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41.
42.
Gene expression cascades in pancreatic development 总被引:28,自引:0,他引:28
43.
Liu R Cai J Hu X Tan M Qi Y German M Rubenstein J Sander M Qiu M 《Development (Cambridge, England)》2003,130(25):6221-6231
During early neural development, the Nkx6.1 homeodomain neural progenitor gene is specifically expressed in the ventral neural tube, and its activity is required for motoneuron generation in the spinal cord. We report that Nkx6.1 also controls oligodendrocyte development in the developing spinal cord, possibly by regulating Olig gene expression in the ventral neuroepithelium. In Nkx6.1 mutant spinal cords, expression of Olig2 in the motoneuron progenitor domain is diminished, and the generation and differentiation of oligodendrocytes are significantly delayed and reduced. The regulation of Olig gene expression by Nkx6.1 is stage dependent, as ectopic expression of Nkx6.1 in embryonic chicken spinal cord results in an induction of Olig2 expression at early stages, but an inhibition at later stages. Moreover, the regulation of Olig gene expression and oligodendrogenesis by Nkx6.1 also appears to be region specific. In the hindbrain, unlike in the spinal cord, Olig1 and Olig2 can be expressed both inside and outside the Nkx6.1-expressing domains and oligodendrogenesis in this region is not dependent on Nkx6.1 activity. 相似文献
44.
Bisignano G Sanogo R Marino A Aquino R D'Angelo V Germanò MP De Pasquale R Pizza C 《Letters in applied microbiology》2000,30(2):105-108
The antimicrobial activity of a methanol extract and isolated constituents of Mitracarpus scaber, a species used in folk medicine by West African native people, was evaluated against Staphylococcus aureus and Candida albicans strains. The mitracarpus methanol extract possesses both antibacterial and antimycotic activities (minimum inhibitory concentration-MIC 31.25 and 62.50 microg ml-, respectively). This extract was subsequently fractioned and monitored by bioassays leading to the isolation of seven compounds screened for antibacterial and antimycotic activities. Among these compounds, gallic acid and 3,4,5-trimethoxybenzoic acid inhibited the growth of Staph. aureus (MIC 3.90 and 0.97 microg ml-). 4-Methoxyacetophenone and 3,4,5-trimethoxyacetophenone effectively inhibited C. albicans (MIC 1.95 microg ml-). The other compounds (kaempferol-3-O-rutinoside, rutin and psoralen) which were also isolated showed low antibacterial and antimycotic activities (125-500 microg ml-). 相似文献
45.
German Z Chambliss KL Pace MC Arnet UA Lowenstein CJ Shaul PW 《The Journal of biological chemistry》2000,275(11):8183-8189
Nitric oxide (NO) plays an important role in airway function, and endothelial NO synthase (eNOS) is expressed in airway epithelium. To determine the basis of cell-specific eNOS expression in airway epithelium, studies were performed in NCI-H441 human bronchiolar epithelial cells transfected with the human eNOS promoter fused to luciferase. Transfection with 1624 base pairs of sequence 5' to the initiation ATG (position -1624) yielded a 19-fold increase in promoter activity versus vector alone. No activity was found in lung fibroblasts, which do not express eNOS. 5' deletions from -1624 to -279 had modest effects on promoter activity in H441 cells. Further deletion to -248 reduced activity by 65%, and activity was lost with deletion to -79. Point mutations revealed that the GATA binding motif at -254 is mandatory for promoter activity and that the positive regulatory element between -248 and -79 is the Sp1 binding motif at -125. Electrophoretic mobility shift assays yielded two complexes with the GATA site and three with the Sp1 site. Immunodepletion with antiserum to GATA-2 prevented formation of the slowest migrating GATA complex, and antiserum to Sp1 supershifted the slowest migrating Sp1 complex. An electrophoretic mobility shift assay with H441 versus fibroblast nuclei revealed that the slowest migrating GATA complex is unique to airway epithelium. Thus, cell-specific eNOS expression in airway epithelium is dependent on the interaction of GATA-2 with the core eNOS promoter, and the proximal Sp1 binding site is also an important positive regulatory element. 相似文献
46.
José C. Aponte Abraham J. Vaisberg Denis Castillo German Gonzalez Yannick Estevez Jorge Arevalo Miguel Quiliano Mirko Zimic Manuela Verástegui Edith Málaga Robert H. Gilman Juan M. Bustamante Rick L. Tarleton Yuehong Wang Scott G. Franzblau Guido F. Pauli Michel Sauvain Gerald B. Hammond 《Bioorganic & medicinal chemistry》2010,18(8):2880-2886
The synthesis of 2-(5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimidin-4-yl)hydrazone-derivatives (BTPs) and their in vitro evaluation against Trypanosoma cruzi trypomastigotes, Mycobacterium tuberculosis, Leishmania amazonensis axenic amastigotes, and six human cancer cell lines is described. The in vivo activity of the most active and least toxic compounds against T. cruzi and L. amazonensis was also studied. BTPs constitute a new family of drug leads with potential activity against infectious diseases. Due to their drug-like properties, this series of compounds can potentially serve as templates for future drug-optimization and drug-development efforts for use as therapeutic agents in developing countries. 相似文献
47.
