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1.
Int J Mol Sci ; 24(7)2023 Apr 06.
Article in English | MEDLINE | ID: mdl-37047841

ABSTRACT

Studies have been actively conducted to ensure that gadolinium-based contrast agents for magnetic resonance imaging (MRI) are accompanied by various biological functions. A new example is the anti-inflammatory theragnostic MRI agent to target inflammatory mediators for imaging diagnosis and to treat inflammatory diseases simultaneously. We designed, synthesized, and characterized a Gd complex of 1,4,7-tris(carboxymethylaza) cyclododecane-10-azaacetylamide (DO3A) conjugated with a nonsteroidal anti-inflammatory drug (NSAID) that exerts the innate therapeutic effect of NSAIDs and is also applicable in MRI diagnostics. Gd-DO3A-fen (0.1 mmol/kg) was intravenously injected into the turpentine oil-induced mouse model, with Gd-DO3A-BT as a control group. In the in vivo MRI experiment, the contrast-to-noise ratio (CNR) was higher and persisted longer than that with Gd-DO3A-BT; specifically, the CNR difference was almost five times at 2 h after injection. Gd-DO3A-fen had a binding affinity (Ka) of 6.68 × 106 M-1 for the COX-2 enzyme, which was 2.1-fold higher than that of fenbufen, the original NSAID. In vivo evaluation of anti-inflammatory activity was performed in two animal models. In the turpentine oil-induced model, the mRNA expression levels of inflammatory parameters such as COX-2, TNF-α, IL-1ß, and IL-6 were reduced, and in the carrageenan-induced edema model, swelling was suppressed by 72% and there was a 2.88-fold inhibition compared with the saline group. Correlation analysis between in vitro, in silico, and in vivo studies revealed that Gd-DO3A-fen acts as an anti-inflammatory theragnostic agent by directly binding to COX-2.


Subject(s)
Organometallic Compounds , Animals , Mice , Organometallic Compounds/chemistry , Gadolinium/chemistry , Cyclooxygenase 2/genetics , Turpentine , Contrast Media/chemistry , Magnetic Resonance Imaging/methods , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/pharmacology
2.
J Enzyme Inhib Med Chem ; 37(1): 1257-1277, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35484863

ABSTRACT

Identification of highly selective type II kinase inhibitors is described. Two different chiral peptidomimetic scaffolds were introduced on the tail region of non-selective type II kinase inhibitor GNF-7 to enhance the selectivity. Kinome-wide selectivity profiling analysis showed that type II kinase inhibitor 7a potently inhibited Lck kinase with great selectivity (IC50 of 23.0 nM). It was found that 7a and its derivatives possessed high selectivity for Lck over even structurally conserved all Src family kinases. We also observed that 7a inhibited Lck activation in Jurkat T cells. Moreover, 7a was found to alleviate clinical symptoms in DSS-induced colitis mice. This study provides a novel insight into the design of selective type II kinase inhibitors by adopting chiral peptidomimetic moieties on the tail region.


Subject(s)
Peptidomimetics , Animals , Lymphocyte Specific Protein Tyrosine Kinase p56(lck) , Mice , Peptidomimetics/pharmacology , Protein Kinase Inhibitors/pharmacology , src-Family Kinases
3.
J Chem Inf Model ; 61(1): 36-45, 2021 01 25.
Article in English | MEDLINE | ID: mdl-33252229

ABSTRACT

Following identification of a target protein, hit identification, which finds small organic molecules that bind to the target, is an important first step of a structure-based drug design project. In this study, we demonstrate a target-specific drug design method that can autonomously generate a series of target-favorable compounds. This method utilizes the seq2seq model based on a deep learning algorithm and a water pharmacophore. Water pharmacophore models are used to screen compounds that are favorable to a given target in a large compound database, and seq2seq compound generators are used to train the screened compounds and generate entirely new compounds based on the training model. Our method was tested through binding energy calculation studies of six pharmaceutically relevant targets in the directory of useful decoys (DUD) set with docking. The compounds generated by our method had lower average binding energies than decoy compounds in five out of six cases and included a number of compounds that had lower binding energies than the average binding energies of the active compounds in four cases. The generated compound lists for these four cases featured compounds with lower binding energies than even the most active compounds.


