Cutting balloon-associated hemodialysis fistula rupture after failed standard balloon angioplasty.
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Biomedical subjects
Publications and source records attributed to R Murakami.
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BACKGROUND AND PURPOSE: On diffusion-weighted imaging (DWI), metastatic tumors of the brain may exhibit different signal intensities (SI) depending on their histology and cellularity. The purpose of our study was to verify the hypotheses (1) that SI on DWI predict the histology of metastases and (2) that apparent diffusion coefficient (ADC) values reflect tumor cellularity. MATERIALS AND METHODS: We assessed conventional MR images, DWI, and ADC maps of 26 metastatic brain lesions from 26 patients, 13 of whom underwent surgery after the MR examination. Two radiologists performed qualitative assessment by consensus of the SI on DWI in areas corresponding to their enhancing portions. We measured the contrast-to-noise ratio (CNR) on T2-weighted images and normalized ADC (nADC) values, and compared them with tumor cellularity. RESULTS: The mean SI on DWI and the CNR on T2-weighted images were significantly lower in well differentiated than in poorly differentiated adenocarcinomas and lesions other than adenocarcinoma. The mean nADC value was significantly higher in well differentiated than poorly differentiated adenocarcinomas and lesions other than adenocarcinoma. All 3 small-cell carcinomas and 1 large-cell neuroendocrine carcinoma exhibited high SI on DWI. The nADC value showed a significant inverse correlation with tumor cellularity. There was no significant correlation between the CNR and tumor cellularity. CONCLUSION: The SI on DWI may predict the histology of metastases; well differentiated adenocarcinomas tended to be hypointense, and small- and large-cell neuroendocrine carcinomas showed hyperintensity. Their ADC values reflect tumor cellularity.
NF-kappaB plays a pivotal role in pathogenesis in general arthritis. However, the participation of NF-kappaB in inflammation of the temporomandibular joint (TMJ) is poorly understood. We examined NF-kappaB expression in rat TMJs with synovitis induced by condyle hypermobility. By immunohistochemistry, NF-kappaB immunoreactivity was found mainly in the cytoplasm, not the nucleus, of the synovial lining cells of induced-synovitis and control TMJs. Southwestern histochemistry, a new method for detecting transcription factors, showed greater NF-kappaB expression in the nucleus of the synovial lining cells in the hypertrophic synovium than in control synovium. Increased numbers of the synovial lining cells with immunoreactivity for inducible nitric oxide synthase (iNOS), which is transcriptionally regulated by NF-kappaB, were also seen in the inflamed synovium. These findings indicate that excess mechanical stress increases NF-kappaB activation in the TMJ and suggest that active NF-kappaB is involved in the progression of TMJ inflammation.
PURPOSE: To clarify the effect of the contrast medium iopamidol on endothelial function and response of vasoactive peptide, as measured by changes in the levels of plasma endothelin, nitric oxide and atrial natriuretic peptide. MATERIAL AND METHODS: Thirteen patients received iopamidol 300 mg I/ml intra-arterially during routine abdominal angiography. The mean volume of contrast medium administered was 208.1+/-32.5 ml. Endothelin, nitric oxide and atrial natriuretic peptide were measured before and after angiography. RESULTS: Endothelin levels increased significantly (from 1.45+/-0.12 pg/ml to 1.90+/-0.10 pg/ml) after exposure to contrast medium. Nitric oxide levels decreased significantly (from 34.56+/-2.23 micromol/ to 25.43+/-1.83 micromol/l). Atrial natriuretic peptide levels increased significantly (from 11.43+/-1.68 pg/ml to 21.28+/-2.89 pg/ml). CONCLUSION: Exposure to contrast medium in humans is associated with an increase in plasma endothelin levels and a decrease in nitric oxide levels, and atrial natriuretic peptide levels also increase following CM injection.
Propeptides of papain-like cysteine proteinases such as papain, cathepsins B, L and S are potent inhibitors of their cognate cysteine proteinases with Ki values in the nanomolar range, and they exhibit highest inhibition selectivity for enzymes from which they originate. Recent studies have identified novel inhibitor proteins that are homologous to the proregions of papain-like cysteine proteinases. Mouse activated T-lymphocytes express cytotoxic T-lymphocyte antigen (CTLA-2), which is homologous to the proregion of mouse cathepsin L. CTLA-2 exhibits inhibitory activities to several cysteine proteinases. We have also identified a similar propeptide-like cysteine proteinase inhibitor, Bombyx cysteine proteinase inhibitor (BCPI), in the silkmoth Bombyx mori. BCPI is a slow and tight binding inhibitor of cathepsin L-like cysteine proteinases with Ki values in picomolar range, and the inhibition is highly selective towards these proteinases just like the propeptides. Recent genome analyses have shown the expression of similar propeptide-like proteins in Drosophila and rat, suggesting the presence of a novel class of cysteine proteinase inhibitors in a variety of organisms. Studies of the gene structures and phylogenetic analysis have shown that genes of the propeptide-like cysteine proteinase inhibitors have emerged from ancestor genes of their parental enzymes.
