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Laser-based direct energy deposition (DED-LB/M) has been a promising option for the surface repair of structural aluminum alloys due to the advantages it offers, including a small heat-affected zone, high forming accuracy, and adjustable deposition materials. However, the unequal powder particle size during powder-based DED-LB/M can cause unstable flow and an uneven material flow rate per unit of time, resulting in defects such as pores, uneven deposition layers, and cracks. This paper presents a multiscale, multiphysics numerical model to investigate the underlying mechanism during the powder-based DED-LB/M surface repair process. First, the worn surfaces of aluminum alloy components with different flaw shapes and sizes were characterized and modeled. The fluid flow of the molten pool during material deposition on the worn surfaces was then investigated using a model that coupled the mesoscale discrete element method (DEM) and the finite volume method (FVM). The effect of flaw size and powder supply quantity on the evolution of the molten pool temperature, morphology, and dynamics was evaluated. The rapid heat transfer and variation in thermal stress during the multilayer DED-LB/M process were further illustrated using a macroscale thermomechanical model. The maximum stress was observed and compared with the yield stress of the adopted material, and no relative sliding was observed between deposited layers and substrate components.
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BACKGROUND: Limited data regarding the correlation between oxidative balance score (OBS) and hyperuricemia highlights the necessity for thorough investigations. This study aims to examine the link between OBS, which incorporates dietary and lifestyle factors, and the occurrence of hyperuricemia. METHODS: We conducted a cross-sectional study involving 13,636 participants from the 2007-2018 National Health and Nutrition Examination Survey (NHANES). The oxidative balance score (OBS) was determined based on four lifestyle factors and sixteen dietary nutrients. We assessed the levels of serum uric acid (SUA) and the occurrence of hyperuricemia as outcomes. Weighted logistic regression and linear models were used for statistical analysis, using Restricted Cubic Splines (RCS) to examine potential nonlinear associations. Subgroup analysis and sensitivity assessments were performed to identify any variations and ensure the robustness of the findings. RESULTS: Higher OBS was consistently correlated with decreased SUA levels and a reduced prevalence of hyperuricemia. RCS highlighted a significant negative nonlinear association, particularly in females. Subgroup analysis revealed gender-based differences and interactive correlation, providing additional insights regarding OBS and hyperuricemia relationship. CONCLUSION: This study underscores a robust negative correlation between OBS and SUA levels as well as the incidence of hyperuricemia, emphasizing the importance of dietary and lifestyle factors. Incorporating RCS, subgroup analysis, and sensitivity assessments enhances the depth of our findings, providing valuable insights for further research.
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Dieta , Hiperuricemia , Estilo de Vida , Encuestas Nutricionales , Ácido Úrico , Humanos , Hiperuricemia/sangre , Hiperuricemia/epidemiología , Femenino , Masculino , Estudios Transversales , Encuestas Nutricionales/métodos , Encuestas Nutricionales/estadística & datos numéricos , Persona de Mediana Edad , Adulto , Ácido Úrico/sangre , Dieta/métodos , Dieta/estadística & datos numéricos , Estrés Oxidativo , Prevalencia , AncianoRESUMEN
PURPOSE: Diabetic neuropathy (DN) is a notable complication of diabetes mellitus. The potential involvement of miR-146a in DN regulation is presently under investigation. Metformin, a commonly prescribed medication for diabetes, is the primary therapeutic intervention. This study aimed to unveil the potential protective effects of metformin on diabetic neuropathy and explore the mechanisms underlying its action. METHOD: Six-weeks male Sprague Dawley rats (n = 40) were randomly divided into 5 groups. The rat model of diabetic neuropathy (DN) was established by administering streptozotocin (STZ). To investigate the effects on the sciatic nerve and resident Schwann cells (RSCs), metformin and miR-146a mimics were administered, and our research explored the potential underlying mechanism. RESULT: The sciatic nerve samples obtained from diabetic rats exhibited noticeable morphological damage, accompanied by decreased miR-146a expression (2.61 ± 0.11 vs 5.0 ± 0.3, p < 0.01) and increased inflammation levels (p65: 1.89 ± 0.04 vs 0.82 ± 0.05, p < 0.01; TNF-α: 0.93 ± 0.03 vs 0.33 ± 0.03, p < 0.01). Notably, the administration of metformin effectively ameliorated the structural alterations in the sciatic nerve by suppressing the inflammatory pathway (p65: 1.15 ± 0.05 vs 1.89 ± 0.04, p < 0.01; TNF-α: 0.67 ± 0.04 vs 0.93 ± 0.03, p < 0.01) and reducing oxidative stress (NO: 0.062 ± 0.004 vs 0.154 ± 0.004umol/mg, p < 0.01; SOD: 3.08 ± 0.09 vs 2.46 ± 0.09 U/mg, p < 0.01). The miR-146a mimics intervention group exhibited comparable findings. CONCLUSION: This study's findings implied that metformin can potentially mitigate diabetic neuropathy in rats through the modulation of miR-146a expression.
