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1.
Biosens Bioelectron ; 147: 111787, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655381

RESUMO

Exosome released from cells plays an important role in intercellular communication and show great clinical potential in early cancer screening and prognosis. Herein, an ultrasensitive Giant Magnetoresistance (GMR) biosensor was developed for exosome detection, which was based on 2D MoS2-Fe3O4 nanostructures (MOFE) as magnetic responsive probes for signal amplification. The MOFE can be readily synthesized with simple phase transfer method. Compared to pure Fe3O4 magnetic nanoparticles (MNPs), the layered MoS2 function as a template for recruiting high loading density of MNPs as magnetic probes. After modified by aptamer, we discover that the 2D magnetic MOFE hybrid nanostructures enable both multidentate targeting and multi-magnetic particle-based signal amplification, increasing the magnetic sensor performance, especially in sensitivity and output signal. Moreover, the 2D magnetic nanocomposites afford high selectivity and excellent reproducibility with detection limit of 100 exosomes in GMR sensor. Results demonstrate that the magnetic strategy based on 2D structures introduced here provide a new dimension for exosome detection, which show great potential of engineering 2D magnetic nanobioprobes for GMR based liquid biopsy application.

2.
J Exp Clin Cancer Res ; 38(1): 438, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666108

RESUMO

BACKGROUND: Glutathione S-transferase zeta 1 (GSTZ1) is the penultimate enzyme in phenylalanine/tyrosine catabolism. GSTZ1 is dysregulated in cancers; however, its role in tumorigenesis and progression of hepatocellular carcinoma (HCC) is largely unknown. We aimed to assess the role of GSTZ1 in HCC and to reveal the underlying mechanisms, which may contribute to finding a potential therapeutic strategy against HCC. METHODS: We first analyzed GSTZ1 expression levels in paired human HCC and adjacent normal tissue specimens and the prognostic effect of GSTZ1 on HCC patients. Thereafter, we evaluated the role of GSTZ1 in aerobic glycolysis in HCC cells on the basis of the oxygen consumption rate (OCR) and extracellular acidification rate (ECAR). Furthermore, we assessed the effect of GSTZ1 on HCC proliferation, glutathione (GSH) concentration, levels of reactive oxygen species (ROS), and nuclear factor erythroid 2-related factor 2 (NRF2) signaling via gain- and loss- of GSTZ1 function in vitro. Moreover, we investigated the effect of GSTZ1 on diethylnitrosamine (DEN) and carbon tetrachloride (CCl4) induced hepatocarcinogenesis in a mouse model of HCC. RESULTS: GSTZ1 was downregulated in HCC, thus indicating a poor prognosis. GSTZ1 deficiency significantly promoted hepatoma cell proliferation and aerobic glycolysis in HCC cells. Moreover, loss of GSTZ1 function depleted GSH, increased ROS levels, and enhanced lipid peroxidation, thus activating the NRF2-mediated antioxidant pathway. Furthermore, Gstz1 knockout in mice promoted DEN/CCl4-induced hepatocarcinogenesis via activation of the NRF2 signaling pathway. Furthermore, the antioxidant agent N-acetylcysteine and NRF2 inhibitor brusatol effectively suppressed the growth of Gstz1-knockout HepG2 cells and HCC progression in Gstz1-/- mice. CONCLUSIONS: GSTZ1 serves as a tumor suppressor in HCC. GSH depletion caused by GSTZ1 deficiency elevates oxidative stress, thus constitutively activating the NRF2 antioxidant response pathway and accelerating HCC progression. Targeting the NRF2 signaling pathway may be a promising therapeutic approach for this subset of HCC.

3.
Sensors (Basel) ; 19(23)2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31756902

RESUMO

In this paper, the performance of orthogonal fluxgate sensors with meander-shaped cores is studied in fundamental mode. The meander-shaped cores are made by micro-patterning technology based on a Co-based amorphous ribbon. The main advantage of this structure is that the linear operating range of the sensor can be adjusted simply by changing the number of strips, without affecting the excitation mechanism. Experiments show that a linear range of 560 µT is obtained by a meander-shaped core sensor with 12 strips. The changes in the number of strips can also increase sensitivity and reduce noise of the sensor. We can achieve a sensitivity of 600 V/T and a noise level of 0.64 nT/√Hz at 1 Hz for a meander-shaped core sensor with eight strips. Compared with the performance of the sensors built using a single strip core having the same equivalent cross-sectional area, the use of meander-shaped core can provide a higher sensitivity and linearity, and a lower noise level. We also compare the performance of an eight-strip meander-shaped core orthogonal fluxgate operated in the fundamental and second-harmonic modes. Similar sensitivity for the two modes can be obtained by adjusting the excitation current. In this case, we find that the noise of sensor operating in fundamental mode is about five times lower than that of the sensor operating in second-harmonic mode. This can be interpreted as the suppression of Barkhausen noise by unipolar bias in the fundamental mode.

4.
Semin Nephrol ; 39(5): 484-495, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31514912

RESUMO

Acute kidney injury is a common complication after cardiac surgery that is associated with high postoperative morbidity and mortality. Levels of hemolysis are associated closely with the incidence and severity of kidney injury after cardiac surgery. Hemolysis is caused by prolonged surgical procedures and blood transfusions from cell-saver devices and is associated with the use of cardiopulmonary bypass. Plasma oxyhemoglobin is released into the circulation by damaged red blood cells that, via a dioxygenation reaction, depletes vascular nitric oxide (NO), a potent vasodilator molecule responsible for modulating organ perfusion and vascular homeostasis. Depleted plasma NO and increased levels of plasma oxyhemoglobin in the bloodstream lead to impairment of organ perfusion, inflammation, oxidative stress, and direct tubular injury, which, together, contribute to the development of renal injury after cardiac surgery. The administration of NO, a gas originally approved to treat pulmonary hypertension, maintains organ perfusion by preventing vascular NO depletion. In addition, this treatment improves cardiac output by reducing pulmonary vascular resistance and right heart workload. The clinical evidence of renal protection of NO gas therapy is supported by preclinical animal studies exploring the extrapulmonary protective effects of NO. Recent clinical trials showed a significant reduction of postoperative acute kidney injury when NO gas was administered during and after cardiac surgery.

5.
Cell Death Differ ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367013

RESUMO

Solute carrier family 27 member 5 (SLC27A5/FATP5) is involved in fatty acid transport and bile acid metabolism; however, little is known about its role in human diseases. Here, we first show that SLC27A5 expression is downregulated in hepatocellular carcinoma (HCC) by DNA hypermethylation, and reduced SCL27A5 expression contributes to tumor progression and poor prognosis. Both gain- and loss-of-function studies demonstrated that SLC27A5 has an antiproliferative effect on HCC cells in vitro and in vivo. Knockout of SLC27A5 increases polyunsaturated lipids, leading to increased NADP+/NADPH ratio, ROS production as well as lipid peroxidation and the subsequent accumulation of 4-hydroxy-2-nonenal (4-HNE) in hepatoma cells. Mass spectrometry analysis found that 4-HNE directly modifies cysteine residues (Cys513, 518) on KEAP1, thus leading KEAP1/NRF2 pathway activation and increases the expression levels of NRF2 target genes, such as TXNRD1. Further, SLC27A5 expression negatively correlates with TXNRD1 expression in hepatoma cells and clinical HCC samples, and blockade of NRF2/TXNRD1 using genetic approaches or inhibitors sensitizes SLC27A5-deficient hepatoma cells to sorafenib treatment. Collectively, we demonstrated that SLC27A5 acts as a novel tumor suppressor by suppressing TXNRD1 expression via the KEAP1/NRF2 pathway in HCC. Combination therapy of sorafenib and NRF2/TXNRD1 inhibitors may be a promising strategy in personalized HCC treatment.

6.
EMBO J ; 38(15): e101964, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31267557

RESUMO

The IGF1R signaling is important in the malignant progression of cancer. However, overexpression of IGF1R has not been properly assessed in HCC. Here, we revealed that GSTZ1-1, the enzyme in phenylalanine/tyrosine catabolism, is downregulated in HCC, and its expression was negatively correlated with IGF1R. Mechanistically, GSTZ1-1 deficiency led to succinylacetone accumulation, alkylation modification of KEAP1, and NRF2 activation, thus promoting IGF1R transcription by recruiting SP1 to its promoter. Moreover, inhibition of IGF1R or NRF2 significantly inhibited tumor-promoting effects of GSTZ1 knockout in vivo. These findings establish succinylacetone as an oncometabolite, and GSTZ1-1 as an important tumor suppressor by inhibiting NRF2/IGF1R axis in HCC. Targeting NRF2 or IGF1R may be a promising treatment approach for this subset HCC.

