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1.
Hepatol Commun ; 8(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38180960

RESUMEN

BACKGROUND AND AIMS: Acute-on-chronic liver failure (ACLF) is a highly dynamic syndrome. The objective of this study was to delineate the clinical course of patients with HBV-ACLF and to develop a model to estimate the temporal evolution of disease severity. METHODS: We enrolled eligible patients from 2 large, multicenter prospective cohorts. The ACLF grade, organ failures, and outcomes were assessed at multiple time points (days 1/4/7/14/21/28). Probabilities for ACLF transitions between these disease states and to death within 28 days were calculated using a multi-state model that used baseline information and updated ACLF status. The model was validated in independent patients. RESULTS: Among all the 445 patients with HBV-ACLF, 76 represented disease progression, 195 had a stable or fluctuating course, 8 with improvement, and the remaining 166 with resolution within 28-day follow-up. New coagulation (63.64%) or renal failure (45.45%) was frequently observed during early progression. Patients with disease progression had a higher incidence of new episodes of ascites [10 (13.16%) vs. 22 (5.96%), p = 0.027] and HE [13(17.11%) vs. 21 (5.69%), p = 0.001], and a significant increase in white blood cell count. The multi-state model represented dynamic areas under the receiver operating characteristic curves ranging from 0.71 to 0.84 for predicting all ACLF states and death at 4, 7, 14, 21, and 28 days post-enrollment and from 0.73 to 0.94 for predicting death alone, performing better than traditional prognostic scores. CONCLUSIONS: HBV-ACLF is a highly dynamic syndrome with reversibility. The multi-state model is a tool to estimate the temporal evolution of disease severity, which may inform clinical decisions on treatment.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Humanos , Insuficiencia Hepática Crónica Agudizada/diagnóstico , Virus de la Hepatitis B , Estudios Prospectivos , Ascitis , Progresión de la Enfermedad
2.
Small ; 20(10): e2304846, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37910867

RESUMEN

Fast recombination dynamics of photocarriers competing with sluggish surface photohole oxidation kinetics severely restricts the photoelectrochemical (PEC) conversion efficiency of photoanode. Here, a defect engineering strategy is developed to regulate photohole transfer and interfacial injection dynamics of 2D ZnIn2 S4 (ZIS). Via selectively introducing substitutional Cd dopant at Zn sites of the ZIS basal plane, energy band structure and surface electrochemical activity are successfully modulated in the Cd-doped ZIS (Cd-ZIS) nanosheet array photoanode. Comprehensive characterizations manifest that a shallow acceptor level induced by Cd doping and superior electrochemical activity make surface Cd dopants simultaneously act as capture centers and active sites to mediate photohole dynamics at the reaction interface. In depth photocarrier dynamics analysis demonstrates that highly efficient photohole capture of Cd dopants brings about effective space separation of photocarriers and acceleration of surface reaction kinetics. Therefore, the optimum 2D Cd-ZIS achieves excellent PEC solar energy conversion efficiency with a photocurrent density of 5.1 mA cm-2 at 1.23 VRHE and a record of applied bias photon-to-current efficiency (ABPE) of 3.0%. This work sheds light on a microstructure design strategy to effectively regulate photohole dynamics for the next-generation semiconducting PEC photoanodes.

