Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 88
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Transpl Int ; 36: 11552, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663524

RESUMO

Although the association between post-transplant malignancy (PTM) and immunosuppressive therapy after organ transplantation has been studied, an integrated review of PTM after lung transplantation is lacking. We investigated the incidence and types of de novo PTM and its impact on survival following double lung transplantation (DLT). The incidence and type of PTM as well as the annual and cumulative risks of each malignancy after DLT were analyzed. The overall survival (OS) of recipients with or without PTM was compared by the Kaplan-Meier survival method and landmark analysis. There were 5,629 cases (23.52%) with 27 types of PTMs and incidences and OS varied according to the types of PTMs. The recipients with PTM showed a significantly longer OS than those without PTM (p < 0.001). However, while the recipients with PTM showed significantly better OS at 3, and 5 years (p < 0.001, p = 0.007), it was worse at the 10-year landmark time (p = 0.013). And the single PTM group showed a worse OS rate than the multiple PTM group (p < 0.001). This comprehensive report on PTM following DLT can help understand the risks and timing of PTM to improve the implementation of screening and treatment.


Assuntos
Terapia de Imunossupressão , Transplante de Pulmão , Neoplasias , Incidência , Risco , Terapia de Imunossupressão/efeitos adversos , Neoplasias/classificação , Neoplasias/epidemiologia , Neoplasias/mortalidade , Humanos , Masculino , Adulto , Pessoa de Meia-Idade
2.
Clin Infect Dis ; 73(11): e4179-e4188, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-32717066

RESUMO

BACKGROUND: Nonsteroidal antiinflammatory drugs (NSAIDs) may exacerbate coronavirus disease 2019 (COVID-19) and worsen associated outcomes by upregulating the enzyme that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) binds to in order to enter cells. METHODS: We conducted a cohort study using South Korea's nationwide healthcare database, which contains data for all individuals who received a COVID-19 test (n = 69 793) as of 8 April 2020. We identified adults hospitalized with COVID-19, where cohort entry was the date of hospitalization. NSAID users were those prescribed NSAIDs in the 7 days before and including cohort entry, and nonusers were those not prescribed NSAIDs during this period. Our primary outcome was a composite of in-hospital death, intensive care unit admission, mechanical ventilation use, and sepsis; our secondary outcomes were cardiovascular complications and acute renal failure. We conducted logistic regression analysis to estimate odds ratio (OR) with 95% confidence intervals (CIs) using inverse probability of treatment weighting to minimize confounding. RESULTS: Of 1824 adults hospitalized with COVID-19 (mean age, 49.0 years; female, 59%), 354 were NSAID users and 1470 were nonusers. Compared with nonuse, NSAID use was associated with increased risks of the primary composite outcome (OR, 1.54; 95% CI, 1.13-2.11) but insignificantly associated with cardiovascular complications (OR, 1.54; 95% CI, 0.96-2.48) or acute renal failure (OR, 1.45; 95% CI, 0.49-4.14). CONCLUSIONS: While awaiting the results of confirmatory studies, we suggest NSAIDs be used with caution for COVID-19 patients as the harms associated with their use may outweigh their benefits.


Assuntos
COVID-19 , Preparações Farmacêuticas , Anti-Inflamatórios não Esteroides/efeitos adversos , Estudos de Coortes , Feminino , Mortalidade Hospitalar , Hospitalização , Humanos , Pessoa de Meia-Idade , SARS-CoV-2
3.
J Am Chem Soc ; 142(12): 5583-5593, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32111116

