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1.
Lipids Health Dis ; 23(1): 90, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38539207

RESUMEN

BACKGROUND: Blood stasis constitution in traditional Chinese medicine (TCM) is believed to render individuals more susceptible to metabolic diseases. However, the biological underpinnings of this constitutional imbalance remain unclear. METHODS: This study explored the association between blood stasis constitution, serum metabolic markers including uric acid (UA), high-density lipoprotein cholesterol (HDLC), their ratio (UHR), serum metabolites, and gut microbiota. Clinical data, fecal and serum samples were acquired from 24 individuals with a blood stasis constitution and 80 individuals with a balanced constitution among healthy individuals from Guangdong. Gut microbiota composition analysis and serum metabolomics analysis were performed. RESULTS: Females with a blood stasis constitution had higher UA levels, lower HDLC levels, and higher UHR in serum, suggesting a higher risk of metabolic abnormalities. Analysis of the gut microbiome revealed two distinct enterotypes dominated by Bacteroides or Prevotella. Intriguingly, blood stasis subjects were disproportionately clustered within the Bacteroides-rich enterotype. Metabolomic analysis identified subtle differences between the groups, including lower phenylalanine and higher trimethylaminoacetone levels in the blood stasis. Several differential metabolites displayed correlations with HDLC, UA, or UHR, unveiling potential new markers of metabolic dysregulation. CONCLUSIONS: These findings elucidate the intricate interplay between host constitution, gut microbiota, and serum metabolites. The concept of blood stasis offers a unique perspective to identify subtle alterations in microbiome composition and metabolic pathways, potentially signaling underlying metabolic vulnerability, even in the presence of ostensibly healthy profiles. Continued investigation of this TCM principle may reveal critical insights into the early biological processes that foreshadow metabolic deterioration.


Asunto(s)
Medicina Tradicional China , Ácido Úrico , Humanos , Femenino , HDL-Colesterol , Heces , Metabolómica , Biomarcadores
2.
Proc Natl Acad Sci U S A ; 118(21)2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-34001593

RESUMEN

Diffusion is generally faster at higher temperatures. Here, a counterintuitive behavior is observed in that the movement of long-chain molecules slows as the temperature increases under confinement. This report confirms that this anomalous diffusion is caused by the "thermal resistance effect," in which the diffusion resistance of linear-chain molecules is equivalent to that with branched-chain configurations at high temperature. It then restrains the molecular transportation in the nanoscale channels, as further confirmed by zero length column experiments. This work enriches our understanding of the anomalous diffusion family and provides fundamental insights into the mechanism inside confined systems.

3.
Ann Noninvasive Electrocardiol ; 25(4): e12748, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32103582

RESUMEN

BACKGROUND: Heart rate acceleration and deceleration capacities are novel parameters that can quantify sympathetic and vagal modulation. However, how acceleration and deceleration capacities associated with circadian blood pressure (BP) variation remains unknown. METHODS: A total of 141 patients with essential hypertension were included in our study. Based on the nocturnal decline rate of systolic BP (SBP), patients were divided into two groups, as dippers and nondippers. Baseline demographic characteristics, ambulatory blood pressure monitoring (ABPM) parameters, Holter recordings, and echocardiographic parameters were collected. RESULTS: The absolute values of acceleration capacity (AC) (-7.75 [-8.45 ~ -6.3] ms vs. -6.6 [-8.25 ~ -5.2] ms, p = .047) and deceleration capacity (DC) (7.35 [6.1 ~ 8.1] ms vs. 6.3 [5.1 ~ 7.6] ms, p = .042) were significantly higher in dippers than in nondippers. By multivariate logistic regression analysis, left atrial diameter (LAd) was found to be an independent risk factor for nondipper status in acceleration capacity model (odds ratio 1.174, 95% confidence interval 1.019-1.354, p = .027) and deceleration model (odds ratio 1.146, 95% confidence interval 1.003-1.309, p = .045). Sleep SBP was positively correlated to acceleration capacity (r = .256, p = .002) and negatively correlated to deceleration capacity (r = -.194, p = .021). CONCLUSIONS: The absolute values of acceleration capacity and deceleration capacity were higher in patients with dipper hypertension than in patients with nondipper hypertension. However, acceleration and deceleration capacities were not independent risk factors for blunted BP variation. Sleep SBP seemed to be better correlated to the impairment of autonomic nervous system (ANS) function than other ABPM parameters.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial/métodos , Ritmo Circadiano/fisiología , Ecocardiografía/métodos , Electrocardiografía Ambulatoria/métodos , Frecuencia Cardíaca/fisiología , Hipertensión/fisiopatología , Presión Sanguínea/fisiología , Femenino , Humanos , Hipertensión/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
4.
Cell Mol Biol (Noisy-le-grand) ; 65(7): 132-137, 2019 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-31880531

