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BACKGROUND AND AIM: Endoscopic ultrasound-guided gastroenterostomy is a procedure used to connect the stomach and dilated afferent loop using a stent under endoscopic ultrasound for afferent loop syndrome. However, the actual efficacy and safety of this procedure remain unclear. Therefore, this retrospective study aimed to evaluate the efficacy and safety of endoscopic ultrasound-guided gastroenterostomy using a laser-cut-type fully covered self-expandable metallic stent and an anchoring plastic stent for afferent loop syndrome. METHODS: Technical and clinical success rates, adverse events, recurrent intestinal obstruction rates, time to recurrent intestinal obstruction, and technical and clinical success rates of re-intervention were evaluated in intended patients who underwent endoscopic ultrasound-guided gastroenterostomy for afferent loop syndrome from October 2018 to August 2022. RESULTS: In 25 intended patients with afferent loop syndrome who intended endoscopic ultrasound-guided gastroenterostomy, the technical success rate was 100% (25/25), whereas the clinical success rate was 96% (24/25). Two patients experienced grade ≥ 3 early adverse events, including one with intra-abdominal abscess and one with hypotension. Both events were attributed to intestinal fluid leakage. No late adverse events were observed. The recurrent intestinal obstruction rate was 32% (8/25), and the median time to recurrent intestinal obstruction was 6.5 months (95% confidence interval: 2.8-not available). The technical and clinical success rates of re-intervention were both 100% (8/8). CONCLUSIONS: Endoscopic ultrasound-guided gastroenterostomy using a fully covered self-expandable metallic stent and an anchoring plastic stent is effective and safe as a treatment procedure for afferent loop syndrome.
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OBJECTIVES: Immune-related adverse event-sclerosing cholangitis caused by treatment with immune checkpoint inhibitors is rare, and the diagnostic criteria and treatment strategy remain unclear. In this study, we confirmed the clinicopathological features of immune-related adverse event-sclerosing cholangitis and clarified its diagnosis and appropriate management. METHODS: We retrospectively evaluated 10 patients diagnosed with immune-related adverse event-sclerosing cholangitis and identified by electronic database searches. RESULTS: Blood tests revealed liver dysfunction with a predominance of biliary tract enzymes in all patients; however, jaundice was present in only one patient. Contrast-enhanced computed tomography revealed diffuse hypertrophy of the extrahepatic bile duct wall as the most frequent finding; however, endoscopic retrograde cholangiopancreatography showed various imaging features, such as the pruned-tree appearance of intrahepatic bile ducts, in all patients. Transpapillary bile duct biopsy showed inflammatory cell infiltration using immunostaining, with a predominance of cluster of differentiation 8-positive T cells in 63% of the cases. Initial steroid therapy was effective in two cases. Mycophenolate mofetil and tacrolimus were used in steroid-refractory cases. Although six patients showed improvements, all of the remaining patients died owing to immune-related adverse event-sclerosing cholangitis. CONCLUSIONS: Various bile duct imaging findings of immune-related adverse event-sclerosing cholangitis were revealed; transpapillary bile duct biopsy may be useful in the diagnosis of immune-related adverse event-sclerosing cholangitis. Despite the combination of multiple immunosuppressive agents, prognosis of immune-related adverse event-sclerosing cholangitis remains poor. Longer follow-up and larger clinical studies are necessary to establish its treatment strategy.
