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1.
Materials (Basel) ; 16(23)2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-38068094

RESUMEN

The binary compound Mg3Sb2 (also written as MgMg2Sb2) exhibits a much lower lattice thermal conductivity (κL) than its ternary analog CaMg2Sb2, despite its relatively low mass density and simple crystalline structure. Here, we perform a comparative first-principles study of the lattice dynamics in MgMg2Sb2 and CaMg2Sb2 based on the density functional theory, together with the self-consistent phonon theory and the Boltzmann transport theory. We show that the modest anharmonicity of CaMg2Sb2 renders the three-phonon processes dominant, and the temperature dependence of κL approximately follows the T-1 relationship. In contrast, the strong quartic anharmonicity of MgMg2Sb2 leads to the ultralow κL and weak temperature dependence, in agreement with the experimental observations. A comprehensive analysis reveals that the κLs in the two compounds are mainly carried by the acoustic phonons associated with the Sb atoms, and the different behaviors of κL result from the chemical bond changes around Sb atoms, which bond more covalently with the Mg atoms than the Ca atoms and thus lead to high-order anharmonicity in MgMg2Sb2. These results give us insights into the understanding of the anomalous thermal transport in thermoelectric materials.

2.
Int J Surg ; 109(5): 1158-1168, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37057900

RESUMEN

BACKGROUND: Frequent in-out-in femoral neck screws were reported potential huge iatrogenic-injury risks, related to axial safe target area (ASTA) of femoral neck screws channel. However, orientated-quantitative ASTA based on stable coordinate system was unreported before. METHODS: Three-dimensional reconstruction was performed on computed tomography (CT) images of 139 intact normal hips, and the intersection area, defined as ASTA, was obtained by superimposing the axial CT images of each femoral neck. Taking anterior cortex of femoral neck basilar (AC-FNB) as landmark, a coordinate system was established to measure the anterior-posterior diameter (D-AP), the superior-inferior diameter (D-SI) and the oblique angle respectively. Each intersection was overlaid up to the axial CT images to determine the coronal location of the ASTA boundaries. RESULTS: Each ASTA presented an inclined rounded triangle with a flat anterior base coincided with AC-FNB. There were significant sex differences in D-SI (male: 33.6±2.3 vs. female: 29.4±1.9 mm) and D-AP (male: 25.3±2.1 vs. 21.9±1.9 mm), P <0.001. D-SI was found to be positively correlated with D-AP ( R2 =0.6). All fluoroscopic visible border isthmus completely matched the corresponding ASTA boundaries. The oblique angle was 5-53° (male: 28.1±10.3°, female: 27.1±8.2°) without significant difference between sexes. CONCLUSION: The intersection method was employed to conveniently acquire orientated-quantitative individualized ASTA. Under this coordinate system, x-ray data of screws could be converted to axial coordinates in CT ASTA, which could help surgeons design combined screws configuration preoperatively and evaluate quantitatively their axial position intraoperatively.


Asunto(s)
Fracturas del Cuello Femoral , Cuello Femoral , Humanos , Masculino , Femenino , Tornillos Óseos/efectos adversos , Fémur/cirugía , Tomografía Computarizada por Rayos X/métodos , Fluoroscopía , Fijación Interna de Fracturas/métodos , Fracturas del Cuello Femoral/cirugía
3.
Comput Math Methods Med ; 2022: 7074525, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35813432

