溃疡性结肠炎小鼠肠道通透性改变与TNF-α及NF-κB P65的关系

目的：采用2.5%葡聚糖硫酸钠（DSS）定量灌胃诱导小鼠溃疡性结肠炎（UC）,观察小鼠结肠通透性改变与肿瘤坏死因子α（TNF-α）及NF-κB p65的关系。方法：48只ICR小鼠随机分为2组（n=24）：对照组和模型组。模型组小鼠给予2.5% DSS定量灌胃诱发小鼠急性UC,对照组小鼠予同体积的蒸馏水灌胃代替。记录两组小鼠疾病活动指数（DAI）,9 d后测定两组小鼠结肠组织病理学评分、结肠通透性、TNF-α及NF-κB p65。统计分析DAI、结肠通透性、TNF-α与NF-κB p65之间的相关性。结果：与对照组比较,模型组小鼠DAI、结肠病理学评分、结肠通透性、TNF-α、NF-κB p65均显著增高（P均<0.01）。小鼠DAI增高与结肠通透性密切相关（P均<0.01）,结肠通透性增高与TNF-α、NF-κB p65密切相关（P均<0.01）。结论：与对照组小鼠相比,DSS造模小鼠的结肠通透性显著增高,并与TNF-α、NF-κB p65增高呈正相关。TNF-α、NF-κB p65增高导致结肠通透性增高,进而导致炎症免疫反应过度增强,可能是UC发病的重要环节。     

乳酸调控大鼠肠黏膜微血管内皮细胞的NF-κB信号通路

目的探讨内毒素（LPS）刺激大鼠肠黏膜微血管内皮细胞（RIMMVECs）后,乳酸（LA）调控NF-κB信号通路中磷酸化IκBα和NF-κB p65蛋白表达情况,肿瘤坏死因子α（TNF-α）和白细胞介素6（IL-6）mRNA表达情况,阐明乳酸发挥作用的最佳时间及其调控NF-κB信号通路的部位。方法提取RIMMVECs总蛋白和总RNA,用Western blotting检测NF-κB p65、IκBα及p-IκBα蛋白表达水平,用real-time PCR对TNF-α和IL-6 mRNA进行定量检测。结果乳酸能降低LPS诱导RIMMVECs分泌的TNF-α和IL-6 mRNA表达水平,并分别于24 h和3 h下调效果最明显;乳酸能抑制IκBα磷酸化及NF-κB转录活性,并于4～8 h达到最佳效果;乳酸发挥作用部位是抑制信号通路中IκBα磷酸化。结论乳酸通过抑制IκBα磷酸化而阻断NF-κB的激活,抑制下游炎性因子表达,进而发挥出很好的预防炎症效果。     

NF-κB启动的炎症反应在小鼠侵袭性肺曲霉病肺损伤中的作用

为了探讨NF-κB启动的炎症反应在小鼠侵袭性肺曲霉病肺损伤中的作用,将小鼠分3组:正常组、正常 烟曲霉菌接种组、IPA模型组,小鼠鼻吸入烟曲霉菌第4天处死,取肺组织,肺组织切片经HE染色观察病理损伤;比色法测定肺组织MPO活性;免疫组化法评价肺组织NF-κBp65蛋白的活化:RT-PCR法检测肺组织TNF-α、IFN-γ和β-tublin mRNA的表达. 结果显示,正常健康组小鼠肺组织结构正常,未见炎症发生;正常 烟曲霉菌接种组小鼠肺组织有炎症细胞浸润,未见孢子萌芽;IPA模型组小鼠的肺组织病理损伤严重,可见炎症细胞浸润,孢子萌芽生成菌丝.正常 烟曲霉菌接种组和IPA模型组小鼠肺组织的TNF-α和IFN-γ mRNA的相对表达水平、NF-κB p65免疫组化评分和MPO活性均高于正常组小鼠(P<0.05):并且IPA模型组小鼠肺组织NF-κB p65免疫组化评分值和MPO活性均高于正常 烟曲霉菌接种组(P<0.05).结果提示,烟曲霉菌感染可激活小鼠肺组织NF-κB介导的炎症信号通路,诱导下游TNF-α和IFN-γ的表达,募集大量的中性粒细胞于感染组织,是导致IPA小鼠肺组织严重病理损伤的因素之一.     