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Colangitis Esclerosante , Inhibidores de Puntos de Control Inmunológico , Humanos , Colangitis Esclerosante/inducido químicamente , Colangitis Esclerosante/diagnóstico por imagen , Colangitis Esclerosante/patología , Colangitis Esclerosante/inmunología , Colangitis Esclerosante/tratamiento farmacológico , Masculino , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Tomografía Computarizada por Rayos X , Adulto , Anciano de 80 o más AñosRESUMEN
OBJECTIVES: There is a lack of quantitative and objective methods for measuring skin hardness. This study aimed to verify whether SOFTGRAM, a device that can measure elastic modulus using the Hertz elastic contact theory, could be used to evaluate skin hardness in systemic sclerosis (SSc). METHODS: Skin score according to the modified Rodnan total skin thickness score and elastic modulus of the skin using SOFTGRAM were measured for 20 patients with SSc and 20 healthy controls on 8 parts of the body, both of the cheeks, forearms, fingers, and hands. Five observers shared to measure skin score 320 times (40 participants × 8 parts). Elastic modulus was measured 1600 times (40 participants × 8 parts × 5 times each). As an additional examination to compare differences between observers, the skin score of another healthy control was measured 40 times (5 observers × 8 parts). Elastic modulus was measured 200 times (5 observers × 8 parts × 5 times each). RESULTS: There was a significant correlation between elastic modulus and skin score (correlation coefficient=0.67, p<0.001) and a significant difference in elastic modulus (8 parts: healthy controls vs. limited cutaneous SSc vs. diffuse cutaneous SSc: 22.6±15.7 vs. 32.0±27.7 vs. 44.8±39.8, p<0.001). Intraobserver reliabilities were sufficient in 6 out of 7 observers; however, interobserver was less satisfactory. CONCLUSIONS: This study showed the practicality of SOFTGRAM as an accurate measurement method of skin hardness but also revealed points to be improved. More studies are needed to find an accurate measurement method of skin hardness.
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OBJECTIVES: Comprehensive genomic profiling (CGP) has been approved in Japan since June 2019, enabling mutation-specific therapy. Although tissue sampling via endoscopic ultrasound-guided tissue acquisition (EUS-TA) is standard in pancreatic cancer, reports on obtaining appropriate samples for CGP, especially for the OncoGuide NCC Oncopanel System (NOP) and FoundationOne CDx (FOne), are lacking. Therefore, we investigated the success rate and factors related to appropriate EUS-TA sampling for CGP analysis suitability in unresectable pancreatic ductal adenocarcinoma (UR-PDAC). METHODS: Participants comprised 150 UR-PDAC patients who underwent EUS-TA and tumor sample evaluation for CGP analysis suitability between June 2019 and December 2021. The proportion of patients meeting the criteria was evaluated considering tumor size, puncture lesion, presence of metastasis, type and size of puncture needle, suction method, number of punctures, and puncture route. RESULTS: In total, 39.2% (60/153) of samples met NOP analysis suitability criteria and 0% met FOne analysis suitability criteria. The suitability rate was significantly higher with 19G fine-needle biopsy (FNB) (56.0%; 42/75) than with 22G FNB (32.6%; 14/43) and 22G fine-needle aspiration (11.4%; 4/35). Nineteen-gauge needle (odds ratio [OR] 2.53; 95% confidence interval [CI] 1.15-5.57; P = 0.021) and FNB (OR 3.57; 95% CI 1.05-12.20; P = 0.041) were independent factors contributing to NOP analysis suitability. Among 30 patients who underwent actual NOP analysis, the analysis success rate was 100% (30/30). CONCLUSION: In sample collection via EUS-TA, 19G and FNB needles contribute to NOP analysis suitability.
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Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Páncreas/diagnóstico por imagen , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/métodos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Adenocarcinoma/patología , Genómica , Neoplasias PancreáticasAsunto(s)
Endosonografía , Stents , Humanos , Endosonografía/métodos , Ultrasonografía Intervencional , Punciones/métodos , Masculino , FemeninoRESUMEN
We examined the effects of predator-prey distance (PPD) and trajectory of the predator on the body patterns that the pharaoh cuttlefish, Sepia pharaonis, shows in response to a predator. A model predator moving in three different trajectories was presented to the cuttlefish: T1, approached the cuttlefish but bypassed above; T2, approached directly toward the cuttlefish; T3, bypassed the cuttlefish both vertically and horizontally. We divided the body patterns that the cuttlefish expressed into seven categories, i.e., "uniform light", "disruptive", "center circle", "dark square", "vertical stripe", "all dark" and "eyespots". In T1, the number of individuals that showed "dark square" increased as the model approached the cuttlefish, whereas the number of individuals that showed "disruptive" decreased. In T2, the number of individuals that showed "all dark" and "eyespots" increased as the model approached the cuttlefish. In T3, the number of individuals that showed "dark square" and "vertical stripe" increased as the model approached the cuttlefish, and it tended to decrease as the model receded from the cuttlefish. These results demonstrate that S. pharaonis changes its body patterns according to PPD and the trajectory of the predator, which would affect predation risk and/or predator perception.