RESUMEN

Background: Total knee arthroplasty is one of the most effective methods for the treatment of end-stage knee osteoarthritis, but 10% of patients still show insufficient function, strength, and mobility. Continuous nursing service plays an important role in the rehabilitation of patients undergoing total knee arthroplasty. For discharged and convalescent patients, the traditional follow-up model cannot solve the nursing problems of discharged patients. How to meet the health needs of discharged patients under the limited nursing resources has become an existing problem. Objective: To explore the effect of proprioception and balance training combined with continuous nursing on Berg balance scale (BBS) score and Hospital for Special Surgery (HSS) score of patients undergoing total knee arthroplasty (TKA) is the objective of this study. Methods: Sixty patients undergoing TKA in our hospital from December 2019 to April 2021 were enrolled. The patients were randomly assigned into the control group and the study group. The control group received continuous nursing, and the study group received proprioception and balance training combined with continuous nursing. Results: The nursing satisfaction of the study group was higher than that of the control group (P < 0.05). The HSS scores at discharge, 1 month, 3 months, and 6 months after discharge in the study group were higher than those in the control group (P < 0.05). It was higher in the study group than in the control group at 1 month, 3 months, and 6 months after discharge (P < 0.05). The pain catastrophizing score of the study group at discharge was lower than that of the control group at 1 month, 3 months, and 6 months after discharge (P < 0.05). The BBS scores at discharge, 1 month, 3 months, and 6 months after discharge in the study group were higher than those in the control group (P < 0.05). The Lindmark balance scores at discharge, 1 month, 3 months, and 6 months after discharge in the study group were lower than those in the control group (P < 0.05). Conclusion: Proprioception and balance training combined with continuous nursing can effectively promote the recovery of knee joint function of patients after TKA, enhance patients' pain catastrophizing grade, enhance patients' quality of life, effectively promote patients' knee joint function and BBS score, and promote the improvement of disease.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla , Artroplastia de Reemplazo de Rodilla/métodos , Hospitales , Humanos , Articulación de la Rodilla , Osteoartritis de la Rodilla/rehabilitación , Osteoartritis de la Rodilla/cirugía , Propiocepción , Calidad de Vida , Resultado del Tratamiento
4.
Cancer Med ; 11(24): 4900-4912, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35587572

RESUMEN

BACKGROUND: Stage IV colorectal cancer patients with liver metastasis represent a special group of CRC patients with poor prognosis. The prognostic factors have not been investigated for stage IV CRC patients undergoing primary cancer resection but not candidates for metastasis resection. METHODS: Ninety-nine stage IV CRC patients who underwent primary cancer resection without metastasis resection were retrospectively recruited. Both whole-exome sequencing (WES) and RNA-seq were performed with frozen primary cancer tissues, using para-cancerous normal tissues as the control. Valid data were obtained from 78 patients for WES and 84 patients for RNA-seq. Univariate, multivariate Cox analyses were performed and Nomogram model was established to predict patient prognosis. RESULTS: The correlation between patient prognosis and clinicopathological factors, mutational status, or mRNA level changes was examined. Univariate (p = 0.0007) and subsequent multivariate analyses on clinicopathological factors showed that location (left or right) was the only independent risk factor for patient prognosis (HR = 3.63; 95% CI: 1.56-8.40, p = 0.003), while T, N, M staging, gender, race, location (rectum or colon), and pathological types were not stratifying factors. The mutational status of APC, TP53, KRAS, TTN, SYNE1, SMAD4, PIK3CA, RYR2, and BRAF did not show significant stratification in patient prognosis. RNA-seq showed that genes related to membrane function, ion channels, transporters, or receptors were among those with significant mRNA level alterations. Univariate analysis identified 97 genes with significantly altered mRNA levels, while NEUROD1, FGF18, SFTA2, PLAC1, SAA2, DSCAML1, and OTOP3 were significant in multivariate analysis. A risk model was established to stratify the prognosis of stage IV CRC patients. A Nomogram model was established with these genes to predict individual patient prognosis. CONCLUSIONS: A panel of eight genes with significant mRNA level alterations was capable of predicting the prognosis and risk of the specific patient group. Future prospective study is needed to validate the model.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , ARN Mensajero , Humanos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Neoplasias Hepáticas/secundario , Mutación , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , ARN Mensajero/genética
5.
Front Genet ; 13: 860669, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35401688

