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901.
902.
K Asakura Y Izumi Y Yamauchi S Nakatsuka M Inoue H Yashiro T Abe Y Sato H Nomori 《PloS one》2012,7(8):e42043
Objective
A risk of tumor seeding after percutaneous needle biopsy has been reported in various organs, including the lung. This study retrospectively evaluated the proportion of ipsilateral pleural recurrence after computed tomography-guided needle biopsy (CTNB) in p-stage I lung cancer patients.Methods
Of the 321 patients diagnosed with p-stage I lung cancer, 124 underwent CTNB before surgery, while 197 underwent non-CTNB procedures, including bronchoscopic biopsy in 188 patients and thoracoscopic wedge resection in 9. These patients were retrospectively analyzed.Results
While the tumor size was significantly larger in the non-CTNB group (25±9 mm) in comparison to the CTNB group (19±9 mm) (p<0.001), percentage of pleural, vascular, or lymphatic invasions were comparable between the two groups. Eight patients developed ipsilateral pleural recurrences, one (1%) in the CTNB group, and 7 (4%) in the non-CTNB group. Of these, 3 patients developed pleural recurrence only at first, 1 (1%) in the CTNB group, and 2 (1%) in the non-CTNB group. The differences in the proportions of these pleural recurrences between the 2 groups were not significant. Subgroup analyses by baseline characteristics such as tumor size, pT stage, or microscopic pleural invasion, showed that proportions of pleural recurrences in CTNB group were not high compared with non-CTNB group in each subgroup. Analysis of progression-free survival showed that recurrences in CTNB were not high compared with non-CTNB.Conclusions
The pleural recurrence was not significantly increased after CTNB in p-stage I lung cancer patients in this particular study. 相似文献903.
Graça-de Souza VK Monteiro-Góes V Manque P Souza TA Corrêa PR Buck GA Ávila AR Yamauchi LM Pinge-Filho P Goldenberg S Krieger MA Yamada-Ogatta SF 《Biological research》2010,43(2):233-241
The genus Phytomonas comprises trypanosomatids that can parasitize a broad range of plant species. These flagellates can cause diseases in some plant families with a wide geographic distribution, which can result in great economic losses. We have demonstrated previously that Phytomonas serpens 15T, a tomato trypanosomatid, shares antigens with Trypanosoma cruzi, the agent of human Chagas disease. Herein, two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) were used to identify proteins of P. serpens 15T that are recognized by sera from patients with Chagas disease. After 2D-electrophoresis of whole-cell lysates, 31 peptides were selected and analyzed by tandem mass spectrometry. Twenty-eight polypeptides were identified, resulting in 22 different putative proteins. The identified proteins were classified into 8 groups according to biological process, most of which were clustered into a cellular metabolic process category. These results generated a collection of proteins that can provide a starting point to obtain insights into antigenic cross reactivity among trypanosomatids and to explore P. serpens antigens as candidates for vaccine and immunologic diagnosis studies. 相似文献
904.
905.
Locus of a histidine-based, stable trifunctional, helix to helix collagen cross-link: stereospecific collagen structure of type I skin fibrils 总被引:1,自引:0,他引:1
The loci of the three amino acid residues that contribute their prosthetic groups to form the stable, nonreducible, trifunctional intermolecular cross-link histidinohydroxylysinonorleucine in skin collagen fibrils were identified. Two apparently homogeneous three-chained histidinohydroxylysinonorleucine cross-linked peptides were chromatographically isolated. They were obtained from a tryptic digest of denatured unreduced 6 M guanidine hydrochloride insoluble bovine skin collagen. Amino acid and sequence analyses demonstrated that the prosthetic groups of alpha 1(I)-chain Hyl-87, alpha 1(I)-chain Lys-16c, and alpha 2(I)-chain His-92 formed the cross-link. The latter results served to define the locus of the stable, nonreducible trifunctional moiety. Identical types of analyses were performed on the three-chained peptides isolated after bacterial collagenase digestion of the cross-linked tryptic peptides. This confirmed the initial identification and location of the three peptides linked by the cross-link. In addition, data reported here provide for a correction of the micromolecular structure for the alpha 2(I) chain. Stereochemical considerations concerning this trifunctional cross-link's specific locus indicate that the steric relationships between the alpha chains of skin and skeletal tissue collagens are fundamentally different and the intermolecular relationships in skin fibrils are specific for skin. The same molecular relationships also indicate that histidinohydroxylysinonorleucine links three molecules of collagen. The stereochemistry of cross-linking for skin collagen is in accordance with and explains the X-ray findings of a 65-nm periodicity found for this tissue [Stinson, R. H., & Sweeny, P. R. (1980) Biochim. Biophys. Acta 621, 158; Brodsky, B., Eikenberry, E. F., & Cassidy, K. (1980) Biochim. Biophys. Acta 621, 162]. 相似文献
906.
