Near-haploid karyotype in a squamous cell lung carcinoma

Cytogenetic analysis of a squamous cell lung carcinoma revealed a near-haploid karyotype with 27 chromosomes, in both primary cultures and an established cell line. The only chromosomes with two homologs present were chromosomes X, 5, 7, and 22. The two X chromosomes were early and late replicating, respectively. No structural rearrangements could be detected. In vitro, the clone evolved by duplication towards hyperdiploidy with 54 chromosomes. © 1993 Wiley-Liss, Inc.     

L’économie comportementale au service de la santé

The COVID-19 pandemic is bringing about far-reaching structural changes on both the economy and public health, and conventional methodologies have to be fine-tuned to assist public health decision making. In this context, behavioural economics, which is situated at the crossroads between economics and social psychology, is an undeniably innovative field. In contrast with conventional models, the economic models of behavioural economics incorporate psychological and social determinants to produce more accurate predictions of individual behaviour. In the last 20 years, the scientific community has been using this approach’s quantitative tool, experimental economics, in many areas of health, including prevention, promotion, human resources and social signage. Studies have come up with effective solutions that have improved best public health practices and provided sources of inspiration that should not be overlooked in the fight against COVID-19. They have allowed natural human behaviour to take a central role again, helped us to understand how the social and economic environment influences individuals, and enabled us to anticipate human reactions and so make faster adjustments to public policies.     

镍钛形状记忆合金细胞相容性和生物力学兼容性的改进

镍钛记忆合金（ＮｉＴｉ）生物材料器件的发展，迫切要求研究和提高其细胞相容性和生物力学性能。依据美国材料测试标准协会（ＡＳＴＭ）的标准，我们研究表明：ＮｉＴｉ的细胞毒性比纯钛、Ｔｉ６Ａ１４Ｖ和３１６Ｌ不锈钢大，在ＮｉＴｉ表面作聚合四氟乙烯高离子（ＰＰＴＦＥ）喷涂。可降低ＮｉＴｉ合金的细胞毒性，提高其抗腐蚀力。各种热处理方法可改善其疲劳性能，循环拉伸强度试验可测出其超弹性性能的衰减。     

A key role for EZH2 and associated genes in mouse and human adult T-cell acute leukemia

In this study, we show the high frequency of spontaneous γδ T-cell leukemia (T-ALL) occurrence in mice with biallelic deletion of enhancer of zeste homolog 2 (Ezh2). Tumor cells show little residual H3K27 trimethylation marks compared with controls. EZH2 is a component of the PRC2 Polycomb group protein complex, which is associated with DNA methyltransferases. Using next-generation sequencing, we identify alteration in gene expression levels of EZH2 and acquired mutations in PRC2-associated genes (DNMT3A and JARID2) in human adult T-ALL. Together, these studies document that deregulation of EZH2 and associated genes leads to the development of mouse, and likely human, T-ALL.     

Trisomy 8 and monosomy 7 detected in bone marrow using primed in situ labeling, fluorescence in situ hybridization, and conventional cytogenetic analyses. A study of 54 cases with hematological disorders

Trisomy 8 and monosomy 7 are the two most frequent aneuploidies found in hematological disorders such as myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). In this study, primed in situ labeling (PRINS), fluorescence in situ hybridization (FISH) and conventional cytogenetic approaches were used to investigate 54 cases of hematopoietic disorders. Of these cases, there were 22 cases of trisomy 8, 2 cases of tetrasomy 8, 14 cases of monosomy 7, and 16 cases with two copies of both chromosomes 7 and 8. PRINS was carried out in interphase nuclei of bone marrow samples using primers that can specifically detect alpha-satellite DNA sequences of chromosomes 7 and 8. In parallel, using the alpha-satellite probes for chromosomes 7 and 8, FISH was performed for all the cases. PRINS and FISH techniques showed similar specificity and sensitivity. In comparison to FISH, PRINS is more advantageous since it is a faster, easier, and more cost-effective technique. Additionally, for most of the cases, a higher proportion of aneuploidy was detected in metaphases using conventional cytogenetics, as compared to the one found in interphase nuclei identified with PRINS and FISH techniques. In other words, for these cases, the cells with trisomy 8 or monosomy 7, had a distinct proliferative advantage compared to the disomic cell population. Therefore, to better quantify the proportion of aneuploid cells in bone marrow, we recommend to investigate the frequency of aneuploidy in nuclei using PRINS, rather than studying only the dividing cells as detected by conventional cytogenetic techniques.