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1.
J Magn Reson Imaging ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38996369

RESUMO

BACKGROUND: Turbo spin-echo (TSE) diffusion-weighted imaging (DWI) sequences may reduce susceptibility artifacts and image distortion in sellar region, allowing better visualization of small pituitary lesions, and may be used to assist in the diagnosis of pituitary microadenomas. PURPOSE: To explore the application value of conventional MRI combined with DWI sequences in the diagnosis of microprolactinomas. STUDY TYPE: Prospective. POPULATION: Thirty-four patients in microprolactinomas with high signal on T2WI (HT2-PRL) group (34 females, 34 ± 7 years), 26 patients in microprolactinomas with equal or low signal on T2WI (ELT2-PRL) group (21 females, 34 ± 7 years), 35 patients with hyperprolactinemia (33 females, 32 ± 8 years), and 30 normal controls (25 females, 31 ± 7 years). FIELD STRENGTH/SEQUENCE: TSE sequence at 3 T. ASSESSMENT: Pituitary morphological parameters (such as length and volume), dynamic contrast-enhanced parameters (such as time to peak) and the apparent diffusion coefficients (ADCs) were measured in each group. STATISTICAL TESTS: ANOVA and Mann-Whitney U test were used to compare parameters among groups. Spearman's coefficient was used to evaluate the correlation between variables. ROC analysis was used to assess the performance of the parameters. A P-value <0.05 was considered statistically significant. RESULTS: The pituitary volume of patients in HT2-PRL, ELT2-PRL, and hyperprolactinemia group were 831.00 (747.60, 887.60), 923.63 ± 219.34, and 737.20 (606.40, 836.80) mm3. The pituitary maximum height in these three groups were 7.03 (6.43, 8.63), 8.03 ± 1.41, and 6.63 ± 1.28 mm, respectively. The lesion ADC value was significantly correlated with T2 relative signal intensity (the ratio of signal intensity of microprolactinoma or anterior pituitary to left temporal cortex) (r = 0.821). Compared with patients with hyperprolactinemia, the diagnostic efficacy of T2 relative signal intensity was higher in HT2-PRL group, with an AUC of 0.954, whereas the ADC value was the highest in ELT2-PRL group, with an AUC of 0.924. CONCLUSION: DWI sequences can be used to assist in the diagnosis of pituitary microadenomas. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.

2.
Clin Gastroenterol Hepatol ; 21(5): 1205-1213.e2, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36075502

RESUMO

BACKGROUND & AIMS: Esophagogastroduodenoscopy (EGD) is effective in reducing gastric cancer mortality through detection of early-stage cancer in areas with a high prevalence of gastric cancer. Although the risk of post-endoscopy advanced gastric cancer (AGC) is low, interval AGC remains a concern. We investigated the characteristics and predictors of interval AGC after negative EGD. METHODS: We included 1257 patients with gastric cancer within 6 to 36 months of a "cancer-negative" index EGD between 2005 and 2021 at a tertiary university hospital in South Korea. Observation time on the index EGD was used as a quality indicator. We compared the clinical and endoscopic characteristics and quality indicators between interval AGC and screen-detected early gastric cancer (EGC). RESULTS: Within 6 to 36 months of negative EGD, 102 AGCs (8.1%) and 1155 EGCs (91.9%) were identified. The percentage of patients with shorter observation time (<3 minutes) in the index EGD was higher in the interval AGC group than in the detected EGC group (P = .002). A multivariable analysis comparing screen-detected EGD and interval AGC was adjusted for age, sex, family history of gastric cancer, H. pylori status, endoscopic findings, and endoscopy-related factors including gastric observation time and interval time. A shorter observation time (<3 minutes) (odds ratio, 2.27; 95% confidence interval, 1.20-4.30), and interval time >2 years (odds ratio, 1.84; 95% confidence interval, 1.04-3.24) were associated with an increased risk of interval AGC. CONCLUSION: A shorter observation time during index EGD is an important predictor of interval AGC. Further, withdrawal time longer than 3 minutes may be a quality indicator for screening EGD.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/epidemiologia , Endoscopia do Sistema Digestório , Endoscopia Gastrointestinal , República da Coreia/epidemiologia , Hospitais Universitários
3.
Am J Obstet Gynecol ; 228(4): 382-394, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36088986

