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1.
Environ Sci Technol ; 58(32): 14237-14248, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39080826

RESUMEN

Methanotrophs are crucial in keeping environmental CH4 emissions in check. However, the contributions of different groups of methanotrophs at terrestrial CH4-oxidation hotspots, such as the oxic-anoxic interface of rice paddies, have shown considerable inconsistency across observations. To address the knowledge gap regarding this inconsistency, methanotrophic microbiomes were enriched from paddy soils in well-mixed CH4-fed batch reactors under six different incubation conditions, prepared as combinations of two CH4 mixing ratios (0.5 and 10%) and three supplemented Cu2+ concentrations (0, 2, and 10 µM). Monitoring of temporal community shifts in these cultures revealed a dominance of Methylocystis spp. in all 0.5%-CH4 cultures, while methanotrophs affiliated to Gammaproteobacteria dominated the 10%-CH4 cultures that were less consistent both temporally and across conditions. The shotgun metagenome analyses of the 0.5%-CH4 cultures corroborated the Methylocystis dominance and, interestingly, showed that copper deficiency did not select for mmoXYZ-possessing methanotrophs. Instead, a mbn cluster, accounting for approximately 5% of the Methylocystis population, was identified, suggesting the ecological significance of methanobactin in Cu-deficient methanotrophy. These findings underscore the important role of Methylocystis spp. in mitigating emissions from terrestrial CH4 hotspots and suggest the feasibility of directed enrichment and/or isolation of Methylocystis spp. for utilization in, for example, methanobactin and polyhydroxybutyrate production.


Asunto(s)
Metano , Methylococcaceae , Methylocystaceae , Metano/metabolismo , Methylococcaceae/metabolismo , Methylocystaceae/metabolismo , Microbiología del Suelo , Microbiota
2.
Nanotechnology ; 34(20)2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36745914

RESUMEN

HfO2-based ferroelectric thin films have attracted significant interest for semiconductor device applications due to their compatibility with complementary metal oxide semiconductor (CMOS) technology. One of the benefits of HfO2-based ferroelectric thin films is their ability to be scaled to thicknesses as low as 10 nm while retaining their ferroelectric properties; a feat that has been difficult to accomplish with conventional perovskite-based ferroelectrics using CMOS-compatible processes. However, reducing the thickness limit of HfO2-based ferroelectric thin films below the sub 5 nm thickness regime while preserving their ferroelectric property remains a formidable challenge. This is because both the structural factors of HfO2, including polymorphism and orientation, and the electrical factors of HfO2-based devices, such as the depolarization field, are known to be highly dependent on the HfO2thickness. Accordingly, when the thickness of HfO2drops below 5 nm, these factors will become even more crucial. In this regard, the size effect of HfO2-based ferroelectric thin films is thoroughly discussed in the present review. The impact of thickness on the ferroelectric property of HfO2-based thin films and the electrical performance of HfO2-based ferroelectric semiconductor devices, such as ferroelectric random-access-memory, ferroelectric field-effect-transistor, and ferroelectric tunnel junction, is extensively discussed from the perspective of fundamental theory and experimental results. Finally, recent developments and reports on achieving ferroelectric HfO2at sub-5 nm thickness regime and their applications are discussed.

