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1.
Small ; 20(8): e2305607, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37817357

RESUMO

The molecule-electrode coupling plays an essential role in photoresponsive devices with photochromic molecules, and the strong coupling between the molecule and the conventional electrodes leads to/ the quenching effect and limits the reversibility of molecular photoswitches. In this work, we developed a strategy of using transition metal dichalcogenides (TMDCs) electrodes to fabricate the thiol azobenzene (TAB) self-assembled monolayers (SAMs) junctions with the eutectic gallium-indium (EGaIn) technique. The current-voltage characteristics of the EGaIn/GaOx //TAB/TMDCs photoswitches showed an almost 100% reversible photoswitching behavior, which increased by ∼28% compared to EGaIn/GaOx //TAB/AuTS photoswitches. Density functional theory (DFT) calculations showed the coupling strength of the TAB-TMDCs electrode decreased by 42% compared to that of the TAB-AuTS electrode, giving rise to improved reversibility. our work demonstrated the feasibility of 2D TMDCs for fabricating SAMs-based photoswitches with unprecedentedly high reversibility.

2.
Chemistry ; : e202402095, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943462

RESUMO

In the cross-plane single-molecule junctions, the correlation between molecular aromaticity and conductance remained puzzling. Cross-plane break junction (XPBJ) provides new insight into understanding the role of aromaticity and conjugation to molecules on charge transport through the planar molecules. In this work, we investigated the modulation of cross-plane charge transport in pyrene derivatives by hydrogenation and substituents based on the XPBJ method that differs from those used in-plane transport. We measured the electrical conductance of the hydrogenated derivatives of the pyrenes and found that hydrogenation reduces conductance, and the fully hydrogenated molecule has the lowest conductance. Conductance of pyrene derivatives increased after substitution by both electron-donating and electron-withdrawing groups. By calculating, the trend in decreased conductance of hydrogenated pyrene was found to be consistent with the change in aromaticity. Electron-withdrawing substituents reduce the aromaticity of the molecule and narrow the HOMO-LUMO gap, while electron-donating groups increase the aromaticity but also narrow the gap. Our work reveals the potential of fine-tuning the structure of the pyrene molecule to control the cross-plane charge transport through the single-molecule junctions.

3.
Nano Lett ; 23(20): 9399-9405, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37877237

RESUMO

An accurate rule for predicting conductance is the cornerstone of developing molecular circuits and provides a promising solution for miniaturizing electric circuits. The successful prediction of series molecular circuits has proven the possibility of establishing a rule for molecular circuits under quantum mechanics. However, the quantitatively accurate prediction has not been validated by experiments for parallel molecular circuits. Here we used 1,3-dihydrobenzothiophene (DBT) to build the parallel molecular circuits. The theoretical simulation and single-molecule conductance measurements demonstrated that the conductance of the molecule containing one DBT is the unprecedented linear combination of the conductance of the two individual channels with respective contribution weights of 0.37 and 0.63. With these weights, the conductance of the molecule containing two DBTs is predicted as 1.81 nS, matching perfectly with the measured conductance (1.82 nS). This feature offers a potential rule for quantitatively predicting the conductance of parallel molecular circuits.

4.
Molecules ; 29(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38893316

RESUMO

For designing single-molecule devices that have both conjugation systems and structural flexibility, a hyperconjugated molecule with a σ-π bond interaction is considered an ideal candidate. In the investigation of conductance at the single-molecule level, since few hyperconjugation systems have been involved, the strategy of building hyperconjugation systems and the mechanism of electron transport within this system remain unexplored. Based on the skipped-conjugated structure, we present a rational approach to construct a hyperconjugation molecule using a hydroxyl group, which serves as a bridge to interact with the conjugated fragments. The measurement of single-molecule conductance reveals a two-fold conductance enhancement of the hyperconjugation system having the 'bridging' hydroxyl group compared to hydroxyl-free derivatives. Theoretical studies demonstrate that the hydroxyl group in the hyperconjugation system connects the LUMO of the two conjugated fragments and opens a through-space channel for electron transport to enhance the conductance.

