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1.
Int J Mol Sci ; 20(17)2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31470507

RESUMO

Imbalance of lipid metabolism is a main cause of metabolic syndrome leading to life-threatening metabolic diseases. Angiopoietin-like protein 8 (Angptl8) was recently identified as a liver and adipose tissue-released hormone that is one of the molecules involved in triglyceride metabolism. However, the regulatory mechanism of Angptl8 is largely unknown. A high fat diet (HFD)-fed mouse model, which showed high cholesterol, high triglyceride, and high insulin in the blood, revealed the upregulation of hepatic and plasma Angptl8 and the downregulation of hepatic glycine N-methyltransferase (GNMT). The inverse correlation of hepatic Angptl8 and GNMT expression in the livers of HFD-fed mice was also confirmed in a publicly available microarray dataset. The mechanistic study using primary hepatocytes showed that the Angptl8 expression could be induced by insulin treatment in a dose- and time-dependent manner. Inhibition of PI3K/Akt pathway by the specific inhibitors or the dominant-negative Akt blocked the insulin-induced Angptl8 expression. Moreover, knockout of GNMT promoted the Akt activation as well as the Angptl8 expression. These results suggested that GNMT might be involved in insulin-induced Angptl8 expression in HFD-mediated metabolic syndrome.

2.
PLoS One ; 14(9): e0221946, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31483834

RESUMO

OBJECTIVES: Despite the ease of health care access and the waiver of copayments for cancer patients, treatment is delayed in a small proportion of Taiwanese patients diagnosed with cervical cancer. In this study, we explored the relationship between the time interval from diagnosis to treatment and survival in cervical cancer patients. MATERIAL AND METHODS: The study was a retrospective population-based observational study conducted between 2004 and 2010. In Taiwan, 12,020 patients were newly diagnosed with cervical cancer from 2004 to 2010, and 9,693 patients (80.6%) were enrolled in our final analysis. RESULTS: Most of the patients received treatment within 90 days of diagnosis (n = 9,341, 96.37%). After adjustment for other variables, patients who received treatment between 90 and 180 days and >180 days after diagnosis had a 1.33 (95% CI: 1.02-1.72, P < 0.05) and 1.36 (95% CI: 1.12-1.65, P < 0.05) times higher risk of death, respectively, than those who received treatment within 90 days. Kaplan-Meier analysis showed that the patients treated after 90 days from diagnosis had a lower overall survival rate than those treated within 90 days. In analysis stratifying the patients according to their initial tumor stage, namely stages I and II and stage III and IV, the time interval from diagnosis to treatment remained a significant prognosticator in those who received treatment >180 days after diagnosis. CONCLUSION: A longer interval between diagnosis and treatment is associated with poorer prognosis among cervical cancer patients.

3.
Arch Gynecol Obstet ; 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31485778

RESUMO

OBJECTIVE: To investigate the prevalence and explore potential risk factors of depression and anxiety in patients with recurrent pregnancy loss (RPL). METHODS: 1138 non-pregnant women aged 20-40 years old who attempted to conceive were invited to complete a questionnaire, including basic information, Self-Rating Depression Scale (SDS) and Self-Rating Anxiety Scale (SAS). RESULTS: 782 RPL women, 218 women with one pregnancy loss and 138 women with no history of pregnancy loss were included in this study. We found that both RPL patients and women with one pregnancy loss had significantly higher SDS and SAS scores than the control group (P = 0.006, 0.003). Furthermore, in RPL patients, those with lower education level (lower than university), lower household income (< 10,000 yuan) and history of induced abortion had significantly higher levels of depression and anxiety. Women with multiple pregnancy losses ( ≥ 3) and no live birth had significantly higher SDS scores. Women who had been married for 3 years or more had a significantly higher SAS score. Logistic regression revealed that lower education level (lower than university) was an independent risk factor for depression (adjusted OR = 1.75, 95% CI 1.10-2.77, P = 0.018) and anxiety (adjusted OR = 1.80, 95% CI 1.04-3.13, P = 0.037), and women with three or more pregnancy losses had increased odds of depression than those with two pregnancy losses (adjusted OR = 1.82, 95% CI 1.15-2.88, P = 0.012). CONCLUSION: RPL patients are more likely to develop depression and anxiety than women with no history of pregnancy loss. Lower education level and multiple pregnancy losses (≥ 3) appear to be two independent risk factors of depression and anxiety in women with RPL. Women with one pregnancy loss also show a significant higher level for depression and anxiety. Appropriate psychological intervention can be considered for such patients.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31487149

