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1.
Nature ; 620(7975): 768-775, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37612392

RESUMO

Models of artificial intelligence (AI) that have billions of parameters can achieve high accuracy across a range of tasks1,2, but they exacerbate the poor energy efficiency of conventional general-purpose processors, such as graphics processing units or central processing units. Analog in-memory computing (analog-AI)3-7 can provide better energy efficiency by performing matrix-vector multiplications in parallel on 'memory tiles'. However, analog-AI has yet to demonstrate software-equivalent (SWeq) accuracy on models that require many such tiles and efficient communication of neural-network activations between the tiles. Here we present an analog-AI chip that combines 35 million phase-change memory devices across 34 tiles, massively parallel inter-tile communication and analog, low-power peripheral circuitry that can achieve up to 12.4 tera-operations per second per watt (TOPS/W) chip-sustained performance. We demonstrate fully end-to-end SWeq accuracy for a small keyword-spotting network and near-SWeq accuracy on the much larger MLPerf8 recurrent neural-network transducer (RNNT), with more than 45 million weights mapped onto more than 140 million phase-change memory devices across five chips.

3.
Scand J Rheumatol ; 51(6): 500-505, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35638589

RESUMO

OBJECTIVE: Nucleic acid-based vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection are effective in the general population. However, it is unknown whether this is true in Asian patients with autoimmune rheumatic diseases (ARDs) who have received various combinations of disease-modifying anti-rheumatic drugs (DMARDs). METHOD: We designed a large prospective observational study recruiting 228 patients with ARDs in a tertiary rheumatology centre in Taiwan. Altogether, 142 received biological or targeted synthetic DMARDs and 86 received only conventional synthetic (cs) DMARDs. Serum levels of immunoglobulin G antibody against SARS-CoV-2 spike proteins were measured 2-6 weeks after COVID-19 vaccination with mRNA-1273 (Moderna®) or ChAdOx1 nCoV-19 (Oxford/AstraZeneca®). The immunomodulatory therapies were not modified before or after vaccination. RESULTS: Overall, 194 patients (85.09%) exhibited antibodies (758.33 ± 808.43 ng/mL) but 34 patients did not (103.24 ± 41.08 ng/mL). Patients with systemic lupus erythematosus or rheumatoid arthritis had significantly lower humoral responses to COVID-19 vaccination than those with other ARDs (p < 0.05). There was no significant difference in immunogenicity among patients on different csDMARD treatments. Compared to patients treated with only csDMARDs, those on rituximab or abatacept therapy had significantly lower immune response to the vaccination (p = 0.008 and p = 0.035, respectively). Patients who were treated with anti-tumour necrosis factor-α or interleukin-6 inhibitor exhibited higher titres of vaccination antibodies than those treated with direct lymphocyte inhibitors. CONCLUSIONS: mRNA-1273 and ChAdOx1 nCoV-19 vaccines were immunogenic in the majority of ARD patients. Rituximab and abatacept were associated with significantly diminished COVID-19 vaccination immunogenicity.


Assuntos
Antirreumáticos , Artrite Reumatoide , Doenças Autoimunes , COVID-19 , Síndrome do Desconforto Respiratório , Doenças Reumáticas , Humanos , SARS-CoV-2 , Vacinas contra COVID-19/uso terapêutico , ChAdOx1 nCoV-19 , Vacina de mRNA-1273 contra 2019-nCoV , COVID-19/prevenção & controle , Abatacepte/uso terapêutico , Imunossupressores/uso terapêutico , Rituximab/uso terapêutico , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/induzido quimicamente , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Vacinação , Anticorpos Antivirais , Doenças Reumáticas/tratamento farmacológico
4.
Eur Rev Med Pharmacol Sci ; 25(23): 7543-7552, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34919256