5.
Angew Chem Int Ed Engl ; 61(40): e202210097, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35981229

RESUMO

The Fano resonance in single-molecule junctions could be created by interaction with discrete and continuous molecular orbitals and enables effective electron transport modulation between constructive and destructive interference within a small energy range. However, direct observation of Fano resonance remains unexplored because of the disappearance of discrete orbitals by molecule-electrode coupling. We demonstrated the room-temperature observation of Fano resonance from electrochemical gated single-molecule conductance and current-voltage measurements of a para-carbazole anion junction. Theoretical calculations reveal that the negative charge on the nitrogen atom induces a localized HOMO on the molecular center, creating Fano resonance by interfering with the delocalized LUMO on the molecular backbone. Our findings demonstrate that the Fano resonance in electron transport through single-molecule junctions opens pathways for designs of interference-based electronic devices.

6.
Small ; 16(39): e2002808, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32851802

RESUMO

As stated in the classic Kirchhoff's circuit laws, the total conductance of two parallel channels in an electronic circuit is the sum of the individual conductance. However, in molecular circuits, the quantum interference (QI) between the individual channels may lead to apparent invalidity of Kirchhoff's laws. Such an effect can be very significant in single-molecule circuits consisting of partially overlapped multiple transport channels. Herein, an investigation on how the molecular circuit conductance correlates to the individual channels is conducted in the presence of QI. It is found that the conductance of multi-channel circuit consisting of both constructive and destructive QI is significantly smaller than the addition of individual ones due to the interference between channels. In contrast, the circuit consisting of destructive QI channels exhibits an additive transport. These investigations provide a new cognition of transport mechanism and manipulation of transport in multi-channel molecular circuits.

7.
J Am Chem Soc ; 140(21): 6531-6535, 2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29690767

RESUMO

Distinguishing structural isomers at the single-molecule level remains a challenge. We report the single-molecule recognition of two diketopyrrolopyrrole containing isomers (SDPP and SPPO) employing the mechanically controllable break junction technique. The single-molecule conductances of the two isomers are indistinguishable under normal conditions. However, reversible protonation and deprotonation of the SPPO in molecular junction result in more than 1 order of magnitude conductance change, which dramatically enhances the conductance difference between the two isomers. Theoretical study reveals that the dramatic conductance switching is due to reversible quantum interference effect. It is suggested that combination of stimuli-response and quantum interference can be an efficient strategy to enhance isomer recognition and conductance switching in single-molecule junctions.

9.
Angew Chem Int Ed Engl ; 56(42): 13031-13035, 2017 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-28763147

RESUMO

The design and synthesis of high-performance n-type organic semiconductors are important for the development of future organic optoelectronics. Facile synthetic routes to reach the K-region of pyrene and produce 4,5,9,10-pyrene diimide (PyDI) derivatives are reported. The PyDI derivatives exhibited efficient electron transport properties, with the highest electron mobility of up to 3.08 cm2 V-1 s-1 . The tert-butyl-substituted compounds (t-PyDI) also showed good one- and two-photon excited fluorescence properties. The PyDI derivatives are a new family of aromatic diimides that may exhibit both high electron mobility and good light-emitting properties, thus making them excellent candidates for future optoelectronics.

10.
Birth ; 42(3): 242-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26095672

RESUMO

BACKGROUND: Although policies have been implemented to improve a breastfeeding-friendly environment, few studies have examined the effectiveness of these policies in Taiwan. We examined progress in breastfeeding environmental factors from 2008 through 2011 in Taiwan and their association with continuing exclusive and any breastfeeding until 6 months postpartum. METHODS: This study was a secondary data analysis, using four cross-sectional and national surveys of 1,453-12,410 postpartum women in the years 2008 through 2011. Data were collected by telephone interviews, using structured questionnaires with randomly selected postpartum women who gave birth in the indicated years. Results were weighted to enhance representativeness. Logistic regression was used to compute adjusted odds ratios for the use of breastfeeding-friendly services on breastfeeding continuation. RESULTS: The rates of breastfeeding at 6 months postpartum generally increased from 2008 to 2011, despite a drop in 2010. The use of breastfeeding-friendly environmental factors, including breastfeeding rooms in public places or workplaces, breastfeeding consultation phone lines/websites, breastfeeding volunteers, and delivery in baby-friendly hospitals, increased from 2008 to 2011. However, the percentage of women participating in breastfeeding support groups decreased during that period. After controlling for maternal characteristics, use of each of the breastfeeding-friendly environmental factors was significantly and positively associated with continuing breastfeeding until 6 months postpartum. The adjusted odds ratios for breastfeeding-friendly environmental factors ranged from 1.15 to 5.04. CONCLUSIONS: The breastfeeding-friendly environment and long-term breastfeeding rates in Taiwan improved from 2008 to 2011, supporting the effectiveness of policy and public health efforts.


Assuntos
Aleitamento Materno/estatística & dados numéricos , Aleitamento Materno/tendências , Cuidado Pós-Natal/legislação & jurisprudência , Adulto , Estudos Transversais , Meio Ambiente , Feminino , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Razão de Chances , Licença Parental , Gravidez , Apoio Social , Inquéritos e Questionários , Taiwan , Adulto Jovem
11.
Birth ; 41(1): 33-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24654635

RESUMO

OBJECTIVES: We examined progress in the practice of early skin-to-skin contact and rooming-in, and their association with breastfeeding, using national samples of postpartum women in the years 2004 and 2011 in Taiwan. METHODS: This study was a secondary data analysis using 2004 and 2011 national surveys of 12,201 and 12,405 postpartum women, respectively. RESULTS: More women had early skin-to-skin contact in 2011 than in 2004 (54.9% vs 20.6%, p < 0.001). Although fewer women practiced rooming-in in 2011 than in 2004 (33.8% vs 45.8%, p < 0.001), the percentage of women rooming-in for 24 hours improved from 6.1 percent to 22.7 percent from 2004 to 2011, and for rooming-in from 12 to less than 24 hours, the percentage improved from 4.3 percent to 10.9 percent (p < 0.001). The rate of breastfeeding increased by 50 percent during hospitalization (from 57.4% to 85.6%) and by 150 percent at 6 months postpartum (from 20.1% to 50.2%). After adjustment for background characteristics, women who had early skin-to-skin contact were more than twice as likely to breastfeed their infants during hospitalization, and about 1.2 times as likely to breastfeed at 6 months postpartum. The odds ratio for breastfeeding at 6 months generally increased as the duration of rooming-in increased in 2004 (OR ranged from 1.37 to 2.47). In 2011, only rooming-in for 12 to less than 24 hours (OR = 1.31) and 24 hours (OR = 1.98) daily significantly increased the odds ratio for breastfeeding at 6 months postpartum. CONCLUSIONS: Significant improvements in early skin-to-skin contact, the duration of rooming-in, and breastfeeding were observed in Taiwan. Early skin-to-skin contact and rooming-in for more than 12 hours were associated with increased chances for exclusive breastfeeding and breastfeeding at 6 months postpartum.


Assuntos
Aleitamento Materno/tendências , Posicionamento do Paciente/tendências , Cuidado Pós-Natal/tendências , Alojamento Conjunto/tendências , Adulto , Feminino , Humanos , Recém-Nascido , Razão de Chances , Taiwan , Adulto Jovem
12.
Int Urol Nephrol ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578391

