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1.
Opt Express ; 32(5): 7197-7206, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38439407

RESUMEN

In this work, we demonstrate photonic fabrication by integrating waveguide resonators and groove structures using cost-effective i-line stepper lithography on a 6-inch full wafer. Low-loss silicon nitride (SiN) waveguide can be realized with the quality (Q) factor of waveguide resonators up to 105. In addition, groove structures are also integrated by the full-wafer process, providing long-term stability of coupling and package solutions. The uniformity of different die locations is verified within the full wafer, showing the good quality of the fabricated photonic devices. This process integration of photonic devices provides the potential for mass-productive, high-yield, and high-uniformity manufacturing.

2.
Surg Endosc ; 37(9): 6834-6843, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37308764

RESUMEN

BACKGROUND: The major treatment for perforated peptic ulcers (PPU) is surgery. It remains unclear which patient may not get benefit from surgery due to comorbidity. This study aimed to generate a scoring system by predicting mortality for patients with PPU who received non-operative management (NOM) and surgical treatment. METHOD: We extracted the admission data of adult (≥ 18 years) patients with PPU disease from the NHIRD database. We randomly divided patients into 80% model derivation and 20% validation cohorts. Multivariate analysis with a logistic regression model was applied to generate the scoring system, PPUMS. We then apply the scoring system to the validation group. RESULT: The PPUMS score ranged from 0 to 8 points, composite with age (< 45: 0 points, 45-65: 1 point, 65-80: 2 points, > 80: 3 points), and five comorbidities (congestive heart failure, severe liver disease, renal disease, history of malignancy, and obesity: 1 point each). The areas under ROC curve were 0.785 and 0.787 in the derivation and validation groups. The in-hospital mortality rates in the derivation group were 0.6% (0 points), 3.4% (1 point), 9.0% (2 points), 19.0% (3 points), 30.2% (4 points), and 45.9% when PPUMS > 4 point. Patients with PPUMS > 4 had a similar in-hospital mortality risk between the surgery group [laparotomy: odds ratio (OR) = 0.729, p = 0.320, laparoscopy: OR = 0.772, p = 0.697] and the non-surgery group. We identified similar results in the validation group. CONCLUSION: PPUMS scoring system effectively predicts in-hospital mortality for perforated peptic ulcer patients. It factors in age and specific comorbidities is highly predictive and well-calibrated with a reliable AUC of 0.785-0.787. Surgery, no matter laparotomy or laparoscope, significantly reduced mortality for scores < = 4. However, patients with a score > 4 did not show this difference, calling for tailored approaches to treatment based on risk assessment. Further prospective validation is suggested.


Asunto(s)
Laparoscopía , Úlcera Péptica Perforada , Adulto , Humanos , Resultado del Tratamiento , Mortalidad Hospitalaria , Medición de Riesgo , Laparoscopía/métodos , Úlcera Péptica Perforada/etiología , Estudios Retrospectivos
3.
Anticancer Res ; 43(5): 1933-1941, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37097665

RESUMEN

BACKGROUND/AIM: Colorectal cancer (CRC) is one of the most common malignancies and cause of cancer-related deaths worldwide. The combination of chemotherapeutics working with different mechanisms enhances the therapeutic effects and delays the development of resistance. This study investigated the anticancer effect of the combination of ribociclib (LEE011) and irinotecan (SN38) on CRC cells. MATERIALS AND METHODS: HT-29 and SW480 cells were treated with LEE011, SN38, or the combination of LEE011 and SN38. Cell viability and cell cycle distribution were analyzed. The expression of cell cycle- and apoptosis-related proteins was determined using western blot. RESULTS: The combination of LEE011 and SN38 elicited a synergistic antiproliferative effect on HT-29 (PIK3CAP449T mutation) cells, and an antagonistic antiproliferative effect on SW480 (KRASG12V mutation) cells. LEE011 inhibited retinoblastoma protein (Rb) phosphorylation and led to G1 arrest in HT-29 and SW480 cells. SN38 treatment caused a significant increase in the phosphorylation levels of Rb, cyclin B1, and CDC2 in SW480 cells and induced S phase arrest. Furthermore, SN38 treatment increased the phosphorylation levels of p53 and activated caspase-3 and caspase-8 in HT-29 and SW480 cells. LEE011-induced G1 arrest contributed to its synergistic antiproliferative effect with SN38 in HT-29 cells through the down-regulation of the phosphorylation of Rb. In addition, it elicited an antagonistic effect with SN38 in SW480 cells by changing the phosphorylation levels of Rb and activating caspase-8. CONCLUSION: The effects of the combination of LEE011 and conventional chemotherapy drugs on CRC depend on the chemotherapy drug and the specific gene mutation harbored by tumor cells.


