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1.
Gastrointest Endosc ; 99(5): 826-829.e3, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38224820

RESUMO

BACKGROUND AND AIMS: There is no consensus on the effectiveness of prophylactic clipping after colonic cold snare polypectomy (CSP). This study aimed to evaluate the utility of prophylactic clipping in preventing delayed bleeding (DB) after colorectal CSP in patients on antithrombotic agents. METHODS: We retrospectively recruited consecutive patients on antithrombotic agents who underwent colorectal CSP in Chiba University Hospital. The DB rate was compared between patients with and without prophylactic clipping. RESULTS: The study included 133 patients (422 polyps) requiring prophylactic clipping and 85 patients (282 polyps) not requiring prophylactic clipping. There were no significant differences in DB and hematochezia rates between the groups. By weighted logistic regression analysis, the odds ratio of hematochezia was 0.557 (95% confidence interval, 0.225-1.378; P = .205) in patients without clipping compared to those with clipping. CONCLUSIONS: Prophylactic clipping may not be necessary to prevent DB after colorectal CSP in patients on antithrombotic agents.

2.
Gastrointest Endosc ; 100(4): 718-727, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38518979

RESUMO

BACKGROUND AND AIMS: Delayed bleeding (DB) is a major adverse event associated with colorectal endoscopic submucosal dissection (ESD) that sometimes causes difficulties in making decisions regarding endoscopic hemostasis. This study identified the factors that contribute to follow-up without endoscopic hemostasis when DB is suspected after colorectal ESD. METHODS: In total, 583 patients (603 tumors) who underwent ESD or hybrid ESD for colorectal tumors at Chiba University Hospital between June 2009 and January 2022 were retrospectively registered. Of these, 141 cases (141 tumors) with DB, and hematochezia or hemoglobin decrease ≥2 g/dL after colorectal ESD, were analyzed. The DB group was divided into the Hemostasis group (H group; endoscopic hemostasis performed) and no-Hemostasis group (no-H group; no endoscopy performed, or endoscopy performed but no hemostasis performed after hematochezia or hemoglobin decrease). Univariate and multivariate logistic regression analyses were conducted to assess the factors contributing to follow-up. RESULTS: Thirty-one patients with 31 tumors were categorized into the H group, and 110 patients with 110 tumors were in the no-H group. Multivariate regression analysis revealed that date from ESD to first hematochezia ≤Day 3 (odds ratio, 4.55; 95% confidence interval, 1.44-14.33; P = .010) and bleeding duration ≤1 day (odds ratio, 3.35; 95% confidence interval, 1.35-8.34; P = .009) contributed to follow-up. CONCLUSIONS: In cases of DB after colorectal ESD, a bleeding duration ≤1 day or date from ESD to first hematochezia ≤Day 3 may contribute to follow-up observation without endoscopic hemostasis.


Assuntos
Colonoscopia , Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Hemostase Endoscópica , Hemorragia Pós-Operatória , Humanos , Ressecção Endoscópica de Mucosa/efeitos adversos , Masculino , Neoplasias Colorretais/cirurgia , Feminino , Idoso , Pessoa de Meia-Idade , Hemorragia Pós-Operatória/epidemiologia , Hemorragia Pós-Operatória/etiologia , Estudos Retrospectivos , Hemostase Endoscópica/métodos , Colonoscopia/efeitos adversos , Colonoscopia/métodos , Hemorragia Gastrointestinal/etiologia , Fatores de Tempo , Seguimentos , Idoso de 80 Anos ou mais , Modelos Logísticos , Hemoglobinas/análise , Hemoglobinas/metabolismo , Análise Multivariada
3.
Scand J Gastroenterol ; 59(8): 996-1001, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38847135

