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1.
Eur Rev Med Pharmacol Sci ; 26(20): 7506-7513, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36314321

RESUMO

OBJECTIVE: Painful crises represents a predominant complication of sickle cell disease (SCD). The only approved treatments for painful crises in many countries are hydroxyurea plus potent analgesics. Our earlier clinical trial concluded that omega-3 and vitamin D had a potential therapeutic impact on painful crises. However, there is limited research evaluating their therapeutic applications and cost-effectiveness. This paper aims at comparing the cost-effectiveness of omega-3 and vitamin D supplementation to the standard therapy in treating painful crises among children with SCD. PATIENTS AND METHODS: Cost-effectiveness analyses of daily supplementation of omega-3 and vitamin D were performed. The economic evaluation was based on data derived from a prospective 10-month randomized clinical trial (n = 165 patients; 15 patients dropped). 50 patients were recruited into the omega-3 + standard therapy group (hydroxyurea and folic acid daily with ibuprofen as needed), 50 patients into the vitamin D + standard therapy group, and 50 patients receiving standard therapy alone served as a control group. Outcome measures from the randomized clinical trial were used to determine incremental effectiveness. Cost estimates were calculated from the healthcare payer's perspective. The analysis considered the improvement in various outcome measures and are presented here as percent change from baseline to determine the incremental effectiveness and the incremental cost for the treatment of both interventions. RESULTS: Adding omega-3 or vitamin D to the standard therapy was more cost-effective than standard treatment alone. Vitamin D was a cheaper but less cost-effective alternative for most outcomes between the two treatments, including LDL-C and HDL-C. It was also more cost-effective but less clinically effective in reducing vaso-occlusive crisis episodes and pain severity. Omega-3 supplementation was significantly more cost-effective than vitamin D supplementation and the standard treatment for those measures. CONCLUSIONS: The present study showed that using vitamin D and omega-3 as add-on treatments for a painful crisis in pediatric sickle cell disease could have overall cost-saving and clinical benefits. However, further studies with a longer treatment duration are needed to establish more significant effects of the interventions for better policy and clinical decision-making.


Assuntos
Anemia Falciforme , Ácidos Graxos Ômega-3 , Criança , Humanos , Hidroxiureia/uso terapêutico , Análise Custo-Benefício , Estudos Prospectivos , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Dor/tratamento farmacológico , Vitamina D/uso terapêutico , Ácidos Graxos Ômega-3/uso terapêutico , Suplementos Nutricionais
2.
Eur Rev Med Pharmacol Sci ; 26(14): 5043-5052, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35916800

RESUMO

OBJECTIVE: Sickle Cell Anemia (SCA), also called the Sickle Cell Disease (SCD), is an inherited hematological disorder characterized by a syndrome of acute anemia and a painful crisis. The sickling hemoglobin, Hgb-S causes viscosity and inflammation of blood vessels. Eventually, the red blood cells get eliminated from the circulation process, which leads to hemolytic anemia. This study examined the comparative effectiveness of supplementation of Omega-3 or vitamin-D to standard therapy (hydroxyurea + Ibuprofen) used for prevention and treatment of pain crises in pediatric patients living with SCD. PATIENTS AND METHODS: 165 patients participated in this randomized, double-blind, standard therapy-controlled, parallel-design trial. The patients were randomly divided into three groups, receiving three capsules of either 1,000 mg Omega-3 fish oil (400 mg EPA and 300 mg DHA) or 1.5 mL vitamin-D (2,800 IU/7 ml) daily for 10 months plus the standard therapy. Lactate dehydrogenase, high-density lipoprotein (HDL), low-density lipoprotein (LDL), hematocrit, reticulocyte count, and white-blood-cell count were determined at baseline (month zero) and end of the 10th month. The pain severity was measured using the visual analog scale method (VAS). Therefore, a 10-cm ruler with a VAS design was used to determine the patient pain intensity. The baseline time point was defined as the time spot before starting to deliver the experimental medication to the patients (month zero). At that time, the biodata of the patient on the frequency of pain episodes and the rest of the variables were collected, and the baseline data were one-year retrospective data. RESULTS: Of 165 patients enrolled in the trial, 150 were included in the final analysis. At the end of the study, there was a significant increase in serum LDL and HDL in the Omega-3 group as compared with the control group (mean of 82 mg/dL vs. 57 mg/dL; p < 0.01 and mean of 47 mg/dL vs. 43 mg/dL; p < 0.028, respectively). Other laboratory parameters were significantly influenced. The number of painful crises and pain levels was significantly decreased in the Omega-3 group compared with the control group (mean of one-episode vs. mean of three episodes; p = 0.01, mean of three on pain scale vs. six on pain scale; p = 0.018). CONCLUSIONS: Results showed that Omega-3 was more effective than vitamin-D or standard treatment alone relative to pain crises and most of the other studied items. Vitamin-D was more effective than standard therapy alone. Clinicians should consider the addition of Omega-3 supplements to the standard therapy and a de-escalation dose plan for the hydroxyurea medication.


