一株嗜酸乳杆菌的分离与鉴定

桂林市黄洛瑶寨地区人群在洗发过程中长期使用淘米水发酵液,该地区发质和头发根部头皮质量都要优于其他地区,淘米水发酵液中益生菌对头发和头皮的影响值得关注。为了研究该地区淘米水发酵液中益生菌,对淘米水发酵液进行菌株的分离与鉴定。从淘米水发酵液中分离得到3株嗜酸乳杆菌疑似菌株,通过菌株菌落形态、显微形态、革兰氏染色、46项生理生化指标和分子生物学方法进行鉴定,结果表明3号菌株菌落形态、显微形态、革兰氏染色符合嗜酸乳杆菌特征;46项生理生化指标与嗜酸乳杆菌接近,鉴定可信度达到90%;经过16S rDNA鉴定后,其与嗜酸乳杆菌的同源性高达99%。综合多项检测结果确定其为嗜酸乳杆菌,并且命名为CFC-001。     

嗜酸乳杆菌黏附鸡胚肠黏膜上皮细胞能力的研究

目的建立肠黏膜上皮细胞模型和测定嗜酸乳杆菌的黏附能力。方法将嗜酸乳杆菌用胃蛋白酶和HCl-H2O低pH以及反复冻融、灭活等方法处理后测定其黏附能力。结果成功地建立了鸡胚肠黏膜上皮细胞模型;经胃蛋白酶和HCl-H2O低pH以及灭活处理后,嗜酸乳杆菌的黏附能力和对照组差异有显著性。反复冻融后的嗜酸乳杆菌黏附能力与对照组差异无显著性。结论胃蛋白酶和HCl-H2O pH2.0会使嗜酸乳杆菌黏附肠黏膜上皮细胞能力下降,热灭活可使嗜酸乳杆菌的黏附能力提高,反复冻融对嗜酸乳杆菌的黏附能力无明显影响。     

平菇菌丝发酵液粗多糖对多种肠道益生菌的影响

目的探究平菇菌丝发酵液粗多糖对多种肠道益生菌生长的影响。方法采用发酵工程技术获得平菇菌丝发酵液并提取平菇菌丝分泌的粗多糖。将平菇菌丝发酵液粗多糖分别以浓度10.0%、5.0%、2.5%以及0%的空白对照对青春双歧杆菌、干酪乳杆菌、乳杆菌MZ900、嗜酸乳杆菌生长的影响进行观察。结果在含平菇菌丝粗多糖10.0%以下的菌液范围内随着平菇菌丝发酵液粗多糖含量的增加,4种肠道益生菌的生长成正相关增长。结论平菇菌丝发酵液粗多糖对4种肠道益生菌有增菌效果。研究结果为平菇菌丝发酵液粗多糖有保护人类肠道功能的作用提供理论依据,以及为后续研究提供建议。     

益生菌联合柳氮磺胺吡啶治疗溃疡性结肠炎的疗效观察

【摘 要】 目的 通过建立葡聚糖硫酸钠(DSS)诱导的急性期溃疡性结肠炎(UC)小鼠模型,观察嗜酸乳杆菌以及联合柳氮磺胺吡啶对小鼠溃疡性结肠炎(UC)的治疗作用,并检测Hsp70、Hsp27在肠黏膜的表达,探讨其可能的作用机制。方法　5% DSS 7 d建立急性UC动物模型。将60只BALB/c小鼠随机分为6组：正常对照组、模型组、阴性对照(生理盐水,NS)组、嗜酸乳杆菌组、柳氮磺胺吡啶组和嗜酸乳杆菌联合柳氮磺胺吡啶组,观察指标包括：疾病活动指数(DAI)、结肠黏膜肉眼改变及病理组织学积分;采用免疫组化SABC 法检测热休克蛋白(HSP70)和(HSP27)的表达量。结果 嗜酸乳杆菌可降低实验小鼠DAI积分和改善结肠组织损伤;与模型组、阴性对照组相比,嗜酸乳杆菌联合柳氮磺胺吡啶组的HSP70表达增加(P＜0.05),其中以嗜酸乳杆菌联合柳氮磺胺吡啶组效果最佳。结论 嗜酸乳杆菌和柳氮磺胺吡啶对小鼠溃疡性结肠炎都有治疗作用,且二者疗效相当;两药联合应用效果最佳。其机制可能与增加结肠黏膜HSP70的表达有关。     

茯苓菌丝发酵液粗多糖对肠道益生菌的影响

目的探究茯苓菌丝发酵液中提取的粗多糖对肠道益生菌的影响。方法运用发酵工程相关技术获得茯苓菌丝发酵液,提纯分离以获取茯苓菌丝中分泌的粗多糖。将提取出的茯苓粗多糖以10.0%、5.0%、2.5%和空白对照(0.0%)的浓度对4种肠道益生菌——嗜酸乳杆菌、干酪乳杆菌、乳杆菌MZ900、青春双歧杆菌的生长进行观察。结果在茯苓粗多糖含量10.0%以下的范围内,10.0%、5.0%、2.5%浓度下肠道益生菌数量均高于对照组,并且随着茯苓发酵液粗多糖浓度的含量增加,4种肠道益生菌数量呈正相关增长。结论茯苓菌丝发酵液粗多糖对以上4种肠道益生菌有增菌效果。实验结果为茯苓菌丝发酵液粗多糖有保护人类肠道的作用提供理论依据,并为后续的生化研究与动物实验提供理论基础。     

