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Convolutional neural networks (CNNs) provide flexible function approximations for a wide variety of applications when the input variables are in the form of images or spatial data. Although CNNs often outperform traditional statistical models in prediction accuracy, statistical inference, such as estimating the effects of covariates and quantifying the prediction uncertainty, is not trivial due to the highly complicated model structure and overparameterization. To address this challenge, we propose a new Bayesian approach by embedding CNNs within the generalized linear models (GLMs) framework. We use extracted nodes from the last hidden layer of CNN with Monte Carlo (MC) dropout as informative covariates in GLM. This improves accuracy in prediction and regression coefficient inference, allowing for the interpretation of coefficients and uncertainty quantification. By fitting ensemble GLMs across multiple realizations from MC dropout, we can account for uncertainties in extracting the features. We apply our methods to biological and epidemiological problems, which have both high-dimensional correlated inputs and vector covariates. Specifically, we consider malaria incidence data, brain tumor image data, and fMRI data. By extracting information from correlated inputs, the proposed method can provide an interpretable Bayesian analysis. The algorithm can be broadly applicable to image regressions or correlated data analysis by enabling accurate Bayesian inference quickly.
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Teorema de Bayes , Neoplasias Encefálicas , Imagen por Resonancia Magnética , Método de Montecarlo , Redes Neurales de la Computación , Humanos , Modelos Lineales , Imagen por Resonancia Magnética/estadística & datos numéricos , Imagen por Resonancia Magnética/métodos , Malaria/epidemiología , AlgoritmosRESUMEN
Emerging evidence suggests a link between atopic dermatitis (AD) and gastrointestinal disorders, particularly in relation to gut microbial dysbiosis. This study explored the potential exacerbation of AD by gut inflammation and microbial imbalances using an irritable bowel syndrome (IBS) mouse model. Chronic gut inflammation was induced in the model by intrarectal injection of 2,4,6-trinitrobenzene sulfonic acid (TNBS), followed by a 4-week development period. We noted significant upregulation of proinflammatory cytokines in the colon and evident gut microbial dysbiosis in the IBS mice. Additionally, these mice exhibited impaired gut barrier function, increased permeability, and elevated systemic inflammation markers such as IL-6 and LPS. A subsequent MC903 challenge on the right cheek lasting for 7 days revealed more severe AD symptoms in IBS mice compared to controls. Further, fecal microbial transplantation (FMT) from IBS mice resulted in aggravated AD symptoms, a result similarly observed with FMT from an IBS patient. Notably, an increased abundance of Alistipes in the feces of IBS mice correlated with heightened systemic and localized inflammation in both the gut and skin. These findings collectively indicate that chronic gut inflammation and microbial dysbiosis in IBS are critical factors exacerbating AD, highlighting the integral relationship between gut and skin health.
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Dermatitis Atópica , Microbioma Gastrointestinal , Síndrome del Colon Irritable , Humanos , Animales , Ratones , Disbiosis , Microbioma Gastrointestinal/fisiología , Heces , Trasplante de Microbiota Fecal , InflamaciónRESUMEN
Organohalide perovskite materials and related optoelectronic applications have drawn significant attention due to their promising high-performance photon-to-electricity conversion efficiencies. Herein, we demonstrate a highly sensitive self-powered perovskite-based photodetector created with a noise-current-suppressible passivation layer of poly(methyl methacrylate) (PMMA) at the interface between a CH3NH3PbI3 light-absorbing layer and a NiOx hole-transporting layer. Along with the defect passivation effect, the PMMA layer effectively diminishes unwanted carrier recombination losses at the interface, resulting in a significant reduction of the leakage/noise current. Consequently, without external bias, a remarkably high level of specific detectivity (â¼4.5 × 1013 Jones from the dark current and â¼0.81 × 1012 Jones from the noise current) can be achieved due to the use of the PMMA passivation layer, greatly exceeding those of conventional unpassivated perovskite devices. Moreover, we observed a very wide linear dynamic response range of â¼129â dB together with rapid rise and decay response times of â¼52 and â¼18 µs, respectively. Overall, these results provide a solid foundation for advanced interface-engineering to realize high-performance self-powered perovskite photodetectors for various optoelectronic applications.