RESUMO

To understand the unexpected and puzzling long-term stability of nanoscale gas bubbles, it is crucial to probe their nature and intrinsic properties. We report herein synchrotron-based scanning transmission X-ray microscopy (STXM) evidence of highly condensed oxygen gas molecules trapped as surface nanobubbles. Remarkably, the analysis of absorption spectra of a single nanobubble revealed that the oxygen density inside was 1-2 orders of magnitude higher than that in atmospheric pressure, and these bubbles were found in a highly saturated liquid environment with the estimated oxygen concentration to be hundreds of times higher than the known oxygen solubility in equilibrium. Molecular dynamics simulations were performed to investigate the stability of surface nanobubbles on a heterogeneous substrate in gas-oversaturated water. These results indicated that gas molecules within confinement such as the nanobubbles could maintain a dense state instead of the ideal gas state, as long as their surrounding liquid is supersaturated. Our findings should help explain the surprisingly long lifetime of the nanobubbles and shed light on nanoscale gas aggregation behaviors.

4.
J Synchrotron Radiat ; 25(Pt 3): 878-884, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29714200

RESUMO

A scanning transmission X-ray microscope is operational at the 10A beamline at the Pohang Light Source. The 10A beamline provides soft X-rays in the photon energy range 100-2000 eV using an elliptically polarized undulator. The practically usable photon energy range of the scanning transmission X-ray microscopy (STXM) setup is from ∼150 to ∼1600 eV. With a zone plate of 25 nm outermost zone width, the diffraction-limited space resolution, ∼30 nm, is achieved in the photon energy range up to ∼850 eV. In transmission mode for thin samples, STXM provides the element, chemical state and magnetic moment specific distributions, based on absorption spectroscopy. A soft X-ray fluorescence measurement setup has been implemented in order to provide the elemental distribution of thicker samples as well as chemical state information with a space resolution of ∼50 nm. A ptychography setup has been implemented in order to improve the space resolution down to 10 nm. Hardware setups and application activities of the STXM are presented.

5.
Phys Chem Chem Phys ; 19(9): 6397-6405, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28197617

RESUMO

Correlations among the B-O6 octahedra distortions, existing polymorphous phases, band structures and electronic conductivities of ABO3 perovskites are matters for debate and require a deep understanding of their local atomic/electronic structures and diverse assets. In this study, to illustrate the distortion in V-O6 octahedra and its implication on the band structure and electronic properties, spectroscopic investigations on the RF-sputtering grown insulating SrVO3 thin films were employed using X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). V K-edge and V L3,2-edge XANES, along with atomic multiplet calculations, have confirmed the 4+ oxidation state of V ions in the pristine and annealed SrVO3 thin films. Lower t2g/eg peak intensity ratio and smaller energy separation between t2g and eg peaks in the O K-edge XANES spectra, compared to the VO2 reference sample, have confirmed a larger V-O6 distortion in the orthorhombic SrVO3 thin films. Moreover, from the EXAFS data analysis, the local orthorhombic structure has been identified in the pristine and annealed SrVO3 thin films, compelling significant distortion in the V-O6 octahedra. Dimerization in the vanadium chains and V-V twisting, caused by V-O6 octahedra distortion, manifests a miscellaneous ligand field interaction between O 2p and V 3d orbitals and facilitates (i) a larger separation between the bonding and antibonding d‖ orbitals and (ii) an upward shift of the π* band in the band structure, leading to larger band gaps in the insulating SrVO3 thin films. Our spectroscopy results may open up new avenues for the mechanism of insulating/conducting character in other complicated perovskite materials using XANES-EXAFS.

