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1.
Alcohol Alcohol ; 58(2): 134-141, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36562601

RESUMO

AIMS: Alcohol-associated liver disease (ALD) is a global health problem caused, among other factors, by oxidative stress from the formation of reactive oxygen species (ROS). One important source of ROS is microsomal ethanol metabolism catalyzed by cytochrome P450 2E1 (CYP2E1), which is induced by chronic ethanol consumption. Inhibition of CYP2E1 by clomethiazole (CMZ) decreases oxidative stress in cell cultures and improves ALD in animal studies. Our study aimed to assess the benefits of a CYP2E1 inhibitor (clomethiazole) in detoxification of patients with ALD. METHODS: Open label, randomized controlled clinical trial to study whether CYP2E1 inhibition improves ALD in the patients with alcohol use disorders admitted for alcohol detoxification therapy (ADT). Patients had to have a serum aspartate aminotransferase (AST) activity exceeding twice the upper normal limit at time of admission and be non-cirrhotic defined by fibroscan value <12 kPa. Sixty patients were randomly assigned to ADT with either CMZ or clorazepate (CZP) for 7-10 days in a 1:1 ratio. The chlorzoxazone test of CYP2E1 activity was performed at enrolment and at 2 points during the study. RESULTS: ADT improved hepatic steatosis (controlled attenuation parameter) in both groups significantly. A trend towards a greater improvement in hepatic fat content during ADT (-21.5%) was observed in the CMZ group (252 ± 48 dB/m vs. 321 ± 38 dB/m; P < 0.0001) compared with the CZP group (-13.9%; 273 ± 38 dB/m vs. 317 ± 39 dB/m; P < 0.0001). As already reported, serum AST (P < 0.004) and alanine aminotransferase (ALT) activities (P < 0.0006) significantly decreased in CMZ patients as compared with patients on CZP by the end of hospitalization. A significant correlation was found between AST (P = 0.023), ALT (P = 0.009), GGT (P = 0.039) and CAP. CONCLUSION: This study demonstrates that CMZ improves clinical biomarkers for ALD in humans most likely due to its inhibitory effect on CYP2E1. Because of its addictive potential, CMZ can only be given for a short period of time and therefore other CYP2E1 inhibitors to treat ALD are needed.


Assuntos
Alcoolismo , Fígado Gorduroso , Hepatopatias Alcoólicas , Animais , Humanos , Clormetiazol/metabolismo , Clormetiazol/farmacologia , Clorazepato Dipotássico , Citocromo P-450 CYP2E1 , Alcoolismo/metabolismo , Espécies Reativas de Oxigênio , Fígado , Hepatopatias Alcoólicas/metabolismo , Etanol/farmacologia , Transaminases/metabolismo , Transaminases/farmacologia , Alanina Transaminase
3.
Br J Cancer ; 113(7): 1035-45, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26335606

RESUMO

BACKGROUND: Aberrant DNA methylation is more prominent in proximal compared with distal colorectal cancers. Although a number of methylation markers were identified for colon cancer, yet few are available for rectal cancer. METHODS: DNA methylation differences were assessed by a targeted DNA microarray for 360 marker candidates between 22 fresh frozen rectal tumour samples and 8 controls and validated by microfluidic high-throughput and methylation-sensitive qPCR in fresh frozen and formalin-fixed paraffin-embedded (FFPE) samples, respectively. The CpG island methylator phenotype (CIMP) was assessed by MethyLight in FFPE material from 78 patients with pT2 and pT3 rectal adenocarcinoma. RESULTS: We identified and confirmed two novel three-gene signatures in fresh frozen samples that can distinguish tumours from adjacent tissue as well as from blood with a high sensitivity and specificity of up to 1 and an AUC of 1. In addition, methylation of individual CIMP markers was associated with specific clinical parameters such as tumour stage, therapy or patients' age. Methylation of CDKN2A was a negative prognostic factor for overall survival of patients. CONCLUSIONS: The newly defined methylation markers will be suitable for early disease detection and monitoring of rectal cancer.


Assuntos
Biomarcadores Tumorais/genética , Metilação de DNA , Proteínas de Neoplasias/genética , Neoplasias Retais/genética , Neoplasias Retais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ilhas de CpG , Inibidor p16 de Quinase Dependente de Ciclina , DNA de Neoplasias/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Prognóstico , Análise de Sobrevida
4.
Chemistry ; 21(15): 5769-82, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25727401

RESUMO

Fluoro- and perfluoralkylsulfonyl pentafluoroanilides [HN(C6F5)(SO2X); X = F, CF3, C4F9, C8F17] are a class of imides with two different strongly electron-withdrawing substituents attached to a nitrogen atom. They are NH acids, the unsymmetrical hybrids of the well-known symmetrical bissulfonylimides and bispentafluorophenylamine. The syntheses, the structures of these perfluoroanilides, their solvates, and some selected lithium salts give rise to a structural variety beyond the symmetrical parent compounds. The acidities of representative subsets of these novel NH acids have been investigated experimentally and quantum-chemically and their gas-phase acidities (GAs) are reported, as well as the pKa values of these compounds in acetonitrile (MeCN) and DMSO solution. In quantum chemical investigations with the vertical and relaxed COSMO cluster-continuum models (vCCC/rCCC), the unusual situation is encountered that the DMSO-solvated acid Me2SO-H-N(SO2CF3)2, optimized in the gas phase (vCCC model), dissociates to Me2SO-H(+)-N(SO2CF3)2(-) during structural relaxation and full optimization with the solvation model turned on (rCCC model). This proton transfer underlines the extremely high acidity of HN(SO2CF3)2. The importance of this effect is studied computationally in DMSO and MeCN solution. Usually this effect is less pronounced in MeCN and is of higher importance in the more basic solvent DMSO. Nevertheless, the neglect of the structural relaxation upon solvation causes typical changes in the computational pKa values of 1 to 4 orders of magnitude (4-20 kJ mol(-1)). The results provide evidence that the published experimental DMSO pKa value of HN(SO2CF3)2 should rather be interpreted as the pKa of a Me2SO-H(+)-N(SO2CF3)2(-) contact ion pair.

