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1.
Mol Genet Metab ; 142(2): 108489, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38718669

ABSTRACT

BACKGROUND: Canavan disease is a devastating neurometabolic disorder caused by accumulation of N acetylaspartate in brain and body fluids due to genetic defects in the aspartoacylase gene (ASPA). New gene therapies are on the horizon but will require early presymptomatic diagnosis to be fully effective. METHODS: We therefore developed a fast and highly sensitive liquid chromatography mass spectrometry (LC-MS/MS)-based method for quantification of N-acetylaspartate in dried blood spots and established reference ranges for neonates and older controls. With this test, we investigated 45 samples of 25 Canavan patients including 8 with a neonatal sample. RESULTS: Measuring N-acetylaspartate concentration in dried blood with this novel test, all Canavan patients (with variable severity) were well separated from the control group (median; range: 5.7; 1.6-13.6 µmol/L [n = 45] vs 0.44; 0.24-0.99 µmol/L [n = 59] (p < 0.05)). There was also no overlap when comparing neonatal samples of Canavan patients (7.3; 5.1-9.9 µmol/L [n = 8]) and neonatal controls (0.93; 0.4-1.8 µmol/L [n = 784]) (p < 0.05). CONCLUSIONS: We have developed a new LC-MS/MS-based screening test for early postnatal diagnosis of Canavan disease that should be further evaluated in a population-based study once a promising treatment becomes available. The method meets the general requirements of newborn screening and should be appropriate for multiplexing with other screening approaches that combine chromatographic and mass spectrometry techniques.


Subject(s)
Aspartic Acid , Canavan Disease , Dried Blood Spot Testing , Neonatal Screening , Tandem Mass Spectrometry , Humans , Canavan Disease/diagnosis , Canavan Disease/blood , Canavan Disease/genetics , Infant, Newborn , Neonatal Screening/methods , Dried Blood Spot Testing/methods , Tandem Mass Spectrometry/methods , Aspartic Acid/analogs & derivatives , Aspartic Acid/blood , Chromatography, Liquid , Female , Male , Infant , Child, Preschool , Liquid Chromatography-Mass Spectrometry , Amidohydrolases
2.
Article in English | MEDLINE | ID: mdl-38652590

ABSTRACT

OBJECTIVE: To determine the association of cardiovascular atherosclerotic plaque monosodium urate deposits with the occurrence of major cardiovascular events in gout and hyperuricemia patients. METHODS: This retrospective cohort study included patients with clinically suspicion of gout, who performed a dual energy computed tomography of the affected limb and thorax between June 1st, 2012 and December 5th, 2019. Clinical and laboratory parameters were retrieved from patients charts. Established cardiovascular risk factors were evaluated. Medical history review identified the presence of major adverse cardiac events with a median follow up time of 33 months (range 0-108 months) after the performed computed tomography scan. RESULTS: Full data sets were available for 189 patients: 131 (69.3%) gout patients, 40 (21.2%) hyperuricemia patients, and 18 (9.5%) controls. Patients with cardiovascular monosodium urate deposits (n = 85/189, 45%) revealed increased serum acute phase reactants, uric acid levels and calcium scores in computed tomography compared with patients without cardiovascular monosodium urate deposits. Major adverse cardiac events were observed in 35 patients (18.5%) with a higher prevalence in those patients revealing cardiovascular monosodium urate deposits (n = 22/85, 25.9%) compared with those without cardiovascular monosodium urate deposits (n = 13/104, 12.5%, OR 2.4, p= 0.018). CONCLUSION: This is the first study demonstrating the higher hazard of major adverse cardiac events in patients with dual energy computed tomography-verified cardiovascular monosodium urate deposits. The higher prevalence of cardiac events in patients with cardiovascular monosodium urate deposits may facilitate risk stratification of gout patients, as classical cardiovascular risk scores or laboratory markers fail in their proper identification.

