PBS, Phosphate buffered saline

PBS,磷酸盐缓冲盐水
  • 文章类型: Journal Article
    长时间输注高剂量的犬尿烯酸(KYNA)可降低大鼠脊髓中的髓磷脂含量,同时保留轴突完整性,并且不会引起炎症反应。我们假设硬膜下输注高浓度的KYNA可以诱导鸡视神经(ON)的髓磷脂损失。然而,现有的将代理递送到ON的方法效率低下,非局部暴露,仅提供急性暴露。因此,我们开发了一种将KYNA持续递送至鸡ON的手术方法。简而言之,新颖的外科技术,这不包括眼外肌的切除,涉及切开皮肤和下面的筋膜鞘以进入肌肉锥内的视神经,在视神经硬膜植入导管,另一端在皮肤下退出轨道。导管在外侧can附近的皮肤下延伸,从耳朵到脖子后面,其中进行第二切口以植入渗透泵并将导管附接到渗透泵。印度墨水用于确认对视神经和交叉的长期持续给药。该手术模型用于研究KYNA对ON中髓磷脂损失的影响。将7天大的鸡的ON用50mMKYNA或磷酸盐缓冲盐水(PBS)输注7天。对KYNA输注的对侧ONg比率和蛋白质水平的分析表明髓鞘减少。这些发现证明了我们的手术方法用于将KYNA持续递送到ON的实用性,并暗示了KYNA在调节CNS髓鞘形成中的作用。
    Prolonged infusion of a high dose of kynurenic acid (KYNA) reduces the myelin content in the rat spinal cord with preservation of the axonal integrity and without inducing an inflammatory response. We hypothesized that subdural infusion of a high concentration of KYNA can induce myelin loss in the optic nerves (ONs) of chickens. However, existing methods to deliver agents to the ON are inefficient, unlocalized and provide only acute exposure. Thus, we developed a surgical approach for sustained delivery of KYNA to the chicken ON. In brief, the novel surgical technique, which does not include excision of the extraocular muscles, involves incision of the skin and underlying fascial sheath to access the optic nerve within the muscle cone, implantation of a catheter in the dura of the optic nerve, the other end of which exits the orbit under the skin. The catheter runs under the skin near the lateral canthus, over the ears to the back of the neck, where a second incision is made to both implant the osmotic pump and to attach the catheter to the osmotic pump. India ink was used to confirm prolonged sustained administration to the optic nerves and across the chiasm. This surgical model was used to investigate KYNA\'s effect(s) on myelin loss in the ON. ONs of 7-day old chickens were infused with 50 mM KYNA or phosphate buffered saline (PBS) for seven days. Analysis of KYNA-infused contralateral ON g-ratios and protein levels indicated a reduction in myelin. These findings demonstrate the utility of our surgical approach for sustained delivery of KYNA into the ON and suggest a role for KYNA in modulating CNS myelination.
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  • 文章类型: Journal Article
    COVID-19大流行强调了公众对室内空气传播疾病的认识,并强调需要可靠的空气消毒技术。这种意识的提高将与不断出现的SARS-CoV变体一起在大流行后时代继续存在,需要有效和明确的协议,方法,和空气消毒装置。基于紫外线(UV)的空气消毒在灭活病毒生物气溶胶方面表现出了有希望的结果。然而,报告的所需UVC剂量的数据多样性阻碍了确定最佳UVC实践,并导致公众和监管机构之间的混淆.本文回顾了有关影响UVC空气消毒系统功效的关键参数的可用信息,因此,所需剂量包括系统的组件以及操作和环境因素。在文献中有一个共识,即湿度和空气温度的相互关系对UVC敏感性有显著影响。这转化为在不同条件下改变室内环境中商业化设备的UVC功效。据报道,采样和雾化技术对结果解释有重大影响,建议同时使用几种采样方法来生成可比和结论性的数据。我们还考虑了UVC的安全问题和潜在的安全替代品,远紫外线。最后,代表了每个关键参数的差距和该领域未来的研究需求。本文是巩固文献的第一步,以开发UVC空气消毒设备的标准验证协议,该协议被确定为研究需求之一。
    The COVID-19 pandemic highlighted public awareness of airborne disease transmission in indoor settings and emphasized the need for reliable air disinfection technologies. This increased awareness will carry in the post-pandemic era along with the ever-emerging SARS-CoV variants, necessitating effective and well-defined protocols, methods, and devices for air disinfection. Ultraviolet (UV)-based air disinfection demonstrated promising results in inactivating viral bioaerosols. However, the reported data diversity on the required UVC doses has hindered determining the best UVC practices and led to confusion among the public and regulators. This article reviews available information on critical parameters influencing the efficacy of a UVC air disinfection system and, consequently, the required dose including the system\'s components as well as operational and environmental factors. There is a consensus in the literature that the interrelation of humidity and air temperature has a significant impact on the UVC susceptibility, which translate to changing the UVC efficacy of commercialized devices in indoor settings under varying conditions. Sampling and aerosolization techniques reported to have major influence on the result interpretation and it is recommended to use several sampling methods simultaneously to generate comparable and conclusive data. We also considered the safety concerns and the potential safe alternative of UVC, far-UVC. Finally, the gaps in each critical parameter and the future research needs of the field are represented. This paper is the first step to consolidating literature towards developing a standard validation protocol for UVC air disinfection devices which is determined as the one of the research needs.
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  • 文章类型: Journal Article
    呼吸道合胞病毒(RSV)是全球儿童病毒性细支气管炎的最常见原因,目前还没有针对RSV疾病的疫苗。这项研究调查了在体外和体内存在RSV感染的情况下,立方体和球形氧化铈纳米颗粒(CNP)调节活性氧(ROS)和氮(RNS)物种和免疫细胞表型的潜力。通过水热和超声方法合成了立方体和球形CNP,分别。物理化学表征证实了球形和立方体CNP的形状以及各种参数对其粒度分布和ζ电位的影响。体外结果表明,球形和立方体CNP差异调节J774巨噬细胞中的ROS和RNS水平。具体来说,立方体CNP显着降低RSV诱导的ROS水平而不影响RNS水平,而球体CNP增加RSV诱导的RNS水平,对ROS水平的影响最小。CubeCNP通过增加CD80和CD86的巨噬细胞表面表达并伴随TNFα和IL-12p70的增加,同时降低M2CD206表达,在体外驱动了RSV感染的巨噬细胞的M1表型。在BALB/c小鼠中,鼻内施用球体和立方体-CNP是良好耐受的,没有观察到毒性。值得注意的是,立方CNP优先积累在鼠肺泡巨噬细胞中并诱导其激活,避免其他炎症细胞如嗜中性粒细胞的摄取和活化增强,与RSV介导的炎症相关。总之,我们报道了球形和立方体CNP在RSV感染期间调节巨噬细胞极化和先天细胞反应。
    Respiratory syncytial virus (RSV) is the most common cause of viral bronchiolitis among children worldwide, yet there is no vaccine for RSV disease. This study investigates the potential of cube and sphere-shaped cerium oxide nanoparticles (CNP) to modulate reactive oxygen (ROS) and nitrogen (RNS) species and immune cell phenotypes in the presence of RSV infection in vitro and in vivo. Cube and sphere-shaped CNP were synthesized by hydrothermal and ultrasonication methods, respectively. Physico-chemical characterization confirmed the shape of sphere and cube CNP and effect of various parameters on their particle size distribution and zeta potential. In vitro results revealed that sphere and cube CNP differentially modulated ROS and RNS levels in J774 macrophages. Specifically, cube CNP significantly reduced RSV-induced ROS levels without affecting RNS levels while sphere CNP increased RSV-induced RNS levels with minimal effect on ROS levels. Cube CNP drove an M1 phenotype in RSV-infected macrophages in vitro by increasing macrophage surface expression of CD80 and CD86 with a concomitant increase in TNFα and IL-12p70, while simultaneously decreasing M2 CD206 expression. Intranasal administration of sphere and cube-CNP were well-tolerated with no observed toxicity in BALB/c mice. Notably, cube CNP preferentially accumulated in murine alveolar macrophages and induced their activation, avoiding enhanced uptake and activation of other inflammatory cells such as neutrophils, which are associated with RSV-mediated inflammation. In conclusion, we report that sphere and cube CNP modulate macrophage polarization and innate cellular responses during RSV infection.
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  • 文章类型: Journal Article
    化学抗性以及由此产生的治疗失败在临床癌症治疗中是相当具有挑战性的。对化学抗性获得中的遗传变异的理解鼓励了使用基因调节方法来恢复抗癌药物的功效。许多智能纳米粒子被设计和优化以介导核酸和抗癌药物之间的组合治疗。这篇综述旨在定义这种共负载纳米载体的合理设计,目的是在各种细胞水平上逆转化学抗性,以改善抗癌治疗的治疗效果。通过治疗加载的原则,物理化学特性调整,和不同的纳米载体修饰,还研究了联合药物对化学敏感性恢复的有效性。到目前为止,这些新兴的纳米载体处于发展状态,但有望带来出色的成果。
    Chemoresistance and hence the consequent treatment failure is considerably challenging in clinical cancer therapeutics. The understanding of the genetic variations in chemoresistance acquisition encouraged the use of gene modulatory approaches to restore anti-cancer drug efficacy. Many smart nanoparticles are designed and optimized to mediate combinational therapy between nucleic acid and anti-cancer drugs. This review aims to define a rational design of such co-loaded nanocarriers with the aim of chemoresistance reversal at various cellular levels to improve the therapeutic outcome of anticancer treatment. Going through the principles of therapeutics loading, physicochemical characteristics tuning, and different nanocarrier modifications, also looking at combination effectiveness on chemosensitivity restoration. Up to now, these emerging nanocarriers are in development status but are expected to introduce outstanding outcomes.
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  • 文章类型: Journal Article
    未经批准:阿米替林是一种三环类抗抑郁药,用于治疗抑郁症。它记录了对不同组织的许多副作用。
    UNASSIGNED:从组织学和影像学上研究口服阿米替林对白化病大鼠牙周组织的反应。
    UNASSIGNED:将14只成年雄性白化病大鼠(150-200g)分为两组,控制和实验。实验组的大鼠通过口服管饲法接受10mg/kg/天的盐酸阿米替林,为期四周。准备下颌骨用于苏木精和伊红(H&E)和抗骨桥蛋白(抗OPN)免疫组织化学染色。在下颌牙槽骨中测量骨矿物质密度。使用独立样本t检验进行抗OPN和相对Hounsfield单位值(HU值)的统计分析。
    未经证实:实验组牙龈表现为上皮变性,伴有固缩核和固有层崩解。可见牙槽骨的分离区域和牙骨质某些区域的变性,牙周膜(PDL)厚度明显增加,并且在某些区域与骨和牙骨质脱离。实验组的免疫组织化学检查显示牙龈中的免疫阳性明显增加。牙骨质细胞,骨细胞,牙骨质,骨基质,与对照组相比,成纤维细胞和PDL纤维。统计分析显示,两组之间牙龈中的抗OPN面积百分比差异无统计学意义。与对照组相比,实验组其他牙周组织中的抗OPN面积%有统计学上的显着增加,而相对HU值却有统计学上的显着降低。
    UNASSIGNED:阿米替林对牙周组织具有破坏性作用,并在统计学上增加除牙龈外的所有牙周组织中Anti-OPN的表达,并降低骨矿物质密度。
    UNASSIGNED: Amitriptyline is a tricyclic antidepressant drug accustomed to treat depressive disorders. It recorded many side effects on different tissues.
    UNASSIGNED: To investigate reaction of Albino rats\' periodontium after oral administration of Amitriptyline histologically and radiographically.
    UNASSIGNED: Fourteen adult male albino rats (150-200 g) were divided into two groups, control and experimental. Rats of experimental group received 10 mg⁄kg⁄day of Amitriptyline hydrochloride by oral gavage for four weeks. Mandibles were prepared for hematoxylin and eosin (H&E) and anti-osteopontin (Anti-OPN) immunohistochemistry staining. Bone mineral density was measured in mandibular alveolar bone. Statistical analysis for Anti-OPN and relative Hounsfield unit value (HU value) was performed using independent-samples t-test.
    UNASSIGNED: Gingiva of experimental group showed epithelial degeneration with pyknotic nuclei and disintegration in lamina propria. Areas of separation in alveolar bone and degeneration of some regions in cementum were seen with apparent increase in periodontal ligament (PDL) thickness and its detachment from bone and cementum at some regions. Immunohistochemical examination of experimental group showed apparently increased immunopositivity in gingiva, cementocytes, osteocytes, cementum, bone matrices, fibroblasts and PDL fibers when compared to control group. Statistical analysis revealed insignificant difference of Anti-OPN area% in gingiva between both studied groups. While there was statistical significant increase of Anti-OPN area% in the other periodontium tissues and high statistical significant decrease of relative HU value in experimental group when compared to control.
    UNASSIGNED: Amitriptyline has destructive effect on periodontal tissues and statistically increases the expression of Anti-OPN in all periodontal tissues except gingiva and decreases bone mineral density.
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  • 文章类型: Journal Article
    未经证实:人骨髓来源的间充质干细胞(hBM-MSCs)是具有自我更新能力和多谱系分化的未分化细胞,对再生医学有益。纳米支架是用于骨修复和再生的新型材料。Nisin是一种益生元,可以增加干细胞的寿命和增殖。本研究试图为Nisin预处理后在聚-L-乳酸(PLLA)支架上骨髓间充质干细胞分化为骨细胞提供适当的策略。
    UNASSIGNED:通过测量钙,碱性磷酸酶,和定量测试,如实时PCR,吖啶橙,茜素红,冯·科萨,和其他人。
    UNASSIGNED:MTT试验结果表明,1日,MSCs预处理的Nisin益生元的最佳剂量为200IU/mL,3rd,文化的第五天实时PCR数据表明ALP的表达率,骨连蛋白,骨钙蛋白,在Nisin的存在下,我增加了胶原蛋白,而RUNX-2基因表达下降。此外,茜素红和VonKossa测试的结果,以及扫描电子显微镜(SEM),结果表明,用Nisin预处理的样品中的细胞增殖显着增加。
    UNASSIGNED:该研究得出结论,在PLLANano支架上用Nisin预处理的样品中,细胞增殖和分化增加。
    UNASSIGNED: Human bone marrow-derived mesenchymal stem cells (hBM-MSCs) are undifferentiated cells with self-renewing ability and multi-lineage differentiation beneficial for regenerative medicine. Nano scaffolds are novel materials employed in bone repair and regeneration. Nisin is a prebiotic that can increase stem cells\' lifespan and proliferation. This study attempted to provide a proper strategy for bone marrow mesenchymal stem cells differentiation into the Osteocytes on a Poly-L-lactic-acid (PLLA) scaffold after pretreating with Nisin.
    UNASSIGNED: MSC osteogenic differentiation was evaluated by measuring Calcium, Alkaline phosphatase, and quantitative tests such as Real-Time PCR, Acridine Orange, Alizarin Red, Von Kossa, and others.
    UNASSIGNED: The result of the MTT test showed that the optimal dose of Nisin prebiotic for the MSCs\' preconditioning was 200 IU/mL on the 1st, 3rd, and 5th days of culture. Real-time PCR data indicated that the expression rate of ALP, Osteonectin, Osteocalcin, and Collagen I have increased in the presence of Nisin, while the RUNX-2 gene expression has decreased. Furthermore, the results of Alizarin Red and Von Kossa tests, as well as Scanning electron microscopy (SEM), revealed that the cell proliferation in the preconditioned samples with Nisin increased significantly.
    UNASSIGNED: The study concluded that the cell proliferation and differentiation increased in samples pretreated with Nisin on the PLLA Nano scaffolds.
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  • 文章类型: Journal Article
    Fabry病是由GLA基因突变引起的X连锁糖脂贮积障碍,导致溶酶体酶α半乳糖苷酶A(AGA)缺乏。因此,糖脂底物Gb3在关键组织和器官中积累,产生进行性衰弱疾病。在法布里病中,高达80%的患者经历了难以治疗的终身神经性疼痛,并极大地影响了他们的生活质量。AGA缺乏导致神经性疼痛的分子机制尚不清楚。部分原因是缺乏可用于在细胞水平上研究潜在病理的体外模型。使用CRISPR-Cas9基因编辑,我们从人类胚胎干细胞系产生了两个GLA基因突变的克隆.我们的克隆细胞系保持了正常的干细胞形态和多能性标记,并显示了法布里病的表型特征,包括缺乏AGA活性和Gb3的细胞内积累。证实了GLA基因外显子1中预测位置的突变。使用已建立的双重SMAD抑制/WNT激活技术,我们能够证明我们缺乏AGA的克隆,以及野生型对照,可以分化为表达疼痛受体的外周型感觉神经元。这种遗传和生理相关的人体模型系统为研究法布里病周围神经病变的细胞机制提供了一种新的有前途的工具,并可能有助于开发新的治疗策略,以帮助减轻这种疾病的负担。
    Fabry disease is an X-linked glycolipid storage disorder caused by mutations in the GLA gene which result in a deficiency in the lysosomal enzyme alpha galactosidase A (AGA). As a result, the glycolipid substrate Gb3 accumulates in critical tissues and organs producing a progressive debilitating disease. In Fabry disease up to 80% of patients experience life-long neuropathic pain that is difficult to treat and greatly affects their quality of life. The molecular mechanisms by which deficiency of AGA leads to neuropathic pain are not well understood, due in part to a lack of in vitro models that can be used to study the underlying pathology at the cellular level. Using CRISPR-Cas9 gene editing, we generated two clones with mutations in the GLA gene from a human embryonic stem cell line. Our clonal cell lines maintained normal stem cell morphology and markers for pluripotency, and showed the phenotypic characteristics of Fabry disease including absent AGA activity and intracellular accumulation of Gb3. Mutations in the predicted locations in exon 1 of the GLA gene were confirmed. Using established techniques for dual-SMAD inhibition/WNT activation, we were able to show that our AGA-deficient clones, as well as wild-type controls, could be differentiated to peripheral-type sensory neurons that express pain receptors. This genetically and physiologically relevant human model system offers a new and promising tool for investigating the cellular mechanisms of peripheral neuropathy in Fabry disease and may assist in the development of new therapeutic strategies to help lessen the burden of this disease.
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  • 文章类型: Journal Article
    未经证实:HEV变种,例如Paslahepevirus种balayani(HEV-A)和大鼠HEV(Rocahepevirusratti;HEV-C1)中的猪基因型,可在免疫功能低下的个体中引起慢性戊型肝炎。很少有可靠和容易获得的小动物模型能够准确反映慢性HEV感染。我们旨在开发一种免疫受损的慢性戊型肝炎感染大鼠模型。
    未经证实:在这项动物模型感染研究中,用药物组合(泼尼松龙,他克莫司,和霉酚酸酯)通常由移植接受者服用。用源自人和大鼠的HEV-C1菌株或源自人的HEV-A菌株攻击大鼠。病毒载量,肝功能,肝脏组织学,幽默,监测细胞免疫反应。
    UNASSIGNED:与低剂量(LD)免疫抑制剂治疗和免疫活性(IC)大鼠的短暂感染相比,高剂量(HD)免疫抑制方案可持续延长大鼠的人和大鼠来源的HEV-C1感染(感染后长达12周)。粪便中平均HEV-C1病毒载量,血清,HD方案治疗的大鼠的肝组织高于LD或IC大鼠(p<0.05)。在慢性感染的大鼠中观察到丙氨酸转氨酶升高,这与肝组织中的组织学肝炎和HEV-C1抗原表达一致。无(0/6)的HD方案治疗,5/6LD方案治疗,和6/6IC大鼠在物种特异性免疫印迹中产生了针对HEV-C1的抗体。在HD方案治疗的大鼠中,免疫抑制的逆转与病毒血症的清除和HEV-C1特异性体液和细胞免疫反应的恢复有关。在接受治疗的慢性戊型肝炎患者中,通过i.p.利巴韦林治疗观察到病毒载量抑制的模拟模式。HD方案治疗的大鼠仍然不易感染HEV-A。
    UNASSIGNED:我们开发了一种可扩展的慢性戊型肝炎免疫抑制大鼠模型,该模型与移植受者的这种感染表型非常相似。
    UNASSIGNED:人类慢性戊型肝炎的研究需要方便的小动物模型。我们通过用人类常用的药物作为器官移植排斥预防来抑制大鼠的免疫反应,开发了慢性戊型肝炎的动物模型。该模型紧密地模仿了人类慢性戊型肝炎的特征。
    UNASSIGNED: HEV variants such as swine genotypes within Paslahepevirus species balayani (HEV-A) and rat HEV (Rocahepevirus ratti; HEV-C1) cause chronic hepatitis E in immunocompromised individuals. There are few reliable and accessible small animal models that accurately reflect chronic HEV infection. We aimed to develop an immunocompromised rat model of chronic hepatitis E infection.