RESUMEN

Beijing Black pig is an excellent cultivated black pig breed in China, with desirable body shape, tender meat quality and robust disease resistance. To explore the level of admixture and selection signatures of Beijing Black pigs, a total number of 90 individuals covering nine pig breeds were used in our study, including Beijing Black pig, Large White, Landrace, Duroc, Lantang pig, Luchuan pig, Mashen pig, Huainan pig and Min pig. These animals were resequenced with 18.19 folds mapped read depth on average. Generally, we found that Beijing Black pig was genetically closer to commercial pig breeds by population genetic structure and genetic diversity analysis, and was also affected by Chinese domestic breeds Huainan pig and Min pig. These results are consistent with the cross-breeding history of Beijing Black pig. Selection signal detections were performed on three pig breeds, Beijing Black pig, Duroc and Large White, using three complementary methods (FST, θπ, and XP-EHH). In total, 1,167 significant selected regions and 392 candidate genes were identified. Functional annotations were enriched to pathways related to immune processes and meat and lipid metabolism. Finally, potential candidate genes, influencing meat quality (GPHA2, EHD1, HNF1A, C12orf43, GLTP, TRPV4, MVK, and MMAB), reproduction (PPP2R5B and MAP9), and disease resistance (OASL, ANKRD13A, and GIT2), were further detected by gene annotation analysis. Our results advanced the understanding of the genetic mechanism behind artificial selection of Beijing Black pigs, and provided theoretical basis for the subsequent breeding and genetic research of this breed.

6.
J Bone Miner Metab ; 40(3): 389-401, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35333985

RESUMEN

INTRODUCTION: A disintegrin and metallopeptidase with thrombospondin type 1 motif 6 (ADAMTS6)-derived circular RNA (circADAMTS6; hsa_circ_0008667) is a novel regulator in interleukin (IL)-1ß-induced apoptosis of human chondrocytes (HCs). Here, we planned to probe into its role and mechanism underlying HCs injury in osteoarthritis. MATERIALS AND METHODS: Real time-quantitative PCR and immunoblotting estimated the abundance of RNA and protein, respectively. Cell proliferation and apoptosis were measured by WST-8, EdU, fluorescein isothiocyanate, and caspase3/7 activity assays. Levels of inflammatory cytokines (IL-6 and tumor necrosis factor-α), apoptosis-related proteins (Bcl-2 and Bcl-2-associated X protein), extracellular matrix (ECM)-related proteins (matrix metalloproteinase-13 and collagen type II alpha-1), and PI3K/AKT/mTOR signaling pathway-related proteins (AKT, mTOR, phosphorylated-AKT, and phosphorylated-mTOR) were evaluated by enzyme-linked immunosorbent assays and immunoblotting. Target relationship was confirmed by dual-luciferase reporter, Argonaute-2 immunoprecipitation and RNA pull-down assays. RESULTS: Abundances of circADAMTS6 and phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3) were underexpressed, and microRNA (miR)-324-5p was elevated in human osteoarthritic tissues and IL-1ß-induced HCs. Overexpressing circADAMTS6 and inhibiting miR-324-5p enhanced proliferation and ECM synthesis, but suppressed apoptosis and inflammatory response in IL-1ß-challenged HCs. Besides, silencing circADAMTS6 caused similar effects of IL-1ß stress on HCs. Mechanically, there was a direct interaction between miR-324-5p and circADAMTS6 or PIK3R3, and IL-1ß-induced activation of PI3K/AKT/mTOR signaling pathway was suppressed by circADAMTS6 overexpression and miR-324-5p silencing. Furthermore, counteractive effects of miR-324-5p upregulation on circADAMTS6 overexpression and PIK3R3 knockdown on miR-324-5p silencing were observed. CONCLUSION: CircADAMTS6-miR-324-5p-PIK3R3 axis might participate in IL-1ß-induced HCs dysfunction via competing endogenous RNA mechanism and the PI3K/AKT/mTOR signaling pathway.