RESUMEN

A decrease in the rapid component of delayed rectifier potassium current (IKr) during chronic heart failure (CHF) prolongs action potential (AP), and plays a key role in the pathogenesis of ventricular arrhythmias. ß-Arrestin2 has been shown to restore the inotropic reserve of ß-adrenergic regulation, but little or nothing is known about its effect on intrinsic channel. This study investigated the role of ß-arrestin2 in the regulation of cardiac hERG/IKr potassium channel and AP during chronic adrenergic stimulation. Single left ventricular myocytes were isolated from guinea pig heart, and were transfected with adenovirus encoding ß-arrestin2, or ß-arrestin2 siRNA or an empty adenovirus. Cell cultures containing 10 nM isoproterenol, 1 nM phenylephrine or vehicle alone (control medium) were electro-physiologically examined after 48 h of incubation. Action potential duration at 50 and 90 % of repolarization (APD50 and APD90) were measured using whole-cell patch-clamp recording. Sustained adrenergic stimulation significantly reduced the density of the IKr current (p < 0.001). ß-Arrestin2 expression in cell cultures treated with isoproterenol or phenylephrine was significantly downregulated after adrenergic stimulation (p < 0.001). Overexpression of ß-arrestin2 significantly attenuated isoproterenol or phenylephrine-induced reduction in IKr current. It also prevented the phenylephrine-induced prolongation of AP (p < 0.05 for APD50 and p < 0.001 for APD90), but did not significantly affect AP profile after exposure of the cardiomyocytes to isoproterenol (p > 0.05). Therefore, Increased levels of ß-Arrestin2 weaken dysregulation of IKr current and prevent excessive AP prolongation, making it an effective anti-arrhythmic strategy.


Asunto(s)
Potenciales de Acción/fisiología , Arritmias Cardíacas/metabolismo , Miocitos Cardíacos/metabolismo , Canales de Potasio/metabolismo , Arrestina beta 2/metabolismo , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/genética , Animales , Células Cultivadas , Cobayas , Isoproterenol/farmacología , Masculino , Técnicas de Placa-Clamp , Fenilefrina/farmacología , Arrestina beta 2/genética
6.
Opt Express ; 24(5): 5431-5441, 2016 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-29092366

RESUMEN

We report a functional reflective polarizer that can be incorporated into a compact augmented reality system. The design principle of the functional reflective polarizer is explained and two design examples are illustrated. In the first example, with the specially designed functional reflective polarizer, the transmittance of the augment reality system is relatively high as compared to a polarizing beam splitter or a conventional reflective polarizer. Such a functional reflective polarizer can also be used for vehicular displays. For the second example, the functional reflective polarizer is specially tailored to help those people with color vision deficiency.