Assuntos
Anemia Falciforme , Ácidos Graxos Ômega-3 , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Método Duplo-Cego , Ácidos Graxos Ômega-3/uso terapêutico , Humanos , Hidroxiureia/uso terapêutico , Dor/tratamento farmacológico , Estudos Retrospectivos , Vitamina D , Vitaminas/uso terapêutico
3.
J Thromb Haemost ; 16(9): 1722-1731, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29908043

RESUMO

Essentials Tissue factor pathway inhibitor (TFPI) is an antagonist of FXa and the TF-FVIIa complex. PF-06741086 is an IgG1 monoclonal antibody that targets the Kunitz-2 domain of TFPI. Single doses of PF-06741086 were evaluated in a phase 1 study in healthy volunteers. Data from this study support further investigation of PF-06741086 in individuals with hemophilia. SUMMARY: Background Tissue factor pathway inhibitor (TFPI) is a protease inhibitor of the tissue factor-activated factor VII complex and activated FX. PF-06741086 is a mAb that targets TFPI to increase clotting activity. Objectives This study was a randomized, double-blind, sponsor-open, placebo-controlled, single intravenous or subcutaneous dose escalation study to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of PF-06741086. Patients/Methods Volunteers who provided written informed consent were assigned to cohorts with escalating dose levels. Safety endpoints included treatment-emergent adverse events (TEAEs), infusion/injection site reactions, vital signs, electrocardiogram, and coagulation and hematology laboratory parameters. Pharmacokinetic (PK) and pharmacodynamic (PD) endpoints included exposures of PF-06741086 in plasma and measures of PF-06741086 pharmacology, respectively. Results Forty-one male volunteers were recruited overall. Thirty-two were dosed with PF-06741086 from 30 mg subcutaneously to 440 mg intravenously. All doses were safe and well tolerated. TEAEs were mild or moderate in severity, laboratory abnormalities were transient, there were no serious adverse events, there were no infusion/injection site reactions, and no dose escalation stopping criteria were met. Plasma exposures of PF-06741086 increased greater than proportionally with dose under the same dosing route. Coagulation pharmacology was demonstrated via total TFPI, dilute prothrombin time, D-dimer, prothrombin fragment 1 + 2 and thrombin generation assay parameters. Conclusions Single doses of PF-06741086 at multiple dose levels were safe and well tolerated in a healthy adult male population. The safety, PK and PD data from this study support progression to a multiple-dose study in hemophilic patients.


Assuntos
Anticorpos Monoclonais Humanizados , Hemostáticos/administração & dosagem , Lipoproteínas/antagonistas & inibidores , Adolescente , Adulto , Anticorpos Anti-Idiotípicos/sangue , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Neutralizantes/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Fadiga/induzido quimicamente , Meia-Vida , Hemodinâmica/efeitos dos fármacos , Hemostáticos/efeitos adversos , Hemostáticos/sangue , Hemostáticos/farmacologia , Humanos , Injeções Intravenosas , Injeções Subcutâneas , Lipoproteínas/sangue , Lipoproteínas/imunologia , Masculino , Pessoa de Meia-Idade , Dor/induzido quimicamente , Adulto Jovem
4.
J Photochem Photobiol B ; 179: 167-174, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29413990

RESUMO

BACKGROUND: Exposure of skin to simulated sunlight irradiation (SSI) has being extensively researched and shown to be the main cause for changes in the skin including changes in cellular function and generation of reactive oxygen species (ROS). This oxidative stress can subsequently exert downstream effects and the subcellular compartments most affected by this oxidative stress are mitochondria. The importance of functional mitochondrial morphology is apparent as morphological defects are related to many human diseases including diabetes mellitus, liver disease, neurodegenerative diseases, aging and cancer. OBJECTIVE: The main objective of this study was to evaluate solar radiation-induced changes in mitochondrial gene expression in human skin cells using a Q-Sun solar simulator to deliver a close match to the intensity of summer sunlight. METHODS: Spontaneously immortalised human skin epidermal keratinocytes (HaCaT) and Human Dermal Fibroblasts (HDFn) were divided into two groups. Group A were irradiated once and Group B twice 7days apart; following irradiation, mitochondrial gene expression was evaluated 1, 4 and 7days post primary exposure for group A and 1, 4, 7 and 14days post-secondary exposure for group B. RESULTS: Both the epidermal and dermal cells displayed significant reduced expression of the genes analysed for mitochondrial morphology and function; however, epidermal cells displayed this reduction post SSI earlier then dermal cells at multiple time points. CONCLUSION: The data presented here reinforces the fact that epidermal cells, while displaying a heightened sensitivity to sunlight, are less prone to changes in gene expression, while dermal cells, which appear to be more resilient are possibly more prone to genomic instability and mitochondrial damage.


