Ferroelectric polarization promotes a CdS/In2Se3 heterostructure for photocatalytic water splitting.

The rapid recombination of photogenerated electrons and holes greatly limits the efficiency of photocatalyst based on semiconductor. In order to address this issue, we predicted a novel ferroelectric polarized heterojunction photocatalyst, CdS/In2Se3, which enables the spontaneous overall water splitting reaction. The CdS/In2Se3 heterojunction exhibits a band-edge staggered alignment and it is easy to form a direct Z-scheme charge transfer pathway. Besides, the built-in electric field (Eint) in the CdS/In2Se3 heterojunction promoted the charge transfer of CdS/In2Se3, leading to an improved separating efficiency of photo-generated carriers. Moreover, the vertical intrinsic polarized electric field (Ep) not only alters the position of the band edge but also reduces the bandgap limitations commonly associated with photocatalytic materials. Furthermore, the CdS/In2Se3 heterojunctions demonstrate separate catalytic activity for the hydrogen evolution reaction (HER) on the surface of the CdS monolayer and oxygen evolution reaction (OER) on the surface of In2Se3, respectively. Notably, the CdS/In2Se3-down configuration enables spontaneous photocatalytic water splitting in pH = 7, while the CdS/In2Se3-up configuration efficiently facilitates the HER process. This study highlights the significant advantages of CdS/In2Se3 heterojunctions as photocatalytic materials, offering unique insights into the development and research of this promising heterojunction architecture.

The polarized electric field of CdTe/B4C3 heterostructure efficiently promotes its photocatalytic overall water splitting.

Inspired by natural photosynthesis, two-dimensional van der Waals (vdW) heterostructures are considered as promising photocatalysts for solar-driven water splitting and they attract ever-growing interest. A type-II vdW hetero-photocatalyst (CdTe/B4C3) integrating the polarized CdTe into metal-free B4C3 was constructed, which could achieve solar-driven spontaneous overall water splitting at pH = 0-7 and exhibit a high solar-to-hydrogen (STH) efficiency of 19.64%. Our calculation results show that the interlayer interaction between the CdTe and B4C3 monolayers in the heterostructure creates an interfacial electric field enhanced by the intrinsic dipole of polarized CdTe, which accelerates the effective separation of photogenerated carriers and makes the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) take place separately on the B4C3 and CdTe layers. Furthermore, the CdTe/B4C3 heterostructure has decent band edge positions to promote the redox reaction to decompose water due to the significant electrostatic potential difference in the CdTe/B4C3 heterostructure and it could trigger spontaneous redox reaction under light at pH = 0-7. This work is helpful for us to design type-II heterojunction photocatalysts with high efficiency of photogenerated carrier separation for overall water splitting.

Predictors of relapse after cessation of nucleos(t)ide analog treatment in HBeAg-negative chronic hepatitis B patients: A meta-analysis.

OBJECTIVES: The aim of this study was to identify the predictors of relapse after the withdrawal of nucleos(t)ide analog (NA) therapy in patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB). METHODS: The PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science databases were searched through January 2019. A random-effects model meta-analysis was performed, with hazard ratios (HR) and 95% confidence intervals (CI) used as summary statistics. RESULTS: Seventeen studies were included in the meta-analysis. Age (HR=1.022 per year), baseline hepatitis B surface antigen (HBsAg) (HR=1.509 per log IU/l), end of treatment (EOT) HBsAg level (HR=1.896 per log IU/l), EOT HBsAg level ≥1000 IU/ml (HR=1.749), and HBsAg decline from baseline to EOT (HR=0.748 per log IU/l) were associated with virological relapse. The predictors of clinical relapse were baseline HBsAg level (HR=1.312 per log IU/l), EOT HBsAg level (HR=1.458 per log IU/l), EOT HBsAg level ≥100IU/ml (HR=3.199) or ≥1000 IU/ml (HR=1.810), and duration of consolidation therapy (HR=0.991 per month). CONCLUSIONS: This meta-analysis indicates that age, the duration of consolidation therapy, and levels of baseline and EOT HBsAg were factors predictive of relapse in HBeAg-negative CHB patients who discontinued NA treatment.