    UNASSIGNED: In this animal model infection study, rats were immunosuppressed with a drug combination (prednisolone, tacrolimus, and mycophenolate mofetil) commonly taken by transplant recipients. Rats were challenged with human- and rat-derived HEV-C1 strains or a human-derived HEV-A strain. Viral load, liver function, liver histology, humoural, and cellular immune responses were monitored.
    UNASSIGNED: A high-dose (HD) immunosuppressive regimen consistently prolonged human- and rat-derived HEV-C1 infection in rats (up to 12 weeks post infection) compared with transient infections in low-dose (LD) immunosuppressant-treated and immunocompetent (IC) rats. Mean HEV-C1 viral loads in stool, serum, and liver tissue were higher in HD regimen-treated rats than in LD or IC rats (p <0.05). Alanine aminotransferase elevation was observed in chronically infected rats, which was consistent with histological hepatitis and HEV-C1 antigen expression in liver tissue. None (0/6) of the HD regimen-treated, 5/6 LD regimen-treated, and 6/6 IC rats developed antibodies to HEV-C1 in species-specific immunoblots. Reversal of immunosuppression was associated with clearance of viraemia and restoration of HEV-C1-specific humoural and cellular immune responses in HD regimen-treated rats, mimicking patterns in treated patients with chronic hepatitis E. Viral load suppression was observed with i.p. ribavirin treatment. HD regimen-treated rats remained unsusceptible to HEV-A infection.
    UNASSIGNED: We developed a scalable immunosuppressed rat model of chronic hepatitis E that closely mimics this infection phenotype in transplant recipients.
    UNASSIGNED: Convenient small animal models are required for the study of chronic hepatitis E in humans. We developed an animal model of chronic hepatitis E by suppressing immune responses of rats with drugs commonly taken by humans as organ transplant rejection prophylaxis. This model closely mimicked features of chronic hepatitis E in humans.
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  • 文章类型: Journal Article
    耻垢分枝杆菌单ADP-核糖基转移酶(Arr)的生理作用,使利福平失活,尚不清楚。较早的研究报道了在氧化应激和DNA损伤期间arr的表达增加。这表明Arr在细胞氧化状态中的作用及其对DNA损伤的相关作用。由于活性氧(ROS)影响氧化状态,我们调查了Arr是否影响耻垢分枝杆菌中的ROS水平。与野生型菌株(WT)相比,在arr敲除菌株(arr-KO)的对数中期(MLP)培养物中发现了明显升高的超氧化物和羟基自由基水平。arr-KO与基因组整合的arr在其天然启动子下的表达互补,恢复了与WT相当的ROS水平。由于活跃生长的ARR-KO中固有的高ROS水平,具有rpoB突变的利福平抗性可以在暴露于利福平0小时时选择,与WT不同的是,在利福平暴露的第12小时出现了抗性。活跃生长的arr-KO培养物的微阵列分析显示,琥珀酸脱氢酶I和NADH脱氢酶I操纵子的基因表达水平显着提高,这将导致超氧化物水平的增加。并行,特异性DNA修复基因的表达显著下降,有利于保留ROS造成的突变。几种代谢途径基因的表达也显著改变。这些观察结果表明,Arr是维持基因表达谱所必需的,该基因表达谱将在活跃生长的耻垢分枝杆菌中提供最佳水平的ROS和DNA修复系统。
    The physiological role of mono-ADP-ribosyl transferase (Arr) of Mycobacterium smegmatis, which inactivates rifampicin, remains unclear. An earlier study reported increased expression of arr during oxidative stress and DNA damage. This suggested a role for Arr in the oxidative status of the cell and its associated effect on DNA damage. Since reactive oxygen species (ROS) influence oxidative status, we investigated whether Arr affected ROS levels in M. smegmatis. Significantly elevated levels of superoxide and hydroxyl radical were found in the mid-log phase (MLP) cultures of the arr knockout strain (arr-KO) as