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1.
BMC Gastroenterol ; 24(1): 83, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395771

RESUMEN

OBJECTIVE: Acute mesenteric vein thrombosis (AMVT) is an acute abdominal disease with onset, rapid progression, and extensive intestinal necrosis that requires immediate surgical resection. The purpose of this study was to determine the risk factors for nosocomial intestinal resection in patients with AMVT. METHODS: We retrospectively analysed 64 patients with AMVT diagnosed by CTA at the Affiliated Hospital of Kunming University of Science and Technology from January 2013 to December 2021. We compared patients who underwent intestinal resection (42 patients) with those who did not undergo intestinal resection (22 patients). The area under the ROC curve was evaluated, and a forest map was drawn. RESULTS: Among the 64 patients, 6 (9.38%) had a fever, 60 (93.75%) had abdominal pain, 9 (14.06%) had a history of diabetes, 8 (12.5%) had a history of deep vein thrombosis (DVT), and 25 (39.06%) had ascites suggested by B ultrasound or CT after admission. The mean age of all patients was 49.86 ± 16.25 years. The mean age of the patients in the enterectomy group was 47.71 ± 16.20 years. The mean age of the patients in the conservative treatment group (without enterectomy) was 53.95 ± 15.90 years. In the univariate analysis, there were statistically significant differences in leukocyte count (P = 0.003), neutrophil count (P = 0.001), AST (P = 0.048), total bilirubin (P = 0.047), fibrinogen (P = 0.022) and DD2 (P = 0.024) between the two groups. The multivariate logistic regression analysis showed that admission white blood cell count (OR = 1.153, 95% CI: 1.039-1.280, P = 0.007) was an independent risk factor for intestinal resection in patients with AMVT. The ROC curve showed that the white blood cell count (AUC = 0.759 95% CI: 0.620-0.897; P = 0.001; optimal threshold: 7.815; sensitivity: 0.881; specificity: 0.636) had good predictive value for emergency enterectomy for AMVT. CONCLUSIONS: Among patients with AMVT, patients with a higher white blood cell count at admission were more likely to have intestinal necrosis and require emergency enterectomy. This study is helpful for clinicians to accurately determine whether emergency intestinal resection is needed in patients with AMVT after admission, prevent further intestinal necrosis, and improve the prognosis of patients.


Asunto(s)
Isquemia Mesentérica , Trombosis , Humanos , Adulto , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Venas Mesentéricas/cirugía , Enfermedad Aguda , Pronóstico , Isquemia Mesentérica/cirugía , Recuento de Leucocitos , Trombosis/complicaciones , Necrosis , Curva ROC
2.
BMC Surg ; 24(1): 305, 2024 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-39396012

RESUMEN

BACKGROUND: Acute hepatic dysfunction (AHD) is a common postoperative complication in patients with acute type A aortic dissection. The aim of this study was to identify risk factors for acute hepatic dysfunction after surgery for acute type A aortic dissection. METHODS: We performed a retrospective study from March 1, 2019, to February 28, 2021. The primary endpoints of this study were morbidity due to AHD and risk factors for incidence. Univariate analysis and multivariate logistic regression analysis were used to analyse the related factors, and receiver operating characteristic (ROC) curves were plotted to evaluate their predictive value. RESULTS: Among 147 patients, 29 (19.73%) developed postoperative acute hepatic dysfunction, and 9 (6.12%) died. Univariate analysis revealed that the ALT (P = 0.042), Cr (P < 0.001), and BUN (P = 0.008) levels were significantly different between the two groups. Multivariate logistic regression analysis revealed that Cr (OR = 1.013, 95% CI = 1.003-1.023, P = 0.008) was an independent risk factor for postoperative hepatic dysfunction in overweight (BMI > 24) patients with ATAAD. The area under the ROC curve (AUC) for Cr was 0.745 > 0.7, indicating good predictive value. CONCLUSION: A high Cr concentration is an independent risk factor for postoperative AHD in overweight (BMI > 24) patients with ATAAD.


Asunto(s)
Disección Aórtica , Sobrepeso , Complicaciones Posoperatorias , Humanos , Masculino , Disección Aórtica/cirugía , Disección Aórtica/complicaciones , Femenino , Factores de Riesgo , Estudios Retrospectivos , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/diagnóstico , Sobrepeso/complicaciones , Anciano , Hepatopatías/complicaciones , Curva ROC , Adulto , Incidencia , Enfermedad Aguda
3.
Angew Chem Int Ed Engl ; : e202418176, 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39402870