3.
Mov Disord ; 39(3): 510-518, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38140802

ABSTRACT

BACKGROUND: Friedreich's ataxia (FA) is a rare multisystemic disorder which can cause premature death. OBJECTIVES: To investigate predictors of survival in FA. METHODS: Within a prospective registry established by the European Friedreich's Ataxia Consortium for Translational Studies (EFACTS; ClinicalTrials.gov identifier NCT02069509) we enrolled genetically confirmed FA patients at 11 tertiary centers and followed them in yearly intervals. We investigated overall survival applying the Kaplan-Meier method, life tables, and log-rank test. We explored prognostic factors applying Cox proportional hazards regression and subsequently built a risk score which was assessed for discrimination and calibration performance. RESULTS: Between September 2010 and March 2017, we enrolled 631 FA patients. Median age at inclusion was 31 (range, 6-76) years. Until December 2022, 44 patients died and 119 terminated the study for other reasons. The 10-year cumulative survival rate was 87%. In a multivariable analysis, the disability stage (hazard ratio [HR] 1.51, 95% CI 1.08-2.12, P = 0.02), history of arrhythmic disorder (HR 2.93, 95% CI 1.34-6.39, P = 0.007), and diabetes mellitus (HR 2.31, 95% CI 1.05-5.10, P = 0.04) were independent predictors of survival. GAA repeat lengths did not improve the survival model. A risk score built on the previously described factors plus the presence of left ventricular systolic dysfunction at echocardiography enabled identification of four trajectories to prognosticate up to 10-year survival (log-rank test P < 0.001). CONCLUSIONS: Arrhythmias, progressive neurological disability, and diabetes mellitus influence the overall survival in FA. We built a survival prognostic score which identifies patients meriting closer surveillance and who may benefit from early invasive cardiac monitoring and therapy. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Subject(s)
Diabetes Mellitus , Friedreich Ataxia , Humans , Child , Adolescent , Young Adult , Adult , Middle Aged , Aged , Prospective Studies , Registries
4.
J Chem Inf Model ; 64(3): 712-723, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38301279

ABSTRACT

We present a quantum mechanical/machine learning (ML) framework based on random forest to accurately predict the pKas of complex organic molecules using inexpensive density functional theory (DFT) calculations. By including physics-based features from low-level DFT calculations and structural features from our connectivity-based hierarchy (CBH) fragmentation protocol, we can correct the systematic error associated with DFT. The generalizability and performance of our model are evaluated on two benchmark sets (SAMPL6 and Novartis). We believe the carefully curated input of physics-based features lessens the model's data dependence and need for complex deep learning architectures, without compromising the accuracy of the test sets. As a point of novelty, our work extends the applicability of CBH, employing it for the generation of viable molecular descriptors for ML.


Subject(s)
Models, Chemical , Quantum Theory , Thermodynamics , Machine Learning
5.
J Headache Pain ; 25(1): 92, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38834953

ABSTRACT

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a debilitating condition characterized by increased intracranial pressure often presenting with chronic migraine-like headache. Calcitonin gene-related peptide (CGRP) plays an important pathophysiological role in primary headaches such as migraine, whilst its role in IIH has not yet been established. METHODS: This longitudinal exploratory study included patients with IIH, episodic migraine (EM) in a headache-free interval and healthy controls (HC). Blood samples were collected from a cubital vein and plasma CGRP (pCGRP) levels were measured by standardized ELISA. RESULTS: A total of 26 patients with IIH (mean age 33.2 years [SD 9.2], 88.5% female, median BMI 34.8 kg/m2 [IQR 30.0-41.4]), 30 patients with EM (mean age 27.6 years [7.5], 66.7% female) and 57 HC (mean age 25.3 years [5.2], 56.1% female) were included. pCGRP levels displayed a wide variation in IIH as well as in EM and HC on a group-level. Within IIH, those with migraine-like headache had significantly higher pCGRP levels than those with non-migraine-like headache (F(2,524) = 84.79; p < 0.001) and headache absence (F(2,524) = 84.79; p < 0.001) throughout the observation period, explaining 14.7% of the variance in pCGRP levels. CGRP measurements showed strong intraindividual agreement in IIH (ICC 0.993, 95% CI 0.987-0.996, p < 0.001). No association was found between pCGRP levels and ophthalmological parameters. CONCLUSIONS: Although interindividual heterogeneity of pCGRP levels is generally high, migraine-like headache seems to be associated with higher pCGRP levels. CGRP may play a role in the headache pathophysiology at least in a subgroup of IIH.


