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1.
Cancer Lett ; 588: 216714, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38369003

RESUMO

Glioblastoma, the most prevalent malignant primary brain tumor, presents substantial treatment challenges because of its inherent aggressiveness and limited therapeutic options. Lymphopenia, defined as reduced peripheral blood lymphocyte count, commonly occurs as a consequence of the disease and its treatment. Recent studies have associated lymphopenia with a poor prognosis. Factors that contribute to lymphopenia include radiotherapy, chemotherapy, and the tumor itself. Patients who are female, older, using dexamethasone, or receiving higher doses of radiation therapy are particularly vulnerable to this condition. Several preclinical studies have explored the use of interleukin-7, a crucial cytokine for lymphocyte homeostasis, to restore lymphocyte counts and potentially rebuild the immune system to combat glioblastoma cells. With the development of recombinant interleukin-7 for prolonged activity in the body, various clinical trials are underway to explore this treatment in patients with glioblastoma. Our study provides a comprehensive summary of the incidence of lymphopenia, its potential biological background, and the associated clinical risk factors. Furthermore, we reviewed several clinical trials using IL-7 cytokine therapy in glioblastoma patients. We propose IL-7 as a promising immunotherapeutic strategy for glioblastoma treatment. We are optimistic that our study will enhance understanding of the complex interplay between lymphopenia and glioblastoma and will pave the way for the development of more effective treatment modalities.


Assuntos
Glioblastoma , Linfopenia , Humanos , Feminino , Masculino , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Interleucina-7/uso terapêutico , Interleucina-7/farmacologia , Linfopenia/etiologia , Linfopenia/patologia , Linfócitos , Imunoterapia/efeitos adversos
2.
ACS Appl Mater Interfaces ; 15(48): 56150-56157, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38011316

RESUMO

Tin monosulfide (SnS) is a two-dimensional layered semiconductor that exhibits in-plane ferroelectric order at very small thicknesses and is of interest in highly scaled devices. Here we report the epitaxial growth of SnS on hexagonal boron nitride (hBN) using a pulsed metal-organic chemical vapor deposition process. Lattice matching is observed between the SnS(100) and hBN{11̅0} planes, with no evidence of strain. Atomic force microscopy reveals superlubricity along the commensurate direction of the SnS/hBN interface, and first-principles calculations suggest that friction is controlled by the edges of the SnS islands, rather than interface interactions. Differential phase contrast imaging detects remnant polarization in SnS islands with domains that are not dictated by step-edges in the SnS. The growth of ferroelectric SnS on high quality hBN substrates is a promising step toward electrically switchable ferroelectric semiconducting devices.

3.
J Am Anim Hosp Assoc ; 59(5): 241-248, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37708476

RESUMO

It has been reported that hypertriglyceridemia can partially mediate between diabetes mellitus (DM) and pancreatitis in dogs, implying that another mediator, such as chronic hyperglycemia, might exist. Therefore, this study aimed to evaluate the relationship between hyperglycemia and serum canine pancreatic lipase immunoreactivity (cPLI) concentration in diabetic dogs. This retrospective cohort study included 26 client-owned diabetic dogs, divided according to their serum fructosamine levels (<500 µmol/L = well-controlled DM group; ≥500 µmol/L = untreated or poorly controlled DM group). Five of the 26 DM dogs (19.2%) had serum cPLI concentrations consistent with pancreatitis, among which two showed ultrasonographic evidence of pancreatitis without clinical signs. The serum cPLI concentrations (median [interquartile range]) were significantly higher in the untreated or poorly controlled group (520 µg/L [179.76-1000 µg/L]) than in the well-controlled group (77 µg/L [32.22-244.6 µg/L], P = 0.0147). The serum fructosamine concentration was positively correlated with the serum cPLI concentration (r = 0.4816; P = 0.0127). Multivariate analysis revealed serum triglyceride and fructosamine concentrations were associated with the serum cPLI concentration. In conclusion, this study suggests that chronic hyperglycemia may induce pancreatic inflammation in diabetic dogs; however, the clinical significance of increased cPLI concentration is unknown.


