OBJECTIVE: To report on a case of mosaicism involving trisomy 21, maternal uniparental isodisomy, and normal diploid cells in uncultured amniocytes, and to explore the discrepancies between conventional cytogenetic and molecular cytogenetic techniques during prenatal diagnosis. METHODS: A 30-year-old pregnant woman who presented to Boai Hospital of Zhongshan on June 27, 2023 has undergone amniocentesis at 16 weeks of gestation. The amniotic fluid sample was subjected to quantitative fluorescent PCR (QF-PCR), G-banded karyotype analysis, and chromosomal microarray analysis (CMA). The discrepancies between the results of each method were analyzed. This study was approved by Medical Ethics Committee of Boai Hospital of Zhongshan (Ethics No.: KY-2024-001-01). RESULTS: Non-invasive prenatal testing (NIPT) at 12 weeks indicated a high risk of trisomy 21. QF-PCR of uncultured amniocytes revealed a pattern of trisomy 21. After one week of cell culture, G-banding analysis showed mos 47,XX,+21[1]/46,XX[72]. CMA revealed a homozygous state of chromosome 21 in cultured cells, while uncultured amniocytes showed mosaic trisomy 21 with an estimated proportion of 50%. These findings suggested a complex chromosomal mosaicism in the fetus, which may result from a trisomy rescue event during early embryogenesis, leading to coexistence of three cell lines including trisomy 21, maternal uniparental isodisomy, and normal diploid cells. CONCLUSION In prenatal diagnosis, discrepancies may arise between QF-PCR and conventional chromosomal karyotyping analysis, particularly in complex genetic phenomena such as trisomy rescue and uniparental disomy. For cases where NIPT indicated a high risk of trisomy 21 but G-banding karyotype analysis yielded a normal result, further molecular genetic testing using uncultured cells is recommended.
Humans ; Female ; Mosaicism ; Pregnancy ; Uniparental Disomy/diagnosis* ; Adult ; Down Syndrome/diagnosis* ; Prenatal Diagnosis/methods* ; Diploidy ; Karyotyping ; Amniocentesis

Pancreatic cancer (PC) is a malignant digestive tract tumor with poor prognosis. Most of patients with PC are insensitive to traditional strategies of chemotherapy, targeted therapy and immunotherapy. PC with microsatellite instability-high/deficient mismatch repair (MSI-H/dMMR) is rare in clinic, which has distinctive clinicopathological characteristics and better prognosis from conventional PC. Reasonable acquisition of pancreatic tumor biopsy and accurate assessment of MSI-H/dMMR status are helpful for accurate diagnosis of such patients. Individualized treatment strategy based on immunotherapy can significantly improve the prognosis of patients with MSI-H/dMMR PC. Based on relevant literatures of domestic and foreign, the authors discuss the current status and research hotspots of diagnosis and treatment for MSI-H/dMMR PC.

Objective To investigate the correlation between serum retinol-binding protein 4 (RBP4) level and stroke severity and short-term outcome in patients with acute ischemic stroke.Methods From January 2017 to December 2017,patients with acute ischemic stroke admitted to the Department of Neurobgy,the Third Affiliated Hospital of Anhui Medical University and who did not receive thrombolytic or endovascular treatment were enrolled retrospectively within 2 weeks of onset.The serum RBP4 levels were measured within 24 h of admission and the demographics and baseline clinical data of the patients were documented.On the day of admission,the National Institutes of Health Stroke Scale (NIHSS) was used to assess the degree of neurological deficit;≤8 was defined as mild stroke and ＞8 was defined as moderate to severe stroke.The modified Rankin scale was used to assess the short-term outcomes at the time of discharge or 14 days after onset;0 to 2 were defined as good outcomes,and ＞ 2 was defined as poor outcome.Results A total of 235 patients were enrolled,including 101 females (43％) and 134 males (57％);aged (66.8 ± 1.7) years (range 28-93 years).There were 200 mild strokes (85.1％) and 35 moderate to severe strokes (14.9％);171 (72.8％) had good outcomes and 64 (27.2％) had poor outcomes.Univariate analysis showed that the serum RBP4 level in the moderate to severe stroke group was significantly lower than that in the mild stroke group (29.28 ± 10.43 mg/L vs.36.88 ± 10.61 mg/L;t =3.920,P ＜ 0.001),and the RBP4 level in the poor outcome group was significantly lower than that in the good outcome group (32.03 ± 11.33 mg/L vs.37.14± 10.44 mg/L;t=3.264,P=0.001).Multivariate logistic regression analysis showed that the high serum RBP4 level was independently correlated with the milder stroke severity (odds ratio 0.917,95％ confidence interval 0.874-0.962;P ＜0.001) and short-term poor outcome (odds ratio 0.955,95％ confidence interval 0.927-0.983;P =0.002).Conclusion In patients with high serum RBP4 levels,acute ischemic stroke is less severe and better in short-term outcomes.