7.
Can J Physiol Pharmacol ; 94(9): 1023-32, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27376484

RESUMEN

The heterodimerized transcription factors CLOCK-BMAL1 regulate the cardiomyocyte circadian rhythms. The L-type calcium currents play important role in the cardiac electrogenesis and arrhythmogenesis. Whether and how the CLOCK-BMAL1 regulate the cardiac L-type calcium channels are yet to be determined. The functions of the L-type calcium channels were evaluated with patch clamping techniques. Recombinant adenoviruses of CLOCK and BMAL1 were used in the expression experiments. We reported that the expressions and functions of CACNA1C (the α-subunit of the L-type calcium channels) showed circadian rhythms, with the peak at zeitgeber time 3 (ZT3). The endocardial action potential durations 90 (APD90) were correspondingly longer at ZT3. The protein levels of the phosphorylated Akt at threonine 308 (pAkt T308) also showed circadian rhythms. Overexpressions of CLOCK-BMAL1 significantly reduced the levels of CACNA1C while increasing the levels of pAkt T308 and pik3r1. Furthermore, the inhibitory effects of CLOCK-BMAL1 on CACNA1C could be abolished by the Akt inhibitor MK2206 or the PDK1 inhibitor GSK2334470. Collectively, our findings suggested that the expressions of the cardiac CACNA1C were under the CLOCK-BMAL1 regulation, probably through the PI3K-Akt signal pathway.


Asunto(s)
Factores de Transcripción ARNTL/fisiología , Proteínas CLOCK/fisiología , Canales de Calcio Tipo L/metabolismo , Ritmo Circadiano/fisiología , Fosfatidilinositol 3-Quinasas/metabolismo , Subunidades de Proteína/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Factores de Transcripción ARNTL/antagonistas & inhibidores , Potenciales de Acción/fisiología , Animales , Proteínas CLOCK/antagonistas & inhibidores , Células Cultivadas , Cobayas , Compuestos Heterocíclicos con 3 Anillos/farmacología , Indazoles/farmacología , Miocitos Cardíacos/fisiología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Pirimidinas/farmacología , Transducción de Señal/fisiología
8.
BMC Complement Altern Med ; 16: 217, 2016 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-27411310

RESUMEN

BACKGROUND: Primary insomnia is a widespread and refractory disease. Moxibustion therapy for insomnia shows some advantages compared with conventional therapies. This systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to evaluate the effectiveness and safety of moxibustion therapy for insomnia. METHODS: We conducted a comprehensive literature review of the CENTRAL, PubMed, EMBASE, Web of science, CNKI, VIP, and Wanfang Data databases from their inception to July 2015 for RCTs that compared moxibustion with western medications, oral Chinese medicine, or other methods of traditional Chinese medicine (TCM) in patients with primary insomnia. The primary outcome measure was effective rate and secondary outcome measure was adverse events. Data collection and analysis included risk of bias evaluation, meta-analysis, sensitivity analysis, publication bias and adverse events analysis according to corresponding criteria. RESULTS: The study included 22 RCTs (1,971 patients). The quality of the studies was low. The overall meta-analysis demonstrated that moxibustion was more effective for insomnia than western medications, oral Chinese medicine and other TCM therapies (RR = 1.17, 95 % CI 1.12 to 1.23, P < 0.00001). Subgroup analyses demonstrated that moxibustion was more effective for insomnia than western medications (RR = 1.16, 95 % CI 1.09 to 1.24, P < 0.00001), oral Chinese medicine (RR = 1.11, 95 % CI 1.04 to 1.18, P = 0.002), and other TCM therapies (RR = 1.22, 95 % CI 1.15 to 1.30, P < 0.00001). There were no serious adverse effects associated with moxibustion therapy for insomnia, and the rate of adverse events was low. CONCLUSION: It is difficult to get the conclusion regarding the effectiveness and safety of moxibustion for primary insomnia due to insufficient evidence, such as the high risk of bias in the included studies, small sample sizes, and few reports on adverse effects. Moxibustion should be considered as a novel therapeutic option for insomnia, and more rigorous clinical trials of moxibustion therapy for insomnia are needed to assess its effects.


Asunto(s)
Moxibustión , Trastornos del Inicio y del Mantenimiento del Sueño/terapia , Adulto , Anciano , Femenino , Humanos , Masculino , Medicina Tradicional China , Persona de Mediana Edad , Moxibustión/efectos adversos , Moxibustión/métodos , Moxibustión/normas
9.
Pak J Pharm Sci ; 29(3 Suppl): 1011-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27383493

RESUMEN

The stability of meridian detector was the basis to study meridian through conductance method. Ancient documents mentioned that the human body's blood could change with the time and meridians. When qi and blood came, the qi and blood would be full of that place; when qi and blood gone, the local skin shining could fade and recess. It liked the tidal fluctuation, then caused the corresponding acupuncture points conductance value changes. Modern studies had reported that meridian detector instrument the skin area of twelve meridians acupuncture points could change along with time within 24 hours. In this circumstance, whether the conductance values changes in human acupuncture points had statistical significance was vital important. DMS meridian detector instruction was adopt to measure the twelve meridian jingyuan acupuncture point in order to analyze the acupuncture point conductance value changes within one day.