RESUMO

BACKGROUND: This study aimed to investigate the utility of intensive triamcinolone acetonide (TA) injections after extensive esophageal endoscopic submucosal dissection (ESD). METHODS: This retrospective study included 27 lesions in 27 consecutive patients who underwent ESD (ulcers encompassing ≥3/4 of the esophageal circumference) and received TA injections without oral steroid administration. Groups A and B included patients undergoing ESD with and without complete circumferential resection, respectively. All patients received TA injections (100 mg/session) immediately after ESD. In Group A, weekly based TA injections were performed until near-complete ulcer epithelialization. In Group B, patients did not receive additional injections or received weekly or biweekly TA injections. The primary outcome was stricture rate, and the secondary outcomes were the proportion of patients requiring endoscopic balloon dilation (EBD) and the number of TA injections. RESULTS: Group A included 7 lesions, and Group B included 20 lesions. The median (range) tumor lengths were 40 (30-90) and 45 (30-110) mm in Groups A and B, respectively. In Group A, the median circumferential resection diameter was 40 (20-80) mm. The stricture rate and the proportion of patients requiring EBD were 0 (0%) in Group A and 1 (5.0%) in Group B. The number of TA injection sessions was significantly higher in Group A than in Group B (8 [5-25] vs 1.5 [1-3]; p < 0.001). CONCLUSIONS: Intensive weekly or biweekly based TA injections might aid in preventing post-ESD stricture and the need for EBD in patients undergoing extensive resection involving the entire esophageal circumference.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Esofágicas , Estenose Esofágica , Triancinolona Acetonida , Humanos , Triancinolona Acetonida/administração & dosagem , Masculino , Feminino , Estudos Retrospectivos , Ressecção Endoscópica de Mucosa/efeitos adversos , Idoso , Pessoa de Meia-Idade , Neoplasias Esofágicas/cirurgia , Estenose Esofágica/prevenção & controle , Estenose Esofágica/etiologia , Idoso de 80 Anos ou mais , Esofagoscopia , Complicações Pós-Operatórias/prevenção & controle , Resultado do Tratamento , Glucocorticoides/administração & dosagem , Dilatação/métodos
4.
J Gastroenterol Hepatol ; 39(9): 1847-1855, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38747056

RESUMO

BACKGROUND AND AIM: The measurement of esophageal acid exposure time (AET) using combined multichannel intraluminal impedance-pH (MII-pH) tests is the gold standard for diagnosing gastroesophageal reflux disease (GERD). However, this catheter-based 24-h test can cause considerable patient discomfort. Our aim is to identify factors affecting AET and to develop a scoring model for predicting AET abnormalities before conducting the MII-pH test. METHODS: Of the 366 patients who underwent MII-pH test at two facilities in Japan and Vietnam, 255 patients who also had esophagogastroduodenoscopy and high-resolution manometry were included in this study. Logistic regression analysis was conducted using risk factors for AET > 6% identified from a derivation cohort (n = 109). A scoring system predicting AET > 6% was then constructed and externally validated with a separate cohort (n = 146). RESULTS: Three variables were derived from the prediction model: male gender, Hill grades III-IV, and weak mean distal contractile integrals. Based on these scores, patients were classified into low (0 point), intermediate (1-3 points), and high (4 points) risk groups. The probabilities of having an AET > 6% were 6%, 34%, and 100% for these groups, respectively. A score of < 1 excluded patients with abnormal AET, with a negative predictive value of 93.8% in the derivation cohort and 80.0% in the validation cohort. CONCLUSIONS: We derived and externally validated a prediction model for abnormal AET. This system could assist in guiding the appropriate treatment strategies for GERD.


Assuntos
Monitoramento do pH Esofágico , Refluxo Gastroesofágico , Manometria , Refluxo Gastroesofágico/diagnóstico , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Manometria/métodos , Impedância Elétrica , Idoso , Endoscopia do Sistema Digestório , Valor Preditivo dos Testes , Fatores Sexuais , Fatores de Risco , Modelos Logísticos , Japão/epidemiologia , Estudos de Coortes
5.
Dig Dis Sci ; 69(6): 2132-2139, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38622462

