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Life expectancy is increasing, leading to the continuous aging of the population in China. Enhancing the health status of the older population is crucial to achieving healthy aging. The primary objective of the PENG ZU Study on Healthy Aging in China (PENG ZU Cohort) is to understand the natural progression of health status among the aging Chinese population. Specifically, the PENG ZU cohort aims to identify and validate multidimensional aging markers, uncover the underlying mechanisms of systemic aging and functional decline, and develop novel strategies and measures to delay functional decline and adverse health outcomes, while maintaining overall good health. The PENG ZU cohort consists of 26,000 individuals aged 25 to 89 years from seven major geographical regions in China. Diversified data and biospecimens are collected according to standardized procedures at baseline and follow-up visits. Baseline recruitment for the PENG ZU cohort was completed in October 2021. The extensive analysis of multidimensional health-related data and bioresources collected from the cohort is anticipated to develop methods for evaluating functional status and elucidating multilevel, cross-scale interactions and regulatory mechanisms of healthy aging. The findings from this study will enhance the understanding of health changes due to aging, facilitate efficient and effective interventions to maintain functional ability, and reduce the incidence and severity of age-related diseases, thereby further promoting healthy aging.
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The direct antitumor effect of bevacizumab (BEV) has long been debated. Evidence of the direct antitumor activities of drugs are mainly obtained from in vitro experiments, which are greatly affected by experimental conditions. In this study, we evaluated the effect of BEV-containing medium renewal on the results of in vitro cytotoxicity experiments in A549 and U251 cancer cells. We observed starkly different results between the experiments with and without BEV-containing medium renewal. Specifically, BEV inhibited the tumor cell growth in the timely replacement with a BEV-containing medium but promoted tumor cell growth without medium renewal. Meanwhile, compared with the control, a significant basic fibroblast growth factor (bFGF) accumulation in the supernatant was observed in the group without medium renewal but none in that with replaced medium. Furthermore, bFGF neutralization partially reversed the pro-proliferative effect of BEV in the medium non-renewed group, while exogenous bFGF attenuated the tumor cell growth inhibition of BEV in the medium-renewed group. Our data explain the controversy over the direct antitumor effect of BEV in different studies from the perspective of the compensatory autocrine cytokines in tumor cells.
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Bevacizumab , Proliferación Celular , Factor 2 de Crecimiento de Fibroblastos , Humanos , Factor 2 de Crecimiento de Fibroblastos/farmacología , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Bevacizumab/farmacología , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Medios de Cultivo/química , Medios de Cultivo/farmacología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Inhibidores de la Angiogénesis/farmacología , Células A549 , Antineoplásicos Inmunológicos/farmacologíaRESUMEN
Background and aim: Symptomatic intracranial hemorrhage (sICH) was the most serious complication associated with alteplase intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) patients. However, the relationship between serum sodium levels and post-thrombolysis symptomatic intracranial hemorrhage has not been investigated. Therefore, the aim of this study was to investigate the relationship between pre-thrombolysis serum sodium levels and sICH after IVT, as well as to explore the optimal pre-thrombolysis serum sodium levels for lowering the risk of sICH following IVT. Methods: From July 1, 2017 to April 30, 2023, out-of-hospital AIS patients who received IVT in the emergency department were enrolled in this study. Serum sodium levels were measured at admission prior to IVT, and National Institutes of Health Stroke Scale scores were continuously assessed during and after thrombolysis. Routine follow-up neuroimaging was performed between 22 to 