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141.
Stefano Scabini Edoardo Rimini Emanuele Romairone Renato Scordamaglia Luigi Vallarino Veronica Giasotto Carlo Ferro Valter Ferrando 《World journal of surgical oncology》2009,7(1):1-3
Background
Synchronous midgut carcinoids with gastrointestinal adenocarcinoma are a rare but recognised association.Case presentation
The patient, a 74 year old woman, underwent anterior resection for a low rectal adenocarcinoma. Intra-operatively 3 serosal deposits of tumour were noted in the distal ileum. Histology revealed these to be ileal carcinoids.Conclusion
During resection of a gastrointestinal tumour, a thorough inspection of the abdominal cavity should be undertaken to investigate the possibility of metastatic secondaries or a synchronous tumour as is reported in this case. 相似文献142.
143.
Siderophore production confers to bacteria competitive advantages to colonize plant tissues and to exclude other microorganisms
from the same ecological niche. This work shows that the community of endophytic siderophore-producing bacteria (SPB) associated
to Oryza sativa cultivated in Uruguayan soils is dynamic and diverse. These bacteria were present in grains, roots, and leaves, and their
density fluctuated between log10 3.44 and log10 5.52 cfu g−1 fresh weight (fw) during the plant growth. Less than 10% of the heterotrophic bacteria produced siderophores in roots and
leaves of young plants, but most of the heterotrophic bacteria were siderophore-producers in mature plants. According to their
amplified restriction DNA ribosomal analysis (ARDRA) pattern, 54 of the 109 endophytic SPB isolated from different plant tissues
or growth stages from replicate plots, were unique. Bacteria belonging to the genera Sphingomonas, Pseudomonas, Burkholderia, and Enterobacter alternated during plant growth, but the genus Pantoea was predominant in roots at tillering and in leaves at subsequent stages. Pantoea ananatis was the SPB permanently associated to any of the plant tissues, but the genetic diversity within this species—revealed by
BOX-PCR fingerprinting- showed that different strains were randomly distributed along time and plant tissue, suggesting that
a common trait of the species P. ananatis determined the interaction with the rice plant. Several isolates were stronger IAA producers than Azospirillum brasilense or Herbaspirillum seropedicae. In vitro inhibition assays showed that SPB of the genus Burkholderia were good antagonists of pathogenic fungi and that only one SPB isolate of the genus Pseudomonas was able to inhibit A. brasilense and H. seropedicae. These results denoted that SPB were selected into the rice plant. P. ananatis was the permanent and dominant associated species which was unable to inhibit two of the relevant plant growth-promoting
bacteria. 相似文献
144.
We present BioGraph, a data integration and data mining platform for the exploration and discovery of biomedical information.
The platform offers prioritizations of putative disease genes, supported by functional hypotheses. We show that BioGraph can
retrospectively confirm recently discovered disease genes and identify potential susceptibility genes, outperforming existing
technologies, without requiring prior domain knowledge. Additionally, BioGraph allows for generic biomedical applications
beyond gene discovery. BioGraph is accessible at . 相似文献
145.
Di Paolo JA Huang T Balazs M Barbosa J Barck KH Bravo BJ Carano RA Darrow J Davies DR DeForge LE Diehl L Ferrando R Gallion SL Giannetti AM Gribling P Hurez V Hymowitz SG Jones R Kropf JE Lee WP Maciejewski PM Mitchell SA Rong H Staker BL Whitney JA Yeh S Young WB Yu C Zhang J Reif K Currie KS 《Nature chemical biology》2011,7(1):41-50
Bruton's tyrosine kinase (Btk) is a therapeutic target for rheumatoid arthritis, but the cellular and molecular mechanisms by which Btk mediates inflammation are poorly understood. Here we describe the discovery of CGI1746, a small-molecule Btk inhibitor chemotype with a new binding mode that stabilizes an inactive nonphosphorylated enzyme conformation. CGI1746 has exquisite selectivity for Btk and inhibits both auto- and transphosphorylation steps necessary for enzyme activation. Using CGI1746, we demonstrate that Btk regulates inflammatory arthritis by two distinct mechanisms. CGI1746 blocks B cell receptor-dependent B cell proliferation and in prophylactic regimens reduces autoantibody levels in collagen-induced arthritis. In macrophages, Btk inhibition abolishes FcγRIII-induced TNFα, IL-1β and IL-6 production. Accordingly, in myeloid- and FcγR-dependent autoantibody-induced arthritis, CGI1746 decreases cytokine levels within joints and ameliorates disease. These results provide new understanding of the function of Btk in both B cell- or myeloid cell-driven disease processes and provide a compelling rationale for targeting Btk in rheumatoid arthritis. 相似文献
146.