3.
Ann Hepatol ; 28(6): 101147, 2023 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-37643717

RESUMEN

INTRODUCTION AND OBJECTIVES: The relationship between anemia and the outcome of patients with cirrhosis is not completely clear. Therefore, we performed this large-scale epidemiological study to investigate the prevalence and severity of anemia in patients with cirrhosis and acute decompensation or liver injury and how anemia impacts short-term and long-term outcomes. PATIENTS AND METHODS: Patients with cirrhosis and acute decompensation (AD) or acute liver injury (ALI) were enrolled in the Chinese AcuTe on CHronic LIver FailurE (CATCH-LIFE) studies, which consisted of two large, multicenter, prospective, observational cohorts between January 2015 and December 2016 and July 2018 and January 2019. We conducted data analysis on the prevalence of anemia and determined the relationship between anemia and prognosis. RESULTS: Among 1979 patients, 1389 (70.2%) had anemia, among whom 599 (41.3%) had mild anemia, 595 (15.8%) had moderate anemia and 195 (2.4%) had severe anemia. A linear association between hemoglobin level and 90-day or 1-year LT-free mortality was shown, and a 10 g/L decrease in hemoglobin level was associated with a 6.8% extra risk of 90-day death and a 5.7% extra risk of 1-year death. Severe anemia was an independent risk factor for 90-day [HR=1.649 (1.100, 2.473), p=0.016] and 1-year LT-free mortality [HR=1.610 (1.159, 2.238), p=0.005]. Multinomial logistic regression analysis further identified that severe anemia was significantly associated with post-28-day mortality but not within-28-day mortality. CONCLUSIONS: Anemia is common in patients with cirrhosis admitted for acute events. Severe anemia was associated with poor 90-day and 1-year prognoses in these patients.

4.
Front Microbiol ; 13: 1013439, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36569093

RESUMEN

Background: The accurate prediction of the outcome of hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is impeded by population heterogeneity. The study aimed to assess the impact of underlying cirrhosis on the performance of clinical prediction models (CPMs). Methods: Using data from two multicenter, prospective cohorts of patients with HBV-ACLF, the discrimination, calibration, and clinical benefit were assessed for CPMs predicting 28-day and 90-day outcomes in patients with cirrhosis and those without, respectively. Results: A total of 919 patients with HBV-ACLF were identified by Chinese Group on the Study of Severe Hepatitis B (COSSH) criteria, including 675 with cirrhosis and 244 without. COSSH-ACLF IIs, COSSH-ACLFs, Chronic Liver Failure-Consortium Acute-on-Chronic Liver Failure score (CLIF-C ACLFs), Tongji Prognostic Predictor Model score (TPPMs), Model for End-Stage Liver Disease score (MELDs), and MELD-Sodium score (MELD-Nas) were all strong predictors of short-term mortality in patients with HBV-ACLF. In contrast to a high model discriminative capacity in ACLF without cirrhosis, each prognostic model represents a marked decline of C-index, net reclassification index (NRI), and integrated discrimination improvement (IDI) in predicting either 28-day or 90-day prognosis of patients with cirrhosis. The hazard analysis identified largely overlapping risk factors of poor outcomes in both subgroups, while serum bilirubin was specifically associated with short-term mortality in patients with cirrhosis and blood urea nitrogen in patients without cirrhosis. A subgroup analysis in patients with cirrhosis showed a decline of discrimination of CPMS in those with ascites or infections compared to that in those without. Conclusion: Predicting the short-term outcome of HBV-ACLF by CPMs is optimal in patients without cirrhosis but limited in those with cirrhosis, at least partially due to the complicated ascites or infections.