RESUMO

PURPOSE: The purpose of the study was to explore the predictive value of free triiodothyronine to free thyroxine ratio (FT3/FT4) on contrast-associated acute kidney injury (CA-AKI) and poor prognosis in euthyroid patients after percutaneous coronary intervention (PCI). METHODS: The present study included 3,116 euthyroid patients who underwent elective PCI. The main outcome was CA-AKI, and the secondary outcome was long-term mortality. All patients were divided into three groups according to the tertiles of FT3/FT4 levels. RESULTS: During hospitalization, a total of 160 cases (5.1%) of CA-AKI occurred. Restricted cubic spline (RCS) analysis indicated a linear and negative relationship between FT3/FT4 and CA-AKI risk (P for nonlinearity = 0.2621). Besides, the fully-adjusted logistic regression model revealed that patients in tertile 3 (low FT3/FT4 group) had 1.82 times [odds ratio (OR): 1.82, 95% confidence interval (CI): 1.13-3.02, P = 0.016] as high as the risk of CA-AKI than those in tertile 1 (high FT3/FT4 group). Similarly, patients in tertile 3 were observed to have a higher incidence of long-term mortality [fully-adjusted hazard ratio (HR): 1.58, 95% CI: 1.07-2.32, P = 0.021]. Similarly, the Kaplan-Meier curves displayed significant differences in long-term mortality among the three groups (log-rank test, P < 0.001). CONCLUSION: In euthyroid patients undergoing elective PCI, low levels of FT3/FT4 were independently associated with an increased risk of CA-AKI and long-term mortality. Routine evaluation of FT3/FT4 may aid in risk stratification and guide treatment decisions within this particular patient group.

13.
Clin Interv Aging ; 19: 411-420, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476830

RESUMO

Purpose: The estimated glomerular filtration rate (eGFR) based on creatinine is crucial for the risk assessment of contrast-associated acute kidney injury (CA-AKI). In recent, the difference between cystatin C-based eGFR (eGFRcys) and creatinine-based eGFR (eGFRcr) has been widely documented. We aimed to explore whether intraindividual differences between eGFRcys and eGFRcr had potential value for CA-AKI risk assessment in patients undergoing elective percutaneous coronary intervention (PCI). Patients and Methods: From January 2012 to December 2018, we retrospectively observed 5049 patients receiving elective PCI. To determine eGFR, serum creatinine and cystatin C levels were measured. CA-AKI was defined as serum creatinine being increased ≥ 50% or 0.3 mg/dL within 48 h after contrast agents exposure. Chronic kidney disease (CKD) was defined as the eGFR < 60 mL/min/1.73 m2. Results: Approximately half of the participants (2479, 49.1%) had a baseline eGFRdiff (eGFRcys-eGFRcr) between -15 and 15 mL/min/1.73 m2. Restricted cubic splines analysis revealed a nonlinear relationship between eGFRdiff and CA-AKI. Multivariable logistic regression analysis indicated that compared with the reference group (-15 to 15 mL/min/1.73 m2), the negative-eGFRdiff group (less than -15 mL/min/1.73 m2) had a higher risk of CA-AKI (OR, 3.44; 95% CI, 2.57-4.64). Furthermore, patients were divided into four groups based on CKD identified by eGFRcys or eGFRcr. Multivariable logistic analysis revealed that patients with either CKDcys (OR, 2.94; 95% CI, 2.19-3.95, P < 0.001) or CKDcr (OR, 2.44; 95% CI, 1.19-4.63, P < 0.001) had an elevated risk of CA-AKI compared to those without CKDcys and CKDcr. Conclusion: There are frequent intraindividual differences between eGFRcys and eGFRcr, and these differences can be used to forecast the risk of CA-AKI.


Assuntos
Injúria Renal Aguda , Intervenção Coronária Percutânea , Insuficiência Renal Crônica , Humanos , Cistatina C , Creatinina , Estudos Retrospectivos , Taxa de Filtração Glomerular
14.
Clin Cardiol ; 47(2): e24219, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38402549

