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1.
Microb Pathog ; 192: 106667, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38685361

RESUMEN

OBJECTIVE: The dysbiosis of the gut microbiota has been implicated in various maladies. Research has identified an association between the dysbiosis of the gut microbiota and the risk of constipation, prompting this study to elucidate the potential causal relationship between gut microbiota imbalance with constipation through a two sample bidirectional Mendelian randomization (MR) study, shedding light on the genetic mechanisms underlying the connection between gut microbiota and constipation. METHODS: The forward MR analysis aimed to scrutinize whether alterations in the composition and abundance of gut microbiota impact the risk of constipation, while the reverse MR analysis explored whether the genetic predisposition to constipation influences the abundance of gut microbiota. Genomic correlation data for the gut microbiota were sourced from the comprehensive statistics of the MiBioGen consortium. Genomic correlation data for constipation were obtained from the IEU database, encoded as the dataset ebi-a-GCST90018829. The correlation was assessed using various analytical techniques, including inverse variance weighting (IVW), Mendelian randomization-Egger regression (MR-Egger), and weighted median and mode methodologies. To ensure the robustness of the results, a meticulous sensitivity analysis was conducted, incorporating Cochran's Q test, MR-Egger intercept test, Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO), and a Leave-one-out analysis. RESULTS: In the forward Mendelian randomization analyses, a negative correlation was discerned between the abundance of Coprococcus in the gut microbiota and the occurrence of constipation (IVW: OR = 0.74, 95 % CI = 0.64-0.86, p = 0.0001), whereas a positive correlation was observed between the abundance of Bacteroidetes in the gut microbiota and constipation (IVW: OR = 1.22, 95 % CI = 1.00-1.50, p = 0.04). In the forward Mendelian randomization analyses, we were unsuccessful in obtaining valid instrumental variables for scrutiny, and we deemed that constipation exerts no influence on the composition of the gut microbiota. CONCLUSION: Genetic predisposition towards increased abundance of Coprococcus and decreased abundance of Bacteroidetes is correlated with a diminished susceptibility to constipation. This investigation showed that alterations in the gut microbiota precipitated the onset of constipation, rather than constipation inducing modifications in the microbial flora.


Asunto(s)
Estreñimiento , Microbioma Gastrointestinal , Análisis de la Aleatorización Mendeliana , Humanos , Microbioma Gastrointestinal/genética , Estreñimiento/microbiología , Estreñimiento/genética , Disbiosis , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple
2.
J Chem Inf Model ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953249

RESUMEN

Deep learning holds great potential for expediting the discovery of new polymers from the vast chemical space. However, accurately predicting polymer properties for practical applications based on their monomer composition has long been a challenge. The main obstacles include insufficient data, ineffective representation encoding, and lack of explainability. To address these issues, we propose an interpretable model called the Polymer Graph Convolutional Neural Network (PGCNN) that can accurately predict various polymer properties. This model is trained using the RadonPy data set and validated using experimental data samples. By integrating evidential deep learning with the model, we can quantify the uncertainty of predictions and enable sample-efficient training through uncertainty-guided active learning. Additionally, we demonstrate that the global attention of the graph embedding can aid in discovering underlying physical principles by identifying important functional groups within polymers and associating them with specific material attributes. Lastly, we explore the high-throughput screening capability of our model by rapidly identifying thousands of promising candidates with low and high thermal conductivity from a pool of one million hypothetical polymers. In summary, our research not only advances our mechanistic understanding of polymers using explainable AI but also paves the way for data-driven trustworthy discovery of polymer materials.