RESUMO

OBJECTIVE: We analyzed real-world data to elucidate the effects of anti-Hepatitis C virus (HCV) direct-acting antiviral (DAA) therapy on survival in patients with advanced hepatocellular carcinoma (HCC) and concomitant HCV infection treated with sorafenib. MATERIALS AND METHODS: This population-based retrospective cohort study used the Taiwan National Health Insurance Research Database and the Registration System for Patients Treated with Oral Hepatitis C Antivirals to identify patients with advanced HCC and concomitant HCV infection who received initial targeted therapy (sorafenib) in 2018-2019. The overall survival (OS) of the DAA and non-DAA groups were compared using the Kaplan-Meier survival analysis. Propensity score matching was performed using a ratio of 1:4 to reduce confounding between the DAA and non-DAA groups. RESULTS: The study included 1,684 patients (122 DAA and 1,562 non-DAA users) with HCC and concomitant HCV infection who used sorafenib for the first time in 2018-2019. The Kaplan-Meier survival analysis indicated that advanced HCC patients who used DAAs had longer OS compared to non-DAA patients. The mean survival times were 20.7 months for DAA and 12.5 months for non-DAA. Results obtained after propensity matching indicated a significant difference in OS between the DAA and non-DAA groups. CONCLUSIONS: The analysis of big data from the Taiwan National Health Insurance Research Database revealed that advanced HCC patients on sorafenib benefited from DAAs as a treatment for HCV infection. Patients whose HCV infection was cured had better OS.


Assuntos
Antivirais/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Idoso , Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sorafenibe/administração & dosagem , Taxa de Sobrevida , Resultado do Tratamento
5.
J Instrum ; 16(3)2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33868448

RESUMO

Precise quantitative delineation of tumor hypoxia is essential in radiation therapy treatment planning to improve the treatment efficacy by targeting hypoxic sub-volumes. We developed a combined imaging system of positron emission tomography (PET) and electron para-magnetic resonance imaging (EPRI) of molecular oxygen to investigate the accuracy of PET imaging in assessing tumor hypoxia. The PET/EPRI combined imaging system aims to use EPRI to precisely measure the oxygen partial pressure in tissues. This will evaluate the validity of PET hypoxic tumor imaging by (near) simultaneously acquired EPRI as ground truth. The combined imaging system was constructed by integrating a small animal PET scanner (inner ring diameter 62 mm and axial field of view 25.6 mm) and an EPRI subsystem (field strength 25 mT and resonant frequency 700 MHz). The compatibility between the PET and EPRI subsystems were tested with both phantom and animal imaging. Hypoxic imaging on a tumor mouse model using 18F-fluoromisonidazole radio-tracer was conducted with the developed PET/EPRI system. We report the development and initial imaging results obtained from the PET/EPRI combined imaging system.

6.
BJOG ; 128(9): 1497-1502, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33629515

RESUMO

OBJECTIVE: To investigate whether antenatal corticosteroid therapy improves neonatal and maternal outcomes in late preterm delivery. DESIGN: Population-based retrospective study. SETTING: The linkages of Taiwan's National Health Insurance Research Database, National Birth Reporting Database, and the Taiwan Maternal and Child Health Database. POPULATION: All births at risk for late preterm deliveries in Taiwan between 2004 and 2011. METHODS: For every birth at risk for late preterm delivery, five controls randomly matched by maternal and gestational ages and birthweight were included. A conditional logistic regression analysis was applied for risk estimation, with births without corticosteroids as the reference group. Odds ratios were adjusted for caesarean section, parity, sex, gestational hypertension and gestational diabetes mellitus. MAIN OUTCOME MEASURES: Neonatal outcomes, maternal outcomes and the utilisation of healthcare services. RESULTS: The outcomes of 5745 women treated with corticosteroids between 34+0  weeks and 36+6  weeks of gestation were compared with those of 28 135 untreated controls. Compared with the controls, births from women administered corticosteroids reduced the need for continuous positive airway pressure, the number of neonatal intensive care unit admission, and the need for glucose administration, as well as the risk of neonatal respiratory distress, but increased the risk of neonatal sepsis and the number of outpatient visits. CONCLUSIONS: Antenatal corticosteroid therapy in women at risk of late preterm delivery may significantly reduce the need for respiratory support and glucose supply, and respiratory complication risk in neonates. TWEETABLE ABSTRACT: Antenatal corticosteroids in late preterm delivery reduced the risk of neonatal respiratory complications in Taiwan.