Asunto(s)
Puntos de Acupuntura , Terapia por Acupuntura/instrumentación , Meridianos , Piel , Terapia por Acupuntura/métodos , Adolescente , Adulto , Conductividad Eléctrica , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Factores de Tiempo , Adulto Joven
10.
ScientificWorldJournal ; 2015: 148948, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26495415

RESUMEN

BACKGROUND: In this study, we use association rules to explore the latent rules and patterns of prescribing and adjusting the ingredients of herbal decoctions based on empirical herbal formula of Chinese Medicine (CM). MATERIALS AND METHODS: The consideration and development of CM prescriptions based on the knowledge of CM doctors are analyzed. The study contained three stages. The first stage is to identify the chief symptoms to a specific empirical herbal formula, which can serve as the key indication for herb addition and cancellation. The second stage is to conduct a case study on the empirical CM herbal formula for insomnia. Doctors will add extra ingredients or cancel some of them by CM syndrome diagnosis. The last stage of the study is to divide the observed cases into the effective group and ineffective group based on the assessed clinical effect by doctors. The patterns during the diagnosis and treatment are selected by the applied algorithm and the relations between clinical symptoms or indications and herb choosing principles will be selected by the association rules algorithm. RESULTS: Totally 40 patients were observed in this study: 28 patients were considered effective after treatment and the remaining 12 were ineffective. 206 patterns related to clinical indications of Chinese Medicine were checked and screened with each observed case. In the analysis of the effective group, we used the algorithm of association rules to select combinations between 28 herbal adjustment strategies of the empirical herbal formula and the 190 patterns of individual clinical manifestations. During this stage, 11 common patterns were eliminated and 5 major symptoms for insomnia remained. 12 association rules were identified which included 5 herbal adjustment strategies. CONCLUSION: The association rules method is an effective algorithm to explore the latent relations between clinical indications and herbal adjustment strategies for the study on empirical herbal formulas.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional China , Pautas de la Práctica en Medicina , Demografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
11.
ACS Appl Mater Interfaces ; 16(22): 28570-28577, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38769608

RESUMEN

Despite being heralded as the "holy grail" of anodes for their high theoretical specific capacity, lithium (Li) metal anodes still face practical challenges due to difficulties in fabricating ultrathin Li with controllable thickness and suppressing Li dendrites growth. Herein, we introduce a simple and cost-effective dip-coating method to fabricate ultrathin lithium-tin (LiSn) anode with adjustable thicknesses ranging from 4.5 to 45 µm. The in situ formation of Li22Sn5 alloy improves the wettability of the molten Li, enabling the casting of ultrathin Li metal layers on different substrates. More importantly, the abundant Li22Sn5 lithiophilic sites significantly lower the nucleation overpotential, inducing uniform Li deposition and accelerating the electrochemical reaction at the interface. As a result, the symmetric cell assembled with LiSn-Cu electrodes can cycle stably for more than 120 h with a charge/discharge depth of 50%, which is 1.5 times longer than the lifespan of the pure Li anode. In the full cells paired with NCM cathode, the discharge specific capacity is improved from 13.84 to 70.31 mA h g-1 with the LiSn-Cu anode at 8 C. The LiSn-Cu||NCM full cell realized a high energy density of 724.9 Wh kg-1 at the active material level with an N/P ratio of 1.4.

12.
Opt Express ; 21(5): 5654-70, 2013 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-23482139

RESUMEN

We simultaneously investigate the four-wave mixing and the fluorescence signals via two cascade electromagnetically induced transparency (EIT) systems in atomic rubidium vapor. By manipulating the deflection angle between the probe beam and certain coupling beams, the dark state can extraordinarily switch to bright state, induced by the angle-modulation on the dressing effect. Besides, in the fluorescence signal, the peak of two-photon fluorescence due to classical emission and the dip of single-photon fluorescence due to dressing effect are distinguished, both in separate spectral curves and in the global profile of spectrum. Meanwhile, we observe and analyze the similarities and discrepancies between the two ground-state hyperfine levels F = 2 and F = 3 of Rb 85 for the first time.