compared those in the wild-type strain (WT). Complementation of arr-KO with expression from genomically integrated arr under its native promoter restored the levels of ROS equivalent to that in WT. Due to the inherently high ROS levels in the actively growing arr-KO, rifampicin resisters with rpoB mutations could be selected at 0 hr of exposure itself against rifampicin, unlike in the WT where the resisters emerged at 12th hr of rifampicin exposure. Microarray analysis of the actively growing cultures of arr-KO revealed significantly high levels of expression of genes from succinate dehydrogenase I and NADH dehydrogenase I operons, which would have contributed to the increased superoxide levels. In parallel, expression of specific DNA repair genes was significantly decreased, favouring retention of the mutations inflicted by the ROS. Expression of several metabolic pathway genes also was significantly altered. These observations revealed that Arr was required for maintaining a gene expression profile that would provide optimum levels of ROS and DNA repair system in the actively growing M. smegmatis.
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  • 文章类型: Journal Article
    心血管疾病是死亡的主要原因,血管损伤,心血管疾病的共同病理基础,与巨噬细胞凋亡和炎症反应密切相关。金雀异黄素,一种植物雌激素,发挥心血管保护作用,但是潜在的机制尚未完全阐明。在这项研究中,RAW264.7细胞用金雀异黄素处理,脂多糖(LPS),核因子-κB(NF-κB)抑制剂,和/或蛋白激酶B(AKT)激动剂,以确定染料木素在LPS刺激的细胞凋亡和炎症中的作用。同时,高脂饮食喂养的C57BL/6小鼠给予金雀异黄素以评价金雀异黄素对LPS诱导的心血管损伤小鼠模型的作用。这里,我们证明LPS通过促进miR-21的表达显著增加巨噬细胞的凋亡抵抗和炎症反应,miR-21通过靶向编码区下调肿瘤坏死因子-α诱导的蛋白8样2(TIPE2)表达。金雀异黄素通过抑制NF-κB降低miR-21表达,然后阻断Toll样受体4(TLR4)通路和依赖于TIPE2的AKT磷酸化,从而抑制LPS。我们的研究提示miR-21/TIPE2通路参与M1巨噬细胞凋亡和炎症反应,金雀异黄素通过NF-κB调节Vmp1的启动子区,在表观遗传水平上抑制LPS诱导的心血管损伤的进展。
    Cardiovascular diseases are a major cause of mortality, and vascular injury, a common pathological basis of cardiovascular disease, is deeply correlated with macrophage apoptosis and inflammatory response. Genistein, a type of phytoestrogen, exerts cardiovascular protective activities, but the underlying mechanism has not been fully elucidated. In this study, RAW264.7 cells were treated with genistein, lipopolysaccharide (LPS), nuclear factor-kappa B (NF-κB) inhibitor, and/or protein kinase B (AKT) agonist to determine the role of genistein in apoptosis and inflammation in LPS-stimulated cells. Simultaneously, high fat diet-fed C57BL/6 mice were administered genistein to evaluate the function of genistein on LPS-induced cardiovascular injury mouse model. Here, we demonstrated that LPS obviously increased apoptosis resistance and inflammatory response of macrophages by promoting miR-21 expression, and miR-21 downregulated tumor necrosis factor-α-induced protein 8-like 2 (TIPE2) expression by targeting the coding region. Genistein reduced miR-21 expression by inhibiting NF-κB, then blocked toll-like receptor 4 (TLR4) pathway and AKT phosphorylation dependent on TIPE2, resulting in inhibition of LPS. Our research suggests that miR-21/TIPE2 pathway is involved in M1 macrophage apoptosis and inflammatory response, and genistein inhibits the progression of LPS-induced cardiovascular injury at the epigenetic level via regulating the promoter region of Vmp1 by NF-κB.
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