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Conducta Animal/fisiología , Reacción de Fuga/fisiología , Sepia/fisiología , Percepción Visual , Animales , Sensibilidad de Contraste , PecesRESUMEN
Background and study aims Endoscopic ultrasound-guided pancreatic duct drainage (EUS-PD) is emerging as an effective alternative treatment for obstructive pancreatitis after unsuccessful endoscopic retrograde pancreatography (ERP). However, the high incidence of adverse events associated with EUS-PD (approximately 20%) remains an issue. Recently, we developed a novel plastic stent for EUS-PD, with a radiopaque marker positioned at approximately one-third of the length from the distal end of the stent and side holes positioned exclusively distal to the marker. This study aimed to evaluate the feasibility and safety of using this stent in EUS-PD. Patients and methods We retrospectively reviewed data from 10 patients who underwent EUS-PD with the novel plastic stent at the National Cancer Center Hospital between March 2021 and October 2023. Technical and clinical success, procedure times, adverse events (AEs), recurrent pancreatic duct obstruction (RPO), and time to RPO were assessed. Results Of the 10 patients, five had postoperative benign pancreaticojejunal anastomotic strictures and five had malignant pancreatic duct obstruction. The technical and clinical success rates were both 100% (10/10). An AE (self-limited abdominal pain) occurred in one patient (10.0%). Two patients (20.0%) died of their primary disease during the follow-up period (median, 44 days; range, 25-272 days). The incidence of RPO was 10.0% (1/10), and the 3-month non-RPO rate was 83.3%. Conclusions The novel plastic stent shows potential as a useful and safe tool in EUS-PD.
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Background and study aims Endoscopic gastroduodenal stent (GDS) deployment is currently a standard treatment for malignant gastric outlet obstruction (mGOO) in patients with limited life expectancy; however, stent dysfunction (SD) and complicated pancreatitis often occur after GDS deployment. We investigated incidence and contributing factors of SD and complicated pancreatitis. Patients and methods We retrospectively reviewed 203 patients who underwent initial GDS deployment for palliation of mGOO symptoms between October 2017 and July 2022, including 109 who underwent GDS deployment across the duodenal papilla (sub-cohort). Results SDs, including tumor ingrowth (n = 26), kinking (n = 14), and migration (n = 13), occurred in 68 patients (33.5%). Cumulative SD incidence was 41.1% (95% confidence interval, 32.6-49.4%). SD incidence increased to 0.4%, 0.16%, and 0.06% per day at < 8, 8-16, and>16 weeks, respectively. On multivariate analysis, Niti-S pyloric/duodenal stent deployment (sub-distribution hazard ratio [sHR] 0.26, P = 0.01) and survival length ≥ 90 days (sHR 2.5, P = 0.01) were respectively identified as favorable and risk factors significantly associated with SD. Pancreatitis developed in 14 patients (12.8%) in the sub-cohort, which had significantly higher parenchymal diameter ( P < 0.01) and lower main pancreatic duct (MPD) caliber ( P < 0.01) than the non-pancreatitis cohort. On multivariate analysis, MPD caliber < 3 mm independently predicted pancreatitis (odds ratio 6.8, P = 0.03). Conclusions Deployment of the Niti-S pyloric/duodenal stent, with conformability even for angulated strictures, significantly reduced the incidence of SD. Stent selection, life expectancy, and MPD caliber should be taken into consideration during decision-making for GDS deployment for mGOO.