RESUMO

Photodynamic therapy (PDT) as a noninvasive and selective treatment technology has presented great potential in cancer prevention and precision medicine, but its therapeutic efficacy is still greatly inhibited by the limitations of photosensitizers (PSs) in the microenvironment such as the aggregation caused quenching (ACQ) of PSs. Herein, we proposed an "acid-triggered nanoexpansion" method to further reduce the aggregation of photosensitizers by constructing acetal-based polymeric micelles. A pH-responsive amphiphilic block copolymer, POEGMA-b-[PTTMA-co-PTPPC6MA] was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and self-assembled into spherical micelles. In the normal physiological environment, the micelles were stable and had good biocompatibility. Upon entry into the acidic microenvironment of the tumor, the acid-responsive hydrophobic 2, 4, 6-trimethoxybenzaldehyde in the micelles hydrolyzed and generated a hydrophilic diol moiety. Although the hydrophility of the micellar core was increased, the assembled structure of block copolymers was not dissociated but expanded. The responsive expansion of the micelles could allow the photosensitizers to well-disperse in the core, whereas more tumor-dissolved oxygen entered the micelles. This phenomenon could provide a better nanoenvironment for photosensitizers to reduce the ACQ of the photosensitizers, leading to more singlet oxygen (1O2) produced under the laser irradiation (650 nm). Both in vitro and in vivo studies have demonstrated that the remarkable photodynamic therapeutic efficacy of acid-responsive micelles could be realized. Thus, the acid-triggered nanoexpansion method might provide more possibilities to develop efficient platforms for treating cancers.

5.
Postgrad Med J ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488620

RESUMO

BACKGROUND: The prognostic value of serum uric acid (SUA) for incident acute coronary syndrome (ACS) in hypertensive subjects is uncertain. Therefore, the present study examined the association between SUA and incident ACS in a large cohort of Chinese hypertensive adults. METHODS: This was a retrospective cohort study, which enrolled 5473 Chinese community-dwelling hypertensive patients from 1 January 2012 to 31 December 2012. Study outcomes were ACS events, and patients were followed until 31 December 2016. Cox regression analyses were conducted to determine adjusted HRs and 95% CIs for baseline SUA tertiles (low, middle and high group) and for men and women separately. RESULTS: A total of 5473 participants were included in the analysis (median follow-up was 4.5 years). Participants were divided into tertiles based on SUA levels. During follow-up, 9 (0.49%), 14 (0.77%) and 25 (1.37%) patients developed ACS in the lowest, middle and highest tertiles, respectively. When compared with the lowest tertile of SUA, the highest tertile of SUA was associated with ACS risk in all subjects and in men and women separately (HR: 2.62, 95% CI 1.14 to 7.01, p=0.0233; 2.15, 95% CI 1.08 to 6.04, p=0.021, and 3.49, 95% CI 1.25 to 7.74, p=0.017, respectively). CONCLUSIONS: Higher SUA levels were independently associated with an elevated risk of ACS incidence. The relationship between SUA levels and ACS in hypertensive patients was J-shaped.

