115 research outputs found
Thoracic endovascular aneurysm repair in Japan: Experience with fenestrated stent grafts in the treatment of distal arch aneurysms
ObjectivesIn the West, stent grafts for endovascular repair of thoracic aortic aneurysms have been commercially available for several years, whereas in Japan, a manufactured stent graft was not approved for this application until March 2008. Nevertheless, endovascular thoracic intervention began to be performed in Japan in the early 1990s, with homemade devices used in most cases. Many researchers have continued to develop homemade devices. We have participated in joint design and assessment efforts with a stent graft manufacturer, focusing primarily on fenestrated stent grafts used in repairs at the distal arch, a site especially prone to aneurysm.MethodsFrom 1995 to February 2008, we performed about 1100 endovascular procedures to treat thoracic aortic aneurysms and 682 cases were performed at Tokyo Medical University. In 435 out of 682 the aneurysm was located in the area from the distal arch to the proximal descending aorta. Fenestrated stent grafts were inserted in 288 cases. Computed tomography scans were performed at 3, 6, and 12 months postoperatively and annually thereafter.ResultsThe initial success rate in the entire series was 95.2%. Complications included 26 cerebral infarctions (3.8%), six of which (0.9%) resulted in serious paralysis and changes in consciousness. Among patients who received fenestrated stent grafts, paraplegia occurred in 2.6%, aortic injury in 1.2%, and iliofemoral artery injury in 6.0%. No complications resulted from occlusion of aortic arch branches. At ≥2 years after intervention, aneurysm diameter was reduced in 62% of patients, 33% had no change, and 5% had a diameter enlargement. The stent graft complication rate during follow-up was 8.4%, the device fracture rate was 1.4%, and the device migration rate was 7%. The 5-year survival rate was 62.4%, with follow-up in 96.8% of the patients.ConclusionEndovascular repair has promising results in the descending thoracic aortic region, although some stent grafts and their delivery systems can still be improved. Additional commercial developments and available stent grafts designed for use in the distal arch are urgently needed
The Insulin receptor catalyzes the tyrosine phosphorylation o Caveolin 1
Our previous studies revealed that insulin stimulates the tyrosine phosphorylation of caveolin in 3T3L1 adipocytes. To explore the mechanisms involved in this event, we evaluated the association of the insulin receptor with caveolin. The receptor was detected in a Triton-insoluble low density fraction, co-sedimenting with caveolin and flotillin on sucrose density gradients. We also detected the receptor in caveolin-enriched rosette structures by immunohistochemical analysis of plasma membrane sheets from 3T3L1 adipocytes. Insulin stimulated the phosphorylation of caveolin-1 on Tyr14. This effect of the hormone was not blocked by overexpression of mutant forms of the Cbl-associated protein that block the translocation of phospho-Cbl to the caveolin-enriched, lipid raft microdomains. Moreover, this phosphorylation event was also unaffected by inhibitors of the MAPK and phosphatidylinositol 3-kinase pathways. Although previous studies demonstrated that the Src family kinase Fyn was highly enriched in caveolae, an inhibitor of this kinase had no effect on insulin-stimulated caveolin phosphorylation. Interestingly, overexpression of a mutant form of caveolin that failed to interact with the insulin receptor did not undergo phosphorylation. Taken together, these data indicate that the insulin receptor directly catalyzes the tyrosine phosphorylation of caveolin. Previous article in issu
Development of a mesoscopic framework spanning nanoscale protofibril dynamics to macro-scale fibrin clot formation
Thrombi form a micro-scale fibrin network consisting of an interlinked structure of nanoscale protofibrils, resulting in haemostasis. It is theorized that the mechanical effect of the fibrin clot is caused by the polymeric protofibrils between crosslinks, or to their dynamics on a nanoscale order. Despite a number of studies, however, it is still unknown, how the nanoscale protofibril dynamics affect the formation of the macro-scale fibrin clot and thus its mechanical properties. A mesoscopic framework would be useful to tackle this multi-scale problem, but it has not yet been established. We thus propose a minimal mesoscopic model for protofibrils based on Brownian dynamics, and performed numerical simulations of protofibril aggregation. We also performed stretch tests of polymeric protofibrils to quantify the elasticity of fibrin clots. Our model results successfully captured the conformational properties of aggregated protofibrils, e.g., strain-hardening response. Furthermore, the results suggest that the bending stiffness of individual protofibrils increases to resist extension.Takeishi Naoki, Shigematsu Taiki, Enosaki Ryogo, Ishida Shunichi, Ii Satoshi and Wada Shigeo 2021Development of a mesoscopic framework spanning nanoscale protofibril dynamics to macro-scale fibrin clot formationJ. R. Soc. Interface.182021055420210554 http://doi.org/10.1098/rsif.2021.055
