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Cervical human papillomavirus (HPV) infection is believed to increase the risks of pregnancy failure and abortion, however, whether the uterine cavity HPV infection reduces pregnancy rate or increases miscarriage rate remains unclarified in infertile women undergoing assisted reproductive technology (ART) treatment. Therefore, we aimed to assess ART outcomes in the presence of intrauterine HPV. This was a hospital-based multicenter (five reproductive medicine centers) matched cohort study. This study involved 4153 infertile women undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection treatment in five reproductive medicine centers between October 2018 and 2020. The spent embryo transfer media sample with endometrium tissue were collected and performed with flow-through hybridization and gene chips to detect HPV DNA. According to basic characteristics, HPV-positive and negative patients were matched in a ratio of 1:4 by age, body mass index transfer timing, transfer type, and number of embryos transferred. The primary outcome was pregnancy and clinical miscarriage rates in the transfer cycle underwent HPV detection. 92 HPV-positive and 368 HPV-negative patients were screened and analyzed statistically. Univariate analysis showed uterine cavity HPV infection resulted in lower rates of ongoing pregnancy (31.5% vs. 44.6%; p = 0.023), implantation (32.3% vs. 43.1%; p = 0.026), biochemical pregnancy (47.8% vs. 62.5%; p = 0.010), and clinical pregnancy (40.2% vs. 54.3%; p = 0.015) compared with HPV negative group. The infertile female with positive HPV also had a slightly higher frequency of biochemical miscarriage (15.9% vs. 13.0%; p = 0.610) and clinical miscarriage (24.3% vs. 15.5%; p = 0.188). These findings suggest that HPV infection in the uterine cavity is a high risk for ART failure. HPV screening is recommended before ART treatment, which may be benefit to improving pregnancy outcome.
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Aborto Espontâneo , Infertilidade Feminina , Infecções por Papillomavirus , Gravidez , Humanos , Masculino , Feminino , Infecções por Papillomavirus/diagnóstico , Infertilidade Feminina/terapia , Papillomavirus Humano , Estudos de Coortes , Sêmen , Transferência Embrionária/métodos , Técnicas de Reprodução Assistida , Fertilização in vitro , Falha de TratamentoRESUMO
BACKGROUND: This study aimed to identify potential symptom clusters among primary brain tumor patients using factor analysis. Understanding these clusters enables better-targeted interventions post-craniotomy. METHODS: A total of 211 participants visiting Department of Neurosurgery at Shanghai Tenth People's Hospital for proposed surgical treatment between January 2021 and March 2022 were enrolled. Two weeks after craniotomy, the patients' symptoms were measured using MDASI-BT (M.D. Anderson Symptom Inventory Brain Tumor Module), and factor analysis was performed to identify symptom clusters. RESULTS: A total of three symptom clusters, i.e., symptom cluster 1, symptom cluster 2, and symptom cluster 3, were identified. Among them, symptom cluster 1 represented the fatigue-related symptom cluster, including fatigue, lethargy, dry mouth, pain, and sleep disturbance (Cronbach's α = 0.742); symptom cluster 2 represented the gut-brain axis symptom cluster, including loss of appetite, weakness in one side of the body, and change in bowel habits (Cronbach's α = 0.532); and symptom cluster 3 represented the self-image symptom cluster, including change in appearance, sadness, and distress (Cronbach's α = 0.547). CONCLUSION: This study identified three potential symptom clusters among primary brain tumor patients. Understanding these clusters could well contribute to earlier interventions and improved quality of care.
