Study on pathogenic genes of dwarfism disease by next-generation sequencing

BACKGROUNDThere are many factors that lead to dwarfism, and the mechanism has not yet been elucidated. Next-generation sequencing may identify candidate-related gene mutations, which may clarify the molecular cause.AIMTo analyze genetic variation by using a constructed panel related to dwarfism by utilizing next-generation sequencing platform sequencing analysis to screen candidate-related gene mutations.METHODSPhysical and laboratory characteristics, including clinical examination, growth hormone drug challenge test, serum insulin-like growth factor-1 (IGF-1), IGF binding protein 3, other related tests, imaging examination, and chromosome karyotyping, were analyzed. Next-generation sequencing was performed to analyze pathogenicity variability.RESULTSIn the 39 dwarfism patients, 10 had pathogenicity variability. Gene variation was found in the OBSL1, SLC26A2, PTPN11, COL27AI, HDAC6, CUL7, FGFR3, DYNC2H1, GH1, and ATP7B genes. Of the 10 patients with pathogenicity variability, the related physical characteristics included double breast development and growth hormone deficiency, enuresis and indirect inguinal hernia on the left, two finger distance of 70.2 cm, head circumference of 49.2 cm, ischium/lower body length of 1.8 cm, weak limb muscles, and partial growth hormone deficiency. After 6 mo of growth hormone therapy, the concentrations of IGF-1 and IGF binding protein 3 increased from 215.2 ± 170.3 to 285.0 ± 166.0 and 3.9 ± 1.4 to 4.2 ± 1.1, respectively.CONCLUSIONOBSL1, SLC26A2, PTPN11, COL27AI, HDAC6, CUL7, FGFR3, DYNC2H1, GH1, and ATP7B genes may be related to the incidence of dwarfism, and more research needs to be performed to elucidate the mechanism.     

Elucidation of the functional role of flagella in virulence and ecological traits of Pseudomonas cichorii using flagella absence (ΔfliJ) and deficiency (ΔfliI) mutants

Understanding the infection mechanisms of pathogens will lead to better management of the associated diseases. The flagella of these pathogens play significant roles not only in bacterial motility, but also in virulence. In the present study, two genes involved in flagella construction, fliJ and fliI of Pseudomonas cichorii, were analyzed. The results revealed that these genes are vital for flagella formation and play significant roles not only in motility, but also in virulence. When we inoculated host plants with fliI- and fliJ-defective mutants (ΔfliJ and ΔfliI) through the dipping method, the degree of disease severity caused by both mutants was significantly reduced compared to those of the wild-type. However, the virulence of ΔfliI was stronger than that of ΔfliJ. Electron microscope observation, and swarming and leaf attachment assays indicated a reduced number of flagella in ΔfliI, but not complete absence, because of the presence of another copy of fliI. Furthermore, a vacuum infiltration assay revealed that flagella are indispensable in the pre- and post-penetration stages for complete virulence. Overall, we created semi-defective (ΔfliI) and completely defective (ΔfliJ) mutants and elucidated the fact that flagella play significant roles in virulence of the pathogen at different stages of the infection process.     

Lactobacillus fermentum,a pathogen in documented cholecystitis

INTRODUCTIONLactobacillus species are probiotics proven to exhibit various preventative as well as therapeutic properties. While lactobacillus species have been implicated in the formation of dental caries, endocarditis and bacteremia, their role as pathogens in cholecystitis has not been reported. We present a rare case of Lactobacillus fermentum working as a pathogen in cholecystitis.PRESENTATION OF CASEAn 81-year old male was admitted with right upper quadrant abdominal pain. His signs, symptoms, laboratory values and imaging were consistent with a diagnosis of cholecystitis with ascending cholangitis. In view of his co-morbidity and severe sepsis, the patient was treated non-operatively with antibiotics and cholecystostomy. L. fermentum, which was vancomycin resistant, was identified from the cholecystostomy aspirate and from anaerobic blood culture. The patient went into septic shock, developed multi-organ dysfunction syndrome and eventually died.DISCUSSIONCommensal bacteria such as L. fermentum are known to modulate immunity, reduce the pathogenicity of gastrointestinal organisms and play a therapeutic role in various disease processes. We isolated L. fermentum as a pathogen in a documented case of cholecystitis with ascending cholangitis.CONCLUSIONWhile the routine use lactobacillus species as a probiotic is supported in the literature, understanding its potential role as a pathogen may allow more judicious use of these bacteria and encourage research to elucidate the pathogenicity of lactobacillus species.     