6.
Cardiovasc Diabetol ; 15(1): 122, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27565571

RESUMO

BACKGROUND: Acid-base imbalance has been reported to increase incidence of hypertension and diabetes. However, the association between diet-induced acid load and cardiovascular disease (CVD) risk in the general population has not been fully investigated. METHODS: This was a population-based, retrospectively registered cross-sectional study using nationally representative samples of 11,601 subjects from the Korea National Health and Nutrition Examination Survey 2008-2011. Individual CVD risk was evaluated using atherosclerotic cardiovascular disease (ASCVD) risk equations according to 2013 ACC/AHA guideline assessment in subjects aged 40-79 without prior CVD. Acid-base status was assessed with both the potential renal acid load (PRAL) and the dietary acid load (DAL) scores derived from nutrient intake. RESULTS: Individuals in the highest PRAL tertile had a significant increase in 10 year ASCVD risks (9.6 vs. 8.5 %, P < 0.01) and tended to belong to the high-risk (10 year risk >10 %) group compared to those in the lowest PRAL tertile (odds ratio [OR] 1.23, 95 % confidence interval [CI] 1.22-1.35). The association between higher PRAL score and high CVD risk was stronger in the middle-aged group. Furthermore, a multiple logistic regression analysis also demonstrated this association (OR 1.20 95 % CI 1.01-1.43). Subgroup analysis stratified obesity or exercise status; individuals in unhealthy condition with lower PRAL scores had comparable ASCVD risk to people in the higher PRAL group that were in favorable physical condition. In addition, elevated PRAL scores were associated with high ASCVD risk independent of obesity, exercise, and insulin resistance, but not sarcopenia. Similar trends were observed with DAL scores. CONCLUSION: Diet-induced acid load was associated with increased risk of CVD, independent of obesity and insulin resistance.


Assuntos
Equilíbrio Ácido-Base , Desequilíbrio Ácido-Base/epidemiologia , Ácidos/efeitos adversos , Doenças Cardiovasculares/epidemiologia , Dieta/efeitos adversos , Desequilíbrio Ácido-Base/diagnóstico , Desequilíbrio Ácido-Base/fisiopatologia , Adulto , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Distribuição de Qui-Quadrado , Comorbidade , Estudos Transversais , Feminino , Humanos , Concentração de Íons de Hidrogênio , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Avaliação Nutricional , Inquéritos Nutricionais , Razão de Chances , República da Coreia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
7.
Phys Chem Chem Phys ; 17(44): 30065-75, 2015 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-26499907

RESUMO

Ce1-xEuxO2 (0 ≤x≤ 0.3) nanoparticles (NPs) were synthesized by the chemical precipitation method. The microstructures and morphology were characterized by synchrotron X-ray diffraction and high resolution transmission electron microscopy. X-ray absorption near edge structure (XANES) spectra at the Eu M5,4-edge and atomic-multiplet calculations revealed that Eu(3+) was predominantly present in the CeO2 lattice and Eu(2+) was negligibly present within the entire doping range. The detailed analysis of the Ce M5,4-edge and the O K-edge has shown strong dependence of the Ce(3+)/Ce(4+) ratio and oxygen vacancy with Eu content. Extended X-ray absorption fine structure (EXAFS) spectra at the Ce K-edge, along with theoretical fitting, have shown systematic variation in the coordination number, bond length and Debye-Waller factor with Eu doping. A blue shift in the absorption edge was observed which implies a net increase in the charge transfer gap between the O 2p and Ce 4f bands due to the increased number of Ce(3+) ions in the Eu doped samples. The excitation and emission spectra of pure CeO2 NPs did not show any photoluminescence (PL) characteristic; however, Ce1-xEuxO2 (x = 0.1-0.3) NPs showed significant improvements in the 4f-4f, (5)D0-(7)F2 and (5)D0-(7)F1 transitions induced luminescence properties. Eu doping has two major effects on the electronic structure and optical properties of CeO2 NPs: the first, at an Eu content of 10 mol%, is the formation of Ce(4+)-O-Eu(3+) networks, i.e., Eu(3+) ions substitute the Ce(4+) ions and introduce oxygen vacancies and Ce(3+) ions in the host lattice, which favors the (5)D0-(7)F2 induced PL properties. The other, at an Eu doping over 10 mol%, is the formation of both Ce(4+)-O-Eu(3+) and Ce(3+)-O-Eu(3+), i.e., Eu(3+) ions not only take substitutional sites of Ce(4+) ions but also replace a fraction of Ce(3+) ions in the CeO2 lattice which favors (5)D0-(7)F1 induced PL properties. As an application of CeO2 NPs towards the degradation of water pollutants, we demonstrated that the Ce1-xEuxO2 (0 ≤x≤ 0.3) NPs can serve as effective photocatalyst materials towards the degradation of the methyl-orange aqueous pollutant dye under UV light irradiation.