RESUMO

Gastroparesis is a functional gastrointestinal disorder that more commonly affects women, with most cases being diagnosed during childbearing age. However, there is a paucity of data and guidelines to specifically highlight the epidemiology, disease course, maternal and fetal impact, and the management of existing gastroparesis during pregnancy. Apart from metoclopramide, there is no approved therapy specifically indicated for gastroparesis. More importantly, pregnant and breastfeeding women are excluded from clinical trials evaluating pharmacologic agents in the management of gastroparesis. This poses a real challenge to healthcare providers in counseling and managing patients with gastroparesis. In this systematic review, we summarize the current available literature and the knowledge gaps in the impact of pregnancy on gastroparesis and vice versa. We also highlight the efficacy and safety profiles of available pharmacologic and nonpharmacologic therapies in the management of patients with gastroparesis, with emphasis on judicious use of dietary approaches that are deemed relatively safe during pregnancy.


Assuntos
Gastroparesia , Gravidez , Humanos , Feminino , Gastroparesia/tratamento farmacológico , Fármacos Gastrointestinais/efeitos adversos , Metoclopramida/uso terapêutico
4.
Nature ; 545(7652): 48-53, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28445462

RESUMO

In vitro models of the developing brain such as three-dimensional brain organoids offer an unprecedented opportunity to study aspects of human brain development and disease. However, the cells generated within organoids and the extent to which they recapitulate the regional complexity, cellular diversity and circuit functionality of the brain remain undefined. Here we analyse gene expression in over 80,000 individual cells isolated from 31 human brain organoids. We find that organoids can generate a broad diversity of cells, which are related to endogenous classes, including cells from the cerebral cortex and the retina. Organoids could be developed over extended periods (more than 9 months), allowing for the establishment of relatively mature features, including the formation of dendritic spines and spontaneously active neuronal networks. Finally, neuronal activity within organoids could be controlled using light stimulation of photosensitive cells, which may offer a way to probe the functionality of human neuronal circuits using physiological sensory stimuli.


Assuntos
Encéfalo/citologia , Vias Neurais/fisiologia , Neurogênese , Organoides/citologia , Organoides/efeitos da radiação , Linhagem Celular , Separação Celular , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Dendritos , Perfilação da Expressão Gênica , Humanos , Técnicas In Vitro , Luz , Rede Nervosa/citologia , Rede Nervosa/efeitos da radiação , Vias Neurais/citologia , Vias Neurais/efeitos da radiação , Especificidade de Órgãos , Organoides/crescimento & desenvolvimento , Células Fotorreceptoras de Vertebrados/citologia , Células-Tronco Pluripotentes/citologia , Retina/citologia , Retina/metabolismo , Análise de Sequência de RNA , Análise de Célula Única , Fatores de Tempo , Transcriptoma
5.
Microsc Microanal ; 29(2): 658-664, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37749715

RESUMO

Telocytes (TCs), a novel type of interstitial cells, are characterized by their smaller cellular body and extremely long, thin processes which are called telopodes (Tps). They have been described in multiple organs from diverse animals. Currently, the existence of TCs in rat pars distalis (PD) has remained unexplored. This investigation was undertaken to visualize the distribution and structural features of TCs in the PD using immunofluorescence (IF) and further validated by transmission electron microscopy (TEM). HE staining revealed the presence of interstitial cells in the peri-sinusoidal vessels spaces of the PD. Using IF, CD34/vimentin double-positive interstitial cells were identified as TCs in accordance with identification standards. TEM further verified the presence of TCs based on their unique ultrastructural features. TCs exhibited communication structures including cell connections and extracellular vesicles (EVs). Interestingly, TCs were in close proximity to the nerves. Most importantly, Tps extended toward the nerves, blood vessels, and glandular cells. TCs could be the structural foundation of a third regulatory system in rat PD according to the tight connections of TCs with sinusoid vessels, glandular cells, EVs and most crucially the nerves. Taken together, these morphological and structural findings demonstrate that TCs are vital components of the rat PD.