TNF-α诱导的NF-κB慢病毒报告基因系统的构建

目的:构建一种肿瘤坏死因子α(TNF-α)诱导的NF-κB慢病毒报告基因系统。方法:以NF-κB信号通路为基础,设计并构建含有NF-κB响应元件和mCherry报告基因序列的表达载体,并进一步建立受NF-κB调控表达mCherry的细胞株,最后使用TNF-α进行刺激验证。结果:质粒经过双酶切鉴定,得到约1500 bp的目的片段,符合预计大小且测序分析正确,表明质粒构建成功;在TNF-α刺激实验中,NF-κB信号通路的刺激物TNF-α作用于构建的NF-κB调控表达mCherry荧光蛋白的细胞株后出现特异性荧光反应,TNF-α诱导组的细胞有较强的mCherry表达,阳性率约为90%,而未加TNF-α组细胞mCherry阳性表达率约为10%。结论:构建了受NF-κB调控稳定表达mCherry的慢病毒报告基因系统,可用于对NF-κB活化效果的检测及筛选,具有普适性的应用价值。     

miRNA-9-5p与NF-κB信号通路在2型糖尿病肾病发病中的作用机制

目的:探讨mi RNA-9-5p与NF-κB信号通路在2型糖尿病肾病发病中的作用机制。方法:将80只db/db小鼠随机分为糖尿病肾病组、糖尿病肾病+罗格列酮组、糖尿病肾病+mi RNA-9-5p组、糖尿病肾病+阴性对照组,每组20只,分别给予生理盐水、噻唑烷二酮类抗糖尿病药马来酸罗格列酮、mi RNA-9-5p、mi RNA-9-5p阴性对照核酸,10μg/d腹腔注射。另将20只健康db/m小鼠作为对照组。观察各组空腹血糖(FBG)、餐后血糖(PBG)、肾脏指数、24h尿量、肾脏组织变化,检测血清NF-κB信号通路关键因子单核细胞趋化因子蛋白-1(MCP-1)、肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6),及肾脏组织NF-κB m RNA、NF-κB p65蛋白水平。结果:糖尿病肾病组FBG、PBG、24 h尿量均高于对照组,肾脏指数低于对照组(P0.05)。糖尿病肾病+罗格列酮组和糖尿病肾病+mi RNA-9-5p组小鼠FBG、PBG、24 h尿量低于糖尿病肾病组,肾脏指数高于糖尿病肾病组(P0.05)。糖尿病肾病组小鼠血清MCP-1、TNF-α、IL-6水平,肾脏组织NF-κB m RNA、NF-κB p65蛋白水平均高于对照组(P0.05)。糖尿病肾病+罗格列酮组和糖尿病肾病+mi RNA-9-5p组血清MCP-1、TNF-α、IL-6水平,肾脏组织NF-κB m RNA、NF-κB p65蛋白水平低于糖尿病肾病组(P0.05)。结论:NF-κB在糖尿病肾病发病中起到重要作用,mi RNA-9-5p可以阻断NF-κB信号通路,下调MCP-1、TNF-α、IL-6的表达,抑制糖尿病肾病的发生和发展。     

当归对阴虚哮喘小鼠气道黏液高分泌及TNF-α/NF-κB信号通路的影响*

目的: 探讨当归对阴虚哮喘小鼠气道黏液高分泌及TNF-α/NF-κB信号通路的影响。方法: 取KM小鼠随机分为空白对照组、模型对照组、氨溴索组、当归低、中、高剂量(2、4、8 g/kg)组(n=12),采用卵蛋白与甲状腺片复制阴虚哮喘模型,观测当归对小鼠哮喘症状、IgE、TNF-α以及肺组织Muc5ac与NF-κB表达的影响。结果: 2、4、8 g/kg当归能明显缓解阴虚哮喘小鼠的哮喘症状,降低血清IgE与BALF中TNF-α水平,抑制肺组织Muc5ac与NF-κB的过度表达。结论: 当归具有明显的平喘作用,抑制TNF-α/NF-κB信号通路而缓解气道黏液高分泌是其平喘的作用机制之一。     

