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1.
N C Med J ; 83(3): 197-202, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35504705

RESUMO

North Carolina implemented a rapid statewide COVID-19 vaccine strategy that focused on vaccinating people quickly and equitably. We describe the sociodemographic factors associated with COVID-19 vaccine uptake in North Carolina and how these factors were considered in communication as well as community and health care provider engagement in the COVID-19 response.


Assuntos
Vacinas contra COVID-19 , COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pessoal de Saúde , Humanos , North Carolina/epidemiologia , Vacinação
2.
J Proteome Res ; 10(7): 3123-35, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21604690

RESUMO

The present study was undertaken to identify proteins interacting with PrP(C) that could provide new insights into its physiological functions and pathological role. Human PrP(C) was expressed in prion protein-deficient murine hippocampus (HpL3-4) neuronal cells. The PrP(C) along with its interacting proteins were affinity purified using STrEP-Tactin-chromatography, in-gel digested, and identified by Q-TOF MS/MS analysis. Forty-three proteins appeared to interact with PrP(C) in this neuronal cell line. Of these, 15 were already known for their interaction with PrP(C) or PrP(Sc), while 28 new proteins were identified. Interaction of a novel interacting partner of GTPase family-Rab7a, having a suggested role in vesicle trafficking, was further investigated using confocal laser scanning microscopy and reverse coimmunoprecipitation. Both reverse coimmunoprecipitation and immunofluorescence results confirmed potential interaction of Rab7a with the PrP(C). siRNA against the Rab7a gene decreased expression of Rab7a protein, in PrP(C) expressing HpL3-4 and SH-SY5Y cells. This depleted Rab7a expression led to the enhanced accumulation of PrP(C) in Rab9 positive endosomal compartments and consequently an increased colocalization between PrP(C)/Rab9. However, the Rab9 accumulated PrP(C) remained sensitive to proteinase-K digestion. The work described demonstrated for the first time that Rab7a interacts with PrP(C) and highlighted the involvement of endosomal compartments in the trafficking and regulation of PrP(C).


Assuntos
Endossomos/metabolismo , Neurônios/metabolismo , Proteínas PrPC , Mapeamento de Interação de Proteínas/métodos , Proteômica/métodos , Proteínas rab de Ligação ao GTP , Animais , Linhagem Celular , Endossomos/genética , Imunofluorescência , Expressão Gênica , Inativação Gênica/efeitos dos fármacos , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Imunoprecipitação , Camundongos , Microscopia Confocal , Neurônios/citologia , Proteínas PrPC/genética , Proteínas PrPC/metabolismo , RNA Interferente Pequeno/farmacologia , Transdução de Sinais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , proteínas de unión al GTP Rab7
3.
J Clin Apher ; 26(4): 167-73, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21500250

RESUMO

Lipid-apheresis (LA) is thought to improve microcirculation. However, limited data are available on the effects on peripheral microcirculation. We investigated upper limb microcirculation of 22 patients undergoing regular LA on a weekly basis before and after LA. Using standardized semiquantitative scales, we analyzed blood flow, vasomotor function, and erythrocyte aggregation by capillary microscopy. In addition, capillary blood flow in quiescence and under heat and cryo-stress was evaluated by photoplethysmographic and laser Doppler anemometry. Moreover, levels of vasoactive mediators adrenalin, noradrenalin, endothelin-1 (ET-1), atrial natriuretic peptide (ANP), asymmetrical dimethyl-arginine (ADMA), as well as total protein and fibrinogen were measured. We found a significant increase in blood flow, the number of perfused capillaries and an improvement of erythrocyte aggregation by capillary microscopy. Using laser Doppler anemometry, we were able to show that this increase was predominantly located in the superficial layer capillaries (Δ44.53 ± 135.81%, n.s.) and less so in deeper layer arterioles (Δ2.75 ± 24.84%, n.s.). Vascular response to heat and cryo stress was also improved after LA but failed to reach significance. LA significantly reduced levels of epinephrin (-33 ± 39.2%), ANP (-28.8 ± 20.2%), ADMA (-74.1 ± 23%), and fibrinogen (-45.4 ± 19.7%) when comparing before LA and after LA values. In summary, we found an improvement in the microcirculation of the upper limbs under LA, which may result from a decrease of vasoconstrictors, improvement of vasomotor function, and a decrease in blood viscosity or erythrocyte aggregation.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Hipercolesterolemia/terapia , Lipídeos/sangue , Lipídeos/isolamento & purificação , Microcirculação/fisiologia , Adulto , Idoso , Arginina/análogos & derivados , Arginina/sangue , Fator Natriurético Atrial/sangue , Velocidade do Fluxo Sanguíneo , Endotelina-1/sangue , Epinefrina/sangue , Agregação Eritrocítica , Feminino , Fibrinogênio/metabolismo , Mãos , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/fisiopatologia , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/fisiopatologia , Hiperlipoproteinemia Tipo II/terapia , Fluxometria por Laser-Doppler , Masculino , Angioscopia Microscópica , Pessoa de Meia-Idade , Norepinefrina/sangue , Fotopletismografia
4.
Ther Drug Monit ; 33(2): 155-64, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21383657