Assuntos
Diabetes Mellitus , Doenças do Cão , Hiperglicemia , Pancreatite , Cães , Animais , Frutosamina , Estudos Retrospectivos , Diabetes Mellitus/veterinária , Hiperglicemia/veterinária , Lipase , Pancreatite/veterinária
4.
Proc Natl Acad Sci U S A ; 120(3): e2216672120, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36630451

RESUMO

Cost-effective fabrication of mechanically flexible low-power electronics is important for emerging applications including wearable electronics, artificial intelligence, and the Internet of Things. Here, solution-processed source-gated transistors (SGTs) with an unprecedented intrinsic gain of ~2,000, low saturation voltage of +0.8 ± 0.1 V, and a ~25.6 µW power consumption are realized using an indium oxide In2O3/In2O3:polyethylenimine (PEI) blend homojunction with Au contacts on Si/SiO2. Kelvin probe force microscopy confirms source-controlled operation of the SGT and reveals that PEI doping leads to more effective depletion of the reverse-biased Schottky contact source region. Furthermore, using a fluoride-doped AlOx gate dielectric, rigid (on a Si substrate) and flexible (on a polyimide substrate) SGTs were fabricated. These devices exhibit a low driving voltage of +2 V and power consumption of ~11.5 µW, yielding inverters with an outstanding voltage gain of >5,000. Furthermore, electrooculographic (EOG) signal monitoring can now be demonstrated using an SGT inverter, where a ~1.0 mV EOG signal is amplified to over 300 mV, indicating significant potential for applications in wearable medical sensing and human-computer interfacing.


Assuntos
Inteligência Artificial , Condução de Veículo , Humanos , Dióxido de Silício , Fontes de Energia Elétrica , Óxidos , Polietilenoimina
5.
ACS Nano ; 17(1): 575-586, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36573755

RESUMO

Inks based on two-dimensional (2D) materials could be used to tune the properties of printed electronics while maintaining compatibility with scalable manufacturing processes. However, a very wide range of performances have been reported in printed thin-film transistors in which the 2D channel material exhibits considerable variation in microstructure. The lack of quantitative physics-based relationships between film microstructure and transistor performance limits the codesign of exfoliation, sorting, and printing processes to inefficient empirical approaches. To rationally guide the development of 2D inks and related processing, we report a gate-dependent resistor network model that establishes distinct microstructure-performance relationships created by near-edge and intersheet resistances in printed van der Waals thin-film transistors. The model is calibrated by analyzing electrical output characteristics of model transistors consisting of overlapping 2D nanosheets with varied thicknesses that are mechanically exfoliated and transferred. Kelvin probe force microscopy analysis on the model transistors leads to the discovery that the nanosheet edges, not the intersheet resistance, limit transport due to their impact on charge carrier depletion and scattering. Our model suggests that when transport in a 2D material network is limited by the near-edge resistance, the optimum nanosheet thickness is dictated by a trade-off between charged impurity screening and gate screening, and the film mobilities are more sensitive to variations in printed nanosheet density. Removal of edge states can enable the realization of higher mobilities with thinner nanosheets due to reduced junction resistances and reduced gate screening. Our analysis of the influence of nanosheet edges on the effective film mobility not only examines the prospects of extant exfoliation methods to achieve the optimum microstructure but also provides important perspectives on processes that are essential to maximizing printed film performance.