黄芩苷对脂多糖诱导的巨噬细胞NF-κB活化和炎症因子表达的影响

目的:研究黄芩苷对脂多糖(LPS)诱导小鼠巨噬细胞核因子κB(NF-κB)及肿瘤坏死因子α(TNF-α)、白介素6(IL-6)表达的影响.方法:分别用LPS(终浓度1μgomL-1)和LPs+黄芩苷(终浓度10,50,100μmol moloL-1)处理生长良好的小鼠巨噬细胞RAW264.7,用RT-PCR法和Elisa法检测细胞及其上清液中TNF-α、IL-6 mRNA和蛋白的表达变化,用Western Blot法检测细胞核内NF-κB p65蛋白含量变化.结果:LPS刺激RAW264.7细胞可导致NF-κB激活,上调TNF-α、IL-6表达;黄芩苷预处理能降低LPS诱导的NF-κB出活化和TNF-α、IL-6表达.结论:黄芩苷可通过抑制NF-κB活化,下调LPS诱导的巨噬细胞TNF-α、IL-6的生成,发挥抗炎作用.这可能是其抗动脉粥样硬化的作用机制之一.     

银杏叶提取物对内毒素诱导巨噬细胞核因子-κB活化及炎性细胞因子表达的调节

探讨银杏叶提取物（EGb761）对内毒素（LPS）诱导RAW264．7细胞核因子-κB（NF-κB）活化及炎性细胞因子基因表达的调节,为银杏叶提取物的临床运用提供理论依据．分别用LPS或EGb761＋LPS处理体外培养的小鼠巨噬细胞系RAW264．7细胞,采用蛋白质印迹分析检测细胞中NF-κB活性,用逆转录-聚合酶链反应（RT-PCR）和酶联免疫吸附法（ELISA）检测细胞中TNF-α、IL-1β、IL-6 mRNA和蛋白的表达．研究结果表明LPS组NF-κB活性和TNF-α、IL-1β、IL-6含量在刺激后2～12h明显高于正常对照组,而EGb761＋LPS组NF-κB活性和TNF-α、IL-1β、IL-6含量均显著低于LPS组．结果提示LPS可诱导RAW264．7细胞NF-κB活化,导致TNF-α、IL-1β、IL-6基因表达增强,而EGb761能抑制NF-κB活化而调节TNF-α、IL-1β、IL-6基因的表达．     

Foreign exploration for Scirtothrips perseae Nakahara (Thysanoptera: Thripidae) and associated natural enemies on avocado (Persea americana Miller)

Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Biological control of three floating water weeds,<Emphasis Type="Italic">Eichhornia crassipes,Pistia stratiotes</Emphasis>, and <Emphasis Type="Italic">Salviniamolesta</Emphasis> in the Republic of Congo

Since 1999, four specific weevils (Coleoptera, Curculionidae) were released in the Republic of Congo against three exotic floating water weeds: Neochetina eichhorniae Warner and N. bruchi Hustache against water hyacinth, Neohydronomus affinis Hustache against water lettuce, and Cyrtobagous salviniae Calder and Sands against water fern. Recoveries of exotic weevils were made from all 24 release sites except one, and all four species have established and spread (up to 800 km for water hyacinth weevils). Within a few years of releases, control of water fern and water lettuce was such that fishing and navigation could be resumed, while reductions of water hyacinth populations were only beginning.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.     

Demographic characteristics of an intertidal bay goby (Lepidogobius lepidus)

Synopsis In a fourteen month study (May 1976 – June 1977) I examined the following characteristics of an intertidal bay goby (Lepidogobius lepidus) in Morro Bay, California, U.S.A.: annual and seasonal patterns of abundance, age composition and growth rates, survivorship and mortality patterns, and the reproductive cycle for female gobies. Fishes were collected with the aid of quinaldine and otoliths and ovaries removed. Age and growth rates were estimated from otolith annuli using a back calculation formula and a Brody-Bertalanffy growth curve. Mortality rates were derived using the methods of Heincke (1913), Robson & Chapman (1960), mean age, and a catch curve (Ricker 1975). A gonad index was used to describe the annual reproductive cycle. Results indicated that abundance fluctuated seasonally and that these fluctuations appeared to be caused by reproductive emigrations. Bay gobies reached an age of 7+ and a standard length of 87 mm. Growth was relatively constant (6 mm yr⁻¹) until age 5, at which point it began to decline. The mean rates of survivorship, mortality, and instantaneous mortality were 0.75, 0.25, and 0.29 respectively. Mortality rates for individual age classes ranged from 0.13 to 0.51 and increased with age. This stock appears to reproduce mainly during the winter.     

Die GattungKarschia — Bindeglied zwischen bitunicaten Ascomyceten und lecanoralen Flechtenpilzen?

The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.

     

Systematic significance of mature embryo of bamboos

The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.