Assuntos
Corticosteroides/administração & dosagem , Nascimento Prematuro/tratamento farmacológico , Síndrome do Desconforto Respiratório do Recém-Nascido/prevenção & controle , Corticosteroides/efeitos adversos , Adulto , Estudos de Casos e Controles , Bases de Dados Factuais , Feminino , Humanos , Recém-Nascido , Masculino , Sepse Neonatal/epidemiologia , Gravidez , Nascimento Prematuro/epidemiologia , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Estudos Retrospectivos , Medição de Risco , Taiwan/epidemiologia
7.
J Endocrinol Invest ; 44(4): 755-763, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32729050

RESUMO

PURPOSE: Primary hyperparathyroidism has deleterious effects on health and causes nephrolithiasis and osteoporosis. However, it remains unclear whether parathyroidectomy benefits kidney function among patients with primary hyperparathyroidism. METHODS: In this retrospective study, patients with primary hyperparathyroidism receiving parathyroidectomy in a tertiary medical center between 2003 and 2017 were followed up until December 31 2017, death, or requiring renal replacement therapy. Impact of parathyroidectomy on kidney function was examined using longitudinal estimated glomerular filtration rate (eGFR) change scales: single, average, absolute difference, percent change, annual decline rate, and slope. We applied linear mixed-effect model to determine the effect of parathyroidectomy on kidney function. RESULTS: During study period, 167 patients with primary hyperparathyroidism were identified from 498 parathyroidectomized patients, and finally, 27 patients fulfilled our stringent criteria. Median follow-up duration was 1.50 years (interquartile range 1.05-1.81) before surgery and 2.47 years (1.37-6.43) after surgery. Although parathyroidectomy did not affect amount of proteinuria and distribution of eGFR, parathyroidectomy significantly slowed decline rate of eGFR compared with that before surgery (- 1.67 versus - 2.73 mL/min/1.73 m2/year, p < 0.001). More importantly, parathyroidectomy made more beneficial effects on kidney function in patients with age < 65 years and those without chronic kidney disease or hypertension. CONCLUSIONS: Our study showed that parathyroidectomy slows renal function decline irrespective of age or comorbidities, which offers novel insight into the revision of guidelines for surgical indications in primary hyperparathyroidism. Given small sample size, further large-scale controlled studies are warranted to confirm our findings.


Assuntos
Hiperparatireoidismo Primário , Testes de Função Renal , Paratireoidectomia , Insuficiência Renal , Prevenção Secundária/métodos , Fatores Etários , China/epidemiologia , Feminino , Taxa de Filtração Glomerular , Humanos , Hiperparatireoidismo Primário/complicações , Hiperparatireoidismo Primário/epidemiologia , Hiperparatireoidismo Primário/cirurgia , Testes de Função Renal/métodos , Testes de Função Renal/estatística & dados numéricos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Paratireoidectomia/métodos , Paratireoidectomia/estatística & dados numéricos , Período Pós-Operatório , Proteinúria/diagnóstico , Proteinúria/etiologia , Insuficiência Renal/diagnóstico , Insuficiência Renal/etiologia , Insuficiência Renal/prevenção & controle , Terapia de Substituição Renal/estatística & dados numéricos
8.
Sci Rep ; 10(1): 7712, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32382098

RESUMO

The annotation of short-reads metagenomes is an essential process to understand the functional potential of sequenced microbial communities. Annotation techniques based solely on the identification of local matches tend to confound local sequence similarity and overall protein homology and thus don't mirror the complex multidomain architecture and the shuffling of functional domains in many protein families. Here, we present MetaGeneHunt to identify specific protein domains and to normalize the hit-counts based on the domain length. We used MetaGeneHunt to investigate the potential for carbohydrate processing in the mouse gastrointestinal tract. We sampled, sequenced, and analyzed the microbial communities associated with the bolus in the stomach, intestine, cecum, and colon of five captive mice. Focusing on Glycoside Hydrolases (GHs) we found that, across samples, 58.3% of the 4,726,023 short-read sequences matching with a GH domain-containing protein were located outside the domain of interest. Next, before comparing the samples, the counts of localized hits matching the domains of interest were normalized to account for the corresponding domain length. Microbial communities in the intestine and cecum displayed characteristic GH profiles matching distinct microbial assemblages. Conversely, the stomach and colon were associated with structurally and functionally more diverse and variable microbial communities. Across samples, despite fluctuations, changes in the functional potential for carbohydrate processing correlated with changes in community composition. Overall MetaGeneHunt is a new way to quickly and precisely identify discrete protein domains in sequenced metagenomes processed with MG-RAST. In addition, using the sister program "GeneHunt" to create custom Reference Annotation Table, MetaGeneHunt provides an unprecedented way to (re)investigate the precise distribution of any protein domain in short-reads metagenomes.