Removal of NO with the hexamminecobalt solution catalyzed by the carbon treated with oxalic acid.

NO can be removed at the same time with SO2 by aqueous Co(NH3)62+ solution. The reduction of Co(NH3)63+ to Co(NH3)62+ is catalyzed by activated carbon to regain the NO absorption ability of the scrubbing solution. Oxalic acid solution is explored to change the carbon surface to ameliorate its catalytic capability. The experimental results suggest that the best catalyst is prepared by impregnating the carbon sample in 0.7 mol l-1 oxalic acid solution for 24 h followed by being activated at 600 °C for 5 h under nitrogen atmosphere. After being treated with oxalic acid solution, the surface area and the acidity on the carbon surface increase. The experiments show that the carbon modified with oxalic acid can get a much higher NO removal efficiency than the original carbon.

Telbivudine therapy may shape CD4(+) T-cell response to prevent liver fibrosis in patients with chronic hepatitis B.

BACKGROUND & AIMS: Nucleos(t)ide analogues (NAs) can indirectly restore host immunity against hepatitis B virus (HBV) by inhibiting virus replication. We aimed to investigate whether telbivudine could prevent HBV-related fibrosis progression by their influence on CD4(+) T-cell response. METHODS: Thirty-six HBeAg-positive patients with chronic hepatitis B (CHB) were enrolled for 52-week telbivudine monotherapy and were followed at treatment week (TW)-0, 4, 12, 24 and 52. By TW-52, the patients were classified into a complete-response group (CR, n = 10) with both negative HBV-DNA and HBeAg, or a part-response group (PR, n = 11) only with negative DNA, or a non-response group (NR, n = 15) still with positive DNA. The peripheral blood mononuclear cells (PBMCs) were prepared for further flow cytometric and real-time PCR analyses, and also for the in vitro experiments with primary hepatic stellate cells (HSCs). RESULTS: Peripherally, all chronic HBV-infected subjects showed the involvement of CD4(+) T-cell responses, among whom the inactive carriers (IC) had Th1 (CD4(+) IFNγ(+) ) dominated, CHB had Th17 (CD4(+) IL-17(+) ) dominated, while the immune tolerant (IT) subjects had Treg (CD4(+) CD25(high) Foxp3(+) ) dominated. Besides, we found the therapeutic responses to telbivudine were especially associated with up-regulation of Th1 and Th17, and down-regulation of Treg. Furthermore, compared to CD4(+) cells from CR, those from NR could in vitro significantly exacerbate cell activation, proliferation and cytokine production of HSCs, which were partly mediated by IL-4 and TGF-ß1. CONCLUSIONS: Telbivudine might slow down HBV-related liver fibrosis progression by restoring CD4(+) T-cell responses against HBV.

Inhibiting CB1 receptors improves lipogenesis in an in vitro non-alcoholic fatty liver disease model.

BACKGROUND: The endocannabinoids system (ECs) mediated mainly by CB1 and CB2 receptors plays an important role in non-alcoholic fatty liver disease by regulating lipid metabolism. This study is to further investigate the expression of CB1 and CB2 in the fat accumulation liver cells and to identify possible underlying mechanism by detecting the key lipogenesis factors. METHODS: Sodium oleate and sodium palmitate were added into the HepG2 cell line for forming fat accumulation liver cell. MTT assay was used to test the cell's cytotoxicity. The accumulation rate of fat in HepG2 cell was analyzed by the fluorescent staining. The mRNA and protein expression levels of CB1, CB2, SREBP-1c, ChREBP, L-PK, ACC1, FAS, LXRs and RXR were detected by RT-PCR and Western blot before and after the use of the antagonist. RESULTS: The receptors of CB1 were expressed in HepG2 cells with low levels while in HepG2 fatty liver cells with higher levels (p < 0.05). However, after the application of antagonist, the expressions were significantly decreased (p < 0.05). The expressions of SREBP-1c, ChREBP and LXRs were detectable in HepG2 cells and the expressions were increased in HepG2 fatty liver cells (p < 0.05). After using the antagonists, the expressions of SREBP-1c, ChREBP, LXRs, ACC1 and FAS were significantly decreased (p < 0.05). But L-PK and RXR changed little in two groups (p > 0.05). CONCLUSION: Results of the present study demonstrated that CB1 receptors had important pathophysiological effects on the formation of fatty liver. CB1 receptors could be regulated by SREBP-1c, ChREBP and LXRs. Therefore, targeting CB1 receptors for the treatment of NAFLD might have a potential application value.