RESUMEN

The regulation of interfaces remains a critical and challenging aspect in the pursuit of highly efficient and stable perovskite solar cells (PSCs). Here, 2,2'-bipyridyl-4,4'-dicarboxylic acid (HBPDC) is incorporated as an interfacial layer between SnO2 and perovskite layers in PSCs. The two carboxylic acid moieties on HBPDC bind to SnO2 through esterification, while its nitrogen atoms, possessing lone electron pairs, interact with uncoordinated lead (Pb2+) atoms through Lewis acid-base interactions. This dual functionality enables simultaneous passivation of surface defects on both the SnO2 and buried perovskite layers. In addition, the electron-deficient nature of HBPDC enhances interfacial energy band alignment and facilitates electron transfer from the perovskite to SnO2. Furthermore, the incorporation of HBPDC strengthens the interfacial adhesion, improving mechanical reliability. As a result, the PSCs exhibited an impressive power conversion efficiency (PCE) of 25.41% under standard AM 1.5G conditions, along with remarkable environmental stability.

4.
Cerebrovasc Dis ; 52(4): 363-375, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36423584

RESUMEN

INTRODUCTION: This meta-analysis assessed the predictors of symptomatic intracranial hemorrhage (sICH) after endovascular thrombectomy (EVT) for patients with acute ischemic stroke. METHODS: PubMed, Embase, the Cochrane Central Register of Controlled Trials, and Web of Science were searched for studies published from inception to February 16, 2021. We included studies that evaluated the predictors of sICH after EVT. The random-effect model or fixed-effect model was used to pool the estimates according to the heterogeneity. RESULTS: A total of 25 cohort studies, involving 15,324 patients, were included in this meta-analysis. The total incidence of sICH was 6.72 percent. Age (MD = 2.57, 95% CI: 1.53-3.61; p < 0.00001), higher initial NIHSS score (MD = 1.71, 95% CI: 1.35-2.08, p < 0.00001), higher initial systolic blood pressure (MD = 7.40, 95% CI: 5.11-9.69, p < 0.00001), diabetes mellitus (OR = 1.36, 95% CI: 1.10-1.69, p = 0.005), poor collaterals (OR = 3.26, 95% CI: 2.35-4.51; p < 0.0001), internal carotid artery occlusion (OR = 1.55, 95% CI: 1.26-1.90; p < 0.0001), longer procedure time (MD = 18.92, 95% CI: 11.49-26.35; p < 0.0001), and passes of retriever >3 (OR = 3.39, 95% CI: 2.45-4.71; p < 0.0001) were predictors of sICH, while modified thrombolysis in cerebral infarction score ≥2b (OR = 0.61, 95% CI: 0.46-0.79; p = 0.0002) was associated with a decreased risk of sICH. There were no significant differences in the female gender, initial serum glucose, initial ASPECT score, atrial fibrillation, oral anticoagulants, antiplatelet therapy, intravenous thrombolysis, general anesthesia, neutrophil-to-lymphocyte ratio, and emergent stenting. CONCLUSIONS: This study identified many predictors of sICH. Some of the results lack robust evidence given the limitations of the study. Therefore, larger cohort studies are needed to confirm these predictors.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Femenino , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/terapia , Accidente Cerebrovascular Isquémico/complicaciones , Hemorragias Intracraneales/diagnóstico por imagen , Hemorragias Intracraneales/epidemiología , Trombectomía/efectos adversos , Trombectomía/métodos , Estudios de Cohortes
5.
Phys Chem Chem Phys ; 25(33): 22002-22010, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37555282

RESUMEN

Understanding the functional group modulation of electronic structure and excitation is pivotal to the design of organic small molecules (OSMs) for photoelectric applications. In this study, we employed density functional theory (DFT) and time-dependent DFT (TDDFT) calculations to explore the unique absorption character of four triphenylamine photosensitizers. The various conformations were investigated given the multiple single bonds in the compounds, and the resemblance in the electronic structure of different conformations is affirmed because the coplanarity and consequent long-range conjugation is maintained regardless of the orientation of the flexible blocks. Six functionals were evaluated, and MN15 was found to successfully reproduce the intense secondary absorption peak for the double 3,4-ethylenedioxythiophene (EDOT) modified sensitizer over B3LYP, PBE0, M062X, CAM-B3LYP, and ωB97XD. The introduction of EDOT gives rise to a new excited state S4, which is a local excitation constrained in the EDOT substituent triphenylamine block. This new excited state S4, in combination with inherent S2 and S3 derived from prototype molecule TPA-Pyc, jointly contributes to the hump of the secondary absorption peak of ETE-Pyc and finally affects the light-harvesting ability of the dye-sensitized TiO2 photoanode. The current findings provide guidance toward the rational design of OSMs with good light-harvest ability.