Assuntos
Expressão Gênica/efeitos da radiação , Mitocôndrias/genética , Luz Solar , ATPases Associadas a Diversas Atividades Celulares/genética , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Linhagem Celular , Derme/citologia , Células Epidérmicas , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Metaloendopeptidases/genética , Metaloendopeptidases/metabolismo , Mitocôndrias/efeitos da radiação , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
5.
J Gastrointest Surg ; 21(7): 1153-1158, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28386670

RESUMO

Small cohort studies demonstrated better oncologic outcomes for patients with pathologic complete response (PathCR) after neoadjuvant treatment for locally advanced rectal cancer. This study reviews long-term outcomes of a large cohort of clinically stage II/III rectal cancer patients who received neoadjuvant chemoradiation and surgery. This is a retrospective analysis of a single-center cohort, including all clinical stage II/III rectal cancer patients who received neoadjuvant chemoradiation and surgery between 2004 and 2014 (n = 271). Cox regressions were done to assess the influence of PathCR on recurrence-free survival (RFS) and overall survival (OS), adjusting for postoperative chemotherapy, clinical AJCC staging, comorbidity, and age where appropriate. PathCR patients had significantly lower distant recurrence rates (4 vs. 15.8%; P = 0.028) and lower disease-specific mortality rates (0 vs. 8.1%; P = 0.052), compared to patients with residual disease. PathCR was associated with longer RFS (HR, 5.6 [95% CI 1.3-23.1] P = 0.018) and longer OS (HR, 3.4 [1.31-10.0] P = 0.014) compared to having pathological residual disease. This large single-center study shows that patients with PathCR have significant longer RFS and OS than patients with residual disease on pathology after neoadjuvant chemoradiation.


Assuntos
Quimiorradioterapia , Terapia Neoadjuvante , Neoplasia Residual/terapia , Neoplasias Retais/terapia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasia Residual/mortalidade , Neoplasia Residual/patologia , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Estudos Retrospectivos , Taxa de Sobrevida
6.
J Photochem Photobiol B ; 165: 298-304, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27838483

RESUMO

BACKGROUND: Sunlight represents the primary threat to mitochondrial integrity in skin given the unique nature of the mitochondrial genome and its proximity to the electron transport chain. The accumulation of mitochondrial DNA (mtDNA) mutations is a key factor in many human pathologies and this is linked to key roles of mitochondrial function in terms of energy production and cell regulation. OBJECTIVE: The main objective of this study was to evaluate solar radiation induced changes in mitochondrial integrity, function and dynamics in human skin cells using a Q-Sun solar simulator to deliver a close match to the intensity of summer sunlight. METHODS: Spontaneously immortalised human skin epidermal keratinocytes (HaCaT) and Human Dermal Fibroblasts (HDFn) were divided into two groups. Group A were irradiated once and Group B twice 7days apart and evaluated using cell survival, viability and mitochondrial membrane potential (MMP) and mass at 1, 4 and 7days post one exposure for Group A and 1, 4, 7 and 14days post second exposure for Group B. RESULTS: Viability and survival of HaCaT and HDFn cells decreased after repeat exposure to Simulated Sunlight Irradiation (SSI) with no recovery. HDFn cells showed no loss in MMP after one or two exposures to SSI compared to HaCaT cells which showed a periodic loss of MMP after one exposure with a repeat exposure causing a dramatic decrease from which cells did not recover. Mitochondrial Mass in exposed HDFn cells was consistent with control after one or two exposures to SSI; however mitochondrial mass was significantly decreased in HaCaT cells. CONCLUSION: Data presented here suggests that mitochondria in epidermal cells are more sensitive to sunlight damage compared to mitochondria in dermal cells, despite their origin, confirming a skin layer specific sensitivity to sunlight, but not as expected.


Assuntos
Mitocôndrias/efeitos da radiação , Pele/efeitos da radiação , Luz Solar , Humanos , Potencial da Membrana Mitocondrial/efeitos da radiação , Mitocôndrias/metabolismo , Pele/citologia
7.
J Thromb Haemost ; 14(2): 356-65, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26581031

RESUMO

UNLABELLED: ESSENTIALS: Antithrombin III (AT)ß binds heparin with higher affinity than ATα. A conformation-specific antibody against ATß, TPP2009, was made to investigate ATß in hemostasis. TPP2009 bound specifically to heparin-ATß and greatly reduced the anticoagulant effect of AT. This antibody was effective in elucidating the importance of ATß in hemostasis. BACKGROUND: Antithrombin III (AT)ß is an isoform of AT that lacks the post-translational carbohydrate modification at Asn135. This isoform binds heparin with greater affinity than ATα, and has been shown to target antithrombotic function to the extracellular vascular endothelial injury site. OBJECTIVES: To characterize a conformation-specific antibody against ATß and begin to investigate the role of ATß in maintaining hemostasis. METHODS: Surface plasmon resonance (SPR), antigen binding and functional assays were conducted to characterize the mode of action of antibodies generated against heparin-bound ATß (ATß*H) by the use of phage display. RESULTS: SPR and binding studies showed that one of the antibodies, TPP2009, bound specifically to ATß*H and glycosaminoglycan-associated ATß on endothelial cells. In diluted prothrombin and activated factor X (FXa)-induced clotting assays, TPP2009 dose-dependently reduced the anticoagulant effect of heparin in non-hemophilic and FVIII-deficient human plasma, with half-maximal effective concentrations (EC50 ) of 10.5 nm and 4.7 nm, respectively. In AT-deficient human plasma, TPP2009 dose-dependently inhibited the effects of exogenously added ATß and heparin. In purified systems with ATß and pentasaccharide, TPP2009 restored > 91% of FXa activity. TPP2009 dose-dependently reversed the effects of heparin in rabbit (EC50 , 25.7 nm) and cynomolgus monkey (EC50 , 21.5 nm) plasma, but not in mouse plasma. TPP2009 was also effective in partially restoring FXa activity in rabbit and cynomolgus monkey plasma treated with FVIII function-neutralizing antibodies. CONCLUSIONS: TPP2009 specifically targets a unique conformational epitope on ATß*H and blocks ATß-mediated anticoagulation. It effectively promotes coagulation in plasma, indicating the importance of ATß in hemostasis.