Asunto(s)
Neoplasias Colorrectales , Humanos , Irinotecán/farmacología , Caspasa 8 , Proliferación Celular , Línea Celular Tumoral , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Camptotecina/farmacología , Apoptosis
4.
Sensors (Basel) ; 21(24)2021 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-34960388

RESUMEN

This paper presents a wearable device, fitted on the waist of a participant that recognizes six activities of daily living (walking, walking upstairs, walking downstairs, sitting, standing, and laying) through a deep-learning algorithm, human activity recognition (HAR). The wearable device comprises a single-board computer (SBC) and six-axis sensors. The deep-learning algorithm employs three parallel convolutional neural networks for local feature extraction and for subsequent concatenation to establish feature fusion models of varying kernel size. By using kernels of different sizes, relevant local features of varying lengths were identified, thereby increasing the accuracy of human activity recognition. Regarding experimental data, the database of University of California, Irvine (UCI) and self-recorded data were used separately. The self-recorded data were obtained by having 21 participants wear the device on their waist and perform six common activities in the laboratory. These data were used to verify the proposed deep-learning algorithm on the performance of the wearable device. The accuracy of these six activities in the UCI dataset and in the self-recorded data were 97.49% and 96.27%, respectively. The accuracies in tenfold cross-validation were 99.56% and 97.46%, respectively. The experimental results have successfully verified the proposed convolutional neural network (CNN) architecture, which can be used in rehabilitation assessment for people unable to exercise vigorously.


Asunto(s)
Aprendizaje Profundo , Dispositivos Electrónicos Vestibles , Actividades Cotidianas , Algoritmos , Actividades Humanas , Humanos
5.
Langenbecks Arch Surg ; 406(2): 497-502, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33420833

RESUMEN

PURPOSE: Esophagojejunostomy is a challenging step in laparoscopic gastrectomy. Although the overlap method is a safe and feasible approach for esophagojejunostomy, it has several technical limitations. We developed novel modifications for the overlap method to overcome these disadvantages. METHODS: Forty-eight consecutive gastric cancer patients underwent totally laparoscopic total gastrectomy or laparoscopic proximal gastrectomy with double-tract reconstruction at our institution from January 2019 to April 2020 using the overlap method with the following modifications. The esophagus was initially rotated by 90° counterclockwise, followed by transection of two-thirds of the esophageal diameter. The unstapled esophagus was then transected with a harmonic ultrasonic scalpel to enable esophagostomy at the posterior side of the esophagus. A side-to-side esophagojejunostomy was then formed at the posterior side of the esophagus using an endoscopic linear stapler through the right lower trocar. The common entry hole was closed via hand sewing method using V-Loc suture. This procedure was termed "esophagus two-step-cut overlap method." RESULTS: Only one patient suffered from esophagojejunal anastomotic leakage but subsequently recovered after conservative treatment. Patients did not experience anastomotic bleeding or stricture. CONCLUSION: Our modified overlap method provides satisfactory surgical outcomes and overcomes several technical limitations, such as entering the false lumen of the esophagus, unnecessary pollution caused by nasogastric tube, and unintended left crus stapling during anastomosis.