Assuntos
Células Intersticiais de Cajal , Telócitos , Animais , Ratos , Células Epiteliais , Microscopia Eletrônica de Transmissão , Hipófise
6.
Dig Endosc ; 35(7): 869-878, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36997298

RESUMO

OBJECTIVES: It is unclear whether renal insufficiency (RI) itself is a risk factor for adverse outcomes after gastric endoscopic submucosal dissection (ESD). We aimed to evaluate the safety and efficacy of gastric ESD in patients with and without RI using propensity score-matching analysis. METHODS: In all, 4775 patients with 4775 early gastric cancer lesions undergoing ESD were analyzed. 1:1 propensity score-matching was performed between patients with and without RI using 12 variables. After matching, logistic regression and survival analyses were performed for short- and long-term outcomes of ESD, respectively. RESULTS: The matching yielded 188 pairs of patients with and without RI. In both univariable and multivariable analyses, the presence of RI was not significantly associated with postprocedural bleeding (unadjusted odds ratio 1.81, 95% confidence interval 0.74-4.42; adjusted odds ratio 1.86, 95% confidence interval 0.74-4.65, respectively). When RI patients were subclassified into patients with estimated glomerular filtration rate (eGFR) 30-59 mL/min/1.73 m2 and eGFR <30 mL/min/1.73 m2 , no significant differences in bleeding rates were found compared to their matched controls in both groups. Perforation, en bloc resection, en bloc and R0 resection, and curative resection rates of RI patients were 2.1%, 98.4%, 91.0%, and 78.2%, respectively, which were comparable to those of non-RI patients. During a median follow-up of 119 months, there was no difference in gastric cancer-specific survival between patients with and without RI (P = 0.143). CONCLUSION: The outcomes of ESD were comparable in patients with and without RI. Decreased renal function itself may not be a reason to keep patients with RI from receiving gastric ESD.


Assuntos
Ressecção Endoscópica de Mucosa , Insuficiência Renal , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Estudos Retrospectivos , Pontuação de Propensão , Resultado do Tratamento , Insuficiência Renal/etiologia , Insuficiência Renal/patologia , Mucosa Gástrica/cirurgia , Mucosa Gástrica/patologia
7.
Molecules ; 29(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38202810

RESUMO

The presence of massive amounts of toxic volatiles and smoke during combustion is a very serious problem facing epoxy resin (EP) composites. Therefore, flame retardants (FRs) can simultaneously enhance flame retardancy and reduce the release of smoke and fatal gases. Herein, a novel sulfur-phosphorous reactive flame retardant (SPMS) was synthesized for epoxy resin. The high efficiency of smoke suppression and flame retardancy of the EP/SPMS-APP hybrid was investigated using a cone calorimeter, a vertical burning test, and limited oxygen index measurements. Compared with those of pure EP, the composite with 20 wt% SPMS-APP reduced the peak heat release rate (pHRR), the peak smoke production rate (SPR), and total smoke production rate (TSR) by 82%, 94%, and 84%, respectively. The results showed a remarkable suppressed effect of alleviating the fire hazard of EP using a sulfur-phosphorus flame retardant.

8.
Angew Chem Int Ed Engl ; 62(18): e202216049, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36863996

RESUMO

Typical n-type conjugated polymers are based on fused-ring electron-accepting building blocks. Herein, we report a non-fused-ring strategy to design n-type conjugated polymers, i.e. introducing electron-withdrawing imide or cyano groups to each thiophene unit of a non-fused-ring polythiophene backbone. The resulting polymer, n-PT1, shows low LUMO/HOMO energy levels of -3.91 eV/-6.22 eV, high electron mobility of 0.39 cm2  V-1 s-1 and high crystallinity in thin film. After n-doping, n-PT1 exhibits excellent thermoelectric performance with an electrical conductivity of 61.2 S cm-1 and a power factor (PF) of 141.7 µW m-1 K-2 . This PF is the highest value reported so far for n-type conjugated polymers and this is the first time for polythiophene derivatives to be used in n-type organic thermoelectrics. The excellent thermoelectric performance of n-PT1 is due to its superior tolerance to doping. This work indicates that polythiophene derivatives without fused rings are low-cost and high-performance n-type conjugated polymers.