5.
JHEP Rep ; 4(10): 100529, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36052222

RESUMEN

Background & Aims: Pre-acute-on-chronic liver failure (ACLF) is a distinct intermediate stage between acute decompensation (AD) and ACLF. However, identifying patients with pre-ACLF and predicting progression from AD to ACLF is difficult. This study aimed to identify pre-ACLF within 28 days, and to develop and validate a prediction model for ACLF in patients with HBV-related decompensated cirrhosis. Methods: In total, 1,736 patients with HBV-related cirrhosis and AD were enrolled from 2 large-scale, multicenter, prospective cohorts. ACLF occurrence within 28 days, readmission, and 3-month and 1-year outcomes were collected. Results: Among 970 patients with AD without ACLF in the derivation cohort, the 94 (9.6%) patients with pre-ACLF had the highest 3-month and 1-year LT-free mortality (61.6% and 70.9%, respectively), which was comparable to those with ACLF at enrollment (57.1% and 67.1%); the 251 (25.9%) patients with unstable decompensated cirrhosis had mortality rates of 22.4% and 32.1%, respectively; while the 507 (57.9%) patients with stable decompensated cirrhosis had the best outcomes (1-year mortality rate of 2.6%). Through Cox proportional hazard regression, specific precipitants, including hepatitis B flare with HBV reactivation, spontaneous hepatitis B flare with high viral load, superimposed infection on HBV, and bacterial infection, were identified to be significantly associated with ACLF occurrence in the derivation cohort. A model that incorporated precipitants, indicators of systemic inflammation and organ injuries reached a high C-index of 0.90 and 0.86 in derivation and validation cohorts, respectively. The optimal cut-off value (0.22) differentiated high-risk and low-risk patients, with a negative predictive value of 0.95. Conclusions: Three distinct clinical courses of patients with AD are validated in the HBV-etiology population. The precipitants significantly impact on AD-ACLF transition. A model developed by the precipitant-systemic inflammation-organ injury framework could be a useful tool for predicting ACLF occurrence. Clinical trial number: NCT02457637 and NCT03641872. Lay summary: It was previously shown that patients with decompensated cirrhosis could be stratified into 3 groups based on their short-term clinical prognoses. Herein, we showed that this stratification applies to patients who develop cirrhosis as a result of hepatitis B virus infection. We also developed a precipitant-based model (i.e. a model that incorporated information about the exact cause of decompensation) that could predict the likelihood of these patients developing a very severe liver disease called acute-on-chronic liver failure (or ACLF).

6.
Mater Horiz ; 9(4): 1293-1298, 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35191909

RESUMEN

Solid-state cooling technology based on the caloric effects of phase-transition materials has been a research hotspot due to its environmental friendliness and high efficiency, but limited for practical applications due to its narrow working temperature region. Here, we report giant barocaloric effects based on pressure-driven liquid-solid phase transitions in elastic copolymers of ethylene and vinyl acetate. Giant adiabatic temperature changes of up to 29.6/-26.9 K are directly observed under rapid compressions/decompressions of 400 MPa near the liquid-solid phase transition points. Strikingly, since both the solid and the liquid sides can show giant barocaloric effects, a very broad refrigeration temperature region of more than 110 K is achieved in these copolymers. Furthermore, a cooling prototype is designed to demonstrate the potential applications of these liquid/elastic barocaloric materials. Our study sheds light on exploring liquid-solid phase transition materials for the next-generation refrigerators.

7.
Infect Dis Ther ; 10(4): 2323-2331, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34350562

RESUMEN

INTRODUCTION: Hepatitis B virus (HBV) infection is associated with the onset of several major liver diseases. Inactive hepatitis B surface antigen (HBsAg) carriers (IHCs) may be successfully treated with PEGylated interferon-α2b (PEG-IFNα2b)-based antiviral therapy; however, studies on this treatment have been insufficient. In this study, we evaluated the efficacy and safety of PEG-IFNα2b treatment in IHCs. METHODS: Nineteen IHCs were treated with subcutaneous PEG-IFNα2b (180 µg/week) for 48 weeks (treatment group). Patients were followed up for 24 weeks after treatment discontinuation. Twenty untreated control patients were observed for 72 weeks (control group). HBsAg clearance (HBsAg < 0.05 IU/mL), HBsAg seroconversion, and alanine aminotransferase levels were monitored. RESULTS: Of the 19 patients treated with PEG-IFNα2b, 16 showed HBsAg loss (84.2%), and 13 showed HBsAg seroconversion (68.4%) at 72 weeks. All patients in the treatment group exhibited virological response (serum HBV DNA level < 10 IU/mL) at the time of drug withdrawal. In the control group, no patients experienced HBsAg loss during the observational period. There were no serious adverse events during treatment, and the therapy was well tolerated. CONCLUSIONS: Short PEG-IFNα2b therapy in IHCs produced a high functional cure rate and good safety profile, suggesting that PEG-IFNα2b treatment may be the best choice for clinical cure of some IHCs.

8.
Front Med (Lausanne) ; 8: 709884, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34409052

RESUMEN

Importance: Hepatic encephalopathy is a severe complication, and its contribution to clinical adverse outcomes in patients with acute-on-chronic liver diseases from the East is unclear. Objective: We aimed to investigate the impact of hepatic encephalopathy on clinical characteristics and adverse outcomes in prospective and multicenter cohorts of patients with acute-on-chronic liver diseases. Design: We conducted a cohort study of two multicenter prospective cohorts. Setting: China. Participants: Acute-on-chronic liver disease patients with various etiologies. Exposure: The diagnosis and severity of hepatic encephalopathy were assessed using the West Haven scale. Main Outcome Measure: The correlation between clinical adverse outcomes and varying hepatic encephalopathy grades was analyzed in the target patients. Results: A total of 3,949 patients were included, and 340 of them had hepatic encephalopathy. The incidence of hepatic encephalopathy was higher in patients with alcohol consumption (9.90%) than in those with hepatitis B virus infection (6.17%). The incidence of 28- and 90-day adverse outcomes increased progressively from hepatic encephalopathy grades 1-4. Logistic regression analysis revealed that hepatic encephalopathy grades 3 and 4 were independent risk factors for the 28- and 90-day adverse outcome in the fully adjusted model IV. Stratified analyses showed similar results in the different subgroups. Compared to grades 1-2 and patients without hepatic encephalopathy, those with grade 3 hepatic encephalopathy had a significant increase in clinical adverse outcomes, independent of other organ failures. Conclusions and Relevance: Hepatic encephalopathy grades 3-4 were independent risk factors for 28- and 90-day adverse outcomes. Hepatic encephalopathy grade 3 could be used as an indicator of brain failure in patients with acute-on-chronic liver disease.

9.
Infect Dis Ther ; 10(4): 2259-2270, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34309813

RESUMEN

INTRODUCTION: Hepatitis B surface antigen (HBsAg) clearance is the treatment goal for hepatitis B e antigen (HBeAg)-negative patients with chronic hepatitis B (CHB). However, its rate is extremely low with nucleoside (acid) analogues (NAs) monotherapy. Peginterferon could enhance HBsAg clearance. This study aimed to evaluate the efficacy of peginterferon alfa-2b (PegIFNα-2b) in NAs-experienced patients with CHB with negative HBeAg and low HBsAg level. METHODS: HBeAg-negative patients with CHB who had received NAs therapy over 24 weeks with HBsAg < 1500 IU/mL and HBV DNA < 100 IU/mL were enrolled. Patients received either PegIFNα-2b add-on therapy (n = 108) or continuous NAs monotherapy (n = 75). The primary endpoint was HBsAg clearance rate at week 48. RESULTS: At week 48, serum HBV DNA was undetectable among all PegIFNα-2b add-on therapy patients. Almost all patients maintained HBV DNA suppression in the PegIFNα-2b add-on group (100%, 108/108) and NAs monotherapy group (97.33%, 73/75). Only patients with PegIFNα-2b add-on therapy achieved HBsAg clearance (50.93%, 55/108) and HBsAg seroconversion (48.15%, 52/108) at week 48. Patients with baseline HBsAg < 100 IU/mL achieved the highest HBsAg clearance rate and HBsAg seroconversion rate at week 48 (60.87%, 28/46 and 58.70%, 27/46 respectively). HBsAg clearance and HBsAg seroconversion at week 72 had no significant difference with continuing or discontinuing PegIFNα-2b therapy after 48 weeks of treatment. PegIFNα-2b add-on therapy was well tolerated. CONCLUSIONS: PegIFNα-2b add-on therapy increases HBsAg clearance rate and seroconversion rate for HBeAg-negative patients with CHB, particularly for those with lower HBsAg level. It would be unnecessary to prolong PegIFNα-2b duration after 48 weeks of PegIFNα-2b treatment.

10.
Front Med (Lausanne) ; 8: 796901, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35111780

RESUMEN

BACKGROUND: Tenofovir alafenamide fumarate has been used in late pregnancy; however, no data exist regarding its safety and effectiveness in early and middle pregnancy for mothers with hepatitis B virus infection. AIMS: To design a prospective study to investigate the efficacy and safety of TAF in pregnant women with chronic HBV infection during early-middle pregnancy. METHODS: Pregnant women with active chronic hepatitis B who received tenofovir alafenamide fumarate during early and middle pregnancy were enrolled and followed up until 6 months postpartum. Infants received immunoprophylaxis. The primary endpoint was the safety of mothers and infants. The secondary endpoints were maternal hepatitis B virus DNA reduction at delivery and mother-to-child transmission rate. RESULTS: Among 98 mothers enrolled, 31 initiated tenofovir alafenamide fumarate in early pregnancy, and 57 in middle pregnancy. The mean (± standard deviation) age was 29.00 (±3.81) years. At delivery, 100% (98/98) of the mothers achieved hepatitis B virus DNA levels <200,000 IU/L. Ninety-eight infants were born, and none had congenital defects or malformations. All infants received hepatitis B virus immunoprophylaxis. The mother-to-child transmission rate was 0%. Growth parameters including body weight, height, and head circumference were comparable to the national standards for physical development. No severe adverse effects were reported in either mothers or infants. No severe liver function damage occurred in any of the mothers. CONCLUSIONS: Initiating tenofovir alafenamide fumarate in early and middle pregnancy appears safe for both mothers and infants, and it is effective for controlling maternal disease as well as interrupting mother-to-child transmission.

11.
Infect Dis Ther ; 10(1): 281-290, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33146854

RESUMEN

INTRODUCTION: Sepsis is a complication in acute-on-chronic liver failure (ACLF) patients associated with high rates of mortality and morbidity. Early diagnosis of sepsis in ACLF patients can improve prognosis. This study aimed to explore potential effective biomarkers for the early diagnosis of sepsis in ACLF patients. METHODS: Ninety-four ACLF patients with sepsis were enrolled from 10 hospitals across China from January 2015 to June 2016 as well as 49 ACLF patients without infection from Xiangya Hospital. The first-day admission data and SOFA score and CLIF-SOFA score were collected. The differences of indicators between groups were compared with Kruskal-Wallis test. The receiver-operating characteristic (ROC) curve was analyzed to evaluate the diagnostic efficiency of the selected factors. RESULTS: Soluble triggering receptor expressed on myeloid cell-1 (sTREM-1) and presepsin were significantly higher in ACLF-sepsis patients compared with ACLF patients with no infection (P < 0.001). sTREM-1 and presepsin presented higher diagnostic value in sepsis for ACLF patients compared with other biomarkers [white blood cells (WBC), procalcitonin (PCT) and C-reactive protein (CRP)]. Combining sTREM-1 or presepsin with the CLIF-SOFA score increased the diagnostic efficiency (AUC = 0.876 or AUC = 0.913, respectively). CONCLUSIONS: sTREM-1 and presepsin are potential biomarkers for the early diagnosis of sepsis in ACLF patients. The combination of presepsin and the CLIF-SOFA score is a promising method for diagnosing sepsis in ACLF patients. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT02457637.

12.
Adv Sci (Weinh) ; 7(19): 2001431, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33042754

RESUMEN

Black phosphorus (BP), an emerging 2D material semiconductor material, exhibits unique properties and promising application prospects for photo/electrocatalysis. However, the applications of BP in photo/electrocatalysis are hampered by the instability as well as low catalysis efficiency. Recently, tremendous efforts have been dedicated toward modulating its intrinsic structure, electronic property, and charge separation for enhanced photo/electrocatalytic performance through structure engineering. Simultaneously, the search for new substitute materials that are BP-analogous is ongoing. Herein, the latest theoretical and experimental progress made in the structural/surface engineering strategies and advanced applications of BP and BP-analog materials in relation to photo/electrocatalysis are extensively explored, and a presentation of the future opportunities and challenges of the materials is included at the end.

13.
BMC Pregnancy Childbirth ; 20(1): 601, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-33028240

RESUMEN

BACKGROUND: Acute fatty liver of pregnancy (AFLP) is a potentially lethal condition of pregnant women with a high mortality rate. Potential predictors related to postpartum recovery time and prognostic factors of AFLP are still unclear. This study aimed to evaluate potential predictors for prognosis and postpartum recovery time of AFLP. METHODS: We retrospectively analyzed the clinical data of 76 AFLP patients in our hospital from 2002 to 2017 and investigated potential predictors using univariate analysis and multivariate logistic regression analysis. RESULTS: Hepatic encephalopathy (HE) was found to be associated with prognosis in AFLP patients (P = 0.005, OR = 26.844). The postpartum recovery time analysis showed that AFLP patients with a age < 25 had the shortest recovery time, but no significant difference (P = 0.134, OR = 5.952). The postpartum recovery time of patients with liver failure (LF) was significantly prolonged compared to those without LF (P = 0.036, OR = 10.052). Cryoprecipitate, and plasma infusion showed no significant effect on prognosis or recovery time. Artificial liver support therapy (ALST) had no effect on prognosis, but it might affect postpartum recovery time with no statistical significance (P = 0.128, OR = 5.470). CONCLUSION: HE is a potential predictor for prognosis of AFLP. LF is a potential predictor for postpartum recovery time.


Asunto(s)
Transfusión de Componentes Sanguíneos/estadística & datos numéricos , Hígado Graso/mortalidad , Encefalopatía Hepática/epidemiología , Periodo Posparto , Complicaciones del Embarazo/mortalidad , Adulto , Transfusión de Componentes Sanguíneos/métodos , Factor VIII/administración & dosificación , Hígado Graso/complicaciones , Hígado Graso/terapia , Femenino , Fibrinógeno/administración & dosificación , Humanos , Hígado Artificial , Embarazo , Complicaciones del Embarazo/terapia , Pronóstico , Estudios Retrospectivos , Medición de Riesgo/estadística & datos numéricos , Factores de Riesgo , Factores de Tiempo , Adulto Joven
14.
J Chem Phys ; 153(4): 044708, 2020 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-32752689

RESUMEN

Design of hybrid systems for photocatalytic application tends to be restricted by lacking interfacial coupling and fast charge recombination in the body competing with interface dynamics. In this work, the reduced carbon dots (rCDs) with numerous surface hydroxyl groups were deliberately anchored onto flower-like ZnO spheres with a highly exposed surface area to form heterointerfaces with sufficient interfacial electronic coupling. The incorporated rCDs evidently promote the light harvesting and charge separation of the binary hybrid system, resulting in highly enhanced photocatalytic Cr(VI) degradation performance. Ultrafast time-resolved spectra reveal that the surface C-OH bonds of rCDs play a crucial role at the heterointerfaces to regulate the charge dynamics. The long-lived surface C-OH states not only act as electron donors but also become electron mediators to rapidly capture the photoelectrons from the intrinsic state in the time-domain of 1 ps and induce a much longer lifetime for achieving highly efficient photoelectron injection from rCDs to ZnO. These results manifest that rCDs can be a promising photosensitizer to apply in photocatalytic pollutant treatment and energy conversion fields.

15.
Small ; 14(48): e1803132, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30307702

RESUMEN

Although 2D black phosphorus (BP) shows excellent optical and electronic properties, there are few reports on the photoluminescence (PL) properties of BP nanostructures because of the low yield of mechanical exfoliation, instability in water, and relatively weak emission. Herein, liquid exfoliation is combined with surface passivation to produce fluorescent BP quantum dots (BPQDs) with a high yield. The BPQDs exhibit strong PL in both ethanol and water and the absolute fluorescent quantum yield in water reaches 70%. Moreover, the BPQD solution exhibits stable PL for 150 d under ambient conditions and better photostability than conventional organic dyes and heavy-metal semiconducting nanostructures with intense fluorescence. The experiments and theoretical calculation reveal that the intense and stable PL originates from the intrinsic band-to-band excitation states and two surface states related to the POH and POCH2 CH3 bonding structures introduced by passivation. The polar water molecules remove many nonradiative centers and simultaneously increase the P-related fluorescent groups on the surface of BPQDs. Therefore, PL from the BPQDs in water is enhanced largely. The excellent fluorescent properties of BPQDs in an aqueous solution bode well for bioimaging and the negligible biotoxicity and distinct cell images suggest large potential in the biomedical and display fields.

