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1.
Materials (Basel) ; 17(3)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38591564

RESUMEN

In sodium-cooled fast reactors, the wettability of sodium with materials is closely related to sodium-related operations and the detection accuracy of instruments and meters, so how to achieve the selection of materials with different wettability requirements is a key problem in engineering design. To meet these requirements, the wetting behaviors of liquid sodium with nine transition metals were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), and molecular dynamics (MD) simulations. The results show that metals such as zinc and gold, which react with sodium to form intermetallic compounds at the interface, exhibit superior wettability. Followed by the metals that have strong interatomic interactions even though they do not react with sodium or dissolve each other, such as cobalt, nickel and copper, while the wettability of these systems tends to be poor at low temperatures. Systems that do not react with each other or have strong interatomic affinities proved to be the most difficult to wet. Notably, metals with the closest-packed crystal structures of fcc and hcp generally have better wettability than those with a bcc structure. They can be a valuable guide for experimental research and technical control.

2.
Dis Colon Rectum ; 67(6): 834-840, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38426539

RESUMEN

BACKGROUND: Postoperative bowel dysfunction, also known as low anterior resection syndrome, is common in rectal cancer survivors and significantly impacts quality of life. Although long-term longitudinal follow-up is lacking, improvement of the syndrome is commonly believed to happen only within the first 2 years. OBJECTIVE: This study aimed to depict the longitudinal evolvement of low anterior resection syndrome beyond 3 years and explore factors associated with changes. DESIGN: Longitudinal long-term follow-ups were performed for the single center with the largest cohort within the multicenter FOWARC randomized controlled trial. SETTING: A quaternary referral center. PATIENTS: Individuals diagnosed with rectal cancer who received long-course neoadjuvant chemotherapy or chemoradiotherapy, followed by sphincter-preserving radical proctectomy. MAIN OUTCOME MEASUREMENTS: Change of low anterior resection syndrome score and stoma status. RESULTS: Of the 220 patients responding to the first follow-up at a median of 39 months, 178 (80.9%) responded to the second follow-up after a median of 83 months. During this interval, the mean low anterior resection syndrome score improved from 29.5 (95% CI, 28.3-30.7) to 18.6 (95% CI, 16.6-20.6). Fifty-six (31.5%) patients reported improvement from major to no/minor severity, and 6 (3.4%) patients had new stomas because of severe bowel dysfunction. Neoadjuvant radiotherapy ( p = 0.016) was independently and negatively associated with improvement of the score. LIMITATIONS: Loss of follow-up during the long-term follow-ups. CONCLUSIONS: Most rectal cancer survivors with low anterior resection syndrome continued to improve beyond 3 years after proctectomy. Neoadjuvant radiotherapy was negatively associated with long-term improvement of low anterior resection syndrome. See Video Abstract . CAMBIO A LARGO PLAZO DEL SNDROME DE RESECCIN ANTERIOR BAJA EN SUPERVIVIENTES DE CNCER DE RECTO SEGUIMIENTO LONGITUDINAL DE UN ENSAYO CONTROLADO ALEATORIO: ANTECEDENTES:La disfunción intestinal posoperatoria, también conocida como síndrome de resección anterior baja, es común en los sobrevivientes de cáncer de recto y afecta significativamente la calidad de vida. Aunque falta un seguimiento longitudinal a largo plazo, comúnmente se cree que la mejoría del síndrome ocurre sólo dentro de los primeros dos años.OBJETIVO:Este estudio tiene como objetivo representar la evolución longitudinal del síndrome de resección anterior baja más allá de los 3 años y explora los factores asociados con el cambio.DISEÑO:Se realizaron seguimientos longitudinales a largo plazo para el único centro con la cohorte más grande dentro del ensayo controlado aleatorio multicéntrico FOWARC.AJUSTE:Un centro de referencia cuaternario.PACIENTES:Individuos diagnosticados con cáncer de recto que recibieron quimioterapia neoadyuvante de larga duración o quimiorradioterapia, seguida de proctectomía radical con preservación del esfínter.PRINCIPALES MEDICIONES DE RESULTADO:Cambio en la puntuación del síndrome de resección anterior baja y el estado del estoma.RESULTADOS:De los 220 pacientes que respondieron al primer seguimiento con una mediana de 39 meses, 178 (80,9%) respondieron al segundo seguimiento después de una mediana de 83 meses. Durante el intervalo, la puntuación media del síndrome de resección anterior baja mejoró de 29,5 (intervalo de confianza [IC] del 95%: 28,3-30,7) a 18,6 (IC del 95%: 16,6-20,6). 56 (31,5%) pacientes informaron una mejoría de mayor a ninguna gravedad, y 6 (3,4%) pacientes tuvieron un nuevo estoma debido a una disfunción intestinal grave. La radiación neoadyuvante (p = 0,016) se asoció de forma independiente y negativa con la mejora de la puntuación.LIMITACIONES:Pérdida de seguimiento durante los seguimientos a largo plazo.CONCLUSIÓN:La mayoría de los sobrevivientes de cáncer de recto con síndrome de resección anterior baja continuaron mejorando más allá de los 3 años después de la proctectomía. La radiación neoadyuvante se asoció negativamente con la mejora a largo plazo del síndrome de resección anterior baja. (Traducción-Dr Yolanda Colorado ).