6.
Comput Math Organ Theory ; 29(1): 20-51, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34776754

RESUMO

We introduce the Urban Life agent-based simulation used by the Ground Truth program to capture the innate needs of a human-like population and explore how such needs shape social constructs such as friendship and wealth. Urban Life is a spatially explicit model to explore how urban form impacts agents' daily patterns of life. By meeting up at places agents form social networks, which in turn affect the places the agents visit. In our model, location and co-location affect all levels of decision making as agents prefer to visit nearby places. Co-location is necessary (but not sufficient) to connect agents in the social network. The Urban Life model was used in the Ground Truth program as a virtual world testbed to produce data in a setting in which the underlying ground truth was explicitly known. Data was provided to research teams to test and validate Human Domain research methods to an extent previously impossible. This paper summarizes our Urban Life model's design and simulation along with a description of how it was used to test the ability of Human Domain research teams to predict future states and to prescribe changes to the simulation to achieve desired outcomes in our simulated world.

7.
Front Cardiovasc Med ; 9: 1045742, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36531696

RESUMO

Background: Epicardial adipose tissue (EAT) plays a significant role in promoting atrial fibrillation (AF) due to its proinflammatory properties and anatomic proximity to the myocardium. We sought to assess whether left atrial (LA) EAT volume is associated with AF recurrence following catheter ablation. Methods: EAT was assessed via the 3D MRI Dixon sequence in 101 patients undergoing AF ablation. Patients were followed for arrhythmia recurrence. Results: During an average follow-up period of 1 year, post-ablation AF recurrence occurred in 31 (30.7%) patients. LA EAT index was higher in those with compared to without recurrence (20.7 [16.9, 30.4] vs. 13.7 [10.5, 20.1] mL/m2, p < 0.001), and so was LA volume index (66 [52.6, 77.5] vs. 49.9 [37.7, 61.8] mL/m2, p = 0.001). Cox regression analysis showed LA EAT (HR = 1.089; 95% CI: [1.049-1.131], p < 0.001) to be an independent predictor of post-ablation AF recurrence. The ROC curve for LA EAT index in the prediction of AF recurrence had an AUC of 0.77 (95% CI 0.68-0.86, p < 0.001) and showed an optimal cutoff value of 14.29 mL/m2 to identify patients at risk of post-ablation AF recurrence. Integrating LA EAT with clinical risk factors improved prediction of AF recurrence (AUC increased from 0.65 to 0.79, DeLong test p = 0.044). Kaplan-Meier analysis for recurrence-free survival showed a significant difference between two groups of patients identified by the optimal LA EAT index cutoff of 14.29 mL/m2 (log rank = 14.79; p < 0.001). Conclusion: EAT quantified using cardiac MRI, a reproducible and widely accessible imaging parameter, is a strong and independent predictor of post-ablation AF recurrence.

8.
ACS Appl Mater Interfaces ; 14(41): 46841-46849, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36195978

RESUMO

Excitonic properties in 2D heterobilayers are closely governed by charge transfer (CT) and excitonic energy transfer (ET) at van der Waals interfaces. Various means have been employed to modulate the interlayer CT and ET, including electrical gating and modifying interlayer spacing, but with limited extent in their controllability. Here, we report a novel method to modulate these transfers in the MoS2/WS2 heterobilayer by applying compressive strain under hydrostatic pressure. Raman and photoluminescence measurements, combined with density functional theory calculations, show pressure-enhanced interlayer interaction of the heterobilayer. Heterobilayer-to-monolayer photoluminescence intensity ratio (η) of WS2 decreases by five times up to ≈4 GPa, suggesting enhanced ET, whereas it increases by an order of magnitude at higher pressures and reaches almost unity. Theoretical calculations show that orbital switching and charge transfers in the heterobilayer's hybridized conduction band are responsible for the non-monotonic modulation of the transfers. Our findings provide a compelling approach toward effective mechanical control of CT and ET in 2D excitonic devices.

