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1.
Ann Hematol ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709259

RESUMEN

Cardiotoxicity in children is a potentially fatal complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT); therefore, early identification of risk factors can improve patient prognosis. However, there are few data on the clinical characteristics of early-stage cardiotoxicity in children after allo-HSCT. We conducted a retrospective single-center study of pediatric patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) between January 2016 and December 2022 at the Children's Hospital Affiliated with Chongqing Medical University to evaluate the clinical characteristics of early cardiac events (ECEs) after allo-HSCT and their impact on survival outcomes. We enrolled 444 patients who underwent allo-HSCT-304 males (68%) and 140 females (32%)-with a median age of 3.3 years (1.8-6.5 years) at transplantation. We found that 73 patients (16.4%) had ECEs after allo-HSCT. The ECEs included valvular disease (n = 46), pericardial effusion (n = 38), arrhythmia (n = 9), heart failure (n = 16), and dilated cardiomyopathy (n = 1). Female sex, age ≥ 6 years, body mass index (BMI) < 16 kg/m2 and HLA-type mismatches were risk factors for ECEs. We designed a stratified cardiac risk score that included these risk factors, and the higher the score was, the greater the cumulative incidence of ECEs. The occurrence of an ECE was closely associated with a lower overall survival (OS) rate and greater nonrelapse mortality (NRM). In addition, stratified analysis based on the number of combined ECEs showed that the greater the number of combined ECEs was, the more significant the negative impact on OS rates.

2.
Asian J Androl ; 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38445955

RESUMEN

ABSTRACT: Failure of oocyte activation, including polyspermy and defects in pronuclear (PN) formation, triggers early embryonic developmental arrest. Many studies have shown that phospholipase C zeta 1 ( PLCZ1 ) mutations cause failure of PN formation following intracytoplasmic sperm injection (ICSI); however, whether PLCZ1 mutation is associated with polyspermy during in vitro fertilization (IVF) remains unknown. Whole-exome sequencing (WES) was performed to identify candidate mutations in couples with primary infertility. Sanger sequencing was used to validate the mutations. Multiple PLCZ1 -mutated sperm were injected into human and mouse oocytes to explore whether PN formation was induced. Assisted oocyte activation (AOA) after ICSI was performed to overcome the failure of oocyte activation. We identified three PLCZ1 mutations in three patients who experienced polyspermy during IVF cycles, including a novel missense mutation c.1154C>T, p.R385Q. PN formation failure was observed during the ICSI cycle. However, injection of multiple PLCZ1 -mutated sperm induced PN formation, suggesting that the Ca 2+ oscillations induced by the sperm exceeded the necessary threshold for PN formation. AOA after ICSI enabled normal fertilization, and all patients achieved successful pregnancies. These findings expand the mutational spectrum of PLCZ1 and suggest an important role for PLCZ1 in terms of blocking polyspermy. Furthermore, this study may benefit genetic diagnoses in cases of abnormal fertilization and provide potential appropriate therapeutic measures for these patients with sperm-derived polyspermy.

3.
World J Diabetes ; 15(2): 220-231, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38464364

RESUMEN

BACKGROUND: The effects of viral hepatitis (VH) on type 2 diabetes (T2D) remain controversial. AIM: To analyze the causal correlation between different types of VH and T2D using Mendelian randomization (MR). METHODS: Single nucleotide polymorphisms of VH, chronic hepatitis B (CHB), chronic hepatitis C (CHC) and T2D were obtained from the BioBank Japan Project, European Bioinformatics Institute, and FinnGen. Inverse variance weighted, MR-Egger, and weighted median were used to test exposure-outcome associations. The MR-Egger intercept analysis and Cochran's Q test were used to assess horizontal pleiotropy and heterogeneity, respectively. Leave-one-out sensitivity analysis was used to evaluate the robustness of the MR analysis results. RESULTS: The MR analysis showed no significant causal relationship between VH and T2D in Europeans [odds ratio (OR) = 1.028; 95% confidence interval (CI): 0.995-1.062, P = 0.101]. There was a negative causal association between CHB and T2D among East Asians (OR = 0.949; 95%CI: 0.931-0.968, P < 0.001), while there was no significant causal association between CHC and T2D among East Asians (OR = 1.018; 95%CI: 0.959-1.081, P = 0.551). Intercept analysis and Cochran's Q test showed no horizontal pleiotropy or heterogeneity (P > 0.05). Sensitivity analysis showed that the results were robust. CONCLUSION: Among East Asians, CHB is associated with a reduced T2D risk, but this association is limited by HBV load and cirrhosis. Although VH among Europeans and CHC among East Asians are not associated with the risk of T2D, focusing on blood glucose in patients with CHC is still relevant for the early detection of T2D induced by CHC-mediated pathways of hepatic steatosis, liver fibrosis, and cirrhosis.

4.
ACS Omega ; 9(7): 8092-8102, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38405486

RESUMEN

At present, light transmission, energy saving, environmental protection, and UV-shielding materials are very important for optimizing indoor living environment. Here, a fluorescent transparent wood (FTW) with UV-shielding function was prepared by encapsulating a carbon quantum dot and epoxy resin into a delignification wood template. FTW exhibits excellent optical transmittance (about 91%), water absorption stability (weight gain rate less than 9%), longitudinal tensile strength (139 MPa), and UV-shielding properties. Due to the photoluminescence characteristics of the carbon quantum dot and the natural cellulose skeleton of wood, FTW can show uniform luminescence under ultraviolet lamps. At the same time, it has remarkable UV-shielding performance. This kind of photoluminescent transparent wood with a UV-shielding function also has the potential to be applied to fields such as electromagnetic shielding and harmful gas detection.

5.
Nature ; 626(8000): 779-784, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38383626

RESUMEN

Moiré superlattices formed by twisted stacking in van der Waals materials have emerged as a new platform for exploring the physics of strongly correlated materials and other emergent phenomena1-5. However, there remains a lack of research on the mechanical properties of twisted-layer van der Waals materials, owing to a lack of suitable strategies for making three-dimensional bulk materials. Here we report the successful synthesis of a polycrystalline boron nitride bulk ceramic with high room-temperature deformability and strength. This ceramic, synthesized from an onion-like boron nitride nanoprecursor with conventional spark plasma sintering and hot-pressing sintering, consists of interlocked laminated nanoplates in which parallel laminae are stacked with varying twist angles. The compressive strain of this bulk ceramic can reach 14% before fracture, about one order of magnitude higher compared with traditional ceramics (less than 1% in general), whereas the compressive strength is about six times that of ordinary hexagonal boron nitride layered ceramics. The exceptional mechanical properties are due to a combination of the elevated intrinsic deformability of the twisted layering in the nanoplates and the three-dimensional interlocked architecture that restricts deformation from propagating across individual nanoplates. The advent of this twisted-layer boron nitride bulk ceramic opens a gate to the fabrication of highly deformable bulk ceramics.

6.
Nature ; 626(7997): 79-85, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38172640

RESUMEN

Grain boundaries (GBs), with their diversity in both structure and structural transitions, play an essential role in tailoring the properties of polycrystalline materials1-5. As a unique GB subset, {112} incoherent twin boundaries (ITBs) are ubiquitous in nanotwinned, face-centred cubic materials6-9. Although multiple ITB configurations and transitions have been reported7,10, their transition mechanisms and impacts on mechanical properties remain largely unexplored, especially in regard to covalent materials. Here we report atomic observations of six ITB configurations and structural transitions in diamond at room temperature, showing a dislocation-mediated mechanism different from metallic systems11,12. The dominant ITBs are asymmetric and less mobile, contributing strongly to continuous hardening in nanotwinned diamond13. The potential driving forces of ITB activities are discussed. Our findings shed new light on GB behaviour in diamond and covalent materials, pointing to a new strategy for development of high-performance, nanotwinned materials.