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Background and study aims Endoscopic ultrasound-guided hepaticogastrostomy with bridging between the left and right bile ducts is an alternative to endoscopic transpapillary drainage for malignant hilar biliary obstruction. We aimed to analyze the long-term stent patency of endoscopic ultrasound-guided hepaticogastrostomy with bridging. Patients and methods Patients who underwent endoscopic ultrasound-guided hepaticogastrostomy with bridging between April 2018 and July 2023 were retrospectively analyzed. We retrospectively compared the stent patency of these patients with that of the individuals who underwent endoscopic transpapillary drainage-multi-stenting using unmatched (entire) and propensity score-matched cohorts. Results Endoscopic ultrasound-guided hepaticogastrostomy with bridging had a technical success rate of 90% (18/20). Adverse events were minimal. The number of clinical success cases was 17 and 82 for endoscopic ultrasound-guided hepaticogastrostomy with bridging using metallic stent and endoscopic transpapillary drainage-multi-stenting, respectively. The recurrent biliary obstruction rate was 17.6% and 58.5% for endoscopic ultrasound-guided hepaticogastrostomy with bridging and endoscopic transpapillary drainage-multi-stenting, respectively; the median time to recurrent biliary obstruction (days) was significantly longer for endoscopic ultrasound-guided hepaticogastrostomy with bridging in the entire (not reached vs. 104, P =0.03) and propensity score-matched (183 vs. 79, P =0.05) cohorts. The non-recurrent biliary obstruction rate for endoscopic ultrasound-guided hepaticogastrostomy with bridging was 91.6% at 3 and 6 months and 57% at 12 months. Multivariate analyses revealed that endoscopic ultrasound-guided hepaticogastrostomy with bridging contributed to a lower recurrent biliary obstruction incidence (hazard ratio, 0.31, P =0.05) without significant difference. Conclusions Stent patency was significantly better for endoscopic ultrasound-guided hepaticogastrostomy with bridging. However, future prospective studies are needed.
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Background and Objectives: EUS tissue acquisition (EUS-TA) is the standard diagnostic method for solid pancreatic lesions (SPLs); however, there are few reports on EUS-TA results for SPLs ≤10 mm. Furthermore, given the recent advent of fine-needle biopsy, the current diagnostic accuracy of EUS-TA for SPLs ≤10 mm is unknown. This study aimed to evaluate the diagnostic accuracy and efficacy of EUS-TA for SPLs ≤10 mm. Methods: We retrospectively analyzed the data of 109 patients with SPLs ≤10 mm who underwent EUS-TA. All patients underwent rapid on-site specimen evaluation. Results: The median tumor diameter was 8 mm (range, 2.5-10 mm), and the technical success rate was 99.1% (108/109). Adverse events were observed in 3 patients (2.8%). The diagnostic performance was as follows: sensitivity, 90.1% (64/71); specificity, 97.3% (36/37); accuracy, 92.6% (100/108); positive predictive value, 98.5% (64/65); and negative predictive value, 83.7% (36/43). Multivariate analysis revealed that the number of punctures (odds ratio, 7.03; 95% confidence interval, 1.32-37.5; P = 0.023) and tumor type (odds ratio, 11.90; 95% confidence interval, 1.38-102.0; P = 0.024) were independent risk factors for inaccurate EUS-TA results. The diagnostic accuracy of EUS-TA for pancreatic ductal adenocarcinoma was 87.5% (14/16). No EUS-TA-related needle-tract seeding was observed in patients with pancreatic ductal adenocarcinoma during the observation period. Conclusions: EUS-TA for SPLs ≤10 mm showed adequate diagnostic accuracy and was safe for use with rapid on-site specimen evaluation in all cases.
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An alkoxysilane with an alkyl chain is introduced as an alignment-controlling agent of a block-copolymer-templated mesostructured silica film. Use of the alkylalkoxysilane achieves the alignment of the mesochannels of a triblock-copolymer-templated film by an intermolecular interaction with a rubbing-treated polyimide film. Co-use of an alkoxysilane with a hydroxymethyl group as a hydrophobicity reducing agent improves the alignment close to that of the film prepared using an alkyl surfactant. This concept widens the range of the structural period of aligned mesoporous films and thus widens the useful range of the anisotropic optical properties.