8.
J Synchrotron Radiat ; 21(Pt 1): 170-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24365933

RESUMO

Here, an in situ probe for scanning transmission X-ray microscopy (STXM) has been developed and applied to the study of the bipolar resistive switching (BRS) mechanism in an Al/graphene oxide (GO)/Al resistive random access memory (RRAM) device. To perform in situ STXM studies at the C K- and O K-edges, both the RRAM junctions and the I0 junction were fabricated on a single Si3N4 membrane to obtain local XANES spectra at these absorption edges with more delicate I0 normalization. Using this probe combined with the synchrotron-based STXM technique, it was possible to observe unique chemical changes involved in the BRS process of the Al/GO/Al RRAM device. Reversible oxidation and reduction of GO induced by the externally applied bias voltages were observed at the O K-edge XANES feature located at 538.2 eV, which strongly supported the oxygen ion drift model that was recently proposed from ex situ transmission electron microscope studies.


Assuntos
Grafite/química , Microscopia/métodos , Sondas Moleculares , Óxidos/química , Espectroscopia por Absorção de Raios X
9.
J Nutr ; 144(8): 1247-55, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24966409

RESUMO

The consumption of instant noodles is relatively high in Asian populations. It is unclear whether a higher intake of instant noodles is associated with cardiometabolic risk independent of overall dietary patterns. We therefore investigated the association using the Korean National Health and Nutrition Examination Survey IV 2007-2009, a nationally representative cross-sectional survey of the Korean population with a clustered, multistage, stratified, and rolling sampling design. A total of 10,711 adults (54.5% women) 19-64 y of age were analyzed, with adjustment for sampling design complexity. Diet was assessed by using a 63-item food-frequency questionnaire. We identified 2 major dietary patterns with the use of principal components analysis: the "traditional dietary pattern" (TP), rich in rice, fish, vegetables, fruit, and potatoes, and the "meat and fast-food pattern" (MP), with less rice intake but rich in meat, soda, fried food, and fast food including instant noodles. The highest MP quintile was associated with increased prevalence of abdominal obesity (OR: 1.41; 95% CI: 1.05, 1.90), LDL cholesterol ≥130 mg/dL (1.3 g/L) (OR: 1.57, 95% CI 1.26, 1.95), decreased prevalence of low HDL cholesterol (OR: 0.65; 95% CI: 0.53, 0.80), and high triglycerides [≥150 mg/dL (1.5 g/L); OR: 0.73; 95% CI: 0.57, 0.93]. The highest quintile for the TP was associated with decreased prevalence of elevated blood pressure (OR: 0.73; 95% CI: 0.59, 0.90) and marginally lower trends for abdominal obesity (OR: 0.76; 95% CI: 0.58, 0.98; P-trend = 0.06), but neither of the dietary patterns was associated with prevalence of metabolic syndrome. The consumption of instant noodles ≥2 times/wk was associated with a higher prevalence of metabolic syndrome (OR: 1.68; 95% CI: 1.10, 2.55) in women but not in men (OR: 0.93; 95% CI: 0.58, 1.49; P-interaction = 0.04). The 2 major dietary patterns were associated with distinct cardiometabolic risk factors. The consumption of instant noodles was associated with increased prevalence of metabolic syndrome in women, independent of major dietary patterns.