7.
Neuro Endocrinol Lett ; 40(1): 10-16, 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-31184817

RESUMO

Standard management protocols for patients with pheochromocytoma (PHEO) have been described in current guidelines. However, the standard management approach for cardiac surgical patients with concurrent clinically silent PHEO has not been established yet. The effects of open heart surgery and cardiopulmonary bypass (CPB) on PHEO presentation are poorly documented. Here, we report in detail the anesthetic management and hemodynamic changes in a case of CPB-assisted pulmonary valve replacement surgery with an incidentally discovered normotensive PHEO. A 55-year-old male with normotensive PHEO underwent an open heart pulmonary valve replacement surgery. Blood pressure (BP) fluctuated with an inherent alternation rhythm during the whole process of the surgery with a peak at 230/130 mmHg and nadir at 40/30 mm Hg. Administration of fluids and vasoconstrictor/vasodilator was used for BP optimization. However, the BP changed intractably with delayed responses to the optimization management. The hemodynamic instability observed in this case indicated that the risk of occurrence and severity of the PHEO crisis did not decrease in cases with previously silent PHEO and may be triggered in any clinical scenario, not in tumor removal procedures alone. Careful preoperative evaluation and preparation with multidisciplinary cooperation are of paramount importance for such patients because open chest cardiac surgery and CPB could complicate the situation. In addition, there is little evidence about the benefits of a combined cardiac surgery with PHEO resection in such a clinical scenario, which validates further investigation.

8.
Mikrochim Acta ; 186(4): 252, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-30903388

RESUMO

The authors describe an integrated microfluidic chip for immunodetection of the prostate specific antigen (PSA) by using giant magnetoimpedance (GMI) sensor. This chip contains an immunoreaction platform and a biomarker detection system. The immunoreaction platform contains an incubation chamber and a reactive chamber to implement immunological reaction in microfluidics. The system can detect PSA rapidly with ultra-high sensitivity. Both are fabricated by MEMS technology. Immunomagnetic beads (If PSA binds to its antibody (that is labeled with immunomagnetic beads; IMBs) it will be trapped on the surface of self-assembled film. Trapped IMBs generate a stray magnetic field under the magnetization of the external applied magnetic field and can be detected by the GMI sensor. The chip can detect PSA with a detection limit as low as 0.1 ng ∙ mL-1 and works in the 0.1 ng ∙ mL-1 to 20 ng ∙ mL-1 concentration range. Compared to established GMI biosensors, the magnetic microfluidic chip reduces assay time, and lends itself to fast detection. It also avoids complex handling steps, enhances reaction efficiency and decreases experimental errors. Graphical abstract An integrated magnetic microfluidic chip which contains immunoreaction platform and biomarker detection system was designed and microfabricated by micro-electromechanical systems (MEMS) technology to detect prostate specific antigen (PSA) rapidly, and has promise in Point-of-care (PoC) diagnostic applications.

9.
N. Engl. j. med. ; 380(13): 1214-1225, Mar. 2019. gráfico, tabela
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1024163