6.
Complement Ther Clin Pract ; 36: 100-112, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31383426

RESUMO

BACKGROUND: Acupuncture has been used to treat type 2 diabetes (T2DM) for 2000 years and there are emerging clinical evidence and animal studies for its efficacy. However, we are unable to conclude the effectiveness and safety on this issue yet. OBJECTIVES: To assess the effects and safety of acupuncture for T2DM. METHODS: We systematically searched 5 databases and 2 clinical registry platforms from inception to 2018-6-4. RCTs for acupuncture or its variants compared with sham acupuncture or no acupuncture controls for T2DM were included. The primary outcomes were glycemic control and adverse events. RESULTS: A total of 21 studies, which comprised a total of 1943 participants, were included in the final meta-analysis. Compared with sham acupuncture or no acupuncture plus baseline treatments, acupuncture plus baseline treatments yield reduction in FBG(MD 1.21 mmol/l, 95%CI 1.56 to 0.87), 2 h BG(MD 2.13 mmol/l, 95%CI 2.79 to 1.46), HA1c (MD 1.12%, 95%CI 1.62 to 0.62). Our results also show acupuncture can improve blood lipids and blood pressure control, and reduce weight. CONCLUSIONS: As one type of multifactorial intervention, acupuncture could be recommended as a supplementary treatment in the management of T2DM, especially in those with obesity or metabolic disorders. However, due to the small sample size, poor methodological quality of trials reviewed, the amount of evidence is not fully convincing. There is a need for well-planned, long-term studies. REGISTRATION: International Prospective Register of Systematic Reviews (Number CRD42018094573).

7.
Int Urol Nephrol ; 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385180

RESUMO

PURPOSE: In large observational studies of adult kidney transplant recipients (KTRs) where older adults (65 years old and older) were not well represented, the mammalian target of rapamycin inhibitors (mTOR inhibitors) has poorer outcomes than the standard tacrolimus-mycophenolate-steroids (TAC-MPA-S) regimen. We conducted this study to compare the outcomes of regimens containing the common mTOR inhibitor, sirolimus (SRL) against TAC-MPA-S in older adult KTRs. METHODS: Using the 2000-2016 Scientific Registry of Transplant Recipients, Cox multivariable regression models were conducted to analyze the patient and graft outcomes associated with regimens containing SRL, steroids (S) and cyclosporine (CSA), tacrolimus (TAC), or mycophenolate (MPA) vs. the standard (TAC-MPA-S) regimen in older adult KTRs. RESULTS: Included in the analysis were 15,008 (95.19%) older adult KTRs on standard (TAC-MPA-S) regimen, 242 (1.53%) on SRL-MPA-S, 300 (1.90%) on SRL-TAC-S, and 217 (1.38%) on SRL-CSA-S. Compared with the standard regimen, the adjusted risks of all-cause death and overall graft loss over a maximum 5-year follow-up were highest with SRL-MPA-S, intermediate with SRL-TAC-S and not significantly different with SRL-CSA-S. The adjusted risks of all-cause death and overall graft loss were modified by a pre-transplant history of malignancy in older adult KTRs on SRL-TAC-S, not in those on SRL-MPA-S or SRL-CSA-S. CONCLUSIONS: In older adult kidney transplant recipients, SRL-TAC-S or SRL-MPA-S, but not SRL-CSA-S is associated with higher risks of death and allograft loss than standard TAC-MPA-S regimen and a pre-transplant malignancy history worsens these risks in patients on SRL-TAC-S. Confirmation of our findings by a prospective randomized trial is needed before translation into clinical practice can be recommended.

8.
Neurosurg Rev ; 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375952

RESUMO

Previous finite element studies of thoracolumbar fractures were mostly based on simulation analysis of one single object, which was difficult to objectively evaluate the differences between conventional pedicle screws and Schanz pedicle screws. The aim of this study was to evaluate the stress of screw and injured vertebrae displacement using the finite element model of conventional pedicle screw and Schanz pedicle screw instrumentation for the treatment of lumbar 1 fractures. Data of eight healthy volunteers were used to simulate the finite element model. The instrumentation models were divided into four groups: moderate fracture conventional (MC), moderate fracture Schanz (MS), unstable/severe fracture conventional (UC), and unstable/severe fracture Schanz (US) pedicle screw groups. The maximum screw stress and lumbar 1 displacement/micro-motion in each group increased with the increase of torque and/or load. Under the same fracture, maximum von Mises stress of conventional pedicle screw (MC/UC) was larger than Schanz pedicle screw (MS/US) (P < 0.05) and lumbar 1 displacement/micro-motion of Schanz pedicle screw (MS/US) was larger than conventional pedicle screw (MC/UC) (P < 0.05). Under the same screws, the maximum von Mises stress and displacement/micro-motion of unstable fracture (UC/US) were larger than moderate fracture (MC/MS) (P < 0.05). Posterior short-segment instrumentation with Schanz pedicle screws were recommended for unstable fractures. The compression displacement/micro-motion of bony defect during flexion may lead to the postoperative re-collapse of injured vertebrae.

