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PURPOSE: The CYP2D6 gene exhibits significant polymorphism, contributing to variability in responses to drugs metabolized by CYP2D6. While CYP2D6*2 and CYP2D6*35 are presently designated as alleles encoding normal metabolism, this classification is based on moderate level evidence. Additionally, the role of the formerly called "enhancer" single nucleotide polymorphism (SNP) rs5758550 is unclear. In this study, the impacts of CYP2D6*2, CYP2D6*35 and rs5758550 on CYP2D6 activity were investigated using risperidone clearance as CYP2D6 activity marker. METHODS: A joint parent-metabolite population pharmacokinetic model was used to describe 1,565 serum concentration measurements of risperidone and 9-hydroxyrisperidone in 512 subjects. Risperidone population clearance was modeled as the sum of a CYP2D6-independent clearance term and the partial clearances contributed from each individually expressed CYP2D6 allele or haplotype. In addition to the well-characterized CYP2D6 alleles (*3-*6, *9, *10 and *41), *2, *35 and two haplotypes assigned as CYP2D6*2-rs5758550G and CYP2D6*2-rs5758550A were evaluated. RESULTS: Each evaluated CYP2D6 allele was associated with significantly lower risperidone clearance than the reference normal function allele CYP2D6*1 (p < 0.001). Further, rs5758550 differentiated the effect of CYP2D6*2 (p = 0.005). The haplotype-specific clearances for CYP2D6*2-rs5758550A, CYP2D6*2-rs5758550G and CYP2D6*35 were estimated to 30%, 66% and 57%, respectively, relative to the clearance for CYP2D6*1. Notably, rs5758550 is in high linkage disequilibrium (R2 > 0.85) with at least 24 other SNPs and cannot be assigned as a functional SNP. CONCLUSION: CYP2D6*2 and CYP2D6*35 encode reduced risperidone clearance, and the extent of reduction for CYP2D6*2 is differentiated by rs5758550. Genotyping of these haplotypes might improve the precision of genotype-guided prediction of CYP2D6-mediated clearance.
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OBJECTIVE: Androgen deprivation therapy has been associated with increased cardiovascular risk in men. Experimental studies support that testosterone protects against atherosclerosis, but the target cell remains unclear. T cells are important modulators of atherosclerosis, and deficiency of testosterone or its receptor, the AR (androgen receptor), induces a prominent increase in thymus size. Here, we tested the hypothesis that atherosclerosis induced by testosterone deficiency in male mice is T-cell dependent. Further, given the important role of the thymic epithelium for T-cell homeostasis and development, we hypothesized that depletion of the AR in thymic epithelial cells will result in increased atherosclerosis. APPROACH AND RESULTS: Prepubertal castration of male atherosclerosis-prone apoE-/- mice increased atherosclerotic lesion area. Depletion of T cells using an anti-CD3 antibody abolished castration-induced atherogenesis, demonstrating a role of T cells. Male mice with depletion of the AR specifically in epithelial cells (E-ARKO [epithelial cell-specific AR knockout] mice) showed increased thymus weight, comparable with that of castrated mice. E-ARKO mice on an apoE-/- background displayed significantly increased atherosclerosis and increased infiltration of T cells in the vascular adventitia, supporting a T-cell-driven mechanism. Consistent with a role of the thymus, E-ARKO apoE-/- males subjected to prepubertal thymectomy showed no atherosclerosis phenotype. CONCLUSIONS: We show that atherogenesis induced by testosterone/AR deficiency is thymus- and T-cell dependent in male mice and that the thymic epithelial cell is a likely target cell for the antiatherogenic actions of testosterone. These insights may pave the way for new therapeutic strategies for safer endocrine treatment of prostate cancer.