7.
World J Gastroenterol ; 29(42): 5781-5799, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-38075850

RESUMEN

BACKGROUND: As an emerging potential risk factor for gastric cancer, autoimmune gastritis (AIG) has garnered increasing attention from researchers. AIM: To analyze the research overview and popular topics in the field of AIG using bibliometrics. METHODS: Relevant publications on AIG in the Web of Science Core Collection were collated, and data visualization and analysis of the number of publications, countries, institutions, journals, authors, keywords, and citations were performed using software such as VOSviewer, CiteSpace, and Scimago Graphic. RESULTS: In total, 316 relevant articles were included in the analysis. From 2015 to 2022, the number of publications increased annually. The countries, institutions, authors, and journals with the highest number of publications in this field were Italy, Monash University, Toh BH, and Internal Medicine. The main keywords used in this field of research were pathogenesis, Helicobacter pylori, autoantibody, parietal cell antibody, atrophic gastritis, classification, diagnosis, autoimmune disease, risk, cancer, gastric cancer, vitamin B12 deficiency, and pernicious anemia. The following directions may be popular for future research: (1) The role of Helicobacter pylori in the pathogenesis of AIG; (2) diagnostic criteria for AIG and reference values for serum antibodies; (3) comorbidity mechanisms between AIG and other autoimmune diseases; (4) specific risks of AIG complicating gastric and other cancers; and (5) the role of vitamin B12 supplementation in patients with early-stage AIG. CONCLUSION: This bibliometric analysis reported on popular topics and emerging trends in AIG, with diagnosis and prognosis being research hotspots in this field.


Asunto(s)
Enfermedades Autoinmunes , Gastritis Atrófica , Gastritis , Neoplasias Gástricas , Humanos , Autoanticuerpos , Bibliometría , Gastritis/epidemiología , Gastritis/diagnóstico , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/complicaciones
8.
Hematology ; 28(1): 2245259, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37551721

RESUMEN

OBJECTIVES: The clinical characteristics, risk factors and survival prognosis of pericardial effusion (PE) after haematopoietic stem cell transplantation (HSCT) in children were investigated. METHODS: Clinical data of children who underwent HSCT at the Children's Hospital Affiliated with Chongqing Medical University from January 2016 to December 2022 were analysed retrospectively. Cox proportional hazards regression and the Kaplan-Meier method were used to analyse the risk factors for post-HSCT PE and its impact on outcomes, respectively. RESULTS: We enrolled 452 patients with HSCT: 307 males and 145 females, with a median age of 3.4 (1.8 to 6.5) years at transplantation. Forty-five patients (10%) had PE within a median time of 25 (10.5 to 44) days, 42 (93%) within 100 days. Three patients with large PE were treated with pericardiocentesis and drainage, while the others were treated conservatively. Of the 45 patients with PE, 24 survived, and their PE disappeared after treatment. Graft-versus-host disease (GVHD) grade, abnormal pre-HSCT electrocardiogram, hepatic veno-occlusive disease (HVOD), pulmonary infection and Epstein-Barr virus (EBV) infection were risk factors for PE. The overall survival (OS) rates at 1, 3, and 5 years were 86.0%, 84.2%, and 82.3%, respectively. PE had a significant negative effect on OS after HSCT (P < 0.0001). Particularly, one patient with large PE died of pericardial tamponade. CONCLUSIONS: Post-HSCT PE usually occurred within 100 days. GVHD grade, abnormal pre-HSCT electrocardiogram, HVOD, pulmonary infection and EBV infection were closely related to PE. PE had a significant negative effect on OS rate.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Derrame Pericárdico , Masculino , Femenino , Humanos , Niño , Preescolar , Derrame Pericárdico/epidemiología , Derrame Pericárdico/etiología , Estudios Retrospectivos , Infecciones por Virus de Epstein-Barr/etiología , Herpesvirus Humano 4 , Factores de Riesgo , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos
9.
PLoS One ; 18(7): e0286208, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37471399

