209 resultados para Micrococcus -- immunology


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The diagnostic applicability of the Clonorchis sinensis recombinant 7-kDa protein was evaluated. In enzyme-linked immunosorbent assays and immunoblots, the protein showed high sensitivities (81.3 and 71.9%, respectively) and specificities (92.6 and 89.7%, respectively) for sera obtained from various helminthic infections. Some paragonimiasis sera showed cross-reactions. The antigen might be valuable in the serodiagnosis of human clonorchiasis.

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The potential use of poultry by-product meal (PBM) and meat and bone meal (MBM) as alternative dietary protein sources for juvenile Macrobrachium nipponense was studied by a 70-day growth trial. Triplicate groups of M. nipponense (initial body weight: 0.37 g) were fed at 20.7-22.4 degreesC on each of the five isoenergetic and isonitrogenous diets (protein content about 38%) with different replacement of fish meal by MBM or PBM. The control diet used white fish meal as the sole protein source, the other four diets were prepared with 15% or 50% fish meal protein substituted by either MBM (MBM15, MBM50) or PBM (PBM15, PBM50). The results showed that replacement of fish meal by MBM in diets did not affect growth performance of M. nipponense (P > 0.05), while specific growth rate in PBM15 was significantly higher than that in other groups (P < 0.05). Survival rates of shrimp fed with MBM15 diet were significantly higher than that in other groups (P < 0.05). No significant differences in immunological parameters, including total haemocyte count (THC), phenoloxidase activity (PO) and respiratory burst (O-2(-)), were observed between the shrimps that were fed five experimental diets, and all determined immunological parameters in control groups were slightly higher than those in replacement groups. In conclusion, either MBM or PBM investigated could replace up to 50% fish meal protein in diets for M. nipponense. (C) 2003 Elsevier Ltd. All rights reserved.

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UV-inactivated GCHV (grass carp hemorrhage virus) is able to induce an antiviral state in cultured CAB cells (crucian carp Carassius auratus blastulae embryonic cells) via the production of interferon (IFN). In the current work, the full-length cDNAs of two Mx genes, termed CaMx1 and CaMx2, have been cloned and sequenced from UV-inactivated GCHV-infected and still IFN-producing CAB cells by suppression subtractive hybridization. Their putative proteins show the characteristically structural features of mammalian IFN-induced Mx proteins, including GTP-binding motif, dynamin family signature and leucine zipper motif. CaMx1 exhibits 85% sequence identity to zebrafish MxA and 72-74% to three Atlantic salmon Mx proteins. CaMx2 is most similar to zebrafish MxE, with 80% identity, and then rainbow trout Mx3, with 52%. Constitutive expression was detected by RT-PCR for CaMx1, but not for CaMx2, in normal CAB cells, but their up-regulations could be induced after treatment with active GCHV, UV-inactivated GCHV and CAB IFN. Distinct kinetics of expression was observed for either CaMx1 or CaMx2 corresponding to the three stimuli, and even between CaMx1 and CaMx2, corresponding to the same stimulus. Upon virus infection, the transcriptional induction was strongly blocked for CaMx2 by cycloheximide (CHX), whereas almost nothing was observed for CaMx1. By contrast, following treatment with CAB IFN, CHX did not inhibit either gene transcription. Collectively, these results suggest that there are very distinct mechanisms for modulating the expression of both CaMx1 and CaMx2 in normal and GCHV-infected CAB cells.

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Type I interferon (IFN) exerts its pleiotropic effects mainly through the JAK-STAT signaling pathway, which is presently best described in mammals. By subtractive suppression hybridization, two fish signaling factors, JAK1 and STAT1, had been identified in the IFN-induced crucian carp Carassius auratus L. blastulae embryonic (CAB) cells after treatment with UV-inactivated grass carp hemorrhagic virus (GCHV). Further, the full-length cDNA of STAT1, termed CaSTAT1, was obtained. It contains 2926 bp and encodes a protein of 718 aa. CaSTAT1 is most similar to rat STAT1 with 59% identity overall and displays all highly conserved domains that the STAT family possesses. Like human STAT1beta, it lacks the C-terminus acting as transcriptional activation domain in mammals. By contrast, only a single transcript was detected in virus-induced CAB cells. Expression analysis showed that CaSTAT1 could be activated by stimulation of CAB cells with poly I:C, active GCHV, UV-inactivated GCHV or CAB IFN, and displayed diverse expression patterns similar to that of mammalian STATI. Additionally, the expression of an antiviral gene CaMx1 was also induced under the same conditions, and expression difference between CaSTAT1 and CaMx1 was revealed by induction of CAB IFN. These results provide molecular evidence supporting the notion that the fish IFN signaling transduction pathway is similar to that in mammals. Fish IFN exerts its multiple functions, at least antiviral action, through a JAK-STAT pathway. (C) 2004 Elsevier Ltd. All rights reserved.