RESUMO

BACKGROUND: Volatile (inhaled) anesthetic agents have cardioprotective effects, which might improve clinical outcomes in patients undergoing coronary-artery bypass grafting (CABG). METHODS: We conducted a pragmatic, multicenter, single-blind, controlled trial at 36 centers in 13 countries. Patients scheduled to undergo elective CABG were randomly assigned to an intraoperative anesthetic regimen that included a volatile anesthetic (desflurane, isoflurane, or sevoflurane) or to total intravenous anesthesia. The primary outcome was death from any cause at 1 year. RESULTS: A total of 5400 patients were randomly assigned: 2709 to the volatile anesthetics group and 2691 to the total intravenous anesthesia group. On-pump CABG was performed in 64% of patients, with a mean duration of cardiopulmonary bypass of 79 minutes. The two groups were similar with respect to demographic and clinical characteristics at baseline, the duration of cardiopulmonary bypass, and the number of grafts. At the time of the second interim analysis, the data and safety monitoring board advised that the trial should be stopped for futility. No significant difference between the groups with respect to deaths from any cause was seen at 1 year (2.8% in the volatile anesthetics group and 3.0% in the total intravenous anesthesia group; relative risk, 0.94; 95% confidence interval [CI], 0.69 to 1.29; P = 0.71), with data available for 5353 patients (99.1%), or at 30 days (1.4% and 1.3%, respectively; relative risk, 1.11; 95% CI, 0.70 to 1.76), with data available for 5398 patients (99.9%). There were no significant differences between the groups in any of the secondary outcomes or in the incidence of prespecified adverse events, including myocardial infarction. CONCLUSIONS: Among patients undergoing elective CABG, anesthesia with a volatile agent did not result in significantly fewer deaths at 1 year than total intravenous anesthesia. (Funded by the Italian Ministry of Health; MYRIAD ClinicalTrials.gov number, NCT02105610.). (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Ponte de Artéria Coronária , Anestésicos Inalatórios , Anestesia Geral , Anestesia Intravenosa
10.
Acta Pharmacol Sin ; 40(9): 1205-1211, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30867543

RESUMO

Corneal wounds usually heal quickly; but diabetic patients have more fragile corneas and experience delayed and painful healing. In the present study, we compared the healing capacity of corneal epithelial cells (CECs) between normal and diabetic conditions and the potential mechanisms. Primary murine CEC derived from wild-type and diabetic (db/db) mice, as well as primary human CEC were prepared. Human CEC were exposed to high glucose (30 mM) to mimic diabetic conditions. Cell migration and proliferation were assessed using Scratch test and MTT assays, respectively. Reactive oxygen species (ROS) production in the cells was measured using dichlorofluorescein reagent. Western blot was used to evaluate the expression levels of Akt. Transepithelial electrical resistance (TEER) and zonula occludens-1 (ZO-1) expression were used to determine tight junction integrity. We found that the diabetic CEC displayed significantly slower cell proliferation and migration compared with the normal CEC from both mice and humans. Furthermore, ROS production was markedly increased in CEC grown under diabetic conditions. Treatment with an antioxidant N-acetyl cysteine (NAC, 100 µM) significantly decreased ROS production and increased wound healing in diabetic CEC. Barrier function was significantly reduced in both diabetic mouse and human CEC, while NAC treatment mitigated these effects. We further showed that Akt signaling was impaired in diabetic CEC, which was partially improved by NAC treatment. These results show that diabetic conditions lead to delayed wound-healing capacity of CEC and impaired tight junction formation in both mice and human. Increased ROS production and inhibited Akt signaling may contribute to this outcome, implicating these as potential targets for treating corneal wounds in diabetic patients.

11.
N Engl J Med ; 380(13): 1214-1225, 2019 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-30888743

RESUMO

BACKGROUND: Volatile (inhaled) anesthetic agents have cardioprotective effects, which might improve clinical outcomes in patients undergoing coronary-artery bypass grafting (CABG). METHODS: We conducted a pragmatic, multicenter, single-blind, controlled trial at 36 centers in 13 countries. Patients scheduled to undergo elective CABG were randomly assigned to an intraoperative anesthetic regimen that included a volatile anesthetic (desflurane, isoflurane, or sevoflurane) or to total intravenous anesthesia. The primary outcome was death from any cause at 1 year. RESULTS: A total of 5400 patients were randomly assigned: 2709 to the volatile anesthetics group and 2691 to the total intravenous anesthesia group. On-pump CABG was performed in 64% of patients, with a mean duration of cardiopulmonary bypass of 79 minutes. The two groups were similar with respect to demographic and clinical characteristics at baseline, the duration of cardiopulmonary bypass, and the number of grafts. At the time of the second interim analysis, the data and safety monitoring board advised that the trial should be stopped for futility. No significant difference between the groups with respect to deaths from any cause was seen at 1 year (2.8% in the volatile anesthetics group and 3.0% in the total intravenous anesthesia group; relative risk, 0.94; 95% confidence interval [CI], 0.69 to 1.29; P = 0.71), with data available for 5353 patients (99.1%), or at 30 days (1.4% and 1.3%, respectively; relative risk, 1.11; 95% CI, 0.70 to 1.76), with data available for 5398 patients (99.9%). There were no significant differences between the groups in any of the secondary outcomes or in the incidence of prespecified adverse events, including myocardial infarction. CONCLUSIONS: Among patients undergoing elective CABG, anesthesia with a volatile agent did not result in significantly fewer deaths at 1 year than total intravenous anesthesia. (Funded by the Italian Ministry of Health; MYRIAD ClinicalTrials.gov number, NCT02105610.).