牙龈卟啉单胞菌rag位点基因分型与细菌毒力的关系研究

目的：探讨牙龈卟啉单胞菌rag位点基因分型与细菌毒性的关系。方法将不同rag基因位点的牙龈卟啉单胞菌W83(rag-1型)、A011/9(rag-2型)、QM220(rag-3型)和ATCC33277(rag-4型)菌株分别刺激中性多形核白细胞,未受刺激的中性多形核白细胞作为对照。采用RT-PCR检测FcγⅢb受体基因,流式细胞术检测中性多形核白细胞凋亡情况,试剂盒检测毒力因子。结果 W83组 FcγⅢb基因相对表达量显著高于其他组( P <0．05),其次为QM220组,显著高于A011/9和ATCC33277组(P<0.05)。流式细胞术检测发现,ATCC33277组细胞凋亡率显著高于其他各组(P<0.05),A011/9组凋亡率显著高于W83组(P<0.05)。各基因分型组LPS、LBP、mCD14、MMP-8 MMP-9、IL-8以及IL-1β均高于对照组(P<0.05)。W83组上述指标显著高于其他各基因型组(P<0.05),QM220组次之,与 A011/9、ATCC33277组比较差异有统计学意义(P <0.05)。 A011/9组在 LPS、LBP、mCD14方面高于ATCC33277组(P<0.05),而MMP-8、MMP-9两者差异无统计学意义(P>0.05)。结论牙龈卟啉单胞菌菌株中rag位点基因分型的细菌毒性rag-1型最强,rag-3型次之,较弱的为rag-2型和rag-4型。     

B型流感病毒冷适应株B/Yamagata/16/88反向遗传操作平台的搭建及BALB/c小鼠感染模型的建立

【摘要】 目的 本研究利用基因工程技术全基因合成B型流感病毒冷适应株B/Yamagata/16/88的8个基因节段,并利用反向遗传技术从体外拯救B型流感病毒冷适应株B/Yamagata/16/88,同时建立BALB/c小鼠感染模型,为下一步研究B型流感病毒致病机制、传播机制以及开发新型疫苗奠定基础。方法 通过基因合成和反向遗传技术体外拯救B型流感病毒冷适应株B/Yamagata/16/88。全基因组测序验证拯救病毒基因组序列与Genbank序列的一致性。将拯救病毒以105EID50的攻毒剂量人工感染BALB/c小鼠,通过体重变化、生存率、肺脏病毒复制等方面进行致病性分析,建立小鼠感染模型。结果 成功从体外拯救出B型流感病毒冷适应株B/Yamagata/16/88,命名为B-S9。全基因组测序结果表明,B-S9基因组序列与Genbank公布序列一致。B-S9能够人工感染BALB/c小鼠,但不致死,对BALB/c小鼠呈现低致病性; 攻毒后第3天,B-S9感染小鼠体重出现下降,攻毒后第8天,小鼠体重开始回升;攻毒后第3天和第6天,B-S9感染小鼠的肺脏内均能检测到病毒复制,且攻毒后第3天的小鼠肺脏病毒滴度比攻毒后第6天的小鼠肺脏滴度高132倍。结论 成功搭建B型流感病毒冷适应株B/Yamagata/16/88反向遗传操作平台,并建立BALB/c小鼠感染模型。目前国内外对B型流感病毒的研究还较少,该反向遗传操作平台的建立为B型流感病毒致病机制和传播机制的研究奠定了基础,同时也为包括B型流感病毒减毒活疫苗在内的新型疫苗的研制开辟了新途径。     

人体蠕形螨致病性与致病因素的探讨

对新疆人体蠕形螨进行了流行病学调查，并对其致病性及致病因素进行了观察。发现人体蠕形螨感染率虽然高达６９．６０％，但有临床症状的并不多，人体蠕形螨不但与酒渣鼻、痤疮等皮肤病有关，而且与急性结膜炎、脸缘炎、，沙眼等眼外疾病有关，大多数受染者在一定的外部环境影响。     

肠道病毒衣壳蛋白致病性研究进展

肠道病毒是人类感染率很高的一种病毒,其衣壳蛋白在病毒的致病性方面起着重要的作用.近年来,大量的研究工作致力于肠道病毒农壳蛋白的致病性研究.此文就衣壳蛋白的基因组结构、基因分型、与病毒受体的相互作用和疫苗研制等方面作了综述.     

利用 DNA 序列对错义突变的致病性进行预测

错义突变的致病性预测在基因组学和临床研究中有重要作用,其中基于计算方法的预测工具已经取得较大进展。现有的工具大多根据功能影响、保守性来对错义突变的致病性进行预测,从 DNA 序列出发进行错义突变致病性预测的工具较少。随着自然语言处理技术在多个生物序列领域的迁移学习和应用,将 DNA 序列作为一种生物语言进行处理并进行基因突变的致病性预测越来越值得探索。该文提出了一个基于预训练的自然语言模型 DNABert 和 DNA 突变序列对错义突变致病性进行预测的深度学习模型MissenseBert,并且在多个数据集上对MissenseBert进行了训练和测试,测试结果说明MissenseBert取得了较好的预测效果,证明了利用 DNA 序列预测错义突变的致病性具有可行性。