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Aorta/metabolismo , Doenças da Aorta/prevenção & controle , Aterosclerose/prevenção & controle , Células Epiteliais/metabolismo , Linfócitos T/metabolismo , Testosterona/metabolismo , Timo/metabolismo , Animais , Aorta/patologia , Doenças da Aorta/genética , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Modelos Animais de Doenças , Células Epiteliais/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Orquiectomia , Receptores Androgênicos/deficiência , Receptores Androgênicos/genética , Testosterona/deficiência , Timectomia , Timo/patologia , Timo/cirurgiaRESUMO
Hepatocytes are dynamic cells that, upon injury, can alternate between nondividing differentiated and dedifferentiated proliferating states in vivo. However, in two-dimensional cultures, primary human hepatocytes (PHHs) rapidly dedifferentiate, resulting in loss of hepatic functions that significantly limits their usefulness as an in vitro model of liver biology, liver diseases, as well as drug metabolism and toxicity. Thus, understanding the underlying mechanisms and stalling of the dedifferentiation process would be highly beneficial to establish more-accurate and relevant long-term in vitro hepatocyte models. Here, we present comprehensive analyses of whole proteome and transcriptome dynamics during the initiation of dedifferentiation during the first 24 hours of culture. We report that early major rearrangements of the noncoding transcriptome, hallmarked by increased expression of small nucleolar RNAs, long noncoding RNAs, microRNAs (miRNAs), and ribosomal genes, precede most changes in coding genes during dedifferentiation of PHHs, and we speculated that these modulations could drive the hepatic dedifferentiation process. To functionally test this hypothesis, we globally inhibited the miRNA machinery using two established chemically distinct compounds, acriflavine and poly-l-lysine. These inhibition experiments resulted in a significantly impaired miRNA response and, most important, in a pronounced reduction in the down-regulation of hepatic genes with importance for liver function. Thus, we provide strong evidence for the importance of noncoding RNAs, in particular, miRNAs, in hepatic dedifferentiation, which can aid the development of more-efficient differentiation protocols for stem-cell-derived hepatocytes and broaden our understanding of the dynamic properties of hepatocytes with respect to liver regeneration. CONCLUSION: miRNAs are important drivers of hepatic dedifferentiation, and our results provide valuable information regarding the mechanisms behind liver regeneration and possibilities to inhibit dedifferentiation in vitro. (Hepatology 2016;64:1743-1756).
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Desdiferenciação Celular/genética , Hepatócitos/fisiologia , MicroRNAs/fisiologia , Adulto , Idoso , Células Cultivadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , TranscriptomaRESUMO
CYP2W1 is expressed in the course of development of the gastrointestinal tract, silenced after birth in intestine and colon by epigenetic modifications, but activated following demethylation in colorectal cancer (CRC). The expression levels in CRC positively correlate with the degree of malignancy, are higher in metastases and are predictive of colon cancer survival. The CYP2W1 transcripts have been detected also in hepatocellular carcinoma, adrenocortical carcinoma, childhood rhabdomyosarcoma and breast cancer; however, here the protein expression remains to be confirmed. The CYP2W1 enzyme has an inverted orientation in the endoplasmic reticulum membrane, as compared to other cytochrome P450s and its immediate electron donor is unknown. Several lipid ligands have been proposed as endogenous substrates, among which retinol derivatives appear to have the highest affinities. However, the role of CYP2W1 in the endogenous and tumor localized metabolism of retinol derivatives has yet to be clarified. Indolines constitute high affinity exogenous compounds and specific chloromethylindolines have been shown to be activated by CYP2W1 into cytotoxic products in vitro and also in vivo, inhibiting the growth of human colon tumors in a mouse xenograft model. The CRC specific localization of CYP2W1 and its effective prodrug activation makes it a very promising target for future development of cancer therapeutics.
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Família 2 do Citocromo P450/metabolismo , Regulação Enzimológica da Expressão Gênica , Pró-Fármacos/metabolismo , Animais , Biotransformação , Família 2 do Citocromo P450/genética , Epigênese Genética , Humanos , Indóis/metabolismo , Neoplasias/metabolismo , Vitamina A/análogos & derivados , Vitamina A/metabolismoRESUMO
BACKGROUND: Cytomegalovirus (CMV) is associated with an increased risk of cardiac allograft vasculopathy (CAV), the major limiting factor for long-term survival after heart transplantation (HTx). The purpose of this study was to evaluate the impact of CMV infection during long-term follow-up after HTx. METHODS: A retrospective, single-centre study analyzed 226 HTx recipients (mean age 45 ± 13 years, 78 % men) who underwent transplantation between January 1988 and December 2000. The incidence and risk factors for CMV infection during the first year after transplantation were studied. Risk factors for CAV were included in an analyses of CAV-free survival within 10 years post-transplant. The effect of CMV infection on the grade of CAV was analyzed. RESULTS: Survival to 10 years post-transplant was higher in patients with no CMV infection (69 %) compared with patients with CMV disease (55 %; p = 0.018) or asymptomatic CMV infection (54 %; p = 0.053). CAV-free survival time was higher in patients with no CMV infection (6.7 years; 95 % CI, 6.0-7.4) compared with CMV disease (4.2 years; CI, 3.2-5.2; p < 0.001) or asymptomatic CMV infection (5.4 years; CI, 4.3-6.4; p = 0.013). In univariate analysis, recipient age, donor age, coronary artery disease (CAD), asymptomatic CMV infection and CMV disease were significantly associated with CAV-free survival. In multivariate regression analysis, CMV disease, asymptomatic CMV infection, CAD and donor age remained independent predictors of CAV-free survival at 10 years post-transplant. CONCLUSIONS: CAV-free survival was significantly reduced in patients with CMV disease and asymptomatic CMV infection compared to patients without CMV infection. These findings highlight the importance of close monitoring of CMV viral load and appropriate therapeutic strategies for preventing asymptomatic CMV infection.