Assuntos
Anticorpos/farmacologia , Antitrombina III/metabolismo , Coagulação Sanguínea/efeitos dos fármacos , Coagulantes/farmacologia , Animais , Anticorpos/imunologia , Anticorpos/metabolismo , Especificidade de Anticorpos , Antitrombina III/química , Antitrombina III/imunologia , Sítios de Ligação de Anticorpos , Testes de Coagulação Sanguínea , Linhagem Celular , Técnicas de Visualização da Superfície Celular , Coagulantes/imunologia , Coagulantes/metabolismo , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Mapeamento de Epitopos , Humanos , Ligação Proteica , Estrutura Secundária de Proteína , Coelhos , Relação Estrutura-Atividade , Ressonância de Plasmônio de Superfície , Fatores de Tempo
8.
Br J Cancer ; 111(3): 430-6, 2014 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-24960403

RESUMO

BACKGROUND: Current data suggest that platinum-based combination therapy is the standard first-line treatment for biliary tract cancer. EGFR inhibition has proven beneficial across a number of gastrointestinal malignancies; and has shown specific advantages among KRAS wild-type genetic subtypes of colon cancer. We report the combination of panitumumab with gemcitabine (GEM) and oxaliplatin (OX) as first-line therapy for KRAS wild-type biliary tract cancer. METHODS: Patients with histologically confirmed, previously untreated, unresectable or metastatic KRAS wild-type biliary tract or gallbladder adenocarcinoma with ECOG performance status 0-2 were treated with panitumumab 6 mg kg(-1), GEM 1000 mg m(-2) (10 mg m(-2) min(-1)) and OX 85 mg m(-2) on days 1 and 15 of each 28-day cycle. The primary objective was to determine the objective response rate by RECIST criteria v.1.1. Secondary objectives were to evaluate toxicity, progression-free survival (PFS), and overall survival. RESULTS: Thirty-one patients received at least one cycle of treatment across three institutions, 28 had measurable disease. Response rate was 45% and disease control rate was 90%. Median PFS was 10.6 months (95% CI 5-24 months) and median overall survival 20.3 months (95% CI 9-25 months). The most common grade 3/4 adverse events were anaemia 26%, leukopenia 23%, fatigue 23%, neuropathy 16% and rash 10%. CONCLUSIONS: The combination of gemcitabine, oxaliplatin and panitumumab in KRAS wild type metastatic biliary tract cancer showed encouraging efficacy, additional efforts of genetic stratification and targeted therapy is warranted in biliary tract cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias da Vesícula Biliar/tratamento farmacológico , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Neoplasias do Sistema Biliar/mortalidade , Neoplasias do Sistema Biliar/patologia , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Neoplasias da Vesícula Biliar/mortalidade , Neoplasias da Vesícula Biliar/patologia , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Panitumumabe , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Resultado do Tratamento , Proteínas ras/genética , Gencitabina
9.
Br J Pharmacol ; 171(16): 3814-26, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24749982

RESUMO

BACKGROUND AND PURPOSE: Although serine proteases and agonists of protease-activated receptor 2 (PAR2) cause inflammation and pain, the spectrum of proteases that are activated by proinflammatory and algesic stimuli and their contribution to inflammatory pain are uncertain. EXPERIMENTAL APPROACH: Enzymic assays and selective inhibitors were used to characterize protease activity in mice after intraplantar injections of formalin, bradykinin, PAR2 activating peptide (AP) or vehicle. The capacity of these proteases and of recombinant mouse trypsin 4 to cleave fragments of PAR2 and to activate PAR2 in cell lines was determined. Protease inhibitors and par2 (-/-) mice were used to assess the contributions of proteases and PAR2 to pain and inflammation. KEY RESULTS: Intraplantar injection of formalin, bradykinin or PAR2-AP led to the activation of proteases that were susceptible to the serine protease inhibitor melagatran but resistant to soybean trypsin inhibitor (SBTI). Melagatran inhibited mouse trypsin 4, which degraded SBTI. Proteases generated in inflamed tissues cleaved PAR2-derived peptides. These proteases and trypsin 4 increased [Ca(2+) ]i in PAR2-transfected but not in untransfected cells, and melagatran suppressed this activity. Melagatran or PAR2 deletion suppressed oedema and mechanical hypersensitivity induced by intraplantar formalin, bradykinin and PAR2-AP, but had no effect on capsaicin-induced pain. CONCLUSIONS AND IMPLICATIONS: Diverse proinflammatory and algesic agents activate melagatran-sensitive serine proteases that cause inflammation and pain by a PAR2-mediated mechanism. By inducing self-activating proteases, PAR2 amplifies and sustains inflammation and pain. Serine protease inhibitors can attenuate the inflammatory and algesic effects of diverse stimuli, representing a useful therapeutic strategy.


Assuntos
Inflamação/metabolismo , Dor/metabolismo , Receptor PAR-2/metabolismo , Serina Proteases/metabolismo , Animais , Azetidinas/farmacologia , Benzilaminas/farmacologia , Bradicinina , Linhagem Celular , Feminino , , Formaldeído , Inflamação/induzido quimicamente , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Oligopeptídeos , Dor/induzido quimicamente , Receptor PAR-2/agonistas , Receptor PAR-2/deficiência , Receptor PAR-2/genética , Inibidores de Serina Proteinase/farmacologia , Tripsina/metabolismo
10.
Haemophilia ; 20(4): 593-600, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24471985

RESUMO

Patients with haemophilia (PWH) are usually monitored by the one-stage activated partial thromboplastin time (aPTT) factor VIII (FVIII) assay. Different aPTT activators may affect clotting time (CT) and FVIII:C levels in patients treated with PEGylated FVIII. To evaluate the characteristics of PEGylated FVIII (BAY 94-9027) in various aPTT clotting assays, and to identify suitable aPTT reagents for monitoring BAY 94-9027 during the treatment of PWH, BAY 94-9027 and World Health Organization (WHO) 8th FVIII standards (WHO-8) were spiked into pooled and individual severe haemophilia A plasma at 1.0, 0.25 and 0.05 IU mL(-1) . Five commercial aPTT reagents widely used in clinical laboratories were compared and evaluated for BAY 94-9027 activity in plasma from PWH. BAY 94-9027 and WHO-8 bestowed similar CT and excellent precision when ellagic acid (SynthAFax, Dade Actin, and Cephascreen) aPTT reagents were used. In contrast, BAY 94-9027 showed significantly prolonged CT and poor precision compared with WHO-8 using silica aPTT reagents (APTT-SP and STA PTT 5). Furthermore, free 60-kDa polyethylene glycol (PEG), used for the conjugation of FVIII, showed a dose-dependent prolongation of CT in the APTT-SP assay. There was no effect on the SynthAFax-APTT, prothrombin time, or FXIa-initiated thrombin generation assay, demonstrating that the PEG moiety on FVIII has no general effect on the coagulation cascade. In summary, ellagic aPTT reagents (SynthAFax, Dade Actin, and Cephascreen) are most suitable for evaluating potency of BAY 94-9027 and should be the preferred aPTT reagents used in clinical laboratories for monitoring FVIII activity after infusion of BAY 94-9027 to PWH.


Assuntos
Fator VIII/química , Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Tempo de Tromboplastina Parcial/métodos , Polietilenoglicóis/química , Coagulação Sanguínea/efeitos dos fármacos , Fator VIII/farmacologia , Humanos , Tempo de Tromboplastina Parcial/instrumentação , Polietilenoglicóis/farmacologia , Polietilenoglicóis/uso terapêutico , Dióxido de Silício/química , Resultado do Tratamento
11.
J Thromb Haemost ; 11(9): 1699-706, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23692404

RESUMO

BACKGROUND: The rapid clearance of factor IX (FIX) necessitates frequent intravenous administration to achieve effective prophylaxis for patients with hemophilia B. Subcutaneous administration would be a preferred route of administration but is limited by bioavailability. OBJECTIVES: To improve the pharmacokinetics (PK) and bioavailability of FIX, a screen was performed to identify positions for the introduction of novel glycosylation sites with maximal effect on PK and maintenance of coagulation activity. METHODS: Two hundred fifty-one variants, each containing one additional N-linked glycosylation site, were screened in vitro, and the PK profiles of selected variants mapping to spatially distinct regions of FIX were evaluated in mice. Optimal variants were combined, and their PK and efficacy were determined in mice with hemophilia B. RESULTS: Variants that mapped to spatially distinct regions of the FIX structure exhibited different degrees of improved PK and enabled selection of optimized sites while minimizing the loss of FIX activity. Combining the most effective N-glycan sites in the same FIX molecule resulted in further improvements in PK. An optimized variant containing three novel N-glycan sites (at amino acids 103, 151, and 228), and the activity enhancing 338A variant had double the specific activity of wild-type FIX, exhibited 4.5-fold reduced clearance and 2.4-fold increased subcutaneous bioavailability, and was efficacious at a fivefold lower mass dose than wild-type FIX after subcutaneous injection in a bleeding model in mice with hemophilia B. CONCLUSIONS: Glycoengineering was used to significantly improve the subcutaneous PK and efficacy of FIX and may have advantages for subcutaneous dosing.


