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Encapsulating metal nanoparticles inside carbon layers is a promising approach to simultaneously improving the activity and stability of electrocatalysts. The role of carbon layer shells, however, is not fully understood. Herein, we report a study of boron doped carbon layers coated on nickel nanoparticles (Ni@BC), which were used as a model catalyst to understand the role of a bridging oxygen in a carbon shell coated Ni interface for the improvement of the hydrogen oxidation reaction (HOR) activity using an alkaline electrolyte. Combining experimental results and density functional theory (DFT) calculations, we find that the electronic structure of Ni can be precisely tailored by Ni-O-C and Ni-O-B coordinated environments, leading to a volcano type correlation between the binding ability of the OH* adsorbate and HOR activity. The obtained Ni@BC with a optimized d-band center displays a remarkable HOR performance with a mass activity of 34.91 mA mgNi-1, as well as superior stability and CO tolerance. The findings reported in this work not only highlight the role of the OH* binding strength in alkaline HOR but also provide guidelines for the rational design of advanced carbon layers used to coat metal electrocatalysts.

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Developing high-performance electrocatalysts for alkaline hydrogen oxidation reaction (HOR) is crucial for the commercialization of anion exchange membrane fuel cells (AEMFCs). Here, boron interstitially inserted ruthenium (B-Ru/C) is synthesized and used as an anode catalyst for AEMFC, achieving a peak power density of 1.37 W cm-2 , close to the state-of-the-art commercial PtRu catalyst. Unexpectedly, instead of the monotonous decline of HOR kinetics with pH as generally believed, an inflection point behavior in the pH-dependent HOR kinetics on B-Ru/C is observed, showing an anomalous behavior that the HOR activity under alkaline electrolyte surpasses acidic electrolyte. Experimental results and density functional theory calculations reveal that the upshifted d-band center of Ru after the intervention of interstitial boron can lead to enhanced adsorption ability of OH and H2 O, which together with the reduced energy barrier of water formation, contributes to the outstanding alkaline HOR performance with a mass activity of 1.716 mA µgPGM -1 , which is 13.4-fold and 5.2-fold higher than that of Ru/C and commercial Pt/C, respectively.

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BACKGROUND: This study was to explore the association between dietary polyunsaturated fatty acids (PUFAs) consumption and cardiovascular diseases (CVDs), all-cause mortality, and CVD-specific mortality. METHODS: This retrospective cohort study extracted demographic and clinical data of 38,838 adult participants from the National Health and Nutrition Examination Survey (NHANES) database in 2003-2018. We explored the association between octadecadienoic acid (ODA), octadecatrienoic acid (ALA), octadecatetraenoic acid (ODTA), eicosatetraenoic acid (AA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA) and different CVDs using weighted univariate and multivariate logistic regression analyses with odds ratio (OR) and 95% confidence interval (CI). The PUFAs were divided into four levels according to the quartiles (≤ Q1, Q1 to Q2, Q1 to Q2, > Q3). Weighted univariate and multivariate COX regression analyses with hazard ratio (HR) and 95% CI were used for exploring the association between PUFAs and all-cause mortality, CVD-specific mortality and other cause-specific mortality. RESULTS: During the follow-up, a total of 4,908 (9.12%) eligible participants died. The results showed that after adjusting for covariates, ODTA intake was related to low odds of coronary heart disease (CHD) [OR = 0.75, 95%CI: (0.64-0.88)]. Q1-Q2 quartile of ALA [OR = 0.81, 95%CI: (0.66-0.99)] and Q2-Q3 quartile of DPA [OR = 0.78, 95%CI: (0.62-0.99)] intakes were linked to low odds of heart attack, and > Q3 quartile of ODA intake was associated with low odds of congestive heart failure (CHF) [OR = 0.66, 95%CI: (0.49-0.90)] and stroke [OR = 0.65, 95%CI: (0.47-0.90)]. Q2-Q3 quartile of DPA intake was linked to low odds of angina [OR = 0.76, 95%CI: (0.58-0.99)]. Higher ALA intake was associated with a lower risk of all-cause mortality [Q2-Q3: HR = 0.86, 95%CI: (0.74-0.99); > Q3: HR = 0.76, 95%CI: (0.63-0.91)]. Additionally, Q2-Q3 quartile of ALA, Q1-Q2 quartile of AA and DPA intakes were respectively related to a low risk of CVD-specific mortality, while that > Q3 quartile of ALA related to that of mortality by other causes. CONCLUSION: Our study found that PUFAs were associated with different CVDs, and higher ALA intake was related to lower risk of all-cause mortality. Ensuring adequate intake of PUFAs was beneficial to the health and may decrease the risk of mortality.

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In order to curve the ongoing trend of the COVID-19 pandemic and save more lives, effective treatments against COVID-19 are urgently needed. Compared to developing new drugs, which may take too much time, it's more efficient and cost-effective to repurpose existing drugs in the treatment of COVID-19. Fortunately, some of the shared features of COVID-19 and other wellknown diseases make it possible to use old strategies to combat this new challenge. In this paper, we reviewed various possible strategies of drug repurposing in the treatment of COVID-19 and explored the possible scientific mechanisms behind each strategy.

