Sentinel lymph node biopsy in rats. Comparison between paraffin and frozen section analysis

PURPOSE:To simulate a lymph node metastasis in an animal model using activated carbon, assess their identification in frozen section analysis and compare with histopathological examination in paraffin.METHODS:Thirty two adult female rats were used. They received the carbon injection on its hind legs. Half of the rats was sacrificed on day one, and the other half after 21 days. Thus, 64 lymph nodes were dissected and split longitudinally. One half of the lymph node was sent immediately to frozen section analysis. The other half was fixed in 10% formaldehyde to be cut in paraffin. Slides were divided into quadrants and classified by the presence of carbon in these four quadrants_ They were also classified by the carbon staining intensity.RESULTS:Comparing the slides obtained in the first day and 21 days, there was a tendency of carbon to spread over time, but without statistical significance. The intensity did not alter over time.CONCLUSION:There was no concordance between the two methods of pathological analysis, however the actived carbon was seen in all lymph nodes.UNIFESPUNIFESP Pathology DepartmentUniversidade Federal de São Paulo (UNIFESP) Department of SurgeryUNIFESP, Pathology DepartmentUNIFESP, Department of SurgerySciEL

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection