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1.
J Dig Dis ; 25(3): 176-190, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38697922

RESUMEN

OBJECTIVES: Functional constipation (FC), a common functional gastrointestinal disorder, is usually overlapping with upper gastrointestinal symptoms (UGS). We aimed to explore the clinical characteristics of patients with FC overlapping UGS along with the related risk factors. METHODS: The differences in the severity of constipation symptoms, psychological state, quality of life (QoL), anorectal motility and perception function, autonomic function, and the effect of biofeedback therapy (BFT) among patients with FC in different groups were analyzed, along with the risk factors of overlapping UGS. RESULTS: Compared with patients with FC alone, those with FC overlapping UGS had higher scores in the Patient Assessment of Constipation Symptoms and Self-Rating Anxiety Scale and lower scores in the Short Form-36 health survey (P < 0.05). Patients with FC overlapping UGS also had lower rectal propulsion, more negative autonomic nervous function, and worse BFT efficacy (P < 0.05). Overlapping UGS, especially overlapping functional dyspepsia, considerably affected the severity of FC. Logistic regression model showed that age, body mass index (BMI), anxiety, exercise, and sleep quality were independent factors influencing overlapping UGS in patients with FC. CONCLUSIONS: Overlapping UGS reduces the physical and mental health and the QoL of patients with FC. It also increases the difficulty in the treatment of FC. Patient's age, BMI, anxiety, physical exercise, and sleep quality might be predictors for FC overlapping UGS.


Asunto(s)
Estreñimiento , Calidad de Vida , Humanos , Estreñimiento/fisiopatología , Estreñimiento/psicología , Estreñimiento/etiología , Femenino , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto , Índice de Severidad de la Enfermedad , Biorretroalimentación Psicológica , Ansiedad , Enfermedades Gastrointestinales/psicología , Enfermedades Gastrointestinales/fisiopatología , Enfermedades Gastrointestinales/etiología , Anciano , Motilidad Gastrointestinal/fisiología
3.
Artículo en Inglés | MEDLINE | ID: mdl-38631536

RESUMEN

PURPOSE: The standard treatment schedule for unresectable stage III non-small cell lung cancer (NSCLC) is chemotherapy with concurrent radiation therapy (60 Gy delivered in 30 fractions), although moderately hypofractionated radiation therapy (Hypo-RT) has also been considered as an alternative strategy. This study aimed to compare the efficacy and toxicity of moderately Hypo-RT with helical TomoTherapy versus conventionally fractionated radiation therapy (Con-RT) in patients with unresectable stage III NSCLC receiving concurrent chemotherapy. METHODS AND MATERIALS: In this randomized, multicenter, nonblinded phase 3 clinical trial, eligible patients were randomised at a 1:1 ratio to either the Hypo-RT group (60 Gy in 20 fractions) or Con-RT group (60 Gy in 30 fractions). All patients received 2 cycles of concurrent platinum-based chemotherapy plus 2 cycles of consolidation therapy. The primary endpoint was 3-year overall survival (OS) in the intention-to-treat population. The secondary endpoints were progression-free survival and treatment-related adverse events. RESULTS: A total of 146 patients were enrolled from July 27, 2018, to November 1, 2021. The median follow-up was 46 months. The 3-year OS rates in the Hypo-RT and Con-RT groups were 58.4% and 38.4%, respectively (P = .02). The median OS from randomisation was 41 months in the Hypo-RT group and 30 months in the Con-RT group (hazard ratio, 0.61; 95% confidence interval, 0.40-0.94; P = .02). There was no significant difference in the rates of grade ≥2 treatment-related adverse events between the 2 groups. CONCLUSIONS: Moderately Hypo-RT using helical TomoTherapy may improve OS in patients with unresectable stage III NSCLC, while maintaining toxicity rates.

4.
Pharmacol Res Perspect ; 12(2): e1186, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38511246

RESUMEN

We conducted pharmacokinetic research wherein salcaprozate sodium (SNAC) was utilized as a penetration enhancer by incorporating it into pancreatic kininogenase (PK) to improve the bioavailability of pancreatic kininogenase enteric-coated tablets. We conducted in vitro studies on PK using the Caco-2 cell model and quantified PK levels using the enzyme-linked immunosorbent assay (ELISA) method. We conducted methodological verification by blending SNAC and PK powders into enteric-coated capsules, and studied the pharmacokinetic characteristics. Based on the PK transport assay, the cumulative permeation rates of the test group that employed a SNAC to PK ratio of 32:1, 16:1, 8:1, 4:1, and 2:1 were 13.574%, 7.597%, 10.653%, 3.755%, and 2.523%, respectively. We conducted a uniformity test on the powder that contained a blend of SNAC and PK. The relative standard deviations (RSDs) for both the power containing SNAC and the power not containing SNAC were less than 10%. Based on the methodological verification, in vivo pharmacokinetic study of PK met the experimental requirements. As indicated by the results of in vivo pharmacokinetic research on rats, the test group (This group used SNAC) had a PK AUC0-12 h of 5679.747 ng/L*h and t1/2 of 4.569 h, while the control group (This group did not use SNAC) had a PK AUC0-12 h of 4639.665 ng/L*h and t1/2 of 3.13 h. This study has established a low-cost, environmentally friendly, and safe SNAC synthesis route with high process yield suitable for industrial production. SNAC demonstrates an absorption-enhancing effect on PK, and the optimal ratio of SNAC to PK is determined to be 32:1.


Asunto(s)
Caprilatos , Calicreínas , Humanos , Ratas , Animales , Administración Oral , Células CACO-2
5.
Nutrition ; 117: 112227, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38486479

RESUMEN

OBJECTIVE: Radiation for locally advanced esophageal squamous cell carcinoma often is accompanied by radiation esophagitis, which interferes with oral intake. We aimed to develop a nomogram model to identify initially inoperable patients with relative and absolute weight loss who need prophylactic nutritional supplementation. METHODS: A total of 365 initially inoperable patients with locally advanced esophageal squamous cell carcinoma receiving radiotherapy between January 2018 and December 2022 were included in the study, which was divided into discovery and validation cohorts. Receiver operating characteristic and Kaplan-Meier curve analyses were performed to compare the areas under the curve and survival benefits. RESULTS: A total of 42.2% (154 of 365) of the patients had been diagnosed with cancer cachexia. The malnourished group had a higher interruption rate of radiotherapy and number of complication diseases (P < 0.05). Meanwhile, patients with malnutrition had lower lymphocytes and prognostic nutritional index (P < 0.05). The combined index showed a higher area under the curve value (0.67; P < 0.001) than number of complication diseases (area under the curve = 0.52) and prognostic nutritional index (area under the curve = 0.49) for relative weight loss (≥ 5%). Similarly, the combined index had a higher area under the curve value (0.79; P < 0.001) than number of complication diseases (area under the curve = 0.56), treatment regimens (area under the curve = 0.56), subcutaneous fat thickness (area under the curve = 0.60), pretreatment body weight (area under the curve = 0.61), neutrophils (area under the curve = 0.56), and prognostic nutritional index (area under the curve = 0.50) for absolute weight loss (≥ 5 kg). Absolute and relative weight loss remained independent prognostic factors, with short overall survival rates compared with the normal group (P < 0.05). Patients with high nomogram scores supported by nutritional intervention had less weight loss, better nutrition scores, and increased plasma CD8+ T cells, and interferon gamma. CONCLUSIONS: We developed a nomogram model that was intended to estimate relative and absolute weight loss in initially inoperable patients with locally advanced esophageal squamous cell carcinoma during radiotherapy, which might help facilitate an objective decision on prophylactic nutritional supplementation.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/radioterapia , Nomogramas , Neoplasias Esofágicas/complicaciones , Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/tratamiento farmacológico , Pérdida de Peso
6.
J Transl Med ; 22(1): 228, 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38431575

