204 research outputs found

    Blind spheres of paramagnetic dopants in solid state NMR

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    Solid-state NMR on paramagnetically doped crystal structures gives information about the spatial distribution of dopants in the host. Paramagnetic dopants may render NMR active nuclei virtually invisible by relaxation, paramagnetic broadening or shielding. In this contribution blind sphere radii r(0) have been reported, which could be extracted through fitting the NMR signal visibility function f (x) = exp(-ar(0)(3)x) to experimental data obtained on several model compound series: La(1-x)Ln(x)PO(4) (Ln = Nd, Sm, Gd, Dy, Ho, Er, Tm, Yb), Sr1-xEuxGa2S4 and (Zn1-xMnx)(3)(PO4)(2)center dot 4H(2)O. Radii were extracted for H-1, P-31 and Ga-71, and dopants like Nd3+, Gd3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+ and Mn2+. The observed radii determined differed in all cases and covered a range from 5.5 to 13.5 angstrom. While these radii were obtained from the amount of invisible NMR signal, we also show how to link the visibility function to lineshape parameters. We show under which conditions empirical correlations of linewidth and doping concentration can be used to extract blind sphere radii from second moment or linewidth parameter data. From the second moment analysis of La1-xSmxPO4 P-31 MAS NMR spectra for example, a blind sphere size of Sm3+ can be determined, even though the visibility function remains close to 100% over the entire doping range. Dependence of the blind sphere radius r(0) on the NMR isotope and on the paramagnetic dopant could be suggested and verified: for different nuclei, r(0) shows a 3 root gamma-dependence, gamma being the gyromagnetic ratio. The blind sphere radii r(0) for different paramagnetic dopants in a lanthanide series could be predicted from the pseudo-contact term

    Effects of Oral Administration of Encapsulated-Leucine on Amino (uji plagiasi)

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    Background And Objective: An abundantstud showthat leucine (Leu) acts as an anabolic agent that stimulates skeletal musce growth in human as well as in animals. Haver, the effect of encapsulated leucine (CL) supplementation on growth performance of broiler chickens has not been evaluated. Therefore, the aim of this study was to determine intlal metags responses to CL supplementation on food intake plan metabolites and branched chain amino acid concentration in 7-day-old broiler chicks. Materials and Methods: A total of 24 chicks were randomly assigned to the following treatments (1) Control 4 ) (2) Free leucine 4h iDand (3) Encapsulated leucine th (CL). After 6 Fasting, chicks were given a bolus of oral injection of distilled water, freel ne (6 mmol/10 ml.kg - BWor encapsulated-leucine (6 mmol/10 mt kg BW). Immediately after the injection, chicks were allowed free access to a commercialstarter diet for lh Blood collections were obtained after the oral injection Food intake total glucose total cholesterol, triacylglycerol, plasma leucine levels and the activity of glutamic oxaloacetic transaminase(GOT) were marred. Results: Food intake, glucose total cholesterol and triacylglycerol levels were not affected by Supplementation At 4 h, GOT levels were gre p .05)in the group than that were similar in all groups. Valine levels were lower (p<0.005) inthend Cl Groups of the groups At 4 h, although plasma leu os than that of thel.eu group and isoleucine levels were lower (p<0.001) in the group than that of the candle groups. Conclusion: The results of this study suggest that an oral administration of a caused prolonged leucine induced anabolics that may be beneficial for growth Our observations above the way for studying the long temeffects of supplementation performance of broiler chicks

    Emerging SARS-CoV-2 variants: Why, how, and what's next?

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    The emergence of the SARS-CoV-2 Omicron variant poses a striking threat to human society. More than 30 mutations in the Spike protein of the Omicron variant severely compromised the protective immunity elicited by either vaccination or prior infection. The persistent viral evolutionary trajectory generates Omicron-associated lineages, such as BA.1 and BA.2. Moreover, the virus recombination upon Delta and Omicron co-infections has been reported lately, although the impact remains to be assessed. This minireview summarizes the characteristics, evolution and mutation control, and immune evasion mechanisms of SARS-CoV-2 variants, which will be helpful for the in-depth understanding of the SARS-CoV-2 variants and policy-making related to COVID-19 pandemic control

    Market investigation of basic parameters for exposure assessment of contact materials for nut-seed food in China