6.
Acc Chem Res ; 54(8): 1961-1971, 2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33599477

RESUMEN

Syngas conversion is a key platform for efficient utilization of various carbon-containing resources including coal, natural gas, biomass, organic wastes, and even CO2. One of the most classic routes for syngas conversion is Fischer-Tropsch synthesis (FTS), which is already available for commercial application. However, it still remains a grand challenge to tune the product distribution from paraffins to value-added chemicals such as olefins and higher alcohols. Breaking the selectivity limitation of the Anderson-Schulz-Flory (ASF) distribution has been one of the hottest topics in syngas chemistry.Metallic Co0 is a well-known active phase for Co-catalyzed FTS, and the products are dominated by paraffins with a small amount of chemicals (i.e., olefins or alcohols). Specifically, a cobalt carbide (Co2C) phase is typically viewed as an undesirable compound that could lead to deactivation with low activity and high methane selectivity. Although iron carbide (FexC) can produce olefins with selectivity up to ∼60%, the fraction of methane is still rather high, and the required high reaction temperature (300-350 °C) typically causes coke deposition and fast deactivation. Recently, we discovered that Co2C nanoprisms with preferentially exposed facets of (020) and (101) can effectively produce olefins from syngas conversion under mild reaction conditions with high selectivity. The methane fraction was limited within 5%, and the product distribution deviated greatly from ASF statistic law. The catalytic performances of Co2C nanoprisms are completely different from that reported for the traditional FT process, exhibiting promising potential industrial application.This Account summarizes our progress in the development of Co2C nanoprisms for Fischer-Tropsch synthesis to olefins (FTO) with remarkable efficiencies and stability. The underlying mechanism for the observed unique catalytic behaviors was extensively explored by combining DFT calculation, kinetic measurements, and various spectroscopic and microscopic investigation. We also emphasize the following issues: particle size effect of Co2C, the promotional effect of alkali and Mn promoters, and the role of metal-support interaction (SMI) in fabricating supported Co2C nanoprisms. Specially, we briefly review the synthetic methods for different Co2C nanostructures. In addition, Co2C can also be applied as a nondissociative adsorption center for higher alcohol synthesis (HAS) via syngas conversion. We also discuss the construction of a Co0/Co2C interfacial catalyst for HAS and demonstrate how to tune the reaction network and strengthen CO nondissociative adsorption ability for efficient production of higher alcohols. We believe that the advances in the development of Co2C nanocatalysts described here present a critic step to produce chemicals through the FTS process.

7.
J Craniofac Surg ; 32(2): 603-608, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33704991

RESUMEN

ABSTRACT: Osteoporosis as a kind of systemic bone metabolic disease has become one of the most prevalent diseases among the middle- and old-age, characterized with low bone mass and disruptive osseous microenvironment. The poor bone condition both in quantity and quality makes it daunting for osteoporotic patients who are submitted to dental implantation, joint replacement therapy, or orthopedic surgery. Since calcium phosphate (CaP) and platelet-rich plasma (PRP) treatment, all have improving the effect on bone regeneration. Inspired by this fact, the authors introduced a kind of novel implant with CaP modified surface by HPT (hydrothermal & pressure) treatment in this study. After producing, the authors tested its physicochemical properties through scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscope (XPS) and contact-angle measurement. Then the authors desired to investigate the effect of this CaP-modified implant on bone regeneration and stabilization maintenance combined with PRP treatment by establishing an osteoporotic rat model. After 3 months of surgery, the authors collected all the specimens and evaluated new bone formation by micro-computed tomography (micro-CT) analysis, biomechanical test, and histologic assessment. All the results in vivo experiment showed the CaP modified implant combined with PRP treatment could improve the osteoinductive effect under osteoporotic condition, leading to better maintenance for stabilization between bone and implant interface, which might be rendered as a promising clinical method for osteoporotic patients when they receive orthopedic surgeries.


Asunto(s)
Implantes Dentales , Plasma Rico en Plaquetas , Animales , Fosfatos de Calcio , Humanos , Oseointegración , Ratas , Titanio , Microtomografía por Rayos X
8.
Cardiovasc Ultrasound ; 18(1): 5, 2020 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-32005178

RESUMEN

BACKGROUND: Mitral regurgitation volume (MRvol) by quantitative pulsed Doppler (QPD) method previously recommended suffers from geometric assumption error because of circular geometric assumption of mitral annulus (MA). Therefore, the aim of this study was to evaluate the impact of different geometric assumption of MA on the assessment of MRvol by two-dimensional transthoracic echocardiographic QPD method. METHODS: This study included 88 patients with varying degrees of mitral regurgitation (MR). The MRvol was evaluated by QPD method using circular or ellipse geometric assumption of MA. MRvol derived from effective regurgitant orifice area by real time three-dimensional echocardiography (RT3DE) multiplied by MR velocity-time integral was used as reference method. RESULTS: Assumption of a circular geometry of MA, QPD-MAA4C and QPD-MAPLAX overestimated the MRvol by a mean difference of 10.4 ml (P < 0.0001) and 22.5 ml (P < 0.0001) compared with RT3DE. Assumption of an ellipse geometry of MA, there was no significant difference of MRvol (mean difference = 1.7 ml, P = 0.0844) between the QPD-MAA4C + A2C and the RT3DE. CONCLUSIONS: Assuming that the MA was circular geometry previously recommended, the MRvol by QPD-MAA4C was overestimated compared with the reference method. However, assuming that the MA was ellipse geometry, the MRvol by the QPD-MAA4C + A2C has no significant difference with the reference method.