13.
Zhonghua Zhong Liu Za Zhi ; 35(8): 590-4, 2013 Aug.
Artículo en Zh | MEDLINE | ID: mdl-24314216

RESUMEN

OBJECTIVE: To study the expression of miRNA-106a gene in esophageal squamous cell carcinoma (ESCC) and its association with clinicopathological features and prognosis of ESCC patients. METHODS: Real-time fluorescence quantitative polymerase chain reaction (PCR) assay was used to determine the expression of miRNA-106a gene in esophageal cancer tissue and corresponding normal mucosa of 81 cases. Immunohistochemical technique was applied to detect the expression of p53, human epidermal growth factor receptor 2 (HER-2), DNA topoisomerase II (Topo II) and multidrug resistance-associated protein (MRP). The association of miRNA-106a expression with clinicopathological features, expression of related proteins, and prognosis of the patients was analyzed. RESULTS: Among the 81 cases, under-expression of miRNA-106a gene was found in 48 cases (59.3%), normal expression in 22 cases (27.2%), and overexpression in 11 cases (13.6%). The expression of miRNA-106 gene was significantly associated with lymph node metastasis, pathological stage, and nerve invasion (all P < 0.05), significantly associated with expression of p53 (P = 0.006), and not significantly associated with expressions of HER-2, Topo II and MRP proteins (all P > 0.05). The expression of miRNA-106a gene was also significantly associated with progression-free survival (PFS, P = 0.032), but not significantly with overall survival (OS, P = 0.486). The results of Cox multivariate regression analysis showed that the PFS of ESCC patients was significantly correlated with lymph node metastasis (P = 0.029), but not correlated with the age, gender, tumor length, T stage, degree of differentiation, nerve invasion, and miRNA-106a expression (all P > 0.05). CONCLUSIONS: In esophageal squamous cell carcinomas, the miRNA-106a gene is under-expressed, with tumor suppressor function, and may be regarded as a biological marker to assess the prognosis in patients with esophageal squamous cell carcinoma.


Asunto(s)
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , MicroARNs/metabolismo , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , ADN-Topoisomerasas de Tipo II/metabolismo , Supervivencia sin Enfermedad , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago , Femenino , Humanos , Inmunohistoquímica , Metástasis Linfática , Masculino , Persona de Mediana Edad , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Invasividad Neoplásica , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor ErbB-2/metabolismo , Tasa de Supervivencia , Proteína p53 Supresora de Tumor/metabolismo
14.
Prog Orthod ; 24(1): 38, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37981597

RESUMEN

OBJECTIVES: To investigate the displacement of dentition and stress distribution on periodontal ligament (PDL) during retraction and intrusion of anterior teeth under different proclination of incisors using clear aligner (CA) in cases involving extraction of the first premolars. METHODS: Models were constructed, consisting of the maxilla, PDLs, CA and maxillary dentition without first premolars. These models were then imported to finite element analysis (FEA) software. The incisor proclination determined the division of the models into three groups: Small torque (ST) with U1-SN = 100°, Middle torque (MT) with U1-SN = 110°, and High torque (HT) with U1-SN = 120°. Following space closure, a 200 g intrusion force was applied at angles of 60°, 70°, 80°, and 90° to the occlusal plane, respectively. RESULTS: CA therapy caused lingual tipping and extrusion of incisors, mesial tipping and intrusion of canines, and mesial tipping of posterior teeth in each group. As the proclination of incisors increased, the incisors presented more extrusion and minor retraction, and the teeth from the canine to the second molar displayed an increased tendency of intrusion. The peak Von Mises equivalent stress (VMES) value successively decreased from the central incisor to the canine and from the second premolar to the second molar, and the VMES of the second molar was the lowest among the three groups. When the angle between the intrusion force and occlusal plane got larger, the incisors exhibited greater intrusion but minor retraction. CONCLUSIONS: The "roller coaster effect" usually occurred in cases involving premolar extraction with CA, especially in patients with protruded incisors. The force closer to the vertical direction were more effective in achieving incisor intrusion. The stress on PDLs mainly concentrated on the cervix and apex of incisors during the retraction process, indicating a possibility of root resorption.