9.
Adv Mater ; 34(45): e2205871, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36039798

RESUMO

Thin-film transistors using metal oxide semiconductors are essential in many unconventional electronic devices. Nevertheless, further advances will be necessary to broaden their technological appeal. Here, a new strategy is reported to achieve high-performance solution-processed metal oxide thin-film transistors (MOTFTs) by introducing a metallic micro-island array (M-MIA) on top of the MO back channel, where the MO is a-IGZO (amorphous indium-gallium-zinc-oxide). Here Al-MIAs are fabricated using honeycomb cinnamate cellulose films, created by a scalable breath-figure method, as a shadow mask. For IGZO TFTs, the electron mobility (µe ) increases from ≈3.6 cm2 V-1 s-1 to near 15.6 cm2 V-1 s-1 for optimal Al-MIA dimension/coverage of 1.25 µm/51%. The Al-MIA IGZO TFT performance is superior to that of controls using compact/planar Al layers (Al-PL TFTs) and Au-MIAs with the same channel coverage. Kelvin probe force microscopy and technology computer-aided design simulations reveal that charge transfer occurs between the Al and the IGZO channel which is optimized for specific Al-MIA dimensions/surface channel coverages. Furthermore, such Al-MIA IGZO TFTs with a high-k fluoride-doped alumina dielectric exhibit a maximum µe of >50.2 cm2 V-1 s-1 . This is the first demonstration of a micro-structured MO semiconductor heterojunction with submicrometer resolution metallic arrays for enhanced transistor performance and broad applicability to other devices.

10.
Am J Cardiol ; 162: 116-121, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34903337

RESUMO

Our knowledge of the association between abdominal obesity (AO) and the risk of atrial fibrillation (AF) after adjusting for body mass index (BMI) is limited. We included 11,617 Black and White participants (mean age 63.0 ± 8.4 years) from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) national cohort study who were free of AF at baseline. A multivariable logistic regression model was used to estimate the odds ratio (OR) with 95% confidence interval (CI) of incident AF associated with AO. We also evaluated the association between waist circumference (WC) and incident AF. Over a median follow-up of 9.4 years, 999 participants developed AF. AO was associated with an increased risk of AF in a multivariable model adjusted for sociodemographic, lifestyle, and cardiovascular risk factors (OR 1.43, 95% CI 1.24 to 1.65, p <0.001). The association was attenuated after adjusting for BMI (OR 1.13, 95% CI 0.95 to 1.35, p = 0.16). There was no evidence of interaction between AO and incident AF by age category (age >65 vs age ≤65), gender, race, obesity, or BMI category. Conversely, a 10cm increase in WC was associated with a higher incidence of AF after controlling for BMI (OR 1.18 95% CI 1.09 to 1.29, p <0.001), in both nonobese (OR 1.14, 95% CI 1.03 to 1.28, p = 0.02) and obese (OR 1.26, 95% CI 1.11 to 1.42, p <0.001) people. In conclusion, there was an association between AO and incident AF, but the association was weakened after adjusting for BMI. There was a significant association between WC and incident AF, after taking other AF risk factors and BMI into account. WC is a potentially modifiable risk factor for AF, and further research is warranted to explore the effect of decreasing WC on the population AF burden.


Assuntos
Fibrilação Atrial/epidemiologia , Negro ou Afro-Americano/estatística & dados numéricos , Obesidade Abdominal/complicações , Obesidade Abdominal/etnologia , Acidente Vascular Cerebral/epidemiologia , População Branca/estatística & dados numéricos , Idoso , Índice de Massa Corporal , Estudos de Coortes , Feminino , Humanos , Incidência , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos , Circunferência da Cintura
11.
PLoS One ; 16(11): e0259031, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34727103