Assuntos
Anestesia Intravenosa , Anestésicos Gerais/farmacologia , Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Administração por Inalação , Idoso , Anestesia Geral , Anestésicos Intravenosos , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/fisiopatologia , Procedimentos Cirúrgicos Eletivos , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mortalidade , Método Simples-Cego , Volume Sistólico
13.
Sci Rep ; 8(1): 12817, 2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30127524

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

14.
Am J Respir Crit Care Med ; 198(10): 1279-1287, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29932345

RESUMO

RATIONALE: No medical intervention has been identified that decreases acute kidney injury and improves renal outcome at 1 year after cardiac surgery. OBJECTIVES: To determine whether administration of nitric oxide reduces the incidence of postoperative acute kidney injury and improves long-term kidney outcomes after multiple cardiac valve replacement requiring prolonged cardiopulmonary bypass. METHODS: Two hundred and forty-four patients undergoing elective, multiple valve replacement surgery, mostly due to rheumatic fever, were randomized to receive either nitric oxide (treatment) or nitrogen (control). Nitric oxide and nitrogen were administered via the gas exchanger during cardiopulmonary bypass and by inhalation for 24 hours postoperatively. MEASUREMENTS AND MAIN RESULTS: The primary outcome was as follows: oxidation of ferrous plasma oxyhemoglobin to ferric methemoglobin was associated with reduced postoperative acute kidney injury from 64% (control group) to 50% (nitric oxide group) (relative risk [RR], 0.78; 95% confidence interval [CI], 0.62-0.97; P = 0.014). Secondary outcomes were as follows: at 90 days, transition to stage 3 chronic kidney disease was reduced from 33% in the control group to 21% in the treatment group (RR, 0.64; 95% CI, 0.41-0.99; P = 0.024) and at 1 year, from 31% to 18% (RR, 0.59; 95% CI, 0.36-0.96; P = 0.017). Nitric oxide treatment reduced the overall major adverse kidney events at 30 days (RR, 0.40; 95% CI, 0.18-0.92; P = 0.016), 90 days (RR, 0.40; 95% CI, 0.17-0.92; P = 0.015), and 1 year (RR, 0.47; 95% CI, 0.20-1.10; P = 0.041). CONCLUSIONS: In patients undergoing multiple valve replacement and prolonged cardiopulmonary bypass, administration of nitric oxide decreased the incidence of acute kidney injury, transition to stage 3 chronic kidney disease, and major adverse kidney events at 30 days, 90 days, and 1 year. Clinical trial registered with ClinicalTrials.gov (NCT01802619).

15.
Sensors (Basel) ; 18(6)2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29857573

RESUMO

Cardiac biomarkers (CBs) are substances that appear in the blood when the heart is damaged or stressed. Measurements of the level of CBs can be used in course of diagnostics or monitoring the state of the health of group risk persons. A multi-region bio-analytical system (MRBAS) based on magnetoimpedance (MI) changes was proposed for ultrasensitive simultaneous detection of CBs myoglobin (Mb) and C-reactive protein (CRP). The microfluidic device was designed and developed using standard microfabrication techniques for their usage in different regions, which were pre-modified with specific antibody for specified detection. Mb and CRP antigens labels attached to commercial Dynabeads with selected concentrations were trapped in different detection regions. The MI response of the triple sensitive element was carefully evaluated in initial state and in the presence of biomarkers. The results showed that the MI-based bio-sensing system had high selectivity and sensitivity for detection of CBs. Compared with the control region, ultrasensitive detections of CRP and Mb were accomplished with the detection limits of 1.0 pg/mL and 0.1 pg/mL, respectively. The linear detection range contained low concentration detection area and high concentration detection area, which were 1 pg/mL⁻10 ng/mL, 10⁻100 ng/mL for CRP, and 0.1 pg/mL⁻1 ng/mL, 1 n/mL⁻80 ng/mL for Mb. The measurement technique presented here provides a new methodology for multi-target biomolecules rapid testing.