Asunto(s)
Supervivientes de Cáncer , Terapia Neoadyuvante , Complicaciones Posoperatorias , Proctectomía , Neoplasias del Recto , Humanos , Neoplasias del Recto/cirugía , Neoplasias del Recto/terapia , Masculino , Femenino , Proctectomía/métodos , Proctectomía/efectos adversos , Persona de Mediana Edad , Anciano , Síndrome , Supervivientes de Cáncer/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios de Seguimiento , Estudios Longitudinales , Terapia Neoadyuvante/métodos , Calidad de Vida , Incontinencia Fecal/etiología , Incontinencia Fecal/epidemiología , Adulto , Síndrome de Resección Anterior Baja
3.
Bioresour Technol ; 396: 130433, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38342281

RESUMEN

Cassava (Manihot esculenta Crantz) leaves, the primary by-product of cassava processing, constitute a significant protein source, accounting for 18 to 38 percent on a dry weight basis. Despite their nutritional value, a substantial portion of these leaves is often discarded post-harvest, resulting in notable resource waste. This study employs metagenomic technology to investigate the protein degradation mechanism in cassava leaves, aiming to provide a technical reference for value-added of this by-product. Following a 36-hour period of natural fermentation, the protein degradation rate reached 58%, a phenomenon intricately linked to both the microbial community structure and its functional properties. Notably, Lactococcus and Enterobacter, recognized for their abundant protease activity, were predominant. Metagenomically assembled genomes further revealed Lactococcus's substantial role in producing flavors and active compounds, including amino acids and peptides. This study offers novel perspectives to the foodization and high-value utilization of cassava by-products, emphasizing the sustainable exploitation of biomass resources.


Asunto(s)
Manihot , Fermentación , Manihot/química , Manihot/metabolismo , Proteolisis , Hojas de la Planta/química
4.
J Affect Disord ; 350: 755-760, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38211752

RESUMEN

BACKGROUND: Non-suicidal self-injury (NSSI) could lead to serious problems (exp. suicidal attempts) among children and adolescents. Positive youth development (PYD) focuses on comprehensive development instead of a single problem. This study aims to explore the longitudinal relationship between NSSI and PYD among Chinese children and adolescents. METHODS: The longitudinal study used the three-wave dataset from the Chengdu Positive Child Development (CPCD) in southwest China between 2019 and 2021, including 10,370 participants. The parallel process Latent Growth Curve Model (LGCM) was utilized to analyze the relationship between PYD and NSSI across time. RESULTS: The study results demonstrated that the initial level of NSSI is negatively associated with the initial value (ß = -0.730, p < 0.01) and the growth rate (ß = -0.012, p < 0.01) of PYD, and the development rate of the two variables are negatively related to each other(ß = -0.120, p < 0.01). LIMITATIONS: The specific relationships between PYD attributes and NSSI should be explored in the future. And the cultural variation among countries deserves more research. Moreover, the dynamic cohort research leads to a relatively high loss of participants. CONCLUSIONS: PYD and NSSI are closely associated among children and adolescents. Instead of playing a protective role, PYD tends to be predicted by NSSI behaviors over time.