5.
Bioorg Med Chem ; 19(18): 5529-38, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21873068

RESUMO

A series of analogues of conjugate 1, combining an adamantane-based paclitaxel (taxol) mimetic with colchicine was synthesized and tested for cytotoxicity in a cell-based assay with the human lung carcinoma cell line A549. The most active compounds (10 EC(50) 2 ± 1.0 nM, 23 EC(50) 6 ± 1.4 nM, 26 EC(50) 5 ± 1.8 nM, 28 EC(50) 11 ± 1.7 nM, 30 EC(50) 4.8 ± 0.5 nM) were found to interfere with the microtubule dynamics in an interesting manner. Treatment of the cells with these compounds promoted disassembly of microtubules followed by the formation of stable tubulin clusters. Structure-activity relationships for the analogues of 23 revealed the sensitivity of both cytotoxicity and tubulin clustering ability to the linker length. The presence of adamantane (or another bulky hydrophobic and non-aromatic moiety) in 23 was found to play an important role in the formation of tubulin clusters. Structural requirements for optimal activity have been partially explained by molecular modeling.


Assuntos
Adamantano/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Colchicina/farmacologia , Microtúbulos/efeitos dos fármacos , Tubulina (Proteína)/metabolismo , Adamantano/química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Colchicina/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Microtúbulos/metabolismo , Modelos Moleculares , Estrutura Molecular , Paclitaxel/química , Paclitaxel/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
6.
Dalton Trans ; 46(9): 3014-3024, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-28203677

RESUMO

We present a convenient synthesis of the first silylated bistetrazole via a catalyzed twin [2 + 3] cycloaddition of TMS-azide at cyanogen and its application to access bistetrazolatoborates, structurally characterized by a unique unsaturated ten-membered B2N4C4 heterocyclic system. Furthermore, new borate anions with two pyrazine-2,3-diolato ligands were synthesized from tetrafluoroborate salts and structurally characterized. Their organic cation can be exchanged for Li+via cation exchange. The conceptual relation of these new salts to lithium ion battery bisoxalalatoborate additive LiBOB, a prominent solid electrolyte interface (SEI) generator, is discussed.

7.
Eur J Cancer ; 83: 56-70, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28715695

RESUMO

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. The initiation of protein translation is an important rate-limiting step in eukaryotes and is crucial in many viral infections. Eukaryotic translation initiation factors (eIFs) are involved in the initiation step of protein translation and are linked to the phosphatidylinositol-3-kinases PI3K/AKT/mTOR pathway. Therefore we aimed to investigate a potential role of eIFs in HCC. We herein report on the immunohistochemical expression of the various eIF subunits in 235 cases of virus-related human HCC. Additionally, we used immunoblot analysis to investigate the expression of virus-related HCC and non-virus-related HCC in comparison to controls. Mammalian target of rapamycin (or mechanistic target of rapamycin as it is known now (mTOR) and activated mTOR were significantly increased in chronic hepatitis C (HCV)-associated HCC, in HCC without a viral background, in alcoholic liver disease and Wilson disease. pPTEN, phosphatase and tensin homologue (PTEN) and pAKT showed a significant increase in HBV- and HCV-associated HCC, chronic hepatitis B, HCC without a viral background, alcoholic steatohepatitis (ASH) and Wilson disease. Phosphorylated (p)-eIF2α, eIF2α, eiF3B, eIF3D, eIF3J, p-eIF4B, eIF4G and eIF6 were upregulated in HCV-associated HCC. eIF2α, p-eIF4B, eIF5 and various eIF3 subunits were significantly increased in chronic hepatitis B (HBV)-associated HCC. HCC without viral background displayed a significant increase for the eIF subunits p-2α, 3C, 3I, 4E and 4G. We noticed engraved differences in the expression pattern between chronic hepatitis B and C, HBV- and HCV-associated HCC and non-virus-related HCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Neoplasias Hepáticas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/complicações , Feminino , Hepatite B Crônica/complicações , Hepatite B Crônica/metabolismo , Hepatite C Crônica/complicações , Hepatite C Crônica/metabolismo , Degeneração Hepatolenticular/complicações , Degeneração Hepatolenticular/metabolismo , Humanos , Imuno-Histoquímica , Hepatopatias Alcoólicas/complicações , Hepatopatias Alcoólicas/metabolismo , Neoplasias Hepáticas/complicações , Masculino , Pessoa de Meia-Idade , Subunidades Proteicas/metabolismo , Estudos Retrospectivos
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