细菌对肉鸡肠粘液的粘附作用

研究两歧双歧杆菌、嗜酸乳杆菌、禽大肠杆菌O78、大肠杆菌 ATCC 25922、鸡白痢沙门氏菌和鼠伤寒沙门氏菌与肉鸡不同部位肠粘液糖蛋白的粘附性能,探讨两歧双歧杆菌和嗜酸乳杆菌对所试病原菌的抗粘附作用。结果表明：在不同的肠道部位,两歧双歧杆菌、嗜酸乳杆菌、鸡白痢沙门氏菌和鼠伤寒沙门氏菌与肠粘液糖蛋白均有不同的粘附作用,而禽大肠杆菌O78、大肠杆菌 ATCC 25922在各肠段粘液上的粘附性能则相近;在相同的肠道部位,所试益生菌的粘附能力大于病原菌;两歧双歧杆菌和嗜酸乳杆菌对所试病原菌的粘附有不同的阻断作用,同时二者有时还存在互补抗粘附作用。     

双歧杆菌四联活菌片中嗜酸乳杆菌的分离及生长动力学研究

目的以双歧杆菌四联活菌片为实验材料,利用酸化的MRS培养基筛选分离得到嗜酸乳杆菌,对其进行进一步的生长动力学研究,确定嗜酸乳杆菌的生长数学模型。方法通过浓度梯度稀释法利用改良MRS培养基对双歧杆菌四联活菌片中的嗜酸乳杆菌进行分离,利用分光光度仪和平板菌落计数两种不同的方法测定嗜酸乳杆菌在发酵过程中不同发酵时间的细胞浓度的动态变化,经软件处理后拟合出嗜酸乳杆菌细胞生长的Logistic数学模型。结果Logistic方程能很好地拟合嗜酸乳杆菌细胞生长的动态变化,并得到嗜酸乳杆菌在本实验条件下的数学模型,为进一步研究、利用嗜酸乳杆菌生长能力、产酸能力和产香能力等具有重要的理论指导意义。     

乳杆菌对急性溃疡性结肠炎模型小鼠的疗效观察

目的观察植物乳杆菌YXCC-1和嗜酸乳杆菌YXCC-2对小鼠急性溃疡性结肠炎(UC)的疗效。方法对这两株菌进行体外模拟胃肠环境抗性研究,并进行动物实验。采用DSS诱导的小鼠急性UC模型,将60只小鼠随机分为4组,分别为空白对照组、DSS模型组、YXCC-1组和YXCC-2组,每组15只,观察小鼠治疗前后一般情况,计算小鼠组织学损伤评分以及观察组织学病理改变。结果菌株YXCC-1、YXCC-2有一定的耐酸、耐胆盐能力,在人工肠液环境下能较好存活;灌胃菌株发酵液可显著降低UC小鼠DAI水平,明显改善结肠组织损伤。结论植物乳杆菌YXCC-1、嗜酸乳杆菌YXCC-2发酵液对小鼠溃疡性结肠炎有治疗作用,且两者疗效相当。     

嗜酸乳杆菌与嗜热链球菌共发酵互生机理的研究

目的:对嗜酸乳杆菌和嗜热链球菌共发酵时两者的互生作用机理进行研究。方法:以质量浓度100gL脱脂乳为培养基,将嗜酸乳杆菌主要代谢产物—氨基酸,如赖氨酸、精氨酸、缬氨酸分别以0.0083mgml、0.0036mgml、0.0053mgml的量加入含嗜热链球菌脱脂乳培养基中,40℃培养,测定凝乳时间;将嗜热链球菌的代谢产物-乳酸、甲酸分别为0.1332mgml和0.075mgml的量加入含嗜酸乳杆菌脱脂乳培养基中,37℃培养,测定其发酵乳的凝乳时间。结果:嗜热链球菌发酵乳凝乳时间由12h缩短到4h,pH为4.52～4.62,吉尔涅尔度为54.23～64.74°T;嗜酸乳杆菌发酵乳的凝乳时间由16h缩短为5h,pH为4.61～4.65;且嗜酸乳杆菌在CO2环境中发酵时,发酵时间明显缩短。结论:嗜酸乳杆菌和嗜热链球菌共发酵时具有互生关系。     

复方嗜酸乳杆菌片联合美沙拉嗪对 溃疡性结肠炎患者肠黏膜的修复作用

目的探讨复方嗜酸乳杆菌片联合美沙拉嗪缓释颗粒对溃疡性结肠炎(UC)患者肠黏膜的修复作用。方法选取活动期UC患者74例,随机分为观察组和对照组各37例。两组患者均给予相同的饮食指导及营养支持治疗。对照组患者给予美沙拉嗪缓释颗粒1.0g/次,4次/d,口服。观察组在对照组基础上加用复方嗜酸乳杆菌片1.0g/次,3次d/。两组患者均连用12周。观察并记录两组患者治疗前和治疗12周后血清D-乳酸和PCT水平及肠镜下肠黏膜评分的变化,并比较其临床效果。结果治疗12周后,两组患者血清D-乳酸和PCT水平及及肠镜下肠黏膜评分均较治疗前有不同程度下降(P0.05),且观察组下降幅度较对照组更大(P0.05);同时观察组临床总有效率高于对照组(94.59%vs78.38%;χ~2=4.16,P0.05)。结论复方嗜酸乳杆菌片联合美沙拉嗪缓释颗粒对UC的治疗效果较肯定,可明显减轻患者肠黏膜病变程度,保护肠黏膜屏障,加快其修复。     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.