36 h after IVT. Initially, three logistic regression models and restricted cubic splines (RCS) were established to investigate the relationship between serum sodium levels and post-thrombolysis sICH. Furthermore, to evaluate the predictive value of serum sodium for post-thrombolysis sICH, we compared area under the receiver operating characteristic curve (AUROC) and net reclassification improvement (NRI) before and after incorporating serum sodium into traditional models. Finally, subgroup analysis was conducted to explore interactions between serum sodium levels and other variables. Results: A total of 784 AIS patients who underwent IVT were enrolled, among whom 47 (6.0%) experienced sICH. The median serum sodium concentration for all patients was 139.10 [interquartile ranges (IQR): 137.40-141.00] mmol/L. Patients who developed sICH had lower serum sodium levels than those without sICH [138.20(IQR:136.00-140.20) vs. 139.20(IQR:137.40-141.00), p = 0.031]. Logistic regression analysis (model 3) revealed a 14% reduction in the risk of post-thrombolysis sICH for every 1 mmol/L increase in serum sodium levels after adjusting for confounding variables (p < 0.001). The risk of post-thrombolysis sICH was minimized within the serum sodium range of 139.1-140.9 mmol/L compared to serum sodium concentration below 137.0 mmol/L [odds ratio (OR) = 0.33, 95% confidence interval (CI): 0.13-0.81] in model3. Furthermore, there was a significant trend of decreasing risk for sICH as serum sodium concentrations increased across the four quartiles (P for trend = 0.036). The RCS analysis indicated a statistically significant reduction in the risk of sICH as serum sodium levels increased when the concentration was below 139.1 mmol/L. Incorporating serum sodium into traditional models improved their predictive performance, resulting in higher AUROC and NRI values. Subgroup analysis suggested that early infarct signs (EIS) appeared to moderate the relationship between serum sodium and sICH (p < 0.05). Conclusion: Lower serum sodium levels were identified as independent risk factors for post-thrombolysis sICH. Maintaining pre-thrombolysis serum sodium concentrations above 139.1 mmol/L may help reduce the risk of post-thrombolysis sICH.
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The Al-Mn alloy heat exchanger fin production process includes a brazing treatment at s high temperature of 600 °C, in which coarse grains are preferred for their high resistance to deformation at elevated temperatures by decreasing the grain boundary sliding. In this study, Al-1.57Mn-1.57Zn-0.58Si-0.17Fe alloy foils cold rolled by 81.7% (1.1 mm in thickness) and 96.5% (0.21 mm in thickness) were annealed at 100-550 °C for 1 h to investigate their recrystallization behavior, grain sizes, and precipitates by increasing the annealing temperature, using micro-hardness measurement, electron back-scattered diffraction (EBSD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. The micro-hardness results showed that the recrystallization finishing temperatures for the two samples were almost the same, 323 ± 2 °C. The EBSD results showed that when the annealing temperature decreased from 550 to 400 °C, the recrystallized grain sizes of the two samples were nearly identical-both increased slightly. Further decreasing the annealing temperature from 400 to 330 °C caused the grain sizes to increase more, with the thinner foil sample having a more significant increase. The SEM and TEM observations showed that the micron-sized primary-phase remained unchanged during the annealing process. The nano-sized secondary phase precipitates formed during the hot-rolling process experienced a coarsening and dissolving process upon annealing. The particle size of the secondary phase increased from 32 nm to 44 nm and the area fraction decreased from 4.2% to 3.8%. The nucleation analysis confirmed that the large primary-phase could act as a nucleation site through particle stimulated nucleation (PSN) mode. The relatively dense secondary phase precipitates with small sizes at lower temperatures could provide higher Zener drag to the grain boundaries, leading to fewer nuclei and thereafter coarser grains. The coarsening of the recrystallized grains in the foils could be implemented through thickness reduction and/or precipitation processes to form densely distributed nano-sized precipitates.