Asunto(s)
Velocidad del Flujo Sanguíneo/fisiología , Ecocardiografía Doppler de Pulso/métodos , Ecocardiografía Tridimensional/métodos , Ventrículos Cardíacos/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/diagnóstico , Válvula Mitral/diagnóstico por imagen , Femenino , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/fisiopatología
9.
J Craniofac Surg ; 31(2): 416-419, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31764552

RESUMEN

In this study, nonmineralized silk fibroin/gelatin (SF/G) hybrid scaffolds and the mineralized SF/G/hydroxyapatite (SF/G/HA) hybrid scaffolds were fabricated using vacuum freeze-drying method and biomineralization technique. The morphology and mechanical properties of the 2 hybrid scaffolds were characterized. Furthermore, the cytotoxic profiles of the hybrid scaffolds were investigated in vitro by seeding the human osteoblast cells (hFOB1.19). The 2 hybrid scaffolds were both highly porous and the pore sizes of the SF/G as well as SF/G/HA hybrid scaffolds were 260 ±â€Š58 µm and 210 ±â€Š35 µm, respectively. Compared with the SF/G hybrid scaffold, the SF/G/HA hybrid scaffolds exhibited significantly enhanced compressive strength and modulus. Significant early cell adhesion and proliferation on the SF/G hybrid scaffolds were observed, while SF/G/HA hybrid scaffolds effectively improved osteogenic differentiation of hFOB1.19 after 10 days of coculture. The results confirmed that the 2 hybrid scaffolds were both cytocompatible and had almost no negative effects on the hFOB1.19 in vitro. However, the SF/G/HA hybrid scaffolds tended to be more promising for application in bone-tissue engineering with good mechanical property and osteogenic differentiation.


Asunto(s)
Fibroínas , Gelatina , Ingeniería de Tejidos/métodos , Huesos/metabolismo , Adhesión Celular , Diferenciación Celular , Línea Celular , Proliferación Celular , Fuerza Compresiva , Humanos , Osteoblastos/metabolismo , Osteogénesis , Porosidad , Andamios del Tejido
10.
Med Sci Monit ; 24: 2218-2224, 2018 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-29652869

RESUMEN

BACKGROUND Previous studies have demonstrated that sustained hypoxia in people with obstructive sleep apnea (OSA) impairs upper airway muscle activity, but the underlying mechanism remains poorly understood. As autophagy acts as an important regulator under hypoxia stress, we performed an in vitro investigation of the effects of sustained hypoxia on autophagy of genioglossus muscle-derived stem cells (GG MDSC), an important component of the upper airway muscle. MATERIAL AND METHODS Genioglossus MDSCs were obtained from Sprague-Dawley (SD) rats and identified by using immunofluorescence staining for CD34, Sca-1, and desmin. GG MDSCs were incubated under normoxic or sustained hypoxic conditions for different periods of time. Western blotting was used to detect LC3 and Beclin 1, which are 2 important proteins in autophagy flux, and autophagolysosomes accumulation was observed by transmission electron microscopy (TEM). The mRNA and protein levels of HIF-1α and BNIP3 were evaluated by RT-PCR and Western blot analysis, respectively. RESULTS Our study shows that sustained hypoxia promotes the expression of LC3BII and Beclin 1 in GG MDSCs in a time-dependent manner. TEM showed an increased number of autophagolysosomes in GG MDSCs under sustained hypoxia for 12 and 24 h. In addition, hypoxia activated the HIF-1α/BNIP3 signal pathway both at protein levels (shown by Western blot) and at mRNA levels (shown by RT-PCR). CONCLUSIONS Our study shows that sustained hypoxia promotes autophagy in GG MDSCs, and the HIF-1a/BNIP3 signal pathway was involved in this process.