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Infecções por Citomegalovirus/epidemiologia , Citomegalovirus/patogenicidade , Sobrevivência de Enxerto , Transplante de Coração , Fatores Etários , Aloenxertos , Doença da Artéria Coronariana/complicações , Infecções por Citomegalovirus/patologia , Infecções por Citomegalovirus/prevenção & controle , Infecções por Citomegalovirus/virologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Doadores de Tecidos/estatística & dados numéricos , Carga ViralRESUMO
INTRODUCTION: Metastatic disease is a major cause of death in patients with colorectal cancer (CRC). We have previously investigated expression of an orphan cytochrome P450 (CYP) enzyme, CYP2W1, and found high expression in about one third of colorectal tumors. CYP2W1 has proven to metabolize duocarmycin analogs into cytotoxic substances, compounds that in xenografts of CRC cells expressing CYP2W1 completely inhibit tumor growth. This study was designed to evaluate whether the enzyme is expressed in primary CRC and corresponding metastases. MATERIAL AND METHODS: Samples from primary tumors, corresponding lymph node metastases and liver metastases from 96 patients were collected and analyzed by immunohistochemistry. Data regarding patient's demographics, tumor characteristics and survival were also collected. RESULTS: Out of 96 patients, 25 (26%) had high CYP2W1 expression in the primary tumor and 46 (48%) showed high levels in the liver metastasis. In total 59 patients had lymph node metastases, and 31% of them had high CYP2W1 expression. When comparing the expression in primary tumor with that of the first liver metastasis, the increase in expression was statistically significant (p = 0.005). CONCLUSION: High CYP2W1 expression is seen in 26% of primary CRC and in 48% of corresponding liver metastases. This opens possibilities for new targeted therapies to metastatic CRC in the future.
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Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Sistema Enzimático do Citocromo P-450/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Idoso , Estudos de Coortes , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/cirurgia , Família 2 do Citocromo P450 , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Linfonodos/patologia , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Análise de SobrevidaRESUMO
BACKGROUND: Nurses experience insufficient medication knowledge; particularly in drug dose calculations, but also in drug management and pharmacology. The weak knowledge could be a result of deficiencies in the basic nursing education, or lack of continuing maintenance training during working years. The aim of this study was to compare the medication knowledge, certainty and risk of error between graduating bachelor students in nursing and experienced registered nurses. METHODS: Bachelor students in closing term and registered nurses with at least one year job experience underwent a multiple choice test in pharmacology, drug management and drug dose calculations: 3x14 questions with 3-4 alternative answers (score 0-42). Certainty of each answer was recorded with score 0-3, 0-1 indicating need for assistance. Risk of error was scored 1-3, where 3 expressed high risk: being certain that a wrong answer was correct. The results are presented as mean and (SD). RESULTS: Participants were 243 graduating students (including 29 men), aged 28.2 (7.6) years, and 203 registered nurses (including 16 men), aged 42.0 (9.3) years and with a working experience of 12.4 years (9.2). The knowledge among the nurses was found to be superior to that of the students: 68.9%(8.0) and 61.5%(7.8) correct answers, respectively, (p < 0.001). The difference was largest in drug management and dose calculations. The improvement occurred during the first working year. The nurses expressed higher degree of certainty and the risk of error was lower, both overall and for each topic (p < 0.01). Low risk of error was associated with high knowledge and high sense of coping (p < 0.001). CONCLUSIONS: The medication knowledge among experienced nurses was superior to bachelor students in nursing, but nevertheless insufficient. As much as 25% of the answers to the drug management questions would lead to high risk of error. More emphasis should be put into the basic nursing education and in the introduction to medication procedures in clinical practice to improve the nurses' medication knowledge and reduce the risk of error.