3.
BMC Med Inform Decis Mak ; 24(1): 39, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38321399

RESUMEN

INTRODUCTION: Incarceration occurred in approximately 5% to 15% of inguinal hernia patients, with around 15% of incarcerated cases progressing to intestinal necrosis, necessitating bowel resection surgery. Patients with intestinal necrosis had significantly higher mortality and complication rates compared to those without necrosis.The primary objective of this study was to design and validate a diagnostic model capable of predicting intestinal necrosis in patients with incarcerated groin hernias. METHODS: We screened the clinical records of patients who underwent emergency surgery for incarcerated inguinal hernia between January 1, 2015, and December 31, 2022. To ensure balanced representation, the enrolled patients were randomly divided into a training set (n = 180) and a validation set (n = 76) using a 2:1 ratio. Logistic regression analysis was conducted using the rms package in R software, incorporating selected features from the LASSO regression model, to construct a predictive model. RESULTS: Based on the results of the LASSO regression analysis, a multivariate logistic regression model was developed to establish the predictive model. The predictors included in the model were Abdominal effusion, Hernia Sac Effusion, and Procalcitonin. The area under the receiver operating characteristic (ROC) curve for the nomogram graph in the training set was 0.977 (95% CI = 0.957-0.992). In the validation set, the AUC for the nomogram graph was 0.970. Calibration curve and decision curve analysis (DCA) verified the accuracy and practicability of the nomogram graph in our study. CONCLUSION: Bowel necrosis in patients with incarcerated inguinal hernia was influenced by multiple factors. The nomogram predictive model constructed in this study could be utilized to predict and differentiate whether incarcerated inguinal hernia patients were at risk of developing bowel necrosis.


Asunto(s)
Hernia Inguinal , Humanos , Hernia Inguinal/complicaciones , Hernia Inguinal/cirugía , Modelos Logísticos , Necrosis/complicaciones , Estudios Retrospectivos
4.
Langmuir ; 39(36): 12762-12773, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37642387

RESUMEN

Formaldehyde (HCHO) poses a grave threat to human health because of its toxicity, but its accurate, sensitive, and rapid detection in aqueous solutions remains a major challenge. This study proposes a novel electrochemical sensor composed of a graphene-based electrode that is prepared via laser induction technology. The precursor material, polyimide, is modified via the metal ion exchange method, and the detective electrode is coated with graphene and silver nanoparticles. And the special structure of graphene-coated Ag was demonstrated using scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM), and X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS) results show that graphene provides more sites for Ag NRs to be exposed and increases the surface area of contact between the solution and the detection object. In addition, differential pulse voltammetry (DPV) analysis exhibits high linearity over the HCHO concentration range from 0.05 to 5 µg/mL, with a detection limit of 0.011 µg/mL (S/N = 3). The Ag NPs in the electrochemical reaction will adsorb the intermediate •CO and •OH, catalyze their combination, and finally convert to CO2 and H2O, respectively. A microdetection device, specially designed for use with commercial micro-workstations, is employed to fully demonstrate the practical application of the electrode, which paves a way for developing formaldehyde electrochemical sensors.

5.
Nano Lett ; 21(17): 7388-7395, 2021 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-34424703

RESUMEN

Highly compact, filter-free multispectral photodetectors have important applications in biological imaging, face recognition, and remote sensing. In this work, we demonstrate room-temperature wavelength-selective multipixel photodetectors based on GaAs0.94Sb0.06 nanowire arrays grown by metalorganic vapor phase epitaxy, providing more than 10 light detection channels covering both visible and near-infrared ranges without using any optical filters. The nanowire array geometry-related tunable spectral photoresponse has been demonstrated both theoretically and experimentally and shown to be originated from the strong and tunable resonance modes that are supported in the GaAsSb array nanowires. High responsivity and detectivity (up to 44.9 A/W and 1.2 × 1012 cm √Hz/W at 1 V, respectively) were obtained from the array photodetectors, enabling high-resolution RGB color imaging by applying such a nanowire array based single pixel imager. The results indicate that our filter-free wavelength-selective GaAsSb nanowire array photodetectors are promising candidates for the development of future high-quality multispectral imagers.


Asunto(s)
Nanocables , Diagnóstico por Imagen
6.
Small ; 17(21): e2100263, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33856732

RESUMEN

There is a strong demand for III-V nanostructures of different geometries and in the form of interconnected networks for quantum science applications. This can be achieved by selective area epitaxy (SAE) but the understanding of crystal growth in these complicated geometries is still insufficient to engineer the desired shape. Here, the shape evolution and crystal structure of InP nanostructures grown by SAE on InP substrates of different orientations are investigated and a unified understanding to explain these observations is established. A strong correlation between growth direction and crystal phase is revealed. Wurtzite (WZ) and zinc-blende (ZB) phases form along <111>A and <111>B directions, respectively, while crystal phase remains the same along other low-index directions. The polarity induced crystal structure difference is explained by thermodynamic difference between the WZ and ZB phase nuclei on different planes. Growth from the openings is essentially determined by pattern confinement and minimization of the total surface energy, regardless of substrate orientations. A novel type-II WZ/ZB nanomembrane homojunction array is obtained by tailoring growth directions through alignment of the openings along certain crystallographic orientations. The understanding in this work lays the foundation for the design and fabrication of advanced III-V semiconductor devices based on complex geometrical nanostructures.