Subject(s)
Deep Learning , Drug Design , Algorithms , Ligands , Molecular Docking Simulation , Proteins , Water
4.
Medicina (Kaunas) ; 57(9)2021 Sep 04.
Article in English | MEDLINE | ID: mdl-34577854

ABSTRACT

Backgroundand Objectives: Aspirin is used globally to reduce pain and inflammation; however, its effect in patients with coronavirus disease (COVID-19) is not fully investigated and remains controversial. We evaluated the association between aspirin and COVID-19 outcomes using nationwide data from the Korean National Health Insurance System. Materials and Methods: This was a retrospective observational cohort study that included 22,660 eligible patients who underwent COVID-19 testing in South Korea between 1 January-31 July 2020. We identified all aspirin users prescribed aspirin within two weeks before or after the index date. The primary outcome was positivity for the COVID-19 test, and secondary outcomes included conventional oxygen therapy, intensive care unit, mechanical ventilation, or death. We applied the propensity score matching method to reduce the possible bias originating from the differences in patients' baseline characteristics. Results: Of those eligible, 662 patients were prescribed aspirin. Among them, 136 patients were on aspirin within two weeks before diagnosis and 526 patients were on aspirin after diagnosis. The COVID-19 test positivity rate was not significantly different according to aspirin use. Aspirin use before COVID-19 was related to an increased death rate and aspirin use after COVID-19 was related to a higher risk of the conventional oxygen therapy. Conclusion: Aspirin use was associated with adverse effects in COVID-19 patients. Further studies for mechanisms are needed.


Subject(s)
Aspirin , COVID-19 , Aspirin/adverse effects , COVID-19 Testing , Cohort Studies , Humans , SARS-CoV-2
5.
Bioconjug Chem ; 29(11): 3614-3625, 2018 11 21.
Article in English | MEDLINE | ID: mdl-30383368

ABSTRACT

In this study, we designed and synthesized a highly stable manganese (Mn2+)-based hepatobiliary complex by tethering an ethoxybenzyl (EOB) moiety with an ethylenediaminetetraacetic acid (EDTA) coordination cage as an alternative to the well-established hepatobiliary gadolinium (Gd3+) chelates and evaluated its usage as a T1 hepatobiliary magnetic resonance imaging (MRI) contrast agent (CA). This new complex exhibits higher r1 relaxivity (2.3 mM-1 s-1) than clinically approved Mn2+-based hepatobiliary complex Mn-DPDP (1.6 mM-1 s-1) at 1.5 T. Mn-EDTA-EOB shows much higher kinetic inertness than that of clinically approved Gd3+-based hepatobiliary MRI CAs, such as Gd-DTPA-EOB and Gd-BOPTA. In addition, in vivo biodistribution and MRI enhancement patterns of this new Mn2+ chelate are comparable to those of Gd3+-based hepatobiliary MRI CAs. The diagnostic efficacy of the new complex was demonstrated by its enhanced tumor detection sensitivity in a liver cancer model using in vivo MRI.


Subject(s)
Biliary Tract/diagnostic imaging , Contrast Media/chemical synthesis , Edetic Acid/chemistry , Liver/diagnostic imaging , Magnetic Resonance Imaging/methods , Manganese/chemistry , Animals , Cell Line , Chelating Agents/chemistry , Chelating Agents/pharmacokinetics , Contrast Media/chemistry , Edetic Acid/pharmacokinetics , Female , Gadolinium DTPA/chemistry , Heterografts , Humans , Hydrogen-Ion Concentration , Kinetics , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/pathology , Male , Mice , Molecular Docking Simulation , Proton Magnetic Resonance Spectroscopy , Spectrometry, Mass, Electrospray Ionization , Spectrometry, Mass, Fast Atom Bombardment
6.
Phys Chem Chem Phys ; 19(37): 25277-25288, 2017 Sep 27.
Article in English | MEDLINE | ID: mdl-28759059