RESUMO

INTRODUCTION: Mycophenolic acid (MPA) plasma concentrations are highly variable on standard-dose mycophenolate mofetil therapy. At creatinine clearances below 25 mL/min, MPA clearance increases as a result of a higher nonprotein-bound fraction. Patients with delayed graft function (DGF) after renal transplantation are exposed to low total MPA concentrations, when risk of rejection is highest. This study investigated the influence of DGF on MPA exposure and on clinical outcome. METHODS: Adult renal transplantation patients treated with mycophenolate mofetil, corticosteroids, and either microemulsified cyclosporine (n = 459) or tacrolimus (n = 371) participated in a randomized controlled trial (the Fixed-Dose Concentration-Controlled [FDCC] Study). Abbreviated MPA areas under the curve (AUCs) were obtained on Day 3, Day 10, Week 4, and Month 3, to calculate MPA AUC0₋12. Free MPA AUC values were available for a subgroup of patients (n = 269). RESULTS: The overall incidence of DGF was 187 of 830 (23%) and did not differ between cyclosporine-treated (24%) and tacrolimus- (21%) treated patients. The incidence of biopsy-proven acute rejection at 12 months was significantly higher in patients with DGF (13.8% versus 21.4%). Patients with DGF had significantly lower dose-corrected MPA AUC on Day 3 and Day 10. Free MPA fraction and dose-corrected free MPA AUC were significantly higher in patients with DGF, from Day 3 until Month 3. The total number of patients with at least one opportunistic infection was significantly higher in patients with DGF (33.2%) compared with patients without DGF (25.8%) (P = 0.048). Patients with DGF developing opportunistic infections did not have higher total MPA AUC nor higher free MPA AUC compared with those without opportunistic infections. CONCLUSION: Patients with DGF have significantly lower dose-corrected MPA AUC in the first month after renal transplantation, presumably as a result of enhanced MPA clearance on account of the elevated MPA free fraction. Because patients with DGF have a higher rate of acute rejection and lower MPA exposure, higher dosing of mycophenolate mofetil in such patients may improve outcome. However, the already increased incidence of opportunistic infections in patients with DGF is a concern.


Assuntos
Função Retardada do Enxerto/metabolismo , Monitoramento de Medicamentos , Imunossupressores/farmacocinética , Transplante de Rim , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/farmacocinética , Corticosteroides/uso terapêutico , Adulto , Área Sob a Curva , Creatinina/sangue , Creatinina/metabolismo , Ciclosporina/uso terapêutico , Interações Medicamentosas , Quimioterapia Combinada , Feminino , Rejeição de Enxerto/complicações , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Masculino , Ácido Micofenólico/administração & dosagem , Ácido Micofenólico/efeitos adversos , Ácido Micofenólico/uso terapêutico , Infecções Oportunistas/complicações , Tacrolimo/uso terapêutico , Falha de Tratamento
5.
J Alzheimers Dis ; 23(4): 717-26, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21157024

RESUMO

The presence of apolipoprotein E (ApoE) ε4 allele is a risk factor for Alzheimer's disease (AD) and associated with a more pronounced reduction of amyloid-ß 1-42 (Aß1-42) in the cerebrospinal fluid (CSF). Because a decrease of Aß1-42 and increase of tau protein levels, both important biomarkers for AD, are also reported in Creutzfeldt-Jakob disease (CJD), we analyzed if a similar relationship can be observed in this rapid progressive dementia. Our study included 309 patients with sporadic CJD (147 neuropathologically confirmed and 162 probable cases). We analyzed the role of ApoE ε4 in sporadic CJD (sCJD), in particular the influence on the CSF-markers 14-3-3 protein, tau protein, neuron-specific enolase, S100 protein, Aß1-42, and Aß1-40. No differences in the ApoE ε4 allele frequency and ApoE genotype distribution between sCJD and published healthy controls were observed. The ApoE ε4 allele had no effect on disease duration or age at onset. We detected a dose-dependent ApoE ε4 effect on the decrease of Aß1-42 in sCJD. ApoE ε4 carriers with one ApoE ε4 allele showed significantly reduced Aß1-42 values (p < 0.0001) in comparison with non-carriers. ApoE ε4 allele is not a risk factor for sCJD but modifies the Aß1-42 levels in CSF in a similar manner as in AD. Based on our results in sCJD patients, we hypothesize that the ApoE ε4 effect on Aß1-42 values might not be disease-specific.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Apolipoproteína E4/genética , Síndrome de Creutzfeldt-Jakob/líquido cefalorraquidiano , Síndrome de Creutzfeldt-Jakob/genética , Fragmentos de Peptídeos/líquido cefalorraquidiano , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Biomarcadores/líquido cefalorraquidiano , Síndrome de Creutzfeldt-Jakob/diagnóstico , Feminino , Frequência do Gene/genética , Humanos , Masculino , Pessoa de Meia-Idade
6.
Ther Drug Monit ; 32(4): 405-12, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20592645