Assuntos
Doenças Cardiovasculares/epidemiologia , Comportamento Alimentar , Síndrome Metabólica/epidemiologia , Obesidade Abdominal/epidemiologia , Adulto , Índice de Massa Corporal , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Transversais , Ingestão de Energia , Feminino , Frutas , Humanos , Masculino , Avaliação Nutricional , Inquéritos Nutricionais , Prevalência , República da Coreia/epidemiologia , Fatores de Risco , Triglicerídeos/sangue , Verduras , Adulto Jovem
10.
Phys Chem Chem Phys ; 16(37): 19909-16, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25116267

RESUMO

Single phase nanoparticles (NPs) of CeO2, Ce0.5Zr0.5O2, Ce0.5Hf0.5O2 and Ce0.5Hf0.25Zr0.25O2 were successfully synthesized by co-precipitation method at constant pH and temperature. The X-ray diffraction results revealed that the additive atoms did not segregate to form secondary phases but led to grain size variation in the NPs. The 10 Dq values in the near edge X-ray absorption fine structure (NEXAFS) spectra at the O K-edge did not vary in the same way as the average grain size was changed for the doped CeO2 NPs. The deconvolution of Ce M5-edge and detailed analysis of O K pre-edge peak have shown the higher Ce(+3)/(Ce(+3) + Ce(+4)) ratio in the Zr- and Hf-doped samples. The local atomic structure around the Ce, Zr and Hf atoms was investigated using extended X-ray absorption fine structure (EXAFS) spectroscopy at Ce K-edge, Zr K-edge and Hf L3-edge, respectively, and the EXAFS data were fitted with the theoretical calculations. The 4f occupancy, Ce(+3)/(Ce(+3) + Ce(+4)) ratio of Ce ions, coordination number of Ce and Ce-Ce/Ce-O bond distances were sensitive to the additive atoms but not explicitly changed according to the grain size variation in the NPs.

11.
Nephron Clin Pract ; 127(1-4): 158-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25343842

RESUMO

High-density lipoprotein cholesterol (HDL-C) contains dozens of apoproteins that participate in normal cholesterol metabolism with a reliance on renal catabolism for clearance from the body. The plasma pool of HDL-C has been an excellent inverse predictor of cardiovascular events. However, when HDL-C concentrations have been manipulated with the use of niacin, fibric acid derivatives, and cholesteryl ester transferase protein inhibitors, there has been no improvement in outcomes in patients where the low-density lipoprotein cholesterol has been well treated with statins. Apolipoprotein L1 (APOL1) is one of the minor apoproteins of HDL-C, newly discovered in 1997. Circulating APOL1 is a 43-kDa protein mainly found in the HDL3 subfraction. In patients with chronic kidney disease (CKD), mutant forms of APOL1 have been associated with rapidly progressive CKD and end-stage renal disease (ESRD). Because mutant forms of APOL1 are more prevalent in African Americans compared to Caucasians, it may explain some of the racial disparities seen in the pool of patients with ESRD in the United States. Thus, HDL-C is an important lipoprotein carrying apoproteins that play roles in vascular and kidney disease.


Assuntos
Apolipoproteína A-I/sangue , HDL-Colesterol/sangue , Cardiopatias/sangue , Nefropatias/sangue , Negro ou Afro-Americano , Amidas , Benzodiazepinas/uso terapêutico , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Proteínas de Transferência de Ésteres de Colesterol/fisiologia , Ésteres do Colesterol/sangue , LDL-Colesterol/sangue , Estudos de Coortes , Ésteres , Humanos , Hiperlipoproteinemias/sangue , Hiperlipoproteinemias/tratamento farmacológico , Fígado/metabolismo , Niacina/uso terapêutico , Estudos Observacionais como Assunto , Oxazolidinonas/uso terapêutico , Estudos Prospectivos , Quinolinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Risco , Compostos de Sulfidrila/uso terapêutico , Triglicerídeos/sangue , População Branca
12.
Angew Chem Int Ed Engl ; 53(5): 1266-9, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24420501

RESUMO

A novel way to grow MoS2 on a large scale with uniformity and in desired patterns is developed. We use Au film as a catalyst on which [Mo(CO)6 ] vapor decomposes to form a Mo-Au surface alloy that is an ideal Mo reservoir for the growth of atomic layers of MoS2 . Upon exposure to H2 S, this surface alloy transforms into a few layers of MoS2 , which can be isolated and transferred on an arbitrary substrate. By simply patterning Au catalyst film by conventional lithographic techniques, MoS2 atomic layers in desired patterns can be fabricated.