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Interferon (IFN) can induce an antiviral state via interferon-regulatory transcription factors (IRFs), which bind to and control genes directed by the interferon-stimulated response element (ISRE). Here we describe a fish IRF, termed CaIRF7, cloned from a subtractive cDNA library which is constructed with mRNAs obtained from crucian carp (Carassius auratus L.) blastulae embryonic (CAB) cells infected by UV-inactivated GCHV and mock-infected cells. CaIRF7 cDNA was found to be 1816 bp in length, with a 42 bp 5' UTR and a 508 bp 3' UTR. The open reading frame translates into 421 amino acids in which a DNA-binding domain (DBD) containing the repeated tryptophan motif and IRFs association domain have been identified. Like chicken GgIRF3, CaIRF7 was most similar to mammalian IRF7 with 27 to 30% identity overall and some 37% identity in their DBDs. A single transcript of 1.9 kb was detected in virally induced CAB cells by virtual Northern blotting. RT-PCR analysis revealed a wide tissue distribution of CaIRF7 constitutive expression, with detectable transcript in non-infected CAB cells and various tissues of healthy crucian carp. In addition, CaIRF7 expression was differentially increased by stimulation of the CAB cells with active GCHV, UV-inactivated GCHV or CAB IFN, indicating that the activation of CaIRF7 was directly regulated by IFN. (C) 2003 Published by Elsevier Ltd.

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Immunoglobulin light chain cDNA sequences of a perciform fish, the mandarin fish Siniperca chuatsi were amplified from head kidney mRNA by reverse transcription (RT)-PCR and RACE methods using degenerated primer and gene specific ones. In cDNA sequences of the VL region, nucleotide exchanges were present mainly within CDRs, although a lesser degree of variability was also found in FRs. Moreover, the length of CDRI and CDR3 in the mandarin fish is shorter than in most other fish species. In the middle of S. chuatsi CL region, a microsatellite sequence (AGC)(6-8) was found, which is also present in another perciform species, the spotted wolffish (Anarhichas minor). The comparison of amino acid sequence of the mandarin fish CL domain with those of other vertebrates showed the highest degree of similarity of 94.5% to the spotted wolffish, while the similarity with rainbow trout (Oncorhynchus mykiss) Ig L1 (62.7%) and channel catfish (Ictalurus punctatus) Ig LG (55.9%) isotypes is also higher. However, there is only 50% identity in the VL regions between the mandarin fish and the wolffish. The sequence similarity of the mandarin fish CL domain with those of higher vertebrate did not readily allow it to be classified as kappa or lambda isotype. The phylogenetic analyses also demonstrated that the CL genes of the mandarin fish and most other teleost fish cluster as a separate branch out of the mammal kappa and lambda branches. (C) 2003 Elsevier B.V. All rights reserved.

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An antibody phage display library against White Spot Syndrome Virus (WSSV) was constructed. After four rounds of panning against WSSV, 192 out of 480 clones displayed WSSV binding activity. One of the positive clones, designated A1, had relatively higher activity specifically binding to WSSV A1-soluble, single-chain fragment variable (scFv) antibody has an affinity constant (K-aff) of 2.02 +/- 0.42 x 10(9) M-1. Dot blot assays showed that A1-soluble scFv could detect WSSV directly from shrimp hemolymph after 24-h feeding infection by WSSV. A1 scFv has potential for the development of a cheap, simple and sensitive diagnostic kit for WSSV in the field. (C) 2003 Elsevier Science B.V. All rights reserved.

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therapeutic drugs, vaccines and mechanisms of human diseases. Little is known about the normal levels of leukocyte subpopulations of Chinese rhesus macaques. To obtain these data, 100 blood samples from Chinese rhesus macaques were collected. The normal range of major leukocyte subpopulations, such as T lymphocytes, B lymphocytes, monocytes, myeloid dendritic cells (mDCs) and plasmacytoid dendritic cells (pDCs), were quantitatively analyzed by flow cytometry through BD trucount tubes. The influence of age and sex on the cell counts of leukocyte subpopulations was analyzed. The counts of CD3+ T cells, CD3+CD4+ T cells, CD3+CD8+ T cells and B cells decreased with age, but those of monocytes, mDCs and pDCs had no significant correlation with age. Significant differences existed in the cell counts of most leukocyte subpopulations between the male and female groups except pDCs. Furthermore the values of the females were higher than those of the males. The study provided basic information about the leukocyte subpopulations of Chinese rhesus macaques, and it may be valuable for immunobiological study of Chinese rhesus macaques. Cellular & Molecular Immunology. 2009;6(6):433-440.