RESUMO

The aim of this study was to elucidate the role of mycophenolic acid (MPA) in cellular pathways of renal fibrosis. Different assays were applied in a renal fibroblast model using COS-7 cells: assays for cell proliferation, scratch wound closure and collagen matrix contraction, gene quantification, and Western blotting. The results indicate that MPA treatment leads to inosine monophosphate dehydrogenase (IMPDH)-dependent inhibition of fibroblast proliferation and wound closure as well as an unexpected IMPDH-independent inhibition of collagen matrix contraction. Interestingly, the IMPDH-independent expression of CTGF after 6 hours incubation with MPA was significantly decreased; however, it became significantly increased and IMPDH-dependent after 24 hours of incubation and longer. Increased mRNA level of COL1A1, TGFbeta1, and TNFalpha was observed after MPA treatment. An unanticipated finding was the divergent and late MPA effect leading to a significant increase of TGFbeta1 and CTGF gene expression. The results suggest that long-term incubation with MPA alters signals located upstream of transforming growth factor-beta. Furthermore, the protein expression of the apoptotic marker ANXA5 was analyzed in the cell line to exclude apoptosis-related effects using 0.1 to 100 micromol/L MPA. Moreover, in COL4A3-deficient mice treated with different doses of mycophenolate mofetil, we found no significant differences in the gene expression of the same genes supporting the idea of a TGFbeta-independent pathway of tubulointerstitial fibrosis in this model for progressive renal disease. In conclusion, the current study indicates that MPA displays IMPDH-dependent and IMPDH-independent effects on renal fibroblast proliferation and function as well as complex signal transduction in COS-7-cells. Alternative inhibitory pathways may contribute to antifibrotic effect of MPA.


Assuntos
Fibroblastos/efeitos dos fármacos , IMP Desidrogenase/metabolismo , Imunossupressores/farmacologia , Rim/citologia , Ácido Micofenólico/farmacologia , Animais , Autoantígenos/genética , Western Blotting , Células COS , Proliferação de Células/efeitos dos fármacos , Chlorocebus aethiops , Colágeno/metabolismo , Colágeno Tipo IV/genética , Relação Dose-Resposta a Droga , Matriz Extracelular/efeitos dos fármacos , Fibrose/induzido quimicamente , Fibrose/patologia , Expressão Gênica/efeitos dos fármacos , IMP Desidrogenase/genética , Rim/efeitos dos fármacos , Camundongos , Camundongos Knockout , Cicatrização/genética , Cicatrização/fisiologia
7.
Ther Apher Dial ; 14(2): 136-42, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20438534

RESUMO

Clinical observations revealed an increased prevalence of iron deficiency anemia without chronic bleeding in patients treated with serial low-density lipoprotein (LDL) apheresis. Since several different proteins are adsorbed by LDL apheresis beside pro-atherogenic lipoproteins, we examined the modification of the full blood count, plasma iron, vitamin B12, folic acid, and hemolysis by LDL apheresis. Nineteen patients (55 (50-59) years, 4 female, 15 male) undergoing chronic LDL apheresis due to mixed dyslipidemia (N = 17), homozygous familiar hypercholesterolemia (N = 1) or isolated elevated lipoprotein(a) (N = 1) were included in this study. They were treated with direct adsorption of lipoproteins (DALI; N = 6), heparin-induced LDL-precipitation (HELP; N = 7) or double filtration plasmapheresis (DFPP; N = 6). The patients' full blood count, iron metabolism (plasma iron, ferritin, transferrin, transferrin saturation), vitamins involved in erythropoiesis (vitamin B12 and folic acid), and markers of hemolysis (haptoglobin and free hemoglobin) were analyzed directly before and after LDL apheresis. A single LDL apheresis session significantly decreased the levels (reduction in the median [25(th)-75(th) percentiles] of: ferritin 9.8 [1.3-18] %; P = 0.004), transferrin (12.1 [10.0-15.96] %; P = 0.0005), and vitamin B12 (17.8 [16.2-20.8] %; P = 0.0005). Thereby, transferrin and vitamin B12 were decreased in all (N = 19) and ferritin in 74% (N = 14) of the patients. Twelve out of 19 patients (63.2%) had mild anemia despite iron administration in 14 out of 19 patients (73.7%). LDL apheresis had no significant influence on full blood count, plasma iron, transferrin saturation, folic acid, or hemolysis. Similar changes were observed in all LDL apheresis methods used. LDL apheresis significantly decreases ferritin, transferrin, and vitamin B12, suggesting an influence of serial LDL apheresis on erythropoiesis.