13.
Life (Basel) ; 13(10)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37895343

RESUMO

This study aims to activate the external urethral sphincter (EUS), which plays a critical role in micturition control, through optogenetics and to determine its potential contribution to the stabilization of sensitized micturition activity. The viral vector (AAV2/8-CMV-hChR2(H134R)-EGFP) is utilized to introduce light-gated ion channels (hChR2/H134R) into the EUS of wild-type C57BL/6 mice. Following the induction of sensitized micturition activity using weak acetic acid (0.1%) in anesthetized mice, optical stimulation of the EUS muscle tissue expressing channel rhodopsin is performed using a 473 nm laser light delivered through optical fibers, and the resulting changes in muscle activation and micturition activity are examined. Through EMG (electromyography) measurements, it is confirmed that optical stimulation electrically activates the EUS muscle in mice. Analysis of micturition activity using cystometry reveals a 70.58% decrease in the micturition period and a 70.27% decrease in the voiding volume due to sensitized voiding. However, with optical stimulation, the micturition period recovers to 101.49%, and the voiding volume recovered to 100.22%. Stimulation of the EUS using optogenetics can alleviate sensitized micturition activity and holds potential for application in conjunction with other micturition control methods.

14.
Biomed Opt Express ; 14(2): 687-702, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36874485

RESUMO

The development of an accurate subcortical small vessel occlusion model for pathophysiological studies of subcortical ischemic stroke is still insignificant. In this study, in vivo real-time fiber bundle endomicroscopy (FBEµ) was applied to develop subcortical photothrombotic small vessel occlusion model in mice with minimal invasiveness. Our FBFµ system made it possible to precisely target specific blood vessels in deep brain and simultaneously observe the clot formation and blood flow blockage inside the target blood vessel during photochemical reactions. A fiber bundle probe was directly inserted into the anterior pretectal nucleus of the thalamus in brain of live mice to induce a targeted occlusion in small vessels. Then, targeted photothrombosis was performed using a patterned laser, observing the process through the dual-color fluorescence imaging. On day one post occlusion, infarct lesions are measured using TTC staining and post hoc histology. The results show that FBEµ applied to targeted photothrombosis can successfully generate a subcortical small vessel occlusion model for lacunar stroke.

15.
Sci Rep ; 13(1): 22248, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097668

RESUMO

In this report, we present the development of a copper nanofiber network-based microheater, designed for applications in electron microscopes, gas sensing, and cell culture platforms. The seed layer, essential for electroless deposition, was fabricated through the electrospinning of a palladium-contained polyvinylpyrrolidone solution followed by a heat treatment. This process minimized the contact resistance between nanofibers. We successfully fabricated a microheater with evenly distributed temperature by controlling the electrospinning time, heat treatment conditions, and electroless deposition time. We assessed the electrical and thermal characteristics of the microheater by examining the nanofiber density, sheet resistance, and transmittance. The microheater's performance was evaluated by applying current, and we verified its capacity to heat up to a maximum of 350 °C. We further observed the microheater's temperature distribution at varying current levels through an infrared camera. The entire manufacturing procedure takes place under normal pressure, eliminating the need for masking or etching processes. This renders the method easily adaptable to the mass production of microdevices. The method is expected to be applicable to various materials and sizes and is cost-effective compared to commercially produced microheaters developed through microelectromechanical system processes, which demand complex facilities and high cost.

