process were examined. Fertilized and parthenogenetic mouse preimplantation embryos were cultured in vitro under 5 and 20% oxygen for 120 h. Zona pellucida drilling by Peizo micromanipulation were performed to resemble the breach by sperm penetration.
Firstly, parthenogenetic embryos had similarly high blastocyst developmental efficiency as fertilized embryos, but significantly higher hatch ratio than fertilized embryos in both O
concentrations. 5% O
reduced the hatch rate of fertilized embryos from 58.2 to 23.8%, but increased that of parthenogenetic embryos from 81.2 to 90.8% significantly. Analogously, 5% O
decreased the ratio of Oct4-positive cells in fertilized blastocysts, whereas increased that in parthenogenetic blastocysts. Additionally, 5% O
increased the total embryonic cell number in both fertilized and parthegenetic embryos, when compared to 20% O
, and the total cell number of fertilized embryos was also higher than that of parthegenetic embryos, despite O
concentration. Real-time PCR revealed that the expression of key genes involving in MAPK pathway and superoxide dismutase family might contribute to preimplantation development and consequent blastocyst hatch in vitro. Finally, we showed that fertilized and parthenogenetic embryos have diverse hatch dynamics in vitro, although the zona pellucida integrity is not the main reason for their mechanistic differences.
Both parental genetic material and O
concentration, as the representative of intrinsic and extrinsic factors respectively, have significant impacts on mouse preimplantation development and subsequent hatch dynamics, probably by regulating the gene expression involving in MAPK pathway and superoxide dismutase family to control embryonic cell proliferation and allocation of ICM cells.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Neurofibroma type 1 (NFI) is an autosomal dominant genetic disease associated with cancer and cognitive dysfunction. The 50% de novo mutation rate and numerous mutation types of the
NF1
gene pose ...challenges to preimplantation genetic testing (PGT) for NFI. In 2020, a couple was subjected to next-generation sequencing (NGS)-based PGT at our center. Both husband and wife carried de novo
NF1
mutations. Biopsied trophectoderm samples underwent whole-genome amplification using multiple displacement amplification. NGS was conducted to detect
NF1
mutations as well as 105 closely linked single-nucleotide polymorphisms (SNPs) flanking
NF1
. Since no affected family member was available, the affected embryos identified by
NF1
-targeted sequencing were assigned as probands, based on which a haplotype analysis was constructed with informative SNP sites. Sanger sequencing was administrated for verification. Aneuploidy screening through NGS was performed in the same PGT cycle. Finally, among the nine biopsied blastocysts, two unaffected and euploid blastocysts were obtained in the couple, and one of the blastocysts was transferred in a frozen–thawed embryo transfer (FET) cycle. The outcome of FET is under observation. This study is the first to apply NGS-based PGT for NFI. In cases of sporadic NFI cases without affected family members, NGS-SNP can perform haploid analysis in an accurate manner by assigning the affected embryos as probands.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
Constructing crystalline covalent organic frameworks (COF) robust 3D reusable macroscopic objects exposing more adsorption sites with high water flux for use as a filter is an unresolved ...challenge. A simple scalable procedure is shown for making a robust, highly compressible 3D crystalline COF nanowire interconnected porous open‐cell sponge. The compressive strength and Young's modulus (80% strain) of the sponge are 175 and 238 kPa, respectively. The sponge can withstand multiple compression‐release cycles and a load of 2800 times its weight without collapsing. As an exemplary application, the use of a COF sponge in the selective removal and separation of cationic model dye from a mixture of dyes in water by adsorption and filtration with >99% efficiency is shown. Depending on the dye concentration, the dye removal time can be as short as 2 min, and dye adsorption efficiency can be as high as 653 mg g
−1
(COF in the sponge). During filtration, the sponges as filters show a high water flux of 2355 L h
−1
m
−2
under ambient conditions and maintain their performance for many cycles. The lightweight, reusability, and efficiency make present sponges sustainable materials as adsorbents and filters.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Even though it generates healthy adults, nuclear transfer in mammals remains an inefficient process. Mainly attributed to abnormal reprograming of the donor chromatin, this inefficiency may also be ...caused at least partly by a specific effect of the cloning technique which has not yet been well investigated. There are two main procedures for transferring nuclei into enucleated oocytes: fusion and piezoelectric microinjection, the latter being used mostly in mice. We have, therefore, decided to compare the quality and the developmental ability, both in vivo and in vitro, of embryos reconstructed with electrofusion or piezoelectric injection. In addition, the effect of piezo setups of differing electric strengths was investigated. Along with the record of the rate of development, we compared the nuclear integrity in the blastomeres during the first cleavages as well as the morphological and cellular quality of the blastocysts. Our results show that the piezo-assisted micromanipulation can induce DNA damage in the reconstructed embryos, apoptosis, and reduced cell numbers in blastocysts as well as a lower rate of development to term. Even if piezo-driven injection facilitates a faster and more efficient rate of reconstruction, it should be used with precaution and with as low parameters as possible.
To completely avoid ice crystal formation and thus get a higher survival rate, vitrification methods have been commonly used for cryopreservation of oocytes and embryos. However, currently used ...vitrification methods for oocytes and embryos are not suitable for the cryopreservation of preantral follicles (PFs). In the present study, stainless steel mesh was fabricated into mini mesh cups to vitrify isolated PFs. Moreover, isolated follicles were encapsulated and then subjected to vitreous cryopreservation to facilitate in vitro culture/maturation of follicles after warming. The results showed that the percentages of viable follicles did not differ significantly between the vitrification group and fresh group soon after warming (81.25% vs. 85.29%, P>0.05) and after a 7-day culture period (77.78% vs. 83.33%, P>0.05). No difference in mean follicular diameter was observed between cryopreserved and fresh follicles when cultured in vitro. Transmission electron microscopic analysis revealed that vitreous cryopreservation could maintain the ultrastructure of follicles in alginate beads. In conclusion, the present vitrification method could efficiently cryopreserve isolated human ovarian follicles encapsulated by calcium alginate, which could be put into immediate use (in vitro culture/ maturation) after warming. However, more follicles and some detailed biochemical analyses are required to further investigate the effects of vitrification on the long-term growth of human encapsulated PFs.
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