RESUMEN

BACKGROUND: Cognitive flexibility (CF) enables individuals to readily shift from one concept or mode of practice/thoughts to another in response to changes in the environment and feedback, making CF vital to optimise success in obtaining goals. However, how CF relates to other executive functions (e.g., working memory, response inhibition), mental abilities (e.g., creativity, literacy, numeracy, intelligence, structure learning), and social factors (e.g., multilingualism, tolerance of uncertainty, perceived social support, social decision-making) is less well understood. The current study aims to (1) establish the construct validity of CF in relation to other executive function skills and intelligence, and (2) elucidate specific relationships between CF, structure learning, creativity, career decision making and planning, and other life skills. METHODS: This study will recruit up to 400 healthy Singaporean young adults (age 18-30) to complete a wide range of cognitive tasks and social questionnaires/tasks. The richness of the task/questionnaire battery and within-participant administration enables us to use computational modelling and structural equation modelling to examine connections between the latent constructs of interest. SIGNIFICANCE AND IMPACT: The current study is the first systematic investigation into the construct validity of CF and its interrelationship with other important cognitive skills such as learning and creativity, within an Asian context. The study will further explore the concept of CF as a non-unitary construct, a novel theoretical proposition in the field. The inclusion of a structure learning paradigm is intended to inform future development of a novel intervention paradigm to enhance CF. Finally, the results of the study will be useful for informing classroom pedagogy and the design of lifelong learning policies and curricula, as part of the wider remit of the Cambridge-NTU Centre for Lifelong Learning and Individualised Cognition (CLIC).


Asunto(s)
Cognición , Función Ejecutiva , Humanos , Adulto Joven , Adolescente , Adulto , Cognición/fisiología , Aprendizaje , Memoria a Corto Plazo/fisiología , Creatividad
10.
Environ Sci Technol ; 57(19): 7516-7525, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37130379

RESUMEN

The simultaneous precipitation of (Fe, Cr)(OH)3 nanoparticles in solution (homogeneous) and on soil surfaces (heterogeneous), which controls Cr transport in soil and aquatic systems, was quantified for the first time in the presence of model surfaces, i.e., bare and natural organic matter (NOM)-coated SiO2 and Al2O3. Various characterization techniques were combined to explore the surface-ion-precipitate interactions and the controlling mechanisms. (Fe, Cr)(OH)3 accumulation on negatively charged SiO2 was mainly governed by electrostatic interactions between hydrolyzed ion species or homogeneous (Fe, Cr)(OH)3 and surfaces. The elevated pH through protonation of Al2O3 surface hydroxyls resulted in higher Cr/Fe ratios in both homogeneous and heterogeneous coprecipitates. Due to ignorable NOM adsorption onto SiO2, the amounts of (Fe, Cr)(OH)3 precipitates on bare/NOM-SiO2 were similar; contrarily, attributed to favored NOM adsorption onto Al2O3 and consequently carboxyl association with metal ions or (Fe, Cr)(OH)3 nanoparticles, remarkably more heterogeneous precipitates harvested on NOM-Al2O3 than bare-Al2O3. With the same solution supersaturation, the total amounts of homogeneous and heterogeneous precipitates were similar irrespective of the substrate type. With lower pH, decreased electrostatic forces between substrates and precipitates shifted (Fe, Cr)(OH)3 distribution from heterogeneous to homogeneous phases. The quantitative knowledge of (Fe, Cr)(OH)3 distribution and the controlling mechanisms can assist in better Cr sequestration in natural and engineered settings.