16.
Nano Lett ; 11(6): 2472-7, 2011 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-21595452

RESUMO

Although various carbon nanomaterials including activated carbon, carbon nanotubes, and graphene have been successfully demonstrated for high-performance ultracapacitors, their capacitances need to be improved further for wider and more challenging applications. Herein, using nitrogen-doped graphene produced by a simple plasma process, we developed ultracapacitors whose capacitances (∼280 F/g(electrode)) are about 4 times larger than those of pristine graphene based counterparts without sacrificing other essential and useful properties for ultracapacitor operations including excellent cycle life (>200,000), high power capability, and compatibility with flexible substrates. While we were trying to understand the improved capacitance using scanning photoemission microscopy with a capability of probing local nitrogen-carbon bonding configurations within a single sheet of graphene, we observed interesting microscopic features of N-configurations: N-doped sites even at basal planes, distinctive distributions of N-configurations between edges and basal planes, and their distinctive evolutions with plasma duration. The local N-configuration mappings during plasma treatment, alongside binding energy calculated by density functional theory, revealed that the origin of the improved capacitance is a certain N-configuration at basal planes.


Assuntos
Grafite/química , Nitrogênio/química , Tamanho da Partícula , Propriedades de Superfície
17.
Ann Palliat Med ; 11(7): 2285-2290, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35400155

RESUMO

BACKGROUND: A recent systematic review and meta-analysis reporting on thirteen published cohorts investigating 110,078 patients demonstrated that patients who were administered statins after their COVID-19 diagnosis and hospitalization were had a lower risk of mortality. While these findings are encouraging, given competing COVID-19 treatment approaches, it is unclear if statin use should be prioritized and if its use is a cost-effective treatment options for hospitalized COVID-19 patients. In this study, we report on a cost-effectiveness analysis of statin-containing treatment regimens for hospitalized COVID-19 patients. METHODS: A Markov model was used to compare statin use and no statin use among hospitalized COVID-19 patients from a United States healthcare perspective. The cycle length was one week, with a time horizon of 4 weeks. A Monte Carlo microsimulation with 20,000 samples were used. All analyses were conducted using TreeAge Pro Healthcare Version 2021 R1.1. RESULTS: The mean cost for patients receiving statins in addition to usual care was $31,623 (SD $20,331), whereas the mean cost for patients not receiving statins was $33,218 (SD $25,440). The mean effectiveness for the two cohorts were 1.73 (SD 0.96) and 1.71 (SD 1.00), respectively. CONCLUSIONS: This analysis demonstrated that treatment of hospitalized COVID-19 patients with statins was both cheaper and more effective than treatment without statins; statin-containing therapy dominates over non-statin therapy. Statin medications for the treatment of COVID-19 should be further investigated in randomized controlled trials, especially considering its cost-effective nature. Optimistically and pending the results of future randomized trials, statins should be considered for use broadly for the treatment of hospitalized COVID-19 patients.


Assuntos
Tratamento Farmacológico da COVID-19 , Inibidores de Hidroximetilglutaril-CoA Redutases , Teste para COVID-19 , Análise Custo-Benefício , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Estados Unidos
18.
Sci Rep ; 12(1): 21052, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36473950

RESUMO

Full-night polysomnography (PSG) is the gold standard for diagnosing obstructive sleep apnea (OSA). However, PSG requires several sensors to be attached to the patient's body, which can interfere with sleep. Moreover, non-contact devices that utilize impulse radio ultra-wideband radar have limitations as they cannot directly measure respiratory airflow. This study aimed to detect respiratory events through infrared optical gas imaging and verify its feasibility for the diagnosis of OSA. Data collection through PSG and infrared optical gas imaging was simultaneously conducted on 50 volunteers. Respiratory airflow signal was extracted from the infrared optical gas images using an automated algorithm. We compared the respiratory parameters obtained from infrared optical gas imaging with those from PSG. All respiratory events scored from the infrared optical gas imaging were strongly correlated with those identified with standard PSG sensors. Based on a receiver operating characteristic curve, infrared optical gas imaging was deemed appropriate for the diagnosis of OSA. Infrared optical gas imaging accurately detected respiratory events during sleep; therefore, it may be employed as a screening tool for OSA.