Asunto(s)
Células Madre Adultas/fisiología , Autofagia/fisiología , Hipoxia/fisiopatología , Células Madre Adultas/metabolismo , Animales , Autofagia/genética , Beclina-1/genética , Beclina-1/metabolismo , Hipoxia de la Célula/genética , Mentón/cirugía , Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Masculino , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Músculo Esquelético/fisiología , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
11.
Cardiovasc Ultrasound ; 16(1): 32, 2018 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-30545377

RESUMEN

BACKGROUND AND OBJECTIVES: This study aimed to assess the changes of RA function in patients with obstructive sleep apnea syndrome (OSAS) using velocity vector imaging (VVI) and to evaluate the application of VVI technology. METHODS: According to the apnea-hypopnea index (AHI), 71 patients with OSAS were divided into three groups: mild, moderate, and severe. A total of 30 cases of healthy subjects were enrolled as the control group. Digital images of apex four-chamber views were acquired to measure the right atrium (RA) linear dimensions and volume parameters including RA longitudinal diameter (RAL), transverse diameter (RAT), RA maximum volume (Vmax), RA minimum volume (Vmin), right atrial volume before contraction (Vpre). Right atrial volume parameters were corrected by body surface area (VImax, VImin, VIpre). The total right atrial emptying fraction (RATEF), right atrial passive emptying fraction (RAPEF), right atrial active contraction emptying fraction (RAAEF) were calculated. The VVI data measuring right atrial global strain (RA-GLS), right atrial strain rate in ventricular systolic phase (RA-SRs), right atrial strain rate in ventricular early diastolic phase (RA-SRe), right atrial strain rate in ventricular late diastolic phase (RA-SRa). RESULTS: 1. RA linear dimensions and volume parameters in severe OSAS were higher than those of control group. RAPEF in severe group was lower than control group and mild OSAS group (t = 2.681, P = 0.021; t = 2.985, P = 0.011; respectively). RAAEF in OSAS moderate group was higher than that of control group (t = 3.006, P = 0.02), and without statistical difference (P > 0.05) in the severe OSAS group and the control group. 2. RA-GLS in moderate OSAS group was significantly lower than that of control group (t = 2.333, P = 0.040) and reduced more obvious in the severe OSAS group (vs control, t = 3.25, P = 0.008, vs mild; t = 3.011, P = 0.012; respectively). RA-SRe in moderate and severe OSAS groups were lower than control group (t = 2.466, P = 0.031; t = 3.547, P = 0.005; respectively). RA-SRs of OSAS in severe group was lower than that of control and mild groups (t = 3.665, P = 0.004; t = 3.204, P = 0.008; respectively). RA-SRa in severe OSAS group was lower than that of control group (t = 2.425, P = 0.034). 3. Multivariate regression analysis showed that RA-GLS and RA-SRe were independently correlated with AHI (t = - 2.738, P = 0.010; t = - 2.191, P = 0.036; respectively). CONCLUSION: RA function was impaired in patients with OSAS. On hemodynamics, the change of RA function performed increased of reserve function, reduced pipeline function and increased of contraction function. However, the strain and strain rate reduced in different degree. RA-GLS and RA-SRe decreased the earliest, which suggested that strain and strain rate were the parameters which can reflect myocardial function damage earliest. VVI can more earlier and accurately detect myocardial dysfunction of right atrium in patients with OSAS, which is expected to be a worthy technique for early clinical therapy in patients with OSAS.


Asunto(s)
Función del Atrio Derecho/fisiología , Atrios Cardíacos/fisiopatología , Flujometría por Láser-Doppler/métodos , Apnea Obstructiva del Sueño/diagnóstico por imagen , Adulto , Estudios de Casos y Controles , Ecocardiografía/métodos , Femenino , Atrios Cardíacos/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Polisomnografía/métodos , Valores de Referencia , Análisis de Regresión , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Apnea Obstructiva del Sueño/fisiopatología
12.
Cardiovasc Ultrasound ; 14(1): 45, 2016 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-27832782

RESUMEN

BACKGROUND: The myocardial wall of the left ventricle is a complex, multilayered structure and is not homogenous. The aim of this study was to determine longitudinal strain (LS) in the three myocardial layers in normal pregnant women according to gestation proceedings. METHODS: The advanced two-dimensional speckle tracking echocardiography (2D STE) was performed on 62 women during each pregnancy trimester and 6 to 9 weeks after delivery, while 30 age-matched, healthy, nonpregnant women served as controls. LS on endocardial, mid-myocardial and epicardial layers at 18 cardiac segments were measured. RESULTS: As gestation proceeded, all of layer-specific LS and global LS progressively decreased, which subsequently recovered postpartum (P < 0.05), and the LS gradient between inner and outer myocardium became greater, which reached its maximum in the late pregnancy. Peak systolic LS was the highest at endocardium and the lowest at epicardium, while the highest at the apical level and the lowest at the base (P < 0.05). In the early pregnancy and postpartum, LS at basal level was homogenous, meanwhile layer-specific LS showed significant differences at mid-ventricular and apical level throughout the progress of normal pregnancy (P < 0.05). CONCLUSIONS: Using 2D STE, three-layer assessment of LS can be performed in pregnant women and shall give us new insights into the quantitative analysis of global and regional LV function during pregnancy. Future studies on the detection of pregnancy related heart disease would require these parameters as reference values for each time point of a normal pregnancy.