Asunto(s)
Nanopartículas , Suelo , Dióxido de Silicio , Metales , Nanopartículas/química , Concentración de Iones de Hidrógeno , Adsorción
11.
Arch Oral Biol ; 150: 105691, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37043987

RESUMEN

OBJECTIVE: To study the effect of EGCG on tooth movement and root resorption during orthodontic treatment in rats. METHODS: A total of thirty six male Wistar rats were randomly and equally divided into three groups: control, 50 mg/kg EGCG, and 100 mg/kg EGCG. During the experiment, the subjects were submitted to an orthodontic tooth movement (OTM) model, rats in the experimental groups were given the corresponding dose of EGCG, while rats in the control group were administrated with an equal volume of normal saline solution by gavage. After 14 days of OTM, the rats were sacrificed by transcardial perfusion. Micro-CT of rat maxillaes was taken to analyze OTM distance and root resorption. The maxillary samples were prepared as histological sections for H&E staining, tartrate-resistant acid phosphatase (TRAP) staining and immunohistochemical (IHC) staining to be observed and analyzed. RESULTS: The OTM distance and root resorption of rats in the dosed group decreased, and the number of TRAP positive cells in their periodontium decreased significantly. The expression level of RANKL was decreased in the EGCG group compared to the control group, while that of OPG, OCN and Runx2 was increased. Effects were more pronounced in 100 mg/kg group than in 50 mg/kg group. CONCLUSION: EGCG reduces OTM and orthodontic induced root resorption (OIRR) in rats, and is able to attenuate osteoclastogenesis on the pressure side and promote osteogenesis on the tension side.


Asunto(s)
Resorción Radicular , Ratas , Masculino , Animales , Resorción Radicular/tratamiento farmacológico , Ratas Wistar , Osteoclastos , Técnicas de Movimiento Dental , , Raíz del Diente
12.
Micromachines (Basel) ; 14(2)2023 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-36838128

RESUMEN

The preparation of micro/nano periodic surface structures using femtosecond laser machining technology has been the academic frontier and hotspot in recent years. The formation and evolution of micro/nano periodic ripples were investigated on 2205 stainless steel machined by femtosecond laser. Using single spot irradiation with fixed laser fluences and various pulse numbers, typical ripples, including nano HSFLs (‖), nano LSFLs (⟂), nano HSFLs (⟂) and micro grooves (‖), were generated one after another in one test. The morphologies of the ripples were analyzed, and the underlying mechanisms were discussed. It was found that the nano holes/pits presented at all stages could have played a key role in the formation and evolution of micro/nano periodic ripples. A new kind of microstructure, named the pea pod-like structure here, was discovered, and it was suggested that the formation and evolution of the micro/nano periodic ripples could be well explained by the pea pod-like structure model.

13.
Transplant Cell Ther ; 29(4): 240.e1-240.e10, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36634739

RESUMEN

Heart failure (HF) is an uncommon but serious cardiovascular complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Unfortunately, knowledge about early mortality prognostic factors in patients with HF after allo-HSCT is limited, and an easy-to-use prognostic model is not available. This study aimed to develop and validate a clinical-biomarker prognostic model capable of predicting HF mortality following allo-HSCT that uses a combination of variables readily available in clinical practice. To investigate this issue, we conducted a retrospective analysis at our center with 154 HF patients who underwent allo-HSCT between 2008 and 2021. The patients were separated according to the time of transplantation, with 100 patients composing the derivation cohort and the other 54 patients composing the external validation cohort. We first calculated the univariable association for each variable with 2-month mortality in the derivation cohort. We then included the variables with a P value <.1 in univariate analysis as candidate predictors in the multivariate analysis using a backward stepwise logistic regression model. Variables remaining in the final model were identified as independent prognostic factors. To predict the prognosis of HF, a scoring system was established, and scores were assigned to the prognostic factors based on the regression coefficient. Finally, 4 strongly significant independent prognostic factors for 2-month mortality from HF were identified using multivariable logistic regression methods with stepwise variable selection: pulmonary infection (P = .005), grade III to IV acute graft-versus-host disease (severe aGVHD; P = .033), lactate dehydrogenase (LDH) >426 U/L (P = .049), and brain natriuretic peptide (BNP) >1799 pg/mL (P = .026). A risk grading model termed the BLIPS score (for BNP, LDH, cardiac troponin I, pulmonary infection, and severe aGVHD) was constructed according to the regression coefficients. The validated internal C-statistic was .870 (95% confidence interval [CI], .798 to .942), and the external C-statistic was .882 (95% CI, .791-.973). According to the calibration plots, the model-predicted probability correlated well with the actual observed frequencies. The clinical use of the prognostic model, according to decision curve analysis, could benefit HF patients. The BLIPS model in our study can serve to identify HF patients at higher risk for mortality early, which might aid designing timely targeted therapies and eventually improving patients' survival and prognosis.