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Abstract. Reported here is the cloning of the gene for the beta-chain (Ig beta) of the chicken B-cell receptor for antigen. A cDNA library made from B lymphocyte-derived DT40 cells was first screened with a beta-chain cDNA clone from rat. A full-length clone (1556 bp) was obtained encoding a 226-amino-acid beta-chain having 40% sequence identity with the highly conserved beta-chains present in mammals and producing mRNA of 1.7 kb. Clones containing the full B29 gene encoding chicken Ig beta were isolated and fully sequenced. As in mammals, the chicken B29 gene consists of six exons. The chicken B29 gene is somewhat larger (4336 bp) than that of rat (3.1 kb) and human (3.6 kb). Genome collinearity was found in the region of the chicken B29 gene. Genes for potential skeletal muscle sodium channel (2.2 kb upstream) and for growth hormone (2.3 kb downstream) were found in the same order and transcriptional orientation as in mammals, though the genes are more closely positioned in the chicken.
A rare case of chondroblastoma arising from the temporal bone that occurred in a 60-year-old woman is reported. The tumor appeared well demarcated and osteolytic on the radiographs. CT scan clearly depicted marginal and central calcification in the tumor. MR imaging demonstrated two components in the tumor: a solid component with predominantly low signal intensities on both T1- and T2-weighted sequences, and a multilocular cystic component with T1- and T2-elongation and fluid-fluid levels on the T2-weighted images. Postcontrast MR imaging revealed marked enhancement in the solid component and the septa of the cystic component.
The hindgut of Drosophila larvae consists of nine domains that have been distinguished by specific gene expression patterns. In the present study, we examined the ultrastructure of the hindgut of Drosophila larvae, with special reference to the domains, in order to determine whether or not the domains are morphologically distinct functional units. Each domain showed specific ultrastructural features that suggested specific corresponding functions. According to the morphological features, terms are proposed for each domain: the imaginal ring; the "pylorus," which has a thick cuticular layer and well-developed sphincter muscles; the "large intestine," which occupies a major middle portion of the hindgut and has a unique dorsal and ventral subdivision; "border cells," which delineate the anterior and posterior borders of the large intestine and the border between the dorsal and ventral domains of the large intestine; and the "rectum," which is situated at the posterior end of the hindgut and has a thick cuticular layer and sphincter muscles. The morphological features indicate that the large intestine has active absorptive activities. The domains, which have been distinguished by gene expressions, were demonstrated to be functional tissue units of the gut.
The imaging features of primary pericardial mesothelioma have rarely been described. Herein we present a case report of its diagnostic-pathologic features. Chest computed tomography (CT) revealed an irregularly enhanced mass occupying the entire pericardial space and surrounding the superior vena cava. At autopsy, the tumor was found to fill the pericardial space completely, and to extend to the superior vena cava through the superior pericardial sinus. The CT features of the tumor were correlated well with those revealed at autopsy, and provided satisfactory information regarding the presence and the extension of the tumor.
The hindgut of the Drosophila embryo is subdivided into three major domains, the small intestine, large intestine, and rectum, each of which is characterized by specific gene expression. Here we show that the expression of wingless (wg), hedgehog (hh), decapentaplegic (dpp), and engrailed (en) corresponds to the generation or growth of particular domains of the hindgut. wg, expressed in the prospective anal pads, is necessary for activation of hh in the adjacent prospective rectum. hh is expressed in the prospective rectum, which forms anteriorly to the anal pads, and necessary for the expression of dpp at the posterior end of the adjacent large intestine. wg and hh are also necessary for the development of their own expression domains, anal pads, and rectum, respectively. dpp, in turn, causes the growth of the large intestine, promoting DNA replication. en defines the dorsal domain of the large intestine, repressing dpp in this domain. A one-cell-wide domain, which delineates the anterior and posterior borders of the large intestine and its internal border between the dorsal and ventral domains, is induced by the activity of en. We propose a model for the gene regulatory pathways leading to the subdivision of the hindgut into domains.