Asunto(s)
Aparatos Ortodóncicos Removibles , Ligamento Periodontal , Femenino , Humanos , Incisivo , Análisis de Elementos Finitos , Diente Molar
15.
J Phys Chem Lett ; 14(5): 1198-1207, 2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36715699

RESUMEN

Kinetic quantum sieving (KQS) based on pore size and chemical affinity quantum sieving (CAQS) based on adsorption site are two routes of porous materials to separate hydrogen isotope mixtures. Alkali earth metals (Be, Mg, and Ca) were doped into UiO-67 to explore whether these metal sites can promote H2/D2 separation. Based on the zero-point energy and adsorption enthalpy calculated by density functional theory calculations, the Be dopant shows better H2/D2 separation performance than other alkali earth metal dopants and unsaturated metal sites in metal-organic frameworks based on CAQS. Orbital interaction strongly relates to the chemical affinity and further influences the D2/H2 selectivity. Moreover, the predicted D2/H2 selectivity of Be-doped sites (49.4) at 77 K is even larger than the best experimental result (26). Finally, the different dynamic behaviors of H2 and D2 on Be-doped UiO-67 indicate its strong H2/D2 separation performance via KQS.

16.
Nat Commun ; 14(1): 1735, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36977714

RESUMEN

The ultrafast transport of adsorbates in confined spaces is a goal pursued by scientists. However, diffusion will be generally slower in nano-channels, as confined spaces inhibit motion. Here we show that the movement of long-chain molecules increase with a decrease in pore size, indicating that confined spaces promote transport. Inspired by a hyperloop running on a railway, we established a superfast pathway for molecules in zeolites with nano-channels. Rapid diffusion is achieved when the long-chain molecules keep moving linearly, as well as when they run along the center of the channel, while this phenomenon do not exist for short-chain molecules. This hyperloop-like diffusion is unique for long-chain molecules in a confined space and is further verified by diffusion experiments. These results offer special insights into molecule diffusion under confinement, providing a reference for the selection of efficient catalysts with rapid transport in the industrial field.

17.
J Thorac Dis ; 14(4): 1183-1192, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35572911

RESUMEN

Background: Many studies have reported potential benefits of percutaneous coronary intervention (PCI) versus optimal drug therapy (ODT) for patients with stable coronary heart disease but with inconsistent results. To examine this, an explicit systematic review and meta-analysis was conducted to compared the clinical outcomes of PCI and ODT in these patients. Methods: The following terms were combined to search relative articles through databases PubMed, Cochrane Central Register of Controlled Trials, Embase, and Web of Science published from January 2010 to November 2021 according to Participants, Intervention, Control, Outcomes, Study (PICOS) criteria: "coronary heart disease", "stable coronary heart disease", "stable angina pectoris", "percutaneous coronary intervention", "PCI", "percutaneous transluminal coronary angioplasty", "drug therapy", "optimized drug treatment", and "optimized drug therapy". The meta-analysis was performed by RevMan 5.2, and the Cochrane risk of bias tool was used to evaluate the quality of the included studies. Results: A total of 12 articles were included in the final analysis. There were 4,288 cases of PCI patients and 4,261 cases of ODT patients. The results showed that, when comparing PCI with ODT, there was a significant difference in the probability of myocardial infarction [relative risk (RR) =0.63; 95% confidence intervals (CI): 0.45-0.90] and the patient mortality (RR =0.51; 95% CI: 0.40-0.64). However, there was no significant difference in the prevalence of stroke (RR =1.33; 95% CI: 0.82-2.17), revascularization (RR =0.86; 95% CI: 0.46-1.62) and patient quality of life (MD =10.44; 95% CI: -1.84 to 22.73). Performance bias and detection bias were all unclear in the included studies and should be warned. Discussion: Compared with ODT, PCI reduced the mortality and myocardial infarction rate of patients with CTO or severe coronary artery stenosis. However, the incidence of stroke, revascularization, and quality of life of patients were not significant different between PCI and ODT. Performance bias and detection bias should be cautioned.