Assuntos
Sono , Humanos
19.
Ann Palliat Med ; 11(4): 1308-1316, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35445604

RESUMO

BACKGROUND: There is uncertainty of the effect of immunosuppression, including corticosteroids, before COVID-19 infection on COVID-19 outcomes. The aim of this study was to investigate the relationship between prehospitalization immunosuppressants use (exposure) and COVID-19 patient outcomes. METHODS: We conducted a population-based retrospective cohort study using a nationwide healthcare claims database of South Korea as of May 15, 2020. Confirmed COVID-19 infection in hospitalized individuals aged 40 years or older were included for analysis. We defined exposure variable by using inpatient and outpatient prescription records of immunosuppressants from the database. Our primary endpoint was a composite endpoint of all-cause death, intensive care unit (ICU) admission, and mechanical ventilation use. Inverse probability of treatment weighting (IPTW)-adjusted logistic regression analyses were used, to estimate odds ratio (OR) and 95% confidence intervals (CI), comparing immunosuppressants users and non-users. RESULTS: We identified 4,349 patients, for which 1,356 were immunosuppressants users and 2,993 were non-users. Patients who used immunosuppressants were at increased odds of the primary endpoint of all-cause death, ICU admission and mechanical ventilation use (IPTW OR =1.32; 95% CI: 1.06-1.63), driven by higher odds of all-cause mortality (IPTW OR =1.63; 95% CI: 1.21-2.26). Patients who used corticosteroids (n=1,340) were at increased odds of the primary endpoint (IPTW OR =1.33; 95% CI: 1.07-1.64). CONCLUSIONS: Immunosuppressant use was associated with worse outcomes among COVID-19 patients. These findings support the latest guidelines from the CDC that people on immunosuppressants are at high risk of severe COVID-19 and that immunocompromised people may benefit from booster COVID-19 vaccinations.


Assuntos
COVID-19 , Estudos de Coortes , Hospitalização , Humanos , Imunossupressores/efeitos adversos , Unidades de Terapia Intensiva , Estudos Retrospectivos
20.
Ann Palliat Med ; 11(4): 1317-1325, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35400157

RESUMO

BACKGROUND: There currently exists a paucity of data on whether pre-admission anticoagulants use may have benefits among COVID-19 patients by preventing COVID-19 associated thromboembolism. The aim of this study was to assess the association between pre-admission anticoagulants use and COVID-19 adverse outcomes. METHODS: We conducted a population-based cohort studying using the Health Insurance Review and Assessment Service (HIRA) claims data released by the South Korean government. Our study population consisted of South Koreans who were aged 40 years or older and hospitalized with COVID-19 between 1 January 2020 through 15 May 2020. We defined anticoagulants users as individuals with inpatient and outpatient prescription records in 120 days before cohort entry. Our primary endpoint was a composite of all-cause death, intensive care unit (ICU) admission, and mechanical ventilation use. Individual components of the primary endpoint were secondary endpoints. We compared the risk of endpoints between the anticoagulants users and non-users by logistic regression models, with the standardized mortality ratio weighting (SMRW) adjustment. RESULTS: In our cohort of 4,349 patients, for the primary endpoint of mortality, mechanical ventilation and ICU admission, no difference was noted between anticoagulants users and non-users (SMRW OR 1.11, 95% CI: 0.60-2.05). No differences were noted, among individual components. No effect modification was observed by age, sex, history of atrial fibrillation and thromboembolism, and history of cardiovascular disease. When applying the inverse probability of treatment weighting (IPTW) and SMRW with doubly robust methods in sensitivity analysis, anticoagulants use was associated with increased odds of the primary endpoint. CONCLUSIONS: Pre-admission anticoagulants were not determined to have a protective role against severe COVID-19 outcomes.


Assuntos
COVID-19 , Tromboembolia , Anticoagulantes/uso terapêutico , Humanos , Prognóstico , SARS-CoV-2 , Tromboembolia/induzido quimicamente
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA