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1.
Age Ageing ; 52(11)2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37962418

RESUMO

This study investigated the risk of post-COVID-19 conditions in older patients with COVID-19 compared to those with influenza, and how age impacts this relationship. Patients aged ≥65 years with COVID-19 or influenza were identified using the TriNetX network. The risk of post-COVID-19 conditions was compared between survivors of COVID-19 and influenza, followed by a comparison of post-COVID-19 conditions risk between patients aged 65-74 years and those aged over 75 years. Compared with influenza survivors, post-COVID-19 conditions were significantly more prevalent in patients with COVID-19 (hazard ratio [HR], 1.534; 95% confidence interval [CI]: 1.405-1.675). Specifically, COVID-19 survivors have a significantly higher risk of experiencing abnormal breathing (HR, 2.052; 95% CI: 1.757-2.397), fatigue (HR, 1.587; 95% CI: 1.322-1.905), anxiety/depression (HR, 1.587; 95% CI: 1.322-1.905), cognitive symptoms (HR, 1.667; 95% CI: 1.295-2.146) and cough (HR, 1.250; 95% CI: 1.006-1.553) compared with the influenza group. Contrastingly, no significant difference was observed in the risk of any post-COVID-19 condition between COVID-19 survivors aged 65-74 years and those aged over 75 years (HR, 0.994; 95% CI: 0.920-1.073). However, a lower incidence of cognitive symptoms was observed in patients aged 65-74 years compared to those aged ≥75 years (HR, 0.543; 95% CI: 0.445-0.661). In conclusion, compared with influenza, older patients have a higher risk of developing post-COVID-19 conditions after SARS-CoV-2 infection, and those aged over ≥75 years may have an increased risk of developing cognitive symptoms compared to those aged 65-74 years.


Assuntos
COVID-19 , Influenza Humana , Humanos , Idoso , COVID-19/epidemiologia , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , SARS-CoV-2 , Depressão/diagnóstico , Depressão/epidemiologia , Análise de Dados
2.
Int J Mol Sci ; 23(10)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35628510

RESUMO

Leptin is a crucial regulator of metabolism and energy homeostasis in mammals. Many studies have investigated the impacts of leptin on human cancers, such as proliferation and metastasis. However, the mechanisms underlying leptin-mediated regulation of lipid metabolism in nasopharyngeal carcinoma (NPC) remain incompletely understood. In the current study, leptin downregulation ameliorated lipid accumulation, triglyceride, and cholesterol levels. Mechanistically, diminished leptin by siRNA not only inhibited sterol regulatory element-binding protein 1 (SREBP1), a master regulator of lipid metabolism, at the mRNA and protein levels, but also reduced SREBP1 downstream target expressions, such as fatty acid synthase (FASN) and stearoyl-CoA desaturase-1 (SCD1), in NPC cells. In addition, leptin expression could modulate the promoter activity of SREBP1. We also found that pharmacological inhibition of poly-ADP ribose polymerase-γ (PPAR-γ) resulted in increased SREBP1 expression in leptin-depleted NPC cells. Functionally, SREBP1 overexpression overcame the effects of leptin-silencing attenuated triglyceride level, cholesterol level and cell survival in NPC cells. Taken together, our results demonstrate that leptin is an important regulator of lipid metabolism in NPC cells and might could be a potential therapeutic target for treatment of NPC patients.


Assuntos
Leptina , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Proteína de Ligação a Elemento Regulador de Esterol 1 , Colesterol , Inativação Gênica , Humanos , Leptina/genética , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triglicerídeos
3.
3D Print Addit Manuf ; 10(5): 1055-1063, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37886416

RESUMO

In this study, normal and floating builds of Ti-6Al-4V were fabricated by electron beam additive manufacturing. The effects of the spatial arrangement on the microstructure, mechanical properties, and surface roughness of the parts were investigated. Both the normal and floating builds exhibited an α+ß lamellar microstructure, but the normal builds had finer grains compared to the floating builds. The microstructural characteristics were correlated with the thermal history, specifically the cooling rate, resulting from the connection plate (S45C for the normal builds and the powder bed for the floating builds). The compressive yield strength and hardness of the normal builds were higher than those of the floating builds, regardless of build location owing to the grain refinement effects on the normal builds. The top surface (TS) of the sample was smoothest, and the lateral surface of the sample was the roughest for both the normal and floating builds; however, the roughness of the TS and bottom surface samples did not differ significantly between normal and floating builds. There were no noticeable differences in the microstructure and mechanical properties of the builds in five different positions, that is, the center and four corners. Finally, these findings were used to develop a set of conceptual spatial arrangement designs, including floating builds, to optimize the microstructure and mechanical properties.

