Evolutionary Classification of Homeodomains

Purpose and Methods: We performed multiple comparisons between available amino acid (aa) sequences of homeodomain(HOM)-containing proteins from a wide spectrum of animals to create an evolutionary classification of the proteins. Results: Based on results of statistical and special computational analyses of over 500 homeodomain aa sequences (HOMs) a novel system of concepts describing complex structural correlations between homologous proteins is proposed. This system includes such notions as differentiated isofunctionality of aa, chemotype, stereotype, local functional motifs, gradual conservativeness of aa positions, and group-specific domain patterns, as well as major categories of the evolutionary classification of HOMs (Division, Type, Branch, Class, Family, Series, Variety, Sort). Using this approach, a complete structural systematics of HOMs belonging to proteomes of eukaryotic animals is proposed. Conclusions: The proposed structural classification of HOMs is in full agreement with the bulk of experimental data revealing complex functional similarities and differences among HOMs in terms of their expression patterns in developing embryos. It turn, this classification can provide answers regarding homology among homeodomains when experimental data are conflicting.     

脂蛋白脂肪酶基因突变的研究

目的：筛查国人脂蛋白脂肪酶(LPL)基因的突变，并探讨其与高甘油三酯血症的关系。方法：对高甘油三酯血症组(48例)和正常甘油三酯对照组(121例)的各扩增片段进行分析，电泳图谱异常者进行PCR产物测序。对于频率较高的多态性位点，引入限制性核酸内切酶位点利用PCR-RFLP进行鉴定。结果：在高甘油三酯血症人群中，检出2例内含子3受位剪接点上游6bp的C→T转换的突变杂合子，1例外显子5Pm^207→Leu突变杂合子，在全部样品中检出1例Ser^447→stop突变纯合子，50例Ser^447→stop杂合子。结论：天津地区人群中存在着LPL基因突变，除Ser^447→stop外，内含子3和外显子5的突变多与高甘油三酯血症相关，可能是高甘油三酯血症的遗传易感因子。     

内源性一氧化碳对肺动脉平滑肌细胞增殖基因表达谱的影响

目的 运用芯片技术研究内源性一氧化碳（CO）刺激下血管平滑肌细胞内增殖相关基凼表达谮的变化。方法 取SD大鼠肺动脉平滑肌细胞进行离体培养,用血小板源性生长因子（PDGF,20ng／m1）和Hemin（20μmol／L）进行刺激后,用Affymetrix表达基因谱芯片检测其基因表达谱变化。结果 Hemin刺激与PDGF刺激相比差异表达基因366条,与增殖相关的差异表达基因21条,上调11条,下调10条。其中原来在PDGF刺激下上调表达的一些基因（Map2k3、cyclinD1、PDGFA、mybL1、a．nape10、MMP14等）在经内源性CO刺激后其表达则显著下调。结论 内源性CO很可能是通过作用于MAPK途径来抑制PDGF的促增殖功能,同时伴有cyclinD1、cyclinG1、P21等的参与。     

A Unique Robust Dual-Promoter-Driven and Dual-Reporter-Expressing SARS-CoV-2 Replicon: Construction and Characterization

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2, SARS2) remains a great global health threat and demands identification of more effective and SARS2-targeted antiviral drugs, even with successful development of anti-SARS2 vaccines. Viral replicons have proven to be a rapid, safe, and readily scalable platform for high-throughput screening, identification, and evaluation of antiviral drugs against positive-stranded RNA viruses. In the study, we report a unique robust HIV long terminal repeat (LTR)/T7 dual-promoter-driven and dual-reporter firefly luciferase (fLuc) and green fluorescent protein (GFP)-expressing SARS2 replicon. The genomic organization of the replicon was designed with quite a few features that were to ensure the replication fidelity of the replicon, to maximize the expression of the full-length replicon, and to offer the monitoring flexibility of the replicon replication. We showed the success of the construction of the replicon and expression of reporter genes fLuc and GFP and SARS structural N from the replicon DNA or the RNA that was in vitro transcribed from the replicon DNA. We also showed detection of the negative-stranded genomic RNA (gRNA) and subgenomic RNA (sgRNA) intermediates, a hallmark of replication of positive-stranded RNA viruses from the replicon. Lastly, we showed that expression of the reporter genes, N gene, gRNA, and sgRNA from the replicon was sensitive to inhibition by Remdesivir. Taken together, our results support use of the replicon for identification of anti-SARS2 drugs and development of new anti-SARS strategies targeted at the step of virus replication.     