3.
Int J Colorectal Dis ; 38(1): 195, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37452913

RESUMEN

PURPOSE: Previously considered a disease of old age, diverticular disease is increasingly prevalent in younger populations. Guidelines on surgical resection have shifted from recommending resection for all young onset patients to an individualized approach. Therefore, we aim to determine demographics and outcomes including radiographic and surgical recurrence rates in patients < 40 years old undergoing resection for diverticular disease. METHODS: A retrospective, single center study was performed. All patients ≤ 39 years undergoing operative intervention for left-sided diverticular disease between Jan 2010 and July 2017 were included. Recurrence was determined by individual review of imaging and operative reports. RESULTS: Overall, 147 (n = 107/72.8% male, mean age = 34.93 ± 4.12 years) patients were included. The majority were ASA 1 or 2 (n = 41/27.9% and n = 82/55.8%). The most common surgical indication was uncomplicated diverticulitis (n = 77, 52.4%) followed by perforation (n = 26/17.7%). The majority (n = 108/73.5%) of cases were elective. Seventy-nine (57.3%) of all cases were performed laparoscopically. Primary anastomosis without diversion was the most common surgical outcome (n = 108/73.5%). Median length of stay was 5 (4, 7) days. There was no mortality. There were three (2.0%) intraoperative and 38 (25.9%) postoperative complications. The most common complication was anastomotic leak (n = 6/4.1%). The majority (n = 5) of leaks occurred after elective surgery. Two neoplastic lesions (1.3% of cohort) were found (1 adenoma with low-grade dysplasia/1 polyp cancer). Over a mean follow-up of 96 (74, 123) months, only 2 (1.3%) patients experienced a surgical or radiological recurrence. CONCLUSION: Both neoplasia and recurrence after resection for diverticular disease in young onset patients are rare. Leaks after primary anastomosis even in the elective setting warrant careful consideration of a defunctioning ileostomy.


Asunto(s)
Diverticulitis del Colon , Diverticulitis , Humanos , Masculino , Adulto , Femenino , Estudios Retrospectivos , Diverticulitis/cirugía , Colectomía/métodos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Procedimientos Quirúrgicos Electivos/efectos adversos , Diverticulitis del Colon/cirugía , Diverticulitis del Colon/complicaciones , Resultado del Tratamiento
4.
Colorectal Dis ; 25(9): 1896-1909, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37563772

RESUMEN

AIM: Intersphincteric resection (ISR) is an oncologically complex operation for very low-lying rectal cancers. Yet, definition, anatomical description, operative indications and operative approaches to ISR are not standardized. The aim of this study was to standardize the definition of ISR by reaching international consensus from the experts in the field. This standardization will allow meaningful comparison in the literature in the future. METHOD: A modified Delphi approach with three rounds of questionnaire was adopted. A total of 29 international experts from 11 countries were recruited for this study. Six domains with a total of 37 statements were examined, including anatomical definition; definition of intersphincteric dissection, intersphincteric resection (ISR) and ultra-low anterior resection (uLAR); indication for ISR; surgical technique of ISR; specimen description of ISR; and functional outcome assessment protocol. RESULTS: Three rounds of questionnaire were performed (response rate 100%, 89.6%, 89.6%). Agreement (≥80%) reached standardization on 36 statements. CONCLUSION: This study provides an international expert consensus-based definition and standardization of ISR. This is the first study standardizing terminology and definition of deep pelvis/anal canal anatomy from a surgical point of view. Intersphincteric dissection, ISR and uLAR were specifically defined for precise surgical description. Indication for ISR was determined by the rectal tumour's maximal radial infiltration (T stage) below the levator ani. A new surgical definition of T3isp was reached by consensus to define T3 low rectal tumours infiltrating the intersphincteric plane. A practical flowchart for surgical indication for uLAR/ISR/abdominoperineal resection was developed. A standardized ISR surgical technique and functional outcome assessment protocol was defined.


Asunto(s)
Neoplasias del Recto , Recto , Humanos , Consenso , Técnica Delphi , Recto/patología , Canal Anal , Neoplasias del Recto/patología , Diafragma Pélvico , Resultado del Tratamiento
5.
Sensors (Basel) ; 23(5)2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36904807