4.
Comput Struct Biotechnol J ; 21: 4030-4043, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37664175

RESUMO

Esophageal squamous cell carcinoma (ESCC), one of the most lethal cancers, has become a global health issue. Stearoyl-coA desaturase 1 (SCD1) has been demonstrated to play a crucial role in human cancers. However, pan-cancer analysis has revealed little evidence to date. In the current study, we systematically inspected the expression patterns and potential clinical outcomes of SCD1 in multiple human cancers. SCD1 was dysregulated in several types of cancers, and its aberrant expression acted as a diagnostic biomarker, indicating that SCD1 may play a role in tumorigenesis. We used ESCC as an example to demonstrate that SCD1 was dramatically upregulated in tumor tissues of ESCC and was associated with clinicopathological characteristics in ESCC patients. Furthermore, Kaplan-Meier analysis showed that high SCD1 expression was correlated with poor progression-free survival (PFS) and disease-free survival (DFS) in ESCC patients. The protein-protein interaction (PPI) network and module analysis by PINA database and Gephi were performed to identify the hub targets. Meanwhile, the functional annotation analysis of these hubs was constructed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Functionally, the gain-of-function of SCD1 in ESCC cells promoted cell proliferation, migration, and invasion; in contrast, loss-of-function of SCD1 in ESCC cells had opposite effects. Bioinformatic, QPCR, Western blotting and luciferase assays indicated that SCD1 was a direct target of miR-181a-5p in ESCC cells. In addition, gain-of-function of miR-181a-5p in ESCC cells reduced the cell growth, migratory, and invasive abilities. Conversely, inhibition of miR-181a-5p expression by its inhibitor in ESCC cells had opposite biological effects. Importantly, reinforced SCD1 in miR-181a-5p mimic ESCC transfectants reversed miR-181a-5p mimic-prevented malignant phenotypes of ESCC cells. Taken together, these results indicate that SCD1 expression influences tumor progression in a variety of cancers, and the miR-181a-5p/SCD1 axis may be a potential therapeutic target for ESCC treatment.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34200576

RESUMO

Policymakers and relevant public health authorities can analyze people's attitudes towards public health policies and events using sentiment analysis. Sentiment analysis focuses on classifying and analyzing text sentiments. A Twitter sentiment analysis has the potential to monitor people's attitudes towards public health policies and events. Here, we explore the feasibility of using Twitter data to build a surveillance system for monitoring people's attitudes towards public health policies and events since the beginning of the COVID-19 pandemic. In this study, we conducted a sentiment analysis of Twitter data. We analyzed the relationship between the sentiment changes in COVID-19-related tweets and public health policies and events. Furthermore, to improve the performance of the early trained model, we developed a data preprocessing approach by using the pre-trained model and early Twitter data, which were available at the beginning of the pandemic. Our study identified a strong correlation between the sentiment changes in COVID-19-related Twitter data and public health policies and events. Additionally, the experimental results suggested that the data preprocessing approach improved the performance of the early trained model. This study verified the feasibility of developing a fast and low-human-effort surveillance system for monitoring people's attitudes towards public health policies and events during a pandemic by analyzing Twitter data. Based on the pre-trained model and early Twitter data, we can quickly build a model for the surveillance system.