Café-au-lait macules and pediatric malignancy caused by biallelic mutations in the DNA mismatch repair (MMR) gene PMS2

A 14-year-old male presented with a T4 sigmoid adenocarcinoma, <10 colonic adenomas and multiple café-au-lait macules. Family history was not suggestive of a dominant hereditary form of colorectal cancer. Evaluation of the tumor revealed abnormal immunohistochemical staining of the PMS2 protein and high frequency microsatellite instability. Germline analysis identified biallelic PMS2 missense mutations. A new cancer syndrome caused by biallelic mutations in the mismatch repair genes, including PMS2, is now emerging and is characterized by café-au-lait macules, colonic polyps and a distinctive tumor spectrum.     

多重PCR法检测结核分枝杆菌耐药基因研究

目的:建立多重PCR法快速检测结核分枝杆菌耐药基因。方法:采用多重聚合酶链反应(PCR)同时扩增46株结核分枝杆菌临床分离株、48株北京标准菌株、40例耐药及40例非耐药的结核分枝杆菌临床分离菌株的inhA、katG、rpoB、IS1081等基因并采用测序的方法进行验证。结果:所有耐药样本基因(包括利福平、异烟肼耐药基因)及野生型菌株均被成功扩增。结论:应用多重PCR技术可同时快速检测结核分枝杆菌耐药基因。     

CD73在NPM1突变型急性髓系白血病患者中的表达及其临床意义

目的:探讨CD73在NPM1突变型及野生型急性髓系白血病(AML)患者中的表达及对其治疗疗效和预后的判断价值.方法:选取2015年6月-2019年6月本院收治的初治AML患者160例,同期选取本院非AML者的骨髓样本40例作为对照,分别比较健康者、NPM1突变型AML及NPM1野生型AML患者中CD73的表达,分析CD...     

Can Radiotherapy Empower the Host Immune System to Counterattack Neoplastic Cells? A Systematic Review on Tumor Microenvironment Radiomodulation

Despite the rising evidence in favor of immunotherapy (IT), the treatment of oncological patients affected by so-called “cold tumors” still represents an open issue. Cold tumors are characterized by an immunosuppressive (so-called cold) tumor microenvironment (TME), which favors host immune system suppression, cancer immune-escape, and a worse response to IT. However, the TME is not a static element, but dynamically mutates and can be changed. Radiotherapy (RT) can modulate a cold microenvironment, rendering it better at tumor killing by priming the quiescent host immune system, with a consequent increase in immunotherapy response. The combination of TME radiomodulation and IT could therefore be a strategy for those patients affected by cold tumors, with limited or no response to IT. Thus, this review aims to provide an easy, rapid, and practical overview of how RT could convert the cold TME and why cold tumor radiomodulation could represent an interesting strategy in combination with IT.     

Gut Microbiome Changes Occurring with Norovirus Infection and Recovery in Infants Enrolled in a Longitudinal Birth Cohort in Leon,Nicaragua

Noroviruses are associated with one fifth of diarrheal illnesses globally and are not yet preventable with vaccines. Little is known about the effects of norovirus infection on infant gut microbiome health, which has a demonstrated role in protecting hosts from pathogens and a possible role in oral vaccine performance. In this study, we characterized infant gut microbiome changes occurring with norovirus-associated acute gastroenteritis (AGE) and the extent of recovery. Metagenomic sequencing was performed on the stools of five infants participating in a longitudinal birth cohort study conducted in León, Nicaragua. Taxonomic and functional diversities of gut microbiomes were profiled at time points before, during, and after norovirus infection. Initially, the gut microbiomes resembled those of breastfeeding infants, rich in probiotic species. When disturbed by AGE, Gammaproteobacteria dominated, particularly Pseudomonas species. Alpha diversity increased but the genes involved in carbohydrate metabolism and glycan biosynthesis decreased. After the symptoms subsided, the gut microbiomes rebounded with their taxonomic and functional communities resembling those of the pre-infection microbiomes. In this study, during disruptive norovirus-associated AGE, the gut microbiome was temporarily altered, returning to a pre-infection composition a median of 58 days later. Our study provides new insights for developing probiotic treatments and furthering our understanding of the role that episodes of AGE have in shaping the infant gut microbiome, their long-term outcomes, and implications for oral vaccine effectiveness.