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Recently, open tubular capillary electrochromatography (OT-CEC) has captured considerable interest; its efficient separation capability hinges on the interactions between analytes and polymer coatings. However, in situ growth of stimuli-responsive polymers as coatings has been rarely studied and is crucial for expanding the OT-CEC technique and its application. Herein, following poly(styrene-maleicanhydride) (PSM) chemically bonded onto the inner surface of the capillary, a dual pH/temperature stimuli-responsive block copolymer, P(SMN-COOH), was prepared by in situ polymerizing poly(N-isopropylacrylamide) carboxylic acid terminated [P(N-COOH)] in PSM. An OT-CEC protocol was first explored using the coated capillary for epimedins separation. As a proof of concept, the developed OT-CEC system facilitated hydrogen bonding and tuning the hydrophilic/hydrophobic interactions between the test analytes and the P(SMN-COOH) coating by varying buffer pH and environmental temperature. Four epimedins with similar chemical structures were baseline separated under 40 °C at pH 10.0, exhibiting dramatical improvement in separation efficiency in comparison to its performance under 25 °C at pH 4.0. In addition, the coated capillary showed good repeatability and reusability with relative standard deviations for migration time and peak area between 0.7 and 1.7% and between 2.9 and 4.6%, respectively, and no significant changes after six runs. This work introduces a paradigm for efficient OT-CEC separation of herbal medicines through adjusting the interactions between analytes and smart polymer coatings, addressing polymer coating design and OT-CEC challenges.
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Objective To investigate the frequency and distribution characteristics of gene mutations in children with phenylalanine hydroxylase(PAH)deficiency in Xinjiang.Methods A total of 230 children diag-nosed with PAH deficiency in Urumqi Maternal and Child Health Care Hospital from January 1st,2015 to February 28th,2023 were enrolled in the study.The variation of PAH gene was analyzed and the variation sites of PAH gene in children with different phenotypes were compared.Results A total of 441 PAH gene va-riants were detected in 230 children with PAH deficiency in Xinjiang,with a total detection rate of 95.87%.A-mong them,2 variants were detected in 227 cases,only 1 variant was detected in 2 cases,and 3 variants were detected in 1 case.217 cases were complex heterozygous variants,and 10 cases were homozygous variants.The high-frequency variant loci were c.158G>A[23.39%(102/441)],c.728G>A[11.70%(51/441)],c.688G>A[5.05%(22/441)],c.721C>T[3.90%(17/441)],c.611A>G[3.67%(16/441)],c.1238G>C[3.21%(14/441)].The high-frequency variant loci for classic PKU were c.728G>A,c.331C>T,and c.782G>A;the high-frequency variant loci for mild PKU were c.721C>T,c.1068C>A,and c.1301C>A;the high-frequency variant loci for children with mild HPA were c.158G>A and c.688G>A.There were significant differences in the frequency of high frequency mutations among the above three phenotypes(P<0.05).Conclusion Mild HPA predominates in children with PAH deficiency in Xinjiang.The hotspot loci of the PAH gene in Xinjiang have been clarified,and specific PAH gene loci have been observed in the three different phenotypes,which can provide theoretical basis for prenatal diagnosis and clinical genetic counselling.
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Objective To quickly observe the tonic effects of Cervi Colla on enriching blood,strengthening bones and anti-aging in zebrafish model.Methods Glyphosate(Gly)was used to construct the erythrocyte injury model in adult zebrafish,and methotrexate(MTX)was used to construct the hematopoietic function injury model of juvenile zebrafish.Prednisolone(Pred)was used to establish the inhibition model of bone formation in zebrafish larvae.The ocular cell apoptosis model of zebrafish larvae was established by dibutyl phthalate(DBP).Results Cervi Colla could improve the Gly-induced abnormal erythrocyte nucleus in adult zebrafish and promote the expression of hematopoietic factors SCL and GATA1.Cervi Colla improved Pred-induced inhibition of bone formation in juvenile zebrafish,and promoted the expression of osteoblast-related gene ALP and Runx2a.The number of ocular cell apoptosis induced by DBP was decreased,and the expression of anti-apoptotic factor Bcl-2 was promoted.Conclusion Cervi Colla has significant effects on protecting erythrocyte,protecting hematopoiesis,protecting bone formation and anti-apoptosis.These effects may be related to replenish blood,anti-osteoporosis,and anti-aging.This study provides a scientific basis for the clinical application of Cervi Colla,and lays a foundation for further development and application.
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Objective:To investigate frailty in older patients with comorbidities and explore related risk factors.Methods:A cross-sectional study was conducted with an enrollment of 746 patients aged 65 years or older with comorbidities in the Wanshoulu Road area of Beijing from April 2019 to December 2020.A total of 617 patients with comorbidities were finally included, aged(85.6±4.8)years, including 358 women(58.0%); According to the FRAIL scale, 617 patients with comorbidities were divided into a frail group(156 cases, 25.3%)and a non-frail group(461 cases, 74.7%). Demographic data and information on comorbidities were collected.Univariate and multivariate Logistic regression analyses of risk factors were conducted.Results:Among 617 patients with comorbidities, the common chronic diseases in descending order were hypertension(497 cases, 80.6%), coronary heart disease(375 cases, 60.8%), osteoporosis(357 cases, 57.9%), osteoarthritis(281 cases, 45.5%), type 2 diabetes(211 cases, 34.2%), stroke and/or transient ischemic attack(193 cases, 31.3%), chronic lung disease(144 cases, 23.3%), tumor(133 cases, 21.6%), chronic kidney disease(92 cases, 14.9%), and heart failure(58 cases, 9.4%). Univariate logistic regression analysis showed that age, type 2 diabetes, coronary heart disease, heart failure, chronic lung disease, stroke/transient ischemic attack, cancer and osteoarthritis were influencing factors for frailty( P<0.05). Multivariate logistic regression analysis showed that age, type 2 diabetes, heart failure, chronic lung disease, cancer and osteoarthritis were risk factors for frailty( OR=1.076, 1.806, 3.275, 3.371, 1.640, 2.227, all P<0.05). Conclusions:Old age, type 2 diabetes, heart failure, chronic lung disease, tumor and osteoarthritis are closely related to frailty in elderly patients with comorbidities.Proactive and effective prevention and intervention should be instituted to target risk factors for frailty to reduce the occurrence of adverse outcomes.
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Neuroplastin 65 (Np65) is an immunoglobulin superfamily cell adhesion molecule involved in synaptic formation and plasticity. Our recent study showed that Np65-knockout (KO) mice exhibit abnormal cognition and emotional disorders. However, the underlying mechanisms remain unclear. In this study, we found 588 differentially-expressed genes in Np65-KO mice by microarray analysis. RT-PCR analysis also revealed the altered expression of genes associated with development and synaptic structure, such as Cdh1, Htr3a, and Kcnj9. In addition, the expression of Wnt-3, a Wnt protein involved in development, was decreased in Np65-KO mice as evidenced by western blotting. Surprisingly, MRI and DAPI staining showed a significant reduction in the lateral ventricular volume of Np65-KO mice. Together, these findings suggest that ablation of Np65 influences gene expression, which may contribute to abnormal brain development. These results provide clues to the mechanisms underlying the altered brain functions of Np65-deficient mice.
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Animales , Síntomas Afectivos , Metabolismo , Encéfalo , Diagnóstico por Imagen , Metabolismo , Patología , Trastornos del Conocimiento , Metabolismo , Expresión Génica , Imagen por Resonancia Magnética , Glicoproteínas de Membrana , Genética , Fisiología , Ratones Noqueados , Análisis por Micromatrices , Tamaño de los Órganos , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteína Wnt3 , MetabolismoRESUMEN
SARS-CoV-2 spike protein (S) is structurally dynamic and has been observed by cryo-EM to adopt a variety of prefusion conformations that can be categorized as locked, closed and open. The locked conformations feature tightly packed trimers with structural elements incompatible with RBD in "up" position. For SARS-CoV-2 S, it has been shown that the locked conformations are transient under neutral pH. Probably due to their transience, locked conformations remain largely uncharacterized for SARS-CoV-1 S. Intriguingly, locked conformations were the only conformations captured for S proteins of bat and pangolin origin SARS-related coronaviruses. In this study, we introduced x1, x2, and x3 disulfides into SARS-CoV-1 S. Some of these disulfides have been shown to preserve rare locked conformations when introduced to SARS-CoV-2 S. Introduction of these disulfides allowed us to image a variety of locked and other rare conformations for SARS-CoV-1 S by cryo-EM. We identified bound cofactors and structural features that are associated with SARS-CoV-1 S locked conformations. We compare newly determined structures to other available spike structures of Sarbecoviruses to identify conserved features and discuss their possible functions.
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The COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 has led to accelerated efforts to develop therapeutics, diagnostics, and vaccines to mitigate this public health emergency. A key target of these efforts is the spike (S) protein, a large trimeric class I fusion protein that is metastable and difficult to produce recombinantly in large quantities. Here, we designed and expressed over 100 structure-guided spike variants based upon a previously determined cryo-EM structure of the prefusion SARS-CoV-2 spike. Biochemical, biophysical and structural characterization of these variants identified numerous individual substitutions that increased protein yields and stability. The best variant, HexaPro, has six beneficial proline substitutions leading to [~]10-fold higher expression than its parental construct and is able to withstand heat stress, storage at room temperature, and multiple freeze-thaws. A 3.2 [A]-resolution cryo-EM structure of HexaPro confirmed that it retains the prefusion spike conformation. High-yield production of a stabilized prefusion spike protein will accelerate the development of vaccines and serological diagnostics for SARS-CoV-2.
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Three pathogenic human coronaviruses have emerged within the last 20 years, with SARS-CoV-2 causing a global pandemic. Although therapeutic antibodies targeting the SARS-CoV-2 spike currently focus on the poorly conserved receptor-binding domain, targeting essential neutralizing epitopes on the more conserved S2 domain may provide broader protection. We report an antibody binding an epitope conserved in the pre-fusion core of MERS-CoV, SARS-CoV and SARS-CoV-2 spike S2 domains. Antibody 3A3 binds a conformational epitope with ~2.5 nM affinity and neutralizes spike from SARS-CoV, SARS-CoV-2 and variants of concern in in vitro pseudovirus assays. Hydrogen-deuterium exchange mass spectrometry identified residues 980-1006 in the flexible hinge region at the S2 apex as the 3A3 epitope, suggesting 3A3 prevents the S2 conformational rearrangements required for conversion to the spike post-fusion state and virus-host cell fusion. This work defines a conserved vulnerable site on the SARS-CoV-2 S2 domain and guides the design of pan-protective spike immunogens.