Analía I Alet Diego H Sánchez Alejandro Ferrando Antonio F Tiburcio Ruben Alcazar Juan Cruz Cuevas Teresa Altabella Francisco Marco Pico Pedro Carrasco Ana B Menéndez Oscar A Ruiz 《Plant signaling & behavior》2011,6(2):237-242
Salt stress has been frequently studied in its first osmotic phase. Very often, data regarding the second ionic phase is missing. It has also been suggested that Putrescine or/and Spermine could be responsible for salt resistance. In order to test this hypothesis under long-term salt stress, we obtained Arabidopsis thaliana transgenic plants harboring pRD29A::oatADC or pRD29A::GUS construction. Although Putrescine was the only polyamine significantly increased after salt acclimation in pRD29A::oatADC transgenic lines, this rendered in no advantage to this kind of stress. The higher Spermine levels found in WT and transgenic lines when compared to control conditions along with no increment on Putrescine levels in WT plants under salt acclimation, leads us to analyze Spermine effect on pADC1 and pADC2 expression. Increasing levels of this polyamine inhibits these promoters expression while enhances pRD29A expression, making Spermine the polyamine responsible for salt acclimation, and the transgenic lines developed in this work suitable for studying Putrescine roles in conditions where its biosynthesis would be inhibited in the WT genotype.Key words: arginine decarboxilase, salt acclimation, polyamines, putrescine, spermine, salt overlay sensitive mutants 相似文献
147.
D Bagga N Singh S Modi P Kumar D Bhattacharya ML Garg S Khushu 《Journal of biosciences》2013,38(5):905-915
Neuropsychological studies have shown that alcohol dependence is associated with neurocognitive deficits in tasks requiring memory, perceptual motor skills, abstraction and problem solving, whereas language skills are relatively spared in alcoholics despite structural abnormalities in the language-related brain regions. To investigate the preserved mechanisms of language processing in alcohol-dependents, functional brain imaging was undertaken in healthy controls (n=18) and alcohol-dependents (n=16) while completing a lexical semantic judgment task in a 3 T MR scanner. Behavioural data indicated that alcohol-dependents took more time than controls for performing the task but there was no significant difference in their response accuracy. fMRI data analysis revealed that while performing the task, the alcoholics showed enhanced activations in left supramarginal gyrus, precuneus bilaterally, left angular gyrus, and left middle temporal gyrus as compared to control subjects. The extensive activations observed in alcoholics as compared to controls suggest that alcoholics recruit additional brain areas to meet the behavioural demands for equivalent task performance. The results are consistent with previous fMRI studies suggesting compensatory mechanisms for the execution of task for showing an equivalent performance or decreased neural efficiency of relevant brain networks. However, on direct comparison of the two groups, the results did not survive correction for multiple comparisons; therefore, the present findings need further exploration. 相似文献
148.
In response to hypoxia, tissues have to implement numerous mechanisms to enhance oxygen delivery, including the activation of angiogenesis. This work investigates the angiogenic response of the hypoxic caudate putamen after several recovery times. Adult Wistar rats were submitted to acute hypoxia and analysed after 0 h, 24 h and 5 days of reoxygenation. Expression of hypoxia-inducible factor-1 alfa (HIF-1α) and angiogenesis-related genes including vascular endothelial growth factor (VEGF), adrenomedullin (ADM) and transforming growth factor-beta 1 (TGF-β1) was determined by both RT-PCR and ELISA. For vessel labelling, lectin location and expression were analysed using histochemical and image processing techniques (fractal dimension). Expression of Hif-1α, Vegf, Adm and Tgf-β1 mRNA rose immediately after hypoxia and this increase persisted in some cases after 5 days post-hypoxia. While VEGF and TGF-β1 protein levels increased parallel to mRNA expression, ADM remained unaltered. The quantification of the striatal vessel network showed a significant augmentation at 24 h of reoxygenation. These results reveal that not only short-term hypoxia, but also the subsequent reoxygenation period, up-regulate the angiogenic pathway in the rat caudate putamen as a neuroprotective mechanism to hypoxia that seeks to maintain a proper blood supply to the hypoxic tissue, thereby minimizing the adverse effects of oxygen deprivation. 相似文献
149.
Di Salvo Luciana P. Ferrando Lucía Fernández-Scavino Ana García de Salamone Inés E. 《Plant and Soil》2018,424(1-2):405-417
Plant and Soil - Azospirillum brasilense is one of plant growth promoting bacteria used to improve plant growth and grain yield of cereal crops. The level of inoculation response is defined by... 相似文献
150.
Loss of meiosis in Aspergillus 总被引:2,自引:0,他引:2
If strictly mitotic asexual fungi lack recombination, the conventional view
predicts that they are recent derivatives from older meiotic lineages. We
tested this by inferring phylogenetic relationships among closely related
meiotic and strictly mitotic taxa with Aspergillus conidial (mitotic)
states. Phylogenies were constructed by using DNA sequences from the
mitochondrial small ribosomal subunit, the nuclear ribosomal internal
transcribed spacers, and the nuclear 5.8S ribosomal gene. Over 920 bp of
sequence was analyzed for each taxon. Phylogenetic analysis of both the
mitochondrial and nuclear data sets showed at least four clades that
possess both meiotic and strictly mitotic taxa. These results support the
hypothesis that strictly mitotic lineages arise frequently from more
ancient meiotic lineages with Aspergillus conidial states. Many of the
strictly mitotic species examined retained characters that may be vestiges
of a meiotic state, including the production of sclerotia, sclerotium-like
structures, and hulle cells.
相似文献