Asunto(s)
Conducta Autodestructiva , Adolescente , Niño , Humanos , China/epidemiología , Estudios Longitudinales , Factores de Riesgo , Conducta Autodestructiva/epidemiología , Pueblos del Este de Asia
5.
Heart Fail Rev ; 29(2): 395-404, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37865929

RESUMEN

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disorder characterized by left ventricular hypertrophy. Sudden cardiac death (SCD) is a rare but the most catastrophic complication in patients with HCM. Implantable cardioverter-defibrillators (ICDs) are widely recognized as effective preventive measures for SCD. Individualized risk stratification and early intervention in HCM can significantly improve patient prognosis. In this study, we review the latest findings regarding pathogenesis, risk stratification, and prevention of SCD in HCM patients, highlighting the clinic practice of cardiovascular magnetic resonance imaging for SCD management.


Asunto(s)
Cardiomiopatía Hipertrófica , Desfibriladores Implantables , Humanos , Factores de Riesgo , Cardiomiopatía Hipertrófica/complicaciones , Cardiomiopatía Hipertrófica/terapia , Muerte Súbita Cardíaca/etiología , Muerte Súbita Cardíaca/prevención & control , Corazón , Desfibriladores Implantables/efectos adversos , Medición de Riesgo
6.
Psychol Res Behav Manag ; 16: 4491-4500, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37936973

RESUMEN

Background: Nonsuicidal self-injury (NSSI) is an overwhelming social problem in children and adolescents. Focusing on the change of NSSI behavior, including onset, cessation, and maintenance, is crucial to developing effective prevention and intervention strategies. This study explored the effect of mental health status (depressive and anxiety symptoms) and family function on NSSI. Methods: The study sample comprised 7554 children and adolescents based on the first two rounds of the Chengdu Positive Child Development (CPCD) dataset in China. Depressive and anxiety symptoms measured mental health status. The self-reported questionnaires also assessed NSSI behaviors and family function. The interrelationship between NSSI behaviors, mental health status, and family function was evaluated. Logistic regression and linear regression were performed to examine the interrelationship between mental health status, family function and NSSI behaviors. Sensitivity analysis was performed. Results: In this study, 2167 (28.69%) participants reported NSSI at baseline and 2101 (27.81%) at follow-up. Depression, anxiety, and family function were salient influential factors in the prevalence, onset, and cessation of NSSI. Parents' accompaniment showed a significant effect on the prevalence of NSSI. Conclusion: Depression, anxiety, family function, and parents' accompaniment are all associated with NSSI behaviors. Strategies targeting mental health status and family function could effectively protect children and adolescents from NSSI behaviors.

7.
EClinicalMedicine ; 63: 102172, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37662524

RESUMEN

Background: Previous studies have reported that tafamidis treatment was associated with better outcomes in patients with transthyretin amyloid cardiomyopathy (ATTR-CM) compared with those without tafamidis treatment. Therefore, we aimed to systematically assess the association of tafamidis treatment with outcomes in patients with ATTR-CM. Methods: The protocol for this systematic review and meta-analysis was registered in the PROSPERO (CRD42022381985). Pubmed, Ovid Embase, Scopus, Cochrane Library, and Web of Science were interrogated to identify studies that evaluated the impact of tafamidis on prognosis in ATTR-CM, from January 1, 2000 to June 1, 2023. A random-effects model was used to determine the pooled risk ratio (RR) for the adverse endpoints. In addition, the main outcomes included all-cause death or heart transplantation, the composite endpoints included all-cause death, heart transplantation, cardiac-assist device implantation, heart failure exacerbations, and hospitalization. Findings: Fifteen studies comprising 2765 patients (mean age 75.9 ± 9.3 years; 83.7% male) with a mean follow-up duration of 18.7 ± 17.1 months were included in the meta-analysis. There was a decrease in left ventricular ejection fraction (LVEF) (standard mean differences (SMD: -0.17; 95% confidence interval (CI), -0.31 to -0.03; P = 0.02) but were no significant differences in intraventricular septum (IVS) thickness or global longitudinal strain (GLS) after tafamidis treatment. However, subgroup analysis showed no significant deterioration in LVEF in the patients with wild-type ATTR after tafamidis treatment (SMD: -0.11; 95% CI, -0.34 to 0.12, P = 0.34). In addition, the group with tafamidis treatment had a decreased risk for all-cause death or heart transplantation compared to patients without treatment (the pooled RR, 0.44; 95% CI, 0.31-0.65; P < 0.01). Subgroup analysis showed that there was no significant difference of tafamidis on the outcomes in patients with wild-type or hereditary ATTR (RR, 0.44; 95% CI, 0.27-0.73 versus 0.21, 95% CI, 0.11-0.40, P = 0.08). Furthermore, tafamidis treatment was associated with a lower risk of the composite endpoint (RR, 0.57; 95% CI, 0.42-0.77; P < 0.01). Interpretation: Our findings suggested that there was no significant deterioration in LVEF in the patients with wild-type ATTR after tafamidis treatment. In addition, tafamidis treatment was associated with a low risk of all-cause death and adverse cardiovascular events. Funding: This work was supported by grants from the Natural Science Foundation of Sichuan Province [Grant Number: 23NSFSC4589] and the National Natural Science Foundation of China [Grant Number: 82202248].