Subject(s)
Calcitonin Gene-Related Peptide , Migraine Disorders , Pseudotumor Cerebri , Humans , Female , Male , Adult , Calcitonin Gene-Related Peptide/blood , Pseudotumor Cerebri/blood , Migraine Disorders/blood , Longitudinal Studies , Young Adult , Biomarkers/blood
6.
Reprod Biomed Online ; 46(1): 196-202, 2023 01.
Article in English | MEDLINE | ID: mdl-36379855

ABSTRACT

RESEARCH QUESTION: Are outlier high values of first-measured human chorionic gonadotrophin (HCG) following embryo transfer related to pregnancy complications, specifically pre-eclampsia? DESIGN: This retrospective cohort study screened 3448 women aged 18-45 years who underwent IVF between 2014 and 2019 and evaluated 614 women who had an intrauterine pregnancy following single embryo transfer (SET), 423 of whom had a live birth. Pregnancy and birth outcome information was available for final analysis in 280 cases. The setting was a university-based IVF centre. HCG was measured at a standardized time after the embryo transfer and the values correlated with adverse pregnancy outcomes associated with poor placentation. RESULTS: Women with first-measured HCG in the highest quintile had a higher incidence of pre-eclampsia than those with lower HCG concentrations (odds ratio [OR] 4.08, 95% confidence interval [CI] 1.41-11.82) even after controlling for age, body mass index, parity and type of embryo transfer. Additionally controlling for embryo stage at embryo transfer did not change the results (OR 3.97, 95% CI 1.37-11.46). No differences were found in the incidence of fetal growth restriction. CONCLUSIONS: This is the first known report that links high first-measured HCG after SET to an adverse pregnancy outcome. If confirmed by future studies, initiation of preventive interventions at a very early stage of pregnancy merits further evaluation in this cohort of patients.


Subject(s)
Pre-Eclampsia , Pregnancy , Humans , Female , Pre-Eclampsia/epidemiology , Pre-Eclampsia/etiology , Retrospective Studies , Embryo Transfer/adverse effects , Chorionic Gonadotropin , Pregnancy Outcome , Pregnancy Rate , Fertilization in Vitro
7.
J Phys Chem A ; 127(15): 3472-3483, 2023 Apr 20.
Article in English | MEDLINE | ID: mdl-37014825

ABSTRACT

While accurate wave function theories like CCSD(T) are capable of modeling molecular chemical processes, the associated steep computational scaling renders them intractable for treating large systems or extensive databases. In contrast, density functional theory (DFT) is much more computationally feasible yet often fails to quantitatively describe electronic changes in chemical processes. Herein, we report an efficient delta machine learning (ΔML) model that builds on the Connectivity-Based Hierarchy (CBH) scheme─an error correction approach based on systematic molecular fragmentation protocols─and achieves coupled cluster accuracy on vertical ionization potentials by correcting for deficiencies in DFT. The present study integrates concepts from molecular fragmentation, systematic error cancellation, and machine learning. First, we show that by using an electron population difference map, ionization sites within a molecule may be readily identified, and CBH correction schemes for ionization processes may be automated. As a central feature of our work, we employ a graph-based QM/ML model, which embeds atom-centered features describing CBH fragments into a computational graph to further increase accuracy for the prediction of vertical ionization potentials. In addition, we show that the incorporation of electronic descriptors from DFT, namely electron population difference features, improves model performance well beyond chemical accuracy (1 kcal/mol) to approach benchmark accuracy. While the raw DFT results are strongly dependent on the underlying functional used, for our best models, the performance is robust and much less dependent on the functional.

8.
J Nat Prod ; 86(8): 1968-1979, 2023 08 25.
Article in English | MEDLINE | ID: mdl-37531219

ABSTRACT

Six new ravidomycin analogs (1-4, 6, and 7) were isolated from Streptomyces sp. Am59 using UV- and LCMS-guided separation based on Global Natural Products Social (GNPS) molecular networking analysis. Furthermore, we isolated fucomycin V (9), which possesses the same chromophore as ravidomycin but features a d-fucopyranose instead of d-ravidosamine. This is the first report of 9 as a natural product. Four new analogs (10-13) of 9 were also isolated. The structures were elucidated by combined spectroscopic and computational methods. We also found an inconsistency with the published [α]D25 of deacetylravidomycin, which is reported to have a (-) sign. Instead, we observed a (+) specific rotation for the reported absolute configuration of deacetylravidomycin (containing d-ravidosamine). We confirmed the positive sign by reisolating deacetylravidomycin from S. ravidus and by deacetylating ravidomycin. Finally, antibacterial, antifungal, and cytotoxicity activities were determined for the compounds. Compared to deacetylravidomycin, the compounds 4-6, 9, 11, and 12 exhibited greater antibacterial selectivity.