RESUMO

PURPOSE: Inflammation is commonly considered a mechanism underlying contrast-associated acute kidney injury (CA-AKI). This study aimed to explore the predictive capability of the novel inflammatory marker lactate dehydrogenase-to-albumin ratio (LAR) for CA-AKI following percutaneous coronary intervention (PCI), and further compare it with other common inflammatory biomarkers. METHODS: This study enrolled 5,435 patients undergoing elective PCI. The primary outcome was CA-AKI, and the secondary outcome was all-cause mortality. All patients were grouped into three groups based on the LAR tertiles. RESULTS: Three hundred fifteen patients (5.8%) experienced CA-AKI during hospitalization. The fully adjusted logistic regression suggested a significant increase in the risk of CA-AKI in LAR Tertile 3 (odds ratio [OR]: 2.51, 95% confidence interval [CI]: 1.68-3.83, p < .001) and Tertile 2 (OR: 2.11, 95% CI: 1.42-3.20, p < .001) compared to Tertile 1. Additionally, receiver operating characteristic (ROC) analysis demonstrated that LAR exhibited significantly superior predictive capability for CA-AKI compared to other inflammatory biomarkers. Regarding the secondary outcome, multivariate COX regression analysis showed a positive correlation between elevated LAR levels and all-cause mortality. CONCLUSION: In patients undergoing elective PCI, LAR was significantly independently associated with CA-AKI, and it stood out as the optimal inflammatory biomarker for predicting CA-AKI.


Assuntos
Injúria Renal Aguda , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico , Albuminas , Biomarcadores , Lactato Desidrogenases
15.
Angiology ; : 33197241228051, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227840

RESUMO

The albumin-bilirubin (ALBI) score is considered an effective and convenient scoring system for assessing liver function. We hypothesized that the ALBI score was predictive of contrast-associated acute kidney injury (CA-AKI) and long-term mortality in patients undergoing elective percutaneous coronary intervention (PCI). We retrospectively observed 5629 patients undergoing elective PCI. Contrast-associated acute kidney injury is defined as a 50% or 0.3 mg/dl increase in baseline serum creatinine levels within 48 h of contrast exposure. The incidence of CA-AKI was 6.2% (n = 350). After adjusting for potential confounding factors, multivariate analysis showed that the ALBI score was an independent predictor of CA-AKI (P = .002). A restricted cubic spline analysis confirmed approximately linear relationships between the ALBI score and risks of CA-AKI. Furthermore, at a median follow-up of 2.8 years, multivariate Cox regression analysis indicated that the ALBI score was an independent risk factor for long-term mortality (P < .001). The ALBI score was closely related to the occurrence of CA-AKI and long-term mortality in patients who underwent elective PCI. This score might be useful for risk stratification in high-risk patient groups to predict CA-AKI.

16.
J Inflamm Res ; 16: 2845-2854, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37449284

RESUMO

Purpose: Prior research has demonstrated a key role of systemic inflammatory state in the pathogenesis and progression of contrast-associated acute kidney injury (CA-AKI). Recently, the systemic inflammation score (SIS) has been introduced to evaluate the inflammatory status, utilizing the lymphocyte-to-monocyte ratio (LMR) and albumin. The primary objective of this study was to determine whether the SIS can predict CA-AKI and long-term prognosis in patients undergoing elective percutaneous coronary intervention (PCI). Patients and Methods: A total of 5726 patients who underwent elective PCI were included from January 2012 to December 2018. The primary outcome was CA-AKI, defined as an increase in serum creatinine (SCr) ≥0.3 mg/dl or ≥50% than baseline SCr within 48 h after the PCI procedure. The secondary outcome was long-term mortality. All patients were classified into low- and high-SIS groups. Results: During hospitalization, 349 (6.1%) patients developed CA-AKI. Multivariate logistic regression analysis showed that patients in the high SIS group had a 1.47-fold higher risk of developing CA-AKI than those in the low SIS group [odds ratio (OR): 1.50, 95% confidence interval (CI): 1.12-2.01, P =0.006]. Furthermore, the SIS showed the greatest prediction performance for CA-AKI compared with other inflammatory hematological ratios. In the multivariate Cox regression analysis, the high SIS group was found to be closely associated with long-term mortality [hazard ratio (HR): 1.58, 95% CI: 1.26-1.97, P <0.001, vs low SIS group]. The Kaplan-Meier curve analysis also demonstrated a difference in long-term mortality between the two groups (Log rank test, P <0.001). Conclusion: The SIS was closely associated with CA-AKI and long-term mortality in patients after elective PCI. Thus, more attention should be paid to exploring the potential benefits of anti-inflammatory strategies in preventing CA-AKI and improving the prognosis of patients undergoing PCI.