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Conhecimentos, Atitudes e Prática em Saúde , Erros de Medicação/prevenção & controle , Enfermeiras e Enfermeiros , Estudantes de Enfermagem , Adulto , Idoso , Cálculos da Dosagem de Medicamento , Educação em Enfermagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Inquéritos e Questionários , Adulto JovemRESUMO
Reduction of hydroxylamines and amidoximes is important for drug activation and detoxification of aromatic and heterocyclic amines. Such a reductase system was previously found to be of high activity in adipose tissue and liver, and furthermore, in vitro studies using recombinant truncated and purified enzymes suggested the participation of cytochrome b(5) reductase (CYB5R), cytochrome b(5) (CYB5), and molybdenum cofactor sulfurase C-terminal containing 1 and 2 (MOSC1 and -2). Here, we show that purified rat liver outer mitochondrial membrane contains high amidoxime reductase activity and that MOSC2 is exclusively localized to these membranes. Moreover, using the same membrane fraction, we could show direct binding of a radiolabeled benzamidoxime substrate to MOSC2. Following differentiation of murine 3T3-L1 cells into mature adipocytes, the MOSC2 levels as well as the amidoxime reductase activity were increased, indicating that the enzyme is highly regulated under lipogenic conditions. siRNA-mediated down-regulation of MOSC2 and the mitochondrial form of cytochrome b(5) type B (CYB5B) significantly inhibited the reductase activity in the differentiated adipocytes, whereas down-regulation of MOSC1, cytochrome b(5) type A (CYB5A), CYB5R1, CYB5R2, or CYB5R3 had no effect. Down-regulation of MOSC2 caused impaired lipid synthesis. These results demonstrate for the first time the direct involvement of MOSC2 and CYB5B in the amidoxime reductase activity in an intact cell system. We postulate the presence of a novel reductive enzyme system of importance for lipid synthesis that is exclusively localized to the outer mitochondrial membrane and is composed of CYB5B, MOSC2, and a third unknown component (a CYB5B reductase).
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Adipócitos/metabolismo , Proteínas de Transporte/metabolismo , Citocromos b5/metabolismo , Hemeproteínas/metabolismo , Lipídeos/biossíntese , Mitocôndrias Hepáticas/enzimologia , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Células 3T3-L1 , Adipócitos/citologia , Adipogenia/fisiologia , Animais , Diferenciação Celular/fisiologia , Fracionamento Celular , Citocromos b5/genética , Feminino , Proteínas Ligantes de Grupo Heme , Inativação Metabólica/fisiologia , Camundongos , Membranas Mitocondriais/enzimologia , Proteínas Mitocondriais/genética , Oxirredutases/genética , RNA Interferente Pequeno/farmacologia , Ratos , XenobióticosRESUMO
BACKGROUND: Cytomegalovirus (CMV) is the most common opportunistic infection following lung transplantation. CMV replication in the lung allograft is described as accelerating the development of bronchiolitis obliterans syndrome (BOS). Finding a strategy to prevent CMV infection is an important issue. METHODS: We performed a retrospective, single-centre study of 114 lung transplant recipients (LTRs) who underwent lung transplantation from January 2001 to December 2006. In a smaller cohort of 88 CMV seropositive (R+) LTRs, three months of valganciclovir prophylaxis (2004-2006) was compared to three months of oral ganciclovir (2001-2003) with respect to the incidence of CMV infection/disease, the severity of CMV disease, acute rejection, BOS-free 4 year survival and 4 year survival. In the whole group of 114 LTRs the impact of CMV infection on long-term survival (BOS free 4 year survival and 6 year survival) was assessed. RESULTS: For the cohort of 88 CMV seropositive LTRs, the incidence of CMV infection/disease at one year was lower in the valganciclovir group compared to the ganciclovir group (24% vs. 54%, p = 0.003). There was a tendency towards reduced CMV disease, from 33% to 20% and a significant lower incidence of asymptomatic CMV infection (22% vs. 4%, p = 0.005). A lower incidence of acute rejection was observed in the valganciclovir group. However, there was no significant difference between the two groups in BOS free 4 year survival and 4 year survival.For the entire group of 114 LTRs, BOS-free 4 year survival for recipients with CMV disease was (32%, p = 0.005) and among those with asymptomatic CMV infection (36%, p = 0.061) as compared with patients without CMV infection (69%). Six year survival was lower among patients with CMV disease, (64%, p = 0.042) and asymptomatic CMV infection (55%, p = 0.018) than patients without CMV infection (84%). CONCLUSIONS: A lower incidence of CMV infection/disease and acute rejections was observed with valganciclovir (3 months) when compared to oral ganciclovir (3 months). The long-term impact of CMV infection/disease was significant for BOS-free survival and survival.