While left-right (LR) asymmetric morphogenesis is common to various animal species, there have been no systematic studies of the LR asymmetry of body structures of Drosophila melanogaster. In the present paper the LR asymmetric development of the Drosophila gut is described, in which three major parts, the foregut, midgut and hindgut, show almost invariant LR asymmetry. The asymmetry is generated by a twist of each part in particular orientations, resulting in a left-handed (sinistral) convolution as a whole. The frequency of spontaneous reversal of LR orientations is very low (< 0.6%) and reversal of each part of the gut occurs independently. The bicoid mutation causes duplication of the posterior half of the gut, essentially keeping the left-handed twist, suggesting that the LR asymmetry may depend on some intrinsic nature of the cells or tissues rather than a graded distribution of morphogens in the egg. The handedness of particular gut parts was randomized or became symmetric in mutants of brachyenteron, huckebein and patched, suggesting that different gene pathways can interfere in determining LR asymmetry of the gut. It is noteworthy that all of these genes are expressed LR symmetrically.
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OBJECTIVE: To evaluate the efficacy of direct MR arthrography for diagnosing plica synovialis mediopatellaris (PSM). MATERIAL AND METHODS: Twenty-two knees of 19 patients were examined by direct MR arthrography. In 19 of those knees, field-echo T2*-weighted transaxial images were obtained with intra-articular administration of 40 ml of saline ("direct MR arthrography"). In the other 3 knees, T1-weighted transaxial images were obtained with intra-articular administration of 40 ml of gadopentetate dimeglumine. Conventional MR images were evaluated prior to direct MR arthrography in 12 of the 22 knees. The results of direct MR arthrography and conventional MR imaging were compared with the arthroscopic findings. RESULTS: Direct MR arthrography demonstrated 17 of 19 PSMs proved on arthroscopy. The features of 16 PSMs on direct MR arthrography corresponded accurately with the arthroscopic classification. Conventional MR demonstrated only 3 plicae. CONCLUSION: Direct MR arthrography enabled accurate diagnosis of PSMs and could replace diagnostic arthroscopy.
Three new taxane diterpenoids were isolated from the leaves of the Japanese yew, Taxus cuspidta. Their structures were established as 5 alpha,13 alpha-diacetoxy-taxa-4(20),11-diene-9 alpha,10 beta-diol (1), 7 beta,13 alpha-diacetoxy-5 alpha-cinnamyloxy-2(3-->20)-abeo-taxa-4(20),11-diene-2 alpha,10 beta-diol (2), and 2 alpha,10 beta,13 alpha-triacetoxy-taxa-4(20),11-diene-5 alpha,7 beta,9 alpha-triol (3) respectively on the basis of 1D and 2D NMR data.
A new apoptosis inducer, ammocidin, was isolated from the culture broth of Saccharothrix sp. AJ9571. Ammocidin induced apoptotic cell death in Ras-dependent Ba/F3-V12 cells with an IC50 of 66 ng/ml. No cell death was observed in IL-3-dependent Ba/F3-V12 cells at less than 100 microg/ml of ammocidin. Ammocidin significantly reduced the phosphorylation level of MAPK and S6K that mediate the anti-apoptotic function of Ras.
The structure of ammocidin, a new apoptosis inducer in Ras-dependent cells from Saccharothrix sp. AJ9571, was elucidated to be as shown in Fig. 1 by NMR and degradation studies. Ammocidin consists of a 20-membered macrolide ring and three deoxy sugars identified as 6-deoxy-L-glucose, D-digitoxose and D-olivomycose.
PURPOSE: To evaluate the pain relief obtained by radiation therapy for painful bone metastases, with a special regard to general condition. MATERIALS AND METHODS: Between June 1998 and May 2000, 54 patients with 86 painful bone metastases were treated with radiation therapy whose effects could be evaluated for a minimum period of 6 months or until death. Treatment schedules were 3 Gy/fraction/day (30-36 Gy/10-12 fractions) in usual cases (61 lesions), 4-8 Gy/fraction/day (8-20 Gy/1-5 fractions) in patients with a poor general condition (9 lesions), and 2 Gy/fraction/day (40-50 Gy/20-25 fractions) in lesions with a large radiation field (16 lesions). RESULTS: Complete pain relief without medication (CR) was achieved in 40 lesions (47%). Significant predictors for CR were primary site (p = 0.0003), performance status (p = 0.0060), pain score (p = 0.0190), narcotic score (p < 0.0001), and prognosis (p < 0.0001), but no difference was found in CR among treatment schedules. No evidence of severe radiation-induced complication was seen. CONCLUSION: General condition (performance status and prognosis) has an influence on pain relief. Compared with the daily 2 Gy protocol, the daily 3 Gy protocol has the advantage of shorter treatment time. The treatment schedule should be assessed in patients with a large radiation field and/or poor general condition. Especially for the patients with poor general condition, combined pain medication should be considered.