[Clinical and medication characteristics of senior hospitalized patients with chronic constipation].

OBJECTIVE: To analyze the clinical features, risk factors and drug uses of senior hospitalized patients with chronic constipation. METHODS: A total of 162 hospitalized patients aged 85 years and over at our hospital during the period of January-March 2012 conducted a questionnaire survey. There were 137 males and 25 females. And 112 cases of chronic constipation were diagnosed in accordance with the Rome III criteria. The survey included general condition, risk factors of constipation, spectrum of symptoms, associated symptoms, previous medication and medication for constipation after admission. The results were statistically analyzed by Logistic regression. RESULTS: Their average age was (90 ± 4) years old. And the total prevalence of chronic constipation was 69.1% (112/162). Logistic regression analysis showed that less activity (OR = 10.873) and diet (OR = 4.752) were the important risk factors. Defecation effort was the most common symptom (n = 85, 75.9%). A total of 88 cases (78.6%) took lactulose alone or lactulose plus other laxatives. The reasons of using lactulose were as follows: dietary restrictions (n = 31, 35.2%), aspiration prevention (n = 21, 23.9%) and poor efficacy of other laxatives (n = 36, 40.9%). CONCLUSIONS: Prevalence of constipation is high among senior hospitalized patients. Less activity and diet are the main risk factors. And lactulose should be a first-line therapy.

Role of RhoA in platelet-derived growth factor-BB-induced migration of rat hepatic stellate cells.

BACKGROUND: Although the migration of hepatic stellate cells (HSCs) is essential for hepatic fibrotic response, the detailed mechanisms involved are poorly understood. The aim of this study was to examine the role of Rho GTPases (especially RhoA) in platelet-derived growth factor (PDGF)-BB-induced migration of HSCs. METHODS: The migration of primary rat HSCs was evaluated using transwell Boyden chamber, while cytoskeletal changes were visualized by immunofluorescence staining of intracellular actins and vinculin. Quantitative real-time PCR and Western blotting analysis were used to detect the expression of Rho GTPases (RhoA, Rac1 and Cdc42) within HSCs and their activation was determined by glutathione S-transferase pull-down assay. Finally, the effects of RhoA on PDGF-BB-induced cell migration and cytoskeletal remodeling were analyzed using HSC-T6 cells stably transfected with constitutively active (CA, Q63L) or dominant negative (DN, T19N) RhoA mutants. Data were analyzed using SPSS 16.0 software. Student's t test was used to analyze differences between two groups and one-way analysis of variance (ANOVA) was used among multiple groups. RESULTS: Rapid cytoskeletal remodeling led to a significant increase in the motility of primary rat HSCs after haptotactic (direct) and chemotactic (indirect) stimulation by PDGF-BB. PDGF-BB caused a dramatic elevation in the levels of both total and active RhoA protein. However, the levels of mRNA for Rho GTPases, including RhoA, Rac1 and Cdc42, were unaffected. Furthermore, PDGF-BB induced increased formation of stress fibers and focal adhesions in HSC-T6 cells transfected with CA-RhoA, but not in HSC-T6 transfected with DN-RhoA. Surprisingly, both CA- and DN-RhoA-transfected HSC-T6 cells showed decreased migratory potential in the absence or presence of PDGF-BB compared with controls. CONCLUSIONS: PDGF-BB induced cytoskeletal remodeling in rat HSCs and promoted their migration via regulation of intracellular RhoA. RhoA may be one of the determinants in PDGF-BB-induced HSC migration.