ABSTRACT

Cold atmospheric plasma and gamma rays are known to have anticancer properties, even though their specific mechanisms and roles as co-solvents during their action are still not clearly understood. Despite the use of gamma rays in cancer therapy, they have oncogenic potential, whereas this has not been observed for plasma treatment (to date). To gain a better understanding, we studied the action of dielectric barrier discharge (DBD) plasma and gamma rays on the myoglobin protein. We analyzed the secondary structure and thermodynamic properties of myoglobin after both treatments. In addition, in the last few years, ammonium ionic liquids (ILs) have revealed their important role in protein folding as co-solvents. In this work, we treated the protein with ammonium ILs such as triethylammonium methanesulfonate (TEMS) and tetrabutylammonium methanesulfonate (TBMS) and later treated this IL-protein solution with DBD plasma and gamma rays. In this study, we show the chemical and thermal denaturation of the protein after plasma and gamma treatments in the presence and absence of ILs using circular dichroism (CD) and UV-vis spectroscopy. Furthermore, we also show the influence of plasma and gamma rays on the secondary structure of myoglobin in the absence and presence of ILs or ILs + urea using CD. Finally, molecular dynamic simulations were conducted to gain deeper insight into how the ILs behave to protect the protein against the hydrogen peroxide generated by the DBD plasma and gamma rays.


Subject(s)
Gamma Rays , Ionic Liquids/chemistry , Myoglobin/chemistry , Protein Structure, Secondary , Thermodynamics , Ammonium Compounds , Circular Dichroism , Cold Temperature , Ions , Molecular Dynamics Simulation , Plasma Gases , Protein Folding
7.
Biochim Biophys Acta ; 1848(6): 1294-302, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25753114

ABSTRACT

The melanocortin receptors (MCRs) are members of the G protein-coupled receptor (GPCR) 1 superfamily with seven transmembrane (TM) domains. Among them, the melanocortin-4 receptor (MC4R) subtype has been highlighted recently by genetic studies in obese humans. In particular, in a patient with severe early-onset obesity, a novel heterozygous mutation in the MC4R gene was found in an exchange of Asp to Asn in the 90th amino acid residue located in the TM 2 domain (MC4RD90N). Mutations in the MC4R gene are the most frequent monogenic causes of severe obesity and are described as heterozygous with loss of function. We determine solution structures of the TM 2 domain of MC4R (MC4RTM2) and compared secondary structure of Asp90 mutant (MC4RTM2-D90N) in a micelle environment by nuclear magnetic resonance (NMR) spectroscopy. NMR structure shows that MC4RTM2 forms a long α-helix with a kink at Gly98. Interestingly, the structure of MC4RTM2-D90N is similar to that of MC4RTM2 based on data from CD and NMR spectrum. However, the thermal stability and homogeneity of MC4RD90N is quite different from those of MC4R. The structure from molecular modeling suggests that Asp90(2.50) plays a key role in allosteric sodium ion binding. Our data suggest that the sodium ion interaction of Asp90(2.50) in the allosteric pocket of MC4R is essential to its function, explaining the loss of function of the MC4RD90N mutant.


Subject(s)
Mutant Proteins/chemistry , Mutant Proteins/metabolism , Receptor, Melanocortin, Type 4/chemistry , Receptor, Melanocortin, Type 4/metabolism , Sodium Dodecyl Sulfate/chemistry , Amino Acid Sequence , Binding Sites , Circular Dichroism , Humans , Ions , Magnetic Resonance Spectroscopy , Micelles , Models, Molecular , Molecular Sequence Data , Protein Stability , Protein Structure, Secondary , Receptor, Melanocortin, Type 4/isolation & purification , Salts/pharmacology , Sodium/metabolism , Solutions , Structural Homology, Protein
8.
Phys Chem Chem Phys ; 18(40): 28281-28289, 2016 Oct 12.
Article in English | MEDLINE | ID: mdl-27711562

ABSTRACT

A great number of GPCR crystal structures have been solved in recent years, enabling GPCR-targeted drug discovery using structure-based approaches such as docking. GPCRs generally have wide and open entrances to the binding sites, which render the binding sites readily accessible to solvent. GPCRs are also populated with hydrophilic residues in the extracellular regions. Thus, including solvent and polarization effects can be important for accurate GPCR docking. To test this hypothesis, a new docking protocol which incorporates quantum mechanical/molecular mechanical (QM/MM) calculations along with an implicit solvent model is developed. The new docking method treats the ligands and the protein residues in the binding sites as QM regions and performs QM/MM calculations with implicit solvent. The results of a test on all solved GPCR cocrystals show a significant improvement over the conventional docking method.