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    Objective To establish the basic parameters for exposure assessment of contact materials for nut-seed food in China. Methods The contact area method was used to study the contact materials of nut-seed food in this study. Based on the contact area values, ratio of contact areas and unit mass were obtained. Results Through investigation and analysis, 114 kinds of nut-seed food were sampled, and 3 648 related data were obtained. Food contact materials of nut-seed food on the market mainly included aluminum, polyethylene, polyethylene terephthalate, polypropylene, polystyrene and coating. The average contact area per unit mass or volume (S/V) was 21.29 dm2/kg, the median was 13.40 dm2/kg, P5 was 1.11 dm2/kg, and P95 was 67.46 dm2/kg. Conclusion The basic parameters of nut-seed food contact materials could provide data support for the safety assessment in China

    Inflammatory bowel disease is causally related to irritable bowel syndrome: a bidirectional two-sample Mendelian randomization study

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    IntroductionInflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) are lifelong digestive diseases that severely impact patients’ quality of life. The existence of a causal association between IBS and IBD remains unclear. This study aimed to determine the direction of causality between IBD and IBS by quantifying their genome-wide genetic associations and performing bidirectional two-sample Mendelian randomization (MR) analyses.MethodsGenome-wide association studies (GWAS) among a predominantly European patient cohort identified independent genetic variants associated with IBS and IBD. Two separate databases (a large GWAS meta-analysis and the FinnGen cohort) for both IBS and IBD were consulted to retrieve statistics on instrument-outcome associations. MR analyses included inverse-variance-weighted, weighted-median, MR-Egger regression, MR Pleiotropy RESidual Sum and Outlier (MR-PRESSO) methods, and sensitivity analyses were performed. The MR analyses were carried out for each outcome data, followed by a fixed-effect meta-analysis.ResultsGenetically predicted IBD was associated with an increased risk of IBS. Odds ratios (95% confidence intervals) for samples of 211,551 (17,302 individuals with IBD), 192,789 (7,476 Crohn’s disease cases), and 201,143 (10,293 ulcerative colitis cases) individuals were 1.20 (1.00, 1.04), 1.02 (1.01, 1.03), and 1.01 (0.99, 1.03), respectively. After outlier correction using MR-PRESSO, the odds ratio for ulcerative colitis was 1.03 (1.02, 1.05) (p = 0.001). However, an association between genetically influenced IBS and IBD was not identified.DiscussionThis study confirms that IBD is causally related to IBS, which may interfere with the diagnosis and treatment of both diseases

    Prognostic values of ALDOB expression and 18F-FDG PET/CT in hepatocellular carcinoma

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    PurposeThe glycolytic enzyme fructose 1,6-bisphosphate aldolase B (ALDOB) is aberrantly expressed and impacts the prognosis in hepatocellular carcinoma (HCC). Hepatic ALDOB loss leads to paradoxical upregulation of glucose metabolism, favoring hepatocellular carcinogenesis. Nevertheless, the relationship between ALDOB expression and 18F-fluorodeoxyglucose (18F-FDG) uptake, and their effects on HCC prognosis remain unclear. We evaluated whether ALDOB expression is associated with 18F-FDG uptake and their impacts on HCC prognosis prediction.MethodsChanges in ALDOB expression levels and the prognostic values in HCC were analyzed using data from The Cancer Genome Atlas (TCGA) database. Ultimately, 34 patients with HCC who underwent 18F-FDG positron emission tomography/computed tomography (PET/CT) preoperatively were enrolled in this retrospective study. ALDOB expression was determined using immunohistochemistry (IHC) staining, and the maximum standardized uptake value (SUVmax) of HCC was calculated from the 18F-FDG PET/CT scans. The relationship between ALDOB expression and SUVmax was examined, and their impacts on overall survival were evaluated using Cox proportional hazards models and Kaplan–Meier survival analysis. ALDOB overexpression in HUH7 and 7721 cells was used to analyze its role in tumor metabolism.ResultsAccording to TCGA database, the ALDOB mRNA level was downregulated in HCC compared to normal tissue, and significantly shortened overall survival in HCC patients. ALDOB protein expression was similarly decreased in IHC findings in HCC than that in adjacent normal tissues (P&lt;0.05) and was significantly associated with tumor size (P&lt;0.001), high tumor-node-metastasis stage (P=0.022), and elevated SUVmax (P=0.009). ALDOB expression in HCC was inversely correlated with SUVmax (r=-0.454; P=0.012), and the optimal SUVmax cutoff value for predicting its expression was 4.15. Prognostically, low ALDOB expression or SUVmax ≥3.9 indicated shorter overall survival time in HCC. Moreover, COX regression analysis suggested high SUVmax as an independent prognostic risk factor for HCC (P=0.036). HCC patients with negative ALDOB expression and positive SUVmax (≥3.9) were correlated with worse prognosis. ALDOB overexpression in HCC cells significantly decreases 18F-FDG uptake and lactate production.ConclusionSUVmax in HCC patients is inversely correlated with ALDOB expression, and 18F-FDG PET/CT may be useful for ALDOB status prediction. The combined use of ALDOB expression and 18F-FDG PET/CT data can provide additional information on disease prognosis in HCC patients