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Many B cell epitopes within p24 of human immunodeficiency virus type 1 (HIV-1) were identified, while most of them were determined by using murine monoclonal antibodies reacting with overlapping peptides of p24. Therefore these epitopes may not represent the actual epitopes recognized by the HIV-1 infected individuals. In the present study, immune responses of 67 HIV-1 positive sera from Yunnan Province, China to five peptides on p24 of HIV-1 and one of HIV-2 were analyzed. All of 67 sera did not recognize peptide GA-12 on HIV-1 and peptide AG-23 on HIV-2, which indicated that GA-12 was not human B cell epitope and AG-23 did not cross-react with HIV-1 positive serum. Except 13 sera (19.4%), all remaining sera did not recognize peptides NI-15, DR-16, DC-22 and PS-18, which indicated that these four peptides represented B cell linear epitopes of HIV-1 p24 in some HIV-1 infected individuals but not the immuno-dominant epitopes in most individuals. Cellular & Molecular Immunology. 2005;2(4):289-293.

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抗菌肽是一类具有强大杀菌能力的肽类分子,同时还具有离子调节、免疫调节、蛋白酶抑制剂和自由基清除等其他生物活性。现已鉴定的抗菌肽超过1,200 种,几乎存在于所有生物种类中。在抗生素耐受严重的今天,抗菌肽极有潜力成为新型的有效抗菌药物,许多抗菌肽已进入临床前研究或临床研究。在本论文中,我们选择了无指盘臭蛙(Odorrana grahami)来源的三种抗菌肽(Brevinin 2E-OG1、Nigrocin-OG4 和Palustrin-OG1),单独或组合使用,以藤黄微球菌(Micrococcus luteus)、枯草芽孢杆菌(Bacillus subtilis)和白假丝酵母菌(Candida albicans)为研究对象,进行微生物对抗菌肽耐受性的实验诱导;并通过检测胞外蛋白酶活性、蛋白质组学等方法对微生物耐受抗菌肽机制进行初步的研究。将微生物培养于含有低浓度抗菌肽(单独使用或组合使用)培养基中,每日转接一次,每十次酌情提高抗菌肽浓度。80 次转接后,除藤黄微球菌未对 Palustrin-OG1 产生耐受外,其余所有的实验菌株均表现出对所用三种抗菌肽的耐受。但是Palustrin-OG1 与Brevinin 2E-OG1 或Nigrocin-OG4 联合使用能在一定程度上降低耐受性。将诱导后细菌于不含抗菌肽条件下培养,转接5 次后,对耐受现象无影响,说明这种耐受是可以稳定遗传的。抗菌肽耐受机制之一是分泌蛋白酶水解胞外抗菌肽,我们通过两种方式检测胞外蛋白酶活性,一种是检测发酵液的酪蛋白水解活性,另一种是检测发酵液处理抗菌肽后对抗菌活性的影响。结果发现枯草芽孢杆菌和藤黄微球菌发酵液存在着蛋白酶活性,推测胞外蛋白酶可能与二者对抗菌肽的耐受有关;而白假丝酵母菌发酵液中未检测到蛋白酶活性。另外,我们还通过蛋白质组学的手段对枯草芽孢杆菌耐受机制进行了初步的研究,鉴定了5 个差异表达的蛋白,表达上调的蛋白有yraA(功能未知)、Tpx (巯基过氧化物酶,Thiol peroxidase)、pdhD(二氢硫辛酰胺脱氢酶,dihydrolipoamide dehydrogenase),表达下调的有cotN/TasA(芽孢膜相关蛋白,spore coat-associated protein)和gapA(三磷酸甘油醛脱氢酶,Glyceraldehyde 3-phosphate dehydrogenase 1 ,GAPDH)。yraA 和Tpx 都由Spx 调控,yraA 可以水解小肽增加自由氨基酸,而自由氨基酸增多时gapA、tasA 表达水平会下降,Spx 是由sigma-M 因子调控的,所以我们推测sigma-M 因子在B. subtiis 对抗菌肽耐受中起到了重要的作用。总之,本研究发现抗菌肽的联合作用会减缓微生物对其耐受的程度,为抗菌肽类药物研发提供了一种新思路;同时对抗菌肽耐受机制的初步研究也为今后的深入研究打下了基础。另外,我们还设计了一种新型的抗菌肽系统命名方法,并构建了昆明动物研究所抗菌肽数据库。