Assuntos
Fator IX/farmacocinética , Engenharia de Proteínas , Animais , Disponibilidade Biológica , Modelos Animais de Doenças , Fator IX/administração & dosagem , Fator IX/genética , Fator IX/uso terapêutico , Glicosilação , Células HEK293 , Hemofilia B/tratamento farmacológico , Humanos , Injeções Subcutâneas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutagênese Sítio-Dirigida , Conformação Proteica
12.
Haemophilia ; 19(4): 539-45, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23534820

RESUMO

PEGylation of B-domain deleted factor VIII (PEG-FVIII-BDD) prolongs the half-life of the molecule by approximately twofold in animals (Mei et al., Blood 2010; 116: 270). To investigate the role of von Willebrand factor (vWF) in the catabolism of PEG-FVIII-BDD in vivo, a FVIII-BDD mutant (F8V), which is incapable of binding vWF, was generated by deleting the vWF-binding region in the a3 domain of FVIIII-BDD. F8V was expressed, purified and PEGylated by site-specific conjugation. The biochemical and biological properties of F8V and PEGylated F8V (PEG-F8V) were evaluated in vitro and in vivo. The specific activity of purified F8V by a chromogenic assay was similar to FVIII-BDD and PEGylation had minimal impact on the specific activity of F8V in this assay. Analysis by Biacore indicated that both F8V and PEG-F8V display greatly reduced vWF binding in vitro. Pharmacokinetic studies in FVIII knockout (HaemA) mice showed that the terminal half-life (T1/2 ) of F8V was dramatically reduced relative to FVIII-BDD (0.6 h vs. 6.03 h). PEGylation of F8V promoted a significant increase in T1/2 , although PEGylation did not fully compensate for the loss in vWF binding. PEG-F8V showed a shorter T1/2 than PEG-FVIII-BDD both in HaemA mice (7.7 h vs. 14.3 h) and in Sprague-Dawley male rats (2.0 ± 0.3 h vs. 6.0 ± 0.5 h). These data demonstrated that vWF contributes to the longer T1/2 of PEG-FVIII-BDD. Furthermore, this suggests that the clearance of the FVIII:vWF complex, through vWF receptors, is not the sole factor which places an upper limit on the duration of PEG-FVIII circulation in plasma.


Assuntos
Fator VIII/metabolismo , Polietilenoglicóis/metabolismo , Fator de von Willebrand/metabolismo , Animais , Eletroforese em Gel de Poliacrilamida , Fator VIII/isolamento & purificação , Fator VIII/farmacocinética , Meia-Vida , Humanos , Camundongos , Polietilenoglicóis/farmacocinética , Ligação Proteica , Estrutura Terciária de Proteína , Ratos , Ratos Sprague-Dawley , Deleção de Sequência , Especificidade por Substrato
13.
J Microsc ; 230(Pt 3): 382-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18503663

RESUMO

Tomographic reconstruction by transmission electron microscopy is used to reveal three-dimensional nanoparticle shapes and the stacking configurations of nanoparticle ensembles. Reconstructions are generated from bright-field image tilt series, with a sample tilt range up to +/- 70 degrees, using single or dual tilt axes. We demonstrate the feasibility of this technique for the analysis of nanomaterials, using appropriate acquisition conditions. Tomography reveals both cubic and hexagonal close-packing configurations in multi-layered arrays of size-selected In nanospheres. By tomography and phase-contrast lattice imaging, we relate the three-dimensional shape of PbSe octahedral nanoparticles to the underlying crystal structure. We also confirm simple-cubic packing in multi-layers of PbSe nanocubes and see evidence that the particle shapes have cubic symmetry. The shapes of TiO(2) nanorod bundles are shown by tomographic reconstruction to resemble flattened ellipsoids.


Assuntos
Microscopia Eletrônica de Transmissão/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador , Microscopia Eletrônica de Transmissão/instrumentação , Óxidos/química , Titânio/química
14.
J Parasitol ; 93(5): 1222-5, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18163363

RESUMO

Sarcocystis neurona is the most important cause of equine protozoal myeloencephalitis (EPM), a neurologic disease of the horse. In the present work, the kinetics of S. neurona invasion is determined in the equine model. Six ponies were orally inoculated with 250 x 10(6) S. neurona sporocysts via nasogastric intubation and killed on days 1, 2, 3, 5, 7, and 9 postinoculation (PI). At necropsy, tissue samples were examined for S. neurona infection. The parasite was isolated from the mesenteric lymph nodes at 1, 2, and 7 days PI; the liver at 2, 5, and 7 days PI; and the lungs at 5, 7, and 9 days PI by bioassays in interferon gamma gene knock out mice (KO) and from cell culture. Microscopic lesions consistent with an EPM infection were observed in brain and spinal cord of ponies killed 7 and 9 days PI. Results suggest that S. neurona disseminates quickly in tissue of naive ponies.