17.
J Am Heart Assoc ; 12(1): e027980, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36565177

RESUMO

Background Shrunken pore syndrome (SPS) as a novel phenotype of renal dysfunction is characterized by a difference in renal filtration between cystatin C and creatinine. The manifestation of SPS was defined as a cystatin C-based estimated glomerular filtration rate (eGFR) <60% of the creatinine-based eGFR. SPS has been shown to be associated with the progression and adverse prognosis of various cardiovascular and renal diseases. However, the predictive value of SPS for contrast-associated acute kidney injury (CA-AKI) and long-term outcomes in patients undergoing percutaneous coronary intervention remains unclear. Methods and Results We retrospectively observed 5050 consenting patients from January 2012 to December 2018. Serum cystatin C and creatinine were measured and applied to corresponding 2012 and 2021 Chronic Kidney Disease Epidemiology Collaboration equations, respectively, to calculate the eGFR. Chronic kidney disease (CKD) was defined as a creatinine-based eGFR <60 mL/min per 1.73 m2 without dialysis. CA-AKI was defined as an increase in serum creatinine ≥50% or 0.3 mg/dL within 48 hours after contrast medium exposure. Overall, 649 (12.85%) patients had SPS, and 324 (6.42%) patients developed CA-AKI. Multivariate logistic regression analysis indicated that SPS was significantly associated with CA-AKI after adjusting for potential confounding factors (odds ratio [OR], 4.17 [95% CI, 3.17-5.46]; P<0.001). Receiver operating characteristic analysis indicated that the cystatin C-based eGFR:creatinine-based eGFR ratio had a better performance and stronger predictive power for CA-AKI than creatinine-based eGFR (area under the curve: 0.707 versus 0.562; P<0.001). Multivariate logistic analysis revealed that compared with those without CKD and SPS simultaneously, patients with CKD and non-SPS (OR, 1.70 [95% CI, 1.11-2.55]; P=0.012), non-CKD and SPS (OR, 4.02 [95% CI, 2.98-5.39]; P<0.001), and CKD and SPS (OR, 8.62 [95% CI, 4.67-15.7]; P<0.001) had an increased risk of CA-AKI. Patients with both SPS and CKD presented the highest risk of long-term mortality compared with those without both (hazard ratio, 2.30 [95% CI, 1.38-3.86]; P=0.002). Conclusions SPS is a new and more powerful phenotype of renal dysfunction for predicting CA-AKI than CKD and will bring new insights for an accurate clinical assessment of the risk of CA-AKI.


Assuntos
Injúria Renal Aguda , Insuficiência Renal Crônica , Humanos , Cistatina C , Creatinina , Estudos Retrospectivos , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico , Taxa de Filtração Glomerular , Fenótipo , Fatores de Risco
18.
Medicine (Baltimore) ; 100(14): e25299, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33832099

RESUMO

ABSTRACT: Intradialytic hypotension (IDH) may lead to a poor life quality and was associated with cardiovascular mortality in patients under hemodialysis. This study investigated the autonomic nerve and cardiovascular function in the IDH episodes.In this case-control study, 70 end stage renal disease patients (198 visits) were recruited. Pulse wave analysis and heart rate variability were evaluated before hemodialysis. Two definitions of IDH were confirmed by medical records. IDH-f indicated a drop of systolic blood pressure or mean arterial pressure, accompanied with symptoms; IDH-n indicated a low nadir systolic pressure during the hemodialysis. All parameters were evaluated for the possible predisposing factors under each definition.A total of 24 IDH-f and 37 IDH-n were noted in 177 visits. For both definitions, central pulse pressure seemed to be a consistent predisposing factor. Furthermore, lower sympathetic activity (odds ratio [OR] 0.55; 95% confidence interval [CI] 0.35-0.87), lower pulse pressure (OR 0.95; 95% CI 0.92-0.98), and higher augmentation index (OR 17.36; 95% CI 1.48-204.10) were the possible predisposing factors for IDH-f. On the contrary, lower mean arterial pressure (OR 0.87; 95% CI 0.78-0.98) was identified as the possible factor for IDH-n.It was suggested that the lower central pulse pressure and sympathetic activity might be involved in the development of IDH.


