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1.
Hepatology ; 60(6): 1826-37, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24811404

RESUMO

UNLABELLED: Understanding hepatitis C virus (HCV) replication has been limited by access to serial samples of liver, the primary site of viral replication. Our understanding of how HCV replicates and develops drug-resistant variants in the liver is limited. We studied 15 patients chronically infected with genotype 1 HCV treated with telaprevir (TVR)/pegylated-interferon alpha/ribavirin. Hepatic fine needle aspiration was performed before treatment and at hour 10, days 4 and 15, and week 8 after initiation of antiviral therapy. We measured viral kinetics, resistance patterns, TVR concentrations, and host transcription profiles. All patients completed all protocol-defined procedures that were generally well tolerated. First-phase HCV decline (baseline/treatment day 4) was significantly slower in liver than in plasma (slope plasma: -0.29; liver, -0.009; P < 0.001), whereas second-phase decline (posttreatment days 4-15) did not differ between the two body compartments (-0.11 and -0.15, respectively; P = 0.1). TVR-resistant variants were detected in plasma, but not in liver (where only wild-type virus was detected). Based upon nonstructural protein 3 sequence analysis, no compartmentalization of viral populations was observed between plasma and liver compartments. Gene expression profiling revealed strong tissue-specific expression signatures. Human intrahepatic TVR concentration, measured for the first time, was lower, compared to plasma, on a gram per milliliter basis. We found moderate heterogeneity between HCV RNA levels from different intrahepatic sites, indicating differences in hepatic microenvironments. CONCLUSION: These data support an integrated model for HCV replication wherein the host hepatic milieu and innate immunity control the level of viral replication, and the early antiviral response observed in the plasma is predominantly driven by inhibition of hepatic high-level HCV replication sites.


Assuntos
Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Fígado/virologia , Oligopeptídeos/farmacocinética , RNA Viral/sangue , Adolescente , Adulto , Idoso , Biópsia por Agulha Fina , Farmacorresistência Viral , Feminino , Expressão Gênica , Hepacivirus/genética , Hepatite C Crônica/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Oligopeptídeos/uso terapêutico , Filogenia , Resultado do Tratamento , Adulto Jovem
2.
Cureus ; 16(1): e52797, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38389629

RESUMO

This case report aims to delineate the clinical outcomes and technical considerations of hemi-hamate arthroplasty in the reconstruction of a delayed proximal interphalangeal (PIP) joint fracture-dislocation. It underscores the procedure's viability as a reconstructive option for complex finger injuries with delayed presentation. A 23-year-old male presented six weeks post-injury with a PIP joint fracture-dislocation of the left index finger. Traditional management options were limited due to the delayed presentation and the nature of the injury. A surgical intervention was performed using an autologous osteochondral hemi-hamate graft to reconstruct the articular surface. Herein, we describe the detailed surgical steps, postoperative care, and rehabilitation protocols. Over a five-month follow-up period, the patient demonstrated significant functional improvement. The range of motion in the PIP joint increased substantially, with a notable reduction in pain levels. Radiographic assessments showed successful graft incorporation and joint alignment. The patient reported satisfaction with the aesthetic and functional outcome, highlighting an enhanced quality of life post-surgery. Hemi-hamate arthroplasty emerges as a favorable surgical option for delayed PIP joint fracture-dislocations, offering improved articular congruity, joint stability, and functional outcomes. This case contributes to the growing body of evidence supporting the procedure's effectiveness and underscores the importance of considering innovative approaches in complex hand injuries.

