Search

A farmland drought remote sensing dynamic monitoring system has been established on the Android mobile platform in order to meet the actual needs of users for observation of agricultural conditions such as farmland drought. For the problem of inefficiency in traditional manual field recording by user, the system combines the advantages of portable mobile devices and global positioning system (GPS) to realize the digital management of farmland data, and completes a set of proceesing flow from field data entry, processing to export. With the purpose of real - time drought dynamic monitoring, the system uses the massive remote sensing data management and powerful calculating ability advantages provided by the Google Earth Engine remote sensing cloud computing platform, utilizes multi - source remote sensing data such as Landsat, MODIS and Sentinel, applies the Flask framework to implement the Google Earth Engine platform Python service interface access scheme, and completes the function of dynamic drought monitoring for farmland, which provides users with a technical application platform for selecting the remote sensing data source, calculating the drought monitoring model and finally generating the grade thematic map of drought. [ABSTRACT FROM AUTHOR]

Objective: To assess the value of copy number variation sequencing (CNV-seq) and karyotyping in the prenatal diagnosis for carriers of balanced translocations., Methods: Clinical records of 135 amniocentesis samples of balanced translocation carriers undergoing simultaneous CNV-seq and karyotyping were analyzed. Chromosomal aberrations were defined as those can definitely lead to birth defects definitely, which included chromosomal numerical abnormality, large deletion/duplication and pathogenic copy number variations (pCNVs)., Results: The detection rates for karyotyping and CNV-seq were 4.44% (6/135) and 5.93% (8/135) respectively, and the latter had a detection rate of 1.48(2/135) higher than the former. A total of 68 fetal chromosomal translocations were detected by karyotying analysis., Conclusion: For couples carrying a balanced translocation, simultaneous CNV-seq and karyotyping is conducive to the detection of fetal chromosomal abnormalities and genetic counseling.

Objective: To explore the genetic basis of three families with recurrence of non-immune hydrops fetalis (NIHF) but negative result by copy number variation sequencing (CNV-seq)., Methods: Amniotic fluid sample and/or abortive tissues of the fetuses were collected and subjected to CNV-seq analysis. Peripheral blood samples of the parents were also taken for trio whole exome sequencing (trio WES)., Results: Fetus 1 was found to harbor heterozygous c.976G>T(p.Glu326*) variant of the SOX18 gene in addition with compound heterozygous variants c.844C>T(p.Arg282Trp) and c.9472+1G>A of the RYR1 gene. The three variants were all inherited from its parents and have been associated with the etiology of NIHF. Based on the American College of Medical Genetics and Genomics (ACMG) standards and guidelines, the c.976G>T variant of SOX18 gene and c.9472+1G>A of RYR1 gene were predicted to be pathogenic (PVS1+PM2+PP3+PP4, PVS1+PM2+PP3), and c.844C>T variant of RYR1 gene to be likely pathogenic (PM1+PM2+PP3). Fetus 2 was found to harbor compound heterozygous variants c.6682C>T(p.Gln2228*) and c.4373_4383del(p.Val1458Alafs*63) of the PIEZO1 gene. Both variants were also inherited from its parents and are associated with the etiology of NIHF. Based on ACMG standards and guidelines, both c.6682C>T and c.4373_4383del variants of PIEZO1 gene were predicted to be pathogenic (PVS1+PM2+PP4, PVS1+PM2). Fetus 3 was found to harbor compound heterozygous variants of the TTN gene c.29860G>C(p.Asp9954His) and c.21107A>T(p.Asp7036Val), which were respectively inherited from its parents. Both variants have been strongly associated with the phenotype, though the connection between the etiology of NIHF and variants of the TTN gene remains elusive. Based on ACMG standards and guidelines, the c.29860G>C and c.21107A>T variants of TTN gene were predicted to be likely pathogenic (PM1+PM2+PP3)., Conclusion: Trio WES can improve the diagnosis rate of NIHF with a negative result by CNV-seq. Considering the urgency of prenatal diagnosis, CNV-seq and trio WES should be carried out at the same time for fetuses with NIHF.

With an incidence of 1/800 - 1/600, Down syndrome (DS) is the most common chromosomal disorder in humans. Whilst most DS patients has trisomy 21, a small proportion may carry translocations or mosaicisms involving chromosome 21. The main characteristics of DS include mental retardation, peculiar facies, growth retardation, congenital heart disease, duodenal stenosis, Alzheimer's disease, leukemia, and immunodeficiency, which may be due to increased dosage of critical genes. Recent studies also showed that epigenetic changes may also occur in DS. For research on patients with DS or other trisomies have been restricted by ethical considerations, and commonly used mouse models cannot fully replicate the characteristic features of DS, pluripotent stem cells induced from fetal samples or biopsy tissues from DS patients may generate models with the same genetic content, which may provide idea materials for studying the pathogenesis of DS and customized cell and/or gene therapies.

Mesenchymal stem cells (MSCs) have the inherent tumor-homing ability with the attraction of multiple chemokines released by tumor tissues or tumor microenvironments, which can be utilized as promising cellular carriers for targeted delivery of anti-tumor drugs and genes. In most circumstances, large amount of systemicly administrated MSCs will be firstly trapped by lungs, following with re-distribution and homing to tumor tissues after lung clearance. Several approaches like enhanced interactions between chemokines and receptors on MSCs or reducing the retention of MSCs by changes of administration methods are firstly reviewed for improving the homing of MSCs towards tumor tissues. Additionally, the potentials and gains of utilizing MSCs to carry several chemotherapeutics, such as doxorubicin, paclitaxel and gemcitabine are summarized, showing the advantages of overcoming the short half-life and poor tumor targeting of these chemotherapeutics. Moreover, the applications of MSCs to protect and deliver therapeutic genes to tumor sites for selectively tumor cells eliminating or promoting immune system are highlighted. In addition, the potentials of using MSCs for tumor-targeting delivery of diagnostic and therapeutic agents are addressed. We believed that the continuous improvement and optimization of this stem cells-based cellular delivery system will provide a novel delivery strategy and option for tumor treatment.

Objective: To analyze a family with recurrent fetal copy number variations (microdeletion and microduplication, respectively) of 1p31.1 using single nucleotide polymorphism-based array (SNP-array) and G banding chromosomal karyotyping., Methods: Amniocentesis and chorionic villus sampling were performed for a woman during the two pregnancies. Whole genome SNP-array was used to detect genomic imbalance of the fetus. The couple was also subjected to G-banding chromosomal analysis and SNP-array analysis., Results: SNP-array showed a 1p31.1 (70 164 686-83 474 843) ×1 and a 1p31.1 (70 164 686-83 479 747) ×3 in the fetuses during the two pregnancies, respectively. SNP array results of the couple appeared to be normal. The mother of the fetuses had a 46,XX,inv(1)(p31.1p32.1) karyotype., Conclusion: The paracentric inversion in chromosome 1 in the gravida probably underlies the recurrent 1p31.1 copy number variations in the fetuses. SNP-array combined with G banding chromosomal analysis are suitable for prenatal diagnosis for recurrent microdeletion and microduplication in the same chromosomal region, and can provide detailed information for genetic counseling.

Total RNA was extracted from placenta umbilical tissue and the canstatin cDNA was amplified from total RNA by net-RT-PCR technique. The amplified cDNA was cloned into pSP72 and sequenced. The canstatin cDNA was cut down from pSP72C with BamH I / Nde I and ligated into the vector pET-3c. The resultant plasmid pETC was then transformed into E. coli BL21 (DE3). The canstatin gene was efficiently expressed after IPTG induction as a 25 kD band on SDS-PAGE. The expressed product constituted approximately 27.9% of the total bacterial proteins estimated by densitometry and existed mainly as inclusion body. The inclusion bodies were washed, lysed, refolded and purified on the Sephadex G-75 gel filtration column to a purity of 91.4%. CAM assay showed that 10 microg purified canstatin is enough to inhibit the angiogenesis of chichen embryo microcapillary vessel.