9.
Angew Chem Int Ed Engl ; 55(11): 3642-6, 2016 Mar 07.
Article in English | MEDLINE | ID: mdl-26879524

ABSTRACT

Developing selective strategies to treat metastatic cancers remains a significant challenge. Herein, we report the first antibody-recruiting small molecule (ARM) that is capable of recognizing the urokinase-type plasminogen activator receptor (uPAR), a uniquely overexpressed cancer cell-surface marker, and facilitating the immune-mediated destruction of cancer cells. A co-crystal structure of the ARM-U2/uPAR complex was obtained, representing the first crystal structure of uPAR complexed with a non-peptide ligand. Finally, we demonstrated that ARM-U2 substantially suppresses tumor growth in vivo with no evidence of weight loss, unlike the standard-of-care agent doxorubicin. This work underscores the promise of antibody-recruiting molecules as immunotherapeutics for treating cancer.


Subject(s)
Antibodies/immunology , Neoplasm Metastasis/immunology , Urokinase-Type Plasminogen Activator/metabolism , Crystallography, X-Ray , Humans , Neoplasms/pathology
10.
Antioxidants (Basel) ; 13(2)2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38397802

ABSTRACT

Studies in the field have actively pursued the incorporation of diverse biological functionalities into gadolinium-based contrast agents, aiming at the amalgamation of MRI imaging and therapeutic capabilities. In this research, we present the development of Gd-Ga, an anti-neuroinflammatory MR contrast agent strategically designed to target inflammatory mediators for comprehensive imaging diagnosis and targeted lesion treatment. Gd-Ga is a gadolinium complex composed of 1,4,7-tris(carboxymethylaza)cyclododecane-10-azaacetylamide (DO3A) conjugated with gallic acid (3,4,5-trihydroxybenzoic acid). Upon intravenous administration in LPS-induced mouse models, Gd-Ga demonstrated a remarkable three-fold increase in signal-to-noise (SNR) variation compared to Gd-DOTA, particularly evident in both the cortex and hippocampus 30 min post-MR monitoring. In-depth investigations, both in vitro and in vivo, into the anti-neuroinflammatory properties of Gd-Ga revealed significantly reduced protein expression levels of pro-inflammatory mediators compared to the LPS group. The alignment between in silico predictions and phantom studies indicates that Gd-Ga acts as an anti-neuroinflammatory agent by directly binding to MD2. Additionally, the robust antioxidant activity of Gd-Ga was confirmed by its effective scavenging of NO and ROS. Our collective findings emphasize the immense potential of this theranostic complex, where a polyphenol serves as an anti-inflammatory drug, presenting an exceptionally efficient platform for the diagnosis and treatment of neuroinflammation.

11.
J Chem Inf Model ; 52(12): 3278-83, 2012 Dec 21.
Article in English | MEDLINE | ID: mdl-23194275

ABSTRACT

We used molecular dynamics (MD) simulations and protein docking to elucidate the mechanism of allosteric inhibition of the human form of peroxiredoxin (Prx), 2-Cys proliferation associated gene (PAG). Beginning by using the rat form of Prx, 2-Cys heme-binding protein as a template, we used homology modeling to find the structure of human 2-Cys PAG, which is in dimeric form. Molecular dynamics simulations showed that the structure of the reduced form of the 2-Cys PAG dimer fluctuates as the two monomers drift away and approach each other. We then used SiteMap to search for binding sites on the surface of this dimer. A binding site between the two monomers was found, and virtual screening with docking was performed to identify a ligand binding to this site. Subsequent MD simulation revealed that with this ligand in the binding site, the dimer structure of 2-Cys PAG becomes stabilized such that two cysteine residues from two monomers, which are partners of a disulfide bond of the oxidized form, remain separated. This mechanism can be used as an allosteric inhibition of Prx as a hydrogen peroxide reducer, the role of which has been studied as an anticancer drug target.