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Neoplasias Encefálicas , Craniotomia , Humanos , Neoplasias Encefálicas/cirurgia , Masculino , Feminino , Pessoa de Meia-Idade , Craniotomia/efeitos adversos , Craniotomia/métodos , Adulto , Idoso , China , Análise Fatorial , Inquéritos e Questionários , Fadiga/etiologiaRESUMO
Entry retaining via roof cutting is a new longwall mining method that has emerged in recent years, and is characterized by high resource utilization and environmental friendliness. Due to the complexity of this method, a field study is commonly employed for process optimization. Roof blasting is a key operation for retaining the entry, and the current practice involves dynamically adjusting blasting parameters through on-site testing and postblasting monitoring. However, the existing literature lacks detailed descriptions of blasting operations, making it difficult for field engineers to replicate the results. In this study, based on a roof cutting project for entry retaining, a preliminary design of blasting parameters is made based on theories and on-site geological conditions. The on-site test methods and equipment for roof-cutting blasting are described in detail, and the fractural patterns under different blasting parameters are analyzed. After the retreat of the working face, the state of roof caving in the goaf is analyzed based on monitoring data, and the effectiveness of top cutting is evaluated through reverse analysis, leading to dynamic adjustments of the blasting parameters. This research provides a reproducible construction method for roof-cutting operations and establishes the relationship between blasting parameters and post-mining monitoring data. It contributes to the development of fundamental theories and systematic technical systems for entry retaining via roof cutting, offering high-quality case studies for similar geological engineering projects.
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The longwall mining method with gob-side entry retaining via roof cutting is a new underground coal mining method which has the characteristics of a high resource recovery ratio and environmental friendliness. Due to the complexity of this method, the research method of case-based dynamic on-site monitoring, analysis, adjustment, and optimization is usually adopted. Based on a roadway retaining via roof cutting project, in addition to the traditional indirect monitoring method of hydraulic support pressure, this study innovatively establishes a direct monitoring method for roof caving by monitoring the gangue pressure in the goaf, which provides data for the roof cutting effect and offers a new method for studying the overlying strata movement. In the project, a comprehensive monitoring and analysis system was established, including gangue pressure, cable bolt stress, bracket pressure, roadway deformation, and roof separation, which was used to dynamically analyze the effect of roof cutting and optimize the support design. The results show that the pressure of the hydraulic support close to the roof cutting is low, indicating that roof cutting is favorable in the roadway retaining mining method. The roadway deformation in the advanced abutment pressure area of the working face is small. The mining-induced stress caused by the collapse and compaction of the overlying strata in the goaf is the dominant factor affecting the effect of roadway retaining, especially in the 50-100 m range behind the working face, where the dynamic load causes high bearing capacity of the support elements, large roadway convergence, and roof separation. Temporary support and supplementary reinforcement should be added when necessary. The monitoring system presented in this study is highly comprehensive, simple, reliable, and low in cost, providing a reference for roof cutting roadway retaining projects and roof caving-related studies.
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BACKGROUND: Gastric cancer is one of the leading cancer-related death causes. Enormous efforts have been focused on this field in these years. However, clinical trial failure is becoming a massive obstacle for researchers to apply their research results for clinical use. This study aimed to analyze the reasons behind clinical failures and identify potential risk factors of clinical trial failures. METHODS: On December, 1, 2021, we queried ClinicalTrials.gov for gastric cancer listed in phase II/III. We included trials specifying their interests in "stomach cancer", "Stomach Neoplasms", "Gastric Cancer", "Gastric Neoplasms", "Gastric Carcinoma", "Stomach Carcinoma", "Gastroesophageal Junction Cancer". Exclude criteria are: (1) Trials that start prior to 01/01/2007 and start after 12/01/2020; (2) Trials with "not yet recruiting", "suspended", "withdrawn", or "unknown" status; (3) Trials do not provide an anticipated accrual number or a start date. RESULTS: A total of 567 trials are included. 10.2% of these trials are failed. 16 (2.82%) were terminated for good reasons, and 42 (7.41%) were terminated for bad reasons. Multi-centre (P-value = 0.088) and anticipated accrual (P-value = 0.099) are potential risk factors for clinical failures in the simple logistic regression model. After considering the interaction between multi-centre and anticipated accrual, the odds ratio of anticipated accrual is 0.60 (P-value = 0.009) in single centre trials. In multi-centre trials, the odds ratio of anticipated accrual is 0.72 (P-value = 0.025). The primary reason for gastric cancer trial terminations is recruitment failure. CONCLUSION: The rate that trials terminated in gastric cancer has decreased compared to previous studies. Comparing to other types of oncology trials, poor accrual continues to be the predominant reason, followed by business or sponsor reasons. Single-center trials with smaller anticipated accrual number are more likely to be terminated which may resulted by limited resources invested to the trial. Single-center design exacerbated the difficulty of participant recruitment. Future studies need to continue tracking the rate of trial termination across oncology and whether the reasons behind them have changed.