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Background: Whether fibroblast growth factor 23 (FGF23) directly induces left ventricular hypertrophy (LVH) remains controversial. Recent studies showed an association between FGF23 and the renin-angiotensin-aldosterone system (RAAS). The aim of this study was to investigate changes in FGF23 levels and RAAS parameters and their influences on LVH. Methods: In the first experiment, male C57BL/6J mice were divided into sham and transverse aortic constriction (TAC) groups. The TAC group underwent TAC at 8 weeks of age. At 1, 2, 3, and 4 weeks after TAC, the mice were sacrificed, and blood and urine samples were obtained. Cardiac expressions of FGF23 and RAAS-related factors were evaluated, and cardiac histological analyses were performed. In the second experiment, the sham and TAC groups were treated with vehicle, angiotensin-converting enzyme (ACE) inhibitor, or FGF receptor 4 (FGFR4) inhibitor and then evaluated in the same way as in the first experiment. Results: In the early stage of LVH without chronic kidney disease, serum FGF23 levels did not change but cardiac FGF23 expression significantly increased along with LVH progression. Moreover, serum aldosterone and cardiac ACE levels were significantly elevated, and cardiac ACE2 levels were significantly decreased. ACE inhibitor did not change serum FGF23 levels but significantly decreased cardiac FGF23 levels with improvements in LVH and RAAS-related factors, while FGFR4 inhibitor did not change the values. Conclusions: Not serum FGF23 but cardiac FGF23 levels and RAAS parameters significantly changed in the early stage of LVH without chronic kidney disease. RAAS blockade might be more crucial than FGF23 blockade for preventing LVH progression in this condition.
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Hipertrofia Ventricular Izquierda , Insuficiencia Renal Crónica , Animales , Masculino , Ratones , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/metabolismo , Hipertrofia Ventricular Izquierda/patología , Ratones Endogámicos C57BL , Miocitos Cardíacos/metabolismo , Insuficiencia Renal Crónica/patología , Sistema Renina-AngiotensinaRESUMEN
Attempts at performing endoscopic ultrasound-guided tissue acquisition (EUS-TA) with a 19G needle are increasing because histological diagnosis and comprehensive genomic profiling are a necessity. However, the diagnostic ability of the 19G fine-needle biopsy (FNB) needle, especially the third-generation FNB needle, is unclear and has been retrospectively reviewed. The 19G TopGain needle was used in 147 patients and 160 lesions between September 2020 and December 2021. The technical success rate of the biopsies was 99.4% (159/160). The early adverse event rate was 4.1% (6/147), and moderate or severe adverse event rate occurrence was 2.0% (3/147). The sensitivity, specificity, and accuracy of the 19G TopGain needle for 157 lesions with a confirmed diagnosis were 96.7%, 100%, and 96.8%, respectively. Rescue EUS-TA using the 19G TopGain needle was performed for nine lesions, and a successful diagnosis was made in six of these lesions (66.7%). The diagnostic ability of EUS-TA using the third-generation 19G TopGain needle was favorable. However, the use of 19G FNB needles may increase adverse events. Therefore, EUS-TA with a 19G FNB needle is mainly indicated in lesions where comprehensive genomic profiling may be necessary or the diagnosis could not be determined via EUS-TA using the 22G needle.
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INTRODUCTION: The current endoscopic treatment for postoperative benign hepaticojejunostomy anastomotic stricture (HJAS) has a high technical success rate and is highly effective in the short term. However, long-term results have shown a high rate of stenosis recurrence, which indicates an insufficient response to treatment. Three prospective studies on fully covered self-expandable metallic stent (FC-SEMS) treatment for benign HJAS used the stenosis resolution rate as the primary endpoint, and no study has yet used the long-term non-stenosis rate (at 12 months) as the primary endpoint. METHODS AND ANALYSIS: We launched the 'saddle-cross study', which will be conducted as a multicentre, prospective intervention of endoscopic treatment using two modified FC-SEMSs (BONASTENTï¸ M-Intraductal) that have been improved for benign stenosis in patients with benign HJAS, with the long-term non-restenosis rate (at 12 months) as the primary endpoint. This study aims to evaluate the long-term non-restenosis rate (at 12 months) and safety of the saddle-cross technique for benign HJAS. We plan to enrol 50 participants. ETHICS AND DISSEMINATION: This study has been approved by the Certified Review Board of the National Cancer Center, Japan (CRB3180009). The results will be reported at various conferences and published in international peer-reviewed journals.