9.
Pediatr Cardiol ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367953

RESUMO

Integrin receptors enable cells to sense and respond to their chemical and physical environment. As a class of membrane receptors, they provide a dynamic, tightly regulated link between the extracellular matrix or cellular counter-receptors and intracellular cytoskeletal and signaling networks. They enable transmission of mechanical force across the plasma membrane, and particularly for cardiomyocytes, may sense the mechanical load placed on cells. Talins and Kindlins are two families of FERM-domain proteins which bind the cytoplasmic tail of integrins, recruit cytoskeletal and signaling proteins involved in mechano-transduction, and those which synergize to activate integrins, allowing the integrins to physically change and bind to extracellular ligands. In this review, we will discuss the roles of talin and kindlin, particularly as integrin activators, with a focus on cardiac myocytes.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31368773

RESUMO

Objective: A systematic review and meta-analysis of randomized controlled trials (RCTs) were conducted to assess the benefits and harms of vitamin D supplementation for attention-deficit/hyperactivity disorder (ADHD) patients. Methods: We followed the standard methodological procedures of the Cochrane Handbook for Systematic Reviews of Intervention. PubMed, Embase, the Cochrane Central Register of Controlled Trials, Science and Conference Proceedings Citation Index-Social Science and Humanities (Web of Science), ClincalTrials.gov, and World Health Organization's International Clinical Trials Registry Platform were searched for RCTs in January 2019. Independently, two authors (J.G., T.X.) extracted data, assessed the risk of bias, combined the data, and graded evidence quality using the Grading of Recommendations Assessment, Development, and Evaluation approach. Our primary outcomes were assessed through rating scales of ADHD severity. Secondary outcomes measured were the possible adverse effects of vitamin D supplementation and vitamin D status after supplementation for ADHD. Results: We included four RCTs with 256 children addressing vitamin D supplementation as adjunctive therapy to methylphenidate on ADHD symptoms. Vitamin D supplementation demonstrated a small but statistically significant improvement in ADHD total scores, inattention scores, hyperactivity scores, and behavior scores. The improvement was likely limited due to the low to very low quality of evidence in the literature. There was no statistically significant improvement in oppositional scores. Reported adverse events in the vitamin D group were mild and not significantly different from the control group. Vitamin D supplementation increased serum vitamin D levels and the ratio of patients with sufficient vitamin D levels. Conclusions: Vitamin D supplementation as adjunctive therapy to methylphenidate appeared to reduce ADHD symptoms without serious adverse events, associated with improved vitamin D status. However, considering the generally low strength of evidence, well-designed RCTs are needed to determine the efficacy and safety of vitamin D supplementation for both children and adults with ADHD, especially in the setting of a combination of vitamin D and other ADHD treatments.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31443003

RESUMO

OD bundling is a promising method to identify key origin-destination (OD) patterns, but the bundling can mislead the interpretation of actual trajectories traveled. We present OD Morphing, an interactive OD bundling technique that improves geographical faithfulness to actual trajectories while preserving visual simplicity for OD patterns. OD Morphing iteratively identifies critical waypoints from the actual trajectory network with a min-cut algorithm and transitions OD bundles to pass through the identified waypoints with a smooth morphing method. Furthermore, we extend OD Morphing to support bundling at interaction speeds to enable users to interactively transition between degrees of faithfulness to aid sensemaking. We introduce metrics for faithfulness and simplicity to evaluate their trade-off achieved by OD morphed bundling. We demonstrate OD Morphing on real-world city-scale taxi trajectory and USA domestic planned flight datasets.