RESUMO

BACKGROUND: Vonoprazan, a potassium-competitive acid blocker, demonstrates more potent acid inhibition than proton pump inhibitors (PPIs). This study aimed to evaluate the effect of vonoprazan in patients with unproven gastroesophageal reflux disease (GERD) by comparing patients with vonoprazan-refractory heartburn with those with PPI-refractory heartburn. METHODS: This study included 104 consecutive patients with vonoprazan- or PPI-refractory heartburn (52 patients each), no erosive esophagitis on endoscopy and who underwent combined multichannel intraluminal impedance-pH (MII-pH) testing with vonoprazan/PPI discontinuation. Patients' backgrounds, symptom scores from four questionnaires, MII-pH results and high-resolution manometry results were compared between the two groups. RESULTS: The vonoprazan group demonstrated significantly higher GERD symptoms and scores of abdominal pain and diarrhea on the Gastrointestinal Symptom Rating Scale questionnaire. MII-pH results revealed that the vonoprazan group demonstrated 40.4%, 17.3%, and 42.3% and the PPIs group exhibited 26.9%, 17.3%, and 55.8% of abnormal acid reflux [true non-erosive reflux disease (NERD)], reflux hypersensitivity and functional heartburn, respectively. The vonoprazan group demonstrated higher true NERD rates but with no significant difference (p = 0.307). Among the vonoprazan group, eight patients with true NERD underwent another MII-pH test on vonoprazan, and all cases demonstrated normal acid exposure times (0.0% [0.0-0.3]). CONCLUSION: Patients with unproven GERD with vonoprazan-refractory heartburn demonstrated more symptoms, including not only GERD symptoms but also functional dyspepsia and irritable bowel syndrome symptoms, than those with PPI-refractory heartburn.


Assuntos
Refluxo Gastroesofágico , Azia , Inibidores da Bomba de Prótons , Pirróis , Sulfonamidas , Humanos , Inibidores da Bomba de Prótons/uso terapêutico , Azia/tratamento farmacológico , Azia/etiologia , Sulfonamidas/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Pirróis/uso terapêutico , Refluxo Gastroesofágico/tratamento farmacológico , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/fisiopatologia , Adulto , Idoso , Monitoramento do pH Esofágico , Resistência a Medicamentos , Manometria
6.
Esophagus ; 21(4): 546-551, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38844704

RESUMO

BACKGROUND: Recently, the incidence of achalasia has been increasing, but its cause remains unknown. This study aimed to examine the initial symptoms and the course of symptoms and to find new insights into the cause and course of the disease. METHODS: Altogether, 136 patients diagnosed with achalasia by high-resolution manometry (HRM) were enrolled. Questionnaires and chart reviews were conducted to investigate the initial symptoms, time from onset to diagnosis, and comorbidities, as well as the relationship between HRM results, time to diagnosis, and symptom severity. RESULTS: In total, 67 of 136 patients responded to the questionnaire. The median ages of onset and diagnosis were 42 and 58 years, respectively. The median time from onset to diagnosis was 78.6 months, with 25 cases (37.3%) taking > 10 years to be diagnosed. The symptom onset was gradual and sudden in 52 (77.6%) and 11 (16.4%) patients, respectively. Of the 11 patients with acute onset, three (27.3%) developed anhidrosis at the same time. There was no correlation between the time from onset to diagnosis and esophageal dilatation, resting LES pressure, or mean integrated relaxation pressure (IRP). No correlation was also found between the degree of symptoms and resting LES pressure or IRP. CONCLUSION: Esophageal achalasia can have acute or insidious onsets. This finding may help to elucidate the cause of achalasia.


Assuntos
Acalasia Esofágica , Manometria , Humanos , Acalasia Esofágica/diagnóstico , Acalasia Esofágica/fisiopatologia , Feminino , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Adulto , Idoso , Inquéritos e Questionários , Fatores de Tempo , Idade de Início , Adulto Jovem , Índice de Gravidade de Doença , Estudos Retrospectivos
7.
Biochem Biophys Res Commun ; 642: 192-200, 2023 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-36586187

RESUMO

Transforming growth factor (TGF)-ß/Smad pathway is implicated in the pathogenesis of liver fibrosis, a condition characterized by excessive deposition of extracellular matrix (ECM) proteins such as collagen in response to chronic inflammation. It has been reported that ceramide regulates collagen production through TGF-ß/Smad pathway activation. In this study, we examined whether miglustat, an inhibitor of glucosylceramide synthase, can suppress liver fibrosis by reducing TGF-ß/Smad pathway activity. Human hepatic stellate cells (HHSteCs) were cultured with TGF-ß and multiple miglustat concentrations to examine dose-dependent effects on the expression levels of ECM-related genes and Smad proteins. To evaluate the efficacy of miglustat for fibrosis mitigation, C57BL/6 mice were treated with carbon tetrachloride (CCl4) for 4 weeks to induce liver fibrosis, followed by combined CCl4 plus miglustat for a further 2 weeks. To examine if miglustat can also prevent fibrosis, mice were treated with CCl4 for 2 weeks, followed by CCl4 plus miglustat for 2 weeks. Miglustat dose-dependently downregulated expression of α-smooth muscle actin and ECM components in TGF-ß-treated HHSteCs. Both phosphorylation and nuclear translocation of Smad2 and Smad3 were also suppressed by miglustat treatment. Sirius-Red staining and hydroxyproline assays of model mouse liver samples revealed that miglustat reduced fibrosis, an effect accompanied by decreased expression of ECM. Our findings suggest that miglustat can both prevent and reverse liver fibrosis by inhibiting TGF-ß/Smad pathway.