Assuntos
Bactérias/genética , Metagenoma/genética , Domínios Proteicos/genética , Software , Animais , Biologia Computacional , Bases de Dados Genéticas , Genoma Microbiano/genética , Metagenômica/métodos , Camundongos , Microbiota/genética , Anotação de Sequência Molecular , Análise de Sequência
9.
Artigo em Inglês | MEDLINE | ID: mdl-33612902

RESUMO

We present the development of a PET insert system for potential simultaneous PET/MR imaging using a 9.4 T small animal MRI scanner to test our system. The detectors of the system adopt a strip-line based multiplexing readout method for SiPM signals. In this readout, multiple SiPM outputs in a row share a common strip-line. The position information about a hit SiPM is encoded in the propagation time difference of the signals arriving at the two ends of the strip-line. The use of strip-lines allows us to place the data acquisition electronics remotely from the detector module to greatly simplify the design of the detector module and minimize the mutual electromagnetic interference. The prototype is comprised of 14 detector modules, each of which consists of an 8x4 LYSO scintillator array (each LYSO crystal is 3x3x10 mm3) coupled to two units of Hamamatsu MPPC arrays (4x4, 3.2 mm pitch) that are mounted on a strip-line board. On the strip-line board, outputs of the 32 SiPMs are routed to 2 strip-lines so that 16 SiPM signals share a strip-line. The detector modules are installed inside a plastic cylindrical supporting structure with an inner and outer diameter of 60 mm and 115 mm, respectively, to fit inside a Bruker BioSpec 9.4 Tesla MR scanner. The axial field of view of the prototype is 25.4 mm. The strip-lines were extended by using 5-meter cables to a sampling data acquisition (DAQ) board placed outside the magnet. The detectors were not shielded in the interest of investigating how they may affect and be affected by the MRI. Experimental tests were conducted to evaluate detection performance, and phantom and animal imaging were carried out to assess the spatial resolution and the MR compatibility of the PET insert. Initial results are encouraging and demonstrate that the prototype insert PET can potentially be used for PET/MR imaging if appropriate shielding will be implemented for minimizing the mutual interference between the PET and MRI systems.

11.
Sci Rep ; 9(1): 18586, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31819082

RESUMO

Temperature-dependent X-ray absorption near-edge structures, X-ray linear dichroism (XLD) and extended X-ray absorption fine structure (EXAFS) spectroscopic techniques were used to investigate the valence state, preferred orbital and local atomic structure that significantly affect the electrical and magnetic properties of a single crystal of YBaCuFeO5 (YBCFO). An onset of increase of resistivity at ~180 K, followed by a rapid increase at/below 125 K, is observed. An antiferromagnetic (AFM)-like transition is close to the temperature at which the resistivity starts to increase in the ab-plane and is also observed with strong anisotropy between the ab-plane and the c-axis. The XLD spectra at the Fe L3,2-edge revealed a change in Fe 3d eg holes from the preferential [Formula: see text] orbital at high temperature (300-150 K) to the [Formula: see text] orbital at/below 125 K. The analysis of the Fe K-edge EXAFS data of YBCFO further revealed an unusual increase in the Debye-Waller factor of the nearest-neighbor Fe-O bond length at/below 125 K, suggesting phonon-softening behavior, resulting in the breaking of lattice symmetry, particularly in the ab-plane of Fe-related square pyramids. These findings demonstrate a close correlation between electrical resistivity and coupling of the preferred Fe 3d orbital with lattice distortion of a single crystal of YBCFO.