    A long-term cohort study: the immune evasion and decreasing neutralization dominated the SARS-CoV-2 breakthrough infection

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    Most of vaccinees and COVID-19 convalescents can build effective anti-SARS-CoV-2 humoral immunity, which helps preventing infection and alleviating symptoms. However, breakthrough viral infections caused by emerging SARS-CoV-2 variants, especially Omicron subvariants, still pose a serious threat to global health. By monitoring the viral infections and the sera neutralization ability of a long-tracked cohort, we found out that the immune evasion of emerging Omicron subvariants and the decreasing neutralization led to the mini-wave of SARS-CoV-2 breakthrough infections. Meanwhile, no significant difference had been found in the infectivity of tested SARS-CoV-2 variants, even though the affinity between human angiotensin-converting enzyme 2 (hACE2) and receptor-binding domain (RBDs) of tested variants showed an increasing trend. Notably, the immune imprinting of inactivated COVID-19 vaccine can be relieved by infections of BA.5.2 and XBB.1.5 variants sequentially. Our data reveal the rising reinfection risk of immune evasion variants like Omicron JN.1 in China, suggesting the importance of booster with updated vaccines

    Aloperine Suppresses Cancer Progression by Interacting with VPS4A to Inhibit Autophagosome-lysosome Fusion in NSCLC.

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    Aloperine (ALO), a quinolizidine-type alkaloid isolated from a natural Chinese herb, has shown promising antitumor effects. Nevertheless, its common mechanism of action and specific target remain elusive. Here, it is demonstrated that ALO inhibits the proliferation and migration of non-small cell lung cancer cell lines in vitro and the tumor development in several mouse tumor models in vivo. Mechanistically, ALO inhibits the fusion of autophagosomes with lysosomes and the autophagic flux, leading to the accumulation of sequestosome-1 (SQSTM1) and production of reactive oxygen species (ROS), thereby inducing tumor cell apoptosis and preventing tumor growth. Knockdown of SQSTM1 in cells inhibits ROS production and reverses ALO-induced cell apoptosis. Furthermore, VPS4A is identified as a direct target of ALO, and the amino acids F153 and D263 of VPS4A are confirmed as the binding sites for ALO. Knockout of VPS4A in H1299 cells demonstrates a similar biological effect as ALO treatment. Additionally, ALO enhances the efficacy of the anti-PD-L1/TGF-β bispecific antibody in inhibiting LLC-derived subcutaneous tumor models. Thus, ALO is first identified as a novel late-stage autophagy inhibitor that triggers tumor cell death by targeting VPS4A

    Between now and later: a mixed methods study of HPV vaccination delay among Chinese caregivers in urban Chengdu, China

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    BACKGROUND: Adolescent girls in China have a low HPV vaccination rate. Although vaccination is recommended by the Chinese health authorities, the cost is not covered by the national immunisation programme. Vaccination delay, among other reasons such as supply shortage and poor affordability, may contribute to low uptake. This sequential mixed methods study aimed to identify potential factors of delayed HPV vaccination among Chinese adolescent girls. METHODS: Quantitative data about the attitudes and perceptions of HPV vaccination were collected from 100 caregivers of 14-18-year-old girls using an online survey in Chengdu, China. The survey data informed a subsequent qualitative study using four focus group discussions. We conducted a descriptive analysis of the survey data and a thematic analysis of the qualitative data. The findings were interpreted using a health behaviour model adapted from the Health Belief Model and the Andersen's Behavioural Model for Health Services Use. RESULTS: A total of 100 caregivers - 85 were mothers and 15 were fathers - participated in the survey; 21 caregivers joined focus group discussions. When asked about their intended course of action if the 9vHPV vaccine was out-of-stock, 74% chose to delay until the 9vHPV vaccine is available while 26% would consider 2vHPV or 4vHPV vaccines or seek alternative ways to procure the vaccine. Qualitative results confirmed that caregivers preferred delaying HPV vaccination for adolescent girls. The intent to delay was influenced by systemic barriers such as supply shortage and individual-level factors such as a preference for the 9vHPV vaccine, safety concerns, inadequate health communication, and the belief that adolescents were unlikely to be sexually active. CONCLUSION: In urban areas, Chinese caregivers' intent to delay vaccination in favour of 9vHPV vaccine over receiving the more accessible options was influenced by a mix of individual and contextual factors. Focussed health communication strategies are needed to accelerate HPV vaccination among adolescents
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