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Carcinoma , Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Fatores de Risco , Neoplasias Gástricas/terapia , Junção EsofagogástricaRESUMO
In practical assembly enterprises, customization and rush orders lead to an uncertain demand environment. This situation requires managers and researchers to configure an assembly line that increases production efficiency and robustness. Hence, this work addresses cost-oriented mixed-model multimanned assembly line balancing under uncertain demand, and presents a new robust mixed-integer linear programming model to minimize the production and penalty costs simultaneously. In addition, a reinforcement learning-based multiobjective evolutionary algorithm (MOEA) is designed to tackle the problem. The algorithm includes a priority-based solution representation and a new task-worker-sequence decoding that considers robustness processing and idle time reductions. Five crossover and three mutation operators are proposed. The Q -learning-based strategy determines the crossover and mutation operator at each iteration to effectively obtain Pareto sets of solutions. Finally, a time-based probability-adaptive strategy is designed to effectively coordinate the crossover and mutation operators. The experimental study, based on 269 benchmark instances, demonstrates that the proposal outperforms 11 competitive MOEAs and a previous single-objective approach to the problem. The managerial insights from the results as well as the limitations of the algorithm are also highlighted.
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Androgenetic alopecia (AGA) is a common type of hair loss in men and efficacy and safety of current medical treatment remain limited. Therefore, the present study aimed to investigate the efficacy and safety of botulinum toxin type A (BTA) combined with Minoxidil in patients with AGA. 60 male patients were included in this study and control group received topical 5% Minoxidil and the treatment group received BTA combined with topical 5% Minoxidil. BTA injections (60-70 U) were administered at 30-35 scalp sites. Head photographs were taken at baseline, 2nd, 4th, and 6th months. Clinical descriptions recorded scalp conditions, and patient satisfaction along with Dermatology Life Quality Index scores were documented. The treatment group (TG) showed significant hair growth differences compared to the control group (CG) at the 4th month (P < 0.001) and 6th month (P = 0.0046) post-treatment. TG had improved Investigator Global Assessment (IGA) scores in the 4th month (P = 0.0001) and 6th month (P = 0.0259) compared to CG. Patient satisfaction in TG for hair growth and scalp improvement was higher than CG (all P < 0.05). TG exhibited substantial quality of life improvement at the 4-month (P = 0.0009) and 6-month (P = 0.0099). No adverse reactions were observed post-botulinum toxin injection. BTA combined with Minoxidil effectively promotes hair growth, enhances the quality of life, and alleviates scalp symptoms in male AGA patients at 4th and 6th months, with no adverse effects compared to Minoxidil alone.Trial registration number: Ethics Committee of Shanghai Tongji Hospital (ID: K-2018-026).
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Alopecia , Toxinas Botulínicas Tipo A , Minoxidil , Satisfação do Paciente , Qualidade de Vida , Humanos , Masculino , Minoxidil/administração & dosagem , Minoxidil/efeitos adversos , Alopecia/tratamento farmacológico , Toxinas Botulínicas Tipo A/administração & dosagem , Toxinas Botulínicas Tipo A/efeitos adversos , Adulto , Resultado do Tratamento , Pessoa de Meia-Idade , Administração Tópica , Quimioterapia Combinada/métodos , Cabelo/crescimento & desenvolvimento , Cabelo/efeitos dos fármacos , Couro Cabeludo , Adulto JovemRESUMO
BACKGROUND: This study aimed to evaluate the characteristics of bone metabolism and fracture risk in the type 2 diabetes mellitus (T2DM) patients with distal symmetric polyneuropathy (DSPN). METHODS: A total of 198 T2DM individuals were recruited from January 2017 to December 2020. Patients with DSPN were evaluated by strict clinical and sensory thresholds. Biochemical parameters and bone mineral density (BMD) were measured. The BMD, bone turnover markers, and probability of fracture were compared between two groups, and the factors related to BMD and probability of hip fracture in 10 years were further explored. RESULTS: Compared with type 2 diabetes mellitus without distal symmetric polyneuropathy (T2DN-) patients, type 2 diabetes mellitus with distal symmetric polyneuropathy (T2DN+) patients had lower level of cross-linked C-telopeptide (CTX) (0.32 ± 0.19 vs 0.38 ± 0.21 ng/mL, p = 0.038) and higher level of bone-specific alkaline phosphatase (BALP) (15.28 ± 5.56 vs 12.58 ± 4.41 µg/mL, p = 0.003). T2DN+ patients had higher BMD of lumbar L1-L4 (1.05 ± 0.19 