RESUMO
We report for the first time the use of experimental electron density (ED) in the Protein Data Bank for modeling of noncovalent interactions (NCIs) for protein-ligand complexes. Our methodology is based on reduced electron density gradient (RDG) theory describing intermolecular NCIs by ED and its first derivative. We established a database named Experimental NCI Database (ExptNCI; http://ncidatabase.stonewise.cn/#/nci) containing ED saddle points, indicating â¼200,000 NCIs from over 12,000 protein-ligand complexes. We also demonstrated the usage of the database in the case of depicting amide-π interactions in protein-ligand binding systems. In summary, the database provides details on experimentally observed NCIs for protein-ligand complexes and can support future studies including studies on rarely documented NCIs and the development of artificial intelligence models for protein-ligand binding prediction.
Assuntos
Inteligência Artificial , Elétrons , Bases de Dados de Proteínas , Ligantes , Substâncias MacromolecularesRESUMO
BACKGROUND: Dent disease is an X-linked form of progressive renal disease. This rare disorder was characterized by hypercalciuria, low molecular weight (LMW) proteinuria and proximal tubular dysfunction, caused by pathogenic variants in CLCN5 (Dent disease 1) or OCRL (Dent disease 2) genes. Fanconi syndrome is a consequence of decreased water and solute resorption in the proximal tubule of the kidney. Fanconi syndrome caused by proximal tubular dysfunction such as Dent disease might occur in early stage of the disease. CASE PRESENTATION: Three cases reported in this study were 3-, 10- and 14-year-old boys, and proteinuria was the first impression in all the cases. All the boys presented with LMW proteinuria and elevated urine albumin-to-creatinine ratio (ACR). Case 1 revealed a pathogenic variant in exon 11 of CLCN5 gene [NM_001127899; c.1444delG] and a nonsense mutation at nucleotide 1509 [p.L503*], and he was diagnosed as Dent disease 1. Case 2 carried a deletion of exon 3 and 4 of OCRL1 gene [NM_000276.4; c.120-238delG A] and a nonsense mutation at nucleotide 171 in exon 5 [p.E57*], and this boy was diagnosed as Dent disease 2. Genetic analysis of Case 3 showed a missense mutation located in exon 2 of HNF4A gene [EF591040.1; c.253C > T; p.R85W] which is responsible for Fanconi syndrome. All of three pathogenic variants were not registered in GenBank. CONCLUSIONS: Urine protein electrophoresis should be performed for patients with proteinuria. When patients have LMW proteinuria and/or hypercalciuria, definite diagnosis and identification of Dent disease and Fanconi syndrome requires further genetic analyses.
Assuntos
Doença de Dent/diagnóstico , Síndrome de Fanconi/diagnóstico , Adolescente , Criança , Pré-Escolar , Doença de Dent/complicações , Doença de Dent/genética , Síndrome de Fanconi/complicações , Síndrome de Fanconi/genética , Humanos , Masculino , Peso Molecular , Proteinúria/etiologiaRESUMO
Objective: Evaluate the technical performance of the pre-analytical hemolysis-icterus-lipemia (HIL) check module on the ACL-TOP-750. Methods: 8433 routine coagulation samples were evaluated for HIL, the presence of clotting and low sample volume by both visual inspection and the pre-analytical HIL check module on the ACL-TOP-750. Results: 7726 samples were in agreement with both methods and 707 were not consistent. 356 samples with low volume were identified by visual inspection and 920 by the instrument (2.7â mL threshold). Visual inspection identified 56 lipemic samples while 13 of those with moderate or high lipemia were identified by the instrument. Visual inspection identified 47 hemolyzed samples while 7 with moderate or high hemolysis were identified by the instrument. Both visual inspection and the instrument identified 36 icteric samples. For triglyceride concentration and bilirubin concentration, there was good correlation between the ACL-TOP-750 and the DXC800 biochemistry analyzer. Among 30 samples with varying amounts of clotting, 27 were discovered by visual inspection and 3 were discovered by the instrument. Conclusion: The pre-analytical check module on the ACL-TOP-750 improved the detection rate of samples below the target 2.7â mL volume, and the accuracy in detection of HIL. However, the automated method could not replace visual assessment of clotting in samples.
