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3.
Small ; 19(27): e2207858, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36949014

RESUMEN

Electrodes are indispensable components in semiconductor devices, and now are mainly made from metals, which are convenient for use but not ideal for emerging technologies such as bioelectronics, flexible electronics, or transparent electronics. Here the methodology of fabricating novel electrodes for semiconductor devices using organic semiconductors (OSCs) is proposed and demonstrated. It is shown that polymer semiconductors can be heavily p- or n-doped to achieve sufficiently high conductivity for electrodes. In contrast with metals, the doped OSC films (DOSCFs) are solution-processable, mechanically flexible, and have interesting optoelectronic properties. By integrating the DOSCFs with semiconductors through van der Waals contacts different kinds of semiconductor devices can be constructed. Importantly, these devices exhibit higher performance than their counterparts with metal electrodes, and/or excellent mechanical or optical properties that are unavailable in metal-electrode devices, suggesting the superiority of DOSCF electrodes. Given the existing large amount of OSCs, the established methodology can provide abundant electrode choices to meet the demand of various emerging devices.

4.
BMC Med ; 20(1): 148, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-35422042

RESUMEN

BACKGROUND: Ketone body ß-hydroxybutyrate (BHB) has received more and more attentions, because it possesses a lot of beneficial, life-preserving effects in the fields of clinical science and medicine. However, the role of BHB in intestinal inflammation has not yet been investigated. METHODS: Colonic mucosa of inflammatory bowel disease (IBD) patients and healthy controls were collected for evaluation of BHB level. Besides, the therapeutic effect of exogenous BHB in a murine model of acute dextran sulfate sodium (DSS)-induced colitis were assessed by body weight change, colon length, disease activity index, and histopathological sections. The regulatory effectors of BHB were analyzed by RT-qPCR, immunofluorescence, and microbe analysis in vivo. Moreover, the molecular mechanism of BHB was further verified in bone marrow-derived macrophages (BMDMs). RESULTS: In this study, significantly reduced BHB levels were found in the colonic mucosa from IBD patients and correlated with IBD activity index. In addition, we demonstrated that the administration of exogenous BHB alleviated the severity of acute experimental colitis, which was characterized by less weight loss, disease activity index, colon shortening, and histology scores, as well as decreased crypt loss and epithelium damage. Furthermore, BHB resulted in significantly increased colonic expression of M2 macrophage-associated genes, including IL-4Ra, IL-10, arginase 1 (Arg-1), and chitinase-like protein 3, following DSS exposure, suggesting an increased M2 macrophage skewing in vivo. Moreover, an in vitro experiment revealed that the addition of BHB directly promoted STAT6 phosphorylation and M2 macrophage-specific gene expression in IL-4-stimulated macrophages. Besides, we found that BHB obviously increased M2 macrophage-induced mucosal repair through promoting intestinal epithelial proliferation. However, the enhancement effect of BHB on M2 macrophage-induced mucosal repair and anti-inflammation was completely inhibited by the STAT6 inhibitor AS1517499. CONCLUSIONS: In summary, we show that BHB promotes M2 macrophage polarization through the STAT6-dependent signaling pathway, which contributes to the resolution of intestinal inflammation and the repair of damaged intestinal tissues. Our finding suggests that exogenous BHB supplement may be a useful therapeutic approach for IBD treatment.


Asunto(s)
Colitis , Enfermedades Inflamatorias del Intestino , Ácido 3-Hidroxibutírico/metabolismo , Ácido 3-Hidroxibutírico/farmacología , Ácido 3-Hidroxibutírico/uso terapéutico , Animales , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/metabolismo , Sulfato de Dextran/efectos adversos , Sulfato de Dextran/metabolismo , Modelos Animales de Enfermedad , Humanos , Inflamación/metabolismo , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Macrófagos , Ratones , Ratones Endogámicos C57BL , Factor de Transcripción STAT6/metabolismo , Factor de Transcripción STAT6/farmacología , Transducción de Señal
5.
Small ; 18(15): e2106716, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35218141

RESUMEN

Herein, a type of hypervalent iodine compound-iodosobenzene (PhIO)-is proposed to regulate the LiPSs electrochemistry and enhance the performance of Li-S battery. PhIO owns the practical advantages of low-cost, commercial availability, environmental friendliness and chemical stability. The lone pair electrons of oxygen atoms in PhIO play a critical role in forming a strong Lewis acid-base interaction with terminal Li in LiPSs. Moreover, the commercial PhIO can be easily converted to nanoparticles (≈20 nm) and uniformly loaded on a carbon nanotube (CNT) scaffold, ensuring sufficient chemisorption for LiPSs. The integrated functional PhIO@CNT interlayer affords a LiPSs-concentrated shield that not only strongly obstructs the LiPSs penetration but also significantly enhances the electrolyte wettability and Li+ conduction. The PhIO@CNT interlayer also serves as a "vice current collector" to accommodate various LiPSs and render smooth LiPSs transformation, which suppresses insulating Li2 S2 /Li2 S layer formation and facilitates Li+ diffusion. The Li-S battery based on PhIO@CNT interlayer (6 wt% PhIO) exhibits stable cycling over 1000 cycles (0.033% capacity decay per cycle) and excellent rate performance (686.6 mAh g-1 at 3 C). This work demonstrates the great potential of PhIO in regulating LiPSs and provides a new avenue towards the low-cost and sustainable application of Li-S batteries.

6.
Nat Commun ; 12(1): 5723, 2021 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-34588457

RESUMEN

Doping has been widely used to control the charge carrier concentration in organic semiconductors. However, in conjugated polymers, n-doping is often limited by the tradeoff between doping efficiency and charge carrier mobilities, since dopants often randomly distribute within polymers, leading to significant structural and energetic disorder. Here, we screen a large number of polymer building block combinations and explore the possibility of designing n-type conjugated polymers with good tolerance to dopant-induced disorder. We show that a carefully designed conjugated polymer with a single dominant planar backbone conformation, high torsional barrier at each dihedral angle, and zigzag backbone curvature is highly dopable and can tolerate dopant-induced disorder. With these features, the designed diketopyrrolopyrrole (DPP)-based polymer can be efficiently n-doped and exhibit high n-type electrical conductivities over 120 S cm-1, much higher than the reference polymers with similar chemical structures. This work provides a polymer design concept for highly dopable and highly conductive polymeric semiconductors.

7.
Int J Equity Health ; 20(1): 198, 2021 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-34461910

RESUMEN

BACKGROUND: The goal of this paper was to assess the quality of primary healthcare services at community health centres (CHCs) from the demand (patient) and supplier (healthcare service institution) angles. METHODS: This study was conducted at six CHCs in the Greater Bay Area of China. Between August and October 2019, 1,568 patients were recruited (55.8% women and 44.2% men). We evaluated the service quality of CHCs using the National Committee for Quality Assurance Patient-Centred Medical Home (NCQA-PCMH) recognition questionnaire. We assessed patients' experiences with medical and health services using the Primary Care Assessment Tools (PCAT). RESULTS: PCAT total and sub-domains scores were significantly difference at the six CHCs (P < 0.001). Among the six CHCs, Shayuan CHC had the highest PCAT total and sub-domain scores and the highest NCQA-PCMH total and sub-domain scores, as well. Older (> 60 years), female, lower education, and employee medical-insured individuals had better patient experiences. CONCLUSIONS: Our results indicate that CHCs could improve their service quality by improving both institutional health service quality based on NCQA-PCMH assessment and patient experiences based on PCAT scales. These findings can help inform patient-centred primary healthcare policy and management.


Asunto(s)
Centros Comunitarios de Salud , Satisfacción del Paciente , Atención Primaria de Salud , Calidad de la Atención de Salud , Adolescente , Adulto , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente/estadística & datos numéricos , Atención Primaria de Salud/normas , Calidad de la Atención de Salud/estadística & datos numéricos , Factores Socioeconómicos , Adulto Joven
8.
Curr Med Imaging ; 17(11): 1363-1368, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33632109

RESUMEN

BACKGROUND: Portal vein velocity (PVV) has shown a reasonable correlation with the presence of portal hypertension in patients with cirrhosis. This study aims to evaluate the value of PVV for diagnosing clinically significant portal hypertension (CSPH) and predicting the risk of variceal hemorrhage (VH) in patients with hepatitis B virus (HBV)-related cirrhosis. MATERIALS AND METHODS: A cohort of 166 consecutive adult patients with HBV-related cirrhosis was recruited in this retrospective study from two high-volume liver centers in China between April 2015 and April 2017. The performance of PVV and other non-invasive parameters for diagnosing CSPH and predicting the risk of VH was studied. RESULTS: PVV demonstrated the best performance for diagnosing CSPH (defined as an HVPG ≥10 mmHg) in patients with HBV-related cirrhosis among the included non-invasive predictors with the area under the receiver operating characteristic curve (AUC), specificity, and sensitivity of 0.745, 50%, and 93.5%, respectively. Other non-invasive markers, including APRI, AAR, LS, FIB-4, and diameter of the portal vein, did not show sufficient performance with the AUCs of 0.565, 0.560, 0.544, 0.529, and 0.474, respectively. With regard to predicting the risk of VH (defined as an HVPG ≥12 mmHg), PPV also exhibited a moderate performance with an AUC of 0.762, which was superior to that of the aforementioned markers. By using two cutoff values of PVV to rule-out (11.65 cm/s) and rule-in (20.20 cm/s) CSPH, 30 (33.7%) patients showed definite results categories, with 23 (76.7%) patients were well classified and 7 (23.3%) were misclassified. Fifty-nine (66.3%) patients were with indeterminate results. By using PVV values of 13.10 cm/s and 21.40 cm/s to rule-out and rule-in HVPG ≥ 12mmHg, 34 (38.2%) patients has definite results, among whom 26 (76.5%) were well classified and 8 (23.5%) were misclassified. And 55 (61.8%) patients required further evaluation. CONCLUSION: PPV is insufficient to serve as a non-invasive parameter for identifying CSPH and predicting the risk of VH in patients with HBV-related cirrhosis.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Várices Esofágicas y Gástricas , Hipertensión Portal , Adulto , Hemorragia Gastrointestinal , Virus de la Hepatitis B , Humanos , Hipertensión Portal/diagnóstico , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Vena Porta , Estudios Retrospectivos
9.
Angew Chem Int Ed Engl ; 60(15): 8189-8197, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33403799

RESUMEN

Doping of polymeric semiconductors limits the miscibility between polymers and dopants. Although significant efforts have been devoted to enhancing miscibility through chemical modification, the electrical conductivities of n-doped polymeric semiconductors are usually below 10 S cm-1 . We report a different approach to overcome the miscibility issue by modulating the solution-state aggregates of conjugated polymers. We found that the solution-state aggregates of conjugated polymers not only changed with solvent and temperature but also changed with solution aging time. Modulating the solution-state polymer aggregates can directly influence their solid-state microstructures and miscibility with dopants. As a result, both high doping efficiency and high charge-carrier mobility were simultaneously obtained. The n-doped electrical conductivity of P(PzDPP-CT2) can be tuned up to 32.1 S cm-1 . This method can also be used to improve the doping efficiency of other polymer systems (e.g. N2200) with different aggregation tendencies and behaviors.

10.
Ann Transl Med ; 7(20): 586, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31807567

RESUMEN

BACKGROUND: Acute variceal bleeding is one of the critical complications in patients with liver cirrhosis. Severe renal vasoconstriction in consequence of low peripheral vascular resistance triggers the reduction of glomerular filtration rate (GFR), and thus induces acute kidney injury (AKI)/hepato-renal syndrome (HRS). Terlipressin and octreotide have been used in the management of cirrhotic patients with variceal bleeding. Also, terlipressin has been recommended as the international first-line pharmacological therapy for the treatment of HRS. In addition, the use of renal functional magnetic resonance imaging (fMRI) has become increasingly prevalent in research and clinical applications. However, the renal function-protective effect of terlipressin and octreotide and the value of fMRI in monitoring renal function remains unclear in patients with cirrhosis undergoing acute variceal bleeding. METHODS: This is a multicenter, randomized controlled trial (RCT). Participants will be 1:1 assigned randomly into either terlipressin or octreotide groups. Sixty participants with clinically and/or pathologically diagnosed cirrhosis and active gastroesophageal variceal bleeding (GVB) will be recruited in several sites in China. Participants will receive either the treatment of terlipressin or octreotide after assigned into each group. The primary end point for the trial is the renal function. The secondary end points are (I) renal perfusion; (II) renal blood oxygenation; (III) failure to control bleeding; (IV) intra-hospital rebleeding; (V) intra-hospital mortality; (VI) adverse events (AE); (VII) overall survival. Statistical analysis including multivariate Cox regression, Kaplan-Meier analysis with log-rank test, etc. will be conducted. DISCUSSION: The study will provide new insight into the protection of renal function in the process of the treatment of variceal bleeding in patients with cirrhosis. TRIAL REGISTRATION NUMBER: NCT04028323.

11.
J Am Chem Soc ; 141(51): 20215-20221, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31774667

RESUMEN

n-Doped conjugated polymers usually show low electrical conductivities and low thermoelectric power factors, limiting their applications in n-type organic thermoelectrics. Here, we report the synthesis of a new diketopyrrolopyrrole (DPP) derivative, pyrazine-flanked DPP (PzDPP), with the deepest LUMO level in all the reported DPP derivatives. Based on PzDPP, a donor-acceptor copolymer, P(PzDPP-CT2), is synthesized. The polymer displays a deep LUMO energy level and strong interchain interaction with a short π-π stacking distance of 3.38 Å. When doped with n-dopant N-DMBI, P(PzDPP-CT2) exhibits high n-type electrical conductivities of up to 8.4 S cm-1 and power factors of up to 57.3 µW m-1 K-2. These values are much higher than previously reported n-doped DPP polymers, and the power factor also ranks the highest in solution-processable n-doped conjugated polymers. These results suggest that PzDPP is a promising high-performance building block for n-type organic thermoelectrics and also highlight that, without sacrificing polymer interchain interactions, efficient n-doping can be realized in conjugated polymers with careful molecular engineering.

12.
BMJ Open ; 9(8): e025656, 2019 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-31473610

RESUMEN

OBJECTIVE: This meta-analysis was performed to investigate the correlation between von Willebrand factor (vWF) antigen and hepatic venous pressure gradient (HVPG) and to evaluate the diagnostic performance of vWF to detect clinically significant portal hypertension (CSPH) and severe portal hypertension (SPH). DESIGN: Systematic review and meta-analysis. METHODS: MEDLINE, EMBASE, Web of Science and the Cochrane Library were screened up to 5 April 2018. Studies related to the diagnostic performance of vWF to detect CSPH and/or SPH with HVPG as the reference standard were included. Study quality was assessed by using the Quality Assessment of Diagnostic Accuracy Studies scale. Two authors independently used a standardised form to extract data. OUTCOMES: The primary outcome was the correlation coefficient between vWF and HVPG. The secondary outcome was the diagnostic performance of vWF to detect CSPH or SPH. RESULTS: A total of six articles involving 994 patients were included in this study. Five of the included articles were used to stratify the results for the correlation coefficient, three for the diagnostic performance of CSPH and two for SPH. The pooled correlation coefficient based on the random effects model was 0.54 (95% CI 0.35 to 0.69), thus suggesting a moderate correlation between vWF and HVPG. The pooled sensitivity, specificity and area under the curve of vWF for CSPH detection were 82% (95% CI 78 to 86), 76% (95% CI 68 to 83) and 0.87 (95% CI 0.80 to 0.94), respectively. Regarding the ability of vWF to detect SPH, the pooled sensitivity and specificity were 86% (95% CI 80 to 90) and 75% (95% CI 66 to 83), respectively. These results supported the satisfactory diagnostic performance of vWF for CSPH and SPH detection. CONCLUSIONS: vWF, as a novel biomarker, has a moderate correlation with HVPG and shows a satisfactory performance for the diagnosis of CSPH and SPH in patients with cirrhosis.


Asunto(s)
Hipertensión Portal/diagnóstico , Factor de von Willebrand/análisis , Biomarcadores/sangre , Humanos , Hipertensión Portal/sangre , Índice de Severidad de la Enfermedad
14.
Ann Transl Med ; 7(23): 717, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32042733

RESUMEN

BACKGROUND: We aimed to compare the efficacy of different drugs facilitating endoscopy in patients with acute variceal bleeding. METHODS: Databases were searched to identify randomized controlled trials which compared the efficacy of vasoactive drugs (vasopressin, terlipressin, octreotide, somatostatin) with placebo or each other. The primary outcomes were 6-week and 5-day mortality. Secondary outcomes were 5-day rebleeding, control of initial bleeding and adverse events. Pairwise and network meta-analysis were performed. RESULTS: We identified 14 RCTs involved 2,187 patients. Four drugs had comparable clinical efficacy in all involving outcomes, except for adverse events. However, we do exhibit a superiority when vasopressin (OR, 4.40; 95% CI: 1.04-19.57), terlipressin (OR, 4.58; 95% CI: 1.63-13.63), octreotide (OR, 5.79; 95% CI: 2.41-16.71) and somatostatin (OR, 5.15; 95% CI: 1.40-27.39) were compared to placebo respectively as for initial hemostasis. In addition, only octreotide was more effective than placebo in decreasing 5-day rebleeding (OR, 0.44; 95% CI: 0.22-0.90). Meanwhile, octreotide was shown to have the highest probability ranking the best to improve initial hemostasis (mean rank =1.8) and carries a lowest risk of adverse events (9.1%) and serious adverse events (0.0%) compared to other drugs. CONCLUSIONS: Balanced with curative effect and tolerability, octreotide may be the preferred vasoactive drug facilitating endoscopy.

15.
Angew Chem Int Ed Engl ; 57(29): 8947-8952, 2018 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-29756408

RESUMEN

Commercially available [Ph3 C][B(C6 F5 )4 ] served as a highly efficient metal-free and single-component initiator not only for the carbocationic polymerization of polar and bulky aryl isocyanides with extremely high activity up to 1.2×107  g of polymer/(molcat. h), but also for the helical-sense-selective polymerization of chiral aryl isocyanides and copolymerization with achiral aryl isocyanides to afford high-molecular-weight functional poly(aryl isocyanide)s with good solubility as well as AIE characteristics and/or a single-handed helical conformation.

16.
Macromol Rapid Commun ; 39(8): e1800002, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29504174

RESUMEN

Chromium-based metal-organic framework (MOF) Cr-MIL-100/101 activated by activator and aluminum trialkyl compound serve as unique, highly efficient heterogeneous single-site catalysts for the controlled polymerization of isoprene, which not only exhibit quasi-living nature in isoprene polymerization but also unprecedentedly switch from cyclic to cis-1,4-selectivity depending on the activator used to yield low molecular weight cyclic PIPs or extremely high molecular weight cis-1,4-PIPs. Such heterogeneous Cr-MOF catalysts can be recycled approximately five times. Based on nitrogen sorption isotherm tests and powder X-ray diffraction, a cationic mechanism is suggested, in which the polymerization takes place inside the open nanochannels of MOF catalysts and the space confinement effect of narrow open nanochannels originated from the coordination of PhNMe2 from activator [PhNHMe2 ][B(C6 F5 )4 ] with the multiple metal centers of MOF catalysts might give a rational explanation for such controlled adjustment on the PIP's structure and properties.


Asunto(s)
Boratos/química , Butadienos/química , Cromo/química , Hemiterpenos/química , Pentanos/química , Catálisis , Polimerizacion
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