Asunto(s)
Condrocitos , MicroARNs , Fosfatidilinositol 3-Quinasas , ARN Circular , Apoptosis/genética , Condrocitos/metabolismo , Condrocitos/patología , Humanos , Interleucina-1beta/administración & dosificación , MicroARNs/genética , MicroARNs/metabolismo , Osteoartritis/genética , Osteoartritis/metabolismo , Osteoartritis/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/farmacología
7.
Ann Thorac Surg ; 108(2): e73-e75, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30763556

RESUMEN

Impending paradoxical embolism (IPDE) is the presence of a thrombus in the patent foramen ovale. Usually, IPDE is diagnosed by echocardiography or a multislice computed tomography scan and is performed during the evaluation of a patient presenting with suspected pulmonary embolism. We report 2 patients who presented with IPDE and were successfully treated with cardiac surgery and thrombolytic therapy. Thus, we focus our discussion on the diagnosis and treatment modalities of this rare entity.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/métodos , Embolia Paradójica/cirugía , Foramen Oval Permeable/complicaciones , Embolia Pulmonar/cirugía , Ecocardiografía Transesofágica , Embolia Paradójica/diagnóstico , Embolia Paradójica/etiología , Femenino , Foramen Oval Permeable/diagnóstico , Foramen Oval Permeable/cirugía , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector/métodos , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/etiología
8.
Exp Ther Med ; 14(5): 5057-5062, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29201214

RESUMEN

Osteoarthritis (OA) has become a major public health problem with the increased aging population. Previous studies have demonstrated that resveratrol (RES) was able to increase the level of sirtuin 1 (Sirt1) in OA chondrocytes. However, further investigations are required to elucidate the precise molecular mechanism of RES and the potential link between Sirt1 and RES. Therefore, the present study used 30 clinical OA chondrocyte to examine chondrocyte viability, apoptosis rate and the mRNA and protein expression levels of Sirt1 and relevant genes implicated in apoptosis, extracellular matrix (ECM) degradation and Wnt/ß-catenin signaling pathway. RES and nicotinamide were used as the stimulus and inhibitor, respectively. The results demonstrated that the apoptotic rate reduced as the cell population decreased from 13.83 to 6.55% in response to 10 µM RES. Expression levels of B-cell lymphoma 2 (Bcl-2) associated X protein (Bax), procaspase-3 and -9, matrix metalloproteinase 1 (MMP1), MMP3, MMP13, Wnt3a, Wnt5a, Wnt7a and ß-catenin were significantly inhibited (P<0.01), whereas the level of Bcl-2 was significantly increased (P<0.01) in OA chondrocytes treated with 10 µM RES. These observations suggested that Sirt1 may regulate apoptosis and ECM degradation in RES-treated osteoarthritis chondrocytes via the Wnt/ß-catenin signaling pathway.

9.
Toxins (Basel) ; 9(1)2017 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-28098812

RESUMEN

Food and feed contamination by aflatoxin (AF)B1 has adverse economic and health consequences. AFB1 degradation by microorganisms or microbial enzymes provides a promising preventive measure. To this end, the present study tested 43 bacterial isolates collected from maize, rice, and soil samples for AFB1-reducing activity. The higher activity was detected in isolate L7, which was identified as Bacillus shackletonii. L7 reduced AFB1, AFB2, and AFM1 levels by 92.1%, 84.1%, and 90.4%, respectively, after 72 h at 37 °C. The L7 culture supernatant degraded more AFB1 than viable cells and cell extracts; and the degradation activity was reduced from 77.9% to 15.3% in the presence of proteinase K and sodium dodecyl sulphate. A thermostable enzyme purified from the boiled supernatant was designated as Bacillus aflatoxin-degrading enzyme (BADE). An overall 9.55-fold purification of BADE with a recovery of 39.92% and an activity of 3.85 × 10³ U·mg-1 was obtained using chromatography on DEAE-Sepharose. BADE had an estimated molecular mass of 22 kDa and exhibited the highest activity at 70 °C and pH 8.0, which was enhanced by Cu2+ and inhibited by Zn2+, Mn2+, Mg2+, and Li⁺. BADE is the major protein involved in AFB1 detoxification. This is the first report of a BADE isolated from B. shackletonii, which has potential applications in the detoxification of aflatoxins during food and feed processing.