Subject(s)
Antineoplastic Agents , Streptomyces , Streptomyces/chemistry , Aminoglycosides , Anti-Bacterial Agents/chemistry , Molecular Structure
9.
J Allergy Clin Immunol ; 149(1): 388-399.e4, 2022 01.
Article in English | MEDLINE | ID: mdl-34033843

ABSTRACT

BACKGROUND: Rubella virus-induced granulomas have been described in patients with various inborn errors of immunity. Most defects impair T-cell immunity, suggesting a critical role of T cells in rubella elimination. However, the molecular mechanism of virus control remains elusive. OBJECTIVE: This study sought to understand the defective effector mechanism allowing rubella vaccine virus persistence in granulomas. METHODS: Starting from an index case with Griscelli syndrome type 2 and rubella skin granulomas, this study combined an international survey with a literature search to identify patients with cytotoxicity defects and granuloma. The investigators performed rubella virus immunohistochemistry and PCR and T-cell migration assays. RESULTS: This study identified 21 patients with various genetically confirmed cytotoxicity defects, who presented with skin and visceral granulomas. Rubella virus was demonstrated in all 12 accessible biopsies. Granuloma onset was typically before 2 years of age and lesions persisted from months to years. Granulomas were particularly frequent in MUNC13-4 and RAB27A deficiency, where 50% of patients at risk were affected. Although these proteins have also been implicated in lymphocyte migration, 3-dimensional migration assays revealed no evidence of impaired migration of patient T cells. Notably, patients showed no evidence of reduced control of concomitantly given measles, mumps, or varicella live-attenuated vaccine or severe infections with other viruses. CONCLUSIONS: This study identified lymphocyte cytotoxicity as a key effector mechanism for control of rubella vaccine virus, without evidence for its need in control of live measles, mumps, or varicella vaccines. Rubella vaccine-induced granulomas are a novel phenotype with incomplete penetrance of genetic disorders of cytotoxicity.


Subject(s)
Granuloma/etiology , Rubella Vaccine/adverse effects , T-Lymphocytes/immunology , Child , Child, Preschool , Female , Granuloma/genetics , Granuloma/immunology , Granuloma/virology , Humans , Infant , Phenotype , Rubella/genetics , Rubella/immunology , Rubella/virology , Skin/immunology , Skin/virology
10.
Phys Chem Chem Phys ; 24(23): 14525-14537, 2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35661842

ABSTRACT

Methods which accurately predict protein-ligand binding strengths are critical for drug discovery. In the last two decades, advances in chemical modelling have enabled steadily accelerating progress in the discovery and optimization of structure-based drug design. Most computational methods currently used in this context are based on molecular mechanics force fields that often have deficiencies in describing the quantum mechanical (QM) aspects of molecular binding. In this study, we show the competitiveness of our QM-based Molecules-in-Molecules (MIM) fragmentation method for characterizing binding energy trends for seven different datasets of protein-ligand complexes. By using molecular fragmentation, the MIM method allows for accelerated QM calculations. We demonstrate that for classes of structurally similar ligands bound to a common receptor, MIM provides excellent correlation to experiment, surpassing the more popular Molecular Mechanics Poisson-Boltzmann Surface Area (MM/PBSA) and Molecular Mechanics Generalized Born Surface Area (MM/GBSA) methods. The MIM method offers a relatively simple, well-defined protocol by which binding trends can be ascertained at the QM level and is suggested as a promising option for lead optimization in structure-based drug design.


Subject(s)
Molecular Dynamics Simulation , Proteins , Drug Design , Ligands , Protein Binding , Proteins/chemistry , Quantum Theory , Thermodynamics
11.
J Allergy Clin Immunol ; 148(1): 250-255.e1, 2021 07.
Article in English | MEDLINE | ID: mdl-33338535