Assuntos
Anemia/etiologia , Remoção de Componentes Sanguíneos/efeitos adversos , Dislipidemias/terapia , Eritropoese , Remoção de Componentes Sanguíneos/métodos , Feminino , Ferritinas/metabolismo , Filtração , Heparina/química , Humanos , Hiperlipoproteinemia Tipo II/terapia , Lipoproteína(a)/sangue , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Plasmaferese/métodos , Transferrina/metabolismo , Vitamina B 12/metabolismo
8.
Ther Apher Dial ; 14(2): 143-52, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20438535

RESUMO

We retrospectively analyzed 10 906 lipid apheresis sessions (heparin-induced lipoprotein precipitation, direct adsorption of lipoproteins, double filtration plasmapheresis, dextran sulfate adsorption, and immunoadsorption) in 38 patients who were consecutively treated in our department during the last 20 years. The incidences of major cardiovascular events (MACE) (death, cerebrovascular accident, myocardial infarction, limb amputation, and renal vascular involvement) were taken separately as primary end-points or as a combined end-point. The time-course of secondary end-points (coronary and extracranial status of arteries, left ventricular function, occlusive artery disease, and calculated glomerular filtration rate [cGFR]) were also evaluated, as well as the extent of the reduction in plasma lipids and lipoproteins and the incidence of therapy associated side-effects. MACE decreased from 7.02% events per patient per year at the start of lipid apheresis to 1.17% during lipid apheresis and the rate of myocardial revascularization decreased from 22.8% to 3.8% per patient per year. Classical (diabetes mellitus, arterial hypertension, and smoking history), as well as novel risk factors (cGFR < 60 mL/min, statin withdrawal, mixed hyperlipoproteinemia, and elevated lipoprotein (a)) were associated with an elevated risk for MACE. All applied methods had comparable effects. All lipid apheresis methods proved to be safe and suitable for long-term treatment. The present data demonstrate that treatment with lipid apheresis is very effective and leads to long-term reduction in cardiovascular mortality and morbidity.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Doenças Cardiovasculares/prevenção & controle , Hiperlipidemias/terapia , Plasmaferese/métodos , Adulto , Remoção de Componentes Sanguíneos/efeitos adversos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Sulfato de Dextrana/química , Filtração , Seguimentos , Heparina/química , Humanos , Hiperlipidemias/complicações , Técnicas de Imunoadsorção , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Plasmaferese/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
9.
Ther Drug Monit ; 32(1): 73-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20042922

RESUMO

Within the scope of this study, the potential antifibrotic effect of mycophenolate mofetil (MMF) on COL4A3-deficient mice as an animal model for progressive renal fibrosis was investigated regarding kidney function and survival. Thirty-five animals were randomly assigned to one of five groups and treated with doses of 0, 10, 50, 100, or 150 mg/kg MMF per day, respectively. When increasing somnolence was observed, indicating end-stage renal disease, the mice were euthanized and blood was obtained. Serum concentrations of creatinine, urea nitrogen, total protein, mycophenolic acid (MPA), and mycophenolic acid glucuronide (MPAG) were quantified. The kidney histology was examined using hematoxylin and eosin as well as trichrome staining. The mean overall survival was 65.9 (+/-6.1) days with no significant difference between the treatment groups (P > 0.05, Mantel-Cox test). Serum predose concentrations of MPA and MPAG showed considerable interindividual variability. There was no correlation between survival time and MPA or MPAG concentrations (P > 0.05, Spearman rank correlation). However, an apparent decrease in serum creatinine and urea nitrogen concentrations was observed at higher doses of MMF, eg, -54% for creatinine in the 150-mg/kg/day group compared with placebo. A highly significant reciprocal correlation between MPA concentrations and serum creatinine was demonstrated (P < 0.01, r = -0.655, Spearman rank correlation). In conclusion, MMF may be a candidate drug for preserving kidney function in progressive renal fibrosis.


Assuntos
Autoantígenos/genética , Colágeno Tipo IV/genética , Imunossupressores/farmacologia , Nefropatias/tratamento farmacológico , Ácido Micofenólico/análogos & derivados , Animais , Modelos Animais de Doenças , Progressão da Doença , Relação Dose-Resposta a Droga , Fibrose , Imunossupressores/administração & dosagem , Imunossupressores/farmacocinética , Nefropatias/mortalidade , Nefropatias/patologia , Testes de Função Renal , Camundongos , Camundongos Knockout , Ácido Micofenólico/administração & dosagem , Ácido Micofenólico/farmacocinética , Ácido Micofenólico/farmacologia , Taxa de Sobrevida
10.
Clin Biochem ; 43(1-2): 208-13, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19744471

RESUMO

OBJECTIVES: The acyl glucuronide (AcMPAG) of mycophenolic acid (MPA) forms covalent protein adducts and possesses antiproliferative properties independent of IMPDH inhibition. The underlying mechanism is unknown. Disorganized tubulin polymerization prevents cell cycle progression. We investigated whether AcMPAG interacts with tubulin polymerization. DESIGN AND METHODS: AcMPAG (1.0-100 microM) was incubated with bovine tubulin in the presence of GTP. Polymerization was followed at 340 nm. The time until onset and the extent of polymerization were determined. MPA (100 microM), phenolic glucuronide MPAG (100 microM), and paclitaxel (10 microM) served as controls. RESULTS: MPAG was without effect. The AcMPAG effect on tubulin polymerization was dose dependent and significantly stronger (about 2.5-fold) than that of MPA (n=4; p<0.05), but weaker than paclitaxel. CONCLUSIONS: MPA and AcMPAG can induce tubulin polymerization in the presence of GTP with AcMPAG being significantly stronger. This property of AcMPAG may contribute to its IMPDH independent antiproliferative effect.