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Background: Acute myocardial infarction is the myocardial necrosis caused by acute and persistent ischemia and hypoxia of coronary arteries. It can be complicated with arrhythmia, shock or heart failure, and often can endanger life. The disease is most common in Europe and the United States, where about 1.5 million heart attacks occur each year. China has shown a clear upward trend in recent years, with at least 500 000 new cases and at least 2 million new cases every year. Cardiac rehabilitation nursing is a kind of comprehensive nursing that aims to restore the body function of patients with myocardial infarction. Objective: To explore the therapeutic effect of cardiac rehabilitation nursing in patients with myocardial infarction. Design: This was a case-control retrospective study. Setting: This study was conducted in the Department of Heart Center, Shanghai Sixth People's Hospital. Participants: 86 patients with acute myocardial infarction admitted to the Heart Center of Shanghai Sixth People's Hospital from January 2019 to August 2022 were selected and randomly divided into observation and control groups, with 43 cases in each group. Patients aged from 40-79 years old and were confirmed to have acute myocardial infarction by examination and histopathological analysis. Interventions: The observation group was given cardiac rehabilitation nursing, including psychological nursing, rehabilitation training, cardiac rehabilitation training, diet and defecation care and health education, and the control group was assigned routine nursing. Primary Outcome measures: (1) anxiety and depression were assessed by Zung's self-rating anxiety scale and self-rating depression scale (2) cardiac function was assessed by left ventricular ejection fraction and left ventricular end-diastolic volume (3) 6-minute walk distance (4) incidence of complications (5) length of hospital stay (6) levels of inflammatory factors and N-terminal pro-brain natriuretic peptide concentration (7) incidence of arrhythmia. Results: After the intervention, there was still no significance in either group's left ventricular end-diastolic volume level [(72.24±8.47) vs (71.98±8.35)] (P = .473). However, the anxiety and depression scores [(42.10±5.17) and (44.01±4.53) vs (44.01±4.53) and (51.37±4.85)], complication rate (6.9% vs 16.2%), length of hospital stay [(18.66±7.03) vs (26.11±8.14)], inflammatory factor levels [(1.95±0.51) and (319.47±33.72) vs (2.71±0.45) and (451.07±39.54)], serum N-terminal pro-brain natriuretic peptide level [(2525.8±1236.5) vs (3064.4±859.0)], and incidence of arrhythmia (3 cases, 2 cases, 1 case and 1 case vs 5 cases, 6 cases, 8 cases and 7 vases) in the observation group were lower compared to the control group (P = .000, P = .002, P=0.023, P = .045, P = .032, P = .011, and P = .027). The left ventricular ejection fraction level and 6-minute walk distance of the observation group [(60.39±5.38) and (347.31±21.01) vs (54.97±6.24) and (320.24±21.71)] were better relative to the control group (P = .037 and P = .000). Conclusion: For patients with myocardial infarction, the implementation of cardiac rehabilitation nursing can effectively alleviate the anxiety and depression of patients, decrease the incidence of complications as well as inflammatory factors levels, and further shorten the hospital stay of patients, with high safety. Our study provides a clinical reference for patients with myocardial infarction w who need nursing care.
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Pyroptosis, an inflammatory caspase-dependent programmed cell death, plays a vital role in maintaining tissue homeostasis and activating inflammatory responses. Orthodontic tooth movement (OTM) is an aseptic force-induced inflammatory bone remodeling process mediated by the activation of periodontal ligament (PDL) progenitor cells. However, whether and how force induces PDL progenitor cell pyroptosis, thereby influencing OTM and alveolar bone remodeling remains unknown. In this study, we found that mechanical force induced the expression of pyroptosis-related markers in rat OTM and alveolar bone remodeling process. Blocking or enhancing pyroptosis level could suppress or promote OTM and alveolar bone remodeling respectively. Using Caspase-1-/- mice, we further demonstrated that the functional role of the force-induced pyroptosis in PDL progenitor cells depended on Caspase-1. Moreover, mechanical force could also induce pyroptosis in human ex-vivo force-treated PDL progenitor cells and in compressive force-loaded PDL progenitor cells in vitro, which influenced osteoclastogenesis. Mechanistically, transient receptor potential subfamily V member 4 signaling was involved in force-induced Caspase-1-dependent pyroptosis in PDL progenitor cells. Overall, this study suggested a novel mechanism contributing to the modulation of osteoclastogenesis and alveolar bone remodeling under mechanical stimuli, indicating a promising approach to accelerate OTM by targeting Caspase-1.