9.
Opt Express ; 30(25): 44580-44593, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36522880

RESUMO

Depth of field (DOF) and resolution are mutually restricted in integral imaging (II) display. To overcome the trade-offs, we propose an II display system that simultaneously enhances the DOF and resolution. The system consists of a transmissive mirror device (TMD), a semi-transparent mirror (STM), and two II display units. Each II display unit consists of a 4K display screen and a micro-lens array (MLA). Benefiting from the parallel placement of the TMD and the STM, two central depth planes are reconstructed, which effectively enhances the DOF. Meanwhile, the resolution in the overlapping DOF region is increased to two times due to the interpolation of the light field information from two II display units. The impact of the distance between the two II display units and the TMD on the 3D image quality is analyzed. In geometric optics, a distance between the II two display units and the TMD is optimized to eliminate ghost images. In wave optics, a distance is optimized to eliminate 3D pixel gaps by exploiting the diffraction effect of the TMD. Both the geometric and wave optics are considered simultaneously to obtain a high-quality 3D image without ghost images and 3D pixel gaps. A DOF and resolution-enhanced II display system is developed, and the experimental results verify its feasibility.

10.
Gastrointest Endosc ; 95(2): 281-290, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34555386

RESUMO

BACKGROUND AND AIMS: The optimal management of upper GI (UGI) leaks and perforations remains controversial. Endoscopic vacuum therapy (EVT) is a new alternative endoscopic treatment that has recently shown a high rate of successful closure of UGI leaks and perforations. However, only few reports have been made on the factors that affect clinical success rates. METHODS: Four referral hospitals participated in this retrospective multicenter study. Between September 2015 and February 2020, 119 patients who underwent EVT for a UGI perforation or leak were included. We retrospectively evaluated the clinical outcomes of EVT and the factors associated with EVT failure. Neoadjuvant treatments included chemotherapy, radiotherapy, or chemoradiotherapy before surgery, and the intraluminal method meant that the sponge was placed directly onto the defect within the lumen of UGI tract. RESULTS: Among 119 patients, 84 showed clinical success (70.6%). Eighty-nine patients (74.8%) underwent EVT as primary therapy and 30 patients as rescue therapy. On multivariate analysis, neoadjuvant treatment and the intraluminal method were significant independent risk factors for EVT failure. During the follow-up period (median, 8.46 months), stenosis occurred in 22 patients (18.5%). The overall survival rate of the EVT success group was significantly higher than that of the EVT failure group. Twenty-two patients died because of non-EVT-related causes, and 7 patients died because of leakage-related adverse events. No death was caused by the EVT itself. CONCLUSIONS: EVT is a promising treatment method for UGI leaks and perforations. Further studies are needed to establish the indications for successful EVT.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Trato Gastrointestinal Superior , Fístula Anastomótica/cirurgia , Humanos , Tratamento de Ferimentos com Pressão Negativa/métodos , Estudos Retrospectivos , Falha de Tratamento , Resultado do Tratamento
11.
BMC Gastroenterol ; 22(1): 157, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35351022