12.
Nanotechnology ; 30(50): 505101, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31557130

RESUMO

This study reports the online fluorescent detection of carcinoembryonic antigen (CEA) and α-fetoprotein (AFP) biomarker proteins in microfluidic channels using functional nanoparticles. Functional magnetic nanoparticles labeled with two antibodies were predeposited on separated microfluidic channels. Antigens were passed through each microfluidic channel to react with the respective antibodies. Two types of fluorescent nanoparticles labeled with antibodies were then used to detect and confirm antigens in the immunocomplex. Results indicate that online fluorescent detection of proteins can provide advantages for real-time monitoring and diagnostic applications. The running time was less than 20 min for each trial. The detection limits of CEA and AFP were found to be 0.6 and 0.2 pg ml-1. These detection limits are lower than those of ELISA. The linear ranges of CEA and AFP detection were from 1.8 pg ml-1 to 1.8 ng ml-1 and from 0.68 pg ml-1 to 0.68 ng ml-1 for two deposition zones in a magnetic sandwich immunoassay. The linear ranges of this method are wider than those of ELISA and those of most other methods. The measurements of CEA and AFP in serum samples from this method differed from ELISA results by 11% and 9.4%, respectively. The detection limit of online detection has achieved the same range as those of previous offline detection. This method has a good potential for automation and multichannel analysis to increase the throughput with some modifications in the future. The proposed method can provide simple, fast, and sensitive online detection for biomarkers.

14.
Mucosal Immunol ; 12(4): 980-989, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31076664

RESUMO

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces cell apoptosis by transducing apoptosis signals. Recently, accumulating evidence demonstrated that TRAIL regulates autoimmune inflammation and immune cell homeostasis in several autoimmune animal models, suggesting a novel immunoregulatory role of TRAIL in autoimmune diseases. However, the impact of TRAIL in inflammatory bowel disease is yet undefined. This study is to address the therapeutic effects and immunoregulatory role of TRAIL in autoimmune gut inflammation. We demonstrated herein that TRAIL significantly suppressed gut inflammation and reduced the severity of colitis in a dextran sodium sulfate (DSS)-induced colitis model. Suppression of gut inflammation was not due to induction of apoptosis in colonic T cells, dendritic cells, or epithelium cells by TRAIL. In contrast, TRAIL directly inhibited activation of colitogenic T cells and development of gut inflammation in an adoptive transfer-induced colitis model. The anti-inflammatory effects of TRAIL on colitis were abolished when T cells from TRAIL receptor (TRAIL-R) knockout mice were adoptively transferred, suggesting that TRAIL regulates autoreactive colitogenic T-cell activation in the development of gut inflammation. Our results demonstrate that TRAIL effectively inhibited colonic T-cell activation and suppressed autoimmune colitis, suggesting a potential therapeutic application of TRAIL in human inflammatory bowel disease.


Assuntos
Colite/etiologia , Colite/metabolismo , Ativação Linfocitária/imunologia , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Animais , Apoptose , Autoimunidade , Colite/patologia , Citocinas/metabolismo , Sulfato de Dextrana , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Knockout
15.
Sci Rep ; 9(1): 5160, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30914713

RESUMO

This study probes the temperature-dependent strain that is strongly correlated with the orbital and magnetic structures of epitaxial films of Nd0.35Sr0.65MnO3 (NSMO) that are fabricated by pulsed laser deposition with two thicknesses, 17 (NS17) and 103 nm (NS103) on SrTiO3 (STO) substrate. This investigation is probed using X-ray diffraction (XRD) and absorption-based techniques, X-ray linear dichroism (XLD) and the X-ray magnetic circular dichroism (XMCD). XRD indicates a significant shift in the (004) peak position that is associated with larger strain in NS17 relative to that of NS103 at both 30 and 300 K. Experimental and atomic multiplet simulated temperature-dependent Mn L3,2-edge XLD results reveal that the stronger strain in a thinner NS17 film causes less splitting of Mn 3d eg state at low temperature, indicating an enhancement of orbital fluctuations in the band above the Fermi level. This greater Mn 3d orbital fluctuation can be the cause of both the enhanced ferromagnetism (FM) as a result of spin moments and the reduced Néel temperature of C-type antiferromagnetism (AFM) in NS17, leading to the FM coupling of the canted-antiferromagnetism (FM-cAFM) state in NSMO/STO epitaxial films at low temperature (T = 30 K). These findings are also confirmed by Mn L3,2-edge XMCD measurements.