RESUMEN

A static modulated Fourier transform spectrometer has been noted to be a compact and fast evaluation tool for spectroscopic inspection, and many novel structures have been reported to support its performance. However, it still suffers from poor spectral resolution due to the limited sampling data points, which marks its intrinsic drawback. In this paper, we outline the enhanced performance of a static modulated Fourier transform spectrometer with a spectral reconstruction method that can compensate for the insufficient data points. An enhanced spectrum can be reconstructed by applying a linear regression method to a measured interferogram. We obtain the transfer function of a spectrometer by analyzing what interferogram can be detected with different values of parameters such as focal length of the Fourier lens, mirror displacement, and wavenumber range, instead of direct measurement of the transfer function. Additionally, the optimal experimental conditions for the narrowest spectral width are investigated. Application of the spectral reconstruction method achieves an improved spectral resolution from 74 cm-1 when spectral reconstruction is not applied to 8.9 cm-1, and a narrowed spectral width from 414 cm-1 to 371 cm-1, which are close to the values of the spectral reference. In conclusion, the spectral reconstruction method in a compact static modulated Fourier transform spectrometer effectively enhances its performance without any additional optic in the structure.

6.
Anal Chem ; 94(50): 17448-17455, 2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36480911

RESUMEN

The outbreak of the novel coronavirus disease 2019 (COVID-19) pandemic induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused millions of fatalities all over the world. Unquestionably, the effective and timely testing for infected individuals is the most imperative for the prevention of the ongoing pandemic. Herein, a new method was established for detecting SARS-CoV-2 based on the self-priming hairpin-utilized isothermal amplification of the G-rich sequence (SHIAG). In this strategy, the target RNA binding to the hairpin probe (HP) was uniquely devised to lead to the self-priming-mediated extension followed by the continuously repeated nicking and extension reactions, consequently generating abundant G-rich sequences from the intended reaction capable of producing fluorescence signals upon specifically interacting with thioflavin T (ThT). Based on the unique isothermal design concept, we successfully identified SARS-CoV-2 genomic RNA (gRNA) as low as 0.19 fM with excellent selectivity by applying only a single HP and further verified its practical diagnostic capability by reliably testing a total of 100 clinical specimens for COVID-19 with 100% clinical sensitivity and specificity. This study would provide notable insights into the design and evolution of new isothermal strategies for the sensitive and facile detection of SARS-CoV-2 under resource constraints.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Sensibilidad y Especificidad , ARN Viral/genética
7.
Int J Colorectal Dis ; 37(8): 1885-1891, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35869990

RESUMEN

PURPOSE: Laparoscopic surgery for complicated Crohn's (CD) is often technically challenging. Previous studies are limited by the comparison of heterogeneous cohorts of patients undergoing laparoscopic vs open surgery. We aimed to compare perioperative and long-term outcomes of matched patients undergoing laparoscopic and open colonic and ileocolonic resection. Primary outcomes were operative time, blood loss, and complications. Long-term outcomes were subsequent intraabdominal CD surgery, incisional hernia repair, and stoma reversal rates. METHODS: Laparoscopic and open CD patients were 1:1 propensity score matched on age, body mass index, sex, indication, ASA grade, prior abdominal surgery, and postoperative Crohn's medication use based on the laparoscopic approach. RESULTS: A total of 906 patients underwent surgery for complex CD. After propensity matching, 386 were analyzed (193 open/193 lap, 51.3% male, mean age 33.9 + / - 12.6). Mean follow-up was 9.8 (range 7.9-12.1) years. Length of stay [(LOS) 6 (4, 8) vs 8 (5, 11) days, p < 0.001] and operative time [154 (110, 216) vs 176 (126, 239) min, p = 0.03] were shorter in the laparoscopic group. There was no difference in other complications or mortality. After adjusting for postoperative medications, no association was found between operative approach and subsequent intra-abdominal operation or incisional hernia repair. Laparoscopic patients were less likely to have postoperative sepsis [OR 0.40 (0.18, 0.91), p = 0.03]. CONCLUSION: In the setting of complicated Crohn's, in matched cohorts, laparoscopic surgery is associated with reduced operative times and LOS. Mortality, reoperation, and symptomatic hernia rates were equivalent to open surgery. Patients undergoing laparoscopic surgery are less likely to experience postoperative sepsis.


Asunto(s)
Enfermedad de Crohn , Hernia Incisional , Laparoscopía , Sepsis , Adulto , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/cirugía , Femenino , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Reoperación , Estudios Retrospectivos , Sepsis/cirugía , Resultado del Tratamiento , Adulto Joven
8.
Macromol Rapid Commun ; 43(20): e2200401, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35836310

RESUMEN

Inspired by many living creatures with adjustment of shape and color in an ever-changing environment, color changeable shape memory hydrogels are designed and expected to be potential candidates in the fields spanning from anti-counterfeiting to biomedical devices. However, they normally require complex synthesis, and more importantly, the cooling-induced shape recovery hydrogel is still rare and in its infancy so far. Herein, a unique color changeable shape memory hydrogel by simply incorporating polyvinylalcohol and copper acetate into covalent polyacrylamide network is developed. As core functional element, copper ions serve as reversible crosslinks after heating to achieve excellent cooling-triggered shape memory effect, color shifting and self-healing behavior, showing significant potential in diverse applications like grabbing, information encryption, and biomimetic designs. This work may guide the development of cooling-triggered smart hydrogels for practical applications.


Asunto(s)
Hidrogeles , Alcohol Polivinílico , Cobre , Iones , Acetatos
9.
Sensors (Basel) ; 22(15)2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-35957371

RESUMEN

Based on the fact that cogwheels are indispensable parts in manufacturing, we present the acoustic resonance testing (ART) of small data on sintered cogwheels for quality control in the context of non-destructive testing (NDT). Considering the lack of extensive studies on cogwheel data by means of ART in combination with machine learning (ML), we utilize time-frequency domain feature analysis and apply ML algorithms to the obtained feature sets in order to detect damaged samples in two ways: one-class and binary classification. In each case, despite small data, our approach delivers robust performance: All damaged test samples reflecting real-world scenarios are recognized in two one-class classifiers (also called detectors), and one intact test sample is misclassified in binary ones. This shows the usefulness of ML and time-frequency domain feature analysis in ART on a sintered cogwheel dataset.


Asunto(s)
Algoritmos , Aprendizaje Automático , Acústica
10.
Sensors (Basel) ; 22(19)2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36236526

RESUMEN

The goal of gaze estimation is to estimate a gaze vector from an image containing a face or eye(s). Most existing studies use pre-defined fixed-resolution images to estimate the gaze vector. However, images captured from in-the-wild environments may have various resolutions, and variation in resolution can degrade gaze estimation performance. To address this problem, a gaze estimation method from arbitrary-sized low-resolution images is proposed. The basic idea of the proposed method is to combine knowledge distillation and feature adaptation. Knowledge distillation helps the gaze estimator for arbitrary-sized images generate a feature map similar to that from a high-resolution image. Feature adaptation makes creating a feature map adaptive to various resolutions of an input image possible by using a low-resolution image and its scale information together. It is shown that combining these two ideas improves gaze estimation performance substantially in the ablation study. It is also demonstrated that the proposed method can be generalized to other popularly used gaze estimation models through experiments using various backbones.

11.
Sensors (Basel) ; 22(20)2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36298324

RESUMEN

Although the performance of 3D human pose and shape estimation methods has improved considerably in recent years, existing approaches typically generate 3D poses defined in a camera or human-centered coordinate system. This makes it difficult to estimate a person's pure pose and motion in a world coordinate system for a video captured using a moving camera. To address this issue, this paper presents a camera motion agnostic approach for predicting 3D human pose and mesh defined in the world coordinate system. The core idea of the proposed approach is to estimate the difference between two adjacent global poses (i.e., global motion) that is invariant to selecting the coordinate system, instead of the global pose coupled to the camera motion. To this end, we propose a network based on bidirectional gated recurrent units (GRUs) that predicts the global motion sequence from the local pose sequence consisting of relative rotations of joints called global motion regressor (GMR). We use 3DPW and synthetic datasets, which are constructed in a moving-camera environment, for evaluation. We conduct extensive experiments and prove the effectiveness of the proposed method empirically.


Asunto(s)
Algoritmos , Humanos , Movimiento (Física)
12.
Appl Environ Microbiol ; 87(5): e0230120, 2021 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-33355098

RESUMEN

Unique means of copper scavenging have been identified in proteobacterial methanotrophs, particularly the use of methanobactin, a novel ribosomally synthesized, post-translationally modified polypeptide that binds copper with very high affinity. The possibility that copper sequestration strategies of methanotrophs may interfere with copper uptake of denitrifiers in situ and thereby enhance N2O emissions was examined using a suite of laboratory experiments performed with rice paddy microbial consortia. Addition of purified methanobactin from Methylosinus trichosporium OB3b to denitrifying rice paddy soil microbial consortia resulted in substantially increased N2O production, with more pronounced responses observed for soils with lower copper content. The N2O emission-enhancing effect of the soil's native mbnA-expressing Methylocystaceae methanotrophs on the native denitrifiers was then experimentally verified with a Methylocystaceae-dominant chemostat culture prepared from a rice paddy microbial consortium as the inoculum. Finally, with microcosms amended with various cell numbers of methanobactin-producing Methylosinus trichosporium OB3b before CH4 enrichment, microbiomes with different ratios of methanobactin-producing Methylocystaceae to gammaproteobacterial methanotrophs incapable of methanobactin production were simulated. Significant enhancement of N2O production from denitrification was evident in both Methylocystaceae-dominant and Methylococcaceae-dominant enrichments, albeit to a greater extent in the former, signifying the comparative potency of methanobactin-mediated copper sequestration, while implying the presence of alternative copper abstraction mechanisms for Methylococcaceae. These observations support that copper-mediated methanotrophic enhancement of N2O production from denitrification is plausible where methanotrophs and denitrifiers cohabit. IMPORTANCE Proteobacterial methanotrophs-groups of microorganisms that utilize methane as a source of energy and carbon-have been known to employ unique mechanisms to scavenge copper, namely, utilization of methanobactin, a polypeptide that binds copper with high affinity and specificity. Previously the possibility that copper sequestration by methanotrophs may lead to alteration of cuproenzyme-mediated reactions in denitrifiers and consequently increase emission of potent greenhouse gas N2O has been suggested in axenic and coculture experiments. Here, a suite of experiments with rice paddy soil slurry cultures with complex microbial compositions were performed to corroborate that such copper-mediated interplay may actually take place in environments cohabited by diverse methanotrophs and denitrifiers. As spatial and temporal heterogeneity allows for spatial coexistence of methanotrophy (aerobic) and denitrification (anaerobic) in soils, the results from this study suggest that this previously unidentified mechanism of N2O production may account for a significant proportion of N2O efflux from agricultural soils.


Asunto(s)
Cobre/metabolismo , Imidazoles/metabolismo , Consorcios Microbianos , Óxido Nitroso , Oligopéptidos/metabolismo , Proteobacteria/metabolismo , Óxido Nitroso/metabolismo , Suelo/química , Microbiología del Suelo
13.
FASEB J ; 34(6): 7427-7441, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32378256