Assuntos
Fator de Crescimento Transformador beta1 , Fator de Crescimento Transformador beta , Animais , Humanos , Camundongos , Tetracloreto de Carbono/farmacologia , Células Estreladas do Fígado/metabolismo , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Camundongos Endogâmicos C57BL , Transdução de Sinais , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
8.
Phys Rev Lett ; 130(10): 106501, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36962025

RESUMO

We show that effectively cold metastable states in one-dimensional photodoped Mott insulators described by the extended Hubbard model exhibit spin, charge, and η-spin separation. Their wave functions in the large on-site Coulomb interaction limit can be expressed as |Ψ⟩=|Ψ_{charge}⟩|Ψ_{spin}⟩|Ψ_{η-spin}⟩, which is analogous to the Ogata-Shiba states of the doped Hubbard model in equilibrium. Here, the η-spin represents the type of photo-generated pseudoparticles (doublon or holon). |Ψ_{charge}⟩ is determined by spinless free fermions, |Ψ_{spin}⟩ by the isotropic Heisenberg model in the squeezed spin space, and |Ψ_{η-spin}⟩ by the XXZ model in the squeezed η-spin space. In particular, the metastable η-pairing and charge-density-wave (CDW) states correspond to the gapless and gapful states of the XXZ model. The specific form of the wave function allows us to accurately determine the exponents of correlation functions. The form also suggests that the central charge of the η-pairing state is 3 and that of the CDW phase is 2, which we numerically confirm. Our study provides analytic and intuitive insights into the correlations between active degrees of freedom in photodoped strongly correlated systems.

9.
Gastrointest Endosc ; 97(6): 1052-1058.e2, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36649746

RESUMO

BACKGROUND AND AIMS: Gastric submucosal tumors (SMTs) are treated or monitored according to GI stromal tumor guidelines, but the adequacy of the guidelines has not been thoroughly examined. We investigated the long-term course of gastric SMTs to determine the validity of guideline-based follow-up methods and the factors contributing to their size increase. METHODS: This study included gastric SMTs diagnosed as GI mesenchymal tumors (GIMTs) by using EUS and followed up with EUS. The percentage and speed of GIMT enlargement and factors associated with the enlargement were investigated by using the Cox proportional hazards model. RESULTS: From January 1994 to May 2022, a total of 925 gastric SMTs were evaluated with EGD, and 231 SMTs were diagnosed as GIMTs. Of the 231 GIMTs, 145 were examined by EUS more than twice and were followed up for >6 months. The mean ± standard deviation follow-up period was 5.20 ± 4.04 years (range, 0.5-17.3 years), with 39 (26.9%) of 145 GIMTs increasing in size with a mean doubling time of 3.60 ± 3.37 years. A multivariate analysis of factors influencing tumor growth revealed that irregular extraluminal borders were an increasing factor (hazard ratio, 3.65; 95% confidence interval, 1.26-10.52), initial tumor size ≤9.5 mm (hazard ratio, .23; 95% confidence interval, 0.07-0.77) was a nonincreasing factor, and GIMTs with calcification (n = 13) did not increase in size. CONCLUSIONS: Tumor growth in gastric GIMTs <9.5 mm in diameter and/or with calcification is rare. Follow-up intervals for these lesions could be extended.