Subject(s)
Enzyme Inhibitors/metabolism , Enzyme Inhibitors/pharmacology , Molecular Docking Simulation , Molecular Dynamics Simulation , Peroxiredoxins/antagonists & inhibitors , Peroxiredoxins/chemistry , Allosteric Regulation/drug effects , Amino Acid Sequence , Animals , Binding Sites , Drug Discovery , Humans , Molecular Sequence Data , Peroxiredoxins/metabolism , Protein Conformation , Rats , Thermodynamics
12.
Cancers (Basel) ; 14(8)2022 Apr 14.
Article in English | MEDLINE | ID: mdl-35454900

ABSTRACT

Hepatocellular carcinomas (HCCs) are aggressive tumors with a poor prognosis. Approved first-line treatments include sorafenib, lenvatinib, and a combination of atezolizumab and bevacizumab; however, they do not cure HCC. We investigated MBP-11901 as a drug candidate for HCC. Cell proliferation and cytotoxicity were evaluated using normal and cancer human liver cell lines, while Western blotting and flow cytometry evaluated apoptosis. The anticancer effect of MBP-11901 was verified in vitro through migration, invasion, colony formation, and JC-1 MMP assays. In mouse models, the tumor volume, tumor weight, and bodyweight were measured, and cancer cell proliferation and apoptosis were analyzed. The toxicity of MBP-11901 was investigated through GOT/GPT and histological analyses in the liver and kidney. The signaling mechanism of MBP-11901 was investigated through kinase assays, phosphorylation analysis, and in silico docking simulations. Results. MBP-11901 was effective against various human HCC cell lines, leading to the disappearance of most tumors when administered orally in animal models. This effect was dose-dependent, with no differences in efficacy according to administration intervals. MBP-11901 induced anticancer effects by targeting the signaling mechanisms of FLT3, VEGFR2, c-KIT, and PDGFRß. MBP-11901 is suggested as a novel therapeutic agent for the treatment of advanced or unresectable liver cancer.

13.
Pharmaceuticals (Basel) ; 15(6)2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35745670

ABSTRACT

Here, we describe the synthesis, characterization, and in vitro biological evaluation of a series of transition metal complexes containing benzothiazole aniline (BTA). We employed BTA, which is known for its selective anticancer activity, and a salen-type Schiff-based ligand to coordinate several transition metals to achieve selective and synergistic cytotoxicity. The compounds obtained were characterized by NMR spectroscopy, mass spectrometry, Fourier transform infrared spectroscopy, and elemental analysis. The compounds L, MnL, FeL, CoL, and ZnL showed promising in vitro cytotoxicity against cancer cells, and they had a lower IC50 than that of the clinically used cisplatin. In particular, MnL had synergistic cytotoxicity against liver, breast, and colon cancer cells. Moreover, MnL, CoL, and CuL promoted the production of reactive oxygen species in HepG2 tumor cell lines. The lead compound of this series, MnL, remained stable in physiological settings, and docking results showed that it interacted rationally with the minor groove of DNA. Therefore, MnL may serve as a viable alternative to platinum-based chemotherapy.

14.
J Med Chem ; 65(8): 6313-6324, 2022 04 28.
Article in English | MEDLINE | ID: mdl-35418226

ABSTRACT

The purpose of this study is to assess the physicochemical properties and MRI diagnostic efficacy of two newly synthesized 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-type Gd chelates, Gd-SucL and Gd-GluL, with an asymmetric α-substituted pendant arm as potential hepatocyte-specific magnetic resonance imaging contrast agents (MRI CAs). Our findings show that fine conformational changes in the chelating arm affect the in vivo pharmacokinetic behavior of the MRI CA, and that a six-membered chelating substituent of Gd-SucL is more advantageous in this system to avoid unwanted interactions with endogenous species. Gd-SucL exhibited a general DOTA-like chelate stability trend, indicating that all chelating arms retain coordination bonding. Finally, the in vivo diagnostic efficacy of highly stable Gd-SucL as a potential hepatocyte-specific MRI CA was evaluated using T1-weighted MR imaging on an orthotopic hepatocarcinoma model.