Asunto(s)
Ecocardiografía/métodos , Ventrículos Cardíacos/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Adulto , China , Femenino , Humanos , Embarazo , Función Ventricular Izquierda , Adulto Joven
13.
Polymers (Basel) ; 16(18)2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39339140

RESUMEN

Carbon Fiber Reinforced Polymer (CFRP) can be used to reinforce steel structures depending on its high strength and lightweight resistance. To analyze and evaluate the load-carrying capacity of CFRP-reinforced steel structures. This study uses the Finite Element Analysis (FEA) and the experimental tests combined to investigate the influence that the reinforcement patterns and the relevant parameters have on the load-carrying capacity. We made specimens with different reinforcement patterns. Take the steel beam specimen with full reinforcement as an example. Compared with the load-carrying capacity of the steel beam reinforced by two-layer CFRP cloth, that respectively increases by 5.16% and 11.1% when the number of the CFRP cloth increases to four and six, respectively. Based on a specimen set consisting of CFRP-reinforced steel structures under different reinforcement patterns, the random forest algorithm is used to develop an evaluation model for the load carrying. The performance test results show that the MAE (Mean Absolute Error) of the evaluation model can reach 0.12 and the RMSE (Root Mean Square Error) is 0.25, presenting a good prediction accuracy, which lays a solid foundation for the research on the CFRP-based reinforcement technology and process.

14.
J Cardiothorac Surg ; 18(1): 115, 2023 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-37031171

RESUMEN

OBJECTIVE: To analyze the clinical characteristics of patients with overweight acute type A aortic dissection, and to explore the risk factors of acute kidney injury in patients with overweight acute type A aortic dissection. METHODS: From March 2019 to February 2022, the clinical data of 71 patients with acute type a aortic dissection diagnosed by CTA and undergoing surgical treatment with BMI > 24 in the First People's Hospital of Yunnan Province were retrospectively analyzed, and analyzed by univariate and logistic multivariate analysis methods. RESULTS: The mean BMI of all included patients was 27.23, The mean surface area of all included human populations was 1.833. The mean age of all patients was (52.06 ± 10.71) years old, and 35 patients developed acute kidney injury after surgery. Multi-factor Logistics regression analysis confirmed the risk factors for postoperative acute kidney injury in overweight patients with acute type A aortic dissection, including gender, CPB transit time and intraoperative infusion of suspended red blood cells. Seven patients in the AKI group died in hospital after surgery and two patients died in the non-AKI group. CONCLUSIONS: Among patients with overweight acute Type A aortic dissection, the incidence of AKI is 49.30%. According to multi-factor Logistics regression analysis, gender, CPB transit time and intraoperative suspended red blood cell volume are independent risk factors for postoperative acute kidney injury in patients with overweight acute Type A aortic dissection.


Asunto(s)
Lesión Renal Aguda , Disección Aórtica , Humanos , Adulto , Persona de Mediana Edad , Estudios Retrospectivos , Sobrepeso/complicaciones , China/epidemiología , Disección Aórtica/complicaciones , Disección Aórtica/cirugía , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/etiología , Lesión Renal Aguda/terapia , Factores de Riesgo , Complicaciones Posoperatorias/epidemiología
15.
Technol Cancer Res Treat ; 22: 15330338231212073, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37920989

RESUMEN

Background: Endoplasmic reticulum (ER) stress plays a pro-apoptotic role in colorectal adenocarcinoma (COAD). This study aimed to develop a novel ER-stress-related prognostic risk model for COAD and provide support for COAD cohorts with different risk score responses to immune checkpoint inhibitor therapies. Methods: TCGA-COAD and GSE39582 were included in this prospective study. Univariate and multivariate Cox analyses were performed to identify prognostic ER stress-related genes (ERSGs). Accordingly, the immune infiltration landscape and immunotherapy response in different risk groups were assessed. Finally, the expression of prognostic genes in 10 normal and 10 COAD tissue samples was verified using reverse transcription-quantitative polymerase chain reaction. Results: Eight prognostic genes were selected to establish an ERSG-based signature in the training set of the TCGA-COAD cohort. The accuracy of this was confirmed using a testing set of TCGA-COAD and GSE39582 cohorts. Gene set variation analysis indicated that differential functionality in high-low-risk groups was related to immune-related pathways. Corresponding to this, CD36, TIMP1, and PTGIS were significantly associated with 19 immune cells with distinct proportions between the different risk groups, such as central memory CD4T cells and central memory CD8T cells. Moreover, the risk score was considered effective for predicting the clinical response to immunotherapy, and the immunotherapy response was significantly and negatively correlated with the risk score of individuals with COAD. Furthermore, the immune checkpoint inhibitor treatment was less effective in the high-risk group, where the expression levels of PD-L1 and tumor immune dysfunction and exclusion scores in the high-risk group were significantly increased. Finally, the experimental results demonstrated that the expression trends of prognostic genes in clinical samples were consistent with the results from public databases. Conclusion: Our study established a novel risk signature to predict the COAD prognosis of patients and provide theoretical support for the clinical treatment of COAD.