ABSTRACT

BACKGROUND: Proline-serine-threonine phosphatase-interacting protein 1-associated myeloid-related proteinemia inflammatory (PAMI) syndrome is a novel genetic disorder, causing hypercalprotectinemia and hyperzincemia with inflammatory complications accompanied by cytopenia. Immunosuppressive and/or anticytokine therapy is of limited effect. OBJECTIVES: Because of cytokine production in nonhematopoietic tissues, the potential therapeutic effect of allogeneic hematopoietic stem cell transplantation (HSCT) in autoinflammatory disorders, including PAMI syndrome, has remained uncertain. METHODS: Five patients with PAMI syndrome underwent allogeneic HSCT with myeloablative (4) or reduced-intensity (1) conditioning regimens. Lack of PAMI disease control served as indication for the HSCT in 4 patients and myelodysplastic syndrome development in 1. RESULTS: All 5 patients engrafted; however, 1 patient at day +13 developed hemophagocytic syndrome, followed by graft rejection at day +17. After 5.5 months, a second HSCT was performed from an alternative donor. A further patient at day +116 developed an intense inflammatory syndrome with significant serositis and severe mitral and aortic valve regurgitation, controlled with adalimumab, tacrolimus, and prednisone. No other noninfectious inflammatory episodes, or acute or chronic graft-versus-host disease, occurred in any patient. At the last follow-up (median, 2.2 years), all 5 patients have predominantly or complete donor chimerism and adequate immune recovery and are free of any PAMI symptoms. CONCLUSIONS: Allogeneic HSCT seems to be an effective option to cure cytopenia and severe autoinflammation in PAMI syndrome and may be a curative option for other proline-serine-threonine phosphatase-interacting protein 1-associated inflammatory disorders with poor therapeutic control.


Subject(s)
Adaptor Proteins, Signal Transducing/immunology , Cytoskeletal Proteins/immunology , Genetic Diseases, Inborn/immunology , Graft vs Host Disease/immunology , Inflammation/immunology , Myeloid Cells/immunology , Child, Preschool , Cytokines/immunology , Female , Graft Rejection , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Immunosuppressive Agents/immunology , Infant, Newborn , Male , Transplantation Conditioning/adverse effects , Transplantation, Homologous/adverse effects
12.
Chemistry ; 27(68): 17012-17023, 2021 Dec 06.
Article in English | MEDLINE | ID: mdl-34251056

ABSTRACT

We compare three methods for quantitatively distinguishing the location of noble metal (NM) particles in mesopores from those found on the external support surface. MCM-41 and SBA-15 with NM located in mesopores or on the external surface were prepared and characterized by TEM. 31 P MAS NMR spectroscopy was used to quantify arylphosphines in complexes with NM. Phosphine/NM ratios drop from 2.0 to 0.2 when increasing the probe diameter from 1.08 to 1.54 nm. The reaction between NM and triphenylphosphine (TPP) within 3.0 nm MCM-41 pores takes due to confinement effects multiple weeks. In contrast, external NM react with TPP instantly. A promising method is filling the pores by using the pore volume impregnation technique with tetraethylorthosilicate (TEOS). TPP loading revealed that 66 % of NMs are located on the external surface of MCM-41. The pore filling method can be used in association with any probe molecule, also for the quantification of acid sites.

13.
Eur Surg Res ; 62(2): 97-104, 2021.
Article in English | MEDLINE | ID: mdl-34023826

ABSTRACT

BACKGROUND: Postoperative pancreatic fistula (POPF) is a major complication in pancreatic surgery and can cause considerable postoperative morbidity. Advanced surgical-technical approaches to prevent POPF did not yield a substantial improvement. To investigate innovative treatments, experimental animal models of distal pancreatic resection and pancreaticoduodenectomy are of fundamental importance. After a failed attempt to replicate a previously described rat model for pancreatic fistula induction, we proceeded to distal pancreatic resection with splenectomy to provoke pancreatic leakage and generate a suitable animal model. METHODS: Distal pancreatic resection with splenectomy was performed in 40 rats. The rats were sacrificed on postoperative day (POD) 1, 2, 4, 6, 8, or 10, and the abdominal cavity was explored. Ascites probes were collected pre- and postoperatively for the detection of pancreas amylase and lipase. Tissue samples from the naïve pancreas (POD 0) and the postoperatively harvested remnant were evaluated histologically. The extent of necrosis was determined, and samples were examined for neutrophil infiltration. TUNEL staining served for the verification of necrosis in distinct cases. Immunohistochemistry of Ki67, von Willebrand factor, and CD68 was performed to evaluate proliferation, blood-vessel sprouting, and macrophage invasion. RESULTS: The rats showed no clinical symptoms or severe complications in the postoperative course up to 10 days. Abdominal exploration revealed adhesions in the upper abdomen, but no intra-abdominal fluid accumulations were found. Signs of inflammation and tissue damage were evident at the pancreatic resection margin on histological examination whereas the naïve pancreatic tissue was widely unaffected. Statistically significant differences were seen between the preoperative and postoperative extent of necrosis, the presence of neutrophil infiltrate, and levels of ascitic amylase and lipase. Immunohistochemical staining on Ki67, von Willebrand factor, and CD68 did not reveal any workable results on nonstatistical examination, and it was therefore not considered for further analyses. CONCLUSION: Creating a functional animal model of pancreatic fistula that reflects the clinical and pathophysiological impact of pancreatic leakage in humans has not been achieved. Our approach of left pancreatic resection recapitulated inflammation and tissue damage, early events in the development of fistulas, and it could be suitable for the experimental testing of novel targeting methods.