12.
J Virol ; 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462563

RESUMO

The global health burden for hepatitis C virus (HCV) remains high, despite available effective treatments. To eliminate HCV, a prophylactic vaccine is needed. One major challenge in the development of a vaccine is the genetic diversity of the virus, with 7 major genotypes and many subtypes. A global vaccine must be effective against all HCV genotypes. Our previous data showed that the 1a E1/E2 glycoprotein vaccine component elicits broad cross-neutralizing antibodies in humans and animals. However, some variation is seen in the effectiveness of these antibodies to neutralize different HCV genotypes and isolates. Of interest was the differences in neutralizing activity against two closely related isolates of HCV genotype 2a, the J6 and JFH-1 strains. Using site-directed mutagenesis to generate chimeric viruses between J6 and JFH-1 strains, we found that variant amino acids within the core E2 glycoprotein domain of these two HCV genotype 2a viruses do not influence isolate-specific neutralization. Further analysis revealed that the N-terminal hypervariable region 1 (HVR1) of the E2 protein determines the sensitivity of isolate-specific neutralization and the HVR1 of the resistant J6 strain binds scavenger receptor class-B type-1 (SR-B1), while the sensitive JFH-1 stain does not. Our data provides new information on mechanisms of isolate-specific neutralization to facilitate the optimization of a much-needed HCV vaccine.Importance A vaccine is still urgently needed to overcome the HCV epidemic. It is estimated that 1.75 million new HCV infections occur each year, many of which will go undiagnosed and untreated. Untreated HCV can lead to continued spread of the disease, progressive liver fibrosis, cirrhosis and eventually end-stage liver disease and/or hepatocellular carcinoma (HCC). Previously, our 1a E1/E2 glycoprotein vaccine was shown to elicit broadly cross-neutralizing antibodies, however, there remains variation in the effectiveness of these antibodies against different HCV genotypes. In this study, we investigated determinants of differential neutralization sensitivity between two highly related genotype 2a isolates, J6 and JFH-1. Our data indicates that HVR1 region determines neutralization sensitivity to vaccine antisera through modulation of sensitivity to antibodies and interactions with SR-B1. Our results provide additional insight into optimizing a broadly neutralizing HCV vaccine.

13.
Lipids Health Dis ; 18(1): 163, 2019 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31421673

RESUMO

BACKGROUND: The magnitude and direction of association of low-density lipid cholesterol (LDL-C) with diabetes mellitus (DM) might differ by hypertensive status, but there is limited epidemiological evidence in China. METHODS: We examined the association between LDL-C levels and DM in 9892 participants with hypertension using logistic regression. Participants were stratified into three groups according to LDL-C levels (desirable, borderline high or high), then further divided into quartiles. Restricted cubic spline regression models, subgroup analysis and interaction tests were also conducted to evaluate the shape of association. RESULTS: After adjusting for covariates, lower LDL-C had a significant and inverse association with the likelihood of DM in all participants (OR: 0.944, 95% CI = 0.893, 0.998). In participants with desirable LDL-C concentrations (< 3.4 mmol/L), LDL-C protected against DM (OR = 1.240, 95% CI = 1.076, 1.429 per 1 mmol/L decrease). In participants with higher LDL-C concentrations (> 4.1 mmol/L), LDL-C increased the DM likelihood (OR = 1.536, 95% CI = 1.126, 2.096 per 1 mmol/L increase). Restricted cubic spline regression also found a U-shaped association between LDL-C levels and DM prevalence. CONCLUSIONS: There was a U-shaped association between LDL-C levels and DM in Chinese patients with hypertension.

14.
Kaohsiung J Med Sci ; 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31433118

RESUMO

The gold standard of antituberculosis susceptibility testing is based on culture method which takes weeks. Rapid detection of resistance to isoniazid (INH) and rifampin (RIF) to avoid inappropriate regimens and to prevent transmission of resistant strains are important. A membrane array (BluePoint MTBDR) was developed to identify Mycobacterium tuberculosis complex (MTBC) and the genetic mutations responsible for resistance to RIF and INH. We aimed to evaluate the performance of this array for diagnosing drug-resistant MTBC. A total of 261 acid-fast bacilli positive sputum specimens, 1025 positive mycobacteria growth indicator tube (MGIT) cultures and 544 clinical isolates were analyzed. Antituberculosis susceptibility testing was the gold standard and was performed on MTBC isolated from positive MGIT cultures and on 544 clinical isolates. The sensitivity and specificity of the array to detect MTBC were 62.2% and 88.1% for sputum specimens, 100% and 97.9% for MGIT cultures. For detection of drug-resistant MTBC in positive MGIT tubes, the sensitivities of the array were 100% for RIF and 97.1% for INH, while the specificities were 99.7% and 100%, respectively. Interestingly, we noticed four genotypically RIF-resistant but phenotypically RIF-susceptible isolates and eight genotypically INH resistant but phenotypically INH-susceptible isolates. Comparing with conventional culture methods for species identification and drug susceptibility testing, the BluePoint MTBDR assay demonstrated to be a rapid test with high sensitivity and specificity to identify MTBC and to detect isoniazid and rifampin resistance when it is applied to broth culture specimens and clinical isolates.