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Understanding the spatio-temporal patterns of the coronavirus disease 2019 (COVID-19) is essential to construct public health interventions. Spatially referenced data can provide richer opportunities to understand the mechanism of the disease spread compared to the more often encountered aggregated count data. We propose a spatio-temporal Dirichlet process mixture model to analyze confirmed cases of COVID-19 in an urban environment. Our method can detect unobserved cluster centers of the epidemics, and estimate the space-time range of the clusters that are useful to construct a warning system. Furthermore, our model can measure the impact of different types of landmarks in the city, which provides an intuitive explanation of disease spreading sources from different time points. To efficiently capture the temporal dynamics of the disease patterns, we employ a sequential approach that uses the posterior distribution of the parameters for the previous time step as the prior information for the current time step. This approach enables us to incorporate time dependence into our model in a computationally efficient manner without complicating the model structure. We also develop a model assessment by comparing the data with theoretical densities, and outline the goodness-of-fit of our fitted model.
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COVID-19 , Humanos , Teorema de Bayes , COVID-19/epidemiología , Modelos Estadísticos , Método de Montecarlo , Salud Pública , Análisis Espacio-TemporalRESUMEN
In traditional Korean medicine, the 16-herb concoction Bojanggunbi-tang (BGT) is used to treat various gastrointestinal (GI) diseases. In this study, we investigated the regulatory mechanism underlying the influence of BGT on the interstitial cells of Cajal (ICCs), pacemaker cells in the GI tract. Within 12 h of culturing ICCs in the small intestines of mice, the pacemaker potential of ICCs was recorded through an electrophysiological method. An increase in the BGT concentration induced depolarization and decreased firing frequency. This reaction was suppressed by cholinergic receptor muscarinic 3 (CHRM3) antagonists, as well as 5-hydroxytryptamine receptor (5HTR) 3 and 4 antagonists. Nonselective cation channel inhibitors, such as thapsigargin and flufenamic acid, along with protein kinase C (PKC) and mitogen-activated protein kinase (MAPK) inhibitors, also suppressed the BGT reaction. Guanylate cyclase and protein kinase G (PKG) antagonists inhibited BGT, but adenylate cyclase and protein kinase A antagonists had no effect. In conclusion, we demonstrated that BGT acts through CHRM3, 5HTR3, and 5HTR4 to regulate intracellular Ca2+ concentrations and the PKC, MAPK, guanylate cycle, and PKG signaling pathways.
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Células Intersticiales de Cajal , Animales , Ratones , Potenciales de la Membrana , Células Intersticiales de Cajal/metabolismo , Transducción de Señal , Intestino Delgado/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Colinérgicos/metabolismo , Colinérgicos/farmacología , Ratones Endogámicos BALB C , Células CultivadasRESUMEN
PURPOSE: We performed a systematic review and meta-analysis to determine the diagnostic test accuracy of ancillary investigations for declaration of death by neurologic criteria (DNC) in infants and children. SOURCE: We searched MEDLINE, EMBASE, Web of Science, and Cochrane databases from their inception to June 2021 for relevant randomized controlled trials, observational studies, and abstracts published in the last three years. We identified relevant studies using Preferred Reporting Items for Systematic Reviews and Meta-Analysis methodology and a two-stage review. We assessed the risk of bias using the QUADAS-2 tool, and applied Grading of Recommendations Assessment, Development, and Evaluation methodology to determine the certainty of evidence. A fixed-effects model was used to meta-analyze pooled sensitivity and specificity data for each ancillary investigation with at least two studies. PRINCIPAL FINDINGS: Thirty-nine eligible manuscripts assessing 18 unique ancillary investigations (n = 866) were identified. The sensitivity and specificity ranged from 0.00 to 1.00 and 0.50 to 1.00, respectively. The quality of evidence was low to very low for all ancillary investigations, with the exception of radionuclide dynamic flow studies for which it was graded as moderate. Radionuclide scintigraphy using the lipophilic radiopharmaceutical 99mTc-hexamethylpropyleneamine oxime (HMPAO) with or without tomographic imaging were the most accurate ancillary investigations with a combined sensitivity of 0.99 (95% highest density interval [HDI], 0.89 to 1.00) and specificity of 0.97 (95% HDI, 0.65 to 1.00). CONCLUSION: The ancillary investigation for DNC in infants and children with the greatest accuracy appears to be radionuclide scintigraphy using HMPAO with or without tomographic imaging; however, the certainty of the evidence is low. Nonimaging modalities performed at the bedside require further investigation. STUDY REGISTRATION: PROSPERO (CRD42021278788); registered 16 October 2021.