Lipid raft microdomain compartalization of TC10 is required for insulin signalling and Glut4 Translocation
Recent studies indicate that insulin stimulation of glucose transporter (GLUT)4 translocation requires at least two distinct insulin receptor-mediated signals: one leading to the activation of phosphatidylinositol 3 (PI-3) kinase and the other to the activation of the small GTP binding protein TC10. We now demonstrate that TC10 is processed through the secretory membrane trafficking system and localizes to caveolin-enriched lipid raft microdomains. Although insulin activated the wild-type TC10 protein and a TC10/H-Ras chimera that were targeted to lipid raft microdomains, it was unable to activate a TC10/K-Ras chimera that was directed to the nonlipid raft domains. Similarly, only the lipid raft-localized TC10/ H-Ras chimera inhibited GLUT4 translocation, whereas the TC10/K-Ras chimera showed no significant inhibitory activity. Furthermore, disruption of lipid raft microdomains by expression of a dominant-interfering caveolin 3 mutant (Cav3/DGV) inhibited the insulin stimulation of GLUT4 translocation and TC10 lipid raft localization and activation without affecting PI-3 kinase signaling. These data demonstrate that the insulin stimulation of GLUT4 translocation in adipocytes requires the spatial separation and distinct compartmentalization of the PI-3 kinase and TC10 signaling pathways
Long-term result of hybrid procedure for an extensive thoracic aortic aneurysm in Takayasu arteritis: a case report
We herein present a 60 years old woman with Takayasu arteritis and an extensive thoracic aortic aneurysm who initially underwent a total aortic arch replacement. Then, in the second stage, thoracic endovascular aortic repair was performed using the elephant trunk graft as the proximal landing zone at four weeks after aortic arch repair. The postoperative course was relatively uncomplicated, but a type II endoleak was noted. Currently, about 5 years postoperatively, the slight type II endoleak from intercostal artery persists, but aneurism dilatation has not been noted, so the patient is being followed up
Structural Insights Into RNA Bridging Between HIV-1 Vif and Antiviral Factor APOBEC3G
Great effort has been devoted to discovering the basis of A3G-Vif interaction, the key event of HIV\u27s counteraction mechanism to evade antiviral innate immune response. Here we show reconstitution of the A3G-Vif complex and subsequent A3G ubiquitination in vitro and report the cryo-EM structure of the A3G-Vif complex at 2.8 Å resolution using solubility-enhanced variants of A3G and Vif. We present an atomic model of the A3G-Vif interface, which assembles via known amino acid determinants. This assembly is not achieved by protein-protein interaction alone, but also involves RNA. The cryo-EM structure and in vitro ubiquitination assays identify an adenine/guanine base preference for the interaction and a unique Vif-ribose contact. This establishes the biological significance of an RNA ligand. Further assessment of interactions between A3G, Vif, and RNA ligands show that the A3G-Vif assembly and subsequent ubiquitination can be controlled by amino acid mutations at the interface or by polynucleotide modification, suggesting that a specific chemical moiety would be a promising pharmacophore to inhibit the A3G-Vif interaction
Adolescent Scoliosis Screening in Nara City Schools: A 23-Year Retrospective Cross-Sectional Study
Study DesignRetrospective cross-sectional study.PurposeTo determine the prevalence of idiopathic scoliosis, define the distribution of the curve magnitude, evaluate the accuracy of Moiré topography as a screening tool, and investigate the cost-effectiveness of our screening system.Overview of LiteratureEarly detection of idiopathic scoliosis provides the opportunity for conservative treatment before the deformity is noticeable. We believe that scoliosis screening in schools is useful for detection; however, screening programs are controversial owing to over referral of students who do not require further testing or follow-up. In Japan, school scoliosis screening programs are mandated by law with individual policies determined by local educational committees. We selected Moiré topography as the scoliosis screening tool for schools in Nara City.MethodsWe selected Moiré topography as the