3.
Clin Pharmacol Drug Dev ; 11(4): 475-485, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35172045

RESUMO

Vadadustat is a hypoxia-inducible factor prolyl-hydroxylase inhibitor being developed for the treatment of anemia in patients with chronic kidney disease. Sequelae of chronic kidney disease include hyperphosphatemia and anemia, which are frequently treated with phosphate binders and iron supplements, respectively. Two studies evaluating the pharmacokinetics, safety, and tolerability of a single oral dose of vadadustat coadministered with a phosphate binder or iron supplement were conducted in healthy adult participants. In study 1, 54 healthy women and men were administered vadadustat (300 mg) alone and 1 hour before, concurrently with, or 2 hours after a phosphate binder (sevelamer carbonate 1600 mg, calcium acetate 1334 mg, or ferric citrate 2000 mg). In study 2, 10 healthy men were administered vadadustat (450 mg) alone and concomitantly with the oral iron supplement ferrous sulfate (325 mg [equivalent to 65 mg of elemental iron]). Vadadustat exposure was reduced by coadministration with sevelamer carbonate, calcium acetate, ferric citrate, or ferrous sulfate. Geometric least squares mean ratios for area under the concentration-time curve from time 0 to infinity were reduced 37% to 55% by phosphate binders and 46% by ferrous sulfate. However, when vadadustat was administered 1 hour before phosphate binders, 90% confidence intervals for vadadustat exposure were within the no-effect boundaries of +50% to -33%, indicating that drug-drug interactions can be reduced by administering vadadustat 1 hour before phosphate binders. Vadadustat was well tolerated when administered in conjunction with phosphate binders or an iron supplement.


Assuntos
Ferro da Dieta , Ferro , Adulto , Feminino , Glicina/análogos & derivados , Humanos , Masculino , Fosfatos , Ácidos Picolínicos
4.
Clin Pharmacol Drug Dev ; 10(8): 950-958, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33661566

RESUMO

Vadadustat is a hypoxia-inducible factor prolyl hydroxylase inhibitor in development for the treatment of anemia of chronic kidney disease. This phase 1, open-label, parallel-group, single-dose study evaluated the pharmacokinetics of 450-mg vadadustat in adults with moderate hepatic impairment (Child-Pugh class B) vs those with normal hepatic function. Primary end points were area under the plasma concentration-time curve (AUC) from dosing to last concentration and to infinity, as well as maximum concentration (Cmax ); additional pharmacokinetic parameters included time to Cmax (Tmax ) and half-life. Safety and tolerability were also assessed. All enrolled participants (n = 16) completed the study. Demographics were similar in both groups (overall, 100% White; 62.5% female; mean age, 59.2 years). Vadadustat plasma exposure was higher in the moderate hepatic impairment group, whereas maximum concentration was similar between groups. Point estimates of the hepatic impairment : normal geometric mean ratios (90% confidence interval) for AUC from dosing to last concentration, AUC from dosing to infinity, and Cmax were 1.05 (0.82-1.35), 1.06 (0.82-1.36), and 1.02 (0.79-1.32), respectively. Mean elimination half-life was 5.8 and 7.8 hours in the normal and hepatic impairment groups, respectively. Treatment-emergent adverse events were mostly mild in severity, and vadadustat was generally well tolerated. In conclusion, moderate hepatic impairment did not significantly impact vadadustat systemic exposure, and mild hepatic impairment is unlikely to alter vadadustat exposure.


Assuntos
Jejum/sangue , Glicina/análogos & derivados , Hepatopatias/fisiopatologia , Ácidos Picolínicos/administração & dosagem , Inibidores de Prolil-Hidrolase/administração & dosagem , Administração Oral , Idoso , Área Sob a Curva , Feminino , Glicina/administração & dosagem , Glicina/efeitos adversos , Glicina/farmacocinética , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Picolínicos/efeitos adversos , Ácidos Picolínicos/farmacocinética , Inibidores de Prolil-Hidrolase/efeitos adversos , Inibidores de Prolil-Hidrolase/farmacocinética
5.
Eur J Pharm Biopharm ; 70(1): 51-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18583114

RESUMO

Two poorly soluble, potent anti-cancer drugs, paclitaxel and camptothecin, were successfully solubilized by mixed micelles of polyethylene glycol-phosphatidyl ethanolamine (PEG-PE) and vitamin E. Drug-containing micelles were additionally modified with anti-nucleosome monoclonal antibody 2C5 (mAb 2C5), which can specifically bring micelles to tumor cells in vitro. The optimized micelles had an average size of about 13-22 nm and the immuno-modification of micelles did not significantly change it. The solubilization of both drugs by the mixed micelles was more efficient than by micelles made of PEG-PE alone. Solubilization of camptothecin in micelles prevented also the hydrolysis of active lactone form of the drug to inactive carboxylate form. Drug-loaded mixed micelles and mAb 2C5-immunomicelles demonstrated significantly higher in vitro cytotoxicity than free drug against various cancer cell lines.