vs 0.95 ± 0.37, p = 0.027) and higher probability of hip fracture (0.98 ± 0.88 vs 0.68 ± 0.63, p = 0.009) as compared to T2DN- individuals. Univariate correlation analysis showed that BALP level (coefficient (coef) = -0.054, p = 0.038), CTX level (coef = -2.28, p = 0.001), and hip fracture risk (coef = -1.02, p < 0.001) were negatively related to the BMD of L1-L4. As for the risk of hip fracture evaluated by WHO Fracture Risk Assessment Tool (FRAX), age (coef = 0.035, p < 0.001), use of insulin (coef = 0.31, p =0.015), and levels of BALP (coef = 0.031, p = 0.017) and CTX (coef = 0.7, p = 0.047) were positively related to the risk of hip fracture. Multivariate regression analysis showed that CTX level (coef = -1.41, p = 0.043) was still negatively related to BMD at the lumbar spine. CONCLUSION: This study indicates that T2DM patients with DSPN have special bone metabolism represented by higher BALP level and lower CTX level which may increase BMD at the lumbar spine.
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Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Fraturas do Quadril , Polineuropatias , Humanos , Masculino , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Neuropatias Diabéticas/etiologia , Densidade Óssea , Fraturas do Quadril/etiologia , Biomarcadores , Remodelação ÓsseaRESUMO
Based on the disaster characteristics and the geo-conditions at the scene, in this study, the occurrence mechanism of a serious rock burst accident that occurred in the Tangshan Coal Mine, China, was analysed. Ground stress measurements showed that the mine is in a high ground stress area dominated by horizontal tectonic stress around 33 MPa. Laboratory testing revealed that the coal was a hard seam of 8.3 MPa over bedded by a thick and hard roof stratum with uniaxial compressive strength of 66 MPa. The calculation results indicated that the accident occurred in the roof rebounding area. It is proposed that the hard roof and the hard coal seam formed a seesaw structure around the working face. The vertical pressure relief caused the rib coal mass to lose its clamping forces from the roof and floor and rush into the roadway, resulting in a rock burst accident. Based on the causality mechanism of the rock burst disaster developed in this study, pertinent coal bump prevention measures have been undertaken in practice. Large-diameter boreholes were drilled to eliminate the pivot effect of the seam. Roof blasting was undertaken to prevent the roof from forming a seesaw plank. To summarize, a new causality mechanism for rock burst in coal mines under hard roof and hard seam geo-conditions was developed.
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Coal contains cracks and has strong heterogeneity, so the data dispersion is large in laboratory tests. In this study, 3D printing technology is used to simulate hard rock and coal, and the rock mechanics test method is used to carry out the coal-rock combination experiment. The deformation characteristics and failure modes of the combination are analyzed and compared with the relevant parameters of the single body. The results show that the uniaxial compressive strength of the composite sample is inversely proportional to the thickness of the weak body and directly proportional to the thickness of the strong body. The Protodyakonov model or ASTM model can be used as a verification method for the results of a uniaxial compressive strength test of coal-rock combination. The elastic modulus of the combination is the equivalent elastic modulus, and the elastic modulus of the combination is between the elastic modulus of the two constituent monomers, which can be analyzed using the Reuss model. The failure of the composite sample occurs in the low-strength material, while the high-strength section is rebounding as an extra load on the low-strength body, which may cause a sharp increase in the strain rate of the weak body. The main failure mode of the sample with a small height-diameter ratio is splitting, and the failure mode of the sample with a large height-diameter ratio is shear fracturing. When the height-diameter ratio is not greater than 1, it shows pure splitting, and when the height-diameter ratio is 1~2, it shows a mixed mode of splitting and shear fracture. The shape has a significant effect on the uniaxial compressive strength of the composite specimen. For the impact propensity, it can be determined that the uniaxial compressive strength of the combination is higher than that of the single body, and the dynamic failure time is lower than that of the single body. It can hardly determine the elastic energy and the impact energy of the composite with the relationship to the weak body. The proposed methodology provides new cutting-edge test technologies in the study of coal and coal-like materials, with an exploration of their mechanical properties under compression.