Asunto(s)
Laparoscopía , Neoplasias Gástricas , Anastomosis Quirúrgica , Esófago/cirugía , Gastrectomía/efectos adversos , Humanos , Yeyuno/cirugía , Neoplasias Gástricas/cirugía , Grapado Quirúrgico/efectos adversos
6.
Pharmaceuticals (Basel) ; 13(3)2020 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-32197544

RESUMEN

This network meta-analysis aimed to integrate the available direct and indirect evidence on regenerative injections-including 5% dextrose (D5W) and platelet-rich plasma (PRP)-for the treatment of carpal tunnel syndrome (CTS). Literature reports comparing D5W and PRP injections with non-surgical managements of CTS were systematically reviewed. The main outcome was the standardized mean difference (SMD) of the symptom severity and functional status scales of the Boston Carpal Tunnel Syndrome Questionnaire at three months after injections. Ranking probabilities of the SMD of each treatment were acquired by using simulation. Ten studies with 497 patients and comparing five treatments (D5W, PRP, splinting, corticosteroid, and normal saline) were included. The results of the simulation of rank probabilities showed that D5W injection was likely to be the best treatment, followed by PRP injection, in terms of clinical effectiveness in providing symptom relief. With respect to functional improvement, splinting ranked higher than PRP and D5W injections. Lastly, corticosteroid and saline injections were consistently ranked fourth and fifth in terms of therapeutic effects on symptom severity and functional status. D5W and PRP injections are more effective than splinting and corticosteroid or saline injection for relieving the symptoms of CTS. Compared with splinting, D5W and PRP injections do not provide better functional recovery. More studies investigating the long-term effectiveness of regenerative injections in CTS are needed in the future.

7.
ACS Nano ; 11(5): 4439-4444, 2017 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-28287703

RESUMEN

Reliably obtaining nanostructures of complex oxides over large area with nanoscale resolution and well-controlled shape, spacing, and pattern symmetry remains a major challenge. In this article, millions of nanowells have been routinely generated by beam pen lithography. Each attoliter volume nanowell functions as a "nanoreactor", inside which oxide nanostructures are synthesized from their sol-gel precursors. Importantly, these nanometer scale entities are in single crystalline or textured forms and epitaxial to the underlying substrates, which promises functionalities including ferroelectricity, ferromagnetism, and multiferroicity. This method provides a general solution which allows one to rapidly screen structural parameters of oxide nanostructures comprising of three or more elements for prominent properties.

8.
J Am Chem Soc ; 137(5): 1742-5, 2015 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-25608577

RESUMEN

Lithiation-exfoliation produces single to few-layered MoS2 and WS2 sheets dispersible in water. However, the process transforms them from the pristine semiconducting 2H phase to a distorted metallic phase. Recovery of the semiconducting properties typically involves heating of the chemically exfoliated sheets at elevated temperatures. Therefore, it has been largely limited to sheets deposited on solid substrates. Here, we report the dispersion of chemically exfoliated MoS2 sheets in high boiling point organic solvents enabled by surface functionalization and the controllable recovery of their semiconducting properties directly in solution. This process connects the scalability of chemical exfoliation with the simplicity of solution processing, ultimately enabling a facile method for tuning the metal to semiconductor transitions of MoS2 and WS2 within a liquid medium.


Asunto(s)
Disulfuros/química , Molibdeno/química , Semiconductores , Compuestos de Tungsteno/química , Modelos Moleculares , Conformación Molecular , Soluciones , Solventes/química , Propiedades de Superficie
9.
ACS Nano ; 8(10): 10851-7, 2014 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-25233478

RESUMEN

The palette of two-dimensional materials has expanded beyond graphene in recent years to include the chalcogenides among other systems. However, there is a considerable paucity of methods for controlled synthesis of mono- and/or few-layer two-dimensional materials with desirable quality, reproducibility, and generality. Here we show a facile top-down synthesis approach for ultrathin layers of 2D materials down to monolayer. Our method is based on controlled evaporative thinning of initially large sheets, as deposited by vapor mass-transport. Rather than optimizing conditions for monolayer deposition, our approach makes use of selective evaporation of thick sheets to control the eventual thickness, down to a monolayer, a process which appears to be self-stopping. As a result, 2D sheets with high yield, high reproducibility, and excellent quality can be generated with large (>10 µm) and thin (∼ 1-2 nm) dimensions. Evaporative thinning promises to greatly reduce the difficulty involved in isolating large, mono- and few-layers of 2D materials for subsequent studies.