RESUMO

BACKGROUND: Primary malignant melanoma of esophagus (PMME) is an extremely rare disease with poor prognosis. We aimed to determine the clinical characteristics and treatment outcomes of patients with PMME. METHODS: We retrospectively reviewed 17 patients diagnosed with PMME in Samsung Medical Center between 2000 and 2020 with median 34 months of follow-up. Survival outcomes were analyzed with Kaplan-Meier method. RESULTS: 15 patients (88.2%) were male and the most common presenting symptom was dysphagia (9/17, 52.9%). On endoscopy, tumors were mass-forming in 15 patients (88.2%) and diffusely infiltrative in two patients (11.8%). Lesions were melanotic in 13 patients (76.5%) and amelanotic in four patients (23.5%). The most common tumor location was lower esophagus (11/17, 64.7%). The disease was metastatic at the time of diagnosis in four patients (23.5%). As for treatment, 10 patients (58.8%) underwent surgery. In all 17 patients, the median overall survival was 10 months. In surgically treated patients, all patients experienced recurrence and the median disease-free survival was 4 months. There was no statistical difference in overall survival between patients with or without surgery. Patients with diffusely infiltrative tumor morphology had better overall survival compared to those with mass-forming tumor morphology (P = 0.048). Two patients who received immunotherapy as the first-line treatment without surgery showed overall survival of 34 and 18 months, respectively. CONCLUSIONS: As radical resection for patients with PMME does not guarantee favorable treatment outcomes, novel treatment strategy is required. Further large-scale studies are warranted to determine the efficacy of immunotherapy for patients with PMME.


Assuntos
Melanoma , Neoplasias Cutâneas , Esôfago/patologia , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/patologia , Melanoma/terapia , Estudos Retrospectivos , Resultado do Tratamento
12.
Surg Endosc ; 36(3): 2129-2137, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33999252

RESUMO

BACKGROUND: Gastric gastrointestinal stromal tumors (GISTs) exhibit various degrees of aggression and malignant potential. However, no systematic preoperative evaluation strategy to predict the malignancy potential of gastric GISTs has yet been developed. This study aimed to develop a reliable and easy-to-use preoperative risk-scoring model for predicting high malignancy potential (HMP) gastric GISTs. METHODS: The data of 542 patients with pathologically confirmed gastric GISTs who underwent resection were reviewed. Multivariate logistic regression analysis was used to identify significant predictors of HMP. The risk-scoring system (RSS) was based on the predictive factors for HMP, and its performance was validated using a split-sample approach. RESULTS: A total of 239 of 542 (44.1%) surgically resected gastric GISTs had HMP. Multivariate analysis demonstrated that tumor size, location, and surface changes were independent risk factors for HMP. Based on the accordant regression coefficients, the presence of surface ulceration was assigned 1 point. Tumor sizes of 4-6 cm and > 6 cm were assigned 2 and 5 points, respectively. Two points were assigned to cardia or fundus locations. A score of 3 points was the optimal cut-off value for HMP prediction. HMP were found in 19.8% and 82.7% of the low and high-risk groups of the RSS, respectively. The area under the receiver-operating characteristic curve for predicting HMP was 0.81 (95% confidence interval (CI) 0.75-0.86). Discrimination was good after validation (0.75, 95% CI 0.69-0.81). CONCLUSION: This simple RSS could be useful for predicting the malignancy potential of gastric GISTs and may aid preoperative clinical decision making to ensure optimal treatment.


Assuntos
Tumores do Estroma Gastrointestinal , Neoplasias Gástricas , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
13.
Ann Surg Oncol ; 28(1): 106-113, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32591953

RESUMO

BACKGROUND: When non-curative resection is confirmed after endoscopic resection (ER) of early gastric cancer (EGC), delayed surgery is recommended because it provides favorable survival outcomes. Long-term outcome after surgery of EGC with or without previous ER has not been evaluated. OBJECTIVE: The aim of this study was to compare the long-term oncologic safety between primary surgery and delayed surgery after ER. METHODS: Patients who had undergone curative surgery (R0) for EGC were included and were divided into primary and delayed surgery groups. Primary surgery was defined as gastrectomy without ER for EGC, whereas delayed surgery was defined as additional curative gastrectomy due to non-curative resection after ER; an average delay of 21.5 days (range 1-195) was observed. Propensity score matching was performed. The primary outcome was overall survival (OS) and the secondary outcomes were cancer-specific survival (CSS) and disease-free survival (DFS). RESULTS: After propensity score matching, 1439 patients were included, of whom 1042 (72.4%) were in the primary surgery group and 397 (27.6%) were in the delayed surgery group. The OS (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.59-1.27; p = 0.459), CSS (HR 0.47, 95% CI 0.15-1.47; p = 0.196), and DFS (HR 0.54, 95% CI 0.15-1.90; p = 0.334) were not different. CONCLUSIONS: The long-term outcomes of delayed surgery after non-curative ER for EGC were non-inferior to primary surgery. Therefore, an attempt for ER of EGC that satisfies the absolute and expanded indication seems justified for preventing gastrectomy. In case of non-curative resection after ER, additional delayed surgery should be performed.