16.
Transplant Proc ; 50(9): 2733-2737, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401386

RESUMO

BACKGROUND: The ventilatory efficiency represented cardiovascular, pulmonary, and musculoskeletal performance into an integrate index has been used as long-term and short-term prognostic variables in congestive heart failure. The heart failure patients post heart transplantation, whether the ventilatory efficiency was also normalized is still unknown. METHODS: This was a cross-sectional study. We measured ventilation to carbon dioxide production slope and oxygen consumption in peak exercise (peak VO2) by cardiopulmonary exercise test, which represented ventilatory efficiency and functional capacity respectively. Strength of hand grip, the 30-second chair stand test, and 6-minute walking test were also evaluated. Patients with ventilation to carbon dioxide production slope <30 were defined as the normal group; others were defined as the abnormal group. Independent t tests and paired t tests were used when appropriate. The level of statistical significance was set at .05. RESULTS: There were 51 clinically stable post-heart transplantation patients (age 53 ± 12.4 years; 86.3% were male) at 65.14 ± 41.17 months after transplantation. The ventilation to carbon dioxide production slope was 29.2 ± 5.6, which significantly improved compared to that recorded 1 month after heart transplantation (32.6 ± 6.4). There were 20 patients in the abnormal group, characterized by lower 6-minute walking test distance (normal vs abnormal, 422.5 ± 97.8 vs 532.6 ± 87.6 m) and peak VO2 (normal vs abnormal, 14.9 ± 5.3 vs 18.8 ± 5.1 mL/kg/min). The abnormal ventilation to carbon dioxide production slope was significantly correlated with 6-minute walking test distances in multivariate analyses. CONCLUSION: Our findings indicate that the ventilation to carbon dioxide production slope is partially abnormal among patients post-heart transplantation. A ventilation to carbon dioxide production slope above the normal range is characterized by a lower peak VO2 during cardiopulmonary exercise test and lower 6-minute walking test distance. The ventilation to carbon dioxide production slope is also significantly negatively correlated with peak VO2, peak work rate, and 6-minute walking test distance. The prognostic utility of the ventilation to carbon dioxide production slope for patients post-heart transplantation requires further investigation.


Assuntos
Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Transplante de Coração , Ventilação Pulmonar/fisiologia , Idoso , Estudos Transversais , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Consumo de Oxigênio , Prognóstico , Testes de Função Respiratória
17.
Transplant Proc ; 50(9): 2742-2746, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401388

RESUMO

OBJECTIVES: The ventilatory efficiency and functional capacity measured by the cardiopulmonary exercise test (CPET) have been used as important prognostic variables in congestive heart failure. This study sought to identify whether these predictors before heart transplantation (HTX) play a key role in predicting adverse events in patients with heart failure after HTX. METHODS: This was a retrospective cohort study design. HTX recipients were included for analysis. Ventilation to carbon dioxide production slope (VE/VCO2 slope) and oxygen consumption (VO2) during exercise were collected by CPET, which represented ventilator efficiency and functional capacity respectively. Cardiac-related events 2 years after HTX were recorded by chart review. We divided patients into 2 groups based on VE/VCO2 slope = 34, peak VO2 = 14 mL/kg/min and VO2 at aerobic threshold (AT) = 11 mL/kg/min. Kaplan-Meier survival curves was used to represent the events rate between groups and Log rank test was used to test significance. RESULTS: A total of 87 patients after HTX were included. Mean (SD) age was 48 (11) years and 73 were male; 28 subjects suffered from events, and 76 cardiac events were recorded. The mean (SD) data of peak VO2, VO2 at AT, and VE/VCO2 slope analyzed from CPET were 17.8 (5.6) mL/kg/min, 15.4 (4.4) mL/kg/min, and 33.1 (8.2) mL/kg/min, respectively. Lower VO2 at AT contributed to increase events rate (P < .05). CONCLUSION: Aerobic capacity may better predict 2-year cardiac events in patients after HTX. Strategies to improve aerobic capacity should be focused on in the cohort.


