Research progress on the exposure pathway and toxic effect of microplastics / 中国职业医学

Global plastics production has been increasing year by year. Due to the large quantity of plastics and the difficulty of their degradation, plastics are continuously accumulated in the environment. Therefore, plastic waste has become one of the most serious threats to the global environment. Microplastics can be absorbed into organisms through the mouth, respiratory tract and skin, causing organ(intestine, liver) toxicity, reproductive and developmental toxicity, and neurotoxicity. Moreover, microplastics can also take up other pollutants distributed in the surrounding environment, such as heavy metals and organic pollutants, jointly exerting combined toxic effects. The extracts of microplastics, including microplastics unstable polymers and additives, also have toxic effects. The molecular mechanisms involved in the toxic effects induced by microplastics include oxidative stress, inflammation, disturbance of intestinal flora, disturbance of gene expression, and others.

Identification of Dendrobium huoshanense, Dendrobium officinale and Dendrobium devonianum by multiplex allele-specific polymerase chain reaction / 药学学报

This study was designed to establish a multiplex allele-specific polymerase chain reaction method for simultaneous identification of Dendrobium huoshanense, D. officinale and D. devonianum, which may resolve identification problems of caulis dendrobii. Internal transcribed spacer sequences and trnL-trnF sequences of the Dendrobium species were aligned by BioEdit software, then specific SNPs of the three species were analyzed for designing allele-specific primers and the multiplex allele-specific PCR reaction system was established. The different origin of Dendrobium huoshanense, D. officinale and D. devonianum was amplified and identified by the sizes of respective band. The results showed that 584 bp, 397 bp and 211 bp bands could be amplified by D. devonianum, Dendrobium officinale and Dendrobium huoshanense respectively, when the annealing temperature was 61 ℃ and the number of cycles was 35. The limit of detection (LOD) of D. devonianum and D. huoshanense were both 1.2 ng, while D. officinale was low than 0.24 ng. The detection limit of adulterates in D. devonianum, D. devonianum and D. huoshanense mixture sample was 1%, 1% and 5% respectively. This result suggests that the method of multiplex allele-specific PCR is useful to identify D. huoshanense, D. officinale and D. devonianum is accurate and specific.

Conventional and molecular cytogenetic analyses of a derivative X chromosome in amniocentesis / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze the aberrant der(X) chromosome using conventional and molecular cytogenetic approaches in a fetus of second trimester and to discuss its clinical effect.</p><p><b>METHODS</b>Conventional cytogenetic procedures (GTG and CBG banding) were performed on cultured amniotic fluid cells. Three-color fluorescence in situ hybridization (FISH) consisting of X chromosome enumeration probes(CEPX), CEPY and Tel Xp/Yp was further performed to study the aberrant der(X) chromosome.</p><p><b>RESULTS</b>Der(X) was a rare X/Y translocation. The final karyotypes of the fetus was designated as: 46,X,der(X)t(X;Y)(p22.3;q11.2). ish der(X)t(X;Y)(p22.3;q11.2)(X/Ypter-, DXZ1+, DYZ1+)mat.</p><p><b>CONCLUSION</b>The combination of FISH and conventional cytogenetic techniques is a powerful tool to determine derivative chromosome and to offer an accurate genetic counseling. Identification of Xp; Yq rearrangement can help estimate the risk of fetus abnormalities and give a more precise prognosis.</p>

Sperm chromosome analysis and preimplantation genetic diagnos is in an infertile male with mosaic trisomy 18 / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze the numerical aberration rate of X, Y and chromosome 18 in sperms from an oligozoospermic male with mosaic trisomy 18 and to perform preimplantation genetic diagnosis (PGD) for the couple.</p><p><b>METHODS</b>G-banding and fluorescence in situ hybridization (FISH) were performed on metaphase chromosome. Sperm was analyzed in three-color FISH with a probe mixture containing CEP18, CEPY and Tel Xq/Yq. A healthy man with normal semen parameters was used as control.</p><p><b>RESULTS</b>Significant difference in the rates of disomy for chromosome 18 (0.63% vs. 0.16%) and the gonosomes (0.945% vs. 0.35%) and diploidy (0.87% vs. 0.31%) was found in the spermatozoa between the patient and the control. After four embryos were biopsied in one PGD cycle, two embryos with XY1818 and XX1818 were selected for implanting and clinical pregnancy was ongoing.</p><p><b>CONCLUSION</b>Sperm-FISH allows further understanding of aneuploidy rate and accurate genetic counseling. FISHPGD was effective for patient with mosaic trisomy 18.</p>

Sperm-fluorescence in situ hybridization analysis in patients with pericentric inversions of Y chromosome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze the sex chromosome meiotic segregation in inv(Y) patients by fluorescence in situ hybridization (FISH).</p><p><b>METHODS</b>Conventional cytogenetic procedures (GTG and CBG banding) and FISH were performed on metaphase chromosome. Three-color FISH was performed on sperm samples using a probe mixture containing CEPX, Tel Xp/Yp and Tel Xq/Yq to investigate the sex chromosome segregation of five inv(Y) (p11.1q11.2) carriers. A healthy man with normal semen parameters was used as control.</p><p><b>RESULTS</b>There was no statistical difference in the abnormal sex chromosome number and recombination frequencies in each spermatozoon from the patient in comparison with that in the control.</p><p><b>CONCLUSION</b>There was no apparent sex chromosome abnormality in the sperm of the inv(Y) (p11.1q11.2) carriers. Sperm-FISH allows further understanding of the sex chromosome segregation pattern and an accurate genetic counseling.</p>

Genetic analysis of a complex chromosome rearrangement involving two chromosomes and four breakpoints in an azoospermic man / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To perform genetic analysis of a complex chromosome rearrangement (CCR) 46,XY, t(3;11)(q27; q13), ins(11;3)(q13;p26p13) in an azoospermic man.</p><p><b>METHODS</b>Peripheral blood lymphocytes we re obtained for karyotyping, and metaphases were studied by multicolor fluorescence in situ hybridization procedure, Y chromosomal microdeletions in the azoospermia factor (AZF) region were analyzed with multiplex polymerase chain reaction.</p><p><b>RESULTS</b>The case was a complex chromosomal translocation between chromosomes 3 and 11 with four breakpoints, and accompanied with a band of chromosome 3 inserting into chromosome 11. No Y-chromosome microdeletions were identified at 6 STS sequences of the AZF loci.</p><p><b>CONCLUSION</b>CCR can have a significant impact on male fertility. Molecular cytogenetic techniques may contribute to improving and personalizing reproductive counseling.</p>

Purification technology of Rhizoma et Radix Notopterygii and Radix Angelicae Pubescentis in Fufang Xuelian dropping pills by macroporous resin / 中国中药杂志

<p><b>OBJECTIVE</b>To study the purification technology of Rhizoma et Radix Notopterygii and Radix Angelicae Pubescentis in Fufang Xuelian dropping pills by macroporous resin.</p><p><b>METHOD</b>Taking osthole, isomperatorin as index ingredients, the type of resin sampling amount and elution solvent were decided, and the influence of sample concentration pH of sample and ratio of diameter to height of column to adsorption were studied.</p><p><b>RESULT</b>HPD400A was chosen to purify, the suitable sampling ratio of resin volume to raw material was 1:2; pH 3.5 (crude drug) and ratio of diameter to height was 1:7; 95% ethanol of the elution solvent was satisfactory eluant for desorption.</p><p><b>CONCLUSION</b>HPD400A macroporous resin can be used to purify Rhizoma et Radix Notopterygii and Radix Angelicae Pubescentis.</p>