20 research outputs found

    Application of adsorptive stripping differential pulse voltammetry with chemometrics in the determination of ascorbic acid, rutin and quercetin in the food and health products

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    914-922The simultaneous determination of ascorbic acid, rutin and quercetin in the food and health products on the glassy carbon electrode have been investigated by adsorptive stripping differential pulse voltammetry (AdSDPV) with the aid of chemometrics. In the pH 5.2 KH2PO4 – Na2HPO4 buffer solution, both rutin and quercetin has shown a pair of sensitive reversible oxidation-reduction peak, while ascorbic acid only has shown an irreversible oxidation peak on the glassy carbon electrode. In the range of 0.35-0.50 V, the vlotammograms of three components has shown serious overlap with peak potential of ascorbic acid, rutin and quercetin. So, it is extremely difficult to realize direct measurement for the content of single component. Chemometrics methods have been introduced to determine the admixture of the three components. In this way, we have avoided the troublesome procedures of separation and purification, and assay the artificial compound of the three components all at once. We have estimated the three components in the food and the health products with satisfactory results

    Utilization of multiple genetic methods for prenatal diagnosis of rare thalassemia variants

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    Background: Thalassemia is the most prevalent monogenic disorder caused by an imbalance between the α- and β-globin chains as a result of pathogenic variants in the α- or β-globin genes. Novel or complex structural changes in globin genes are major hurdles for genetic consulting and prenatal diagnosis.Methods: From 2020 to 2022, genetic analysis was performed on 1,316 families suspected of having children with thalassemia major, including 42 pregnant couples suspected of being thalassemia carriers with rare variants. Multiple techniques including multiplex ligation-dependent probe amplification (MLPA), Sanger sequencing, targeted next-generation sequencing, and single-molecule real-time (SMRT) sequencing were used to diagnose rare thalassemia.Results: The rate of prenatal diagnosis for rare thalassemia variants was 3.19% (42/1,316). The most prevalent alleles of α- and β-thalassemia are Chinese Gγ(Aγδβ)0and -- THAI deletion. In addition, ten rare complex genotypes include one Chinese Gγ(Aγδβ)0 deletion combined with HBG1-HBG2 fusion, two rare deletions at HBB gene (hg38, Chr11: 5224211-5232470, hg38, Chr11: 5224303-5227790), one complete 7,412 bp fusion gene for anti-Lepore Hong Kong, two complex rearrangements of the α-globin gene cluster, two novel duplications, and two rare large deletions in the α-globin gene cluster.Conclusion: Accurate gene diagnosis for probands with combined molecular biology techniques is the key to prenatal diagnosis of rare thalassemia

    Crystal structure of triple-BRCT-domain of ECT2 and insights into the binding characteristics to CYK-4

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    AbstractHomo sapiens ECT2 is a cell cycle regulator that plays critical roles in cytokinesis. ECT2 activity is restrained during interphase via intra-molecular interactions that involve its N-terminal triple-BRCT-domain and its C-terminal DH–PH domain. At anaphase, this self-inhibitory mechanism is relieved by Plk1-phosphorylated CYK-4, which directly engages the ECT2 BRCT domain. To provide a structural perspective for this auto-inhibitory property, we solved the crystal structure of the ECT2 triple-BRCT-domain. In addition, we systematically analyzed the interaction between the ECT2 BRCT domains with phospho-peptides derived from its binding partner CYK-4, and have identified Ser164 as the major phospho-residue that links CYK-4 to the second ECT2 BRCT domain

    Cryptotanshinone-Loaded Cerasomes Formulation: In Vitro Drug Release, in Vivo Pharmacokinetics, and in Vivo Efficacy for Topical Therapy of Acne

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    Cerasomes (CS), evolved from liposomes, are novel drug-delivery systems that have potential medical application as carriers for drugs or active ingredients. Although many studies have been conducted on the pharmaceutical and physicochemical properties of CS, the role of CS in influencing the in vivo plasma and topical pharmacokinetics and efficacy of topical drug delivery remain unclear. In this context, we chose cryptotanshinone (CTS) as a model drug for the preparation of CTS-CS by means of the ethanol injection method to investigate their in vitro/in vivo drug-release behavior and in vivo efficacy. (1) In in vitro studies, CTS-CS gel was proven to be capable of achieving a higher permeation rate and significant accumulation in the dermis of isolated rat skin using Franz diffusion cells. (2) In in vivo studies, microdialysis experiments used to measure the plasma and topical pharmacokinetics demonstrated that the CS had a high drug concentration, short peak time, and slow elimination. Meanwhile, the plasma area under the concentration–time curve of CTS-CS gel was less than half that for the CTS gel in 12 h, which indicates that the drug bioavailability dramatically increased in the experiments. (3) In in vivo efficacy studies, we duplicated a rat acne model and performed antiacne efficacy experiments. The CTS-CS gel improved the antiacne efficacy compared to that of ordinary CTS gel. Moreover, it inhibited the expression of interleukin-1α and androgen receptors effectively. All of these results show that CTS-CS gel has significant potential for the treatment of acne induced by inflammation and excessive secretion of androgen, suggesting that CS formulations were designed as a good therapeutic option for skin disease
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