Assuntos
Neoplasias Gastrointestinais , Tumores do Estroma Gastrointestinal , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/cirurgia , Tumores do Estroma Gastrointestinal/patologia , Estudos Retrospectivos , Mucosa Gástrica/diagnóstico por imagem , Mucosa Gástrica/patologia , Resultado do Tratamento
10.
J Gastroenterol Hepatol ; 38(9): 1546-1551, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37194195

RESUMO

BACKGROUND AND AIM: Little is known about genetic mutations in the regenerated mucosa (RM) after endoscopic resection (ER) of esophageal carcinoma. Thus, this study investigates the status of genetic variation in RM after ER of esophageal squamous cell carcinoma (ESCC). METHODS: The study cohort included 19 patients with ESCC. We used an esophageal carcinoma panel to identify target sequences for squamous cell carcinoma (SCC), background mucosa (BM), and RM after ER of ESCC. We used OncoKB to check whether each mutation was a putative driver. RESULTS: We identified 77 mutations of 32 genes in SCC, 133 mutations of 34 genes in BM, and 100 mutations of 29 genes in RM. Putative driver mutations were identified in 20 mutations in 14 cases in SCC, 16 mutations in 10 cases in BM, and 7 mutations in 11 cases in RM. The rate of putative driver mutations to total mutations was significantly lower in RM (26% in SCC vs 12% in BM vs 7% in RM, P = 0.009). Additionally, the rate of cases with TP53 putative driver mutations was significantly lower in RM (63% in SCC vs 37% in BM vs 16% in RM, P = 0.011). The percentage of putative driver mutations and the percentage of cases with a putative driver of TP53 were significantly lower in RM. CONCLUSION: Esophageal RM after ER of ESCC could have a lower risk of carcinogenesis.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/cirurgia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologia , Carcinógenos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/patologia , Carcinogênese , Mucosa
11.
Digestion ; 104(4): 328-334, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36893744

RESUMO

BACKGROUND: Patients with inflammatory bowel diseases (IBD) can develop extraintestinal manifestations (EIMs) during the disease course, which sometimes impact their quality of life. OBJECTIVES: This study aimed to clarify the prevalence and types of EIMs using a hospital-based IBD cohort in Japan. METHODS: A patient cohort with IBD was established in 2019, as participated by 15 hospitals in Chiba Prefecture of Japan. Using this cohort, the prevalence and types of EIMs, which are defined based on previous reports and the Japanese guidelines, were investigated. RESULTS: This cohort enrolled 728 patients, including 542 ulcerative colitis (UC) and 186 Crohn's disease (CD). Of these patients with IBD, 10.0% were identified with one or more EIMs (57 (10.5%) with UC and 16 (8.6%) with CD). Arthropathy and arthritis were the most common EIM in 23 (4.2%) patients with UC, followed by primary sclerosing cholangitis (PSC) (2.6%). Arthropathy and arthritis were also the most common in patients with CD, but no cases of PSC were observed. EIMs were more frequently observed in patients with IBD treated by specialists than in those treated by non-specialists (12.7% vs. 5.5%, p = 0.011). The incidence of EIMs in patients with IBD was not significantly different over time. CONCLUSIONS: The prevalence and types of EIMs in our hospital-based cohort in Japan did not significantly differ from those reported in previous or Western studies. However, the incidence might be underestimated due to the limited ability of non-IBD specialists to discover and describe EIMs in patients with IBD.


Assuntos
Artrite , Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Artropatias , Humanos , Artrite/epidemiologia , Artrite/etiologia , Colite Ulcerativa/complicações , Colite Ulcerativa/epidemiologia , Doença de Crohn/complicações , Doença de Crohn/epidemiologia , População do Leste Asiático , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/epidemiologia , Artropatias/etiologia , Artropatias/complicações , Qualidade de Vida
12.
Dig Dis Sci ; 68(10): 3963-3973, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37658209

RESUMO

BACKGROUND AND AIMS: This randomized controlled trial (RCT) was designed to evaluate the short-term outcomes of underwater endoscopic mucosal resection (UEMR) and endoscopic submucosal dissection (ESD) of 21-30 mm colonic polyps. METHOD: We conducted a single-center RCT. Patients diagnosed with suspected colorectal intramucosal carcinoma (21-30 mm and adaptable for both UEMR and ESD) were randomly assigned to the UEMR and ESD groups at a 1:1 ratio. The primary endpoint was the R0 resection rate. We independently performed one-sample tests against the set threshold for each treatment. The significance level was set at p = 0.224. RESULT: Eleven polyps each in the UEMR and ESD groups, respectively, were analyzed. The R0 resection rate (%) was 36 (95% confidence interval 11-69) and 100 (72-100) for UEMR and ESD, respectively, with a significant difference between the two groups (p = 0.002). The p-value against the set threshold for UEMR was 0.743, whereas that for ESD was < 0.001 (one-sample binomial test). The en bloc resection rates (%) were 82 (48-97) and 100 (72-100) for UEMR and ESD, respectively; however, no significant difference was observed (p = 0.167). The mean treatment time (min) was significantly shorter in the UEMR group (8 ± 6) than in the ESD group (48 ± 29) (p = 0.001). CONCLUSION: ESD could achieve a high R0 resection rate, while the en bloc resection rate was comparable between the two treatment techniques with less burden on patients undergoing UEMR for 21-30-mm colorectal polyps. CLINICAL TRIAL REGISTRATION: The study was registered at the Japan Registry of Clinical Trial as jRCT1030210015 and jRCT1030210177.