Assuntos
Inibidores Enzimáticos/metabolismo , Glucuronídeos/metabolismo , Ácido Micofenólico/metabolismo , Estrutura Quaternária de Proteína , Moduladores de Tubulina/metabolismo , Tubulina (Proteína) , Animais , Bovinos , Guanosina Trifosfato/metabolismo , Paclitaxel/metabolismo , Polímeros/química , Polímeros/metabolismo , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo
12.
Diabetes ; 58(12): 2873-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19720800

RESUMO

OBJECTIVE: Recent studies in humans and animal models of obesity have shown increased adipose tissue activity of 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), which amplifies local tissue glucocorticoid concentrations. The reasons for this 11beta-HSD1 dysregulation are unknown. Here, we tested whether 11beta-HSD1 expression, like the metabolic syndrome, is "programmed" by prenatal environmental events in a nonhuman primate model, the common marmoset monkey. RESEARCH DESIGN AND METHODS: We used a "fetal programming" paradigm where brief antenatal exposure to glucocorticoids leads to the metabolic syndrome in the offspring. Pregnant marmosets were given the synthetic glucocorticoid dexamethasone orally for 1 week in either early or late gestation, or they were given vehicle. Tissue 11beta-HSD1 and glucocorticoid receptor mRNA expression were examined in the offspring at 4 and 24 months of age. RESULTS: Prenatal dexamethasone administration, selectively during late gestation, resulted in early and persistent elevations in 11beta-HSD1 mRNA expression and activity in the liver, pancreas, and subcutaneous-but not visceral-fat. The increase in 11beta-HSD1 occurred before animals developed obesity or overt features of the metabolic syndrome. In contrast to rodents, in utero dexamethasone exposure did not alter glucocorticoid receptor expression in metabolic tissues in marmosets. CONCLUSIONS: These data suggest that long-term upregulation of 11beta-HSD1 in metabolically active tissues may follow prenatal "stress" hormone exposure and indicates a novel mechanism for fetal origins of adult obesity and the metabolic syndrome.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Tecido Adiposo/enzimologia , Envelhecimento , Síndrome Metabólica/enzimologia , Efeitos Tardios da Exposição Pré-Natal , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Envelhecimento/metabolismo , Animais , Glicemia/metabolismo , Callithrix , Dexametasona , Feminino , Regulação Enzimológica da Expressão Gênica , Glucocorticoides , Síndrome Metabólica/induzido quimicamente , Reação em Cadeia da Polimerase , Gravidez , Fatores de Tempo , Triglicerídeos/sangue , Regulação para Cima
13.
J Proteome Res ; 8(6): 3161-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19320461

RESUMO

Endothelial dysfunction is a common denominator of cardiovascular disease. Central to endothelial dysfunction is a decrease in the bioavailability of nitric oxide (NO) synthesized by endothelial NO synthase (NOS-3). In vivo, the level of fluid shear stress (FSS) exerted by the flowing blood determines NOS-3 expression. However, in contrast to the -786T variant of the nos-3 gene, the -786C variant is not sensitive to shear stress. Consequently, cells homozygous for this variant have an inadequate capacity to synthesize NO. Therefore, we have compared shear stress-induced protein expression in human primary cultured endothelial cells with TT or CC genotype. Cells with the CC genotype exhibited a greatly reduced FSS-induced NOS-3 expression as well as a diminished NO synthesis capacity when compared to TT genotype cells. Proteome changes in response to FSS (30 dyn/cm(2) for 24 h) were monitored by 2D-gel electrophoresis/densitometry/mass spectrometry. Of a total of 14 FSS-sensitive proteins, 8 were identically expressed in all cells. Four proteins, all of them part of the NO-dependent endoplasmic reticulum-stress response, were up-regulated by FSS only in cells with TT genotype. In contrast, CC genotype cells responded to FSS with a unique increase in manganese-containing superoxide dismutase expression. These differences in protein expression may (i) reflect the low bioavailability of NO in cells homozygous for the -786C variant of the nos-3 gene and (ii) point to a mechanism by which this deficit is counterbalanced by protecting the less abundant NO from rapid degradation.


Assuntos
Células Endoteliais/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Polimorfismo Genético , Proteoma/metabolismo , Células Cultivadas , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/metabolismo , Eletroforese em Gel Bidimensional , Perfilação da Expressão Gênica , Humanos , Espectrometria de Massas , Óxido Nítrico/genética , Óxido Nítrico/metabolismo , Proteoma/genética , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estresse Mecânico , Estresse Fisiológico , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
14.
Carcinogenesis ; 30(6): 918-26, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19321799

RESUMO

Mutations in Patched (PTCH) have been associated with tumors characteristic both for children [medulloblastoma (MB) and rhabdomyosarcoma (RMS)] and for elderly [basal cell carcinoma (BCC)]. The determinants of the variability in tumor onset and histology are unknown. We investigated the effects of the time-point and dosage of Ptch inactivation on tumor spectrum using conditional Ptch-knockout mice. Ptch heterozygosity induced prenatally resulted in the formation of RMS, which was accompanied by the silencing of the remaining wild-type Ptch allele. In contrast, RMS was observed neither after mono- nor biallelic postnatal deletion of Ptch. Postnatal biallelic deletion of Ptch led to BCC precancerous lesions of the gastrointestinal epithelium and mesenteric tumors. Hamartomatous gastrointestinal cystic tumors were induced by monoallelic, but not biallelic Ptch mutations, independently of the time-point of mutation induction. These data suggest that the expressivity of Ptch deficiency is largely determined by the time-point, the gene dose and mode of Ptch inactivation. Furthermore, they point to key differences in the tumorigenic mechanisms underlying adult and childhood tumors. The latter ones are unique among all tumors since their occurrence decreases rather than increases with age. A better understanding of mechanisms underlying this ontological restriction is of potential therapeutic value.