RESUMEN

8-Oxoguanine DNA glycosylase1 (OGG1)-initiated base excision repair (BER) is the primary pathway to remove the pre-mutagenic 8-oxo-7,8-dihydroguanine (8-oxoG) from DNA. Recent studies documented 8-oxoG serves as an epigenetic-like mark and OGG1 modulates gene expression in oxidatively stressed cells. For this new role of OGG1, two distinct mechanisms have been proposed: one is coupled to base excision, while the other only requires substrate binding of OGG1--both resulting in conformational adjustment in the adjacent DNA sequences providing access for transcription factors to their cis-elements. The present study aimed to examine if BER activity of OGG1 is required for pro-inflammatory gene expression. To this end, Ogg1/OGG1 knockout/depleted cells were transfected with constructs expressing wild-type (wt) and repair-deficient mutants of OGG1. OGG1's promoter enrichment, oxidative state, and gene expression were examined. Results showed that TNFα exposure increased levels of oxidatively modified cysteine(s) of wt OGG1 without impairing its association with promoter and facilitated gene expression. The excision deficient K249Q mutant was even a more potent activator of gene expression; whereas, mutant OGG1 with impaired substrate recognition/binding was not. These data suggested the interaction of OGG1 with its substrate at regulatory regions followed by conformational adjustment in the adjacent DNA is the primary mode to modulate inflammatory gene expression.


Asunto(s)
ADN Glicosilasas/metabolismo , Reparación del ADN/fisiología , Proteínas de Unión al ADN/metabolismo , ADN/metabolismo , Transcripción Genética/fisiología , Línea Celular , Daño del ADN/fisiología , Guanina/análogos & derivados , Guanina/metabolismo , Células HEK293 , Humanos , Estrés Oxidativo/fisiología , Transducción de Señal/fisiología , Factores de Transcripción/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
14.
BMC Geriatr ; 21(1): 359, 2021 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-34118884

RESUMEN

BACKGROUND: Evidence regarding the association between daily steps recommendation and older adults' lower limb strength is lacking; thus, this study investigated whether taking at least 7,000 steps/day is cross-sectionally and prospectively related to lower-extremity performance in older Taiwanese adults. METHODS: There were 89 community-dwelling adults aged over 60 years (mean age: 69.5 years) attending both baseline and follow-up surveys. This study used adjusted logistic regression analysis to explore cross-sectional and prospective relationships between their accelerometer-assessed daily steps and lower-extremity performance (five-times-sit-to-stand test). RESULTS: This study found the older adults who took 7,000 steps/day were more likely to have better lower-extremity performance cross-sectionally (odds ratio [OR] = 3.82; 95 % confidence interval [CI]: 1.04, 13.95; p = 0.04), as well as to maintain or increase their lower-extremity performance prospectively (OR = 3.53; 95 % CI: 1.05, 11.84; p = 0.04). CONCLUSIONS: Our findings support a minimum recommended level of step-based physical activity for older adults, namely, 7,000 steps/day, as beneficial for maintaining or increasing older adults' lower-extremity performance.


Asunto(s)
Ejercicio Físico , Extremidad Inferior , Anciano , Estudios Transversales , Humanos , Vida Independiente , Estudios Prospectivos , Caminata
15.
Nucleic Acids Res ; 47(22): 11527-11537, 2019 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-31733056

RESUMEN

DNA methyltransferases (DNMTs) are enzymes responsible for establishing and maintaining DNA methylation in cells. DNMT inhibition is actively pursued in cancer treatment, dominantly through the formation of irreversible covalent complexes between small molecular compounds and DNMTs that suffers from low efficacy and high cytotoxicity, as well as no selectivity towards different DNMTs. Herein, we discover aptamers against the maintenance DNA methyltransferase, DNMT1, by coupling Asymmetrical Flow Field-Flow Fractionation (AF4) with Systematic Evolution of Ligands by EXponential enrichment (SELEX). One of the identified aptamers, Apt. #9, contains a stem-loop structure, and can displace the hemi-methylated DNA duplex, the native substrate of DNMT1, off the protein on sub-micromolar scale, leading for effective enzymatic inhibition. Apt. #9 shows no inhibition nor binding activity towards two de novo DNMTs, DNMT3A and DNMT3B. Intriguingly, it can enter cancer cells with over-expression of DNMT1, colocalize with DNMT1 inside the nuclei, and inhibit the activity of DNMT1 in cells. This study opens the possibility of exploring the aptameric DNMT inhibitors being a new cancer therapeutic approach, by modulating DNMT activity selectively through reversible interaction. The aptamers could also be valuable tools for study of the functions of DNMTs and the related epigenetic mechanisms.