8.
Int J Mol Sci ; 24(15)2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37569514

RESUMEN

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS), triggered by various pathogenic factors inside and outside the lungs, leads to diffuse lung injury and can result in respiratory failure and death, which are typical clinical critical emergencies. Severe acute pancreatitis (SAP), which has a poor clinical prognosis, is one of the most common diseases that induces ARDS. When SAP causes the body to produce a storm of inflammatory factors and even causes sepsis, clinicians will face a two-way choice between anti-inflammatory and anti-infection objectives while considering the damaged intestinal barrier and respiratory failure, which undoubtedly increases the difficulty of the diagnosis and treatment of SAP-ALI/ARDS. For a long time, many studies have been devoted to applying glucocorticoids (GCs) to control the inflammatory response and prevent and treat sepsis and ALI/ARDS. However, the specific mechanism is not precise, the clinical efficacy is uneven, and the corresponding side effects are endless. This review discusses the mechanism of action, current clinical application status, effectiveness assessment, and side effects of GCs in the treatment of ALI/ARDS (especially the subtype caused by SAP).


Asunto(s)
Lesión Pulmonar Aguda , Pancreatitis , Síndrome de Dificultad Respiratoria , Insuficiencia Respiratoria , Sepsis , Humanos , Glucocorticoides/uso terapéutico , Enfermedad Aguda , Pancreatitis/complicaciones , Síndrome de Dificultad Respiratoria/patología , Lesión Pulmonar Aguda/etiología , Lesión Pulmonar Aguda/complicaciones , Sepsis/complicaciones
9.
Curr Probl Cardiol ; 48(11): 101875, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37331610

RESUMEN

Accurate identification of hypertrophic cardiomyopathy (HCM) patients at high risk of sudden cardiac death (SCD) event is challenging. The objective of this study was to validate the three SCD risk stratifications recommended by the 2014 European Society of Cardiology (ESC) guideline, the 2020 American Heart Association /American College of Cardiology (AHA/ACC) guideline, and the 2022 ESC guideline in Chinese patients with HCM. Our study population are made up of a cohort of 856 HCM patients without prior SCD events. The endpoint was defined as SCD or equivalent events (successful resuscitation after cardiac arrest or appropriate ICD shock for ventricular tachycardia or ventricular fibrillation). During a median follow-up of 43 months, SCD endpoints occurred in 44 (5.1%) patients. A total of 34 (77.3%) patients suffering from SCD events were classified correctly into high-risk groups by the 2020 AHA/ACC guideline, 27(61.4%) by the 2022 ESC guideline, and 13 (29.6%) by the 2014 ESC guideline. The C-statistic of the 2020 AHA/ACC guideline was 0.68 (95% CI, 0.60-0.76), which performed better than the 2022 ESC guideline (0.65: 95% CI, 0.56-0.73), and the 2014 ESC guideline (0.58: 95% CI, 0.48-0.67). The 2020 AHA/ACC guideline displayed better discrimination for SCD risk stratification in Chinese HCM patients than the other two guidelines, with a higher sensitivity but lower specificity.