15.
Biomed Pharmacother ; 118: 109276, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31377466

RESUMO

BACKGROUND: Paeonia lactiflora (PL) was widely used for pain relief, but its effects on migraine headaches remain unclear. PURPOSE: The aim of the present study was to investigate the effects of PL on migraine headaches. METHODS: First, we found that PL was frequently used in Taiwan for headache treatment based on data from Taiwan's National Health Insurance Research Database. Migraine was induced through the intraperitoneal injection (i.p.) of nitroglycerin (NTG, 10 mg/kg) in rats. Pretreatment with PL was administered orally 30 min prior to the NTG i.p. Migraine headache behavior was observed by video-recordings. Finally, the rats were sacrificed and brain was removed for immunohistochemistry staining analysis. RESULTS: The frequency and total time spent rearing up and sniffing in exploratory behavior, and walking in locomotor behavior, were reduced in the NTG group compared with the control group (all p <  0.001). This reduction could be ameliorated by pretreatment with PL 1.0 g/kg (all p <  0.05). Total time spent in the light chamber was lower in the NTG group compared with the control group (p <  0.05); this could be ameliorated by pretreatment with 1.0 g/kg PL (p <  0.05). The rats in the NTG group spent longer time on the smooth surface than those in the control group (p <  0.001); this could be shortened by pretreatment with 0.5 and 1.0 g/kg PL (both p <  0.01). The traveling distance of rats in the NTG group was shorter than in the control group (p <  0.001); rats given 1.0 g/kg PL had a longer traveling distance than those in the NTG group (p <  0.01). Both c-fos and CGRP immunoreactive cells increased in the TNC in the NTG group compared with that of the control group (both p <  0.001); this increased could be reduced by pretreatment with PL 0.5 and 1.0 g/kg (both p <  0.05). CONCLUSION: Pretreatment with PL ameliorated migraine headache behaviors in the NTG-induced migraine rat model, suggesting pretreatment with PL is beneficial for migraine headache treatment. This effect of PL is related to the decrease of c-fos and CGRP in the TNC. However, still there are too many methodological limitations which need to be overcome in further experiments to support the data.

16.
Bioresour Technol ; 291: 121898, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31395402

RESUMO

With the intensive development of lignocellulosic biorefineries to produce fuels and chemicals from biomass-derived carbohydrates, lignin was generated at a large quantity every year. Therefore, lignin has received increasing attention as an abundant aromatics resource in terms of research and development efforts for value-added chemicals production. In this review, studies about lignin degradation especially the crucial enzymes involved and the reaction mechanism were substantially discussed, which provided the molecular basis of lignin biodegradation. Then, the latest improvements in lignin valorization by biological methods were summarized and case studies about value-added compounds from lignin were introduced. Afterwards, challenges, opportunities and prospects regarding biorefinery of lignin were presented.

17.
ACS Appl Mater Interfaces ; 11(34): 30786-30792, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31362488

RESUMO

Surface defects in semiconductors have a significant role to tune the photocatalytic reactions. However, the dominant studied defect type is oxygen vacancy, and metal cation vacancies are seldom explored. Herein, bismuth vacancies are engineered into BiOBr through ultrathin structure control and employed to tune photocatalytic CO2 reduction. VBi-BiOBr ultrathin nanosheets deliver a high selective CO generation rate of 20.1 µmol g-1 h-1 in pure water, without any cocatalyst, photosensitizer, and sacrificing reagent, roughly 3.8 times higher than that of BiOBr nanosheets. The increased CO2 reduction activity is ascribed to the tuned electronic structure, optimized CO2 adsorption, activation, and CO desorption process over VBi-BiOBr ultrathin nanosheets. This work offers new opportunities for designing surface metal vacancies to optimize the CO2 photoreduction performances.