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Antivirais/uso terapêutico , Infecções por Citomegalovirus/prevenção & controle , Ganciclovir/análogos & derivados , Rejeição de Enxerto/prevenção & controle , Transplante de Pulmão/efeitos adversos , Infecções Oportunistas/prevenção & controle , Adolescente , Adulto , Idoso , Antibioticoprofilaxia , Bronquiolite Obliterante/tratamento farmacológico , Bronquiolite Obliterante/epidemiologia , Bronquiolite Obliterante/prevenção & controle , Bronquiolite Obliterante/virologia , Criança , Pré-Escolar , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/isolamento & purificação , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/virologia , Feminino , Ganciclovir/uso terapêutico , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/tratamento farmacológico , Infecções Oportunistas/epidemiologia , Infecções Oportunistas/virologia , Estudos Retrospectivos , Valganciclovir , Adulto JovemRESUMO
The aim was to describe and compare nursing assistants', enrolled nurses' and registered nurses' perceptions of quality of care, working conditions, competence and personal health in older peoples' care. Altogether 70 nursing assistants, 163 enrolled nurses and 198 registered nurses completed a questionnaire comprising Quality from the Patient's Perspective modified for caregivers, Creative Climate Questionnaire, Stress of Conscience Questionnaire, items on education and competence and Health Index. The caregivers reported higher perceived reality of quality of care in medical-technical competence and physical-technical conditions than in identity-oriented approach and socio-cultural atmosphere. In subjective importance, the highest rating was assessed in one of the physical-technical items. The organisational climate was for three of the dimensions rather close/reached the value for a creative climate, for seven dimensions close to a stagnant climate. In perceived stress of conscience, there were low values. Nursing assistants had lower values than enrolled nurses and registered nurses. The caregivers reported highest values regarding previous education making them feel safe at work and lowest value on the item about education increasing the ability for a scientific attitude. Registered nurses could use knowledge in practice and to a higher degree than nursing assistants/enrolled nurses reported a need to gain knowledge, but the latter more often received education during working hours. The health index among caregivers was high, but registered nurses scored lower on emotional well-being than nursing assistants/enrolled nurses. The caregivers' different perceptions of quality of care and work climate need further attention. Although stress of conscience was low, it is important to acknowledge what affected the caregivers work in a negative way. Attention should be paid to the greater need for competence development among registered nurses during working hours.
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Cuidadores , Competência Clínica , Serviços de Saúde para Idosos , Nível de Saúde , Qualidade da Assistência à Saúde , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SuéciaRESUMO
PURPOSE: The basis of high intersubject variability of propofol metabolism is unclear. Therefore, we examined the influence of genetic polymorphisms of the key metabolizing enzymes cytochrome P450 2B6 (CYP2B6) and uridine diphosphate (UDP)-glucuronosyltransferase 1A9 (UGT1A9), age, and sex on propofol biotransformation in vitro and in vivo. METHODS: Plasma concentrations of propofol, 4-hydroxypropofol, and their glucuronides were measured over 20 min in 105 patients after a single intravenous bolus of propofol. Propofol 4-hydroxylation activity, genotypes, and content of CYP2B6 protein in 68 human livers were determined. The common single nucleotide polymorphisms (SNPs) for the CYP2B6 and UGT1A9 genes were analyzed by polymerase chain reaction (PCR). RESULTS: Plasma levels of propofol metabolites showed high interindividual variability (range of coefficient of variation 89-128%). This was supported by in vitro data showing similar variability of propofol 4-hydroxylation in liver microsomes and 1.9-fold higher CYP2B6 protein content in the livers from women. No significant relationships were revealed between the SNPs studied and propofol metabolism. However, patients' sex had a pronounced effect on propofol metabolism. Thus, women had higher amounts of propofol glucuronide (1.25-fold; p = 0.03), 4-hydroxypropofol-1-glucuronide (2.1-fold; p = 0.0009), and 4-hydroxypropofol-4-glucuronide (1.7-fold; p = 0.02) as shown by the weight-corrected area under the time-plasma concentration curve of metabolites. Additionally, the sexual dimorphism in 4-hydroxypropofol glucuronidation was prominent in the 35- to 64-year-old subgroup. CONCLUSIONS: No significant effects of CYP2B6 and UGT1A9 SNPs or age on propofol metabolism were revealed in this pilot study, but there was a pronounced effect of sex, a finding that indicates an important factor for the previously described sex difference in systemic clearance of propofol seen.