RéSUMé: OBJECTIF: Nous avons réalisé une revue systématique et une méta-analyse pour déterminer la précision des tests diagnostiques des examens auxiliaires pour la déclaration du décès selon des critères neurologiques (DCN) chez les nourrissons et les enfants. SOURCES: Nous avons effectué des recherches dans les bases de données MEDLINE, EMBASE, Web of Science et Cochrane de leur création jusqu'en juin 2021 pour trouver des études randomisées contrôlées, des études observationnelles et des résumés pertinents publiés au cours des trois dernières années. Nous avons identifié les études pertinentes utilisant la méthodologie PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) et une revue en deux étapes. Nous avons évalué le risque de biais en utilisant l'outil QUADAS-2 et appliqué la méthodologie GRADE (Grading of Recommendations Assessment, Development and Evaluation) afin d'évaluer la certitude des données probantes. Un modèle à effets fixes a été utilisé pour méta-analyser les données de sensibilité et de spécificité regroupées pour chaque examen auxiliaire avec au moins deux études. CONSTATATIONS PRINCIPALES: Trente-neuf manuscrits admissibles évaluant 18 examens auxiliaires uniques (n = 866) ont été identifiés. La sensibilité et la spécificité variaient de 0,00 à 1,00 et de 0,50 à 1,00, respectivement. La qualité des données probantes était faible à très faible pour tous les examens auxiliaires, à l'exception des études de circulation nucléaire dynamique, pour lesquelles elle a été classée comme modérée. La scintigraphie nucléaire à l'aide du produit radiopharmaceutique lipophile 99mTc- hexa-méthyl-propylène amine oxime (HMPAO) avec ou sans imagerie tomographique était à la base des examens auxiliaires les plus précis, avec une sensibilité combinée de 0,99 (intervalle de densité le plus élevé [IDE] à 95 %, 0,89 à 1,00) et une spécificité de 0,97 (IDE à 95 %, 0,65 à 1,00). CONCLUSION: L'examen auxiliaire pour un DCN chez les nourrissons et les enfants offrant la plus grande précision semble être la scintigraphie nucléaire utilisant le HMPAO avec ou sans imagerie tomographique; cependant, la certitude des données probantes est faible. Les modalités sans imagerie réalisées au chevet du patient nécessitent un examen plus approfondi. Enregistrement de l'étude: PROSPERO (CRD42021278788); enregistrée le 16 octobre 2021.