Subject(s)
Pancreas , Pancreatic Fistula , Pancreatitis , Amylases , Animals , Inflammation , Ki-67 Antigen , Lipase , Necrosis , Pancreas/surgery , Pancreatic Fistula/etiology , Pancreaticoduodenectomy , Postoperative Complications/etiology , Rats , Risk Factors , Splenectomy/adverse effects , von Willebrand Factor
14.
J Clin Immunol ; 40(6): 901-916, 2020 08.
Article in English | MEDLINE | ID: mdl-32638196

ABSTRACT

Isolated neuroinflammatory disease has been described in case reports of familial hemophagocytic lymphohistiocytosis (FHL), but the clinical spectrum of disease manifestations, response to therapy and prognosis remain poorly defined. We combined an international survey with a literature search to identify FHL patients with (i) initial presentation with isolated neurological symptoms; (ii) absence of cytopenia and splenomegaly at presentation; and (iii) systemic HLH features no earlier than 3 months after neurological presentation. Thirty-eight (20 unreported) patients were identified with initial diagnoses including acute demyelinating encephalopathy, leukoencephalopathy, CNS vasculitis, multiple sclerosis, and encephalitis. Median age at presentation was 6.5 years, most commonly with ataxia/gait disturbance (75%) and seizures (53%). Diffuse multifocal white matter changes (79%) and cerebellar involvement (61%) were common MRI findings. CSF cell count and protein were increased in 22/29 and 15/29 patients, respectively. Fourteen patients progressed to systemic inflammatory disease fulfilling HLH-2004 criteria at a mean of 36.9 months after initial neurological presentation. Mutations were detected in PRF1 in 23 patients (61%), RAB27A in 10 (26%), UNC13D in 3 (8%), LYST in 1 (3%), and STXBP2 in 1 (3%) with a mean interval to diagnosis of 28.3 months. Among 19 patients who underwent HSCT, 11 neurologically improved, 4 were stable, one relapsed, and 3 died. Among 14 non-transplanted patients, only 3 improved or had stable disease, one relapsed, and 10 died. Isolated CNS-HLH is a rare and often overlooked cause of inflammatory brain disease. HLH-directed therapy followed by HSCT seems to improve survival and outcome.


Subject(s)
Lymphohistiocytosis, Hemophagocytic/diagnosis , Phenotype , Adolescent , Adult , Age of Onset , Alleles , Biomarkers , Biopsy , Child , Child, Preschool , Disease Progression , Female , Genetic Predisposition to Disease , Genotype , Hematopoietic Stem Cell Transplantation/adverse effects , Hematopoietic Stem Cell Transplantation/methods , Humans , Infant , Lymphohistiocytosis, Hemophagocytic/etiology , Lymphohistiocytosis, Hemophagocytic/metabolism , Magnetic Resonance Imaging , Male , Mutation , Neuroimaging , Symptom Assessment , Young Adult
15.
Phys Chem Chem Phys ; 22(8): 4439-4452, 2020 Feb 26.
Article in English | MEDLINE | ID: mdl-32051989