RESUMEN

BACKGROUND: We aimed to investigate the effects of PinX1 on non-small cell lung cancer(NSCLC) radiosensitivity and radiotherapy-associated tumor immune microenvironment and its mechanisms. METHODS: The effect of PinX1 silencing on radiosensitivity in NSCLC was assessed by colony formation and CCK8 assay, immunofluorescence detection of γ- H2AX and micronucleus assay. Western blot was used to assess the effect of PinX1 silencing on DNA damage repair pathway and cGAS-STING pathway. The nude mouse and Lewis lung cancer mouse model were used to assess the combined efficacy of PinX1 silencing and radiotherapy in vivo. Changes in the tumor immune microenvironment were assessed by flow cytometry for different treatment modalities in the Lewis luuse model. The interaction protein RBM10 was screened by immunoprecipitation-mass spectrometry. RESULTS: Silencing PinX1 enhanced radiosensitivity and activation of the cGAS-STING pathway while attenuating the DNA damage repair pathway. Silencing PinX1 further increases radiotherapy-stimulated CD8+ T cell infiltration and activation, enhances tumor control and improves survival in vivo; Moreover, PinX1 downregulation improves the anti-tumor efficacy of radioimmunotherapy, increases radioimmune-stimulated CD8+ T cell infiltration, and reprograms M2-type macrophages into M1-type macrophages in tumor tissues. The interaction of PinX1 and RBM10 may promote telomere maintenance by assisting telomerase localization to telomeres, thereby inhibiting the immunostimulatory effects of IR. CONCLUSIONS: In NSCLC, silencing PinX1 significantly contributed to the radiosensitivity and promoted the efficacy of radioimmunotherapy. Mechanistically, PinX1 may regulate the transport of telomerase to telomeres through interacting with RBM10, which promotes telomere maintenance and DNA stabilization. Our findings reveal that PinX1 is a potential target to enhance the efficacy of radioimmunotherapy in NSCLC patients.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Telomerasa , Animales , Ratones , Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Proteínas Supresoras de Tumor/genética , Proteínas de Ciclo Celular/metabolismo , Telomerasa/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , Línea Celular Tumoral , Tolerancia a Radiación , Microambiente Tumoral , Proteínas de Unión al ARN
7.
J Adv Res ; 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38402949

RESUMEN

INTRODUCTION: Abnormal alternative splicing (AS) contributes to aggressive intrahepatic invasion and metastatic spread, leading to the high lethality of hepatocellular carcinoma (HCC). OBJECTIVES: This study aims to investigate the functional implications of UPF3B-S (a truncated oncogenic splice variant) in HCC metastasis. METHODS: Basescope assay was performed to analyze the expression of UPF3B-S mRNA in tissues and cells. RNA immunoprecipitation, and in vitro and in vivo models were used to explore the role of UPF3B-S and the underlying mechanisms. RESULTS: We show that splicing factor HnRNPR binds to the pre-mRNA of UPF3B via its RRM2 domain to generate an exon 8 exclusion truncated splice variant UPF3B-S. High expression of UPF3B-S is correlated with tumor metastasis and unfavorable overall survival in patients with HCC. The knockdown of UPF3B-S markedly suppresses the invasive and migratory capacities of HCC cells in vitro and in vivo. Mechanistically, UPF3B-S protein targets the 3'-UTR of CDH1 mRNA to enhance the degradation of CDH1 mRNA, which results in the downregulation of E-cadherin and the activation of epithelial-mesenchymal transition. Overexpression of UPF3B-S enhances the dephosphorylation of LATS1 and the nuclear accumulation of YAP1 to trigger the Hippo signaling pathway. CONCLUSION: Our findings suggest that HnRNPR-induced UPF3B-S promotes HCC invasion and metastasis by exhausting CDH1 mRNA and modulating YAP1-Hippo signaling. UPF3B-S could potentially serve as a promising biomarker for the clinical management of invasive HCC.