Asunto(s)
Adenocarcinoma , Neoplasias Colorrectales , Humanos , Pronóstico , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Estudios Prospectivos , Inmunoterapia , Adenocarcinoma/genética , Adenocarcinoma/terapia , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/terapia
16.
Zhonghua Wai Ke Za Zhi ; 50(1): 15-8, 2012 Jan 01.
Artículo en Zh | MEDLINE | ID: mdl-22490283

RESUMEN

OBJECTIVE: To investigate the indications, safety and efficacy of catheter directed thrombolysis for early left lower extremity deep venous thrombosis (DVT) without vena cava filters protection. METHODS: Clinical data of 54 cases of early left lower extremity DVT received catheter directed thrombolysis without vena cava filters from July 2008 to June 2010 were retrospectively analyzed. The thrombosis was entire without free floating clots and no thrombosis in vena cava detected with ultrasound scan. Twenty-five patients were male and 29 were female with the average age of 52.8 years. Fifty-one of which were iliofemoral and popliteal, the other 3 were iliofemoral. The course were ≤ 7 d in 45 cases and these were 8 to 30 d in 9 cases. Urokinase of 300 000 U was infused through catheters per 2 h twice a day. Meanwhile 4000 U of low weight heparin was administered subcutaneously per 12 h, or heparin infusion at dosage of 18 U×kg(-1)×h(-1). RESULTS: The procedure technically succeeded in all patients. In total cases venous score decreased to 4.6 ± 2.1 post 6 to 10 d of thrombolysis from 10.8 ± 1.0 with thrombolysis rate of 58% ± 18% which was not significantly different between groups of ≤ 7 d and 8 to 30 d (t = 1.02, P = 0.34). On 14(th) day, 11 patients (20.4%) completely recovered, 35 cases (64.8%) experienced large improvement, 8 patients (14.8%) had mild improvement and nobody was failed, resulting in total efficacy of 100%. No patient developed clinical symptomatic pulmonary embolism. SpO2 did not alter markedly post thrombolysis [(91.0 ± 2.6)% vs. (90.8 ± 2.4)%, t = 2.03, P = 0.05]. No patients suffered from cerebral hemorrhage and haemoturia, and catheter induced inflammation occurred in 4 cases (7.41%). There was mild bleeding in puncture sites in 11 patients (20.4%) during the course. There were 36 patients (66.7%) had been followed up with the time of 6 to 21 months. In which 31 cases had no lower extremity edema or had mild edema after activities. Two patients developed serious edema after activities for deep venous insufficiency. Three cases combined with malignant tumor or renal failure recurred. CONCLUSIONS: For early left extremity DVT which is entire without free floating clots and no thrombosis in vena cava, catheter directed thrombolysis without filter protection maybe administered with safety, efficiency and lower expense.


Asunto(s)
Cateterismo Periférico , Extremidad Inferior/irrigación sanguínea , Terapia Trombolítica/métodos , Trombosis de la Vena/terapia , Femenino , Fibrinolíticos/administración & dosificación , Fibrinolíticos/uso terapéutico , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Embolia Pulmonar/prevención & control , Estudios Retrospectivos , Activador de Plasminógeno de Tipo Uroquinasa/administración & dosificación , Activador de Plasminógeno de Tipo Uroquinasa/uso terapéutico , Filtros de Vena Cava , Trombosis de la Vena/complicaciones
17.
Proc Inst Mech Eng H ; 236(12): 1732-1743, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36285396

RESUMEN

The dental implant is challenging due to the unstable quality of the surrounding bone. This study aimed to explore the feasibility of using thrust force characteristics to identify different bone types and the influencing mechanisms of spindle speed and feed rate on primary stability of dental implants through in-vitro experiments. 13 groups of osteotomy experiments were performed on mandibles and maxillae of pigs with different bone types (I, II, and III) under different spindle speeds (600 and 800 rpm) and feed rates (20 and 60 mm/min). The thrust force evolution under different conditions was extracted and analysed to elaborate the distribution and thickness of the cortical and trabecular bone layers on different bone types. Dental implant placements were performed, and corresponding primary stabilities were obtained. Furthermore, histologic observation was conducted to reveal the bone/implant contact morphology. From the results, the amplitude and trend of thrust force show a regular variation during drilling different bone types. The highly dynamic information of thrust force can be analysed to characterise the distribution and thickness of the cortical and trabecular bone layers, hence effectively detecting different bone types. Since a lower feed rate and resulting bone temperature elevation lead to more thermal damages, primary stability decreases with the decrease of feed rate. Spindle speed has no significant effect. This study establishes a more in-depth understanding into the thrust force evolution and also provide a clinical option for reducing the complexity of bone type and drilling parameters determination in osteotomy.