Assuntos
Gastrectomia , Neoplasias Gástricas , Detecção Precoce de Câncer , Endoscopia , Humanos , Estudos Retrospectivos , Neoplasias Gástricas/cirurgia , Resultado do Tratamento
14.
Opt Express ; 29(23): 37418-37428, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34808813

RESUMO

In this paper, we propose an optofluidic lenticular lens array (OLLA) for a two-dimensional/three-dimensional (2D/3D) switchable display. The OLLA includes a bottom substrate layer with lenticular lens structure, a microfluidic layer with microchannels, and a top substrate layer with inlets as well as outlets. A micro gap is formed between the lenticular lens of the bottom substrate layer and the top substrate layer. When air is in the micro gap, the OLLA behaves as a lenticular lens array, which can realize 3D display. When fluid is filled in the micro gap, because the refractive index of the fluid is the same with the lenticular lens structure, the OLLA equivalents to a transparent flat panel, which can realize a 2D display. Experiments verify that a switchable 2D/3D display prototype based on this OLLA and a smartphone achieves both high-resolution 2D display and high-quality 3D display.

15.
Chemistry ; 27(6): 2065-2071, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-32978969

RESUMO

Organic compounds with selective near-infrared absorption and visible transparency are very desirable for fabrication of transparent/semitransparent optoelectronic devices. Herein, we develop a molecule with selective near-infrared absorption property, QBNA-O, in which four B←N units are incorporated to the core and two benzodioxin groups are introduced at the termini of the dibenzo-azaacene skeleton. QBNA-O exhibits a small optical gap of 1.39 eV due to the strong electron-donating benzodioxin groups and the strong electron-withdrawing B←N units. In toluene solution, QBNA-O shows a strong absorption peak at 856 nm with the full width at half maximum (FWHM) of only 41 nm as well as very weak absorption in the visible range from 380 nm to 760 nm. Thin films of QBNA-O exhibit the average visible transparency (AVT) of 78 % at the thickness of 205 nm and 90 % at the thickness of 45 nm. Solution-processed organic field-effect transistors (OFETs) of QBNA-O display ambipolar transporting behavior with the electron mobility of 0.52 cm2 V-1 s-1 and the hole mobility of 0.013 cm2 V-1 s-1 together with excellent air-stability. The selective NIR absorbing property and excellent charge transporting property imply that QBNA-O can be used to fabricate transparent organic optoelectronic devices.

16.
Chemistry ; 27(13): 4364-4372, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33241609

RESUMO

The B←N unit has a large dipole and it is isoelectronic to C-C moiety with no dipole. Incorporating B←N units into π-conjugated system is a powerful strategy to design organic small molecules and polymers with intriguing opto-electronic properties and excellent opto-electronic device performance. However, it is unclear how the B←N unit affects electronic structures and opto-electronic properties of large π-conjugated molecules. In this work, to address this question, we developed three dibenzo-azaacene molecules in which two B←N units were introduced at different positions. Although the dibenzo-azaacene skeleton is fully π-conjugated, the effect of B←N unit on the electronic structures of the adjacent rings is much stronger than that of the distant rings. As a result, the three molecules with isomerized B←N incorporation patterns possess different electronic structures and exhibit tunable opto-electronic properties. Among the three molecules, the centrosymmetrical molecule exhibits higher LUMO/HOMO energy levels than those of the two axisymmetrical molecules. When used as the active layer in organic field-effect transistors (OFETs), while the two axisymmetrical molecules show unipolar electron transporting property, the centrosymmetrical molecule exhibits ambipolar hole and electron transporting behavior. This work not only deepens our understanding on organoboron π-conjugated molecules, but also indicates a new strategy to tune opto-electronic properties of organic semiconductors for excellent device performance.