Assuntos
Envelhecimento/patologia , Carcinoma Basocelular/genética , Dosagem de Genes , Inativação Gênica , Receptores de Superfície Celular/fisiologia , Rabdomiossarcoma/genética , Envelhecimento/genética , Animais , Carcinoma Basocelular/patologia , Cistos/genética , Cistos/patologia , Neoplasias Gastrointestinais/embriologia , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Mutação em Linhagem Germinativa , Camundongos , Camundongos Knockout , Neoplasias Musculares/genética , Neoplasias Musculares/patologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Mutação , Receptores Patched , Receptor Patched-1 , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Receptores de Superfície Celular/genética , Rabdomiossarcoma/embriologia , Rabdomiossarcoma/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
15.
Ther Drug Monit ; 31(2): 205-10, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19307937

RESUMO

Low-dose calcineurin inhibitors (CNIs) in combination with a fixed dose (2 g/d) of mycophenolate mofetil (MMF) are a strategy to minimize exposure to cyclosporine (CSA) or tacrolimus (TAC) and thus reduce CNI-related side effects. This study compared the pharmacokinetics (PK) of mycophenolic acid (MPA) and its glucuronide metabolites in stable adult liver transplant recipients with moderately impaired renal function converted from a standard to a low-dose CNI regimen in combination with a fixed dose of MMF. Full 12-hour PK profiles of MPA, free MPA, the aryl glucuronide (MPAG), and the acyl glucuronide (AcMPAG) were obtained from 30 stable liver transplant patients on low-dose CNI (CSA, n = 12; TAC, n = 18) therapy at least 3 months after initiation of low-dose therapy. Predose CSA and TAC concentrations (quantified by liquid chromatography-tandem mass spectrometry) ranged from 17 to 35 and 1.1 to 3.7 microg/L, respectively. The PK variables for MPA, MPAG, AcMPAG, and free MPA displayed wide interindividual variability. Of note was the observation that there were no significant differences in the exposure to MPA, MPAG, and free MPA between the CSA and TAC groups. MPA area under the concentration-time curves (AUCs) ranged from 31.8 to 102.1 (median: 52.9) mg.h(-1).L(-1) in the CSA group and from 22.9 to 144.8 (median: 55.9) mg.h(-1).L(-1) in the TAC group. The AcMPAG AUC on patients under low-dose CSA therapy was higher than that observed under patients on low-dose TAC therapy, although this did not quite reach statistical significance (P = 0.057). Patients receiving CSA had a significantly higher AcMPAG Cmax but not AcMPAG AUC, suggesting that only peak CSA concentrations on a low-dose CSA regimen are sufficient to impair the biliary excretion of AcMPAG. In summary, the influence of CSA on the exposure to MPA was attenuated in stable adult liver transplant recipients on a low-dose CNI therapy in combination with a fixed dose of MMF as compared with patients on a standard CNI therapy. Dose adjustment according to drug concentration measurements is recommended to optimize dosing of MMF and to maintain adequate immunosuppression in patients converted to low-dose CNI therapy.


Assuntos
Inibidores de Calcineurina , Glucuronídeos/metabolismo , Imunossupressores/farmacocinética , Transplante de Fígado , Ácido Micofenólico/análogos & derivados , Insuficiência Renal/metabolismo , Adulto , Idoso , Área Sob a Curva , Ciclosporina/uso terapêutico , Interações Medicamentosas , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/farmacocinética , Insuficiência Renal/fisiopatologia , Tacrolimo/uso terapêutico
16.
Ther Drug Monit ; 31(2): 211-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19214148