Assuntos
Pólipos do Colo , Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Humanos , Pólipos do Colo/cirurgia , Neoplasias Colorretais/cirurgia , Estudos de Viabilidade , Japão
13.
Nano Lett ; 22(15): 6105-6111, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35883274

RESUMO

Organic material-based thermal switch is drawing much attention as one of the key thermal management devices in organic electronic devices. This study aims at tuning the switching temperature (TS) of thermal conductivity by using liquid crystalline block copolymers (BCs) with different order-order transition temperature (Ttr) related to the types of mesogens in the side chain. The BC films with low Ttr of 363 K and high Ttr of 395 K exhibit reversible thermal conductivity switching behaviors at TS of ∼360 K and ∼390 K, respectively. The BC films also exhibit thermal conductivity variation originating from the anisotropy of the internal structures: poly(ethylene oxide) domains and liquid crystals. These results demonstrate that the switching behavior is attributed to an order-order transition between BC films with vertically arranged cylinder domains and the ones with ordered sphere domains. This highlights that BCs become a promising thermal conductivity switching material with tailored TS.

14.
Gastric Cancer ; 25(2): 392-400, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34652556

RESUMO

BACKGROUND: This study aimed to prevent missing gastric cancer and point out low-quality images by developing a double-check support system (DCSS) for esophagogastroduodenoscopy (EGD) still images using artificial intelligence. METHODS: We extracted 12,977 still EGD images from 855 cases with cancer [821 with early gastric carcinoma (EGC) and 34 malignant lymphoma (ML)] and developed a lesion detection system using 10,994 images. The remaining images were used as a test dataset. Additional validation was performed using a new dataset containing 50 EGC and 1,200 non-GC images by comparing the interpretation of ten endoscopists (five trainees and five experts). Furthermore, we developed another system to detect low-quality images, which are not suitable for diagnosis, using 2198 images. RESULTS: In the validation of 1983 images from the 124 cancer cases, the DCSS diagnosed cancer with a sensitivity of 89.2%, positive predictive value (PPV) of 93.3%, and an accuracy of 83.3%. EGC was detected in 93.2% and ML in 92.5% of cases. Comparing with the endoscopists, sensitivity was significantly higher in the DCSS, and the average diagnostic time was significantly shorter using the DCSS than that by the trainees. The sensitivity, specificity, PPV, and accuracy in detecting low-quality images were 65.8%, 93.1%, 79.6%, and 85.2% for "Blur" and 57.8%, 91.7%, 82.2%, and 78.1% for "Mucus adhesion," respectively. CONCLUSIONS: The DCSS showed excellent capability in detecting lesions and pointing out low-quality images.


Assuntos
Inteligência Artificial , Neoplasias Gástricas , Detecção Precoce de Câncer/métodos , Endoscopia , Humanos , Valor Preditivo dos Testes , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia
15.
J Gastroenterol Hepatol ; 37(1): 75-80, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34409657