18.
Neurosci Lett ; 711: 134439, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31425825

RESUMO

In this research, we intended to evaluate the expression pattern, distribution and sources of Galectin-3 (Gal-3) in perinatal hypoxic-ischemic brain injury rat model. Postnatal day 3 Sprague-Dawley rat pups were subjected to right carotid artery ligation followed by 2.5 h of hypoxia (6% oxygen). Expression and distribution of Gal-3 were evaluated by western blotting and immunofluorescence. Sources of Gal-3 were evaluated by double staining with neuronic, oligodendrocytic, astrocytic, microglial and endotheliocytic markers. Our results indicated Gal-3 significantly upregulated from 12 h and maintained an increasing tendency within 72 h post injury. Although the relative expression of Gal-3 decreased after 72 h, we detected significant differences until 14d. We found Gal-3 started to distribute in cortex and thalamus area and maintained an increasing tendency. Gal-3 could be detected in cortex, thalamus, corpus callosum and hippocampus area at 72 h post injury. After that, expression of Gal-3 in cortex and thalamus area downregulated, the expression in corpus callosum and hippocampus area vanished. We found astrocyte, microglia, neuron and endotheliocyte were sources of Gal-3 in cortex area; astrocyte, microglia and endotheliocyte were sources of Gal-3 in thalamus area; oligodendrocyte precursor cell and endotheliocyte were sources of Gal-3 in corpus callosum; neuron, microglia and endotheliocyte were sources of Gal-3 in hippocampus. In conclusion, we demonstrated spatiotemporal expression patterns of Galectin-3 post perinatal hypoxic-ischemic brain injury in this research.

19.
Proc Natl Acad Sci U S A ; 116(36): 17673-17682, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31427507

RESUMO

Nuclear energy development has entered an unexpected second nuclear era, which is mainly driven by developing countries. Despite major efforts to pursue a safe nuclear energy system in the first nuclear era, severe nuclear accidents occurred. A basic problem is that we do not have an adequate understanding of nuclear safety. From the viewpoints of risk and the close coupling of technical and social factors, this paper reexamines the nature of nuclear safety and reviews how previous experts understood it. We also highlight the new challenges that we are likely to confront in the unexpected second nuclear era and clarify some of the refinements that need to be made to the concept of nuclear safety from a sociotechnical perspective. These include the following: 1) Risk decisions should be made based on integrating social and technical elements (i.e., "social rationality"); 2) risk needs to be controlled based on the "Wuli-Shili-Renli" framework; 3) systems thinking should be substituted for reductionism in risk assessment, and social mechanisms need to be combined to address uncertainties; and 4) public-centered risk communication should be established. This contribution can provide a theoretical foundation for improving our understanding of the nature of nuclear safety and for transforming the concept of nuclear safety in the unexpected second nuclear era.

20.
J Mater Sci Mater Med ; 30(8): 91, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31388766

RESUMO

Customized porous titanium alloys have become the emerging materials for orthopaedic implant applications. In this work, diamond and rhombic dodecahedron porous Ti-33Nb-4Sn scaffolds were fabricated by selective laser melting (SLM). The phase, microstructure and defects characteristics were investigated systematically and correlated to the effects of pore structure, unit cell size and processing parameter on the mechanical properties of the scaffolds. Fine ß phase dendrites were obtained in Ti-33Nb-4Sn scaffolds due to the fast solidification velocity in SLM process. The compressive and bending strength of the scaffolds decrease with the decrease of strut size and diamond structures showed both higher compressive and bending strength than the dodecahedron structures. Diamond Ti-33Nb-4Sn scaffold with compressive strength of 76 MPa, bending strength of 127 MPa and elastic modulus of 2.3 GPa was achieved by SLM, revealing the potential of Ti-33Nb-4Sn scaffolds for applications on orthopaedic implant.

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