8.
Plant Cell ; 36(4): 881-898, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37941457

RESUMEN

Double fertilization in many flowering plants (angiosperms) often occurs during the hot summer season, but the mechanisms that enable angiosperms to adapt specifically to high temperatures are largely unknown. The actin cytoskeleton is essential for pollen germination and the polarized growth of pollen tubes, yet how this process responds to high temperatures remains unclear. Here, we reveal that the high thermal stability of 11 Arabidopsis (Arabidopsis thaliana) actin-depolymerizing factors (ADFs) is significantly different: ADFs that specifically accumulate in tip-growing cells (pollen and root hairs) exhibit high thermal stability. Through ancestral protein reconstruction, we found that subclass II ADFs (expressed specifically in pollen) have undergone a dynamic wave-like evolution of the retention, loss, and regeneration of thermostable sites. Additionally, the sites of AtADF7 with high thermal stability are conserved in ADFs specific to angiosperm pollen. Moreover, the high thermal stability of ADFs is required to regulate actin dynamics and turnover at high temperatures to promote pollen germination. Collectively, these findings suggest strategies for the adaptation of sexual reproduction to high temperature in angiosperms at the cell biology level.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Factores Despolimerizantes de la Actina/metabolismo , Actinas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Temperatura , Germinación/genética , Arabidopsis/metabolismo , Polen/metabolismo , Tubo Polínico
9.
J Fish Dis ; 47(3): e13896, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38054569

RESUMEN

Nocardia seriolae is the primary aetiological agent of nocardiosis in fish, which causes mass mortality in freshwater and marine fish. ß-ketoacyl-ACP synthase (KAS) is one of the essential enzymes in the synthesis of mycolic acids (MASs) in Mycobacterium spp. and has been chosen as the target for therapeutic intervention in mycobacterial diseases. In the present study, a kasB homologue gene (kasB) was identified in the genome of N. seriolae, and the gene-deficient mutant (ΔkasB) was generated based on a clinical isolate, XSYC-Ns. Compared to the wild-type (WT) strain, the ΔkasB showed a measurably growth defect in vitro but retained the acid-fastness in acid-fast staining. Observation of the cell ultrastructure showed some alterations in the cell wall of the ΔkasB strain. Compared to its original strain, the cell wall lipid layer seemed sparser, and a wider electron-transparent zone was observed in the cell wall of ΔkasB strain. Moreover, the ΔkasB strain showed impaired ability of cell invasion as well as intracellular survival in the cell line originating from the head-kidney of the large yellow croaker (LYC-hK), compared to its original strain. In addition, the deficiency of ΔkasB significantly attenuated the virulence of N. seriolae in largemouth bass. The present study suggested that the ΔkasB gene might be involved in the synthesis of extracellular cell-wall lipids in N. seriolae and play a crucial role in its pathogenicity.


Asunto(s)
Lubina , Enfermedades de los Peces , Nocardiosis , Nocardia , Animales , Virulencia/genética , Enfermedades de los Peces/microbiología , Nocardia/genética , Nocardiosis/veterinaria , Nocardiosis/microbiología
10.
Plant Commun ; 5(3): 100787, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38158655

RESUMEN

A root hair is a polarly elongated single-celled structure that derives from a root epidermal cell and functions in uptake of water and nutrients from the surrounding environment. Previous reports have demonstrated that short periods of high pH inhibit root hair extension; but the effects of long-term high-pH treatment on root hair growth are still unclear. Here, we report that the duration of root hair elongation is significantly prolonged with increasing external pH, which counteracts the effect of decreasing root hair elongation rate and ultimately produces longer root hairs, whereas loss of actin-depolymerizing factor 8 and 11 (ADF8/11) function causes shortening of root hair length at high pH (pH 7.4). Accumulation of ADF8/11 at the tips of root hairs is inhibited by high pH, and increasing environmental pH affects the actin filament (F-actin) meshwork at the root hair tip. At high pH, the tip-focused F-actin meshwork is absent in root hairs of the adf8/11 mutant, actin filaments are disordered at the adf8/11 root hair tips, and actin turnover is attenuated. Secretory and recycling vesicles do not aggregate in the apical region of adf8/11 root hairs at high pH. Together, our results suggest that, under long-term exposure to high extracellular pH, ADF8/11 may establish and maintain the tip-focused F-actin meshwork to regulate polar trafficking of secretory/recycling vesicles at the root hair tips, thereby promoting root hair elongation.