Asunto(s)
Cardiomiopatía Hipertrófica , Muerte Súbita Cardíaca , Humanos , Estados Unidos , Medición de Riesgo , Factores de Riesgo , Muerte Súbita Cardíaca/epidemiología , Muerte Súbita Cardíaca/etiología , Muerte Súbita Cardíaca/prevención & control , Arritmias Cardíacas , Cardiomiopatía Hipertrófica/complicaciones , Cardiomiopatía Hipertrófica/diagnóstico , Cardiomiopatía Hipertrófica/terapia , China/epidemiología
10.
Materials (Basel) ; 16(8)2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37109783

RESUMEN

Concrete structure performance continuously deteriorates during operation, and the performance is simultaneously affected by chloride corrosion and repeated traffic loading. Repeated-loading-induced cracks have an impact on the rate of chloride corrosion. Chloride-induced concrete corrosion also affect the stress level of the structure under loading. Therefore, the coupled effect of repeated loading and chloride corrosion on the structural performance needs to be investigated. An upgraded test device was developed for chloride corrosion testing of unsaturated concrete structures under repeated loading. Based on the experimental results, considering the influence of repeated loading on the moisture diffusion coefficient and the chloride diffusion coefficient, a chloride transport model for unsaturated concrete under the coupled effect of repeated uniaxial compressive loading and corrosion was established. The chloride concentration under coupled loading was determined by the Crank-Nicolson finite difference method and the Thomas algorithm, and then chloride transport under the coupled effect of repeated loading and corrosion was analyzed. The results showed that the stress level and the repeated loading cycles directly affect the relative volumetric water content and chloride concentration in unsaturated concrete. The effect of chloride corrosion is more severe in unsaturated concrete compared to saturated concrete.

11.
Chem Commun (Camb) ; 59(33): 4978-4981, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37017210

RESUMEN

Rh-catalyzed selective C-H functionalization of indoles with two routes was developed: an alkenylation-annulation with the addition of KHSO4 and alkenylation-elimination in the presence of CsOAc to the corresponding products, respectively. Notably, one-pot hydrolysis and benzoylation of the annulation products successfully afforded easily separable ß-(1H-indol-2-yl)-ß-amino acid derivatives.

12.
Org Lett ; 25(11): 1850-1855, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-36896992

RESUMEN

Pd(II)-catalyzed oxidation of terminal olefins to methyl ketones has emerged as an attractive strategy for organic synthesis. Here we report the Pd(II)-catalyzed selective oxidation of olefins using tert-butyl hydroperoxide as the oxidant and 2-(1H-indazol-1-yl)quinoline as the ligand. A wide range of olefins were well tolerated in this reaction system to provide methyl ketones, whereas the presence of Ac2O initiated the oxo-acyloxylation to afford the α-acetoxyacetone products. Isotope labeling studies and active-intermediate-capture experiments were performed to elucidate the underlying selective reaction mechanism. Notably, the generation of α-acetoxyacetone products involves the palladium enolate intermediate while the methyl ketone products were generated through the most commonly proposed alkylperoxide intermediates, followed by 1,2-hydride migration.