Assuntos
Biomarcadores/química , Técnicas Biossensoriais , Proteína C-Reativa/isolamento & purificação , Mioglobina/isolamento & purificação , Proteína C-Reativa/química , Impedância Elétrica , Humanos , Dispositivos Lab-On-A-Chip , Limite de Detecção , Nanopartículas de Magnetita/química , Mioglobina/química , Troponina I/química , Troponina I/isolamento & purificação
16.
PLoS One ; 13(3): e0194631, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29601593

RESUMO

A sensitive and innovative assay system based on a micro-MEMS-fluxgate sensor and immunomagnetic beads-labels was developed for the rapid analysis of C-reactive proteins (CRP). The fluxgate sensor presented in this study was fabricated through standard micro-electro-mechanical system technology. A multi-loop magnetic core made of Fe-based amorphous ribbon was employed as the sensing element, and 3-D solenoid copper coils were used to control the sensing core. Antibody-conjugated immunomagnetic microbeads were strategically utilized as signal tags to label the CRP via the specific conjugation of CRP to polyclonal CRP antibodies. Separate Au film substrates were applied as immunoplatforms to immobilize CRP-beads labels through classical sandwich assays. Detection and quantification of the CRP at different concentrations were implemented by detecting the stray field of CRP labeled magnetic beads using the newly-developed micro-fluxgate sensor. The resulting system exhibited the required sensitivity, stability, reproducibility, and selectivity. A detection limit as low as 0.002 µg/mL CRP with a linearity range from 0.002 µg/mL to 10 µg/mL was achieved, and this suggested that the proposed biosystem possesses high sensitivity. In addition to the extremely low detection limit, the proposed method can be easily manipulated and possesses a quick response time. The response time of our sensor was less than 5 s, and the entire detection period for CRP analysis can be completed in less than 30 min using the current method. Given the detection performance and other advantages such as miniaturization, excellent stability and specificity, the proposed biosensor can be considered as a potential candidate for the rapid analysis of CRP, especially for point-of-care platforms.


Assuntos
Técnicas Biossensoriais/instrumentação , Proteína C-Reativa/análise , Limite de Detecção , Sistemas Microeletromecânicos , Animais , Bovinos , Imãs , Microesferas , Sistemas Automatizados de Assistência Junto ao Leito , Fatores de Tempo
17.
Opt Express ; 25(21): 24861-24871, 2017 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-29041159

RESUMO

The chirality of photons plays a fundamental role in light-matter interactions. However, a limiting factor in photonic integrated circuits is the lack of a miniaturized component, which can distinguish the chirality in a low cost and integrated manner. Herein we numerically demonstrate a chirality-distinguishing beamsplitter that can address this challenge. It consists of an integrated polarization rotator and a linear polarization beamsplitter, which together can fulfill the task of distinguishing and splitting left- and right-handed quasi-circularly polarized modes on a chip with an ultra-broadband operation range from 1.45 µm to 1.65 µm. Owning to the reciprocity, the device can emit photons with selectable spin angular momentum depending on the chosen feeding waveguide. The device is compatible with complementary metal-oxide semiconductor technology and it may open up new avenues in the fields of on-chip nano-photonics, bio-photonics and quantum information science.

18.
Sci Rep ; 7(1): 12967, 2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-29021533

RESUMO

We report an innovative integrated microfluidic platform based on micro-fluxgate and micro-coils for trapping and detecting magnetic beads. A micro-spiral coil fabricated by microfabrication technology is used to trap the magnetic beads, and the micro-fluxgate is employed to detect the weak magnetic field induced by the trapped magnetic beads. The fabrication process of the magnetic bead trapping system using a micro-coil is highly compatible with that of the micro-fluxgate sensor, making fabrication of this integrated microfluidic system convenient and efficient. It is observed that the magnetic bead trapping ratio increases as the number of magnetic beads is increased with a flow rate of 5 to 16.5 µL·min-1. Samples spiked with different concentrations of magnetic beads can be distinguished clearly using the micro-fluxgate sensor in this microfluidic system. In this study, the results demonstrate that the microfluidic system traps and detects magnetic beads efficiently and is a promising candidate for biomarker capture and detection.