16.
Nat Commun ; 9(1): 3366, 2018 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-30135422

RESUMEN

Photocatalytic hydrogen evolution from water has triggered an intensive search for metal-free semiconducting photocatalysts. However, traditional semiconducting materials suffer from limited hydrogen evolution efficiency owing to low intrinsic electron transfer, rapid recombination of photogenerated carriers, and lack of artificial microstructure. Herein, we report a metal-free half-metallic carbon nitride for highly efficient photocatalytic hydrogen evolution. The introduced half-metallic features not only effectively facilitate carrier transfer but also provide more active sites for hydrogen evolution reaction. The nanosheets incorporated into a micro grid mode resonance structure via in situ pyrolysis of ionic liquid, which show further enhanced photoelectronic coupling and entire solar energy exploitation, boosts the hydrogen evolution rate reach up to 1009 µmol g-1 h-1. Our findings propose a strategy for micro-structural regulations of half-metallic carbon nitride material, and meanwhile the fundamentals provide inspirations for the steering of electron transfer and solar energy absorption in electrocatalysis, photoelectrocatalysis, and photovoltaic cells.

17.
Small ; 13(8)2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27957803

RESUMEN

Ferromagnetism in semiconducting metal oxide nanoparticles has been intensively investigated due to their potential applications in spintronics, information storage, and biomedicine. Ferromagnetism can be produced in nonmagnetic metal oxide nanoparticles by a variety of methods or factors, but the saturated magnetization is typically of the order of 10-4 emu g-1 and too small to be useful in practice. In this work, it is demonstrated theoretically and experimentally that stronger ferromagnetism can be achieved in undoped nonmagnetic metal oxide semiconductors by exposing some specific polar crystal facets with carvings of special bonds via the interaction with underlying vacancies. In2 O3 microcubes with completely enclosed {001} polar facets show two orders of magnitude enhancement at room temperature compared to nanoparticles with an irregular morphology. The surface magnetic domains on the {001} facets account for the significantly enhanced ferromagnetism. The technique and concept described here can be extended to other types of metal oxide nanostructures to spur their application to spintronics.

18.
Nucleic Acids Res ; 43(Database issue): D59-67, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25378337

RESUMEN

Increasing amounts of genes have been shown to utilize alternative polyadenylation (APA) 3'-processing sites depending on the cell and tissue type and/or physiological and pathological conditions at the time of processing, and the construction of genome-wide database regarding APA is urgently needed for better understanding poly(A) site selection and APA-directed gene expression regulation for a given biology. Here we present a web-accessible database, named APASdb (http://mosas.sysu.edu.cn/utr), which can visualize the precise map and usage quantification of different APA isoforms for all genes. The datasets are deeply profiled by the sequencing alternative polyadenylation sites (SAPAS) method capable of high-throughput sequencing 3'-ends of polyadenylated transcripts. Thus, APASdb details all the heterogeneous cleavage sites downstream of poly(A) signals, and maintains near complete coverage for APA sites, much better than the previous databases using conventional methods. Furthermore, APASdb provides the quantification of a given APA variant among transcripts with different APA sites by computing their corresponding normalized-reads, making our database more useful. In addition, APASdb supports URL-based retrieval, browsing and display of exon-intron structure, poly(A) signals, poly(A) sites location and usage reads, and 3'-untranslated regions (3'-UTRs). Currently, APASdb involves APA in various biological processes and diseases in human, mouse and zebrafish.


Asunto(s)
Bases de Datos de Ácidos Nucleicos , Poliadenilación , Animales , Expresión Génica , Humanos , Internet , Ratones , Poli A/análisis , División del ARN , Pez Cebra/genética
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