RESUMO

BACKGROUND AND AIM: The effectiveness of cold snare polypectomy (CSP) for superficial non-ampullary duodenal epithelial tumors (SNADETs) regarding long-term outcomes is not fully clarified. This study aimed to investigate long-term outcomes of CSP for SNADETs. METHODS: Patients diagnosed with sporadic SNADETs and treated with CSP at Chiba University Hospital between March 2015 and May 2018 were retrospectively analyzed. Long-term outcomes, short-term outcomes, and adverse events were investigated. RESULTS: In total, 35 patients with 46 lesions were included. The en-bloc resection rate was 97.8%. Thirty-seven lesions (80.4%) were diagnosed as adenomatous. The R0 resection rate for adenomatous lesions was 70.3%. Follow-up investigations more than 12 months after CSP were completed for 35 adenomatous lesions (94.6%). The median observation period after CSP was 48 months. One patient whose observation period was only 3 months died from chronic heart failure with cardiac sarcoidosis 6 months after CSP. No patient died from SNADETs. The relapse-free survival rate at 12 months after CSP was 97.1%. One recurrence (2.7%) was observed 12 months after CSP. We removed the recurrence lesion with CSP and cold forceps polypectomy. No new recurrence occurred within the observation period. No perforation or post-operative bleeding occurred for CSP. CONCLUSIONS: Cold snare polypectomy for diminutive and small SNADETs is a safe and useful procedure with a high en-bloc resection rate and long-term local control capability.


Assuntos
Adenocarcinoma , Colectomia , Pólipos do Colo , Neoplasias Duodenais , Adenocarcinoma/cirurgia , Colectomia/efeitos adversos , Colectomia/métodos , Pólipos do Colo/cirurgia , Neoplasias Duodenais/cirurgia , Humanos , Estudos Retrospectivos , Resultado do Tratamento
16.
J Gastroenterol Hepatol ; 37(6): 1083-1089, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35263810

RESUMO

BACKGROUND AND AIM: Anti-tumor necrosis factor (TNF)α antibody (ATA) and biologics/molecular targeted agents with other mechanisms (non-ATA) are currently available for refractory ulcerative colitis (UC). However, the knowledge about optimal drug selection after the initial treatment with ATA failure is lacking. This study assessed whether the response to the initial ATA could be a basis for selecting subsequent agents in UC patients. METHODS: Ulcerative colitis patients treated with ATA or non-ATA as the subsequent biologic after the failure of initial ATA were retrospectively analyzed. The efficacy at 14 weeks was examined according to the response to initial ATA. RESULTS: Of 163 patients treated with the first ATA, the efficacy of subsequent ATA and non-ATA was evaluated in 63 and 36, respectively. Remission and response to subsequent-line therapy, regardless of ATA or non-ATA, were lower in patients with primary nonresponse (PNR) to initial ATA than in patients with efficacy to initial ATA (33.3% vs 69.2%, P < 0.01). In patients with PNR to initial ATA, the remission rate with subsequent ATA was significantly lower than with subsequent non-ATA (4.3% vs 26.3%, P = 0.04). In patients who showed efficacy to initial ATA, the remission rate with subsequent ATA was also lower than that with subsequent non-ATA (30.6% vs 56.3%, P = 0.08). PNR with initial ATA was the predictor of PNR to subsequent ATA (odds ratio: 5.62, 95% confidence interval: 1.50-21.7). CONCLUSION: Non-ATA may be suitable in UC patients as the subsequent biologics regardless of the outcome of the first ATA.


Assuntos
Produtos Biológicos , Colite Ulcerativa , Produtos Biológicos/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Humanos , Infliximab/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Fator de Necrose Tumoral alfa
17.
Int J Mol Sci ; 23(14)2022 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-35887229

RESUMO

Previous RNA immunoprecipitation followed by proteomic approaches successfully demonstrated that Embryonic Lethal, Abnormal Vision, Drosophila-Like 1 (ELAVL1) interacts with hepatitis B virus (HBV)-derived RNAs. Although ELAVL family proteins stabilize AU-rich element (ARE)-containing mRNAs, their role in HBV transcription remains unclear. This study conducted loss-of-function assays of ELAVL1 for inducible HBV-replicating HepAD38 cells and HBx-overexpressed HepG2 cells. In addition, clinicopathological analyses in primary hepatocellular carcinoma (HCC) surgical samples were also conducted. Lentivirus-mediated short hairpin RNA knockdown of ELAVL1 resulted in a decrease in both viral RNA transcription and production of viral proteins, including HBs and HBx, probably due to RNA stabilization by ELAVL1. Cell growth of HepAD38 cells was more significantly impaired in ELAVL1-knockdown than those in the control group, with or without HBV replication, indicating that ELAVL1 is involved in proliferation by factors other than HBV-derived RNAs. Immunohistochemical analyses of 77 paired HCC surgical specimens demonstrated that diffuse ELAVL1 expression was detected more frequently in HCC tissues (61.0%) than in non-tumor tissues (27.3%). In addition, the abundant expression of ELAVL1 tended to affect postoperative recurrence in HBV-related HCC patients. In conclusion, ELAVL1 contributes not only to HBV replication but also to HCC cell growth. It may be a potent therapeutic target for HBV-related HCC treatment.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/metabolismo , Drosophila/genética , Células Hep G2 , Hepatite B/complicações , Hepatite B/genética , Hepatite B/metabolismo , Vírus da Hepatite B/fisiologia , Humanos , Neoplasias Hepáticas/metabolismo , Proteômica , RNA Viral/genética , RNA Viral/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Transativadores/metabolismo , Proteínas Virais Reguladoras e Acessórias/metabolismo , Replicação Viral/genética
18.
Phys Rev Lett ; 127(12): 127702, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34597072