Assuntos
Encefalomielite/veterinária , Doenças dos Cavalos/parasitologia , Oocistos/fisiologia , Sarcocystis/fisiologia , Sarcocystis/patogenicidade , Sarcocistose/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Encéfalo/patologia , Encefalomielite/parasitologia , Feminino , Trato Gastrointestinal/parasitologia , Cavalos , Interferon gama/genética , Fígado/parasitologia , Pulmão/parasitologia , Linfonodos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Sarcocystis/isolamento & purificação , Sarcocistose/parasitologia , Medula Espinal/patologia
15.
J Vet Intern Med ; 20(2): 322-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16594589

RESUMO

Equine protozoal myeloencephalitis (EPM) is a serious neurologic disease of horses caused primarily by the protozoal parasite Sarcocystis neurona. Currently available antemortem diagnostic testing has low specificity. The hypothesis of this study was that serum and cerebrospinal fluid (CSF) of horses experimentally challenged with S neurona would have an increased S neurona-specific IgM (Sn-IgM) concentration after infection, as determined by an IgM capture enzyme linked immunoassay (ELISA). The ELISA was based on the S neurona low molecular weight protein SNUCD-1 antigen and the monoclonal antibody 2G5 labeled with horseradish peroxidase. The test was evaluated using serum and CSF from 12 horses experimentally infected with 1.5 million S neurona sporocysts and 16 horses experimentally infected with varying doses (100 to 100,000) of S neurona sporocysts, for which results of histopathologic examination of the central nervous system were available. For horses challenged with 1.5 million sporocysts, there was a significant increase in serum Sn-IgM concentrations compared with values before infection at weeks 2-6 after inoculation (P < .0001). For horses inoculated with lower doses of S neurona, there were significant increases in serum Sn-IgM concentration at various points in time after inoculation, depending on the challenge dose (P < .01). In addition, there was a significant increase between the CSF Sn-IgM concentrations before and after inoculation (P < .0001). These results support further evaluation of the assay as a diagnostic test during the acute phase of EPM.


Assuntos
Ensaio de Imunoadsorção Enzimática/veterinária , Doenças dos Cavalos/diagnóstico , Imunoglobulina M/análise , Sarcocystis/imunologia , Sarcocistose/veterinária , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Doenças dos Cavalos/sangue , Doenças dos Cavalos/líquido cefalorraquidiano , Doenças dos Cavalos/parasitologia , Cavalos , Imunoglobulina M/sangue , Imunoglobulina M/líquido cefalorraquidiano , Imunoglobulina M/imunologia , Sarcocistose/sangue , Sarcocistose/líquido cefalorraquidiano , Sarcocistose/diagnóstico , Sensibilidade e Especificidade , Fatores de Tempo
16.
Hum Genet ; 108(3): 205-10, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11354631

RESUMO

Colorectal cancer (CRC) occurs with an increased incidence in individuals with chronic inflammatory bowel disease (IBD) of the colon. Recent data suggest that a family history of colorectal cancer is an independent risk factor for CRC in IBD, an observation that implies that genetic factors are relevant to the development of CRC in this context. Among the genetic defects associated with CRC, the APC I1307K mutation has been detected nearly exclusively in individuals of Ashkenazi Jewish (AJ) origin, occurring in 6%-7% of the AJ general population and in 10%-28% of AJ with a either a personal or family history of CRC or adenomatous polyps. These findings, together with the increased incidence of IBD in AJ, prompted the current analysis of the contribution of the APC I1307K variant of CRC in AJ IBD patients. APC I1307K carrier frequencies were determined in 306 AJ individuals affected with IBD and 308 of their unaffected relatives ascertained from a family collection obtained for the identification of IBD susceptibility genes. Prevalence of the I1307K variant was not significantly different among individuals with IBD, Crohn's disease, ulcerative colitis, and unaffected relatives (6.9%, 7.6%, 4.7%, and 6.2%, respectively), and the mutation was detected in only one of five IBD-affected individuals with a diagnosis of CRC. These results reveal that IBD patients of AJ origin carry the APC I1307K variant at the same rate as individuals within the general AJ population. Lack of an increased APC I1307K carrier rate suggests that this mutation does not account for the increased CRC susceptibility associated with IBD.


Assuntos
Genes APC/genética , Heterozigoto , Doenças Inflamatórias Intestinais/genética , Judeus/genética , Adulto , Idoso , Substituição de Aminoácidos , Colite/genética , Colite Ulcerativa/genética , Neoplasias Colorretais/complicações , Neoplasias Colorretais/genética , Doença de Crohn/genética , DNA/química , DNA/genética , Análise Mutacional de DNA , Saúde da Família , Feminino , Frequência do Gene , Humanos , Doenças Inflamatórias Intestinais/complicações , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo Conformacional de Fita Simples
17.
Am J Health Syst Pharm ; 58(10): 889-95, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11381493

