Elucidating the mechanism of nucleation inhibition of pathology crystallization of gout based on the evidence from amorphous form and in solution

The first gout attack in a hyperuricaemic patient may be regarded as a nucleation event which is caused by monosodium urate monohydrate (MSUM) deposition in the synovial fluid. The effect of Tailor-Made Inhibition (TMI) may be effective as drugs for the prevention of aberrant nucleation and crystallization. Therefore, the understanding of the underlying mechanisms in inhibiting the MSUM nucleation by TMI has proven to be of great significance. Yet most of the published studies about nucleation inhibition have tended to focus on simpler molecular models with a hydrogen-bonded acceptor and donor, which may be not suitable for the uric acid molecule with multiple hydrogen-bonded acceptors and donors under physiological conditions. Herein, the mechanisms of nucleation inhibition of MSUM were explored in a simulated biological environment (0.15 M Na⁺ and pH 7.40) in the presence and absence of TMI. And the evidence of nucleation inhibition by TMI in solution and the amorphous form of MSUM was investigated by HNMR, IR, Raman, PXRD, Dynamic light scattering (DLS), induction time measurements, and density functional theory (DFT) calculations. Results showed that the inhibition comes from a combination of kinetic and thermodynamic effects, with an impact of kinetics as the TMI inhibition effects far exceeded what could be accounted for by changes in usual factors of classical nucleation theory. The data demonstrated that the complex between urate and TMI disturbed the formation of two-dimensional sheets of sodion and purine rings parallel to the (011) plane and further impeded the formation of a three-dimensional structure with aromatic stacking interactions in solution. To our knowledge, the nucleation inhibition of TMI is achieved by suppressing interplanar stacking, which is a mechanism proposed for the first time.

Xanthine, a tailor-made inhibitor, could suppress nucleation in the crystallization of gout pathology by blocking the dominant interplanar accumulation in a solution.     

Haploidentical hematopoietic stem cell transplantation may improve long-term survival for children with high-risk T-cell acute lymphoblastic leukemia in first complete remission

Background: The role of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children with high-risk (HR) T-cell acute lymphoblastic leukemia (T-ALL) in first complete remission (CR1) is still under evaluation. Moreover, relapse is the main factor affecting survival. This study aimed to explore the effect of allo-HSCT (especially haploidentical HSCT [haplo-HSCT]) on improving survival and reducing relapse for HR childhood T-ALL in CR1 and the prognostic factors of childhood T-ALL in...     

Risk of infections of biological and targeted drugs in patients with spondyloarthritis: meta-analysis of randomized clinical trials

Background: Concerns exist regarding the risk of infections in patients with spondyloarthritis (SpA) treated with biologics. We assessed the risk of infections of biological and targeted drugs in patients with SpA by performing a meta-analysis based on randomized controlled trials (RCTs).Methods: A systematic literature search was conducted in PubMed, Embase, Web of Science, the Cochrane Library, and China Biology Medicine Disc for RCTs evaluating the risk of infections of biological therapy in ...     

Leflunomide therapy for adult patients with steroid-dependent minimal change disease or primary focal segmental glomerulosclerosis

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Mixed invasive pulmonary Mucor and Aspergillus infection: a case report and literature review

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Natural killer cells in obstetric antiphospholipid syndrome

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卵黄样黄斑营养不良基因三个新的点突变与散发性Best病表现型关系的分析

Best病又称Best卵黄样黄斑营养不良(BVMD),是一种不规则的常染色体显性遗传性疾病,也有一些散发病例;临床特征是幼年或青年时期双眼黄斑部视网膜出现卵黄状的脂质样沉积物,而视力一般不受影响.随着病情发展,卵黄样物质逐渐吸收,开始出现视力波动.患者常在40岁左右时常发展为视网膜色素上皮(RPE)萎缩,黄斑部视网膜纤维瘢痕形成,以及继发性脉络膜新生血管(CNV)形成和视网膜下出血,最终出现视力严重的不可逆性损害.     

医院用药经济分析的基本方法

本文简要介绍了医院药品经济分析的基本方法，包括购药分析、处方分析、质量控制和相关文献。     

Pharmacokinetics,biodistribution and bioavailability of isoliquiritigenin after intravenous and oral administration

Context: Isoliquiritigenin (ISL) has been shown to exhibit a variety of biological activities. However, there is little research on the pharmacokinetic behavior and tissues distribution of ISL.

Objective: Pharmacokinetics, biodistribution and bioavailability of ISL after intravenous and oral administration were determined by systematic investigation in Sprague–Dawley rats.

Materials and methods: ISL was dissolved in medicinal ethanol-Tween 80–0.9% sodium chloride saline in a volume ratio of 10:15:75. The ISL solution was injected in rats via a tail vein at a single dose of 10, 20 and 50?mg/kg and administered orally in rats at a single dose of 20, 50 and 100?mg/kg, respectively. Blood samples were collected at time intervals of 0.08, 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 6, 8 and 12?h after intravenous injection. Tissues of interests in mice were collected immediately at each determined time point (0.5, 1, 2, 3 and 6?h) after cervical dislocation.

Results: The dose-normalized AUC values were 7.3, 7.6 and 8.7?μg?×?h/ml (calculated based on the dose of 10?mg/kg) for intravenous doses of 10, 20 and 50?mg/kg, respectively. The elimination half-lifes (t_1/2λ) were 4.9, 4.6 and 4.8?h at 10, 20 and 50?mg/kg intravenous doses, respectively. The F values were 29.86, 22.70, 33.62% for oral doses of 20, 50 and 100?mg/kg, respectively. Liver, heart and kidney were major distribution tissues of ISL in mice. The plasma protein binding of ISL in rats was 43.72%.

Conclusion: The work may useful for further study of the bioactive mechanism of ISL.