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Anestésicos Intravenosos/farmacocinética , Propofol/farmacocinética , Adolescente , Adulto , Idoso , Anestésicos Intravenosos/sangue , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP2B6 , Feminino , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Humanos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Oxirredutases N-Desmetilantes/genética , Oxirredutases N-Desmetilantes/metabolismo , Polimorfismo de Nucleotídeo Único , Propofol/sangue , Fatores Sexuais , UDP-Glucuronosiltransferase 1A , Adulto JovemRESUMO
During pharmacotherapy, knowledge about the actual drug and metabolite concentrations in plasma is often critical. Individual dose adjustments can be performed based on pre-emptive genotyping of certain absorption, distribution, metabolism, and excretion (ADME) genes but also using therapeutic drug monitoring (TDM). Analyses of liquid biopsies for tumor-derived components are well-established and have been found to be a good complement to biopsy examinations. Recently, liquid biopsy-based quantification of cell-free RNA (cfRNA) in plasma exosomes was proposed as a proxy measurement for the expression of different hepatic ADME genes and for the rate of drug metabolism, constituting an alternative to TDM. In this study, we validated these findings by examining the correlation between mRNA expression of eight different CYP genes in liver and the corresponding rate of enzyme-specific drug metabolism in 96 donor-matched liver samples. Analyses of CYP-dependent drug metabolism in liver microsomes in comparison to the level of mRNA expression for the different CYP genes revealed a mean Pearson correlation coefficient of 0.28. The highest correlations (0.33-0.34) were obtained for CYP2D6 and CYP3A4 and the weakest correlations were observed for CYP1A2 and CYP2B6 (0.18-0.21). In all cases, the correlations obtained were too weak to demonstrate a predictive relationship, likely due to different regulatory and post-translational events controlling the rate of enzyme activity. Our results reinforce the notion that, whilst liquid biopsy-based approaches might have utility for prediction of hepatic CYP protein expression, they are not currently an important substitute for TDM.
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Ácidos Nucleicos Livres , Citocromo P-450 CYP1A2 , Humanos , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP2D6/metabolismo , Monitoramento de Medicamentos , Citocromo P-450 CYP2B6/metabolismo , Microssomos Hepáticos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Biópsia Líquida , Ácidos Nucleicos Livres/metabolismoRESUMO
Testosterone deficiency in men is associated with increased atherosclerosis burden and increased cardiovascular risk. In male mice, testosterone deficiency induced by castration increases atherosclerosis as well as mature B cell numbers in spleen. As B cells are potentially pro-atherogenic, we hypothesized that there may be a link between these effects. To address whether mature B cell deficiency alter the atherogenic response to castration, we studied B cell-deficient µMT and genotype control male mice on an atherosclerosis-prone Apoe-/- background that were castrated or sham-operated pre-pubertally and fed a high-fat diet between 8 and 16 weeks of age to accelerate atherosclerosis development. Genotype did not affect the effects of castration on body weight or weights of fat depots and there were no differences in serum cholesterol levels across the four groups. Atherosclerosis assessed by quantification of lesion area in serial sections of the aortic root was significantly increased by castration and by the µMT mutation, with no significant interaction between genotype and surgery. In conclusion, castration evokes a similar atherogenic response in B cell-deficient µMT and control mice. These data suggest that atherogenesis following castration is unrelated to the effects of androgens on mature B cell numbers.
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Aterosclerose , Animais , Aorta/patologia , Apolipoproteínas E , Aterosclerose/genética , Linfócitos B/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Orquiectomia , Testosterona/efeitos adversosRESUMO
The genetic background for interindividual variability of the polymorphic CYP2D6 enzyme activity remains incompletely understood and the role of NFIB genetic polymorphism for this variability was evaluated in this translational study. We investigated the effect of NFIB expression in vitro using 3D liver spheroids, Huh7 cells, and the influence of the NFIB polymorphism on metabolism of risperidone in patients in vivo. We found that NFIB regulates several important pharmacogenes, including CYP2D6. NFIB inhibited CYP2D6 gene expression in Huh7 cells and NFIB expression in livers was predominantly nuclear and reduced at the mRNA and protein level in carriers of the NFIB rs28379954 T>C allele. Based on 604 risperidone treated patients genotyped for CYP2D6 and NFIB, we found that the rate of risperidone hydroxylation was elevated in NFIB rs28379954 T>C carriers among CYP2D6 normal metabolizers, resulting in a similar rate of drug metabolism to what is observed in CYP2D6 ultrarapid metabolizers, with no such effect observed in CYP2D6 poor metabolizers lacking functional enzyme. The results indicate that NFIB constitutes a novel nuclear factor in the regulation of cytochrome P450 genes, and that its polymorphism is a predictor for the rate of CYP2D6 dependent drug metabolism in vivo.
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Antipsicóticos , Risperidona , Antipsicóticos/uso terapêutico , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Genótipo , Humanos , Fígado/metabolismo , Fatores de Transcrição NFI/genética , Risperidona/uso terapêuticoRESUMO
Androgen deprivation therapy of prostate cancer, which suppresses serum testosterone to castrate levels, is associated with increased risk of heart failure. Here we tested the hypothesis that castration alters cardiac energy substrate uptake, which is tightly coupled to the regulation of cardiac structure and function. Short-term (3-4 weeks) surgical castration of male mice reduced the relative heart weight. While castration did not affect cardiac function in unstressed conditions, we observed reductions in heart rate, stroke volume, cardiac output, and cardiac index during pharmacological stress with dobutamine in castrated vs sham-operated mice. Experiments using radiolabeled lipoproteins and glucose showed that castration shifted energy substrate uptake in the heart from lipids toward glucose, while testosterone replacement had the opposite effect. There was increased expression of fetal genes in the heart of castrated mice, including a strong increase in messenger RNA and protein levels of ß-myosin heavy chain (MHC), the fetal isoform of MHC. In conclusion, castration of male mice induces metabolic remodeling and expression of the fetal gene program in the heart, in association with a reduced cardiac performance during pharmacological stress. These findings may be relevant for the selection of treatment strategies for heart failure in the setting of testosterone deficiency.
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α-Dystroglycan is an extracellular adhesion protein that is known to interact with different ligands. The interaction is thought to stabilize the integrity of the plasma membrane. The N-terminal part of α-dystroglycan may be proteolytically processed to generate a small 38 kDa protein (α-DG-N). The physiological significance of α-DG-N is unclear but has been suggested to be involved in nerve regeneration and myelination and to function as a potential biomarker for neurodegenerative and neuromuscular diseases. In this report we show that α-DG-N is released into different body fluids, such as lachrimal fluid, cerebrospinal fluid (CSF), urine and plasma. To investigate the significance of α-DG-N in CSF we examined the levels of α-DG-N and known neurodegenerative markers in CSF from patients diagnosed with Lyme neuroborreliosis (LNB) and healthy controls. In untreated acute phase LNB patients, 67% showed a significant increase of CSF α-DG-N compared to healthy controls. After treatment with antibiotics the CSF α-DG-N levels were normalized in the LNB patients.
Assuntos
Distroglicanas/líquido cefalorraquidiano , Distroglicanas/metabolismo , Neuroborreliose de Lyme/líquido cefalorraquidiano , Adulto , Idoso , Biomarcadores/líquido cefalorraquidiano , Distroglicanas/química , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estrutura Terciária de ProteínaRESUMO
BACKGROUND: Medication errors are often involved in reported adverse events. Drug therapy, prescribed by physicians, is mostly carried out by nurses, who are expected to master all aspects of medication. Research has revealed the need for improved knowledge in drug dose calculation, and medication knowledge as a whole is poorly investigated. The purpose of this survey was to study registered nurses' medication knowledge, certainty and estimated risk of errors, and to explore factors associated with good results. METHODS: Nurses from hospitals and primary health care establishments were invited to carry out a multiple-choice test in pharmacology, drug management and drug dose calculations (score range 0-14). Self-estimated certainty in each answer was recorded, graded from 0 = very uncertain to 3 = very certain. Background characteristics and sense of coping were recorded. Risk of error was estimated by combining knowledge and certainty scores. The results are presented as mean (±SD). RESULTS: Two-hundred and three registered nurses participated (including 16 males), aged 42.0 (9.3) years with a working experience of 12.4 (9.2) years. Knowledge scores in pharmacology, drug management and drug dose calculations were 10.3 (1.6), 7.5 (1.6), and 11.2 (2.0), respectively, and certainty scores were 1.8 (0.4), 1.9 (0.5), and 2.0 (0.6), respectively. Fifteen percent of the total answers showed a high risk of error, with 25% in drug management. Independent factors associated with high medication knowledge were working in hospitals (p < 0.001), postgraduate specialization (p = 0.01) and completion of courses in drug management (p < 0.01). CONCLUSIONS: Medication knowledge was found to be unsatisfactory among practicing nurses, with a significant risk for medication errors. The study revealed a need to improve the nurses' basic knowledge, especially when referring to drug management.
Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Erros de Medicação , Medição de Risco , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Erros de Medicação/prevenção & controle , Pessoa de Meia-Idade , Noruega , Recursos Humanos de Enfermagem/psicologia , AutoeficáciaRESUMO
AIM: The aim was to describe research utilisation among newly graduated nurses and to explore critical thinking dispositions and other individual and contextual factors as possible predictors for research use. BACKGROUND: Nurses are expected to be research users, and variations in research utilisation are explained by individual and contextual factors. To our knowledge, critical thinking dispositions have not earlier been explored as predictors for research use. DESIGN: A cross-sectional design was chosen. METHODS: Data collection was carried out from October 2006 to April 2007 using the Research Utilization Questionnaire (RUQ) and the California Critical Thinking Disposition Inventory (CCTDI). The response rate was 33% (n =617). Pearson's chi-square test and regression analyses were used for statistical calculations. RESULTS: The respondents reported a positive attitude towards research, but only 24% (n = 148) were defined as research users. A significantly higher proportion of research users reported high critical thinking scores. Critical thinking explained 20% of the variance in attitude towards research and 11% of the variance in research use. Availability and support to implement research findings was the second strongest predictor for research use. CONCLUSIONS: Critical thinking, a significant predictor for attitude towards research and for the use of research, should be recognised and strengthened in nursing education and clinical practice. Contextual factors seem to be important for newly graduated nurses' use of research. RELEVANCE TO CLINICAL PRACTICE: Nurse leaders play an important role in nurturing newly graduated nurses' critical thinking and assisting them in transferring their positive attitude towards research into research use. Nurse educators play a significant role in supporting, challenging and supervising nursing students to be critical thinkers and strong believers in research utilisation.
Assuntos
Enfermeiras e Enfermeiros/psicologia , Pesquisa em Enfermagem , Pensamento , Estudos Transversais , Humanos , Inquéritos e QuestionáriosRESUMO
Drug-induced liver injury is a common reason for drug attrition in late clinical phases, and even for post-launch withdrawals. As a consequence, there is a broad consensus in the pharmaceutical industry, and within regulatory authorities, that a significant improvement of the current in vitro test methodologies for accurate assessment and prediction of such adverse effects is needed. For this purpose, appropriate in vivo-like hepatic in vitro models are necessary, in addition to novel sources of human hepatocytes. In this report, we describe recent and ongoing research toward the use of human embryonic stem cell (hESC)-derived hepatic cells, in conjunction with new and improved test methods, for evaluating drug metabolism and hepatotoxicity. Recent progress on the directed differentiation of human embryonic stem cells to the functional hepatic phenotype is reported, as well as the development and adaptation of bioreactors and toxicity assay technologies for the testing of hepatic cells. The aim of achieving a testing platform for metabolism and hepatotoxicity assessment, based on hESC-derived hepatic cells, has advanced markedly in the last 2-3 years. However, great challenges still remain, before such new test systems could be routinely used by the industry. In particular, we give an overview of results from the Vitrocellomics project (EU Framework 6) and discuss these in relation to the current state-of-the-art and the remaining difficulties, with suggestions on how to proceed before such in vitro systems can be implemented in industrial discovery and development settings and in regulatory acceptance.
Assuntos
Alternativas aos Testes com Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Células-Tronco Embrionárias , Hepatócitos/efeitos dos fármacos , Testes de Toxicidade/métodos , Animais , Reatores Biológicos , Biotransformação , Diferenciação Celular , Linhagem Celular , Respiração Celular , Indução Enzimática , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Redes e Vias Metabólicas , RatosRESUMO
UNLABELLED: The aim of this study was to describe the nursing staff's opinion of caring for older persons with dementia with the focus on causes of falls, fall-preventing interventions, routines of documentation and report and the nursing staff's experiences and reactions when fall incidents occur. A further aim was to compare these areas between registered nurses (RNs) and enrolled nurses (ENs) and staff with ≤5 and >5 years of employment in the care units in question. BACKGROUND: Falls are common among older people and persons with dementia constitute an additional risk group. METHODS: The study had a cross-sectional design and included nursing staff (n = 63, response rate 66%) working in four special care units for older persons with dementia. Data collection was conducted with a questionnaire consisting of 64 questions. RESULTS: The respondents reported that the individuals' mental and physical impairment constitute the most frequent causes of falls. The findings also revealed a lack of, or uncertainty about, routines of documentation and reporting fall-risk and fall-preventing interventions. Respondents who had been employed in the care units more than five years reported to a higher degree that colours and material on floors caused falls. RNs considered the residents' autonomy and freedom of movement as a cause of falls to a significantly higher degree than ENs. RNs also reported a significantly longer time than ENs before fall incidents were discovered, and they used conversation and closeness as fall-preventing interventions to a significantly higher degree than ENs. CONCLUSIONS: Individual factors were the most common causes to falls according to the nursing staff. RNs used closeness and dialog as interventions to a significantly higher degree to prevent falls than ENs. Caring of for older people with dementia consisted of a comprehensive on-going assessment by the nursing staff to balance the residents' autonomy-versus-control to minimise fall-risk. This ethical dilemma should initiate development of feasible routines of systematic risk-assessment, report and documentation.