ABSTRACT

The redox potential is a powerful thermodynamic and kinetic tool used to predict numerous chemical and biochemical mechanisms. However, despite the improving predictive power of density functional theory (DFT), chemically accurate theoretical redox potentials are often difficult to achieve with DFT. For example, calculated redox potentials are sensitive to density functional choice and often fall short of the desired accuracy. Thus, ranges of errors for computed redox potentials between different density functionals can become quite large. The current study presents a cost-effective protocol that utilizes effective error cancellation schemes in order to accurately predict the redox potentials of a wide range of organic molecules. This computational protocol, called CBH-Redox, is an extension of the connectivity-based hierarchy (CBH) method, and produces thermochemical data with near-G4 accuracy. Herein, we test the CBH-Redox protocol against both experimental and G4 reference values and compare these results to DFT alone. Considering 46 C, O, N, F, Cl, and S atom-containing molecules, when using the CBH-Redox correction scheme, the MAEs for all eight density functionals tested are within the 0.09 V target accuracy versus both experiment and G4. Moreover, CBH-Redox achieves an impressive accuracy, with a MAE of 0.05 V or below when compared to G4 for six of the eight density functionals tested. In addition, when the CBH correction is applied, the error range across all functionals tested decreases from 0.12 V to about 0.05 V versus G4, and from 0.13 V to 0.04 V versus experiment.

17.
Chembiochem ; 16(8): 1175-82, 2015 May 26.
Article in English | MEDLINE | ID: mdl-25907804

ABSTRACT

The biologically active compound mensacarcin is produced by Streptomyces bottropensis. The cosmid cos2 contains a large part of the mensacarcin biosynthesis gene cluster. Heterologous expression of this cosmid in Streptomyces albus J1074 led to the production of the intermediate didesmethylmensacarcin (DDMM). In order to gain more insights into the biosynthesis, gene inactivation experiments were carried out by λ-Red/ET-mediated recombination, and the deletion mutants were introduced into the host S. albus. In total, 23 genes were inactivated. Analysis of the metabolic profiles of the mutant strains showed the complete collapse of DDMM biosynthesis, but upon overexpression of the SARP regulatory gene msnR1 in each mutant new intermediates were detected. The compounds were isolated, and their structures were elucidated. Based on the results the specific functions of several enzymes were determined, and a pathway for mensacarcin biosynthesis is proposed.


Subject(s)
Anthracenes/metabolism , Luciferases/genetics , Mixed Function Oxygenases/genetics , Multigene Family/genetics , Open Reading Frames/genetics , Biocatalysis , Gene Deletion , Mixed Function Oxygenases/deficiency , Mixed Function Oxygenases/isolation & purification , Mixed Function Oxygenases/metabolism , Streptomyces/enzymology , Streptomyces/genetics , Streptomyces/metabolism
18.
Chembiochem ; 15(5): 749-56, 2014 Mar 21.
Article in English | MEDLINE | ID: mdl-24554499

ABSTRACT

Mensacarcin, a potential antitumour drug, is produced by Streptomyces bottropensis. The structure consists of a three-membered ring system with many oxygen atoms. Of vital importance in this context is an epoxy moiety in the side chain of mensacarcin. Our studies with different mensacarcin derivatives have demonstrated that this epoxy group is primarily responsible for the cytotoxic effect of mensacarcin. In order to obtain further information about this epoxy moiety, inactivation experiments in the gene cluster were carried out to identify the epoxy-forming enzyme. Therefore the cosmid cos2, which covers almost the complete type II polyketide synthase (PKS) gene cluster, was heterologously expressed in Streptomyces albus. This led to production of didesmethylmensacarcin, due to the fact that methyltransferase genes are missing in the cosmid. Further gene inactivation experiments on this cosmid showed that MsnO8, a luciferase-like monooxygenase, introduces the epoxy group at the end of the biosynthesis of mensacarcin. In addition, the protein MsnO8 was purified, and its crystal structure was determined to a resolution of 1.80 Å.


Subject(s)
Anthracenes/metabolism , Antineoplastic Agents/metabolism , Epoxy Compounds/metabolism , Oxygenases/metabolism , Streptomyces/enzymology , Amino Acid Sequence , Anthracenes/chemistry , Cloning, Molecular , Crystallography, X-Ray , Epoxy Compounds/chemistry , Models, Molecular , Molecular Sequence Data , Multigene Family , Oxygenases/chemistry , Oxygenases/genetics , Polyketide Synthases/genetics , Polyketide Synthases/metabolism , Streptomyces/chemistry , Streptomyces/genetics , Streptomyces/metabolism
19.
J Chem Theory Comput ; 20(7): 2774-2785, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38530869