RESUMO

Residency program directors' attitudes toward residency projects were studied. A questionnaire about the residency project experience was mailed in January 2000 to 446 pharmacy practice residency program and specialty residency program directors in the program database of the American Society of Health-System Pharmacists. Recipients responded to opinion statements on a 5-point scale. Responses to the opinion statements were separated into seven categories for analysis. A total of 278 usable questionnaires were returned, for a raw response rate of 63.6%. During the preceding three years, residency directors had served as primary advisors on 917 projects; 171 had served as advisor on at least one of every type of project allowed in the accreditation standards. Of the 917 projects, 364 were presented at national professional meetings, 124 were published, and 484 were believed to have resulted in a positive change in pharmacy services. There were no significant differences in total response scores among any of the subgroups analyzed. There was strong agreement that residency projects were valuable and should continue to be part of the residency program experience. The directors' views of the importance of original research as a project option were more neutral. Overall residency program directors had positive perceptions of the value of residency projects to both residents and institutions and believed that they should continue to be a requirement of residency programs.


Assuntos
Pessoal Administrativo/psicologia , Atitude do Pessoal de Saúde , Educação de Pós-Graduação em Farmácia/normas , Internato não Médico/normas , Apoio à Pesquisa como Assunto/estatística & dados numéricos , Educação de Pós-Graduação em Farmácia/organização & administração , Humanos , Internato não Médico/organização & administração , Projetos Piloto , Resolução de Problemas , Inquéritos e Questionários , Estados Unidos
18.
J Mol Biol ; 304(4): 645-56, 2000 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-11099386

RESUMO

Escherichia coli alkaline phosphatase (EC 3.1.3.1) belongs to a rare group of enzymes that exhibit intragenic complementation. When certain mutant versions of alkaline phosphatase are combined, the resulting heterodimeric enzymes exhibit a higher level of activity than would be expected based upon the relative activities of the parental enzymes. Nine previously identified alkaline phosphatase complementation mutants were re-examined in this work in order to determine a molecular explanation of intragenic complementation in this experimental system. The locations of these mutations were determined by DNA sequence analysis after PCR amplification of the phosphatase-negative phoA gene. Most of the mutations involved ligands to metal-binding sites. Each of the mutant enzymes was re-created by site-specific mutagenesis, expressed, purified, and kinetically characterized. To investigate cooperativity between the two subunits, we analyzed heterodimeric forms of some of the site-specific mutant enzymes. To enable the isolation of the heterodimeric alkaline phosphatase in pure form, the overall charge of one subunit was altered by replacing the C-terminal Lys residue with three Asp residues. This modification had no effect on the kinetic properties of the enzyme. Heterodimeric alkaline phosphatases were created using two methods: (1) in vitro formation by dissociation at acid pH followed by reassociation at slightly alkaline pH conditions in the presence of zinc and magnesium ions; and (2) in vivo expression from a plasmid carrying two different phoA genes. Increases in k(cat), as well as a large reduction in the p-nitrophenyl phosphate K(m) were observed for certain combinations of mutant enzymes. These results suggest that the structural assembly of E. coli alkaline phosphatase into the dimer induces cooperative interactions between the monomers necessary for the formation of the functional form of the holoenzyme.


Assuntos
Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Teste de Complementação Genética , Mutação/genética , Fosfatase Alcalina/química , Fosfatase Alcalina/isolamento & purificação , Substituição de Aminoácidos/genética , Sítios de Ligação , Cromatografia Líquida de Alta Pressão , Dimerização , Genes Bacterianos/genética , Holoenzimas/química , Holoenzimas/genética , Holoenzimas/isolamento & purificação , Holoenzimas/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Magnésio/metabolismo , Modelos Moleculares , Estrutura Quaternária de Proteína , Subunidades Proteicas , Eletricidade Estática , Zinco/metabolismo
19.
Am J Health Syst Pharm ; 57 Suppl 2: S28-31, 2000 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11057365

RESUMO

The use of benchmarking data to evaluate and support pharmacy programs in health systems is discussed. Benchmarking is a method of comparing the outcomes of health care products, services, and practices at an institution against those of competitors in order to learn what might be improved. Benchmarking programs can provide valuable feedback about both positive and negative outcomes. However, it is imperative to avoid inappropriate comparisons and inappropriate assessments. Ideal services for benchmarking are those that have a good likelihood of improving patient care and other outcomes. Successful benchmarking requires sound and thorough data, which is why as many health systems as possible should participate in a benchmarking program. The National Committee for Quality Assurance has formulated guidelines that should enable health systems to develop an information framework that will improve their ability to collect and use data for benchmarking. Standardization in collecting and submitting information is important because it enables institutions to share data easily. Benchmarking can help health-system pharmacists understand the value and outcomes of efforts by their colleagues at other institutions. In addition, benchmarking can help convince health-system administrators of the value of pharmaceutical services in terms of patient care and the bottom line. Benchmarking provides a means of evaluating and supporting the development of pharmacy programs that improve care and save money.


Assuntos
Benchmarking , Serviço de Farmácia Hospitalar , Humanos , Farmacêuticos , Garantia da Qualidade dos Cuidados de Saúde
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