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Purpose: The objective of this study was to employ machine learning (ML) models utilizing non-invasive factors to achieve early and low-cost identification of MetS in a large physical examination population. Patients and Methods: The study enrolled 9171 participants who underwent physical examinations at Northern Jiangsu People's Hospital in 2009 and 2019, to determine MetS based on criteria established by the Chinese Diabetes Society. Non-invasive characteristics such as gender, age, body mass index (BMI), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were collected and used as input variables to train and evaluate ML models for MetS identification. Several ML models were used for MetS identification, including logistic regression (LR), k-nearest neighbors algorithm (k-NN), naive bayesian (NB), decision tree (DT), random forest (RF), artificial neural network (ANN), and support vector machine (SVM). Results: Our ML models all showed good performance in the 10-fold cross-validation except for the SVM model. In the external validation, the NB model exhibited the best performance with an AUC of 0.976, accuracy of 0.923, sensitivity of 98.32%, and specificity of 91.32%. Conclusion: This study proposed a new non-invasive method for early and low-cost identification of MetS by using ML models. This approach has the potential to serve as a highly sensitive, convenient, and cost-effective tool for large-scale MetS screening.
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Introduction: In the elder population, both low hemoglobin (Hb)/anemia and osteoporosis (OP) are highly prevalent. However, the relationship between Hb and OP is still poorly understood. This study was to evaluate the correlation between Hb and OP in Chinese elderly population. Methods: One thousand and sisty-eight individuals aged 55-85 years were enrolled into this cross-sectional study during June 2019-November 2019. Data on the demographics and clinical characteristics were recorded. Detections of complete blood count, liver/kidney function, glucose metabolism and lipid profile, and thoracolumbar X-ray were performed, and bone mineral density (BMD) at lumbar spine 1-4, femur neck, and total hip was measured by dual-energy X-ray absorptiometry (DXA). Univariate and multivariate linear regression analyses were employed to evaluate the correlation between Hb with BMD T-score. Logistic regression analysis was performed to access the correlation between different Hb levels and the odds ratio (OR) for OP. Results: Compared with non-OP group, OP patients had lower level of Hb. Univariate linear regression analysis indicated Hb level was positively related to the BMD of lumbar spine 1-4, femur neck and total hip, and this relationship remained after adjusting confounding variables [gender, age, body mass index (BMI), diabetes mellitus (DM) and morphological vertebral fracture]. Logistic regression analysis showed the ORs for OP decreased with the increase of Hb. Compared with the subjects with the lowest quartile of Hb, the OR for OP in the highest quartile group was 0.60 (0.41-0.89) after adjusting for gender, age and BMI, and the OR for OP was 0.62 (0.41-0.92) after further adjustment for gender, age, BMI, DM, and lipid indexes. Discussion: In conclusion, Lower Hb level is related to lower BMD in the elderly population. However, whether Hb level could be used to predict the risk of OP needs to be further determined in more longitudinal clinical studies.
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População do Leste Asiático , Osteoporose , Idoso , Humanos , Densidade Óssea , Estudos Transversais , Hemoglobinas , Lipídeos , Vértebras Lombares , Osteoporose/epidemiologia , Pessoa de Meia-Idade , Idoso de 80 Anos ou maisRESUMO
Adipose-derived stem cells (ADSCs) have important applications in basic research, especially in fat transplantation. Some studies have found that three-dimensional (3D) spheroids formed by mesenchymal stem cells have enhanced therapeutic potential. However, the fundamental basics of this effect are still being discussed. ADSCs were harvested from subcutaneous adipose tissues and 3D spheroids were formed by the automatic aggregation of ADSCs in a non-adhesive 6-well plate. Oxygen glucose deprivation (OGD) was used to simulate the transplantation microenvironment. We found that 3D culture of ADSCs triggered cell autophagy. After inhibiting autophagy by Chloroquine, the rates of apoptosis were increased. When the 3D ADSC-spheroids were re-planked, the number of senescent ADSCs decreased, and the proliferation ability was promoted. In addition, there were more cytokines secreted by 3D ADSC-spheroids including VEGF, IGF-1, and TGF-ß. After adding the conditioned medium with human umbilical vein endothelial cells (HUVECs), 3D ADSC-spheroids were more likely to promote migration, and tube formation, stimulating the formation of new blood vessels. Fat grafting experiments in nude mice also showed that 3D ADSC-spheroids enhanced survival and neovascularization of fat grafts. These results suggested that 3D spheroids culturing of ADSCs can increase the therapeutic potential in fat transplantation.