RESUMO

We show that in electron-hole bilayers with excitonic orders arising from conduction and valence bands formed by atomic orbitals that have different parities, nonzero interlayer tunneling leads to a second-order Josephson effect. This means the interlayer electrical current is related to the phase of the excitonic order parameter as J=J_{c}sin2θ instead of J=J_{c}sinθ and that the system has two degenerate ground states at θ=0,π that can be switched by an interlayer voltage pulse. When generalized to a three dimensional stack of alternating electron-hole planes or a two dimensional stack of chains, the ac Josephson effect implies that electric field pulses perpendicular to the layers and chains can steer the order parameter phase between the two degenerate ground states, making these devices ultrafast memories. The order parameter steering also applies to the excitonic insulator candidate Ta_{2}NiSe_{5}.

19.
Phys Rev Lett ; 127(12): 127402, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34597083

RESUMO

We investigate the bulk photovoltaic effect, which rectifies light into electric current, in a collective quantum state with correlation driven electronic ferroelectricity. We show via explicit real-time dynamical calculations that the effect of the applied electric field on the electronic order parameter leads to a strong enhancement of the bulk photovoltaic effect relative to the values obtained in a conventional insulator. The enhancements include both resonant enhancements at sub-band-gap frequencies, arising from excitation of optically active collective modes, and broadband enhancements arising from nonresonant deformations of the electronic order. The deformable electronic order parameter produces an injection current contribution to the bulk photovoltaic effect that is entirely absent in a rigid-band approximation to a time-reversal symmetric material. Our findings establish that correlation effects can lead to the bulk photovoltaic effect and demonstrate that the collective behavior of ordered states can yield large nonlinear optical responses.

20.
Gastrointest Endosc ; 93(3): 647-653, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32735946

RESUMO

BACKGROUND AND AIMS: Endoscopic treatment is recommended for low-grade dysplasia (LGD), high-grade dysplasia (HGD), and colorectal cancer (CRC) with submucosal (SM) invasion <1000 µm. However, diagnosis of invasion depth requires experience and is often difficult. This study developed and evaluated a novel computer-aided diagnosis (CAD) system to determine whether endoscopic treatment is appropriate for colorectal lesions using only white-light endoscopy (WLE). METHODS: We extracted 3442 images from 1035 consecutive colorectal lesions (105 LGDs, 377 HGDs, 107 CRCs with SM <1000 µm, 146 CRCs with SM ≥1000 µm, and 300 advanced CRCs). All images were WLE, nonmagnified, and nonstained. We developed a novel CAD system using 2751 images; the remaining 691 images were evaluated by the CAD system as a test set. The capability of the CAD system to distinguish endoscopically treatable lesions and untreatable lesions was assessed and compared with the results from 2 trainees and 2 experts. RESULTS: The CAD system distinguished endoscopically treatable from untreatable lesions with 96.7% sensitivity, 75.0% specificity, and 90.3% accuracy. These values were significantly higher than those from trainees (92.1%, 67.6%, and 84.9%; P < .01, <.01, and <.01, respectively) and were comparable with those from experts (96.5%, 72.5%, and 89.4%, respectively). Trainees assisted by the CAD system demonstrated a diagnostic capability comparable with that of experts. CONCLUSIONS: The CAD system had good diagnostic capability for making treatment decisions for colorectal lesions. This system may enable a more convenient and accurate diagnosis using only WLE.


Assuntos
Neoplasias Colorretais , Diagnóstico por Computador , Neoplasias Colorretais/diagnóstico por imagem , Computadores , Endoscopia , Humanos , Hiperplasia
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