RESUMO

The antiproliferative immunosuppressive drug mycophenolic acid (MPA) is an uncompetitive inhibitor of inosine monophosphate dehydrogenase, a key enzyme in de novo synthesis of purine nucleotides. The latter are not only required for synthesis of DNA and RNA but also are essential for the regulation of numerous cellular signaling pathways modulated by guanine nucleotide binding proteins (G proteins). We undertook an analysis of the influence of MPA on protein expression in a T-lymphoblast cell line (CCRF-CEM), which displays concentration-dependent inhibition of proliferation by MPA to obtain insight into the influence of MPA on the cellular proteome. Cells were stimulated with phorbol myristate acetate/ionomycin and incubated in the presence or absence of MPA. Two-dimensional electrophoresis and densitometric imaging revealed 11 differentially expressed protein spots (P < 0.05) on MPA treatment, 6 with increased and 5 with decreased abundance. After in-gel tryptic digestion, proteins were identified by quadrupole time-of-flight mass spectrometry. Proteins displaying increased abundance after MPA treatment included splicing factor arginine/serine-rich 2, prostaglandin E synthase 3, peptidyl-prolyl cis-trans isomerase A, and deoxyuridine 5'-triphosphate nucleotidohydrolase. Endoplasmin, proliferating cell nuclear antigen, acidic leucine-rich nuclear phosphoprotein 32 family member A, and cofilin 1 showed decreased abundance after MPA treatment. Three separate spots (1 decreased and 2 increased abundance) were identified as Rho guanosine diphosphate dissociation inhibitor 2 (Rho GDI 2) proteins. Western blotting with a monoclonal antibody directed against the Rho GDI 2 site cleaved by caspase 3 demonstrated 1 spot with increased abundance to be the caspase 3-cleaved product of Rho GDI 2 lacking the first 19 amino acids. Rho GDI 2 plays a central regulatory role in the activation of Rho guanosine triphosphatases that function as molecular switches in cell signaling pathways affecting cell cytoskeletal dynamics and motility. Our data suggest that MPA can modulate Rho GDI 2 levels in T lymphocytes, thereby potentially disrupting cell signaling pathways important for T-cell function.


Assuntos
Caspase 3/metabolismo , Inibidores de Dissociação do Nucleotídeo Guanina/metabolismo , Imunossupressores/farmacologia , Linfócitos/efeitos dos fármacos , Ácido Micofenólico/farmacologia , Proteoma/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proliferação de Células , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Linfócitos/metabolismo , Inibidor beta de Dissociação do Nucleotídeo Guanina rho , Inibidores da Dissociação do Nucleotídeo Guanina rho-Específico
17.
Ther Drug Monit ; 31(2): 139-52, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19177031

RESUMO

In 2007, a consortium of European experts on tacrolimus (TAC) met to discuss the most recent advances in the drug/dose optimization of TAC taking into account specific clinical situations and the analytical methods currently available and drew some recommendations and guidelines to help clinicians with the practical use of the drug. Pharmacokinetic, pharmacodynamic, and more recently pharmacogenetic approaches aid physicians to individualize long-term therapies as TAC demonstrates a high degree of both between- and within-individual variability, which may result in an increased risk of therapeutic failure if all patients are administered a uniform dose. TAC has undoubtedly benefited from therapeutic drug monitoring, but interpretation of the blood concentration is confounded by the relative differences between the assays. Single time points, limited sampling strategies, and area under concentration-time curve have all been considered to determine the most appropriate sampling procedure that correlates with efficacy. Therapeutic trough TAC concentration ranges have changed since the initial introduction of the drug, while still maintaining adequate immunosuppression and avoiding drug-related adverse effects. Pharmacodynamic markers have also been considered advantageous to the clinician, which may better reflect efficacy and safety, taking into account the between-individual variability rather than whole blood concentrations. The choice of method, differences between methods, and potential pitfalls of the method should all be considered when determining TAC concentrations. The recommendations of this consensus meeting regarding the analytical methods include the following: encourage the development and promote the use of analytical methods displaying a lower limit of quantification (1 ng/mL), perform careful validation when implementing a new analytical assay, participate in external proficiency testing programs, promote the use of certified material as calibrators in high-performance liquid chromatography with mass spectrometric detection methods, and take account of the assay and intermethod bias when comparing clinical trial outcomes. It is also important to consider that TAC concentrations may also be influenced by other factors such as specific pharmacokinetic characteristics associated with the population, drug interactions, pharmacogenetics, adverse events that may alter TAC concentrations, and any change in the oral formulation that may result in pharmacokinetic changes. This meeting emphasized the importance of obtaining multicenter prospective trials to assess the efficacy of alternative strategies to TAC trough concentrations whether it is other single time points or area under the concentration-time curve Bayesian estimation using limited sampling strategies and to select, standardize, and validate routine biomarkers of TAC pharmacodynamics.


Assuntos
Monitoramento de Medicamentos/métodos , Imunossupressores/farmacocinética , Imunossupressores/uso terapêutico , Transplante de Órgãos , Tacrolimo/farmacocinética , Tacrolimo/uso terapêutico , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Interações Medicamentosas , Humanos , Imunossupressores/efeitos adversos , Espectrometria de Massas , Farmacogenética , Tacrolimo/efeitos adversos
18.
Ther Drug Monit ; 31(1): 31-41, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19065122