Asunto(s)
Factores Despolimerizantes de la Actina , Actinas , Raíces de Plantas , Concentración de Iones de Hidrógeno
11.
Comput Mech ; 72(1): 173-194, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38107347

RESUMEN

The hierarchical deep-learning neural network (HiDeNN) (Zhang et al, Computational Mechanics, 67:207-230) provides a systematic approach to constructing numerical approximations that can be incorporated into a wide variety of Partial differential equations (PDE) and/or Ordinary differential equations (ODE) solvers. This paper presents a framework of the nonlinear finite element based on HiDeNN approximation (nonlinear HiDeNN-FEM). This is enabled by three basic building blocks employing structured deep neural networks: 1) A partial derivative operator block that performs the differentiation of the shape functions with respect to the element coordinates, 2) An r-adaptivity block that improves the local and global convergence properties and 3) A materials derivative block that evaluates the material derivatives of the shape function. While these building blocks can be applied to any element, specific implementations are presented in 1D and 2D to illustrate the application of the deep learning neural network. Two-step optimization schemes are further developed to allow for the capabilities of r-adaptivity and easy integration with any existing FE solver. Numerical examples of 2D and 3D demonstrate that the proposed nonlinear HiDeNN-FEM with r-adaptivity provides much higher accuracy than regular FEM. It also significantly reduces element distortion and suppresses the hourglass mode.

12.
Front Cell Infect Microbiol ; 13: 1298443, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38106470

RESUMEN

Background: Alterations in gut microbiota composition and function have been linked to the development and progression of thyroid cancer (TC). However, the exact nature of the causal relationship between them remains uncertain. Methods: A bidirectional two-sample Mendelian randomization (TSMR) analysis was conducted to assess the causal connection between gut microbiota (18,340 individuals) and TC (6,699 cases combined with 1,613,655 controls) using data from a genome-wide association study (GWAS). The primary analysis used the inverse-variance weighted (IVW) method to estimate the causal effect, with supplementary approaches including the weighted median, weighted mode, simple mode, and MR-Egger. Heterogeneity and pleiotropy were assessed using the Cochrane Q test, MR-Egger intercept test, and MR-PRESSO global test. A reverse TSMR analysis was performed to explore reverse causality. Results: This study identified seven microbial taxa with significant associations with TC. Specifically, the genus Butyrivibrio (OR: 1.127, 95% CI: 1.008-1.260, p = 0.036), Fusicatenibacter (OR: 1.313, 95% CI: 1.066-1.618, p = 0.011), Oscillospira (OR: 1.240, 95% CI: 1.001-1.536, p = 0.049), Ruminococcus2 (OR: 1.408, 95% CI: 1.158-1.711, p < 0.001), Terrisporobacter (OR: 1.241, 95% CI: 1.018-1.513, p = 0.032) were identified as risk factors for TC, while The genus Olsenella (OR: 0.882, 95% CI: 0.787-0.989, p = 0.031) and Ruminococcaceae UCG004 (OR: 0.719, 95% CI: 0.566-0.914, p = 0.007) were associated with reduced TC risk. The reverse MR analysis found no evidence of reverse causality and suggested that TC may lead to increased levels of the genus Holdemanella (ß: 0.053, 95% CI: 0.012~0.094, p = 0.011) and decreased levels of the order Bacillales (ß: -0.075, 95% CI: -0.143~-0.006, p = 0.033). No significant bias, heterogeneity, or pleiotropy was detected in this study. Conclusion: This study suggests a potential causal relationship between gut microbiota and TC, providing new insights into the role of gut microbiota in TC. Further research is needed to explore the underlying biological mechanisms.


Asunto(s)
Disbiosis , Neoplasias de la Tiroides , Humanos , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Causalidad , Neoplasias de la Tiroides/genética , Clostridiales
13.
Cell Rep ; 42(11): 113353, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-38007687

RESUMEN

Pollen tube integrity is required for achieving double fertilization in angiosperms. The rapid alkalinization factor4/19-ANXUR1/2-Buddha's paper seal 1/2 (RALF4/19-ANX1/2-BUPS1/2)-complex-mediated signaling pathway is critical to maintain pollen tube integrity, but the underlying mechanisms regulating the polar localization and distribution of these complex members at the pollen tube tip remain unclear. Here, we find that COBRA-like protein 11 (COBL11) loss-of-function mutants display a low pollen germination ratio, premature pollen tube burst, and seed abortion in Arabidopsis. COBL11 could interact with RALF4/19, ANX1/2, and BUPS1/2, and COBL11 functional deficiency could result in the disrupted distribution of RALF4 and ANX1, altered cell wall composition, and decreased levels of reactive oxygen species in pollen tubes. In conclusion, COBL11 is a regulator of pollen tube integrity during polar growth, which is conducted by a direct interaction that ensures the correct localization and polar distribution of RALF4 and ANX1 at the pollen tube tip.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Tubo Polínico/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transducción de Señal , Fertilización
14.
Nat Commun ; 14(1): 5331, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37658077