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Stents Metálicos Autoexpandibles , Humanos , Constricción Patológica/etiología , Constricción Patológica/cirugía , Estudios Prospectivos , Resultado del Tratamiento , Estudios Retrospectivos , Stents Metálicos Autoexpandibles/efectos adversos , Stents , Ensayos Clínicos Fase II como Asunto , Estudios Multicéntricos como AsuntoRESUMEN
BACKGROUND: For non-functioning pancreatic neuroendocrine tumors (pNETs) ≤ 20 mm, most guidelines consider follow-up observations as an option; however, the various treatment strategies are defined by size alone, even though the Ki-67 index is important for malignancy grading. Endoscopic ultrasound-guided tissue acquisition (EUS-TA) is the standard for the histopathological diagnosis of solid pancreatic lesions; however, recent results for small lesions remain unclear. Therefore, we examined the efficacy of EUS-TA for solid pancreatic lesions ≤ 20 mm suspected as pNETs or requiring differentiation and the non-increase rate in tumor size in follow-up cases. METHODS: We retrospectively analyzed data of 111 patients (median age = 58 years) with lesions ≤ 20 mm suspected as pNETs or requiring differentiation who underwent EUS-TA. All patients underwent specimen evaluation by rapid onsite evaluation (ROSE). RESULTS: EUS-TA led to a diagnosis of pNETs in 77 patients (69.4%) and tumors other than pNETs in 22 patients (19.8%). The histopathological diagnostic accuracy of EUS-TA was 89.2% (99/111) overall, 94.3% (50/53) for 10-20 mm lesions, and 84.5% (49/58) for ≤ 10 mm lesions, with no significant difference in diagnostic accuracy (p = 0.13). The Ki-67 index was measurable in all patients with a histopathological diagnosis of pNETs. Among 49 patients with a diagnosis of pNETs who were followed up, one patient (2.0%) showed tumor enlargement. CONCLUSIONS: EUS-TA for solid pancreatic lesions ≤ 20 mm suspected as pNETs or requiring differentiation is safe and has adequate histopathological diagnostic accuracy, suggesting that follow-up observations of pNETs with a histological pathologic diagnosis are acceptable in the short term.
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Tumores Neuroectodérmicos Primitivos , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Humanos , Persona de Mediana Edad , Tumores Neuroendocrinos/diagnóstico por imagen , Tumores Neuroendocrinos/patología , Estudios Retrospectivos , Antígeno Ki-67 , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/patologíaRESUMEN
Background and study aims Recently, the utility of endoscopic ultrasound-guided intervention without fistula dilation (EUS-IV WoD) has been reported to prevent adverse events. We clinically evaluated cases in which EUS-IV WoD was attempted using a novel self-expandable metallic stent (SEMS); this is a fully covered, laser-cut SEMS that has a tapered and stiff tip specifically designed for a 0.025-inch guidewire and a relatively thin, 7F delivery system. Patients and methods We retrospectively evaluated cases wherein EUS-IV WoD was attempted using the novel SEMS between March and December 2021. Results Treatment of 11 patients by EUS-IV WoD with the novel SEMS was attempted. The technical success rate for EUS-IV was 100â% and the clinical success rate was 100â%; the success rate for EUS-IV WoD was 72.8â%. Of these, the procedural success rate for EUS-IV WoD was 100â% in EUS-biliary drainage (BD) and 57.1â% in non-EUS-BD. Early adverse events were observed in 27.3â% of patients (3/11): mild abdominal pain in two patients and moderate bleeding in one patient. The abdominal pain cases were both cases of EUS-IV WoD failure and required fistula dilation. Conclusions The novel stent may be useful for EUS-IV WoD, especially in EUS-BD.