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Purpose: Metabolic syndrome (MetS) is a rising global concern with an increasing prevalence. This study aimed to evaluate the relationship between serum uric acid to creatinine ratio (SUA/Cr) and MetS in adults with overweight/obesity in China. Patients and Methods: We conducted a cross-sectional study comprising 4699 participants with overweight/obesity who underwent physical examinations. Their serum levels of various components, including total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), fasting plasma glucose (FPG), creatinine (Cr), and uric acid (UA) were measured. Renal function-normalized SUA was calculated using SUA/Cr. Logistic regression analysis was employed to investigate the association between SUA/Cr and MetS in adults with overweight/obesity. Results: SUA/Cr levels were lower in non-MetS participants (OR: 2.159, 95% CI: 1.82 to 2.56; p < 0.001), and tended to rise with the increasing number of MetS components. Additionally, elevated SUA/Cr levels were associated with a higher risk of hypertension, hyperglycemia, and dyslipidemia. Conclusion: SUA/Cr levels were significantly associated with MetS and its components in Chinese adults with overweight/obesity.
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Background: Health-related quality of life (HRQoL) of androgenetic alopecia patients has become increasingly important, but the influencing factors associated with the different domains are poorly understood. Objective: This study aimed to investigate the influencing factors in HRQoL of androgenetic alopecia patients and identify its strongly associated domains. Patients and Methods: We enrolled 170 androgenetic alopecia patients. HRQoL was measured using the World Health Organization Quality of Life Brief Version (WHO-BREF), and Hairdex. Results: HRQoL was significantly impaired in patients <30 years, (WHO-BREF: P=0.022, Hairdex: P=0.004), less educated (WHO-BREF: P=0.021, Hairdex: P=0.003), single patients (Hairdex: P=0.023), and urban residence (Hairdex: P=0.043). By domains, those <30 years were impaired by physical health (P=0.038) and psychological (P=0.030) by WHO-BREF, and symptoms (P=0.002) and emotions (P=0.002) by Hairdex. Singles were impaired by symptoms (P=0.020), and emotions (P=0.009) by Hairdex. Less-educated individuals had impaired all domains in the WHO-BREF and Hairdex, except for physical health. Women had impaired symptoms (P=0.013) and stigmatization (P=0.041) in Hairdex. Conclusion: Androgenetic alopecia is associated with significantly reduced HRQoL in young, less educated, and single patients. Dermatologists should inquire about Quality of Life and appropriately support androgenetic alopecia patients.
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Progressively stringent regulations regarding vehicle emissions and fuel economy have spurred technology diversification in light-duty passenger vehicles (LDPVs). To assess the real-world emissions and fuel economy performances of hybrid electric vehicles (HEVs) compared to conventional internal combustion engine (ICE) vehicles, on-road measurements of ten gasoline, four diesel and six full hybrid LDPVs were performed using portable emissions measurement systems (PEMS) in Macao, China. The hot-running emission results indicate that the high emission risks of gasoline vehicles are associated with high mileage and old model years. Diesel vehicles are found to be the highest pollutant emitters in this study due to the intentional removal of aftertreatment systems. Under hot-running conditions, HEVs, as expected, could achieve carbon-reduction benefits of approximately 30 % (i.e., lower CO2 emissions and fuel consumption) compared to their conventional gasoline counterparts, while no measurable reduction in pollutant emissions was observed except in NOX (~70 % reduction). In contrast, the cold-start extra emissions (CSEEs) of CO2 reached 120-364 g/start for these HEVs, even exceeding the maximum values of conventional gasoline vehicles. However, the higher CO2 CSEEs of HEVs can be far offset by their hot-running emission reduction benefits. For tailpipe pollutants, the CSEEs of the HEVs were reduced by 21 %-68 % on average in comparison to those of conventional gasoline vehicles. Furthermore, strong correlations (R2 values of 0.69-0.89) between the road grades and relative emissions were observed. These results can provide necessary information regarding the improvement of future LDPV emission models and inventories.