Objective To investigate the risk factors and MRA manifests in the patients with cortical wa-tershed infarcts(CWSI)or internal watershed infarcts(IWSI).Methods We collected the patients with acute wa-tershed infarcts in our hospital from January 2013 to April 2016.According to the Bogousslavsky classification stan-dard,the patients were divided into two groups:CWSI and IWSI. The two groups were compared in terms of risk factors and MRA manifests. Results We included 36 CWSI and 11 IWSI patients in the study.There were signifi-cant differences in smoke,diabetes mellitus,fasting blood glucose levels and carotid atherosclerotic plaque be-tween the two groups,and so it was with the stenosis of ICA,MCA,ACA,PCA,VA and BA:The stenosis of ICA in the CWSI group was more serious than in the IWSI group,but the stenosis of MCA,ACA,PCA,VA and BA in the IWSI group was more serious than in the CWSI group. Conclusions The pathogenesis of CWSI may be related to the formation of carotid atherosclerotic plaques,carotid stenosis and arterial artery embolism,or plaque shedding and micro emboli removal.The pathogenesis of IWSI may be related to the decrease of the perfusion pres-sure at the end of the intracranial artery.The ratio of IWSI to diabetes mellitus is higher than that of CWSI,suggest-ing that the damage of diabetes to intracranial arteriole is earlier than that of intracranial and extracranial arteries.

BACKGROUNDAn amino acid polymorphism for Met to Val has been identified at PrP codon 129 from different human races. In this study,the characteristics of polymorphism of PRNP 129th amino acid in Han and Uighur Chinese have been investigated.

METHODSHuman DNAs were extracted from peripheral lymphocytes and PrP gene fragments were amplified with a specific PCR protocol. The distribution of 129th amino acid in PRNP was determined by a PCR-RFLP and the results were analyzed with software SAS for Windows 6.12.

RESULTSThe frequencies of the allele 129 Met and 129 Val were 97.0% and 3.0% in Han Chinese, whereas 91.4% and 8.6% in Uighur Chinese. The frequency of 129 M/M phenotypes in Han Chinese was significantly higher than that in Uighur Chinese (P=0.0490). Comparing the phenotype distributions of codon 129 of Han Chinese with that of Japanese and Caucasian, there was significant difference with Caucasian (P=0.0005),but there was no difference with Japanese (P=0.5040).

CONCLUSIONSThe polymorphism of 129th amino acid in PRNP of Han Chinese is similar to Japanese, but different from Uighur Chinese.

Asian Continental Ancestry Group ; genetics ; China ; Codon ; genetics ; European Continental Ancestry Group ; genetics ; Gene Frequency ; Genotype ; Humans ; Polymorphism, Genetic ; Prion Diseases ; genetics ; Prions ; genetics

BACKGROUNDTo establish a sandwich ELISA method for detection of reporter chloramphenicol acetyltransferase (CAT) gene.

METHODSThe full length sequence of CAT gene was amplified with PCR using plasmid pBLCAT6 as template, and inserted into the prokaryotic expression plasmid Pgex-2T. The purified fusion protein was emulsified with complete or incomplete Freund adjuvant and injected subcutaneously into rabbits. The antibody was labeled with biotin, and a sandwich ELISA technique with biotin streptavidin amplify system was established. Several CAT reporter plasmids containing different HPV 16 LCR sequences were generated and transfected transiently to monolayer cells in vitro. The cytoplasm proteins were extracted and the expressions of CAT were evaluated with the newly established ELISA assay.

RESULTSSDS-PAGE displayed that the molecular weight of the expressed fusion protein was about 54,000. The prepared antiserum was able to recognize the CAT protein expressed by mammalian cells or prokaryote cells. Under the control of different promoters and their regulate sequences,two to eight folds CAT expression increased were evaluated in transiently transfected mammalian cells by the newly established sandwich ELISA method.

CONCLUSIONSThe established method could sensitively reflect the activities of the upstream promoters, as well as the influence of exchanges of nucleotides within the regulate region on the promoter activities. Therefore, it proposes a convenient assay for the studies using CAT as the reporter gene.

Animals ; Antibodies ; analysis ; Cells, Cultured ; Chloramphenicol O-Acetyltransferase ; analysis ; genetics ; immunology ; Enzyme-Linked Immunosorbent Assay ; methods ; Genes, Reporter ; Male ; Papillomaviridae ; genetics ; Plasmids ; genetics ; Rabbits ; Recombinant Fusion Proteins ; analysis ; biosynthesis ; immunology