17.
Helicobacter ; 26(2): e12783, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33508177

RESUMO

BACKGROUND: Previous studies have suggested a relationship between Helicobacter pylori infection and dyslipidemia; however, large-scale longitudinal studies have not elucidated this association. This study assessed the longitudinal effects of H. pylori infection and eradication on lipid profiles in a large cohort. METHODS: This cohort study included 2,626 adults without dyslipidemia at baseline, who participated in a repeated, regular health-screening examination, which included upper gastrointestinal endoscopy, between January 2009 and December 2018. The primary outcome was incident dyslipidemia at follow-up. RESULTS: During the 10,324 person-years of follow-up, participants with persistent H. pylori infection had a higher incidence rate (130.5 per 1,000 person-years) of dyslipidemia than those whose infections had been successfully controlled (98.1 per 1,000 person-years). In a multivariable model adjusted for age, sex, waist circumference, smoking status, alcohol intake, and education level, the H. pylori eradication group was associated with a lower risk of dyslipidemia than the persistent group (HR, 0.85; 95% CI, 0.77-0.95; p = 0.004). The association persisted after further adjustment for baseline levels of low-density and high-density lipoprotein cholesterol (HR, 0.87; 95% CI, 0.79-0.97; p = 0.014). CONCLUSIONS: H. pylori infection may play a pathophysiologic role in the development of dyslipidemia, whereas H. pylori eradication might decrease the risk of dyslipidemia.


Assuntos
Dislipidemias , Infecções por Helicobacter , Helicobacter pylori , Adulto , Estudos de Coortes , Humanos , Estudos Retrospectivos , Fatores de Risco
18.
J Gastroenterol Hepatol ; 36(3): 657-663, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32656854

RESUMO

BACKGROUND AND AIM: Previous studies suggested an association between Helicobacter pylori infection and osteoporosis; however, large-scale longitudinal studies are lacking to elucidate this association. METHODS: A cohort study of 10 482 women without osteoporosis at baseline who participated in a repeated health-screening examination including an H. pylori-specific immunoglobulin G antibody test was conducted to evaluate the association between H. pylori and osteoporosis development. Osteoporosis was diagnosed using dual-energy X-ray absorptiometry. RESULTS: During the 77 515.3 person-years of follow-up, women with H. pylori infection had a higher rate of incident osteoporosis than those who were uninfected. In a multivariable model adjusted for age, body mass index (BMI), menopausal status, smoking status, regular exercise, comorbidities (including hypertension, diabetes mellitus, dyslipidemia, stroke, or ischemic heart disease), and concomitant medications, the hazard ratio (HR) for incident osteoporosis in women with H. pylori infection compared with that in women without infection was 1.23 (95% confidence interval [CI], 1.03-1.45). The association between H. pylori and osteopenia development was also evident. In the multivariable analysis, menopause (HR, 1.68; 95% CI, 1.31-2.16) and increasing age (HR, 1.07; 95% CI, 1.06-1.08) were identified as significant risk factors for osteoporosis, whereas higher BMI (HR, 0.84; 95% CI, 0.81-0.87) was a protective factor for the risk of osteoporosis. CONCLUSIONS: In this cohort study, H. pylori infection was associated with an increased risk of osteoporosis, independent of risk factors and confounding factors.