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Exceptionally strong Bragg diffraction from a mesoporous silica film is achieved by exposing the as-deposited film to vapor of chlorotrimethylsilane (Me(3)SiCl) before extracting the surfactant. The intensity of the X-ray diffraction peak increased 7 times after the surfactant removal and it approached 30% reflectivity. This large increase of diffraction intensity cannot be explained simply by the improved contrast of the electron density, and rearrangement of the pore wall during the Me(3)SiCl vapor treatment is suggested. It is shown by infrared spectroscopy that Me(3)SiCl with a high grafting reactivity effectively caps the silanol groups and prevents the following condensation, which causes the structural degradation. The substitution of the hydrogen atom of hydroxyl groups with trimethylsilyl groups should help the improvement of the structural regularity by reducing the hydrogen bonds in the pore wall. The achieved strong diffraction opens the gate for the application of these regular mesoporous films prepared by a self-assembly process to optical elements in the X-ray region.
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Chitosan is a cationic polymer that forms polymerized membranes upon reaction with anionic polymers. Chitosan-carboxymethyl cellulose (CMC) capsules are drug delivery carrier candidates whose mechanical strength and permeability must be controlled to achieve sustained release. In this study, the capsules were prepared from chitosan-γ-glycidoxypropyltrimethoxysilane (GPTMS)-CMC. The mechanical stability of the capsules was improved by crosslinking the chitosan with GPTMS. The capsules were then coated with hydroxyapatite (HAp) by alternately soaking them in calcium chloride solution and disodium hydrogen phosphate solution to prevent rapid initial drug release. Cytochrome C (CC), as a model drug, was introduced into the capsules via two routes, impregnation and injection, and then the CC released from the capsules was examined. HAp was found to be deposited on the internal and external surfaces of the capsules. The amount of CC introduced, and the release rate were reduced by the HAp coating. The injection method was found to result in the greatest CC loading.
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Serum fibroblast growth factor 23 (FGF23) levels and the renin-angiotensin-aldosterone system (RAAS) are elevated in chronic kidney disease (CKD) patients, and their association with left ventricular hypertrophy (LVH) has been reported. However, whether the FGF23 elevation is the cause or result of LVH remains unclear. At 10 weeks, male C57BL/6J mice were divided into 4 groups: sham, CKD (5/6 nephrectomy), LVH (transaortic constriction), and CKD/LVH group. At 16 weeks, the mice were euthanized, and blood and urine, cardiac expressions of FGF23 and RAAS-related factors, and cardiac histological analyses were performed. Heart weight, serum FGF23 levels, and cardiac expression of FGF23 and RAAS-related factors, except for angiotensin-converting enzyme 2, were more increased in the CKD/LVH group compared to the other groups. A significant correlation between LVH and cardiac expressions of FGF23 and RAAS-related factors was observed. Furthermore, there was a significantly close correlation of the cardiac expression of FGF23 with LVH and RAAS-related factors. The coexisting CKD and LVH increased serum and cardiac FGF23 and RAAS-related factors, and there was a significant correlation between them. A close correlation of cardiac, but not serum FGF23, with LVH and RAAS suggests that local FGF23 levels may be associated with LVH and RAAS activation.
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Mesoporous titania-silica composite films with highly aligned cylindrical pores are prepared by the sol-gel method using a substrate with structural anisotropy. The strong alignment effect of a rubbing-treated polyimide film on a substrate provides a narrow alignment distribution in the plane of the film regardless of the fast condensation rate of titania precursors. The collapse of the mesostructure upon the surfactant removal is effectively suppressed by the reinforcement of the pore walls with silica by exposing the as-deposited film to a vapor of a silicon alkoxide. The existence of a silica layer on the titania pore wall is proved from the distributions of Ti and Si estimated by the elemental analysis in high resolution electron microscopy. The obtained mesoporous titania-silica composite film exhibits a remarkable birefringence reflecting the highly anisotropic mesoporous structure and the high refractive index of titania that forms the pore wall. The Δn value estimated from the optical retardation and the film thickness is larger than 0.06, which cannot be achieved with the conventional mesoporous silica films with uniaxially aligned mesoporous structure even though the alignment of the pores in the films is perfect. These inorganic films with mesoscopic structural anisotropy will find many applications in the field of optics as phase plates with high thermal/chemical/mechanical stabilities.