RESUMO

With the onset of COVID-19 and the resulting shelter in place guidelines combined with remote working practices, human mobility in 2020 has been dramatically impacted. Existing studies typically examine whether mobility in specific localities increases or decreases at specific points in time and relate these changes to certain pandemic and policy events. However, a more comprehensive analysis of mobility change over time is needed. In this paper, we study mobility change in the US through a five-step process using mobility footprint data. (Step 1) Propose the Delta Time Spent in Public Places (ΔTSPP) as a measure to quantify daily changes in mobility for each US county from 2019-2020. (Step 2) Conduct Principal Component Analysis (PCA) to reduce the ΔTSPP time series of each county to lower-dimensional latent components of change in mobility. (Step 3) Conduct clustering analysis to find counties that exhibit similar latent components. (Step 4) Investigate local and global spatial autocorrelation for each component. (Step 5) Conduct correlation analysis to investigate how various population characteristics and behavior correlate with mobility patterns. Results show that by describing each county as a linear combination of the three latent components, we can explain 59% of the variation in mobility trends across all US counties. Specifically, change in mobility in 2020 for US counties can be explained as a combination of three latent components: 1) long-term reduction in mobility, 2) no change in mobility, and 3) short-term reduction in mobility. Furthermore, we find that US counties that are geographically close are more likely to exhibit a similar change in mobility. Finally, we observe significant correlations between the three latent components of mobility change and various population characteristics, including political leaning, population, COVID-19 cases and deaths, and unemployment. We find that our analysis provides a comprehensive understanding of mobility change in response to the COVID-19 pandemic.


Assuntos
COVID-19 , Distanciamento Físico , Viagem , Humanos , Quarentena , Análise Espaço-Temporal , Estados Unidos
12.
ACS Omega ; 6(39): 25551-25561, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34632212

RESUMO

To increase the stability of cerium scavengers, we doped cerium oxide on mesoporous silica powders for the application of an oxidative stabilizer. The oxidation-reduction reaction involving hydroxyl radicals (•OH) is investigated with Fenton's test using eight types of Ce(IV)-mobile compositions of matter 41 (MCM-41) and Ce(III)-MCM-41 powder samples. As confirmed by X-ray photoelectron spectroscopy, the relative amount of Ce3+ inside the mesoporous samples decreases with the increasing time of treatment using the Fenton solution, whereas that of Ce4+ increases. 29Si CP-MAS NMR shows that the condensation of the siloxane bond varies according to the treating time up to 120 h. The mesoporous structure is also analyzed using synchrotron small-angle X-ray scattering and nitrogen adsorption. Further treatment with propane sulfonic acid ensured that the ionic conductivity of the sulfonated mesoporous silica did not decrease. The surface-modified mesoporous silica was incorporated in sulfonated poly(arylene ether sulfone) multiblock membranes. The sulfonated mesoporous silica could overcome the drawbacks of transition metal scavengers, such as a drop in ionic conductivity. Through experiments, we determined that the Ce-doped sulfonated mesoporous silica/sulfonated poly(arylene ether sulfone) composite membranes exhibit high oxidation stability when exposed to hydrogen peroxide and even higher proton conductivity than Nafion at a relative humidity over 60%.

13.
Hypertension ; 75(6): 1483-1490, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32362231

RESUMO

We evaluated the impact of intensive blood pressure control on the incidence of new-onset atrial fibrillation/flutter (AF) and the prognostic implications of preexisting and new-onset AF in SPRINT (Systolic Blood Pressure Intervention Trial) participants. New-onset AF was defined as occurrence of AF in 12-lead electrocardiograms after randomization in participants free of AF at baseline. Poisson regression modeling was used to calculate incident rates of new-onset AF. Multivariable-adjusted Cox proportional hazard models were used to evaluate the risk of adverse cardiovascular events (composite of myocardial infarction, non-myocardial infarction acute coronary syndrome, stroke, heart failure, or cardiovascular death). In 9327 participants, 8.45% had preexisting AF, and 1.65% had new-onset AF. The incidence of new-onset AF was 4.53 per 1000-person years, with similar rates in the standard and intensive treatment arms (4.95 versus 4.11 per 1000-person years; adjusted P=0.14). Participants with preexisting AF (adjusted hazard ratio, 1.83 [95% CI, 1.46-2.31]; P<0.001) and new-onset AF (adjusted hazard ratio, 2.45 [95% CI, 1.58-3.80]; P<0.001) had a greater risk for development of adverse cardiovascular events compared with those with no AF. Participants with preexisting AF who achieved blood pressure <120/80 mm Hg at 3 months continued have a poor prognosis (adjusted hazard ratio, 1.88 [95% CI, 1.32-2.70]; P=0.001) compared with those with no AF. Intensive blood pressure control does not diminish the incidence of new-onset AF in an older, high-risk, nondiabetic population. Both preexisting and new-onset AF have adverse prognostic implications. In participants with preexisting AF, residual cardiovascular risk is evident even with on-treatment blood pressure <120/80 mm Hg. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT01206062.