10.
In Vivo ; 28(5): 967-71, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25189915

RESUMEN

Gastric cancer is the second cause of death from cancer worldwide and its prevalence and mortality rates are still very high in developed countries. Interleukin-10 (IL10) is a pleiotropic cytokine produced by macrophages which can suppress and stimulate the immune response in tumorigenesis signaling. However, the contribution of IL10 genomic variants to gastric cancer is still largely unknown. In the present study, we aimed at investigating the role of IL10 genotypes in gastric cancer risk. The promoter single nucleotide polymorphisms on IL10, A-1082G (rs1800896), T-819C (rs3021097) and A-592C (rs1800872), were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method among 716 Taiwanese people (358 patients gastric cancer and 358 cancer-free controls). The results showed that there was a significant difference between the patient and control groups in the genotypic frequency distribution of IL10 A-1082G genotypes (p=0.0004). In addition, those carrying the G allele were found to have a higher risk for gastric cancer compared with those with the A allele (p=3.19×10(-5)). Furthermore, personal cigarrete smoking habits enhanced the gastric cancer risk for those IL10 A-1082G AG and GG carriers. In conclusion, AG and GG genotype at IL10 A-1082G, together with smoking, synergistically contribute to individual susceptibility for gastric cancer in Taiwan.


Asunto(s)
Interleucina-10/genética , Polimorfismo de Nucleótido Simple , Fumar/efectos adversos , Neoplasias Gástricas/etiología , Anciano , Alelos , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Riesgo , Neoplasias Gástricas/epidemiología , Taiwán
11.
ACS Nano ; 7(6): 4879-91, 2013 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-23713986

RESUMEN

Most of recent research on layered chalcogenides is understandably focused on single atomic layers. However, it is unclear if single-layer units are the most ideal structures for enhanced gas-solid interactions. To probe this issue further, we have prepared large-area MoS2 sheets ranging from single to multiple layers on 300 nm SiO2/Si substrates using the micromechanical exfoliation method. The thickness and layering of the sheets were identified by optical microscope, invoking recently reported specific optical color contrast, and further confirmed by AFM and Raman spectroscopy. The MoS2 transistors with different thicknesses were assessed for gas-sensing performances with exposure to NO2, NH3, and humidity in different conditions such as gate bias and light irradiation. The results show that, compared to the single-layer counterpart, transistors of few MoS2 layers exhibit excellent sensitivity, recovery, and ability to be manipulated by gate bias and green light. Further, our ab initio DFT calculations on single-layer and bilayer MoS2 show that the charge transfer is the reason for the decrease in resistance in the presence of applied field.

12.
Small ; 9(16): 2730-4, 2013 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-23427106

RESUMEN

Field emission studies are reported for the first time on layered MoS2 sheets at the base pressure of ∼1 × 10⁻8 mbar. The turn-on field required to draw a field emission current density of 10 µA/cm² is found to be 3.5 V/µm for MoS2 sheets. The turn-on values are found to be significantly lower than the reported MoS2 nanoflowers, graphene, and carbon nanotube-based field emitters due to the high field enhancement factor (∼1138) associated with nanometric sharp edges of MoS2 sheet emitter surface. The emission current-time plots show good stability over a period of 3 h. Owing to the low turn-on field and planar (sheetlike) structure, the MoS2 could be utilized for future vacuum microelectronics/nanoelectronic and flat panel display applications.

13.
J Am Chem Soc ; 133(39): 15264-7, 2011 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-21894991

RESUMEN

Oxidative etching of graphene flakes was observed to initiate from edges and the occasional defect sites in the basal plane, leading to reduced lateral size and a small number of etch pits. In contrast, etching of highly defective graphene oxide and its reduced form resulted in rapid homogeneous fracturing of the sheets into smaller pieces. On the basis of these observations, a slow and more controllable etching route was designed to produce nanoporous reduced graphene oxide sheets by hydrothermal steaming at 200 °C. The degree of etching and the concomitant porosity can be conveniently tuned by etching time. In contrast to nonporous reduced graphene oxide annealed at the same temperature, the steamed nanoporous graphene oxide exhibited nearly 2 orders of magnitude increase in the sensitivity and improved recovery time when used as chemiresistor sensor platform for NO(2) detection. The results underscore the efficacy of the highly distributed nanoporous network in the low temperature steam etched GO.

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