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Piroptosis , Técnicas de Movimiento Dental , Animales , Humanos , Ratones , Ratas , Remodelación Ósea/fisiología , Caspasa 1 , Ligamento PeriodontalRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Shou Tai Wan (STW), a traditional Chinese medicine formula, has been historically used for the treatment of recurrent spontaneous abortion (RSA). Despite its long-standing usage, the exact mechanism underlying the therapeutic effects of STW remains unclear in the existing literature. AIMS OF THIS STUDY: To explore the Pharmacological Mechanism of STW on RSA. METHODS: A network pharmacological methodology was utilized to predict the active compounds and potential targets of STW, collect the RSA targets and other human proteins of STW, and analyze the STW related networks. The animal experiments were also performed to validate the effect of STW on RSA. RESULTS: The results of network analysis showed that STW may regulate PI3K/AKT, MAPK, FoxO signaling pathways and so on. Animal experiment established the RSA model with CBA/J × DBA/2 mice. It was found that STW can reduce the embryo absorption rate of RSA group (p < 0.05) and balance the expression of Th 1/Th2 type cytokines compared with the model group. After 14 days of administration, the decidual and placental tissues were taken and the CD4+ T cells were isolated, and the phosphorylation level of signaling pathway was detected by Springbio720 antibody microarray. This experiment found that STW can significantly up-regulate the phosphorylation levels of STAT3 and STAT6 proteins in the STAT signaling pathway, and down-regulating the phosphorylation level of STAT1 protein. STW also significantly up-regulated the phosphorylation levels of Raf1, A-Raf, Ask1, Mek1, Mek2, JKK1, ERK1, ERK2, c-fos, c-Jun and CREB proteins in the MAPK signaling pathway, and down-regulate the phosphorylation levels of MEK6 and IKKb proteins. Compared with the RSA group, the STW group increased the expression levels of ERK1/2 mRNA and proteins and p-ERK1/2 proteins, and there was a statistical difference (p < 0.05). This is consistent with the chip results. CONCLUSION: STW may achieve therapeutic effects by interfering with the signaling pathways, biological processes and targets discovered in this study. It provides a new perspective for revealing the immunological mechanism of STW in the treatment of RSA, and also provides a theoretical basis for the clinical use of STW in the treatment of RSA.
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Aborto Habitual , Fosfatidilinositol 3-Quinasas , Ratones , Animales , Embarazo , Femenino , Humanos , Placenta , Ratones Endogámicos DBA , Ratones Endogámicos CBA , Aborto Habitual/tratamiento farmacológicoRESUMEN
Objective: This study aimed to create and validate a novel nomogram to predict the risk of symptomatic intracranial hemorrhage (sICH) in patients with acute ischemic stroke (AIS) who underwent intravenous thrombolysis (IVT). Methods: In this retrospective study, 784 patients with AIS who received IVT were enrolled. The patients were randomly divided into two groups: a training set (n=550, 70%) and a testing set (n=234, 30%). Utilizing multivariable logistic regression analysis, relevant factors for the predictive nomogram were selected. The performance of the nomogram was evaluated using various metrics, including the area under the receiver operating characteristic curve (AUC-ROC), the Hosmer-Lemeshow goodness-of-fit test, calibration plots, and decision curve analysis (DCA). Results: Multivariable logistic regression analysis showed that specific factors, including National Institutes of Health Stroke Scale (NIHSS) scores, Early infarct signs (EIS), and serum sodium, were identified as independent predictors of sICH. Subsequently, a nomogram was constructed using these predictors. The AUC-ROC values of the nomogram were 0.864 (95% CI: 0.810-0.919) and 0.831 (95% CI: 0.770-0.891) in the training and the validation sets, respectively. Both the calibration plots and the Hosmer-Lemeshow goodness-of-fit test showed favorable agreement in both the training and the validation sets. Additionally, the DCA indicated the practical clinical utility of the nomogram. Conclusion: The novel nomogram, which included NIHSS, EIS and serum sodium as variables, had the potential for predicting the risk of sICH in patients with AIS after IVT.
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Infected bone defects are a major challenge in orthopedic treatment. Native bone tissue possesses an endogenous electroactive interface that induces stem cell differentiation and inhibits bacterial adhesion and activity. However, traditional bone substitutes have difficulty in reconstructing the electrical environment of bone. In this study, we develop a self-promoted electroactive mineralized scaffold (sp-EMS) that generates weak currents via spontaneous electrochemical reactions to activate voltage-gated Ca2+ channels, enhance adenosine triphosphate-induced actin remodeling, and ultimately achieve osteogenic differentiation of mesenchymal stem cells by activating the BMP2/Smad5 pathway. Furthermore, we show that the electroactive interface provided by the sp-EMS inhibits bacterial adhesion and activity via electrochemical products and concomitantly generated reactive oxygen species. We find that the osteogenic and antibacterial dual functions of the sp-EMS depend on its self-promoting electrical stimulation. We demonstrate that in vivo, the sp-EMS achieves complete or nearly complete in situ infected bone healing, from a rat calvarial defect model with single bacterial infection, to a rabbit open alveolar bone defect model and a beagle dog vertical bone defect model with the complex oral bacterial microenvironment. This translational study demonstrates that the electroactive bone graft presents a promising therapeutic platform for complex defect repair.
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Osteogénesis , Andamios del Tejido , Ratas , Animales , Conejos , Perros , Biomimética , Regeneración Ósea , Diferenciación Celular , BacteriasRESUMEN
A novel Al-Mg-Si aluminum alloy with the addition of the micro-alloying element Er and Zr that was promptly quenched after extrusion has been studied. The solid solution and aging treatment of the novel alloy are studied by observing the microstructure, mechanical properties, and strengthening mechanism. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques are employed to examine the changes in the microstructure resulting from various solid solution treatments and aging treatments. The best strengthening effect can be achieved when the solubility of the MgSi phase and precipitate ßâ³ (Mg2Si phase) is at their maximum. The addition of Er and Zr elements promotes the precipitation of the ßâ³ phase and makes the bâ³ phase more finely dispersed. The aging strengthening of alloys is a comprehensive effect of the dislocation cutting mechanism and bypass mechanism, the joint effect of diffusion strengthening of Al3(Er,Zr) particles and the addition of Er and Zr elements promoting the precipitation strengthening of ßâ³ phases. In this paper, by adding Er and Zr elements and exploring the optimal heat treatment system, the yield strength of the alloy reaches 437 MPa and the tensile strength reaches 453 MPa after solid solution treatment at 565 °C/30 min and aging at 175 °C/10 h.
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Maintaining the stemness of bone marrow mesenchymal stem cells (BMMSCs) is crucial for bone homeostasis and regeneration. However, in vitro expansion and bone diseases impair BMMSC stemness, limiting its functionality in bone tissue engineering. Using a deep learning-based efficacy prediction system and bone tissue sequencing, we identify a natural small-molecule compound, dihydroartemisinin (DHA), that maintains BMMSC stemness and enhances bone regeneration. During long-term in vitro expansion, DHA preserves BMMSC stemness characteristics, including its self-renewal ability and unbiased differentiation. In an osteoporosis mouse model, oral administration of DHA restores the femur trabecular structure, bone density, and BMMSC stemness in situ. Mechanistically, DHA maintains BMMSC stemness by promoting histone 3 lysine 9 acetylation via GCN5 activation both in vivo and in vitro. Furthermore, the bone-targeted delivery of DHA by mesoporous silica nanoparticles improves its therapeutic efficacy in osteoporosis. Collectively, DHA could be a promising therapeutic agent for treating osteoporosis by maintaining BMMSC stemness.
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Adult tendon stem/progenitor cells (TSPCs) are essential for tendon maintenance, regeneration, and repair, yet they become susceptible to senescence with age, impairing the self-healing capacity of tendons. In this study, we employ a recently developed deep-learning-based efficacy prediction system to screen potential stemness-promoting and senescence-inhibiting drugs from natural products using the transcriptional signatures of stemness. The top-ranked candidate, prim-O-glucosylcimifugin (POG), a saposhnikovia root extract, could ameliorate TPSC senescent phenotypes caused by long-term passage and natural aging in rats and humans, as well as restore the self-renewal and proliferative capacities and tenogenic potential of aged TSPCs. In vivo, the systematic administration of POG or the local delivery of POG nanoparticles functionally rescued endogenous tendon regeneration and repair in aged rats to levels similar to those of normal animals. Mechanistically, POG protects TSPCs against functional impairment during both passage-induced and natural aging by simultaneously suppressing nuclear factor-κB and decreasing mTOR signaling with the induction of autophagy. Thus, the strategy of pharmacological intervention with the deep learning-predicted compound POG could rejuvenate aged TSPCs and improve the regenerative capacity of aged tendons.