13.
JACC Cardiovasc Imaging ; 16(3): 361-372, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36752447

RESUMEN

BACKGROUND: Left ventricular abnormalities in cardiac sarcoidosis (CS) are associated with adverse cardiovascular events, whereas the prognostic value of right ventricular (RV) involvement found on cardiac magnetic resonance is unclear. OBJECTIVES: This study aimed to systematically assess the prognostic value of right ventricular ejection fraction (RVEF) and RV late gadolinium enhancement (LGE) in known or suspected CS. METHODS: This study was prospectively registered in PROSPERO (CRD42022302579). PubMed, Embase, and Web of Science were searched to identify studies that evaluated the association between RVEF or RV LGE on clinical outcomes in CS. A composite endpoint of all-cause death, cardiovascular events, or sudden cardiac death (SCD) was used. A meta-analysis was performed to determine the pooled risk ratio (RR) for these adverse events. The calculated sensitivity, specificity, and area under the curve with 95% CIs were weighted and summarized. RESULTS: Eight studies including a total of 899 patients with a mean follow-up duration of 3.2 ± 0.7 years were included. The pooled RR of RV systolic dysfunction was 3.1 (95% CI: 1.7-5.5; P < 0.01) for composite events and 3.0 (95% CI: 1.3-7.0; P < 0.01) for SCD events. In addition, CS patients with RV LGE had a significant risk for composite events (RR: 4.8 [95% CI: 2.4-9.6]; P < 0.01) and a higher risk for SCD (RR: 9.5 [95% CI: 4.4-20.5]; P < 0.01) than patients without RV LGE. Furthermore, the pooled area under the curve, sensitivity, and specificity of RV LGE for identifying patients with CS who were at highest SCD risk were 0.8 (95% CI: 0.8-0.9), 69% (95% CI: 50%-84%), and 90% (95% CI: 70%-97%), respectively. CONCLUSIONS: In patients with known or suspected CS, RVEF and RV LGE were both associated with adverse events. Furthermore, RV LGE shows good discrimination in identifying CS patients at high risk of SCD.


Asunto(s)
Cardiomiopatías , Cardiopatías Congénitas , Miocarditis , Sarcoidosis , Humanos , Miocardio , Pronóstico , Medios de Contraste , Volumen Sistólico , Factores de Riesgo , Valor Predictivo de las Pruebas , Función Ventricular Derecha , Gadolinio , Sarcoidosis/complicaciones , Sarcoidosis/diagnóstico por imagen , Muerte Súbita Cardíaca/etiología , Miocarditis/complicaciones
14.
BJS Open ; 6(6)2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-36321379

RESUMEN

BACKGROUND: Neoadjuvant radiation has been increasingly associated with postoperative bowel dysfunction, including low anterior resection syndrome (LARS). Although permanent stoma often results from severe bowel dysfunction and significantly impacts quality of life, the presence of stoma paradoxically excludes patients from functional follow-up. Hence, stoma status is rarely reported along with LARS, while assessment of both is essential for the comprehensive evaluation of bowel dysfunction in long-term survivors of rectal cancer. METHOD: Patients enrolled into the Neoadjuvant FOLFOX6 Chemotherapy with or without Radiation in Rectal Cancer (FOWARC) multicentre randomized clinical trial were randomized to receive long-course neoadjuvant chemoradiotherapy (nCRT) or chemotherapy (nCT) followed by sphincter-saving proctectomy and longitudinal follow-up. The primary outcome of the trial was disease-free survival. LARS score and stoma status were assessed secondarily for postoperative bowel function in the largest single-centre cohort of the trial. RESULTS: Overall, 327 patients with locally advanced rectal cancer were enrolled in the original trial and 203 responded after a median follow-up of 83.4 months, of whom 24 (11.8 per cent) had persistent stoma, and 48 patients (23.6 per cent) reported major LARS. Compared with the nCT group, the nCRT group reported more persistent stomas (16.5 per cent versus 4.9 per cent, P = 0.014), and more major LARS in patients without persistent stoma (34.7 per cent versus 16.7 per cent, P = 0.003). The combined prevalence of persistent stoma and major LARS was significantly higher in the nCRT group (45.5 per cent versus 20.7 per cent, P < 0.001). Long-course neoadjuvant radiation (OR 2.20, 95 per cent c.i. 1.10 to 4.40, P = 0.027), height of anastomosis (OR 0.74, 95 per cent c.i. 0.61 to 0.91, P = 0.004), and anastomotic leak (OR 4.97, 95 per cent c.i. 2.24 to 11.05, P < 0.001) were associated with persistent stoma and major LARS in multivariate analysis. CONCLUSION: More than one-third of patients receiving sphincter-saving proctectomy reported major LARS or persistent stoma at long-term follow-up. Long-course neoadjuvant radiation, low anastomosis, and postoperative leak are independent risk factors for persistent stoma and major LARS.