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本文主要研究了泸州老窖古酿酒作坊内外环境空气真菌和空气细菌的群落结构和分布特征。结果如下: 作坊内外环境空气微生物浓度差别显著,并随季节变换而变化,春、夏季微生物浓度较高,秋、冬季较低,空气真菌在夏季达到最高,细菌在春季最高。 古作坊内外环境检测到的真菌均为16 属,但优势菌属不同,作坊外的优势菌属为青霉属(Penicillium)、曲霉属(Aspergillus)、无孢菌(non-sporing)、枝孢霉属(Cladosporium)和链格孢属(Alternaria);而作坊内优势菌属为曲霉属、青霉属、酵母菌(Yeast)、无孢菌,作坊内还含有较高浓度的根霉属(Rhizopus)、毛霉属(Mucor)、短梗霉属(Aureobasidiu),枝孢霉属和链格孢属等,曲霉属、酵母菌、根霉属、毛霉属为古酿酒作坊重要的酿酒真菌,青霉属、链格孢属为酿酒不利菌群。对古作坊内曲霉属进行了初步鉴定,主要是小冠曲霉(A.cristatellus)、米曲霉(A.oryzae)、黑曲霉(A.niger)和白曲霉(A.cadidus)。 空气细菌10 属21 种,作坊内外环境的优势菌属均为芽孢杆菌属(Bacillus)、微球菌属(Micrococcus)、葡萄球菌属(Staphylococcus)、假单胞菌属(Pseudomonad),其中芽孢杆菌属在作坊内占有绝对的优势,浓度比在40℅以上,是古酿酒作坊重要的酿酒细菌,另外还检测到较高浓度的乳酸杆菌(lactobucillus),这类菌容易使酒味发涩发苦,为酿酒不利菌。 作坊内外环境空气微生物表现出明显的交流现象。作坊内,青霉属、枝孢霉属、链格孢属、葡萄球菌属等杂菌占有一定比例;而在作坊外,芽孢杆菌属、曲霉属、根霉属(Rhizopus)、酵母菌等处于相对较高水平,绿化环境较好的营沟头作坊内的短梗霉属,枝孢霉属和链格孢属等杂菌含量低于什字头和新街子作坊。 The community structure and distribution characteristic of airborne microbes was investigated in ancient brewage workshops of luzhoulaojiao. The results are as follows: The concentration of airborne microbes was different in interior and exterior environment of ancient workshops, and also varied by seasons. microbial concentration was higher in spring and summer, and lower in fall and winner. The highest levels of airborne bacteria was in spring, but the fungal’s in summer. The identified genus of fungi were 16 in interior and exterior environment of the ancient workshops. But the dominant genus were different , The advantage genus in the interior were Aspergillus, Yeasts, Penicillum and Nonsporing and in the exterior were Penicillum, Nonsporing, Cladosporium, Aspergillus and Aureobasidiu. Rhizopus ,mucor, Aureobasidiu, Cladosporium, Alternaria and all also were at a higher level. Among these, Aspergillus, Yeasts, Rhizopus ,mucor are important vintage flora . Penicillum, Alternaria do harm to vintage. Aspergillus of ancient workshops was identified , the preponderant aspergillus species were A.cristatellus, A.oryzae, A.niger and A.cadidus in ancient brewage workshops. 10 genus 21 species bacteria were identified, the advantage genuses among the interior and exterior of the three workshops were bacillus, microccus, Staphylococcus Pseudomonas. Bacillus, which account for beyond 40℅ of the total bacteria concentration in all sampling pots, was the most dominant genus. Lactobacillus was identified at a high level in ancient workshops, it makes spirit taste bitter and astringent. So it is not a kind of good bacterium for vintage. The fungus in the interior and exterior atmosphere characterized intercommunion phenomenon. Obviously, the concentration of profitless fungus such as Penicillum, Cladosporium, Alternaria appeared in the interior, and the fungus such as Bacillus, Aspergillus, Rhizopus and Yeasts in the exterior were at a relatively high level. the harmfull fungus in yinggoutou workshops such as Aureobasidiu, Cladosporium, Alternaria and all were lower than shenzitou and xinjiezi workshops.

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Combination of affinity extraction procedures with mass spectrometric analyses is termed affinity-directed mass spectrometry, a technique that has gained broad interest in immunology and is extended here with several improvements from methods used in previous studies. A monoclonal antibody was immobilized on a nitrocellulose (NC) membrane, allowing the corresponding antigen to be selectively captured from a complex solution for analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). This method was also used to rapidly determine the approximate binding region responsible for the antibody/antigen interaction. The tryptic fragments of antigen protein in buffer were applied to the antibody immobilized on NC film and allowed to interact. The NC film was then washed to remove salts and other unbound components, and subjected to analysis by MALDI-TOFMS. Using interferon-alpha (2a) and anti-interferon-alpha (2a) monoclonal antibody IgG as a model system, we successfully extracted the antigen protein and determined the approximate binding region for the antigen/antibody interaction (i.e., the tryptic fragment responsible). Copyright (C) 2001 John Wiley & Sons, Ltd.