7.
Foodborne Pathog Dis ; 18(5): 306-314, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33769083

RESUMEN

Bacillus cereus is a common foodborne pathogen that can cause both gastrointestinal and nongastrointestinal diseases. In this study, we collected 603 meat and meat products from 39 major cities in China. The positive contamination rate of B. cereus in the collected samples was 26.37% (159/603), and the contamination level in 5.03% (8/159) positive samples exceeded 1100 most probable number/g. The detection rates of virulence genes were 89.7% for the nheABC gene group, 37.1% for the hblACD gene cluster, 82.3% for cytK-2, and 2.9% for cesB. Notably, all isolates presented with multiple antibiotic resistance, and 99.43% of isolates were resistant to five classes of antibiotics. In addition, the multilocus sequence typing results indicated that all isolates were rich in genetic diversity. Collectively, we conducted a systematic investigation on the prevalence and characterization of B. cereus in meat and meat products in China, providing crucial information for assessing the risk of B. cereus occurrence in meat and meat products.


Asunto(s)
Bacillus cereus/aislamiento & purificación , Farmacorresistencia Bacteriana Múltiple/genética , Microbiología de Alimentos/estadística & datos numéricos , Productos de la Carne/microbiología , Carne/microbiología , Animales , Antibacterianos/farmacología , Bacillus cereus/genética , China/epidemiología , Tipificación de Secuencias Multilocus , Prevalencia , Factores de Virulencia/genética , Factores de Virulencia/aislamiento & purificación
8.
Opt Express ; 28(11): 16795-16804, 2020 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-32549494

RESUMEN

Nominal dopant-free zinc blende twinning superlattice InP nanowires have been grown with high crystal-quality and taper-free morphology. Here, we demonstrate its superior optical performance and clarify the different carrier recombination mechanisms at different temperatures using a time resolved photoluminescence study. The existence of regular twin planes and lateral overgrowth do not significantly increase the defect density. At room temperature, the as-grown InP nanowires have a strong emission at 1.348 eV and long minority carrier lifetime (∼3 ns). The carrier recombination dynamics is mainly dominated by nonradiative recombination due to surface trapping states; a wet chemical etch to reduce the surface trapping density thus boosts the emission intensity and increases the carrier lifetime to 7.1 ns. This nonradiative recombination mechanism dominates for temperatures above 155 K, and the carrier lifetime decreases with increasing temperature. However, radiative recombination dominates the carrier dynamics at temperature below ∼75 K, and a strong donor-bound exciton emission with a narrow emission linewidth of 4.5 meV is observed. Consequently, carrier lifetime increases with temperature. By revealing carrier recombination mechanisms over the temperature range 10-300 K, we demonstrate the attraction of using InP nanostructure for photonics and optoelectronic applications.

9.
Arch Virol ; 165(4): 877-889, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32056002

RESUMEN

Outbreaks of porcine epidemic diarrhea (PED) caused by porcine epidemic diarrhea virus (PEDV) infection have caused high mortality of piglets and significant economic losses to the Chinese swine industry. In the current study, 184 specimens from pigs with or without signs of diarrhea were collected from 39 farms across eight provinces, mainly around Hunan, People's Republic of China, in 2017 to 2018 in order to obtain epidemiological information on PEDV infections in these regions. The results indicated an average PEDV-positive rate of 38.04% (70/184) and more-pronounced disease severity in diarrheic pigs (48.76%; 59/121) than in non-diarrheic pigs (17.46%; 11/63). Phylogenetic and sequence analysis demonstrated that 14 representative PEDV strains from 14 swine farms belonged to the G2 group (G2-a and G2-b subgroups) and displayed a high degree of genetic variation. In particular, two out of the 14 PEDV strains were found to have unique indels in the S1 gene. The strain HN-SY-2017-Oct had a 9-nucleotide (T1152GAAGCCAAT1160T) insertion, and the strain ZJ-2018-May had a 3-nucleotide (AAA) deletion at position 1126 in the S1 gene. A three-dimensional structural prediction revealed that these unique insertions might lengthen the loop on the surface or increase the likelihood of the surface protein being phosphorylated at 388Y, thereby affecting the virulence or pathogenicity of PEDV. Collectively, the data show that PED remains a severe threat to the pig industry and that variant PEDV stains are circulating in China. The updated PEDV epidemiological data will facilitate the design of PEDV vaccines and the application of effective measures for PED prevention.


Asunto(s)
Infecciones por Coronavirus/veterinaria , Diarrea/veterinaria , Virus de la Diarrea Epidémica Porcina/genética , Virus de la Diarrea Epidémica Porcina/aislamiento & purificación , Enfermedades de los Porcinos/virología , Secuencia de Aminoácidos , Animales , China/epidemiología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Diarrea/virología , Brotes de Enfermedades , Epidemias/estadística & datos numéricos , Variación Genética , Epidemiología Molecular , Filogenia , Virus de la Diarrea Epidémica Porcina/clasificación , Alineación de Secuencia , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Porcinos , Enfermedades de los Porcinos/epidemiología
10.
Nanotechnology ; 31(24): 244002, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-32131061

RESUMEN

Surface passivation of semiconductor nanowires (NWs) is important for their optoelectronic properties and applications. Here, the in situ passivation effect of an epitaxial InP shell and the corresponding photodetector performance is experimentally studied. Compared with the unpassivated GaAs1- x Sb x core-only NWs, the GaAs1- x Sb x /InP core/shell NWs have shown much stronger photoluminescence and cathodoluminescence intensities. Correspondingly, the fabricated single GaAs1- x Sb x /InP core/shell NW photodetector shows a responsivity of 325.1 A W-1 (@ 1.3 µm and 1.5 V) that is significantly enhanced compared to that of single GaAs1- x Sb x core-only NW photodetectors (143.5 A W-1), with a comparable detectivity of 4.7 × 1010 and 5.3 × 1010 cm√Hz/W, respectively. This is ascribed to the enhanced carrier mobility and carrier concentration by the in situ passivation, which lead to both higher photoconductivity and dark-conductivity. Our results show that in situ passivation is an effective approach for performance enhancement of GaAs1-x Sb x NW based optoelectronic devices.

11.
Nano Lett ; 19(7): 4490-4497, 2019 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-31188620

RESUMEN

Taper-free InP twinning superlattice (TSL) nanowires with an average twin spacing of ∼13 nm were grown along the zinc-blende close-packed [111] direction using metalorganic vapor phase epitaxy. The mechanical properties and fracture mechanisms of individual InP TSL nanowires in tension were ascertained by means of in situ uniaxial tensile tests in a transmission electron microscope. The elastic modulus, failure strain, and tensile strength along the [111] direction were determined. No evidence of inelastic deformation mechanisms was found before fracture, which took place in a brittle manner along the twin boundary. The experimental results were supported by molecular dynamics simulations of the tensile deformation of the nanowires that also showed that the fracture of twinned nanowires occurred in the absence of inelastic deformation mechanisms by the propagation of a crack from the nanowire surface along the twin boundary.

12.
Nano Lett ; 19(8): 5062-5069, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31242390

RESUMEN

We use transient Rayleigh scattering to study the thermalization of hot photoexcited carriers in single GaAs0.7Sb0.3/InP nanowire heterostructures. By comparing the energy loss rate in single core-only GaAs0.7Sb0.3 nanowires which do not show substantial hot carrier effects with the core-shell nanowires, we show that the presence of an InP shell substantially suppresses the longitudinal optical phonon emission rate at low temperatures which then leads to strong hot carrier effects.

