Antagonistic activity

Study on the antagonistic activity against two pathogenic bacteria in humans (Staphylococcus aureus and Streptococcus pneumoniae) of the Streptomyces MIP_L26 (Called MIP_L26), isolated from the soil in the root zone of the May Chang tree; to investigate the biological characteristics of MIP_L26.

6p vipanly 28-10-2024 0 0   Download

In this study, experiments were performed to identify and screen Streptomyces strains that are antagonistic to Aeromonas hydrophila, which causes hemorrhagic disease in fishes. Among 80 isolates, 3 strains capable of antagonizing Aeromonas hydrophila by the agar diffusion plate method were obtained.

8p vibecca 01-10-2024 2 1   Download

In this study, 64 isolates of Streptomyces were screened for their antibacterial activity against Erwinia spp. The results indicated that 18 isolates showed an antagonistic reaction against Erwinia spp. Among them, isolate D5.1 showed the highest inhibition activity.

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The dominant isolates and isolates with broad-spectrum antagonistic activity were identified by 16S rRNA-based sequence analysis. Results showed that colony counts, total number of species, and the number of bioactive species of actinobacteria in saxicolous lichens were higher in elevation 3000 m. The dominant isolates were classified into 42 species of 10 genera. Antagonistic activities were detected in approximately 66% of the actinobacteria isolates.

7p sontrang95949594 23-02-2019 43 1   Download

The octadecaneuropeptide (ODN; QATVGDVNTDRPG LLDLK) and its C-terminal octapeptide (OP; RPGLLDLK), which exert anxiogenic activity, have been previously shown to increase intracellular calcium concentration ([Ca21]i) in cultured rat astrocytes through activation of a metabotropic receptor positively coupled to phospholipase C. It has also been found that the [D -Leu5]OP analog possesses a weak antagonistic activity. The aim of the present study was to synthesize and characterize cyclic analogs of OP and [D -Leu5]OP.

13p system191 01-06-2013 32 4   Download

TheDrosophila melanogasterprotein sprouty is induced uponfibroblast growth factor (FGF)- andepidermal growth factor (EGF)-receptor tyrosine kinase activation and acts as an inhibitor of the ras/MAP kinase pathway downstreamof these receptors. By differential displayRT-PCRof activated vs. resting umbilical artery smooth muscle cells (SMCs) we detected a new human sprouty gene, which we designated human sprouty 4 (hspry4) based on its homology with murine sprouty 4.

11p research12 29-04-2013 45 2   Download

Defining how the agonist–receptor interaction differs from that of the antagonist–receptor and understanding the mechanisms of receptor activation are fundamental issues in cell signalling. The V1a vasopressin receptor (V1aR) is a member of a family of related G-protein coupled receptors that are activated by neurohypophysial peptide hormones, including vasopressin (AVP). It has recently been reported that anarginyl in the distalN-terminus of theV1a Riscritical for binding agonists but not antagonists....

8p fptmusic 12-04-2013 28 2   Download

Trichodermaspecies have been investigated as biological control agents for over 70 years owing to their ability to antagonize plant pathogenic fungi. Mycoparasitism, one of the main mechanisms involved in the antagonistic activity ofTrichodermastrains, depends on the secretion of complex mix-tures of hydrolytic enzymes able to degrade the host cell wall. The antifun-gal activity of an a-1,3-glucanase (EC 3.2.1.59, enzymes able to degrade a-1,3-glucans and also named mutanases) has been described in T. harzia-num and its role in mycoparasitic processes has been suggested....

0p awards 05-04-2013 43 4   Download

Lipopolysaccharide (LPS) from the outer membrane of Gram-negative bac-teria belongs to the most potent activators of the mammalian immune sys-tem. Its lipid moiety, lipid A, the ‘endotoxic principle’ of LPS, carries two negatively charged phosphate groups and six acyl chain residues in a defined asymmetric distribution (corresponding to synthetic compound 506). Tetraacyl lipid A (precursor IVa or synthetic 406), which lacks the two hydroxylated acyl chains, is agonistically completely inactive, but is a strong antagonist to bioactive LPS when administered to the cells before LPS addition. .

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Thrombopoietin is the primary regulator of platelet production. We exploi-ted two naturally occurring miniproteins of the inhibitor cystine knot fam-ily as stable and rigid scaffolds for the incorporation of peptide sequences that have been shown to act as high-affinity thrombopoietin antagonists. Several miniproteins that antagonistically block thrombopoietin-mediated receptor activation were identified using a microscale reporter assay.