Assuntos
Anticorpos Monoclonais/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Camptotecina/farmacologia , Portadores de Fármacos , Micelas , Paclitaxel/farmacologia , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Vitamina E/química , Animais , Anticorpos Monoclonais/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Camptotecina/química , Camptotecina/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Hidrólise , Camundongos , Nucleossomos/imunologia , Paclitaxel/química , Paclitaxel/metabolismo , Tamanho da Partícula , Solubilidade , Tecnologia Farmacêutica/métodos , Fatores de Tempo
6.
Int J Pharm ; 315(1-2): 148-57, 2006 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-16616818

RESUMO

Mixed micelles prepared of poly(ethylene glycol)2000-phosphatidyl ethanolamine conjugate (PEG(2000)-PE) and d-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) in 1:1 molar ratio have been investigated. Micelle formation was confirmed by NMR spectroscopy. CMC of the micelles was found to be 1.5 x 10(-5)M. Poorly soluble anti-cancer drug paclitaxel (PCL) was efficiently solubilized in 15 nm non-toxic PEG-PE/TPGS micelles. PCL entrapment was quite stable with only about 20% of the incorporated drug released from micelles after 48 h at 37 degrees C. In addition, PCL-containing PEG(2000)-PE/TPGS micelles were stable in vitro under various conditions modeling the physiological ones, in particular, at low pH values and in the presence of bile acids, which is especially important for their possible oral administration. Fluorescently labeled micelles demonstrated time-dependent internalization by human colon adenocarcinoma cell line, Caco-2. The internalization of PEG(2000)-PE/TPGS micelles loaded with P-glycoprotein (P-gp) substrate, rhodamine-123 (RH-123), opposite to the internalization of the free RH-123, was not influenced by the inhibition of the P-gp pump with verapamil hydrochloride, which assumes a P-gp-independent micelle internalization.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Micelas , Paclitaxel/administração & dosagem , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Ácidos e Sais Biliares , Células CACO-2 , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Humanos , Concentração de Íons de Hidrogênio , Paclitaxel/farmacocinética , Fosfatidiletanolaminas , Polietilenoglicóis , Solubilidade
7.
J Control Release ; 128(3): 255-60, 2008 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-18479772

RESUMO

Stable nanocolloids of insoluble drugs with very high drug content (up to 90% wt) can be easily and reproducibly prepared through the application of the layer-by-layer (LbL) technology, alternate adsorption of oppositely charged polyelectrolytes on the surface of drug nanoparticles produced by ultrasonication of larger drug crystals. Such polymeric coating prevents drug nanoparticle aggregation and creates a firm polymeric shell on their surface. Drug release rate from such nanocolloidal particles can be easily controlled by assembling multilayer shells with variable shell density and thickness. Various additional functions, such as specific targeting ligands, can be easily attached to the surface on nanocolloidal particles of poorly soluble drugs by using a polymer with free reactive groups for the "outer" coating. This may represent a novel approach to preparing convenient dosage forms of poorly soluble drugs.


Assuntos
Antineoplásicos/química , Coloides , Nanopartículas , Paclitaxel/química , Sonicação , Tamoxifeno/química , Tecnologia Farmacêutica/métodos , Adsorção , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Composição de Medicamentos , Estabilidade de Medicamentos , Humanos , Cinética , Tamanho da Partícula , Solubilidade , Propriedades de Superfície
8.
J Drug Target ; 16(7): 601-4, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18686131

RESUMO

Long-circulating liposomes loaded with doxorubicin (Dox) were additionally modified with the prostate cell-specific monoclonal antibody 5D4 (mAb 5D4). The resultant Dox-loaded 5D4-immunoliposomes specifically recognized prostate cancer cell lines of several different types expressing the mAb 5D4 antigen, PSMA, and significantly enhanced cytotoxicity toward these cells compared with the non-targeted Dox-liposomes in vitro while no increased toxicity was observed toward non-prostate (lung) cancer cell line.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Lipossomos , Neoplasias da Próstata/imunologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico , Humanos , Masculino , Tamanho da Partícula
9.
J Drug Target ; 16(7): 596-600, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18686130