Asunto(s)
Aptámeros de Nucleótidos/química , ADN (Citosina-5-)-Metiltransferasa 1/antagonistas & inhibidores , Metilación de ADN/genética , Neoplasias/genética , Aptámeros de Nucleótidos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/análisis , Epigénesis Genética/genética , Células HEK293 , Células HeLa , Humanos , Neoplasias/tratamiento farmacológico
16.
J Card Surg ; 36(8): 2767-2773, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33993525

RESUMEN

OBJECTIVE: Takotsubo syndrome following cardiac surgery is a rare occurrence. However, early diagnosis is essential to prevent treatment which could increase the left ventricular outflow tract pressure gradient in patients with Takotsubo syndrome, and lead to cardiogenic shock. Therefore, our study aimed to identify the incidence of Takotsubo syndrome after cardiopulmonary bypass and the associated risk factors and prognosis. METHODS: We retrospectively studied 5773 patients who underwent cardiopulmonary bypass between February 2007 and July 2017. Among these, Takotsubo syndrome was diagnosed in 52 (0.9%). To evaluate the risk factors for Takotsubo syndrome, 104 of the remaining 5721 patient were randomly selected as the control group (1:2 ratio). Univariate and multivariate logistic regression analyses were used for risk factor analysis. RESULTS: Majority of patients (69.2%) in the Takotsubo syndrome group underwent mitral valve surgery, compared with 32.7% in the control group. The following risk factors of Takotsubo syndrome were identified: atrio-ventricular valve surgery (odds ratio (OR) 10.5; 95% confidence interval (CI), 2.6-42.5; p = 0.001); and the immediate postoperative use of epinephrine (OR, 3.3; 95% CI, 1.0-10.7; p = 0.05) and dobutamine (OR, 4.8; 95% CI, 1.72-13.3; p = 0.003). Hypertension was a significant protective factor against Takotsubo syndrome following cardiac surgery (OR, 0.22; 95% CI, 0.06-0.73; p = 0.01). CONCLUSION: Takotsubo syndrome following cardiac surgery is rare. Immediate postoperative use of epinephrine and doputamine, as well as atrio-ventricular valve surgery were factors associated with the development of Takotsubo syndrome.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Cardiomiopatía de Takotsubo , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Estudios de Casos y Controles , Humanos , Estudios Retrospectivos , Factores de Riesgo , Cardiomiopatía de Takotsubo/epidemiología , Cardiomiopatía de Takotsubo/etiología
17.
Sensors (Basel) ; 21(13)2021 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-34283128

RESUMEN

Three-dimensional human mesh reconstruction from a single video has made much progress in recent years due to the advances in deep learning. However, previous methods still often reconstruct temporally noisy pose and mesh sequences given in-the-wild video data. To address this problem, we propose a human pose refinement network (HPR-Net) based on a non-local attention mechanism. The pipeline of the proposed framework consists of a weight-regression module, a weighted-averaging module, and a skinned multi-person linear (SMPL) module. First, the weight-regression module creates pose affinity weights from a 3D human pose sequence represented in a unit quaternion form. Next, the weighted-averaging module generates a refined 3D pose sequence by performing temporal weighted averaging using the generated affinity weights. Finally, the refined pose sequence is converted into a human mesh sequence using the SMPL module. HPR-Net is a simple but effective post-processing network that can substantially improve the accuracy and temporal smoothness of 3D human mesh sequences obtained from an input video by existing human mesh reconstruction methods. Our experiments show that the noisy results of the existing methods are consistently improved using the proposed method on various real datasets. Notably, our proposed method reduces the pose and acceleration errors of VIBE, the existing state-of-the-art human mesh reconstruction method, by 1.4% and 66.5%, respectively, on the 3DPW dataset.