Roni Gilad Karen Meir Ilan Stein Larissa German Eli Pikarsky Nicola J. Mabjeesh 《PloS one》2015,10(4)
Septins are a family of GTP-binding cytoskeleton proteins expressed in many solid tumors. Septin 9 (SEPT9) in particular was found overexpressed in diverse carcinomas. Herein, we studied the expression of SEPT9 isoform 1 protein (SEPT9_i1) in human prostate cancer specimens. We utilized immunohistochemical staining to study the expression of SEPT9_i1 protein. Staining level was analyzed in association with clinical characteristics and the pathological Gleason grade and score. Fifty human prostate cancer specimens (42 primary tumors and 8 metastatic lesions) were stained by SEPT9_i1 antibody and analyzed. SEPT9_i1 protein was expressed in prostate cancer cells but absent in normal epithelial cells. The intensity of staining was correlated proportionally to pretreatment prostate-specific antigen (PSA) blood levels and Gleason score (P < 0.05). SEPT9_i1 was highly expressed in all metastatic lesions. A significant assocation between SEPT9_i1 expression and high Gleason score on multivariate linear regression analysis was found. We conclude that SEPT9_i1 is expressed in high-grade prostate tumors suggesting it has a significant role in prostate tumorigenesis and that it could serve as a molecular marker for prostate tumor progression. 相似文献
48.
49.
Kornelius Schulze Tobias J. Weismüller Michael Bubenheim Peter Huebener Roman Zenouzi Henrike Lenzen Christian Rupp Daniel Gotthardt Philipp de Leuw Andreas Teufel Vincent Zimmer Florian P. Reiter Christian Rust Lars Tharun Alexander Quaas S?ren A. Weidemann Frank Lammert Christoph Sarrazin Michael P. Manns Ansgar W. Lohse Christoph Schramm German PSC Study Group 《PloS one》2015,10(10)
Background & Aims
Current guidelines recommend immunosuppressive treatment (IT) in patients with primary sclerosing cholangitis (PSC) and elevated aminotransferase levels more than five times the upper limit of normal and elevated serum IgG-levels above twice the upper limit of normal. Since there is no evidence to support this recommendation, we aimed to assess the criteria that guided clinicians in clinical practice to initiate IT in patients with previously diagnosed PSC.Methods
This is a retrospective analysis of 196 PSC patients from seven German hepatology centers, of whom 36 patients had received IT solely for their liver disease during the course of PSC. Analyses were carried out using methods for competing risks.Results
A simplified autoimmune hepatitis (AIH) score >5 (HR of 36, p<0.0001) and a modified histological activity index (mHAI) greater than 3/18 points (HR 3.6, p = 0.0274) were associated with the initiation of IT during the course of PSC. Of note, PSC patients who subsequently received IT differed already at the time of PSC diagnosis from those patients, who did not receive IT during follow-up: they presented with increased levels of IgG (p = 0.004) and more frequently had clinical signs of cirrhosis (p = 0.0002).Conclusions
This is the first study which investigates the parameters associated with IT in patients with PSC in clinical practice. A simplified AIH score >5 and a mHAI score >3, suggesting concomitant features of AIH, influenced the decision to introduce IT during the course of PSC. In German clinical practice, the cutoffs used to guide IT may be lower than recommended by current guidelines. 相似文献50.
Esmaeil Ebrahimie Mohammad Reza Naghavi Abdolhadi Hosseinzadeh Mohammad Reza Behamta Manijeh Mohammadi-Dehcheshmeh Ahmad Sarrafi German Spangenberg 《Plant Cell, Tissue and Organ Culture》2007,90(3):293-311
In this study, using cumin embryo as explant and manipulating plant growth regulators (PGRs) in regeneration medium, the main
in vitro morphogenesis pathways including direct shoot organogenesis, direct somatic embryogenesis, indirect somatic embryogenesis,
and indirect shoot organogenesis were obtained. The effects of PGRs, subculture, and light on the induction and progression
of different pathways were studied in detail. Direct shoot organogenesis occurred on the meristematic zone, while direct somatic
embryogenesis was observed on hypocotyl part of cumin embryo (more differentiated part). Application of BAP (0.1 mgl−1) was the sole triggering factor for induction of callus and indirect regeneration pathways. Exogenous IAA played the central
role in the direct somatic embryogenesis pathway; however, the combined effects of IAA and NAA along with the high endogenous
cytokinin level resulted in direct shoot organogenesis. Subculturing revealed accelerating effects on direct somatic embryogenesis
pathway and callus formation. Conversely, subculturing had negative effect on direct shoot organogenesis pathway. In certain
combinations of PGRs, like 0.4 mgl−1 IAA + 0.4 mgl−1 NAA, co-induction and co-regeneration of different pathways were observed. Investigation of genotype dependencies of different
pathways showed that direct pathways are more genotype-dependent, stable, and faster than indirect pathways. This research
presents the embryo of cumin as a convenient model material for induction and comparison of different morphogenesis pathways. 相似文献