RESUMEN

The ideal mechanical properties and behaviors of materials without the influence of defects are of great fundamental and engineering significance but considered inaccessible. Here, we use single-atom-thin isotopically pure hexagonal boron nitride (hBN) to demonstrate that two-dimensional (2D) materials offer us close-to ideal experimental platforms to study intrinsic mechanical phenomena. The highly delicate isotope effect on the mechanical properties of monolayer hBN is directly measured by indentation: lighter 10B gives rise to higher elasticity and strength than heavier 11B. This anomalous isotope effect establishes that the intrinsic mechanical properties without the effect of defects could be measured, and the so-called ultrafine and normally neglected isotopic perturbation in nuclear charge distribution sometimes plays a more critical role than the isotopic mass effect in the mechanical and other physical properties of materials.

15.
Phys Rev Lett ; 130(22): 226501, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37327423

RESUMEN

The ultrafast electronic structures of the charge density wave material 1T-TiSe_{2} were investigated by high-resolution time- and angle-resolved photoemission spectroscopy. We found that the quasiparticle populations drove ultrafast electronic phase transitions in 1T-TiSe_{2} within 100 fs after photoexcitation, and a metastable metallic state, which was significantly different from the equilibrium normal phase, was evidenced far below the charge density wave transition temperature. Detailed time- and pump-fluence-dependent experiments revealed that the photoinduced metastable metallic state was a result of the halted motion of the atoms through the coherent electron-phonon coupling process, and the lifetime of this state was prolonged to picoseconds with the highest pump fluence used in this study. Ultrafast electronic dynamics were well captured by the time-dependent Ginzburg-Landau model. Our work demonstrates a mechanism for realizing novel electronic states by photoinducing coherent motion of atoms in the lattice.


Asunto(s)
Electrones , Movimiento (Física) , Espectroscopía de Fotoelectrones
16.
Adv Mater ; 35(32): e2212112, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37326574

RESUMEN

The axial orientation of molecular chains always results in an increase in fiber strength and a decrease in toughness. Here, taking inspiration from the skin structure, artificial spider silk with a buckled sheath-core structure is developed, with mechanical strength and toughness reaching 1.61 GPa and 466 MJ m-3 , respectively, exceeding those of Caerostris darwini silk. The buckled structure is achieved by nano-pulley combing of polyrotaxane hydrogel fibers through cyclic stretch-release training, which exhibits axial alignment of the polymer chains in the fiber core and buckling in the fiber sheath. The artificial spider silk also exhibits excellent supercontraction behavior, achieving a work capacity of 1.89 kJ kg-1 , and an actuation stroke of 82%. This work provides a new strategy for designing high-performance and intelligent fiber materials.


Asunto(s)
Seda , Arañas , Animales , Seda/química , Estrés Mecánico
17.
J Phys Chem Lett ; 14(26): 6099-6109, 2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37364134

RESUMEN

Herein, a simple two-step synthetic method was developed for the synthesis of NiFe2O4 nano-microrods supported on Ketjenblack carbon (NiFe2O4/KB). A sodium tartrate-assisted hydrothermal method was employed for the synthesis of a NiFe-MOF/KB precursor, which was then pyrolyzed under N2 at 500 °C to yield NiFe2O4/KB. Benefiting from the presence of high-valence Ni3+ and Fe3+, high conductivity, and a large electrochemically active surface area, NiFe2O4/KB delivered outstanding OER electrocatalytic performance under alkaline conditions, including a very low overpotential of 258 mV (vs RHE) at 10 mA cm-2, a small Tafel slope of 43.01 mV dec-1, and excellent durability in 1.0 M KOH. Density functional theory calculations verified the superior alkaline OER electrocatalytic activity of NiFe2O4 to IrO2. While both catalysts possessed a similar metallic ground state, NiFe2O4 offered a lower energy barrier in the rate-determining OER step (*OOH → O2) compared to IrO2, resulting in faster OER kinetics.

18.
Macromol Rapid Commun ; 44(23): e2300275, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37344253

RESUMEN

The twistocaloric effect is attributed to the change in entropy of the material driven by torsional stress. It is responsible for the torsional refrigeration of fiber materials that has been widely exploited as one of the solid-state cooling techniques with high efficiency and low volume change rate. The lack of theories and mathematical models of twistocaloric effect, however, limits broad applications of torsional refrigeration. In this work, a twistocaloric model is established to capture the relationship between twist density and temperature variation of natural rubber fibers and thermoplastic elastomer yarns. An experimental setup consisting torsion actuator and torque sensor coupled with a temperature measurement system is built to validate the model. Using the Maxwell relationship, twistocaloric coefficient is measured by quantifying the thermal effect induced by torsion under shear strain. The experimental characterization of the twistocaloric effect in natural rubber fiber and thermoplastic elastomer yarn are consistent with the theoretical predictions.


Asunto(s)
Elastómeros , Goma , Temperatura , Frío , Modelos Teóricos
19.
J Sep Sci ; 46(16): e2201048, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37155296

RESUMEN

Cinobufacini injection is commonly used in the clinical treatment of tumors and hepatitis B, but the quality is uneven. Currently, the main focus of its quality assessment is on steroids and alkaloids. Based on a previous study, we screened four peptides with high reproducibility, responsiveness, and specificity. This research was the first to develop an ultra-high-performance liquid chromatography/triple quadrupole mass spectrometry approach for evaluating the quality of cinobufacini preparations from the peptide perspective. In this study, we have identified 230 peptides in cinobufacini injection by Q-Exactive mass spectrometry, which contains species-specific peptides. Then, we used ultra-high-performance liquid chromatography/triple quadrupole mass spectrometry to establish a quantitative method for species-specific peptides and carried out method validation. The result revealed that four peptides were linear in a specific range, and had great reproducibility, accuracy, and stability. Eventually, we evaluated the quality of eight batches of cinobufacini injections and 26 batches of toad skins using the total content of target peptides as the criterion. The outcomes demonstrated that the quality of cinobufacini injection is generally stable and the toad skin from Shandong is of the best quality. In conclusion, the quantitative approach that focuses on peptides will offer innovative perspectives on assessing the quality of cinobufacini preparations.


Asunto(s)
Péptidos , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados , Espectrometría de Masas/métodos
20.
J Geriatr Cardiol ; 20(4): 293-308, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37122986

RESUMEN

BACKGROUND: Butylphthalide (NBP) and edaravone (EDV) injection are common acute ischemic stroke medications in China, but there is a lack of large real-world safety studies on them. This study aimed to determine the incidence of adverse events, detect relevant safety signals, and assess the risk factors associated with these medications in real-world populations. METHODS: In this study, data of acute ischemic stroke patients were extracted from the electronic medical record database of six tertiary hospitals between January 2019 and August 2021. Baseline confounders were eliminated using propensity score matching. The drugs' safety was estimated by comparing the results of 24 laboratory tests standards on liver function, kidney function, lipid level, and coagulation function. The drugs' relative risk was estimated by logistic regression. A third group with patients who did not receive NBP or EDV was constructed as a reference. Prescription sequence symmetry analysis was used to evaluate the associations between adverse events and NBP and EDV, respectively. RESULTS: 81,292 patients were included in this study. After propensity score matching, the NBP, EDV, and third groups with 727 patients in each group. Among the 15 test items, the incidence of adverse events was lower in the NBP group than in the EDV group, and the differences were statistically significant. The multivariate logistic regression equation revealed that NBP injection was not a promoting factor for abnormal laboratory test results, whereas EDV had statistically significant effects on aspartate transaminase, low-density lipoprotein cholesterol and total cholesterol. Prescription sequence symmetry analysis showed that NBP had a weak correlation with abnormal platelet count. EDV had a positive signal associated with abnormal results in gamma-glutamyl transferase, alanine aminotransferase, aspartate aminotransferase, prothrombin time, and platelet count. CONCLUSIONS: In a large real-world population, NBP has a lower incidence of adverse events and a better safety profile than EDV or other usual medications.

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