Subject(s)
Contrast Media , Gadolinium , Anions , Chelating Agents/chemistry , Contrast Media/chemistry , Gadolinium/chemistry , Liver/diagnostic imaging , Magnetic Resonance Imaging/methods
15.
Cancer Res Treat ; 54(3): 937-949, 2022 Jul.
Article in English | MEDLINE | ID: mdl-34607396

ABSTRACT

PURPOSE: Melanoma incidence is rising worldwide along with the associated personal and socioeconomic health expenditures. We investigated the incidence and survival-rate patterns of melanoma in South Korea using nationwide data. MATERIALS AND METHODS: This retrospective cohort study included patients with melanoma between 2004 and 2017, based on National Health Insurance (NHI) claims data in South Korea. The incidence, prevalence, and survival rate were analyzed along with baseline demographic characteristics. We collected solar irradiation dose (SID) and healthcare ranking score (HRS) according to the administrative district from the Korea Meteorological Administration and Korea Health Promotion Institute. The incidence and survival rates were assessed using Pearson's correlation, the Kaplan-Meier estimation, multiple linear regression, and multiple logistic regression methods. RESULTS: Twenty-five thousand, five hundred ninety-one patients with melanoma were diagnosed during the study period. The age-standardized incidence of melanoma steadily increased from 2004 to 2017 from 2.6 to 3.0/100,000/yr. The incidence of melanoma increased with significantly higher income (p < 0.05). The prevalence followed a similar pattern as the incidence. According to multivariate analysis, HRS significantly influenced the incidence of melanoma in high sun-exposed sites (p < 0.001). There was no significant change in annual mortality. Women had a higher 5-year survival rate than men (78.4% vs. 72.8%). Mortality by the administrative district was highly correlated with HRS. CONCLUSION: The incidence of melanoma is increasing in South Korea. A low HRS is associated with both higher incidence and mortality. The findings of this study could be utilized as a guideline for treating melanoma patients.


Subject(s)
Melanoma , Skin Neoplasms , Female , Humans , Incidence , Insurance, Health , Male , Melanoma/epidemiology , Republic of Korea/epidemiology , Retrospective Studies , Skin Neoplasms/epidemiology , Survival Rate , Melanoma, Cutaneous Malignant
16.
Pharmaceuticals (Basel) ; 14(8)2021 Aug 23.
Article in English | MEDLINE | ID: mdl-34451928

ABSTRACT

We describe the synthesis, characterization, molecular modeling, and in vitro anticancer activity of three benzothiazole aniline (BTA) ligands and their corresponding platinum (II) complexes. We designed the compounds based on the selective antitumor properties of BTA, along with three types of metallic centers, aiming to take advantage of the distinctive and synergistic activity of the complexes to develop anticancer agents. The compounds were characterized using nuclear magnetic resonance spectrometry, Fourier transform infrared spectroscopy, mass spectrometry, elemental analysis, and tested for antiproliferative activity against multiple normal and cancerous cell lines. L1, L2, and L1Pt had better cytotoxicity in the liver, breast, lung, prostate, kidney, and brain cells than clinically used cisplatin. Especially, L1 and L1Pt demonstrated selective inhibitory activities against liver cancer cells. Therefore, these compounds can be a promising alternative to the present chemotherapy drugs.