Asunto(s)
Implantes Dentales , Porcinos , Animales , Fenómenos Mecánicos , Osteotomía , Mandíbula/cirugía , Implantación Dental
18.
Chem Commun (Camb) ; 58(70): 9712-9727, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-35972448

RESUMEN

Syngas conversion provides an important platform for efficient utilization of various carbon-containing resources such as coal, natural gas, biomass, solid waste and even CO2. Various value-added fuels and chemicals including paraffins, olefins and alcohols can be directly obtained from syngas conversion via the Fischer-Tropsch Synthesis (FTS) route. However, the product selectivity control still remains a grand challenge for FTS due to the limitation of Anderson-Schulz-Flory (ASF) distribution. Our previous works showed that, under moderate reaction conditions, Co2C nanoprisms with exposed (101) and (020) facets can directly convert syngas to olefins with low methane and high olefin selectivity, breaking the limitation of ASF. The application of Co2C-based nanocatalysts unlocks the potential of the Fischer-Tropsch process for producing olefins. In this feature article, we summarized the recent advances in developing highly efficient Co2C-based nanocatalysts and reaction pathways for direct syngas conversion to olefins via the Fischer-Tropsch to olefin (FTO) reaction. We mainly focused on the following aspects: the formation mechanism of Co2C, nanoeffects of Co2C-based FTO catalysts, morphology control of Co2C nanostructures, and the effects of promoters, supports and reactors on the catalytic performance. From the viewpoint of carbon utilization efficiency, we presented the recent efforts in decreasing the CO2 selectivity for FTO reactions. In addition, the attempt to expand the target products to aromatics by coupling Co2C-based FTO catalysts and H-ZSM-5 zeolites was also made. In the end, future prospects for Co2C-based nanocatalysts for selective syngas conversion were proposed.

19.
Med Eng Phys ; 103: 103795, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35500995

RESUMEN

Bone drilling tends to cause mechanical damages and thermal necrosis in the vicinity of the drilled hole, which can deteriorate the surgery quality and patients' recovery. Understanding the cutting forces generation mechanism is crucial in controlling thrust force and bone temperature for optimum tool design. In this study, a novel crescent drill bit featuring an improved positive rake angle distribution was designed to reduce the thrust force and temperature elevation. On this basis, a mechanistic model for predicting thrust force and torque was proposed for drill bits with different geometries (twist drill and crescent drill). The proposed model was established in the polar coordinate system to precisely calculate the curvilinear integral of the crescent cutting edges. Drilling experiments were carried out using two types of drill bit under different cutting conditions and results showed that our proposed model agrees well with the experimental data. The experimental results also demonstrated that our tool design can significantly reduce the thrust force and reduce the bone temperature below the thermal threshold without coolant, providing a clinical option for coolant free drilling.


Asunto(s)
Procedimientos Ortopédicos , Procedimientos de Cirugía Plástica , Huesos/cirugía , Humanos , Procedimientos Ortopédicos/métodos , Temperatura , Torque
20.
Mol Ther Nucleic Acids ; 26: 295-306, 2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34513311

RESUMEN

Accumulating evidence shows that tRNA-derived fragments are a novel class of functional small non-coding RNA; however, their roles in aortic dissection (AD) are still unknown. In this study, we found that 5'-tiRNA-Cys-GCA was significantly downregulated in human and mouse models of aortic dissection. The abnormal proliferation, migration, and phenotypic transition of vascular smooth muscle cells (VSMCs) played a crucial role in the initiation and progression of aortic dissection, with 5'-tiRNA-Cys-GCA as a potential phenotypic switching regulator, because its overexpression inhibited the proliferation and migration of VSMCs and increased the expression of contractile markers. In addition, we verified that signal transducer and activator of transcription 4 (STAT4) was a direct downstream target of 5'-tiRNA-Cys-GCA. We found that the STAT4 upregulation in oxidized low-density lipoprotein (ox-LDL)-treated VSMCs, which promoted cell proliferation, migration, and phenotypic transformation, was reversed by 5'-tiRNA-Cys-GCA. Furthermore, 5'-tiRNA-Cys-GCA treatment reduced the incidence and prevented the malignant process of angiotensin II- and ß-aminopropionitrile-induced AD in mice. In conclusion, our findings reveal that 5'-tiRNA-Cys-GCA is a potential regulator of the AD pathological process via the STAT4 signaling pathway, providing a novel clinical target for the development of future treatment strategies for aortic dissection.

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