Assuntos
Hiperlipidemias , Icterícia , Testes de Coagulação Sanguínea/métodos , Hemólise , Hemostasia , HumanosRESUMO
Purpose: To evaluate the effects of a single oral dose of pyridoxine on lysine metabolites including α-aminoadipic semialdehyde (a-AASA), piperideine-6-carboxylate (P6C), the sum of AASA and P6C (AASA-P6C), pipecolic acid (PA), and α-aminoadipic acid (α-AAA) in PDE patients. Methods: The lysine metabolites of 15 patients with molecularly confirmed PDE were detected before and 4 h after taking a single oral dose of pyridoxine, respectively, using liquid chromatography-mass spectrometry (LC-MS/MS) method. Five types of samples were freshly prepared, including plasma, serum, dried blood spots (DBS), urine, and dried urine spots (DUS). Results: All the patients had been treated with long-term oral pyridoxine for several months to years, with doses of 30-360 mg/d. The concentrations of a-AASA, P6C, AASA-P6C, PA, and a-AAA before and after taking a single oral dose of pyridoxine for the same analyte detected in the same type of sample varied among patients. The mean concentrations increased in almost all the metabolites after taking an oral dose of pyridoxine, with or without statistical significance. Whereas, the metabolites concentrations might increase or decrease among different patients, or in different samples of the same patient, without a regular tendency. There was no statistical correlation between the concentrations before and after taking pyridoxine in the same type of sample for most metabolites. Conclusions: No obvious relationship between the metabolite levels or concentration differences and the age, pyridoxine dose (a single oral dose and long-term maintenance dose), duration of treatment, or neurodevelopmental phenotype was found at present study. The large individual differences among patients, probably affected by various genotypes, leading to quite different effects of pyridoxine on the change degree of metabolites concentrations. Our study suggested that long-term pyridoxine treatment could control seizures rather than getting toxic lysine metabolites such as a-AASA and P6C back to normal. In the future, more therapies should be focused to alleviate the metabolites accumulation and further improve the prognosis of PDE.
RESUMO
The measurements of lysine metabolites provide valuable information for the rapid diagnosis of pyridoxine-dependent epilepsy (PDE). Here, we aimed to develop a sensitive method to simultaneously quantify multiple lysine metabolites in PDE, including α-aminoadipic semialdehyde (a-AASA), piperideine-6-carboxylate (P6C), pipecolic acid (PA) and α-aminoadipic acid (α-AAA) in plasma, serum, dried blood spots (DBS), urine and dried urine spots (DUS). Fifteen patients with molecularly confirmed PDE were detected using liquid chromatography-mass spectrometry (LC-MS/MS) method. Compared to the control groups, the concentrations of a-AASA, P6C and the sum of a-AASA and P6C (AASA-P6C) in all types of samples from PDE patients were markedly elevated. The PA and a-AAA concentrations ranges overlapped partially between PDE patients and control groups. The concentrations of all the analytes in plasma and serum, as well as in urine and DUS were highly correlated. Our study provided more options for the diverse sample collection in the biochemical tests according to practical requirements. With treatment modality of newly triple therapy investigated, biomarker study might play important role not only on diagnosis but also on treatment monitoring and fine tuning the diet. The persistently elevated analytes with good correlation between plasma and DBS, as well as urine and DUS made neonatal screening using DBS and DUS possible.
Assuntos
Ácido 2-Aminoadípico/análogos & derivados , Ácido 2-Aminoadípico/sangue , Epilepsia/sangue , Ácidos Picolínicos/sangue , Ácidos Pipecólicos/sangue , Espectrometria de Massas em Tandem/métodos , Ácido 2-Aminoadípico/metabolismo , Ácido 2-Aminoadípico/urina , Biomarcadores/sangue , Biomarcadores/urina , Criança , Pré-Escolar , Cromatografia Líquida/métodos , Epilepsia/diagnóstico , Epilepsia/urina , Feminino , Humanos , Lactente , Lisina/metabolismo , Masculino , Programas de Rastreamento , Ácidos Picolínicos/metabolismo , Ácidos Picolínicos/urina , Ácidos Pipecólicos/metabolismo , Ácidos Pipecólicos/urinaRESUMO
OBJECTIVE: Fatty acid-binding protein 4 (FABP4) has been proposed to be a potential predictive factor of gestational hypertension or preeclampsia (GH/PE) because of its integrating metabolic and inflammatory responses. Women with gestational diabetes mellitus (GDM) are more likely to develop both GH/PE, than the normal population. The aim of our study was to examine the relationship between plasma FABP4 in the second trimester of pregnancy and the risk of GH/PE in women with GDM. METHODS: This was a nested case-control study conducted within a large on-going prospective cohort study conducted at Peking University First Hospital. A total of 1344 women, who were diagnosed with GDM, according to a 75 g oral glucose tolerance test, participated in the GDM One-Day Clinic at Peking University First Hospital from February 24, 2016 to February 9, 2017. Of the 748 GDM women who agreed to the blood sample collection, 637 were followed until their delivery. The cases included GDM patients who developed gestational hypertension or preeclampsia (GDM-GH/PE group, n = 41). Another 41 matched GDM women without major complications were selected as the control group (GDM group). RESULTS: The incidence of GH/PE was 6.44% and 3.30% for preeclampsia. The level of the second trimester plasma FABP4 in the GDM-GH/PE group was significantly higher than the GDM group (17.53±11.35 vs. 12.79±6.04 ng/ml, P = 0.020). The AUC ROC for the second trimester plasma FABP4 predicted GH/PE in the GDM patients alone was 0.647 (95%CI 0.529-0.766). Multivariate analysis showed that the elevated second trimester FABP4 level was independently associated with GH/PE in the GDM patients (OR 1.136 [95% CI 1.003-1.286], P = 0.045). CONCLUSIONS: Increased second trimester plasma FABP4 independently predicted GH/PE in GDM patients.