18.
Molecules ; 26(11)2021 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-34072968

RESUMEN

We discuss the data sampling frequency, the spectral resolution, and the limit for non-aliasing in the static modulated Fourier transform spectrometer based on a modified Sagnac interferometer. The measurement was performed in a very short 4 ms, which is applicable for real time field operation. The improved spectrometer characteristics were used to investigate the spectral properties of an InGaAs light emitting diode. In addition, The measured spectral peak was shifted from 6420 cm-1 to 6365 cm-1, as the temperature increased from 25 °C to 40 °C, when the operating current is fixed to be 0.55 A. As the applied current increased from 0.30 A to 0.55 A at room temperature, the spectral width was broadened from 316 cm-1 to 384 cm-1. Compared to the conventional Fourier transform spectrometer, the measured spectral width by the static modulated Fourier transform spectrometer showed a deviation less than 10%, and the spectral peak shift according to the temperature rise showed a difference within 2%.

19.
Molecules ; 26(19)2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34641599

RESUMEN

In this paper, a simple and powerful method to control the induced handedness of helical nanofilaments (HNFs) is presented. The nanofilaments are formed by achiral bent-core liquid crystal molecules employing a cholesteric liquid crystal field obtained by doping a rod-like nematogen with a chiral dopant. Homochiral helical nanofilaments are formed in the nanophase-separated helical nanofilament/cholesteric phase from a mixture with a cholesteric phase. This cholesteric phase forms at a temperature higher than the temperature at which the helical nanofilament in a bent-core molecule appears. Under such conditions, the cholesteric liquid crystal field acts as a driving force in the nucleation of HNFs, realizing a perfectly homochiral domain consisting of identical helical nanofilament handedness.

20.
Zhongguo Zhong Yao Za Zhi ; 46(7): 1696-1700, 2021 Apr.
Artículo en Zh | MEDLINE | ID: mdl-33982471

RESUMEN

At present, the issues regarding multi-center clinical trials of new drugs of traditional Chinese medicine(TCM) remain: the lack of agreement on the content and scope of the ethical review among the ethics committee members of the center and the participating units results in repeated review, which leads to a time-consuming ethical review process. Moreover, the review capabilities of the ethics committees of various research centers are uneven, which is not necessarily beneficial to the protection of subjects' rights and safety. In view of the existing problems, to improve the efficiency of ethical review of multi-center clinical trials of new drugs of TCM and avoid repeated reviews, the TCM Clinical Evaluation Professional Committee of Chinese Pharmaceutical Association organized experts to formulate the "Consensus on collaborative ethical review of multi-center clinical trials of new drugs of TCM(version 1.0)"(hereinafter referred to as "Consensus"). The "Consensus" is formulated in accordance with the requirements of relevant documents such as but not limited to "the opinions on deepening the reform of the evaluation and approval system to encourage the innovation of pharmaceutical medical devices", "the regulations of ethical review of biomedical research involving human subjects". The "Consensus" covers the scope of application, formulation principles, conditions for the ethics committee of the center, sharing of ethical review resources, scope and procedure of collaborative review, rights and obligations, etc. The aims of the "Consensus" is to preliminarily explore and establish a scientific and operable ethical review procedure. Additionally, on the basis of fully protecting the rights and interests of the subjects, a collaborative ethical review agreement needs to be signed to clarify the ethical review responsibilities of all parties, to avoid repeated review, and to improve the efficiency and quality of ethical review in multi-center clinical trials of new drugs of TCM.


Asunto(s)
Investigación Biomédica , Medicamentos Herbarios Chinos , Preparaciones Farmacéuticas , Ensayos Clínicos como Asunto , Consenso , Revisión Ética , Humanos , Medicina Tradicional China , Estudios Multicéntricos como Asunto
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