10p inspiron33 23-03-2013 32 4   Download

a-Conotoxins from marine snails are known to be selective and potent competitive antagonists of nicotinic acetylcholine receptors. Here we des-cribe the purification, structural features and activity of two novel toxins, SrIA and SrIB, isolated fromConus spuriuscollected in the Yucatan Chan-nel, Mexico.

14p galaxyss3 21-03-2013 50 5   Download

One of several potential approaches to study mechanisms of action of bio-logically active compounds is to develop their agonists and antagonists. In the present study, we report the identification of the first known molecule antagonizing the activity of the plant hormone cytokinin at the receptor level.

10p vinaphone15 27-02-2013 33 2   Download

The regulation of cytokines and pro-inflammatory genes is an absolute essentiality to combat inflammatory diseases. The present study investigated the effects of 4-O-chloroacetyl-2,3-di-O-acetyl-6-O-levulinoyl-b-d-glucopyr-anosyl]-(1-3)-1-O-(p-methoxyphenyl)-2-deoxy-2-N-trichloroacetyl-4,6-O-ben-zylidene-a-d-glucopyranoside (RSCL-0409), a novel small molecule Toll-like receptor (TLR) signalling antagonist, and its mechanism of action in human monocytic (THP-1) cells stimulated with lipopolysaccharide (LPS)....

14p mobifone23 18-01-2013 38 4   Download

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành y đề tài: Potent anti-inflammatory and antinociceptive activity of the endothelin receptor antagonist bosentan in monoarthritic mice...

9p thulanh16 22-10-2011 57 4   Download

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành y đề tài: The active metabolite of leflunomide, A77 1726, increases the production of IL-1 receptor antagonist in human synovial fibroblasts and articular chondrocytes...

9p thulanh11 11-10-2011 42 5   Download

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành y đề tài: Platelet-Activating Factor Antagonists Decrease Follicular Dendritic-Cell Stimulation of Human B Lymphocytes...

9p thulanh10 09-10-2011 48 2   Download

Neuroleptics (An thần kinh) · Là thuật ngữ được 2 nhà tâm thần học người Pháp là Jean Delay và Pierre Deniker đưa ra từ đầu những năm 50 · Là thuật ngữ hàm ý nhấn mạnh tác động trên hoạt tính tâm thần vận động (Psychomotor activity). · Vẫn được dùng phổ biến trong tâm thần học hiện nay. 2. Trên lâm sàng và y văn còn nhiều tên gọi khác nữa: · Antipsychotic: Thuốc chống loạn thần · Dopamine receptor antagonists: Thuốc đối vận receptor dopamin. · Major transquilizers: Thuốc bình thần mạnh · Antischizophrenia: Thuốc chữa TTPL. · Ataractics: Thuốc chống...

17p thiuyen7 26-08-2011 104 9   Download

Neuroleptics (An thần kinh) · Là thuật ngữ được 2 nhà tâm thần học người Pháp là Jean Delay và Pierre Deniker đưa ra từ đầu những năm 50 · Là thuật ngữ hàm ý nhấn mạnh tác động trên hoạt tính tâm thần vận động (Psychomotor activity). · Vẫn được dùng phổ biến trong tâm thần học hiện nay. 2. Trên lâm sàng và y văn còn nhiều tên gọi khác nữa: · Antipsychotic: Thuốc chống loạn thần · Dopamine receptor antagonists: Thuốc đối vận receptor dopamin. · Major transquilizers: Thuốc bình thần mạnh · Antischizophrenia: Thuốc chữa...

8p truongthiuyen19 08-08-2011 139 14   Download

Solid Tumors Small-molecule epidermal growth factor (EGF) antagonists act at the ATP binding site of the EGF receptor tyrosine kinase. In early clinical trials, gefitinib showed evidence of responses in a small fraction of patients with non-small cell lung cancer. Side effects were generally acceptable, consisting mostly of rash and diarrhea. Gefitinib was found to have antitumor activity mainly in the subset of patients with tumors containing activating mutations in the EGF receptor.

5p konheokonmummim 03-12-2010 80 4   Download

Estrogen receptors (ERs) and androgen receptors, members of the steroid hormone family of nuclear receptors, are targets of inhibition by drugs used to treat breast and prostate cancers, respectively. Tamoxifen, a partial agonist and antagonist of ER function, can mediate tumor regression in metastatic breast cancer and can prevent disease recurrence in the adjuvant setting, saving thousands of lives each year. Tamoxifen binds to the ER and modulates its transcriptional activity, inhibiting activity in the breast but promoting activity in bone and uterine epithelium.

5p konheokonmummim 03-12-2010 78 5   Download