Assuntos
Gastrite/complicações , Gastrite/microbiologia , Infecções por Helicobacter , Helicobacter pylori , Osteoporose/epidemiologia , Osteoporose/etiologia , Adulto , Fatores Etários , Anticorpos Antibacterianos/sangue , Biomarcadores/sangue , Feminino , Seguimentos , Gastrite/diagnóstico , Helicobacter pylori/imunologia , Humanos , Incidência , Estudos Longitudinais , Menopausa , Pessoa de Meia-Idade , Osteoporose/diagnóstico , Fatores de Risco
19.
J Gastroenterol Hepatol ; 36(5): 1235-1243, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32886822

RESUMO

BACKGROUND AND AIM: Proton pump inhibitor (PPI)-induced hypochondria can change the composition of the gut microbiota, inducing overgrowth of small bowel bacteria, which has been suggested to promote the development of fatty liver disease through the gut-liver axis. In this study, we aimed to investigate the association between PPI use and the risk of fatty liver disease. METHODS: A retrospective cohort study was conducted using the Korean National Health Insurance Service-National Sample Cohort, a nationwide population-based representative sample, from January 1, 2002, to December 31, 2015. PPI use was identified from treatment claims and considered as a time-varying variable. RESULTS: During 1 463 556 person-years of follow-up, 75 727 patients had at least one PPI prescription, and 3735 patients developed fatty liver disease. The hazard ratio for fatty liver disease comparing PPI users with non-PPI users was 1.68 (95% confidence interval, 1.61-1.75). When adjusted for multiple confounders, including age, sex, body mass index, smoking, alcohol intake, exercise, income level, and comorbidities, the association was still significant (hazard ratio, 1.50; 95% confidence interval, 1.44-1.57). After considering the amounts of PPIs stratified by cumulative defined daily dose, the dose-response effect was observed until 180 days. Subgroup analysis also revealed that PPI use was correlated to an increased risk of fatty liver disease. CONCLUSIONS: This current national wide cohort study suggests that PPI use was associated with an increased risk of fatty liver disease compared with non-use of PPIs. Clinicians should consider fatty liver as a potential risk when prescribing PPI.


Assuntos
Fígado Gorduroso/etiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Intestino Delgado/microbiologia , Inibidores da Bomba de Prótons/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Medicamentos Biossimilares , Relação Dose-Resposta a Droga , Feminino , Humanos , Coreia (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Inibidores da Bomba de Prótons/administração & dosagem , Estudos Retrospectivos , Risco , Adulto Jovem
20.
Dig Surg ; 38(3): 247-254, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33910202

RESUMO

INTRODUCTION: After noncurative endoscopic submucosal dissection (ESD) of superficial esophageal squamous cell carcinoma (SESCC), additional esophagectomy is generally recommended. However, considering its high mortality and morbidity, it is uncertain if additional surgery improves the clinical outcomes. This study aimed to compare the clinical outcomes between patients who were observed without additional treatment and those who underwent radical esophagectomy. METHODS: A total of 52 patients with SESCC who underwent complete but noncurative ESD from January 2008 to December 2016 at the Samsung Medical Center and Asan Medical Center in Korea were retrospectively analyzed. Clinicopathologic characteristics and oncologic outcomes were compared between the observation group (n = 23) and the additional surgery group (n = 29). RESULTS: During a mean follow-up of 34.4 and 41.7 months, respectively, the rates of death (observation vs. surgery, 17.4 vs. 10.3%; p = 0.686), recurrence (observation vs. surgery, 13 vs. 17.2%; p = 1.000), and disease-specific death (observation vs. surgery, 4.3 vs. 6.9%; p = 1.000) did not significantly differ between the 2 groups. The 3-year overall survival was 86.3 and 96.4%, respectively (p = 0.776). The 3-year recurrence-free survival (observation vs. surgery, 85.0 vs. 88.7%; p = 0.960) and disease-specific survival (observation vs. surgery, 95.2 vs. 96.4%; p = 0.564) also did not significantly differ. CONCLUSIONS: The clinical outcomes of close observation of noncuratively resected SESCC are comparable to those of additional surgery, at least in the midterm. The wait-and-see strategy could be a feasible management option after noncurative ESD of SESCC in selected patients.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Esofágicas/cirurgia , Carcinoma de Células Escamosas do Esôfago/cirurgia , Esofagectomia , Cuidados Pós-Operatórios/métodos , Conduta Expectante , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sobrevida , Resultado do Tratamento
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