13.
Cell Physiol Biochem ; 49(4): 1342-1351, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30205381

RESUMEN

BACKGROUND/AIMS: The gut-vascular barrier (GVB) has recently been depicted to dampen the bacterial invasion of the bloodstream. The intestinal mucosa is a tissue rich in small vessels including capillaries. In this study, the protective effect of berberine on GVB in small bowel mucosa was investigated. METHODS: The rat cecal ligation and puncture (CLP) sepsis model was employed to evaluate the effect of berberine on serum endotoxin level and intestinal vascular permeability to Evans blue in vivo. The rat intestinal microvascular endothelial cells (RIMECs) treated by lipopolysaccharide (LPS) were used to assess the effect of berberine on endothelial permeability to FITC-labeled dextran, transendothelial electrical resistance (TEER), and tight junction (TJ) and adherens junction (AJ) expression in vitro. RESULTS: After 24-hr CLP operation the serum endotoxin concentration and gut vascular permeability were significantly increased, while berberine markedly reduced endotoxin level and vascular leakage. In vitro, LPS not only dramatically increased endothelial permeability of RIMECs to FITC-dextran, but also decreased TEER and inhibited claudin-12, beta-catenin and VE-cadherin expression. These effects of LPS were antagonized by berberine. In addition, our in vivo and vitro studies also confirmed that the effect of berberine on GVB could be partially abolished by ICG001. CONCLUSION: Berberine exerted a protective effect on GVB function in sepsis, which was strictly related to the modulation of the Wnt/beta-catenin signaling pathway.


Asunto(s)
Berberina/farmacología , Permeabilidad Capilar/efectos de los fármacos , Mucosa Intestinal/metabolismo , Sustancias Protectoras/farmacología , Vía de Señalización Wnt/efectos de los fármacos , Animales , Antígenos CD/metabolismo , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Cadherinas/metabolismo , Claudinas/metabolismo , Modelos Animales de Enfermedad , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Endotoxinas/sangre , Mucosa Intestinal/efectos de los fármacos , Lipopolisacáridos/farmacología , Masculino , Pirimidinonas/farmacología , Ratas , Ratas Long-Evans , Sepsis/tratamiento farmacológico , Sepsis/mortalidad , Sepsis/patología , Tasa de Supervivencia , Uniones Estrechas/metabolismo , beta Catenina/metabolismo
14.
Nano Lett ; 16(8): 5080-6, 2016 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-27459233

RESUMEN

We present the design and room-temperature lasing characteristics of single nanowires containing coaxial GaAs/AlGaAs multiple quantum well (MQW) active regions. The TE01 mode, which has a doughnut-shaped intensity profile and is polarized predominantly in-plane to the MQWs, is predicted to lase in these nanowire heterostructures and is thus chosen for the cavity design. Through gain and loss calculations, we determine the nanowire dimensions required to minimize loss for the TE01 mode and determine the optimal thickness and number of QWs for minimizing the threshold sheet carrier density. In particular, we show that there is a limit to the minimum and maximum number of QWs that are required for room-temperature lasing. Based on our design, we grew nanowires of a suitable diameter containing eight uniform coaxial GaAs/AlGaAs MQWs. Lasing was observed at room temperature from optically pumped single nanowires and was verified to be from TE01 mode by polarization measurements. The GaAs MQW nanowire lasers have a threshold fluence that is a factor of 2 lower than that previously demonstrated for room-temperature GaAs nanowire lasers.

15.
Nanotechnology ; 27(43): 435205, 2016 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-27659444

RESUMEN

Single nanowire (NW) green InGaN/GaN light-emitting diodes (LEDs) were fabricated by top-down etching technology. The electroluminescence (EL) peak wavelength remains approximately constant with an increasing injection current in contrast to a standard planar LED, which suggests that the quantum-confined Stark effect is significantly reduced in the single NW device. The strain relaxation mechanism is studied in the single NW LED using Raman scattering analysis. As compared to its planar counterpart, the EL peak of the NW LED shows a redshift, due to electric field redistribution as a result of changes in the cavity mode pattern after metallization. Our method has important implication for single NW optoelectronic device applications.

16.
World J Surg Oncol ; 14(1): 252, 2016 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-27669818

RESUMEN

BACKGROUND: Epithelial dysplasia and adenomatous polyps of colorectum are precancerous lesions. Surgical removal is still one of the important treatment approaches for colorectal polyps. CASE PRESENTATION: A male patient over 78 years was admitted due to bloody stool and abdominal pain. Colonoscopic biopsy showed a high-grade epithelial dysplasia in an adenomatous polyp of sigmoid colon. Anemia, COPD, ischemic heart disease (IHD), arrhythmias, and hypoproteinemia were comorbidities. The preoperative preparation was carefully made consisting of oral nutritional supplements (ONS), blood transfusion, cardiorespiratory management, and hemostatic therapy. However, his illness did not improve but deteriorate mainly due to polyp rebleeding during preparative period. The open polypectomy was performed within 60 min under epidural anesthesia. Postoperative treatments included oxygen inhalation, bronchodilation, parenteral and enteral nutrition, human serum albumin, antibiotics, and blood transfusion. Unluckily, these did not significantly facilitate to surgical recovery on account of severe comorbidities and complications. The most serious complications were colonic leakage and secondary abdominal severe infection. The patient finally gave up treatment due to multiple organ dysfunction syndromes. CONCLUSIONS: The polypectomy for colonic polyp is a seemingly minor but potentially deadly surgery for patients with severe comorbidities, and prophylactic ostomy should be considered for the safety.

17.
Nanotechnology ; 26(44): 445202, 2015 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-26451616

RESUMEN

Antimonide-based ternary III-V nanowires (NWs) allow for a tunable bandgap over a wide range, which is highly interesting for optoelectronics applications, and in particular for infrared photodetection. Here we demonstrate room temperature operation of GaAs0.56Sb0.44 NW infrared photodetectors grown by metal organic vapor phase epitaxy. These GaAs0.56Sb0.44 NWs have uniform axial composition and show p-type conductivity with a peak field-effect mobility of ∼12 cm(2) V(-1) s(-1)). Under light illumination, single GaAs0.56Sb0.44 NW photodetectors exhibited typical photoconductor behavior with an increased photocurrent observed with the increase of temperature owing to thermal activation of carrier trap states. A broadband infrared photoresponse with a long wavelength cutoff at ∼1.66 µm was obtained at room temperature. At a low operating bias voltage of 0.15 V a responsivity of 2.37 (1.44) A/W with corresponding detectivity of 1.08 × 10(9) (6.55 × 10(8)) cm√Hz/W were achieved at the wavelength of 1.3 (1.55) µm, indicating that ternary GaAs0.56Sb0.44 NWs are promising photodetector candidates for small footprint integrated optical telecommunication systems.

18.
Sensors (Basel) ; 15(11): 28005-30, 2015 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-26556357

RESUMEN

Wireless Body Area Networks (WBANs) can provide real-time and reliable health monitoring, attributing to the human-centered and sensor interoperability properties. WBANs have become a key component of the ubiquitous eHealth (electronic health) revolution that prospers on the basis of information and communication technologies. The prime consideration in WBAN is how to maximize the network lifetime with battery-powered sensor nodes in energy constraint. Novel solutions in Medium Access Control (MAC) protocols are imperative to satisfy the particular BAN scenario and the need of excellent energy efficiency in healthcare applications. In this paper, we propose a hybrid Lifetime Extended Directional Approach (LEDA) MAC protocol based on IEEE 802.15.6 to reduce energy consumption and prolong network lifetime. The LEDA MAC protocol takes full advantages of directional superiority in energy saving that employs multi-beam directional mode in Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) and single-beam directional mode in Time Division Multiple Access (TDMA) for alternative in data reservation and transmission according to the traffic varieties. Moreover, the impacts of some inherent problems of directional antennas such as deafness and hidden terminal problem can be decreased owing to that all nodes generate individual beam according to user priorities designated. Furthermore, LEDA MAC employs a Dynamic Polled Allocation Period (DPAP) for burst data transmissions to increase the network reliability and adaptability. Extensive analysis and simulation results show that the proposed LEDA MAC protocol achieves extended network lifetime with improved performance compared with IEEE 802.15.6.


Asunto(s)
Redes de Comunicación de Computadores/instrumentación , Tecnología de Sensores Remotos/instrumentación , Tecnología Inalámbrica/instrumentación , Diseño de Equipo , Humanos
19.
Tumour Biol ; 35(11): 11513-21, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25128063

RESUMEN

The main purpose of this study is to investigate the interactions between Lin28 and Her2 in gastric cancer. Lin28 and Her2 expression were evaluated in surgically resected samples of 298 gastric cancer patients using immunohistochemical staining. The correlations between Lin28/Her2 expression and clinical variables were retrospectively analyzed. The mRNA level of LIN28 and HER2 was detected by reverse-transcriptase polymerase chain reaction. Among all gastric cancer patients, 33.9% (101/298) were determined as Her2-positive, and 43.0% (128/298) were defined as Lin28-positive. Lin28 was significantly associated with Her2, advanced tumor stage, lesion size, and Ki67 level (p<0.05 for each). Kaplan-Meier analysis illustrated that both Lin28 and Her2 are poor prognostic factors in gastric cancer; Lin28(+)/Her2(+) patients have the poorest survival (median survival = 17 months, p<0.01). Multivariate Cox analysis showed that Lin28 is a significant prognostic factor (hazard ratio (HR) = 1.79, 95% confidence interval (CI) 1.23-2.62). Further stratification analysis indicated that Lin28 may be a prognostic factor in chemotherapy. In vitro data on MKN-28 and MKN-45 cells showed that Lin28 can upregulate Her2 expression at translational level. Both Lin28 and Her2 are poor prognostic factors in gastric cancer. Lin28 may regulate Her2 post-transcriptionally in gastric cancer cells, which indicates it might be a potential target in the treatment of gastric cancer.


Asunto(s)
Adenocarcinoma/metabolismo , Biomarcadores de Tumor/metabolismo , Proteínas de Unión al ARN/metabolismo , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Western Blotting , Proliferación Celular , Femenino , Estudios de Seguimiento , Humanos , Técnicas para Inmunoenzimas , Metástasis Linfática , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Invasividad Neoplásica , Estadificación de Neoplasias , Pronóstico , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor ErbB-2/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Tasa de Supervivencia , Células Tumorales Cultivadas
20.
Zhonghua Yi Xue Za Zhi ; 94(11): 836-9, 2014 Mar 25.
Artículo en Zh | MEDLINE | ID: mdl-24854751

RESUMEN

OBJECTIVE: To assess the efficacies of proximal femoral nail antirotation (PFNA) versus dynamic hip screw (DHS) for intertrochanteric fracture in elders. METHODS: The databases of PubMed, Embase, CENTRAL, CBM, CNKI and WANFANG were searched for the relevant randomized controlled trials (RCTs) up to May 18, 2013. After quality evaluation and data extraction by two authors independently, meta-analyses were performed with the RevMan5.1 software. And the levels of evidence were evaluated by the GRADEprofile 3.6 software. RESULTS: A total of 17 studies (n = 1 344) were included and there were 656 patients in PFNA group and 688 in DHS respectively. Meta-analyses showed that, as compared with DHS, PFNA could significantly decrease fixation failure rate (odds ratio (OR) = 0.26, 95% confidence interval (CI) = [0.12, 0.57], P = 0.0008), reduce average fracture healing time (weighted mean difference (WMD) = -15.11, 95%CI = [-24.36, -5.85], P = 0.001), improve excellent and good rate for Harris score (OR = 0.29, 95%CI = [0.15, 0.56], P = 0.0002), yield a higher Harris score (WMD = 6.88, 95%CI = [0.96, 12.80], P = 0.02) and reduce the rate of coxa vara (OR = 0.40, 95%CI = [0.18,0.92], P = 0.03). However, there was no statistical significance in 1-year mortality, postoperative nonunion and delayed union, postoperative femoral head necrosis, postoperative femoral fractures or femoral head necrosis. The importance of outcomes was "critical". And the level of evidences based on the GRADE approach was from "very low" to "low". CONCLUSION: PFNA is superior to DHS. Due to the limitations of the included studies, more large-sample and high-quality RCTs are required. And subgroup analysis based on fracture types should be performed.


Asunto(s)
Clavos Ortopédicos , Tornillos Óseos , Fracturas del Fémur/cirugía , Fijación Interna de Fracturas/instrumentación , Fijación Intramedular de Fracturas/instrumentación , Humanos , Resultado del Tratamiento
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