907.
T Shibasaki M Hotta N Yamauchi A Masuda T Imaki H Demura N Ling K Shizume 《Endocrinologia japonica》1987,34(6):799-807
Desensitization of rat pituitary somatotrophs to human growth hormone-releasing factor (hGHRF) was investigated using cultured rat anterior pituitary cells. Growth hormone (GH) release decreased but the production of cAMP was still induced in response to subsequently added 10(-9) M hGHRF from cells pretreated with hGHRF at concentrations ranging from 10(-11) to 10(-7) M for 4 h. Desensitization to 10(-9) M hGHRF was also observed in cells pretreated with 10(-9) M hGHRF for 4 h in the presence of 2 mM EGTA, 10 ng/ml nifedipine or 10(-9) M somatostatin-28, which decreased GH release during pretreatment. Forskolin and A23187, at concentrations of 10(-6) M and 10(-4) M, respectively, stimulated GH release from cells pretreated with hGHRF to the same extent as that from the control cells. These results, therefore, suggest that desensitization to GHRF occurs regardless of the presence of releasable GH pool and that some changes such as uncoupling of GHRF receptors with adenylate cyclase and decreased sensitivity to cAMP of cAMP-dependent protein kinase of the secretory mechanism of GH, in addition to the decrease in releasable GH pool and down regulation of GHRF receptors, may be involved in the desensitization mechanism. 相似文献
908.
Rat brainstem tryptophan 5-monooxygenase was activated about 2-fold by rat brain calcium-dependent regulator (CDR) protein. The activation required both ATP and Mg2+ in the presence of low concentrations of Ca2+. 相似文献
909.
Brain corticotropin-releasing factor acts as inhibitor of stress-induced gastric erosion in rats 总被引:1,自引:0,他引:1
T Shibasaki N Yamauchi M Hotta A Masuda H Oono I Wakabayashi N Ling H Demura 《Life sciences》1990,47(11):925-932
Gastric lesions are known to be caused by stress. Corticotropin-releasing factor (CRF) is a key peptide initiating various stress response. This study was designed to investigate how brain CRF is involved in the occurrence of stress-induced gastric erosion in rats. Intracerebroventricular (icv) administration of CRF suppressed the occurrence of gastric erosion induced by water-immersion restraint stress, and its suppressive effect was blocked by coadministration of a CRF receptor antagonist in rats. The peripheral administration of CRF had no influence on the occurrence of erosion. The icv administration of a CRF receptor antagonist or anti-rat CRF gamma-globulin increased gastric erosion induced by the stress. Ganglionic blockade with chlorisondamine, muscarinic blockade with atropine, or bilateral adrenalectomy by itself significantly inhibited the occurrence of stress-induced gastric erosion, and no additional effect of CRF on these treatments-induced inhibition of erosion was found. These results, therefore, suggest that the occurrence of stress-induced gastric erosion is mediated by the autonomic nervous system- and adrenal-dependent pathway, and that brain CRF reduces the occurrence of stress-induced gastric lesions by acting on its specific receptor within the central nervous system, probably through the autonomic nervous system- and adrenal-dependent mechanism. 相似文献
910.
Efficient transformation of phytopathogenic strains of Xanthomonas species. 总被引:1,自引:1,他引:0
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Efficient transformation and conjugation systems for use in phytopathogenic strains of Xanthomonas species were developed with a dual-function plasmid vector, pBXC12, which was constructed from a newly isolated Xanthomonas citri plasmid, pXCL6, and pBR328. By using this system, pBR328 could also transform the same strains of Xanthomonas. The systems make useful cloning vectors for the study of genes involved in the plant pathogenesis of this species. 相似文献