17.
Neurology ; 2021 May 24.
Article in English | MEDLINE | ID: mdl-34031201

ABSTRACT

ObjectiveTo test the genetic contribution of rare missense variants in COL4A1 and COL4A2 in which common variants are genetically associated with sporadic intracerebral hemorrhage (ICH), we performed rare variant analysis in multiple sequencing data for the risk for sporadic ICH.MethodsWe performed sequencing across 559Kbp at 13q34 including COL4A1 and COL4A2 among 2,133 individuals (1,055 ICH cases; 1,078 controls) in US-based and 1,492 individuals (192 ICH cases; 1,189 controls) from Scotland-based cohorts, followed by sequence annotation, functional impact prediction, genetic association testing, and in silico thermodynamic modeling.ResultsWe identified 107 rare nonsynonymous variants in sporadic ICH, of which two missense variants, rs138269346 (COL4A1I110T) and rs201716258 (COL4A2H203L), were predicted to be highly functional and occurred in multiple ICH cases but not in controls from the US-based cohort. The minor allele of rs201716258 was also present in Scottish ICH patients, and rs138269346 was observed in two ICH-free controls with a history of hypertension and myocardial infarction. Rs138269346 was nominally associated with non-lobar ICH risk (P=0.05), but not with lobar ICH (P=0.08), while associations between rs201716258 and ICH subtypes were non-significant (P>0.12). Both variants were considered pathogenic based on minor allele frequency (<0.00035 in EUR), predicted functional impact (deleterious or probably damaging), and in silico modeling studies (substantially altered physical length and thermal stability of collagen).ConclusionsWe identified rare missense variants in COL4A1/A2 in association with sporadic ICH. Our annotation and simulation studies suggest that these variants are highly functional and may represent targets for translational follow-up.

18.
Int J Biol Macromol ; 155: 439-446, 2020 Jul 15.
Article in English | MEDLINE | ID: mdl-32220643

ABSTRACT

Ionic liquids (ILs) are known to provide stability to biomolecules. ILs are also widely used in the fields of chemical engineering, biological engineering, chemistry, and biochemistry because they facilitate enzyme catalyzed reactions and enhance their conversion rate. In this work, we have evaluated the influence of alkyl chain substitution of ammonium ILs such as diethylammonium dihydrogen phosphate (DEAP) and triethylammonium hydrogen phosphate (TEAP) for the stability and activity of the tobacco etch virus (TEV) protease. Further, we performed molecular dynamics (MD) simulations to calculate the RMSD (root mean square deviation) for TEV and TEV + ILs. Experimental and simulations results show that TEV is more stable in the presence of TEAP than DEAP. Whereas, TEV protease activity for the cleavage of fusion proteins is preserved in the presence of DEAP while lost in the presence of TEAP. Hence, DEAP IL can serve as alternative solvents for the stability of the TEV protease with preserved activity. To the best of our knowledge, this is first study to show that ILs can stabilize and maintain the TEV protease cleavage activity.


Subject(s)
Ammonium Compounds/chemistry , Endopeptidases/chemistry , Endopeptidases/metabolism , Ionic Liquids/chemistry , Enzyme Stability , Models, Molecular , Molecular Dynamics Simulation , Protein Conformation , Solvents/chemistry
19.
ACS Med Chem Lett ; 11(8): 1529-1534, 2020 Aug 13.
Article in English | MEDLINE | ID: mdl-32832019

ABSTRACT

G protein-coupled receptors (GPCRs) have always been important drug targets in the pharmaceutical industry. One major question for the current GPCR drug discovery is how drugs have distinct efficacies at the same GPCR target. Related to this question, we studied how different ligands can have disparate efficacies at Leukotriene B4 receptor (BLT2). By using molecular modeling studies, we predicted that Tyr2716.51 located at TM6 of BLT2 performs as a key trigger for its activation and verified the prediction by site-directed mutagenesis, chemotactic motility studies, which included a chemical derivative of agonist CAY10583. We further identified Asn2756.55 located at TM6 as a weak activation trigger in BLT2 and performed double mutation studies to confirm our computational results. Our results provide strong evidence for the exact mechanism of ligand efficacy at BLT2.

20.
Appl Radiat Isot ; 156: 109015, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32056693

ABSTRACT

For evaluating the counting efficiency of a portal monitor, we use a137Cs radiation point source (1 µCi) to subsequently establish it effective measurable area. Through simulation, we estimate the appropriate distance from potentially contaminated individuals in the scanning queue to the monitoring individual. When this distance is over 10 m, the counting efficiency was below 0.01%. We find that the triage can be applied to roughly 180 individuals per hour during mass casualties.


Subject(s)
Cesium Radioisotopes/analysis , Mass Casualty Incidents , Scintillation Counting/methods , Triage/methods , Humans , Radiation Monitoring/methods
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