Assuntos
Anti-Hipertensivos/uso terapêutico , Fibrilação Atrial , Flutter Atrial , Determinação da Pressão Arterial , Doenças Cardiovasculares , Hipertensão , Fatores Etários , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Flutter Atrial/diagnóstico , Flutter Atrial/epidemiologia , Pressão Sanguínea/efeitos dos fármacos , Determinação da Pressão Arterial/métodos , Determinação da Pressão Arterial/normas , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/mortalidade , Eletrocardiografia/métodos , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Incidência , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Prognóstico
14.
J Clin Med Res ; 11(4): 247-255, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30937114

RESUMO

BACKGROUND: Thiazide diuretics are among the most widely prescribed antihypertensive agents. Given their photosensitizing effects, however, there are concerns that they may increase the risk of skin cancers. In this meta-analysis, we investigated an association between the use of thiazide diuretics and the risk of skin cancers. METHODS: We identified studies by searching three electronic databases (PubMed, EMBASE, and the Cochrane Library) from their inception to October 30, 2017. Nine relevant observational studies (seven case-control and two cohort studies) were included in this study. Since included studies were unlikely to be functionally equal, pooled estimates were calculated using random-effects meta-analysis. RESULTS: The use of thiazide diuretics was associated with an increased risk of squamous cell carcinoma (adjusted odds ratio (aOR), 1.86; 95% confidence interval (CI), 1.23 - 2.80) and marginally increased risk of basal cell carcinoma (aOR, 1.19; 95% CI, 1.02 - 1.38) and malignant melanoma (aOR, 1.14; 95% CI, 1.01 - 1.29). In the subgroup analysis, hydrochlorothiazide or hydrochlorothiazide combination medications were significantly associated with squamous cell carcinoma without significant heterogeneity among studies (aOR, 2.04; 95% CI, 1.79 - 2.33; Higgin's I2 value = 0.0 %; Q-statistics = 2.7, P value = 0.445). CONCLUSIONS: Our results suggested that the use of thiazide diuretics may be associated with an increased risk of skin cancers. This association was most prominent between the use of hydrochlorothiazide or hydrochlorothiazide combination medications and the risk of squamous cell carcinoma. Further studies are needed to confirm these findings.

15.
Circ Cardiovasc Qual Outcomes ; 11(7): e004224, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29991644

RESUMO

BACKGROUND: Multiple studies have attempted to identify the association between multivitamin/mineral (MVM) supplementation and cardiovascular disease (CVD) outcomes, but the benefits remain controversial. We performed a systematic review and meta-analysis of the associations between MVM supplementation and various CVD outcomes, including coronary heart disease (CHD) and stroke. METHODS AND RESULTS: We conducted a comprehensive search of Medline, Embase, and the Cochrane Library for studies published between January 1970 and August 2016. We included clinical trials and prospective cohort studies in the general population evaluating associations between MVM supplementation and CVD outcomes. Data extraction and quality assessment were independently conducted by 2 authors, and a third author resolved discrepancies. Eighteen studies with 2 019 862 participants and 18 363 326 person-years of follow-up were included in the analysis. Five studies specified the dose/type of MVM supplement and the rest did not. Overall, there was no association between MVM supplementation and CVD mortality (relative risk [RR], 1.00; 95% confidence interval [CI], 0.97-1.04), CHD mortality (RR, 1.02; 95% CI, 0.92-1.13), stroke mortality (RR, 0.95; 95% CI, 0.82-1.09), or stroke incidence (RR, 0.98; 95% CI, 0.91-1.05). There was no association between MVM supplements and CVD or CHD mortality in prespecified subgroups categorized by mean follow-up period, mean age, period of MVM use, sex, type of population, exclusion of patients with history of CHD, and adjustment for diet, adjustment for smoking, adjustment for physical activity, and study site. In contrast, MVM use did seem to be associated with a lower risk of CHD incidence (RR, 0.88; 95% CI, 0.79-0.97). However, this association did not remain significant in the pooled subgroup analysis of randomized controlled trials (RR, 0.97; 95% CI, 0.80-1.19). CONCLUSIONS: Our meta-analysis of clinical trials and prospective cohort studies demonstrates that MVM supplementation does not improve cardiovascular outcomes in the general population.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Suplementos Nutricionais , Minerais/uso terapêutico , Vitaminas/uso terapêutico , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/mortalidade , Suplementos Nutricionais/efeitos adversos , Combinação de Medicamentos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Minerais/efeitos adversos , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Vitaminas/efeitos adversos
17.
Atherosclerosis ; 257: 1-8, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28033543

RESUMO

BACKGROUND AND AIMS: TAC is associated with incident CVD and all-cause mortality. Nevertheless, the independent 10-year prognostic value of TAC in individuals with CAC = 0 beyond traditional risk factors is not well established. METHODS: 3415 MESA participants with baseline CAC = 0 were followed for CHD, CVD events and all-cause mortality. TAC was measured in the ascending and descending aorta in all participants and quantified using Agatston's score. Multivariable Cox proportional hazards regression models were used to study the associations between TAC and incident CHD, CVD events and all-cause mortality. Likelihood ratio tests were used to compare prediction models including traditional risk factors plus TAC versus risk factors alone. RESULTS: 406 participants (11.9%) had TAC>0 at baseline. Over a median follow-up of 11.3 years, unadjusted event rates per 1000 person-years were higher in TAC>0 than in TAC = 0 participants: CHD 2.18 vs. 2.03; CVD 6.85 vs. 3.42; all-cause mortality 12.84 vs. 4.96. However, in multivariable Cox regression analyses adjusting for CVD risk factors, neither TAC>0, TAC>100 nor log(TAC+1) were independently associated with any of the study outcomes, nor improved their prediction compared to traditional risk factors alone (p value of likelihood ratio tests >0.05). CONCLUSIONS: In a multi-ethnic, modern US population of asymptomatic individuals with CAC = 0 at baseline, the prevalence of TAC>0 was low, and TAC did not improve 10-year estimation of prognosis beyond traditional risk factors. In the presence of CAC = 0, measurement of TAC is unlikely to provide sufficient additional prognostic information to further improve risk assessment.


Assuntos
Aorta Torácica , Doenças da Aorta/mortalidade , Doença das Coronárias/mortalidade , Calcificação Vascular/mortalidade , Idoso , Idoso de 80 Anos ou mais , Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/etnologia , Aortografia/métodos , Doenças Assintomáticas , Causas de Morte , Angiografia por Tomografia Computadorizada , Angiografia Coronária/métodos , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/etnologia , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Prevalência , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Estados Unidos/epidemiologia , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/etnologia
18.
ACS Nano ; 10(10): 9543-9549, 2016 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-27704779

RESUMO

Black phosphorus has been recently suggested as a very promising material for use in 2D field-effect transistors. However, due to its poor stability under ambient conditions, this material has not yet received as much attention as for instance MoS2. We show that the recently demonstrated Al2O3 encapsulation leads to highly stable devices. In particular, we report our long-term study on highly stable black phosphorus field-effect transistors, which show stable device characteristics for at least eight months. This high stability allows us to perform a detailed analysis of their reliability with respect to hysteresis as well as the arguably most important reliability issue in silicon technologies, the bias-temperature instability. We find that the hysteresis in these transistors depends strongly on the sweep rate and temperature. Moreover, the hysteresis dynamics in our devices are reproducible over a long time, which underlines their high reliability. Also, by using detailed physical models for oxide traps developed for Si technologies, we are able to capture the channel electrostatics of the black phosphorus FETs and determine the position of the defect energy band. Finally, we demonstrate that both hysteresis and bias-temperature instabilities are due to thermally activated charge trapping/detrapping by oxide traps and can be reduced if the device is covered by Teflon-AF.

19.
Nano Lett ; 16(11): 6931-6938, 2016 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-27775368

RESUMO

We report the first direct dry transfer of a single-crystalline thin film grown by molecular beam epitaxy. A double cantilever beam fracture technique was used to transfer epitaxial bismuth thin films grown on silicon (111) to silicon strips coated with epoxy. The transferred bismuth films retained electrical, optical, and structural properties comparable to the as-grown epitaxial films. Additionally, we isolated the bismuth thin films on freestanding flexible cured-epoxy post-transfer. The adhesion energy at the bismuth/silicon interface was measured to be ∼1 J/m2, comparable to that of exfoliated and wet transferred graphene. This low adhesion energy and ease of transfer is unexpected for an epitaxially grown film and may enable the study of bismuth's unique electronic and spintronic properties on arbitrary substrates. Moreover, this method suggests a route to integrate other group-V epitaxial films (i.e., phosphorus) with arbitrary substrates, as well as potentially to isolate bismuthene, the atomic thin-film limit of bismuth.

20.
Am J Cardiol ; 118(5): 725-32, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27394411

RESUMO

Ventricular premature complexes (VPCs) during stress testing in the general population are commonly seen in clinical practice, but their prognostic value is not well understood. A comprehensive literature search of MEDLINE, Embase, and the Cochrane Library from January 1970 to May 2015 was conducted. Observational cohort studies on general populations evaluating the association between exercise-induced VPCs and all-cause or cardiovascular mortality were included in the analysis. Nine studies comprising 62,488 participants comparing clinical outcomes of patients with and without exercise-induced VPCs were included. The overall combined relative risks (RRs) for all-cause mortality and cardiovascular mortality in patients with exercise-induced VPCs were 1.41 (95% CI 1.23 to 1.61) and 1.86 (95% CI 1.51 to 2.30), respectively. In subgroup analysis, both frequent VPCs (RR 1.35, 95% CI 1.14 to 1.60) and infrequent VPCs (RR 1.57, 95% CI 1.13 to 2.18) were associated with an adverse outcome. VPCs during recovery were associated with an increased risk of death (RR 1.55, 95% CI 1.22 to 1.96). VPCs during exercise did not achieve statistical significance (RR 1.14, 95% CI 0.96 to 1.34), but only a few studies were included in the analysis. In conclusion, our meta-analysis suggests that exercise-induced VPCs in the general population significantly increase the risk of total mortality and cardiovascular mortality. Our study calls for further studies to assess the prognostic significance of exercise-induced VPCs and the utility of efforts to reduce the VPC burden to improve the clinical outcome.


Assuntos
Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Teste de Esforço/efeitos adversos , Complexos Ventriculares Prematuros/etiologia , Complexos Ventriculares Prematuros/mortalidade , Medicina Baseada em Evidências , Humanos , Estudos Observacionais como Assunto , Prognóstico , Medição de Risco , Fatores de Risco , Estados Unidos/epidemiologia , Complexos Ventriculares Prematuros/complicações
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