Asunto(s)
Neoplasias del Recto , Humanos , Neoplasias del Recto/cirugía , Terapia Neoadyuvante/efectos adversos , Complicaciones Posoperatorias/epidemiología , Calidad de Vida , Estudios de Seguimiento , Síndrome , Recto/cirugía
15.
RSC Adv ; 12(19): 11722-11731, 2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35432946

RESUMEN

We present results of an unbiased structure search for the lowest energy crystalline structures of various stoichiometric iridium borides, using first-principles calculations combined with particle swarm optimization algorithms. As a result, besides three stable phases of C2/m-Ir3B2, Fmm2-Ir4B3, and Cm-Ir4B5, three promising metastable phases, namely, P21/m-Ir2B, P21/m-IrB, and Pnma-Ir3B4, whose energies are within 20 meV per atom above the convex hull curve, are also identified at ambient pressure. The high bulk modulus of 301 GPa, highest shear modulus of 148 GPa, and smallest Poisson's ratio of 0.29 for C2/m-Ir3B2 make it a promising low compressible material. C2/m-Ir3B2 is predicted to possess the highest Vickers hardnesses, with a Vickers hardness of 13.1 GPa and 19.4 GPa based on Chen's model and Mazhnik-Oganov's model respectively, and a high fracture toughness of 5.17 MPa m0.5. The anisotropic indexes and the three-dimensional surface constructions of Young's modulus indicate that Ir-B compounds are anisotropic with the sequence of the elastic anisotropy of Ir2B > IrB > Ir4B5 > Ir3B4 > Ir4B3 > Ir3B2. Remarkably, these iridium borides are all ductile. We further find that the four Ir-B phases of P21/m-Ir2B, C2/m-Ir3B2, P21/m-IrB, and Fmm2-Ir4B3 possess dominant Ir-B covalent bonding character, while strong B-B and Ir-B covalent bonds are present in Cm-Ir4B5 and Pnma-Ir3B4, which are responsible for their excellent mechanical properties.

16.
Chem Sci ; 13(5): 1298-1306, 2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35222913

RESUMEN

Pd-catalyzed C(sp3)-H oxygenation has emerged as an attractive strategy for organic synthesis. The most commonly proposed mechanism involves C(sp3)-H activation followed by oxidative addition of an oxygen electrophile to give an alkylpalladium(iv) species and further C(sp3)-O reductive elimination. In the present study of γ-C(sp3)-H acyloxylation of amine derivatives, we show a different mechanism when tert-butyl hydroperoxide (TBHP) is used as an oxidant-namely, a bimetallic oxidative addition-oxo-insertion process. This catalytic model results in an alkoxypalladium(ii) intermediate from which acyloxylation and alkoxylation products are formed. Experimental and computational studies, including isolation of the putative post-oxo-insertion alkoxypalladium(ii) intermediates, support this mechanistic model. Density functional theory reveals that the classical alkylpalladium(iv) oxidative addition pathway is higher in energy than the bimetallic oxo-insertion pathway. Further kinetic studies revealed second-order dependence on [Pd] and first-order on [TBHP], which is consistent with DFT analysis. This procedure is compatible with a wide range of acids and alcohols for γ-C(sp3)-H oxygenation. Preliminary functional group transformations of the products underscore the great potential of this protocol for structural manipulation.

17.
J Surg Oncol ; 125(3): 448-456, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34689328

RESUMEN

AIM: Bowel dysfunction after sphincter-preserving proctectomy, also known as low anterior resection syndrome (LARS), has significant impact on survivors of rectal cancer. This study aimed to assess the temporal change of LARS beyond 2 years after proctectomy, which has not been fully studied. METHODS: We longitudinally enrolled consecutive patients who had received total mesorectal excision in a tertiary academic medical center, with preoperative neoadjuvant therapy if indicated. LARS score was longitudinally assessed by two serial follow-ups, with a fixed interval of 18 months. RESULTS: Overall, 107 patients responded for the first follow-up after a median of q20 months, 96 of whom responded for the second follow-up after a median of 38 months. At the first follow-up, 48 patients (44.9%) reported major LARS, compared with 23 (24.0%) at the second follow-up (p < 0.001). Mean LARS score improved from 27.3 to 18.6, mostly from "urgency" (12.2 vs. 6.2, p < 0.001) and "clustering of stools" (9.7 vs. 7.7, p = 0.001). Anastomosis less than 3 cm from the anal verge was independently associated with LARS improvement. CONCLUSION: Bowel dysfunction continues to improve 2 years after total mesorectal excision, with most symptom relief in urgency and stool clustering, especially in patients with lower anastomosis.