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Envejecimiento , Tendones , Humanos , Adulto , Ratas , Animales , Diferenciación Celular , Células Madre , RegeneraciónRESUMEN
Macrophages are involved mainly in the balance between inflammation and tenogenesis during the healing process of tendinopathy. However, etiological therapeutic strategies to efficiently treat tendinopathy by modulating macrophage state are still lacking. In this study, we find that a small molecule compound Parishin-A (PA) isolated from Gastrodia elata could promote anti-inflammatory M2 macrophage polarization by inhibiting gene transcription and protein phosphorylation of signal transducers and activators of transcription 1. Local injection or sustained delivery of PA by mesoporous silica nanoparticles (MSNs) could almost recover the native tendon's dense parallel-aligned collagen matrix in collagenase-induced tendinopathy by modulating macrophage-mediated immune microenvironment and preventing heterotopic ossification. Especially, MSNs decrease doses of PA, frequency of injection and yield preferable therapeutic effects. Mechanistically, intervention with PA could indirectly inhibit activation of mammalian target of rapamycin to repress chondrogenic and osteogenic differentiation of tendon stem/progenitor cells by influencing macrophage inflammatory cytokine secretion. Together, pharmacological intervention with a natural small-molecule compound to modulate macrophage status appears to be a promising strategy for tendinopathy treatment.
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Aging impairs tendon stem/progenitor cell function and tendon homeostasis, however, effective treatments for aging-induced tendon diseases are lacking. Exosomes are naturally derived nanoparticles that contain bioactive molecules, and therefore, have attracted great interest in tissue engineering and regenerative medicine. In this study, it is shown that young exosomes secreted by stem cells from human exfoliated deciduous teeth (SHED-Exos) possess abundant anti-aging signals. These young bio-nanoparticles can alleviate the aging phenotypes of aged tendon stem/progenitor cells (AT-SCs) and maintain their tenogenic capacity. Mechanistically, SHED-Exos modulate histone methylation and inhibit nuclear factor-κB to reverse AT-SC aging. In a naturally aging mouse model, systemic administration of SHED-Exo bio-nanoparticles retards tendon degeneration. Interestingly, local delivery of SHED-Exos-loaded microspheres confers anti-aging phenotypes, including reduced senescent cells and decreased ectopic bone formation, thereby functionally and structurally rescuing endogenous tendon regeneration and repair capacity in aged rats. Overall, SHED-Exos, as natural bioactive nanoparticles, have promising translational and therapeutic potential for aging-related diseases.
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Exosomas , Animales , Ratones , Ratas , Humanos , Modelos Animales de Enfermedad , Células Madre/metabolismo , Células Madre/fisiología , Senescencia CelularRESUMEN
Background: Scarless endoscopic thyroidectomy (ET) is increasingly accepted by the growing amount of surgeons. The target of this study is to assess the efficacy and summarise the experiences of total areola approach for ET (TAAET). Subjects and Methods: TAAET was performed on 529 patients between January 2016 and October 2021. All operated patients were divided into two groups according to the chronological order. Demographic data, perioperative data and post-operative complications were collected to assess the effectiveness of TAAET. Results: Five hundred and twenty-eight patients were successfully treated with TAAET, while 1 case was converted to open surgery due to bleeding. The surgical approach consists of lobectomy or total thyroidectomy with or without central lymph node dissection. The post-operative pathology of 433 (81.9%) patients was diagnosed with T1 ~2N0M0. The average number of unilateral lymph node dissection was 7.72 ± 2.44 while the bilateral lymph node was 10.70 ± 3.72. In terms of complications, 38 cases had transient hoarseness, 28 cases had tetany and numbness, 3 cases had post-operative bleeding, 1 case had infection and 33 cases had subcutaneous fluid. There were statistically significant differences between the two groups with respect to transient hoarseness (P < 0.001), tetany and numbness (P = 0.005), intraoperative blood loss (P = 0.003) and operation time for malignant tumour (P < 0.001) because of the accumulation of surgical experience and the maturation of technology. Conclusions: TAAET which conforms to the anatomical pathway of open thyroidectomy is a safe, effective and feasible technique and is highly suitable for novices.