RESUMO

Surface architecture of pharmaceutical nanocarriers (using polymeric micelles as an example) and the length of the spacer group through which specific ligand is attached to the carrier surface determine the interaction of ligand-bearing nanocarrier with cells. We have prepared surface-modified polyethyleneglycol-phosphatidylethanolamine (PEG-PE) micelles containing TATp attached to PEG-PE with a PEG block longer or shorter (TATp-PEG(1000)-PE or TATp-PEG(3400)-PE) than the PEG block in the main micelle-forming material (PEG(750)-PE and/or PEG(2000)-PE). The length of the PEG spacer in TATp-PEG-PE should allow for a non-hindered interaction of TATp with the cell surface, but it should not be too long to allow for the conformational "folding in" of TATp moiety inside the PEG globule making it unable to interact with the cells. The "folding in" of the ligand attached to an unnecessary long PEG spacer was further supported by the fluorescence resonance energy transfer (FRET) study between fluorescently labeled lipid 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-(7-nitro-2-1,3-benzoxadiazol-4-yl) (NBD-PE) inserted into the core of PEG(750)-PE micelles and micelle-incorporated rhodamine-labeled TATp-PEG-PE. Micelles containing rhodamine-labeled TATp-PEG-PE with the longest PEG spacer (3400 Da) demonstrated strongly enhanced quenching of NBD-PE fluorescence with rhodamine-TATp confirming the "folding in" of TATp moiety into PEG globule bringing it closer to the micelle core-incorporated NBD.


Assuntos
Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Nanopartículas , Transferência Ressonante de Energia de Fluorescência , Ligantes , Micelas
10.
J Liposome Res ; 16(1): 45-55, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16556549

RESUMO

Liposome loading with Gd via the membrane-incorporated polychelating amphiphilic polymers (PAPs) significantly increases the Gd content and relaxivity (T1 parameter) of PEGylated liposomes, which can be used as contrast agents for magnetic resonance imaging (MRI). Here, we demonstrate that such Gd-containing liposomes can be additionally modified with the monoclonal anticancer antibody 2C5 (mAb 2C5) possessing the nucleosome(NS)-restricted specificity via the PEG spacer. Liposome-bound antibody preserves its specific activity (ELISA) and such Gd-loaded PEGylated 2C5-immunoliposomes specifically recognize various cancer cells in vitro and target an increased amount of Gd to their surface compared to antibody-free Gd-liposomes or Gd-liposomes modified with tumor nonspecific antibody. Gd-loaded cancer cell-targeted immunoliposomes may represent promising agents for enhanced tumor MRI.


Assuntos
Quelantes/química , Gadolínio/química , Lipossomos , Neoplasias/diagnóstico , Polímeros/química , Anticorpos Monoclonais/imunologia , Meios de Contraste , Ensaio de Imunoadsorção Enzimática , Imageamento por Ressonância Magnética , Neoplasias/patologia
11.
J Biomater Sci Polym Ed ; 15(5): 621-30, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15264663

RESUMO

Dextran-polyethylene glycol (PEG) conjugates were synthesized by activating dextran hydroxy groups with carbonyldiimidazole, introducing amino groups by attaching ethylenediamine, and reacting amino groups with a succinimidyl-activated derivative of PEG. Conjugates with an average of 12 and 21 PEG (5 kDa) residues per single dextran (73 kDa) molecule were prepared. These conjugates have circulation half-lives of 5.3 h and 7.0 h, respectively, compared to 4.0 h for non-PEGylated dextran. The modification of dextran with PEG inhibits the uptake of polymer by the major organ of the reticuloendothelial system, the liver. Dextran-PEG conjugates may represent a convenient platform for long-circulating pharmaceutical preparations.


Assuntos
Dextranos/química , Portadores de Fármacos/síntese química , Polietilenoglicóis/química , Polímeros/síntese química , Animais , Dextranos/sangue , Portadores de Fármacos/farmacocinética , Feminino , Meia-Vida , Camundongos , Camundongos Endogâmicos C57BL , Polietilenoglicóis/farmacocinética , Polímeros/farmacocinética , Distribuição Tecidual
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