Asunto(s)
Insuficiencia Cardíaca , Trasplante de Células Madre Hematopoyéticas , Humanos , Adulto , Pronóstico , Estudios Retrospectivos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/métodos , Biomarcadores , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/etiología
14.
Dig Dis Sci ; 68(4): 1280-1291, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36002676

RESUMEN

BACKGROUND: Tyrosine kinase inhibitors are currently the most widely studied targeted therapies for gastric cancer. As a triple tyrosine inhibitor, nintedanib can alleviate the progression of a variety of cancers, but it is poorly studied in gastric cancer. AIMS: To investigate the effect of nintedanib on gastric cancer. METHODS: This study investigated nintedanib's effect on gastric cancer autophagy in vivo and in vitro, and the activity and morphological changes of gastric cancer cells were detected by MTT and HE staining. Proliferation, migration, invasion, and EMT-related marker proteins of AGS and MKN-28 cells were detected. The effects of nintedanib on autophagy in gastric cancer cells were detected by acridine orange, immunofluorescence, and Western blotting assays. The regulation of nintedanib on STAT3 and Beclin1 was detected by qPCR and Western blotting assays. Subsequently, the effects of nintedanib on the tumor STAT3/Beclin1 pathway were verified by stably overexpressing STAT3 in gastric cancer cell lines and tumor-bearing experiments in nude mice. RESULTS: The results showed that nintedanib could inhibit gastric cancer cells' proliferation and EMT process. Meanwhile, autophagy was induced in AGS and MKN-28 cells, and the expression of autophagy-related protein Beclin1 was upregulated, and the phosphorylation level of STAT3 was downregulated. Nintedanib inhibited STAT3 phosphorylation and upregulated Beclin1 to inhibit tumor growth in gastric cancer cell lines with stable STAT3 overexpression and tumor-bearing experiments in nude mice. CONCLUSIONS: By inhibiting STAT3, nintedanib upregulated Beclin1 and caused autophagic death in gastric cancer cells.


Asunto(s)
Neoplasias Gástricas , Animales , Ratones , Beclina-1/genética , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Ratones Desnudos , Línea Celular Tumoral , Autofagia , Proliferación Celular , Apoptosis
15.
Adv Mater ; 35(50): e2204375, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36099908

RESUMEN

The observation of fracture behaviors in perfect and twinned B4 C crystals via in situ transmission electron microscopy (TEM) mechanical testing is reported. The crystal structure of the synthesized B4 C, composed of B11 C icosahedra connected by boron-deficient C-▫-C chains in a chemical formula of B11 C3 , is determined by state-of-the-art aberration-corrected scanning TEM. The in situ TEM observations reveal that cracking is preferentially initiated at the twin boundaries (TBs) in B4 C under both indentation and tension loading. The cracks then propagate along the TBs, thus resulting in the fracture of B4 C. These results are consistent with the theoretical calculations that show that TBs have a softening effect on B4 C with amorphous bands preferentially nucleated at the TBs. These findings elucidate the atomic arrangement and the role of planar defects in the failure of B4 C. Furthermore, they can guide the design of advanced superhard materials via planar defect control.

16.
Zhonghua Nan Ke Xue ; 29(9): 799-803, 2023 Sep.
Artículo en Chino | MEDLINE | ID: mdl-38639591

RESUMEN

OBJECTIVE: To explore the mechanism of Shenrong pills in improving oligoasthenospermia by inhibiting oxidative stress-induced Leydig cell apoptosis in mouse testis. METHODS: The oxidative stress model of mouse Leydig cells (TM3) was induced by 3% hydrogen peroxide (H2O2) of 600 µmol/L, and then TM3 cells were treated with 7.5%, 10% and 12.5% serum containing Shenrong pills, respectively. TM3 cells were divided into normal control group, model group, and low, medium and high dose groups of Shenrong pills containing serum. The cell viability of TM3 after treatment was detected by CCK-8 method, reactive oxygen species (ROS) were detected by DCFH probe method, and SOD-1, CAT, GSH-px, MDA and LPO in cell lysates were detected by ELISA method. The changes of apoptosis-related proteins Bcl-2, Bax in cell lysates were detected by Western Blot. RESULTS: After H2O2 treatment, compared with normal control group, cell viability was significantly decreased (P< 0.01), MDA and LPO contents were significantly increased (P<0.01), SOD-1, CAT and GSH-px contents were significantly decreased (P<0.01). Reactive oxygen species (ROS) were significantly increased, the relative expression ratio of Bcl-2 protein was significantly decreased (P<0.01, P<0.05), and the relative expression of Bax protein was increased. After the administration of Shenrong pills containing serum, the above indexes were reversed to varying degrees. CONCLUSION: Shenrong pills can resist oxidative stress, inhibit the apoptosis of TM3 cells in mice, maintain high levels of testosterone required for spermatogenic cells, and improve the sperm quality of mice with oligonasthenospermia.


Asunto(s)
Peróxido de Hidrógeno , Células Intersticiales del Testículo , Ratones , Animales , Masculino , Especies Reactivas de Oxígeno/metabolismo , Peróxido de Hidrógeno/farmacología , Semen/metabolismo , Estrés Oxidativo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/farmacología , Apoptosis
17.
Nanomaterials (Basel) ; 12(21)2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36364509

RESUMEN

The reinforcements represented by graphene nanoplatelets, graphite, and carbon nanotubes have demonstrated the great potential of carbon materials as reinforcements to enhance the mechanical properties of TiO2. However, it is difficult to successfully prepare TiO2-diamond composites because diamond is highly susceptible to oxidation or graphitization at relatively high sintering temperatures. In this work, the TiO2-diamond composites were successfully prepared using high-pressure sintering. The effect of diamond on the phase composition, microstructure, mechanical properties, and tribological properties was systemically investigated. Diamond can improve fracture toughness by the crack deflection mechanism. Furthermore, the addition of diamond can also significantly reduce the friction coefficient. The composite composed of 10 wt.% diamond exhibits optimum mechanical and tribological properties, with a hardness of 14.5 GPa, bending strength of 205.2 MPa, fracture toughness of 3.5 MPa∙m1/2, and a friction coefficient of 0.3. These results enlarge the family of titania-based composites and provide a feasible approach for the preparation of TiO2-diamond composites.

18.
Opt Express ; 30(12): 21184-21194, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-36224843

RESUMEN

High pattern fidelity is paramount to the performance of metalenses and metasurfaces, but is difficult to achieve using economic photolithography technologies due to low resolutions and limited process windows of diverse subwavelength structures. These hurdles can be overcome by photomask sizing or reshaping, also known as optical proximity correction (OPC). However, the lithographic simulators critical to model-based OPC require precise calibration and have not yet been specifically developed for metasurface patterning. Here, we demonstrate an accurate lithographic model based on Hopkin's image formulation and fully convolutional networks (FCN) to control the critical dimension (CD) patterning of a near-infrared (NIR) metalens through a distributed OPC flow using i-line photolithography. The lithographic model achieves an average ΔCD/CD = 1.69% due to process variations. The model-based OPC successfully produces the 260 nm CD in a metalens layout, which corresponds to a lithographic constant k1 of 0.46 and is primarily limited by the resolution of the photoresist. Consequently, our fabricated NIR metalens with a diameter of 1.5 mm and numerical aperture (NA) of 0.45 achieves a measured focusing efficiency of 64%, which is close to the calculated value of 69% and among the highest reported values using i-line photolithography.

19.
ACS Omega ; 7(29): 25822-25836, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35910162

RESUMEN

A Pt-nanocoated layer (thickness of approx. 10-20 nm) with Pt-O-Ce bonds was created through the water radiolysis reaction on a CeO x nanowire (NW), which was induced by electron beam irradiation to the mixed suspension of K2PtCl4 aqueous solution and the CeO x NW. In turn, when Pt-nanocoated CeO x NW/C (Pt/C ratio = 0.2) was used in the cathode layer of a membrane electrode assembly (MEA), both an improved fuel cell performance and stability were achieved. The fuel cell performance observed for the MEA using Pt-nanocoated CeO x NW/C with Pt-O-Ce bonds, which was prepared using the electron beam irradiation method, improved and maintained its performance (observed cell potential of approximately 0.8 V at 100 mW cm-2) from 30 to 140 h after the start of operation. In addition, the activation overpotential at 100 mA cm-2 (0.17 V) obtained for MEA using Pt-nanocoated CeO x NW/C was approximately half of the value at 100 mA cm-2 (0.35 V) of MEA using a standard Pt/C cathode. In contrast, the fuel cell performance (0.775 V at 100 mW cm-2 after 80 h of operation) of MEA using a nanosized Pt-loaded CeO x NW (Pt/C = 0.2), which was prepared using the conventional chemical reduction method, was lower than that of MEA using a Pt-nanocoated CeO x /C cathode and showed reduction after 80 h of operation. It is considered why the nanocoated layer having Pt-O-Ce bonds heterogeneously formed on the surface of the CeO x NW and the bare CeO2 surface consisting of Ce4+ cations would become unstable in an acidic atmosphere. Furthermore, when a conventional low-amount Pt/C cathode (Pt/C = 0.04) was used as the cathode layer of the MEA, its stable performance could not be measured after 80 h of operation as a result of flooding caused by a lowering of electrocatalytic activity on the Pt/C cathode in the MEA. In contrast, a low-amount Pt-nanocoated CeO x NW (Pt/C = 0.04) could maintain a low activation overpotential (0.22 V at 100 mA cm-2) of MEA at the same operation time. Our surface first-principles modeling indicates that the high quality and stable performance observed for the Pt-nanocoated CeO x NW cathode of MEA can be attributed to the formation of a homogeneous electric double layer on the sample. Since the MEA performance can be improved by examining a more effective method of electron beam irradiation to all surfaces of the sample, the present work result shows the usefulness of the electron beam irradiation method in preparing active surfaces. In addition, the quantum beam technology such as the electron beam irradiation method was shown to be useful for increasing both performance and stability of fuel cells.

20.
Atten Percept Psychophys ; 84(7): 2384-2407, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35199324

RESUMEN

The mean estimation task, which explicitly asks observers to estimate the mean feature value of multiple stimuli, is a fundamental paradigm in research areas such as ensemble coding and cue integration. The current study uses computational models to formalize how observers summarize information in mean estimation tasks. We compare model predictions from our Fidelity-based Integration Model (FIM) and other models on their ability to simulate observed patterns in within-trial weight distribution, across-trial information integration, and set-size effects on mean estimation accuracy. Experiments show non-equal weighting within trials in both sequential and simultaneous mean estimation tasks. Observers implicitly overestimated trial means below the global mean and underestimated trial means above the global mean. Mean estimation performance declined and stabilized with increasing set sizes. FIM successfully simulated all observed patterns, while other models failed. FIM's information sampling structure provides a new way to interpret the capacity limit in visual working memory and sub-sampling strategies. As a model framework, FIM offers task-dependent modeling for various ensemble coding paradigms, facilitating research synthesis across different studies in the literature.


Asunto(s)
Memoria a Corto Plazo , Percepción Visual , Humanos
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