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Diabetes Mellitus Experimental , Neuropatías Diabéticas , Metformina , MicroARNs , Estrés Oxidativo , Ratas Sprague-Dawley , Regulación hacia Arriba , Animales , Metformina/farmacología , MicroARNs/genética , MicroARNs/metabolismo , Neuropatías Diabéticas/patología , Neuropatías Diabéticas/metabolismo , Neuropatías Diabéticas/tratamiento farmacológico , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Nervio Ciático/efectos de los fármacos , Nervio Ciático/patología , Nervio Ciático/metabolismo , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Inflamación/tratamiento farmacológico , Células de Schwann/efectos de los fármacos , Células de Schwann/metabolismo , Células de Schwann/patologíaRESUMEN
BACKGROUND: Patients with early esophageal cancer (EC) receive individualized therapy based on their lymph node metastasis (LNM) and distant metastasis (DM) status; however, deficiencies in current clinical staging techniques and the issue of cost-effectiveness mean LNM and DM often go undetected preoperatively. We aimed to develop three clinical models to predict the likelihood of LNM, DM, and prognosis in patients with early EC. METHOD: The Surveillance, Epidemiology, and End Results database was queried for T1 EC patients from 2004 to 2015. Multivariable logistic regression and Cox proportional hazards models were used to recognize the risk factors of LNM and DM, predict overall survival (OS), and develop relevant nomograms. Receiver operating characteristic (ROC)/concordance index and calibration curves were used to evaluate the discrimination and accuracy of the three nomograms. Decision curve analyses (DCAs), clinical impact curves, and subgroups based on model scores were used to determine clinical practicability. RESULTS: The area under the curve of the LNM and DM nomograms were 0.668 and 0.807, respectively. The corresponding C-index of OS nomogram was 0.752. Calibration curves and DCA showed an effective predictive accuracy and clinical applicability. In patients with T1N0M0 EC, surgery alone (p < 0.01) proved a survival advantage. Chemotherapy and radiotherapy indicated a better prognosis in the subgroup analysis for T1 EC patients with LNM or DM. CONCLUSIONS: We created three nomograms to predict the likelihood of LNM, DM, and OS probability in patients with early EC using a generalizable dataset. These useful visual tools could help clinical physicians deliver appropriate perioperative care.
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Neoplasias Esofágicas , Humanos , Metástasis Linfática , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/terapia , Investigación , Nomogramas , Ganglios LinfáticosRESUMEN
Objective:To investigate the incidence and risk factors of skip lateral cervical lymph node metastasis in patients with papillary thyroid carcinomaï¼PTCï¼. Methods:The clinical and pathological data of 85 patients with PTC who underwent total thyroidectomy plus central and lateral neck dissection in the Department of Otolaryngology Head and Neck Surgery, the First Affiliated Hospital of Hebei North University from January 2018 to January 2022 were analyzed retrospectively. SPSS 26.0 software was used to process the data, and univariate and multivariate analysis were performed to assess the relationships between skip lateral cervical lymph node metastasis and clinicopathological characteristics. Results:There were 31 casesï¼36.5%ï¼ of skipped lateral cervical lymph node metastasis. Univariate analysis showed that the largest tumor diameter ≤5 mmï¼P=0.006ï¼ and the tumor located in the upper pole of the thyroidï¼P=0.002ï¼ were associated with the occurrence of skip lateral cervical lymph node metastasis in patients with PTC. Most of the skip metastases involved a single areaï¼18/31, 58.1%ï¼, of which area â ¢ was most likely to be involvedï¼10/31, 32.3%ï¼, followed by area â ¡ï¼5/31, 16.1%ï¼. The results of binary logistic analysis showed that tumor diameter less than 5 mmï¼OR 7.800, 95%CI 1.710-21.394, P=0.005ï¼ and tumor at the upper pole of the glandï¼OR 4.060, 95%CI 1.468-11.235, P=0.007ï¼ were independent risk factors of skip lateral cervical lymph node metastasis in PTC patients. Conclusion:PTC patients with tumor diameter ≤5 mm and tumor located in the upper pole of the gland are more prone to skip lateral cervical lymph node metastasis. When the diameter of the tumor is less than 5 mm and the tumor is located at the upper pole of the gland, careful evaluation should be made before operation, even in the absence of central lymph node metastasis, attention should be paid to the possibility of lateral cervical lymph node metastasis.