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Poluentes Atmosféricos , Gasolina , Poluentes Atmosféricos/análise , Carbono , Dióxido de Carbono/análise , Gasolina/análise , Veículos Automotores , Emissões de Veículos/análiseRESUMO
Adipose-derived stem cells (ADSCs) play an important role in cell therapy and regenerative medicine. However, local nutritional deficiency often limits therapeutical effect of the transplanted cells. Acetyl l-carnitine (ALC) is a common energy metabolism regulator and free radical scavenger. This study investigated the effect of ALC on ADSCs exposed to severe serum-deprivation and explored the relative machanisms. Treating with 1 mM ALC improved proliferation and alleviated senescence of starved cells, accompanied with reduced reactive oxygen species (ROS) and increased protein expression of SOD1 and catalase. In addition, ALC inhibited apoptosis but increased starvation-induced autophagy, which might be related to the regulation of phases of dissociation of Bcl-2-Beclin1 and Bcl-2-Bax complexes. Evidence obtained by replacing ALC with N-acetylcysteine (N-AC) suggested that ROS might be the central inducer of autophagy, apoptosis and senescence. There was a difference between ALC and N-AC in the protection mechanism, that was, compared with N-AC, ALC maintained autophagy well at the same time as anti-oxidation. Inhibition of autophagy by 3-methyladenine (3-MA) partially offset the protective effect of ALC. However, despite low-level ROS and enhanced autophagy, ALC with high concentration (10 mM) markedly aggravated cell apoptosis and senescence, thus losing cytoprotection and even causing damage.
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Adipose-derived stem cells (ADSCs) are easily available and play an important role in regenerative medicine. In recent years, Cell spheroid models have been in the spotlight because of their various advantages and physiological proximity. Promoting the spreading of ADSCs spheroids may improve the therapeutic effect the transplanted ADSCs. In this study, we prepared autologous decellularized extracellular matrix (d-ECM) and ADSCs spheroids, and investigated in vitro spreading of the spheroids on the d-ECM-coated substrate. In addition, the effect of d-ECM powder (ECM-P) on the aggregation of ADSCs was analyzed in a three-dimensional (3D) culture system. The results showed that d-ECM accelerated the spreading of spheroids, and promoted the migration and proliferation of the surrounding monolayer cells, accompanied by ERK1/2 activation and an increase in the expression of MMP2 and MMP9. In addition, ECM-P facilitated the aggregation of free cells in 3D culture in a concentration-dependent way. The spheroid spreading and cell aggregation were both prevented by ERK1/2 selective inhibitor PD98059. Our data suggest that the d-ECM substrate and its derivant may regulate the transformation between ADSCs spheroids and the monolayer or free cells, and ERK1/2 signalling pathway may be involved in these processes.
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High viability and further adipogenic differentiation of adipose-derived stem cells (ADSCs) are fundamental for engraftment and growth of the transplanted adipose tissue. It has been demonstrated that extracellular matrix (ECM) regulates cell proliferation and differentiation by interacting with ERK1/2 signalling pathway. In this study, we prepared autologous decellularized extracellular matrix (d-ECM) and explored its effect on the proliferation and adipogenic ability of ADSCs in low serum culture. We found that 2% foetal bovine serum (FBS) in growth medium inhibited cell viability and DNA replication, and decreased mRNA and protein levels of PPARγ and C/EPBα compared with 10% FBS. Correspondingly, after 14-days adipogenic induction, cells cultured in 2% FBS possessed lower efficiency of adipogenesis and expressed less adipocyte differentiation markers ADIPOQ and aP2. On the contrary, the d-ECM-coated substrate continuously promoted the expression of PPARγ, and regulated the phosphorylation of ERK1/2 in different manners during differentiation. Pretreatment with ERK1/2 inhibitor PD98059 neutralized the effects of d-ECM, which suggested d-ECM might regulate the adipogenesis of ADSCs through ERK1/2-PPARγ pathway. In addition, d-ECM was revealed to regulate the transcription and expression of stemness-associated genes, such as OCT4, NANOG and SOX2, in the undifferentiated ADSCs, which might be related to the initiation of differentiation.