scoliosis screening tool for schools in Nara City. We screened boys and girls aged 11-14 years and reviewed the school scoliosis screening results from 1990 to 2012.ResultsA total of 195,149 children aged 11-14 years were screened. The prevalence of scoliosis (defined as ≥10° curvature) was 0.057%, 0.010%, and 0.059% in fifth, sixth, and seventh grade boys and 0.337%, 0.369%, and 0.727% in fifth, sixth, and seventh grade girls, respectively. The false-positive rate of our Moiré topography was 66.7%. The minimum cost incurred for scoliosis detection in one student was 2,000 USD.ConclusionsThe overall prevalence of scoliosis was low in the students of Nara City schools. Over 23 years, the prevalence of scoliosis in girls increased compared to that in the first decade of the study
In vitro transcription of compound heterozygous hypofibrinogenemia Matsumoto IX; first identification of FGB IVS6 deletion of 4 nucleotides and FGG IVS3-2A > G causing abnormal RNA splicing
BackgroundWe reported a case of hypofibrinogenemia Matsumoto IX (M IX) caused by a novel compound heterozygous mutation involving an FGB IVS6 deletion of 4 nucleotides (Δ4b) (three T, one G; between FGB IVS6-10 and -16) and FGG IVS3-2A/G, which are both identified for the first time. To examine the transcription of mRNA from the M IX gene, we cloned the wild-type and mutant genes into expression vectors.MethodsThe vectors were transfected into CHO cells and transiently produced wild-type, Bβ- or γ-mRNA in the cells. The mRNAs amplified with RT-PCR were analyzed by agarose gel electrophoresis and nucleotide sequencing.ResultsThe RT-PCR product from FGB IVS6Δ4b showed aberrant mRNA that included both introns 6 and 7, and that from FGG IVS3-2G showed two aberrant mRNAs, a major one including intron 3 and a minor in which intron 3 was spliced by a cryptic splice site in exon 4. We speculated that the aberrant mRNAs are degraded before translation into proteins, and/or translated variant chains are subjected to quality control and degraded in the cytoplasm.ConclusionThe reduced plasma fibrinogen level of the M IX patient was caused by abnormal RNA splicing of one or both of the FGB and FGG genes
Geographical Contents in Primary School : An Analysis of the English Geography Textbook “Collins Primary Geography”
In this study, we have analyzed the English geography textbook “Collins Primary Geography”, in order to clarify the characteristics of geographical contents in primary school. Results of this study are as follows: age (grade)-appropriate teaching through different process of leaning (awareness, understanding, cognition and value judgement) and physical, human, environmental geography and topography as a content. However, there are no contents across physical and human geography, one of the features of geography, in the textbook.本稿は,2016年度前期開講の地理認識内容学特講(由井担当)の一部をもとに,加筆・修正を加えたものである
Incidence of seed migration to the chest, abdomen, and pelvis after transperineal interstitial prostate brachytherapy with loose 125I seeds
<p>Abstract</p> <p>Background</p> <p>The aim was to determine the incidence of seed migration not only to the chest, but also to the abdomen and pelvis after transperineal interstitial prostate brachytherapy with loose <sup>125</sup>I seeds.</p> <p>Methods</p> <p>We reviewed the records of 267 patients who underwent prostate brachytherapy with loose <sup>125</sup>I seeds. After seed implantation, orthogonal chest radiographs, an abdominal radiograph, and a pelvic radiograph were undertaken routinely to document the occurrence and sites of seed migration. The incidence of seed migration to the chest, abdomen, and pelvis was calculated. All patients who had seed migration to the abdomen and pelvis subsequently underwent a computed tomography scan to identify the exact location of the migrated seeds. Postimplant dosimetric analysis was undertaken, and dosimetric results were compared between patients with and without seed migration.</p> <p>Results</p> <p>A total of 19,236 seeds were implanted in 267 patients. Overall, 91 of 19,236 (0.47%) seeds migrated in 66 of 267 (24.7%) patients. Sixty-nine (0.36%) seeds migrated to the chest in 54 (20.2%) patients. Seven (0.036%) seeds migrated to the abdomen in six (2.2%) patients. Fifteen (0.078%) seeds migrated to the pelvis in 15 (5.6%) patients. Seed migration occurred predominantly within two weeks after seed implantation. None of the 66 patients had symptoms related to the migrated seeds. Postimplant prostate D90 was not significantly different between patients with and without seed migration.</p> <p>Conclusion</p> <p>We showed the incidence of seed migration to the chest, abdomen and pelvis. Seed migration did not have a significant effect on postimplant prostate D90.</p
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