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The hot compression experiment of homogenized Al-5.2Mg-0.6Mn-0.29Zn-0.16Er-0.12Zr alloy was carried out by the Gleeble-3500 thermal simulation testing system. The deformation behavior in temperatures of 350~500 â and deformation rates of 0.01~10 s-1 was studied. The relationship between stress and strain rate and deformation temperature was analyzed. The constitutive equation of alloy high-temperature deformation was constructed by the Zener-Hollomon method, and the hot working diagram with the true strain of 0.2 and 0.5 was constructed according to the dynamic material model. The research results show that flow stress has a positive correlation with strain rate and a negative correlation with temperature. The steady flow stress during deformation can be described by a hyperbolic sinusoidal constitutive equation. Adding Er and Zr into Al-Mg alloy can not only refine grains and strengthen precipitation but also form a core-shell Al3(Er, Zr) phase. In the deformation process, Al3(Er, Zr) precipitates can pin dislocations and inhibit dynamic recrystallization (DRX). Dynamic recovery (DRV) is dominant during hot deformation. The mechanism of dynamic recovery is dislocation motion. At high temperatures, Al3(Er, Zr) can also inhibit grain coarsening. The average hot deformation activation energy of the alloy is 203.7 kJ/mol. This high activation energy can be due to the pinning effect of Er and Zr precipitates. The processing map of the alloy was analyzed and combined with the observation of microstructure, the hot deformation instability zone of the alloy was determined, and the suitable process parameters for hot deformation were obtained, which were 450~480 °C, and the strain rate is 0.01~0.09 s-1.
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BACKGROUND: In the context of climate change, it has been well observed that short-term temperature variability (TV) could increase the overall and cause-specific mortality and morbidity. However, the association between long-term TV and a broader spectrum of diseases is not yet well understood, especially in the elderly. METHODS: Our study used data from the fourth Urban and Rural Elderly Population (UREP) study. Long-term TV was calculated from the standard deviation (SD) of daily minimum and maximum temperatures within the study periods (2010-2014, 2011-2014, 2012-2014, 2013-2014, and 2014). Ten self-reported diseases and conditions were collected by questionnaire, including cataract, hypertension, diabetes, cardio-cerebrovascular diseases, stomach diseases, arthritis, chronic lung disease, asthma, cancer, and reproductive diseases. The province-stratified logistic regression model was used to quantify the association between long-term TV and the prevalence of each disease. RESULTS: A total of 184,047 participants were included in our study. In general, there were significant associations between TV and the prevalence of most diseases at the national level. Cardio-cerebrovascular disease (OR: 1.16, 95% CI: 1.13, 1.20) generated the highest estimates, followed by stomach diseases (OR: 1.15, 95% CI: 1.10, 1.19), asthma (OR: 1.14, 95% CI: 1.06, 1.22), chronic lung diseases (OR: 1.08, 95% CI: 1.03, 1.13), arthritis (OR: 1.08, 95% CI: 1.05, 1.11), and cataract (OR: 1.06, 95% CI: 1.02, 1.10). Moreover, the associations varied by geographical regions and across subgroups stratified by sex, household income, physical activity, and education. CONCLUSIONS: Our study showed that long-term exposure to TV was associated with the prevalence of main diseases in the elderly. More attention should be paid to the elderly and targeted strategies should be implemented, such as an early warning system.
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Asma , Exposición a Riesgos Ambientales , Humanos , Anciano , Temperatura , Estudios Transversales , Exposición a Riesgos Ambientales/análisis , China/epidemiología , Asma/epidemiologíaRESUMEN
Endometriosis (EMS) is a challenging gynecological disorder prevalent in reproductive-aged women, and Th1/Th2 cytokines are implicated in EMS progression. This study probed the serum levels and clinical values of Th1/Th2 cytokines in EMS patients. Firstly, the clinic characteristics of EMS and control patients were recorded. The levels of interferon (IFN)-γ, interleukin (IL)-2, IL-4, and IL-10 in the serum of EMS and control patients were identified, respectively. The correlations between Th1 and Th2 cytokines and the diagnostic values of these cytokines in EMS were analyzed. We observed that EMS patients had obvious differences from the controls in dysmenorrhea, dyspareunia, pelvic pain, nulliparous, and CA125 levels. Serum IFN-γ and IL-2 were lower while IL-4 and IL-10 were higher in EMS patients. Serum IFN-γ, IL-4 were negatively correlated with serum IL-2, and IL-10 in EMS patients. Th1/Th2 cytokines may help the diagnosis of EMS. Serum IFN-γ and IL-2 were independent protective factors for EMS while dysmenorrhea, dyspareunia, nulliparous, and serum IL-4 and IL-10 were independent risk factors for EMS. Collectively, serum Th1/Th2 cytokine levels helped the diagnosis of EMS, with IFN-γ and IL-2 serving as independent protective factors whilst IL-4 and IL-10 serving as independent risk factors.