Assuntos
COVID-19 , Mídias Sociais , Atitude , Política de Saúde , Humanos , Pandemias , SARS-CoV-2
6.
Materials (Basel) ; 14(23)2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34885622

RESUMO

Ti6Al4V specimens with porous structures can be fabricated by additive manufacturing to obtain the desired Young's modulus. Their mechanical strength and deformation behavior can be evaluated using finite element analysis (FEA), with various models and simulation methodologies described in the existing literature. Most studies focused on the evaluation accuracy of the mechanical strength and deformation behavior using complex models. This study presents a simple elastic model for brittle specimens followed by an electron beam additive manufacturing (EBAM) process to predict the initial crack site and threshold of applied stress related to the failure of cubic unit lattice structures. Six cubic lattice specimens with different porosities were fabricated by EBAM, and compression tests were performed and compared to the FEA results. In this study, two different types of deformation behavior were observed in the specimens with low and high porosities. The adopted elastic model and the threshold of applied stress calculated via FEA showed good capabilities for predicting the initial crack sites of these specimens. The methodology presented in this study should provide a simple yet accurate method to predict the fracture initiation of porous structure parts.

7.
Materials (Basel) ; 13(7)2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32224887

RESUMO

Selective Electron Beam Additive Manufacturing (SEBAM) is a promising powder bed fusion additive manufacturing technique for titanium alloys that select particular area melting in different energy density for producing complexly shaped biomedical devices. For most commercial Ti6Al4V porous medical devices, the gradient energy density is usually applied to manufacture in one component during the SEBAM process which selects different energy density built on particular zones. This paper presents gradient energy density base characterization study on an SEBAM built rectangular specimen with a size of 3 mm × 20 mm × 60 mm. The specimen was divided into three zones were built in gradient energy density from 16 to 26.5 J/mm3. The microstructure and mechanical properties were investigated by means of scanning electron microscopy, X-ray diffraction, transmission electron microscopy and mechanical test. The α' martensitic and lack of fusion were observed in the low energy density (LED) built zone. However, no α' phase and no irregular pores were observed both in overlap energy density (OED) and high energy density (HED) built zones located at the middle and bottom of the specimen respectively. This implies the top location and lower energy density have positive effects on the cooling rate but negative effects on densification. The subsequence mechanical properties result also supports this point. Moreover, the intermetallic Ti3Al found in the bottom may be due to the heat transfer from the following melting layer. Furthermore, the microstructure evolution in gradient energy built zones is discussed based on the findings of the microstructure and thermal history correlation analysis.

8.
J Vis Exp ; (150)2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31475962

RESUMO

Friction stir spot welding (FSSW), a derivative of friction stir welding (FSW), is a solid-state welding technique that was developed in 1991. An industry application was found in the automotive industry in 2003 for the aluminum alloy that was used in the rear doors of automobiles. Friction stir spot welding is mostly used in Al alloys to create lap joints. The benefits of friction stir spot welding include a nearly 80% melting temperature that lowers the thermal deformation welds without splashing compared to resistance spot welding. Friction stir spot welding includes 3 steps: plunging, stirring, and retraction. In the present study, other materials including high strength steel are also used in the friction stir welding method to create joints. DP780, whose traditional welding process involves the use of resistance spot welding, is one of several high strength steel materials used in the automotive industry. In this paper, DP780 was used for friction stir spot welding, and its microstructure and microhardness were measured. The microstructure data showed that there was a fusion zone with fine grain and a heat effect zone with island martensite. The microhardness results indicated that the center zone exhibited a greater degree of hardness compared with the base metal. All data indicated that the friction stir spot welding used in dual phase steel 780 can create a good lap joint. In the future, friction stir spot welding can be used in high-strength steel welding applied in industrial manufacturing processes.


Assuntos
Fricção , Aço/química , Soldagem/métodos , Ligas/química , Ligas/normas , Alumínio/química , Alumínio/normas , Dureza , Aço/normas
9.
Eur Geriatr Med ; 10(5): 777-784, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34652710