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BACKGROUND: Reactivation of hepatitis B virus is a common complication that occurs in patients with hepatitis B virus (HBV) infection who have received cytotoxic chemotherapy or immunosuppressive therapy. This clinical phenomenon not only occurs in overt HBV infection patients but also occurs in patients with resolved HBV infection. Previous research has confirmed that epirubicin and dexamethasone can stimulate HBV replication and expression directly rather than indirectly through immunosuppression. Mitomycin and 5-fluorouracil are currently used as cytotoxic chemotherapy drugs for cancer patients. Leflunomide and mycophenolic acid are regarded as immunosuppressants for autoimmune diseases, and numerous clinical studies have reported that these drugs can reactivate HBV replication. In this study, we aimed to investigate whether mitomycin, 5-fluorouracil, leflunomide and mycophenolic acid induce HBV reactivation directly rather than indirectly through immunosuppression. METHODS: To observe the effect of mitomycin, 5-fluorouracil, leflunomide and mycophenolic acid on HBV replication and expression, we employed HepG2.2.15 and HBV-NLuc-35 cells as a cell model. Next, by native agarose gel electrophoresis (NAGE), quantitative PCR (qPCR), luciferase assay and HBV e antigen (HBeAg) enzyme-linked immunosorbent assay (ELISA) we detected changes in HBV replication and expression induced by these drugs. We also investigated whether lamivudine could inhibit the observed phenotype. SPSS 18.0 software was employed for statistical analysis, One-way ANOVA was used to compare multiple groups. RESULTS: Expression of HBV capsids and HBeAg in HepG2.2.15 cells was increased by increasing concentration of mitomycin, 5-fluorouracil, leflunomide, and mycophenolic acid. This phenomenon was also demonstrated in HBV-NLuc-35 cells, and the expression of capsids and luciferase activity increased in the same concentration-dependent manner. Replication levels of intracellular capsid DNA and extracellular HBV DNA in HepG2.2.15 cells gradually increased in a dose-dependent manner. In addition, although epirubicin, mitomycin, 5-fluorouracil, dexamethasone, leflunomide and mycophenolic acid enhanced HBV replication, lamivudine inhibited this process. CONCLUSION: Our study confirmed that mitomycin, 5-fluorouracil, leflunomide and mycophenolic acid directly upregulated HBV replication and expression in vitro. This effect was investigated not only in HepG2.2.15 cells but also in the HBV-NLuc-35 replication system. Moreover, this effect could be prevented by nucleoside analogs, such as lamivudine (LAM). Thus, for patients with HBV infection, prophylactic antiviral therapy is necessary before receiving cytotoxic chemotherapy or immunosuppressive therapy.

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Ni3B/Ni heterostructures have been constructed, which exhibit exceptional catalytic performance toward the hydrogen oxidation reaction (HOR) under alkaline media, with the mass activity being about 10 times greater than that of Ni3B and Ni, respectively, ranking among the most active platinum-group-metal-free electrocatalysts. Experimental results and theoretical calculations confirm electron transfer from Ni3B to Ni at the Ni3B/Ni interface, resulting in inter-regulated d-band centers of these two components. This inter-regulation gives rise to optimized binding energies of intermediates, which together contribute to enhanced alkaline HOR activity.

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BACKGROUND: Previously, we have successfully constructed replication-competent hepatitis B virus (HBV) vectors by uncoupling the P open reading frame (ORF) from the preC/C ORF to carefully design the transgene insertion site to overcome the compact organization of the HBV genome and maintain HBV replication competence. Consequently, the replication-competent HBV vectors carrying foreign genes, including pCH-BsdR, carrying blasticidin resistance gene (399 bp), and pCH-hrGFP, carrying humanized renilla green fluorescent protein gene (720 bp), were successfully obtained. However, the replication efficiency of the former is higher but it is tedious to use, while that of the latter is poor and cannot be quantified. Hence, we need to search for a new reporter gene that is convenient and quantifiable for further research. AIM: To establish a helpful tool for intracellular HBV replication and anti-viral drugs screening studies. METHODS: We utilized the replication-competent HBV viral vectors constructed by our laboratory, combined with the secreted luciferase reporter gene, to construct replication-competent HBV vectors expressing the reporter gene secretory Nanoluc Luciferase (SecNluc). HepG2.TA2-7 cells were transfected with this vector to obtain cell lines with stably secreted HBV particles carrying secNluc reporter gene. RESULTS: The replication-competent HBV vector carrying the SecNluc reporter gene pCH-sNLuc could produce all major viral RNAs and a full set of envelope proteins and achieve high-level secreted luciferase expression. HBV replication intermediates could be produced from this vector. Via transfection with pTRE-sNLuc and selection by hygromycin, we obtained isolated cell clones, named HBV-NLuc-35 cells, which could secrete secNLuc recombinant viruses, and were sensitive to existing anti-HBV drugs. Using differentiated HepaRG cells, it was verified that recombinant HBV possessed infectivity. CONCLUSION: Our research demonstrated that a replication-competent HBV vector carrying a secreted luciferase transgene possesses replication and expression ability, and the established HBV replication and expression cell lines could stably secrete viral particles carrying secNluc reporter gene. More importantly, the cell line and the secreted recombinant viral particles could be used to trace HBV replication or infection.