Assuntos
Hemodinâmica/fisiologia , Hipotensão/etiologia , Hipotensão/fisiopatologia , Falência Renal Crônica/terapia , Diálise Renal/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Estudos de Casos e Controles , Frequência Cardíaca , Humanos , Pessoa de Meia-Idade , Análise de Onda de Pulso
19.
JMIR Med Inform ; 8(10): e24305, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33124991

RESUMO

BACKGROUND: Patients with end-stage liver disease (ESLD) have limited treatment options and have a deteriorated quality of life with an uncertain prognosis. Early identification of ESLD patients with a poor prognosis is valuable, especially for palliative care. However, it is difficult to predict ESLD patients that require either acute care or palliative care. OBJECTIVE: We sought to create a machine-learning monitoring system that can predict mortality or classify ESLD patients. Several machine-learning models with visualized graphs, decision trees, ensemble learning, and clustering were assessed. METHODS: A retrospective cohort study was conducted using electronic medical records of patients from Wan Fang Hospital and Taipei Medical University Hospital. A total of 1214 patients from Wan Fang Hospital were used to establish a dataset for training and 689 patients from Taipei Medical University Hospital were used as a validation set. RESULTS: The overall mortality rate of patients in the training set and validation set was 28.3% (257/907) and 22.6% (145/643), respectively. In traditional clinical scoring models, prothrombin time-international normalized ratio, which was significant in the Cox regression (P<.001, hazard ratio 1.288), had a prominent influence on predicting mortality, and the area under the receiver operating characteristic (ROC) curve reached approximately 0.75. In supervised machine-learning models, the concordance statistic of ROC curves reached 0.852 for the random forest model and reached 0.833 for the adaptive boosting model. Blood urea nitrogen, bilirubin, and sodium were regarded as critical factors for predicting mortality. Creatinine, hemoglobin, and albumin were also significant mortality predictors. In unsupervised learning models, hierarchical clustering analysis could accurately group acute death patients and palliative care patients into different clusters from patients in the survival group. CONCLUSIONS: Medical artificial intelligence has become a cutting-edge tool in clinical medicine, as it has been found to have predictive ability in several diseases. The machine-learning monitoring system developed in this study involves multifaceted analyses, which include various aspects for evaluation and diagnosis. This strength makes the clinical results more objective and reliable. Moreover, the visualized interface in this system offers more intelligible outcomes. Therefore, this machine-learning monitoring system provides a comprehensive approach for assessing patient condition, and may help to classify acute death patients and palliative care patients. Upon further validation and improvement, the system may be used to help physicians in the management of ESLD patients.

20.
Nanoscale Horiz ; 5(10): 1420-1429, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32856666

RESUMO

Sb nanosheets, also known as antimonene, have received ever-growing consideration as a promising new type of two-dimensional (2D) material due to their many attractive properties. However, how their nonlinear optical (NLO) properties are affected by their nanosheet structure and measurement conditions remains unclear. Herein, we report a successful size-selective production method for Sb nanosheets, which is based on a combination of lithium ion intercalation, solvent exfoliation and size selection centrifugation. This high-yield and size-selective preparation method enables fundamental investigation on the relation of the intrinsic optical properties of Sb nanosheets. Nanosecond Z-scan measurements revealed a unique size-dependent broadband NLO response. When the average size is reduced from 3 micrometers to 50 nanometers, the Sb nanosheets exhibit a clear transition from saturable absorption to reversed saturable absorption. Ultrafast transient absorption spectroscopic investigation indicated that exciton cooling is significantly faster in a small nanosheet than in large ones, revealing that the different exciton relaxation dynamic plays key roles in the distinct size-tunable nonlinear optical response. This work paves new ways towards the mass production and practical application of antimonene.

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