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Dispareunia , Endometriosis , Humanos , Femenino , Adulto , Citocinas , Interleucina-10 , Interleucina-2 , Interleucina-4 , Relevancia Clínica , Dismenorrea , Células TH1 , Células Th2RESUMEN
OBJECTIVES: This study aimed to reveal the epidemic characteristics of chronic diseases among the Chinese older population and provide empirical strategies for the prevention and management of chronic diseases in the seniors in China. DESIGN: A national cross-sectional study. SETTING AND PARTICIPANTS: A total of 224,640 Chinese residents aged 60 and older were invited, and 222,179 (98.9%) participated in our survey. METHODS: Standardized questionnaires were used to collect socioeconomic information and self-reported physician-diagnosed chronic diseases. The associations between individual socioeconomic status and chronic diseases were estimated using generalized linear mixed-effects models. RESULTS: The national prevalence of any chronic diseases was 81.1% (95% CI 80.9-81.2), representing 179.9 million Chinese older adults. The prevalence increased with aging and peaked at 80 to 84 years old (87.2, 95% CI 86.7-87.7), this is consistent with studies in developing countries. Women (84.2, 84.0-84.4), rural residents (82.6, 82.4-82.8), and ethnic minorities (82.2, 81.5-82.8) had a higher prevalence than men (77.7, 77.4-77.9), urban residents (79.7, 79.5-79.9), and people of Han ethnicity (81.0, 80.8-81.2), respectively. For provincial prevalence, Tibet had the highest prevalence of chronic diseases (91.8, 91.5-92.0), and Fujian had the lowest (72.7, 72.5-72.9). The absolute differences between the highest and lowest provinces for the specific chronic condition ranged from 2.78% for cancer to 36.3% for cardiovascular diseases. CONCLUSIONS AND IMPLICATIONS: Chronic diseases were highly prevalent among older adults in China and varied geographically. Advanced socioeconomic status appeared to have double-edged impacts on the prevalence of chronic diseases. Our findings support that reducing gender and geographic disparities should be prioritized in China's chronic disease prevention and management, and an affordable long-term care services system for older adults should be established urgently in China.
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Clase Social , Masculino , Humanos , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Estudios Transversales , Factores Socioeconómicos , China/epidemiología , Enfermedad Crónica , PrevalenciaRESUMEN
A novel Al-Cu-Zr alloy is designed in this paper, which provides a method for further improving the strength of Al-Cu alloys. In this paper, the addition of the micro-alloying element Zr in Al-Cu alloy was studied. The effect of aging treatment on the mechanical properties and precipitation behavior of the alloy was studied. With the addition of Zr, Al3Zr phases were formed in the alloy, which acts as obstacles to dislocation motion. In addition, Al3Zr phases can be used as the nucleation site of θ' phases to promote precipitation. All this can improve the strength of Al-Cu alloys. After one-step aging, corresponding to the highest hardness, the largest amount of θ' phases were observed in the alloy matrix. By contrast, after two-step aging, the θ' phases were finer, and a large amount of Guinier-Preston (GP) zones formed during the pre-aging step, which were transformed into denser and finer θ' phases in the secondary aging step. After the same solution treatment (540 °C/12 h), undergoing 120 °C/4 h + 175 °C/10 h two-step aging, the ultimate tensile strength, yield strength, and elongation of the Al-Cu-Zr alloy were 398.7 MPa, 313.3 MPa, and 7.9%, respectively.