Asunto(s)
Adenocarcinoma/cirugía , Incontinencia Fecal/epidemiología , Complicaciones Posoperatorias/epidemiología , Proctectomía/efectos adversos , Neoplasias del Recto/cirugía , Adenocarcinoma/patología , Incontinencia Fecal/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Neoplasias del Recto/patología , Síndrome , Factores de Tiempo
18.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 33(10): 1266-1271, 2021 Oct.
Artículo en Chino | MEDLINE | ID: mdl-34955142

RESUMEN

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a life-threatening lung disease characterized by refractory hypoxemia. Metabolomics is an emerging discipline for qualitative and quantitative analysis of small molecular weight metabolites in organisms or cells. Mass attention has been paid to its role in disease diagnosis and treatment. Recently, many metabolites based on metabolomics have been proposed as potential biomarkers for early development and prognosis of ALI/ARDS, and provide insights into new targeted interventions. Based on metabolomics, this article discusses the role of endogenous metabolites in the pathogenesis and biomarkers of ALI/ARDS, and summarizes its application in medical therapy.


Asunto(s)
Lesión Pulmonar Aguda , Síndrome de Dificultad Respiratoria , Biomarcadores , Humanos , Metabolómica , Pronóstico
19.
Front Cardiovasc Med ; 8: 766287, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34957254

RESUMEN

Objectives: To identify significant radiomics features derived from late gadolinium enhancement (LGE) images in participants with hypertrophic cardiomyopathy (HCM) and assess their prognostic value in predicting sudden cardiac death (SCD) endpoint. Method: The 157 radiomic features of 379 sequential participants with HCM who underwent cardiovascular magnetic resonance imaging (MRI) were extracted. CoxNet (Least Absolute Shrinkage and Selection Operator (LASSO) and Elastic Net) and Random Forest models were applied to optimize feature selection for the SCD risk prediction and cross-validation was performed. Results: During a median follow-up of 29 months (interquartile range, 20-42 months), 27 participants with HCM experienced SCD events. Cox analysis revealed that two selected features, local binary patterns (LBP) (19) (hazard ratio (HR), 1.028, 95% CI: 1.032-1.134; P = 0.001) and Moment (1) (HR, 1.212, 95%CI: 1.032-1.423; P = 0.02) provided significant prognostic value to predict the SCD endpoints after adjustment for the clinical risk predictors and late gadolinium enhancement. Furthermore, the univariately significant risk predictor was improved by the addition of the selected radiomics features, LBP (19) and Moment (1), to predict SCD events (P < 0.05). Conclusion: The radiomics features of LBP (19) and Moment (1) extracted from LGE images, reflecting scar heterogeneity, have independent prognostic value in identifying high SCD risk patients with HCM.

20.
Sci Rep ; 11(1): 24319, 2021 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-34934092

RESUMEN

It is critical for the health monitoring of large-scale structures such as bridge, railway and tunnel to acquire the medium-frequency and high-frequency vibration signals. To solve the problems of low sensitivity and poor transverse anti-interference of the medium-frequency and high-frequency fiber acceleration sensor, a hinge-type Fiber Bragg Grating(FBG) acceleration sensor based on double elastic plate has been proposed, and the hinge and elastic plate are used as elastomer to realize the miniaturization and transverse interference suppression of the sensor. The MATLAB and the ANSYS are used for theoretical analysis and optimization of sensor sensitivity and resonance frequency, structural static stress analysis and modal simulation analysis, while the test system is built to test the sensor performance. The results show that the resonance frequency of the sensor is 1300 Hz; the sensor has a flat sensitivity response in the middle-high frequency band of 200-800 Hz; the sensitivity is about 20 pm/g, and the fiber central wavelength drift and acceleration have good linearity and stability, while the transverse anti-interference is about 3.16%, which provides a new idea for monitoring of medium-frequency and high-frequency vibration signals in large-scale structures.

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