19.
Contemp Clin Trials ; 59: 38-43, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28533194

RESUMO

OBJECTIVE: There is initial evidence that the use of volatile anesthetics can reduce the postoperative release of cardiac troponin I, the need for inotropic support, and the number of patients requiring prolonged hospitalization following coronary artery bypass graft (CABG) surgery. Nevertheless, small randomized controlled trials have failed to demonstrate a survival advantage. Thus, whether volatile anesthetics improve the postoperative outcome of cardiac surgical patients remains uncertain. An adequately powered randomized controlled trial appears desirable. DESIGN: Single blinded, international, multicenter randomized controlled trial with 1:1 allocation ratio. SETTING: Tertiary and University hospitals. INTERVENTIONS: Patients (n=10,600) undergoing coronary artery bypass graft will be randomized to receive either volatile anesthetic as part of the anesthetic plan, or total intravenous anesthesia. MEASUREMENTS AND MAIN RESULTS: The primary end point of the study will be one-year mortality (any cause). Secondary endpoints will be 30-day mortality; 30-day death or non-fatal myocardial infarction (composite endpoint); cardiac mortality at 30day and at one year; incidence of hospital re-admission during the one year follow-up period and duration of intensive care unit, and hospital stay. The sample size is based on the hypothesis that volatile anesthetics will reduce 1-year unadjusted mortality from 3% to 2%, using a two-sided alpha error of 0.05, and a power of 0.9. CONCLUSIONS: The trial will determine whether the simple intervention of adding a volatile anesthetic, an intervention that can be implemented by all anesthesiologists, can improve one-year survival in patients undergoing coronary artery bypass graft surgery.


Assuntos
Anestesia em Procedimentos Cardíacos , Anestésicos Inalatórios , Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Complicações Pós-Operatórias , Adulto , Anestesia em Procedimentos Cardíacos/efeitos adversos , Anestesia em Procedimentos Cardíacos/métodos , Anestésicos Inalatórios/administração & dosagem , Anestésicos Inalatórios/química , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/métodos , Ponte de Artéria Coronária/mortalidade , Doença da Artéria Coronariana/mortalidade , Feminino , Humanos , Masculino , Avaliação de Processos e Resultados (Cuidados de Saúde) , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Análise de Sobrevida , Volatilização
20.
Micromachines (Basel) ; 8(12)2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30400540

RESUMO

This paper reports a novel micro-fluxgate sensor based on a double-layer magnetic core of a Fe⁻Co⁻B-based amorphous ribbon. The melt-spinning technique was carried out to obtain a Fe⁻Co⁻B-based amorphous ribbon composite of Fe58.1Co24.9B16Si1, and the obtained amorphous ribbon was then annealed at 595 K for 1 h to benefit soft magnetic properties. The prepared ribbon showed excellent soft magnetic behavior with a high saturated magnetic intensity (Bs) of 1.74 T and a coercivity (Hc) of less than 0.2 Oe. Afterward, a micro-fluxgate sensor based on the prepared amorphous ribbon was fabricated via microelectromechanical systems (MEMS) technology combined with chemical wet etching. The resulting sensor exhibited a sensitivity of 1985 V/T, a wide linearity range of ±1.05 mT, and a perming error below 0.4 µT under optimal operating conditions with an excitation current amplitude of 70 mA at 500 kHz frequency. The minimum magnetic field noise was about 36 pT/Hz1/2 at 1 Hz under the same excitation conditions; a superior resolution of 5 nT was also achieved in the fabricated sensor. To the best of our knowledge, a compact micro-fluxgate sensor with such a high-resolution capability has not been reported elsewhere. The microsensor presented here with such improved characteristics may considerably enhance the development of micro-fluxgate sensors.

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