Assuntos
Limiar Anaeróbio/fisiologia , Insuficiência Cardíaca/fisiopatologia , Transplante de Coração/efeitos adversos , Adulto , Idoso , Estudos de Coortes , Teste de Esforço , Tolerância ao Exercício/fisiologia , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Transplante de Coração/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
18.
Sci Rep ; 8(1): 15779, 2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-30361523

RESUMO

This investigation reports on anisotropy in the magnetic interaction, lattice-orbital coupling and degree of phonon softening in single crystal Ni3TeO6 (NTO) using temperature- and polarization-dependent X-ray absorption spectroscopic techniques. The magnetic field-cooled and zero-field-cooled measurements and temperature-dependent Ni L3,2-edge X-ray magnetic circular dichroism spectra of NTO reveal a weak Ni-Ni ferromagnetic interaction close to ~60 K (TSO: temperature of the onset of spin ordering) with a net alignment of Ni spins (the uncompensated components of the Ni moments) along the crystallographic c-axis, which is absent from the ab-plane. Below the Néel temperature, TN~ 52 K, NTO is stable in the antiferromagnetic state with its spin axis parallel to the c-axis. The Ni L3,2-edge X-ray linear dichroism results indicate that above TSO, the Ni 3d eg electrons preferentially occupy the out-of-plane 3d3z2-r2 orbitals and switch to the in-plane 3dx2-y2 orbitals below TSO. The inherent distortion of the NiO6 octahedra and anisotropic nearest-neighbor Ni-O bond lengths between the c-axis and the ab-plane of NTO, followed by anomalous Debye-Waller factors and orbital-lattice in conjunction with spin-phonon couplings, stabilize the occupied out-of-plane (3d3z2-r2) and in-plane (3dx2-y2) Ni eg orbitals above and below TSO, respectively.

19.
Nat Commun ; 9(1): 2254, 2018 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-29884900

RESUMO

Ruddlesden-Popper halide perovskites are 2D solution-processed quantum wells with a general formula A2A'n-1M n X3n+1, where optoelectronic properties can be tuned by varying the perovskite layer thickness (n-value), and have recently emerged as efficient semiconductors with technologically relevant stability. However, fundamental questions concerning the nature of optical resonances (excitons or free carriers) and the exciton reduced mass, and their scaling with quantum well thickness, which are critical for designing efficient optoelectronic devices, remain unresolved. Here, using optical spectroscopy and 60-Tesla magneto-absorption supported by modeling, we unambiguously demonstrate that the optical resonances arise from tightly bound excitons with both exciton reduced masses and binding energies decreasing, respectively, from 0.221 m0 to 0.186 m0 and from 470 meV to 125 meV with increasing thickness from n equals 1 to 5. Based on this study we propose a general scaling law to determine the binding energy of excitons in perovskite quantum wells of any layer thickness.

20.
J Postgrad Med ; 64(3): 155-163, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29848836

RESUMO

Background: Perioperative enteral nutrition (EN) enriched with immune-modulating substrates is preferable for patients undergoing major abdominal cancer surgery. In this study, perioperative EN enriched with immune-modulating nutrients such as arginine, glutamine, and omega-3 fatty acids was evaluated for its anti-inflammatory efficacy in patients with gastric adenocarcinoma or gastrointestinal stromal tumor (GIST) receiving curative surgery. Materials and Methods: This prospective, randomized, double-blind study recruited 34 patients with gastric adenocarcinoma or gastric GIST undergoing elective curative surgery. These patients were randomly assigned to the study group, receiving immune-modulating nutrient-enriched EN, or the control group, receiving standard EN from 3 days before surgery (preoperative day 3) to up to postoperative day 14 or discharge. Laboratory and inflammatory parameters were assessed on preoperative day 3 and postoperative day 14 or at discharge. Adverse events (AEs) and clinical outcomes were documented daily and compared between groups. Results: No significant differences were observed between the two groups in selected laboratory and inflammatory parameters, or in their net change, before and after treatment. AEs and clinical outcomes, including infectious complications, overall complications, time to first bowel action, and length of hospital stay after surgery, were comparable between treatment groups (all P > 0.05). Conclusion: Immune-modulating nutrient-enriched EN had no prominent immunomodulation effect compared with that of standard EN.


Assuntos
Adenocarcinoma/terapia , Arginina/administração & dosagem , Nutrição Enteral/métodos , Ácidos Graxos Ômega-3/administração & dosagem , Tumores do Estroma Gastrointestinal/terapia , Glutamina/administração & dosagem , Neoplasias Gástricas/terapia , Idoso , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória/métodos , Estudos Prospectivos , Resultado do Tratamento
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