Asunto(s)
Aflatoxina B1/metabolismo , Aflatoxina M1/metabolismo , Aflatoxinas/metabolismo , Bacillus/enzimología , Proteínas Bacterianas/metabolismo , Bacillus/clasificación , Proteínas Bacterianas/química , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Inactivación Metabólica , Metales/química , Especificidad por Sustrato , Temperatura , Factores de Tiempo
10.
Int J Biol Sci ; 11(12): 1376-89, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26681917

RESUMEN

The failure of reproductive success in polycystic ovary syndrome (PCOS) patients could be in part due to endometrial dysfunction. However, no studies have investigated any causality between androgen, androgen receptor (AR) expression, and adenosine monophosphate activated protein kinase (AMPK) activation in the endometrium under physiological and pathological conditions. In the present study, we show that 1) endometrial AR expression levels fluctuate in non-PCOS and PCOS patients during the menstrual cycle; 2) the menstrual phase-dependent alteration of p-AMPKα expression occurs in non-PCOS patients but not in PCOS patients; 3) AR expression is higher in PCOS patients than non-PCOS patients during hyperplasia while AMPKα activation (indicated by the ratio of p-AMPKα to AMPKα); and 4) co-localization of AR and Ki-67 in epithelial cell nuclei is observed in endometrial hyperplasia. Importantly, using in vitro human tissue culture and an in vivo 5α-dihydrotestosterone-treated rat model, we show that the action of androgen on AMPKα activation is likely mediated through nuclear AR, especially in epithelial cells. Collectively, we present evidence that AR expression and AMPKα activation depend on menstrual cycle phase and the presence of PCOS, and the data suggest that AR-mediated regulation of AMPKα activation might play a role in the development of endometrial hyperplasia.


Asunto(s)
Adenilato Quinasa/metabolismo , Endometrio/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Receptores Androgénicos/metabolismo , Animales , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Dihidrotestosterona/farmacología , Endometrio/enzimología , Femenino , Flutamida/farmacología , Humanos , Técnicas In Vitro , Antígeno Ki-67/metabolismo , Fosforilación , Síndrome del Ovario Poliquístico/enzimología , Ratas , Ratas Wistar
11.
Sensors (Basel) ; 15(8): 20086-96, 2015 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-26287205

RESUMEN

Ag-modified In2O3/ZnO bundles with micro/nano porous structures have been designed and synthesized with by hydrothermal method continuing with dehydration process. Each bundle consists of nanoparticles, where nanogaps of 10-30 nm are present between the nanoparticles, leading to a porous structure. This porous structure brings high surface area and fast gas diffusion, enhancing the gas sensitivity. Consequently, the HCHO gas-sensing performance of the Ag-modified In2O3/ZnO bundles have been tested, with the formaldehyde-detection limit of 100 ppb (parts per billion) and the response and recover times as short as 6 s and 3 s, respectively, at 300 °C and the detection limit of 100 ppb, response time of 12 s and recover times of 6 s at 100 °C. The HCHO sensing detect limitation matches the health standard limitation on the concentration of formaldehyde for indoor air. Moreover, the strategy to synthesize the nanobundles is just two-step heating and easy to scale up. Therefore, the Ag-modified In2O3/ZnO bundles are ready for industrialization and practical applications.


Asunto(s)
Electrónica/instrumentación , Formaldehído/análisis , Gases/análisis , Indio/química , Nanopartículas/química , Plata/química , Óxido de Zinc/química , Nanopartículas/ultraestructura , Nitrógeno/química , Espectrometría por Rayos X , Temperatura
12.
Phys Chem Chem Phys ; 17(11): 7248-54, 2015 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-25692228

RESUMEN

The highest occupied molecular orbital (HOMO) energies of carbon nanotubes (CNTs) and graphene are crucial in fundamental and applied research of carbon nanomaterials, and so their modulation is desired. Our first-principles calculations reveal that the HOMO energies of CNTs and graphene can both be raised by negatively charging, and that the rate of increase of the HOMO energy of a CNT is much greater and faster than that of graphene with the same number of C atoms. This discriminative modulation holds true regardless of the number of C atoms and the CNT type, and so is universal. This work provides a new opportunity to develop all-carbon devices with CNTs and graphene as different functional elements.

13.
Nature ; 501(7468): E1, 2013 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-24067718
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