RESUMO

The aim of the present study was to investigate whether the acyl glucuronide of mycophenolic acid (AcMPAG) directly affects gene expression independent of guanosine (G) depletion. Human native mononuclear cells from healthy volunteers were studied. A concentration of 100 micromol/L (50 mg/L) AcMPAG, which provided effective inhibition of cell proliferation according to dose-response curves, was selected for gene expression analysis on microarray, verified by quantitative real-time polymerase chain reaction on the LightCycler. Differentially regulated genes on the microarray were 114 inosine monophosphate dehydrogenase-independent genes involved in cell proliferation, signal transduction, chemokine stimulation, endocytosis, vesicle transport, cell adhesion, and cytoskeleton. For verification, 16 genes, which were directly or indirectly related to cell proliferation, were selected for quantitative real-time polymerase chain reaction. SCNM1, ANP32E, CXCL13, CALM1, DKFZp451J0118, TPM3, CDC42, YWHAE, CXCL3, RDX, NDUFA3, and SOD1 showed no significant difference between the studied groups (P > 0.05). CCL1 gene expression was significantly regulated (P < 0.05) only in the mononuclear cell group treated with AcMPAG, whereas YWHAZ gene expression was significantly regulated only in the group treated with AcMPAG in presence of G and 8-aminoguanosine. The difference of interleukin 2 (IL2) and nucleobindin 1 (NUCB1) expression was significant between control and AcMPAG (P < 0.05) however not significant between AcMPAG in presence and absence of G and 8-aminoguanosine (P > 0.05). The expression of interleukin 2 and nucleobindin 1 revealed an effect of AcMPAG on gene expression independent of inosine monophosphate dehydrogenase inhibition.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Proteínas de Ligação ao Cálcio/biossíntese , Proteínas de Ligação a DNA/biossíntese , Inibidores Enzimáticos/farmacologia , IMP Desidrogenase/antagonistas & inibidores , Interleucina-2/biossíntese , Monócitos/metabolismo , Ácido Micofenólico/farmacologia , Adulto , Proliferação de Células/efeitos dos fármacos , Feminino , Expressão Gênica/efeitos dos fármacos , Glucuronídeos/farmacologia , Guanosina/farmacologia , Humanos , Masculino , Monócitos/efeitos dos fármacos , Proteínas do Tecido Nervoso , Nucleobindinas , Análise de Sequência com Séries de Oligonucleotídeos , RNA/biossíntese , RNA/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Neurobiol Aging ; 30(4): 615-21, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17822808

RESUMO

OBJECTIVE: To analyze whether a positive family history of dementia (PFHD) is more common in sporadic CJD (sCJD) than in healthy/population controls and to study associated risk factors. PATIENTS/METHODS: Six hundred and eighty-five sCJD patients and 659 sex-/age-matched controls were included. A PFHD in parents/grandparents/siblings was evaluated. The PRNP M129V polymorphism and ApoE genotype in sCJD with/without PFHD were determined by PCR. RESULTS: PFHD was found in 12.1% of sCJD patients and 5.6% of controls (p<0.001). No significant difference in M129V polymorphism was found between sCJD with and without PFHD. Thirty-six percent of sCJD patients with PFHD, 26% without PFHD and 19% of healthy controls had at least one ApoE4 allele. Compared to controls, ApoE4 allele frequency (p=0.005) and proportion of ApoE4 allele carriers (p=0.019) were significantly higher in sCJD with PFHD. INTERPRETATION: A higher frequency of the ApoE4 allele in sCJD with a PFHD could be indicative of an additional risk factor in CJD.


Assuntos
Apolipoproteína E4/genética , Síndrome de Creutzfeldt-Jakob/epidemiologia , Síndrome de Creutzfeldt-Jakob/genética , Predisposição Genética para Doença/genética , Polimorfismo Genético/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Química Encefálica/genética , Análise Mutacional de DNA , Saúde da Família , Feminino , Frequência do Gene/genética , Marcadores Genéticos/genética , Testes Genéticos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
20.
Ther Drug Monit ; 30(5): 570-5, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18758392

RESUMO

Data on exposure to mycophenolic acid (MPA), the active moiety of mycophenolate mofetil (MMF), in pediatric renal transplant recipients beyond the first year posttransplant are scarce. The authors therefore analyzed the long-term pharmacokinetics of MPA in 25 pediatric patients treated with 600 mg MMF/m body surface area twice a day in conjunction with cyclosporine A and prednisone. Plasma samples for 12-hour pharmacokinetic profiles were collected on day 7, and after 3, 9, 24, and 36 months posttransplant. Both the actual and the dose-normalized MPA-area under the concentration-time curve (AUC0-12) increased approximately 2-fold between day 7 and month 9 but stabilized thereafter. Both the actual and the dose-normalized MPA-AUC0-12 at months 24 and 36 were comparable to that at month 9. Presuming a therapeutic window of 30-60 mg h/L, 15 (60%) of 25 patients at day 7 had an MPA-AUC0-12 <30 mg h/L, indicating potential underexposure, whereas the proportion of patients with an MPA-AUC0-12 <30 mg h/L between months 3 and 36 was low (5%-17%). These data suggest that the recommended MMF dose of 600 mg/m body surface area twice a day in conjunction with cyclosporine A leads to MPA underexposure early posttransplant in a significant subset of patients, indicating a need for a higher initial MMF dose. Dose-normalized MPA exposure increases in the first 9 months posttransplant, consistent with a reduced MPA metabolism and increased enterohepatic recycling of MPA.


Assuntos
Transplante de Rim/fisiologia , Ácido Micofenólico/farmacocinética , Transplante/fisiologia , Administração Oral , Adolescente , Criança , Pré-Escolar , Esquema de Medicação , Feminino , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/normas , Lactente , Internacionalidade , Estudos Longitudinais , Masculino , Ácido Micofenólico/administração & dosagem , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/normas , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
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