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Sesgo , Humanos , Niño , Lactante , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Pancreatic cysts are common. However, most studies are based on data collected from individual centers. The present study aimed to evaluate the changes of management patterns for pancreatic cystic lesions (PCLs) by analyzing large epidemiologic data. METHODS: Between January 2007 and December 2018, information regarding pancreatic cystic lesions was acquired from the nationwide Health Insurance Review and Assessment Service database in Korea. RESULTS: The final number of patients with pancreatic cysts was 165 277 among the total claims for reimbursement of 855 983 associated with PCLs over 12 years. The total number of claims were increased from 19 453 in 2007 to 155 842 in 2018 and the prevalence increased from 0.04% to 0.23%. For 12 years, 2874 (1.7%) had pancreatic cancer and 8212 (5.0%) underwent surgery, and 36 had surgery for twice (total 8248 pancreatectomy). After ruling out claims from the first 3 years of washout period, the incidence increased from 9891 to 24 651 and the crude incidence rate of PCLs expanded from 19.96 per 100 000 to 47.77 per 100 000. Compared to specific neoplasm codes (D136 or D377), the use of pancreatic cyst code (K862) has been remarkably increased and the most common since 2010. The annual number of pancreatectomies increased from 518 to 861 between 2007 and 2012, and decreased to 596 until 2018. The percentage of pancreatic cancer in patients who received pancreatectomy increased from 5.6% in 2007 to 11.7% in 2018. CONCLUSIONS: The incidence of PCLs is rapidly increasing. Among PCLs, indeterminate cyst is increasing outstandingly. A trend of decreasing in the number of resections and increasing cancer rates among resected cysts may be attributed to the updated international guidelines.
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Quiste Pancreático , Neoplasias Pancreáticas , Humanos , Incidencia , Estudios Retrospectivos , Quiste Pancreático/diagnóstico , Quiste Pancreático/epidemiología , Quiste Pancreático/cirugía , Neoplasias Pancreáticas/epidemiología , Neoplasias Pancreáticas/cirugía , Neoplasias Pancreáticas/patología , Neoplasias PancreáticasRESUMEN
The objective of this study is to update the national and regional indoor radon concentrations in South Korea and assess indoor radon exposure. Based on the previously published survey results and the collected measurement data of surveys conducted since 2011, a total of 9271 indoor radon measurement data covering 17 administrative divisions are finally used for analysis. The annual effective dose from the indoor radon exposure is calculated using dose coefficients recommended by the International Commission on Radiological Protection. The population-weighted average indoor radon concentration was estimated to be a geometric mean of 46 Bq m-3(GSD = 1.2) with 3.9% of all samples showing values exceeding 300 Bq m-3. The regional average indoor radon concentration ranged from 34 to 73 Bq m-3. The radon concentrations in detached houses were relatively higher than those in public buildings and multi-family houses. The annual effective doses to the Korean population due to indoor radon exposure were estimated to be 2.18 mSv. The updated values in this study might better represent the national indoor radon exposure level in South Korea because they contain more samples and cover a wider range of geographical areas than previous studies.
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Contaminantes Radiactivos del Aire , Contaminación del Aire Interior , Monitoreo de Radiación , Radón , Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Radón/análisis , República de Corea , ViviendaRESUMEN
BACKGROUND AND AIM: Endoscopic retrograde cholangiopancreatography (ERCP) requires radiation. This study aimed to assess the clinical factors influencing radiation exposure and devise a scoring model for predicting high-dose radiation exposure. METHODS: Endoscopic retrograde cholangiopancreatography cases recorded between 2016 and 2019 in a single tertiary teaching hospital were retrospectively reviewed. A scoring model was created by bootstrap method in a derivation cohort (2016-2018) and was assessed in a validation cohort (2019). RESULTS: Out of 4223 ERCPs, 2983 and 1240 cases were included in the derivation and validation cohorts, respectively. In the derivation cohort, 746 cases (top 25%) comprised the high-dose exposure group, and 2237 cases (bottom 75%) comprised the low-dose exposure group. Nine clinical parameters associated with high-dose exposure were male, pancreatic sphincterotomy, balloon dilatation, biliary or pancreatic drainage, procedures with contrast dye, endoscopist, in-hospital ERCP, and spot image. Stone removal was included by bootstrap analysis. As presented in a nomogram, the weight score of each variable was as follows: male, 1; pancreatic sphincterotomy, 3; balloon dilatation, 7; stone removal, 3; biliary or pancreatic drainage, 5; procedures with contrast dye, 1; endoscopist B, 4; endoscopist C, 5; in-hospital procedure, 3; and spot image, 3. A total score ≥ 15 suggested a high-dose radiation exposure. The sensitivity and specificity of the model for high-dose exposure were 0.562 and 0.813, respectively. In the validation cohort, the model showed reasonable predictability. CONCLUSIONS: Various factors were associated with radiation exposure. The simple scoring system in this study could guide endoscopists in predicting the risk of high-dose radiation exposure.
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Colangiopancreatografia Retrógrada Endoscópica , Exposición a la Radiación , Cateterismo , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Drenaje , Femenino , Humanos , Masculino , Exposición a la Radiación/efectos adversos , Estudios Retrospectivos , Esfinterotomía Endoscópica/métodosRESUMEN
We present the design, fabrication, and testing of a drone-mountable gas sensing platform for environmental monitoring applications. An array of graphene-based field-effect transistors in combination with commercial humidity and temperature sensors are used to relay information by wireless communication about the presence of airborne chemicals. We show that the design, based on an ESP32 microcontroller combined with a 32-bit analog-to-digital converter, can be used to achieve an electronic response similar, within a factor of two, to state-of-the-art laboratory monitoring equipment. The sensing platform is then mounted on a drone to conduct field tests, on the ground and in flight. During these tests, we demonstrate a one order of magnitude reduction in environmental noise by reducing contributions from humidity and temperature fluctuations, which are monitored in real-time with a commercial sensor integrated to the sensing platform. The sensing device is controlled by a mobile application and uses LoRaWAN, a low-power, wide-area networking protocol, for real-time data transmission to the cloud, compatible with Internet of Things (IoT) applications.
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Grafito , Aplicaciones Móviles , Humedad , Monitoreo Fisiológico/métodos , Dispositivos Aéreos No TripuladosRESUMEN
The biological reduction of slow degradation contaminants such as perchlorate (ClO4-) is considered to be a promising water treatment technology. The process is based on the ability of a specific mixed microbial culture to use perchlorate as an electron acceptor in the absence of oxygen. In this study, batch experiments were conducted to investigate the effect of nitrate on perchlorate reduction, the kinetic parameters of the Monod equation and the optimal ratio of acetate to perchlorate for the perchlorate reducing bacterial consortium. The results of this study suggest that acclimated microbial cultures can be applied to treat wastewater containing high concentrations of perchlorate. Reactor experiments were carried out with different hydraulic retention times (HRTs) to determine the optimal operating conditions. A fixed optimal HRT and the effect of nitrate on perchlorate reduction were investigated with various concentrations of the electron donor. The results showed that perchlorate reduction occurred after nitrate removal. Moreover, the presence of sulfate in wastewater had no effect on the perchlorate reduction. However, it had little effect on biomass concentration in the presence of nitrate during exposure to a mixed microbial culture, considering the nitrate as the inhibitor of perchlorate reduction by reducing the degradation rate. The batch scale experiment results illustrated that for efficient operation of perchlorate reduction, the optimal acetate to perchlorate ratio of 1.4:1.0 would be enough. Moreover, these experiments found the following results: the kinetic parameters equivalent to Y = 0.281 mg biomass/mg perchlorate, Ks = 37.619 mg/L and qmax = 0.042 mg perchlorate/mg biomass/h. In addition, anoxic-aerobic experimental reactor results verify the optimal HRT of 6 h for continuous application. Furthermore, it also illustrated that using 600 mg/L of acetate as a carbon source is responsible for 100% of nitrate reduction with less than 50% of the perchlorate reduction, whereas at 1000 mg/L acetate, approximately 100% reduction was recorded.
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Nitratos , Percloratos , Acetatos/farmacología , Reactores Biológicos/microbiología , Carbono , Nitratos/metabolismo , Oxidación-Reducción , Oxígeno , Percloratos/metabolismo , Sulfatos/metabolismo , Aguas Residuales/microbiologíaRESUMEN
A new functional composite was synthesized in this study comprising magnetic-cored dendrimer (MCD) modified with citric acid (CA), succinic acid (SA), and vanillic acid (VA) terminal groups. The CA-MCD, SA-MCD, and VA-MCD exhibited average particle size of 8-18 nm and superparamagnetic behavior. Adsorption potential of the composite was assessed by monitoring methylene blue (MB) removal from contaminated water. The CA-MCD attained adsorption equilibrium in 30 min while SA-MCD and VA-MCD achieved equilibrium in 60 min. The Langmuir model better fitted the adsorption results than the Freundlich model, indicating a monolayer mode of MB adsorption on the composite. Maximum adsorption capacity of CA-MCD, SA-MCD, and VA-MCD was 216.30 mg/g, 184.29 mg/g, and 196.58 mg/g, respectively. The CA-MCD exhibited best adsorption performance by removing 99% MB at pH = 11. In reusability experiments, the CA-MCD, SA-MCD, and VA-MCD maintained over 90% MB adsorption for both 15 mg/L and 50 mg/L solutions in the third cycle. Overall, the organic acid-functionalized MCDs with high adsorption capacity and reusability potential showed utility for practical application for wastewater decontamination.
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Dendrímeros , Contaminantes Químicos del Agua , Azul de Metileno/química , Adsorción , Aguas Residuales/química , Ácido Vanílico , Ácido Succínico , Contaminantes Químicos del Agua/química , Ácido Cítrico/química , Agua , Fenómenos Magnéticos , Cinética , Concentración de Iones de HidrógenoRESUMEN
Adsorptive separation using narrow-micropore adsorbents has demonstrated the potential to separate hydrogen isotopes. In this work, we employed an isotope-responsive separation using cobalt formate. A D2-responsive third sorption step was revealed, and consequently, a noticeable difference was observed in the uptakes of D2 and H2. This may have resulted from the additional space created for D2 due to its dense packing, as DFT calculations revealed that cobalt formate possesses 2.26 kJ/mol higher binding strength for D2 than for H2. The exploitation of this D2-responsive third sorption step renders a promising separation performance, with a D2/H2 selectivity of up to 44 at 25 K/1 bar. Lastly, cobalt formate was synthesized on a gram scale here, which makes it a prospect for commercialization.
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BACKGROUND AND AIM: Functional dyspepsia (FD) is characterized by chronic and unexplained indigestion at upper abdomen. Because of unsatisfactory effect of conventional treatments, demand is growing for complementary and alternative medicine. Rikkunshito (RKT) is a herbal medicine, which has been widely used for FD in Asia; however, the evidence is lacking. We carried out systematic review and meta-analysis to evaluate the effect and safety of RKT in the treatment of FD. METHODS: Electronic databases were searched in April 2019, including PUBMED, EMBASE, and Cochrane Library. All eligible studies should be randomized controlled trials (RCTs) comparing RKT or combination therapy (RKT and western medicine) group to western medicine group. The primary outcome measure was the total clinical efficacy rate (TCE). The secondary outcomes were total dyspepsia symptom scale, gastric emptying rate, gastrin, motilin, recurrence 6 months after treatment, and Hamilton depression rating scale. RESULTS: Fifty-two RCTs with 5475 patients were involved in this systematic review and meta-analysis. Compared with western medicine, RKT showed significant better result, with higher TCE (relative risk = 1.21, 95% confidence interval 1.17 to 1.25, P < 0.001). RKT presented higher reduction of total dyspepsia symptom scale, more improved gastric emptying rate, and lower recurrence 6 months after treatment compared with western medicine. However, there was no significant difference in Hamilton depression rating scale between RKT and western medicine group. Combination therapy brought significant symptom improvement with TCE compared with western medicine alone. CONCLUSIONS: Rikkunshito and combination therapy might be considered an effective alternative treatment for FD. Further rigorously designed and high-quality RCTs are needed.
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Medicamentos Herbarios Chinos/uso terapéutico , Dispepsia/tratamiento farmacológico , Fitoterapia , Quimioterapia Combinada , Dispepsia/etiología , Femenino , Vaciamiento Gástrico , Humanos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Resultado del TratamientoRESUMEN
Bojanggunbi-tang (BGT) is a well-known and widely used herbal prescription in Korea for colon diseases, with well-documented pharmacological effects on the digestive system. The current study aimed to develop a new simple and effective prescription using the original prescription. mBGT, a modified BGT, was developed by mixing the extracts of Lonicera japonica Thunb., Alisma orientalis and Atractylodes macrocephala based on a literature review and screening of 16 kinds of component herbs of BGT. A colitis mouse (Male, BALB/c) model was induced using dextran sulfate sodium (5%). The effects of BGT and mBGT on body weight, histological damage, clinical score, macroscopic score and colon length were compared. The mechanisms of action were analyzed based on cytokine production in colon tissue. mBGT at 300mg/kg showed similar effectiveness to that of BGT on colon shortening (P<0.01), clinical score (P<0.05), macroscopic score (P<0.01) and histological damage (P<0.01). In addition, mBGT decreased cytokines, including Interleukin 1 beta, tumor necrosis factor alpha and Interleukin 17, in a dose-dependent manner. In conclusion, mBGT could be a substitute prescription for BGT in clinics and a candidate for the development of a new BGT-based therapeutic agent against colitis.
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Antiinflamatorios , Colitis , Colon , Medicamentos Herbarios Chinos , Animales , Masculino , Antiinflamatorios/farmacología , Colitis/inducido químicamente , Colitis/metabolismo , Colitis/patología , Colitis/prevención & control , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Citocinas/metabolismo , Sulfato de Dextran , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/farmacología , Mediadores de Inflamación/metabolismo , Ratones Endogámicos BALB CRESUMEN
An isotope-selective responsive system based on molecular recognition in porous materials has potential for the storage and purification of isotopic mixtures but is considered unachievable because of the almost identical physicochemical properties of the isotopes. Herein, a unique isotope-responsive breathing transition of the flexible metal-organic framework (MOF), MIL-53(Al), which can selectively recognize and respond to only D2 molecules through a secondary breathing transition, is reported. This novel phenomenon is examined using in situ neutron diffraction experiments under the same conditions for H2 and D2 sorption experiments. This work can guide the development of a novel isotope-selective recognition system and provide opportunities to fabricate flexible MOF systems for energy-efficient purification of the isotopic mixture.
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STATEMENT OF PROBLEM: The accuracy of 3D printing technology is essential for clinical applications. However, depending on the 3D printing method, machine, and environment, the accuracy varies even if the same computer-aided design (CAD) model is printed. PURPOSE: The purpose of this in vitro study was to evaluate the differences between the CAD model and the printed parts with a simplified guide designed based on the implant guide and to compare the accuracy among 3 types of 3D printers. MATERIAL AND METHODS: A maxilla and mandible implant guide made of complex anatomic structures is difficult to measure accurately. For accurate measurements, 16 simplified guides were designed based on the maxilla and mandible implant guide. The 16 simplified guides were fabricated by using the following 3 different 3D printer technologies: photopolymer jetting (PolyJet), stereolithography apparatus (SLA), and multijet printing (MJP). Each simplified guide was measured 4 times with digital calipers for 20 linear measurements. The measured simplified guides were compared with the CAD model, and the accuracy of the 3D printers was compared. The mean absolute difference and mean relative difference were calculated, and the Bland-Altman analysis was used to evaluate the limits of agreement between the CAD model and the printed parts. The Wilcoxon signed-rank test was performed to evaluate the significant differences among the 3D printers (α=.05). RESULTS: The mean absolute difference and the mean relative difference between the CAD model and the 3D-printed parts were 0.06 ±0.05 mm (0.46 ±0.51%) for PolyJet, 0.09 ±0.05 mm (0.66 ±0.62%) for SLA, and 0.31 ±0.33 mm (1.11 ±0.70%) for MJP. When the 3D printers were compared, significant differences were found between SLA and MJP (P=.006) and between PolyJet and MJP (P=.001). CONCLUSIONS: When the CAD models and the 3D-printed parts of the simplified implant guides were compared, significant accuracy differences were observed. The PolyJet and SLA 3D printers met the required accuracy for clinical applications in dentistry. The most suitable 3D printer, however, should be selected considering all factors.
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Implantes Dentales , Diseño Asistido por Computadora , Maxilar , Impresión Tridimensional , EstereolitografíaRESUMEN
Deuterium has been recognized as an irreplaceable element in industrial and scientific research. However, hydrogen isotope separation still remains a huge challenge due to the identical physicochemical properties of the isotopes. In this paper, a partially fluorinated metal-organic framework (MOF) with copper, a so-called FMOFCu, was investigated to determine the separation efficiency and capacity of the framework for deuterium extraction from a hydrogen isotope mixture. The unique structure of this porous material consists of a trimodal pore system with large tubular cavities connected through a smaller cavity with bottleneck apertures with a size of 3.6 Å plus a third hidden cavity connected by an even smaller aperture of 2.5 Å. Depending on the temperature, these two apertures show a gate-opening effect and the cavities get successively accessible for hydrogen with increasing temperature. Thermal desorption spectroscopy (TDS) measurements indicate that the locally flexible MOF can separate D2 from anisotope mixture efficiently, with a selectivity of 14 at 25 K and 4 at 77 K.
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- The spread of invasive species can have far-reaching environmental and ecological consequences. Understanding invasion spread patterns and the underlying process driving invasions are key to predicting and managing invasions. - We combine a set of statistical methods in a novel way to characterize local spread properties and demonstrate their application using simulated and historical data on invasive insects. Our method uses a Gaussian process fit to the surface of waiting times to invasion in order to characterize the vector field of spread. - Using this method, we estimate with statistical uncertainties the speed and direction of spread at each location. Simulations from a stratified diffusion model verify the accuracy of our method. - We show how we may link local rates of spread to environmental covariates for two case studies: the spread of the gypsy moth ( Lymantria dispar), and hemlock woolly adelgid ( Adelges tsugae) in North America. We provide an R-package that automates the calculations for any spatially referenced waiting time data.
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Distribución Animal , Hemípteros/fisiología , Especies Introducidas , Mariposas Nocturnas/fisiología , Animales , América del NorteRESUMEN
Epimedii Herba (EH) has been used in traditional Asian medicine to treat hemiplegia following stroke. Icariin, its major active component, is used as a quality-control marker and for its various pharmacological effects. We hypothesized that icariin would show protective effects following traumatic brain injury (TBI). The TBI mouse model was induced using a controlled cortical impact method. Body weight, brain damage, motor function, and cognitive function were evaluated. Synaptogenesis markers were analyzed to investigate potential mechanisms of action. The animals were divided into six groups: sham, control, minocycline-treated group, and icariin-treated (3, 10, and 30 mg/kg, p.âo.) groups. The icariin 30 mg/kg-treated group regained body weight at 7 and 8 d post TBI. Icariin 30 mg/kg- and 10 mg/kg-treated groups showed enhanced sensory-motor function at 8 d post TBI in rotarod and balance beam tests. Icariin-treated groups showed increased recognition index in the novel object recognition test at all doses and increased spontaneous alternation in the Y-maze test at 30 mg/kg. Icariin upregulated brain-derived neurotrophic factor, synaptophysin and postsynaptic density protein 95 expressions. However, no protective effects against brain damage or neuronal death were observed. The current results provide a basis for using icariin following TBI and suggest that it could be a candidate for the development of therapeutic agents for functional recovery after TBI.