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BACKGROUND: Up until now, there are limited studies available on the epidemiology of infectious diseases in Democratic People's Republic of Korea (DPRK, North Korea). However, different types of infectious diseases have been found in North Korean travelers at Dandong port. Entry surveillance data of those North Korean travelers may provide some insight into the probable epidemiology of some infectious diseases in DPRK. METHODS: We actively analyzed the medical test result of North Korean travelers entering China through Dandong port. Detection of hepatitis B virus (HBV), tuberculosis (TB), syphilis and malaria was made by specific laboratory tests according to the national technical guidelines. Infectious diseases surveillance data for 2015-17 was analyzed and compared among subgroups. RESULTS: Between Jan 1, 2014, and Dec 31, 2016, 557 cases of infectious diseases were identified among 18,494 North Korean travelers, HBV active infection (466 cases), active TB infection (33 cases), current active syphilis infection (57) cases, Plasmodium falciparum (P.falciparum) malaria infection (1 case). The incidence of HBV, TB and syphilis in North Korean travelers was high. Incidence of TB increased from 11.7256 (1/10,000) in 2015 to 28.2738 (1/10,000) in 2017. HBV immunization rate in in North Korean travelers was relatively high in 0-10 age group. CONCLUSION: This report is the first to characterize the profile of infectious diseases among arriving North Korean travelers in mainland China. Our findings suggest high incidence of HBV, TB and syphilis among North Korean travelers. The screening for TB in North Korean workers should be strengthened in order to prevent infections imported into China.

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Periodontitis is an oral disease that is highly prevalent worldwide, with a prevalence of 30-50% of the population in developed countries, but only ~10% present with severe forms. It is also estimated that periodontitis results in worldwide productivity losses amounting to ~54 billion USD yearly. In addition to the damage it causes to oral health, periodontitis also affects other types of disease. Numerous studies have confirmed the association between periodontitis and systemic diseases, such as diabetes, respiratory disease, osteoporosis and cardiovascular disease. Increasing evidence also indicated that periodontitis may participate in the progression of liver diseases, such as non-alcoholic fatty liver disease, cirrhosis and hepatocellular carcinoma, as well as affecting liver transplantation. However, to the best of our knowledge, there are currently no reviews elaborating upon the possible links between periodontitis and liver diseases. Therefore, the current review summarizes the human trials and animal experiments that have been conducted to investigate the correlation between periodontitis and liver diseases. Furthermore, in the present review, certain mechanisms that have been postulated to be responsible for the role of periodontitis in liver diseases (such as bacteria, pro-inflammatory mediators and oxidative stress) are considered. The aim of the review is to introduce the hypothesis that periodontitis may be important in the progression of liver disease, thus providing dentists and physicians with an improved understanding of this issue.

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Reduction of reflection is of great importance in optical spectroscopy to reduce interference and increase throughput. Here we demonstrate a three-dimensional inverted photonic grating device design using only one material-silicon. Enhanced transmission compared to planar silicon wafers is observed from 0.2 THz to over 7.3 THz for a device with a 15 µm period, which covers most of the terahertz band, and its relative 3 dB bandwidth (δf/f(c)) is a noteworthy 116.3%. Moreover, the device is polarization independent and can perform up to a large incident angle.

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In the present paper, the authors report the characterization of multiwalled carbon nanotube at terahertz (THz) frequency range using terahertz time-domain spectroscopy. The surface appearances and microanalysis of multiwalled carbon nanotubes were measured by scanning electron microscope in order to fully understand the unique features and applications of multiwalled carbon nanotube. The results show that the refractive indexes of the sample decrease with increasing frequency in the frequency range of 0.2 to 2 THz, while the absorption coefficients of the sample increase with increasing frequency. In addition, the curve of terahertz absorption coefficients can be fitted by a straight line with a slope of 1.92. From the results of scanning electron microscope, the ranges of inner diameter and outer diameters of the sample were from 5 to 15 nm and from 15 to 25 nm, respectively, and its length was in the order of micrometer. The results of microanalysis of its elemental composition showed that the content of element C was about 94% and the rest were O and Cl elements, which were impurity elements. Mathematical modes of terahertz absorption and refractive indexes in the frequency range of 0.2 to 2.0 THz were established after taking into account Taylor expansion and Maxwell's equations, and the calculation was in relatively good agreement with the observed values of the sample in general. The terahertz refractive indexes and absorption properties of multiwalled carbon nanotube were mainly attributed to the chemical compositions and molecular weight, and carbon nanotubes with different content of carbon could show different terahertz absorption spectra and disclose different unique functions.