18.
J Phys Chem Lett ; 13(12): 2808-2813, 2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35319210

RESUMEN

Effective contact and collision between reactants and active sites are essential for heterogeneous catalysis. Herein, we investigated molecular diffusion in more than 200 kinds of zeolites, and an intriguing "diffusive skin effect" was observed, whereby molecules migrated along the pore walls of zeolites (i.e., diffusion trajectories) because of the effect of the guest-host interaction and diffusion barrier. Furthermore, it was found that such a "diffusive skin effect" of zeolites would strongly promote the contacts and collisions between reactants and active sites in the reaction process, which might effectively promote the zeolite-catalyzed performance. These new findings will provide some new fundamental understanding of zeolite catalytic mechanisms under confinement effect.

19.
Natl Sci Rev ; 9(9): nwac151, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36168443

RESUMEN

Establishing a comprehensive understanding of the dynamical multiscale diffusion and reaction process is crucial for zeolite shape-selective catalysis and is urgently demanded in academia and industry. So far, diffusion and reaction for methanol and dimethyl ether (DME) conversions have usually been studied separately and focused on a single scale. Herein, we decipher the dynamical molecular diffusion and reaction process for methanol and DME conversions within the zeolite material evolving with time, at multiple scales, from the scale of molecules to single catalyst crystal and catalyst ensemble. Microscopic intracrystalline diffusivity is successfully decoupled from the macroscopic experiments and verified by molecular dynamics simulation. Spatiotemporal analyses of the confined carbonaceous species allow us to track the migratory reaction fronts in a single catalyst crystal and the catalyst ensemble. The constrained diffusion of DME relative to methanol alleviates the high local chemical potential of the reactant by attenuating its local enrichment, enhancing the utilization efficiency of the inner active sites of the catalyst crystal. In this context, the dynamical cross-talk behaviors of material, diffusion and reaction occurring at multiple scales is uncovered. Zeolite catalysis not only reflects the reaction characteristics of heterogeneous catalysis, but also provides enhanced, moderate or suppressed local reaction kinetics through the special catalytic micro-environment, which leads to the heterogeneity of diffusion and reaction at multiple scales, thereby realizing efficient and shape-selective catalysis.

20.
Patient Prefer Adherence ; 16: 1875-1884, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35942226

RESUMEN

Background: Body constitution is a fundamental concept in traditional Chinese medicine (TCM) for clinical diagnosis, treatment of illness, and community-based health promotion. Clinical assessment of patients' body constitutions, however, has never been easy and consistent, even by well-trained clinicians and TCM practitioners. Therefore, questionnaires such as the popular Constitution in Chinese Medicine Questionnaire (CCMQ) can be an appealing and convenient assessment alternative. The present research borrowed advanced methodologies for questionnaire development in psychology and other social sciences to examine the performance of the CCMQ in terms of (i) the strength of relations of each item with its designated constitution, (ii) the reliabilities of each constitution, and (iii) the overall 9-constitution structure. This research provided empirical evidence to support the use of the CCMQ and proposed directions for refinement in future revisions of the CCMQ or similar measures. Methods: A total of 1571 volunteers from three villages in southern China participated in the CCMQ survey. The item characteristics, reliabilities, interconstitution correlations, and confirmatory factor analysis of the 9-body-constitution structure were examined. Results: The results generally supported the appropriateness of the clinical observations (the questionnaire items) and the CCMQ 9-constitution classification structure. Nevertheless, some relatively weaker items, item pairs with similar meanings, and highly overlapping constitutions were identified for future CCMQ revisions. Conclusion: The CCMQ measured the 9 constitutions efficiently and with reasonably good reliability and construct validity. Given the various challenges to assessing TCM body constitutions even by experienced clinicians, the CCMQ provides an appealing alternative to measure the Chinese body constitutions of healthy participants in large-scale research or community health promotion programs. The present study also demonstrated how advanced methodologies in social sciences can help validate and refine the CCMQ and similar complementary medicine measures.

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