ABSTRACT

The complexity and size of large molecular systems, such as protein-ligand complexes, pose computational challenges for accurate post-Hartree-Fock calculations. This study delivers a thorough benchmarking of the Molecules-in-Molecules (MIM) method, presenting a clear and accessible strategy for layer/theory selections in post-Hartree-Fock computations on substantial molecular systems, notably protein-ligand complexes. An approach is articulated, enabling augmented computational efficiency by strategically canceling out common subsystem energy terms between complexes and proteins within the supermolecular equation. Employing DLPNO-based post-Hartree-Fock methods in conjunction with the three-layer MIM method (MIM3), this study demonstrates the achievement of protein-ligand binding energies with remarkable accuracy (errors <1 kcal mol-1), while significantly reducing computational costs. Furthermore, noteworthy correlations between theoretically computed interaction energies and their experimental equivalents were observed, with R2 values of approximately 0.90 and 0.78 for CDK2 and BZT-ITK sets, respectively, thus validating the efficacy of the MIM method in calculating binding energies. By highlighting the crucial role of diffuse or small Pople-style basis sets in the middle layer for reducing energy errors, this work provides valuable insights and practical methodologies for interaction energy computations in large molecular complexes and opens avenues for their application across a diverse range of molecular systems.


Subject(s)
Proteins , Quantum Theory , Ligands , Thermodynamics , Proteins/chemistry , Protein Binding
20.
Fertil Steril ; 121(5): 824-831, 2024 May.
Article in English | MEDLINE | ID: mdl-38211763

ABSTRACT

OBJECTIVE: To compare the success rates of medical management using a combined mifepristone and misoprostol protocol in cases of early pregnancy loss (EPL) between women who conceived without medical assistance and those who conceived through in vitro fertilization (IVF), after fresh or frozen embryo transfer, and evaluate for the predictive factors of success, time to first passage of tissue, and time to complete resolution of pregnancy. DESIGN: Retrospective cohort study. SETTING: University hospital. PATIENT(S): Women who presented with EPL below 13 weeks of gestation between June 2013 and July 2021 who were managed medically with mifepristone 200 mg orally and misoprostol 800 mcg vaginally were included in the study. INTERVENTION(S): Medical management with mifepristone and misoprostol; conception without medical assistance vs. post-IVF, after fresh or frozen embryo transfer. MAIN OUTCOME MEASURE(S): We evaluated overall success and performed subgroup analysis according to the mode of conception and compared fresh vs. frozen-thawed embryo transfers for IVF pregnancies. In all groups, we also calculated success according to gestational age and compared the time to first passage of tissue. The potential predictive factors of treatment success were analyzed. The side effects and complications of treatment were recorded. RESULT(S): A total of 930 women were included in the study, 99 (11%) of whom achieved pregnancy after IVF. The overall success of medical treatment was 89% with no statistically significant difference according to the mode of conception (89% vs. 89%) or type of transfer (fresh 89% vs. frozen 89%). Only lower gestational age by sonography was independently predictive of treatment success, showing a negative regression coefficient of ß = -0.333 and an odds ratio of 0.717. The mean time to first passage of tissue was 5.0 ± 2.1 hours. Altogether, 666 women (72%) showed pregnancy resolution on the day of medication administration, an additional 110 women at 1-week follow-up, and a further 74 women after ≥4 weeks on ultrasound. CONCLUSION(S): Medical management of EPL with mifepristone and misoprostol is a highly successful treatment option that results in completed abortion in a timely fashion in both pregnancies conceived without medical assistance and those conceived after IVF.


Subject(s)
Abortion, Spontaneous , Embryo Transfer , Fertilization in Vitro , Mifepristone , Misoprostol , Humans , Female , Pregnancy , Retrospective Studies , Adult , Mifepristone/administration & dosage , Mifepristone/adverse effects , Mifepristone/therapeutic use , Fertilization in Vitro/methods , Misoprostol/administration & dosage , Misoprostol/adverse effects , Abortion, Spontaneous/epidemiology , Abortion, Spontaneous/etiology , Embryo Transfer/methods , Treatment Outcome , Abortifacient Agents, Nonsteroidal/administration & dosage , Abortifacient Agents, Nonsteroidal/adverse effects , Abortifacient Agents, Steroidal/administration & dosage , Abortifacient Agents, Steroidal/adverse effects , Administration, Oral
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