RESUMO

PURPOSE: This study was conducted to clarify the long-term mortality in the older population with chronic pain (CP), which is still unclear. METHODS: We identified 17,568 older participants (aged ≥ 65 years) with CP and an identical number of comparison cohort without CP matched 1:1 by age and sex between 1996 and 2000 from the Taiwan National Health Insurance Research Database. Causes of CP, underlying comorbidities, living areas, and mortality were collected for analyses. The long-term mortality and the causes of mortality were compared between the two cohorts through follow-up since 2000 until 2015. RESULTS: The mean age (± standard deviation) was 73.5 ± 5.7 years, and female participants comprised 55.1% in both cohorts. The most common causes of CP were osteoarthritis (24.2%), spinal disorders (22.4%), peripheral vascular diseases (14.0%), and osteoporosis (9.5%). Older participants with CP had an increased rate of long-term mortality compared to that among their counterparts without CP after adjusting for the underlying comorbidities and the causes of CP (adjusted hazard ratio [AHR]: 1.18; 95% confidence interval [CI] 1.14-1.21). The increased mortality rate was observed even after the follow-up of 6 years (AHR 1.15; 95% CI 1.10-1.20). No significant difference was observed in the causes of mortality between the two cohorts. The most common cause of mortality was malignancy, followed by cardiovascular and cerebrovascular diseases. CONCLUSIONS: Chronic pain was associated with an increased rate of long-term mortality in the older population. Early detection and intervention for treating CP are suggested for this population.

10.
Nanotoxicology ; 13(5): 597-605, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30729842

RESUMO

Engineered nanomaterials are rapidly becoming an essential component of modern technology. Thousands of tons of nanomaterials are manufactured, used, and subsequently released into the environment annually. While the presence of these engineered nanomaterials in the environment has profound effects on various biological systems in the short term, little work has been done to understand their consequences over long, evolutionary timescales. The evolution of multicellularity is a critical step in the origin of complex life on Earth and a unique strategy for microorganisms to alleviate adverse environmental impacts, yet the selective pressures that favor the evolution of multicellular groups remain poorly understood. Here, we show that engineered nanomaterials, specifically copper oxide nanoparticles (CuO NPs), promote the evolution of undifferentiated multicellularity in Baker's yeast (Saccharomyces cerevisiae strain Y55). Transcriptomic analysis suggests that multicellularity mitigates the negative effects of CuO NPs in yeast cells and shifts their metabolism from alcoholic fermentation towards aerobic respiration, potentially increasing resource efficiency and providing a fitness benefit during CuO NP exposure. Competition assays also confirm that the multicellular yeast possesses a fitness advantage when exposed to CuO NPs. Our results, therefore, demonstrate that nanoparticles can have profound and unexpected evolutionary consequences, underscoring the need for a more comprehensive understanding of the long-term biological impacts of nanomaterial pollution.


Assuntos
Evolução Biológica , Cobre/toxicidade , Nanopartículas/toxicidade , Saccharomyces cerevisiae/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Transcriptoma/efeitos dos fármacos
11.
Sci Rep ; 8(1): 13776, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30213990

RESUMO

The nickel-titanium alloy (57Ni-43Ti in wt%) was atomized by the plasma rotating electrode process (PREP). The PREP parameters such as plasma arc current, rotating electrode speed with corresponding PREP powder size range in weight percentage analysis, powder morphology and biocapability of cells were studied by scanning electron microscopies, Inductively Coupled Plasma and X-ray diffraction techniques. From the electrode of the produced powders, the composition has no obviously changes. Weight percentage up to 31.8% of the range under 300 µm while the rotation electrode speed increase to 12k rpm. Spherical and flat with smooth surface were observed in different size range. Brittle phase was not observed of XRD data. The nitinol powder has high biocapability with cells showed no cytotoxicity and well cell adhesion in the in vivo assay.


Assuntos
Ligas/química , Níquel/química , Pós/síntese química , Titânio/química , Engenharia Biomédica , Adesão Celular , Linhagem Celular , Eletrodos , Humanos , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Difração de Raios X
12.
J Chem Phys ; 122(20): 204708, 2005 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-15945765

RESUMO

Dense tetragonal (t)-ZrO(2) nanocondensates were synthesized under very rapid heating and cooling by pulsed Nd-YAG (YAG--yttrium aluminum garnet) laser ablation with oxygen background gas and characterized by electron diffraction. The t-ZrO(2) nanoparticles with a residual stress up to about 5 GPa tended to form deformation twins/faults upon local electron dosage. By contrast, the t-ZrO(2) nanoparticles formed at an-order-of-magnitude higher power have a residual stress above 6 GPa and tended to transform into a metastable cubic (c) phase vulnerable to amorphization. The relaxation/transformation of the self-constrained t-ZrO(2) nanoparticles can be rationalized by a lowering of internal energy under the influence of resolved shear stress and local electron heating.

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