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1.
J Strength Cond Res ; 36(8): 2115-2120, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32282531

RESUMO

ABSTRACT: Swift, MC, Townsend, R, Edwards, D, and Loudon, J. Testing to identify submaximal effort: Lifting to a perceived 50% effort vs. an assigned submaximal load. J Strength Cond Res 36(8): 2115-2120, 2022-The ability to accurately measure effort during postinjury functional testing allows for the validation of displayed physical limitations by injured workers. The Cross-Reference Testing System (XRTS) has been developed to identify submaximal efforts through distraction-based dynamic material handling testing. The XRTS material handling assessment compares dynamic lifts of weights in a crate and lifts using a lever arm device. The purpose of this study was to determine whether subjects lifting an assigned submaximal load influence test results compared with subjects lifting to but not exceeding a 50% perceived effort. Subjects in group A ( n = 35) were assigned the condition to attempt to lift to but not exceed a randomly assigned weight value for both the crate lift and XRTS at 3 lifting heights. Subjects in group B ( n = 32) were asked to lift to but not exceed 37.5 lb from the same 3 lifting heights. The reproducibility of effort was measured with current validity criteria for distraction-based material handling testing. Using the percent difference values, a 2 × 3 (group, lifting height) analysis of variance (ANOVA) was performed to test the hypothesis. The alpha level was set at 0.05. The mean percent change between comparative lifts was 31.13%, 95% CI (22.51-39.75) for group A and 29.26% 95% CI (21.91-36.61) for group B. The 2 × 3 ANOVA demonstrated no significant difference ( p = 0.751) between groups. The results indicate attempting to lift to a perceived 50% effort was not significantly different from attempting to lift to but not exceed an assigned submaximal load.


Assuntos
Remoção , Análise de Variância , Humanos , Reprodutibilidade dos Testes
2.
J Shoulder Elbow Surg ; 30(1): 140-145, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32534211

RESUMO

BACKGROUND: Revision total elbow arthroplasty (TEA) is a challenging procedure that is becoming increasingly common. In our unit, we regard it as essential to exclude infection as the underlying cause of TEA loosening. In all patients with arthroplasty loosening, we undertake a careful history and examination, perform radiographs, monitor inflammatory markers, and undertake a joint aspiration. If any investigation suggests infection as the etiology, then a 2-stage revision is undertaken. Open biopsies are not routinely performed. The aim was to ascertain from our outcomes whether it is safe to perform a single-stage revision for presumed aseptic loosening using these criteria. METHODS: A retrospective review of a consecutive series of revision TEAs was performed in our unit over a 10-year period (2008-2018). Single-stage revisions performed for presumed aseptic loosening were identified. Case notes, radiographs, bloods, aspiration results, and microbiology of tissue samples taken at revision were reviewed. RESULTS: A total of 123 revision elbow arthroplasty cases were performed in the study period. Sixty cases were revised for preoperatively proven infection, instability, or implant failure and were excluded from this study. In 63 cases, aseptic loosening was diagnosed based on history, clinical examination, blood markers, and aspiration. There were 21 dual-component and 42 single-component revisions. In the dual-component revision group, tissue samples taken at the time of revision were positive in only 1 case (5%). In the single-component revision group, positive culture samples were present in 3 cases (7%). χ2 analysis showed no significant difference between single- and dual-component revisions (P = .76). No cases with positive culture samples from either group have required subsequent revision surgery. CONCLUSION: Given the results of this study, we conclude that is safe to perform single-stage revision arthroplasty for implant loosening based on history, examination, normal inflammatory markers, and negative aspiration results without the need for open biopsy.


Assuntos
Artroplastia de Substituição do Cotovelo , Falha de Prótese , Infecções Relacionadas à Prótese/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Substituição do Cotovelo/efeitos adversos , Artroplastia de Substituição do Cotovelo/métodos , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/sangue , Reoperação/métodos , Estudos Retrospectivos
3.
J Monet Econ ; 117: 1-18, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33716384

RESUMO

A general equilibrium model featuring multiple realistic sources of financial frictions is developed to study how different constraints interact in equilibrium. We highlight, distinguish, and evaluate their differential impacts and rich interactions. The economic impact of financial inclusion policies in an economy depends not only on which constraint is alleviated, but also on the tightness of other constraints. Policy instruments should target the most binding constraint, which likely varies across countries. Moreover, there are important tradeoffs between financial inclusion, GDP, and the distribution of income. The transitional dynamics also differ from those in steady states. Policy makers should consider both.

4.
Proc Natl Acad Sci U S A ; 114(24): 6176-6184, 2017 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-28592655

RESUMO

We use a variety of different datasets from Thailand to study not only the extremes of micro and macro variables but also within-country flow of funds and labor migration. We develop a general equilibrium model that encompasses regional variation in the type of financial friction and calibrate it to measured variation in regional aggregates. The model predicts substantial capital and labor flows from rural to urban areas even though these differ only in the underlying financial regime. Predictions for micro variables not used directly provide a model validation. Finally, we estimate the impact of a policy of counterfactual, regional isolationism.


Assuntos
Desenvolvimento Econômico , Administração Financeira/economia , Administração Financeira/estatística & dados numéricos , População Rural , População Urbana , Bases de Dados Factuais , Humanos , Fatores Socioeconômicos , Tailândia
5.
J Craniofac Surg ; 31(7): 2088-2091, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32649556

RESUMO

Spring-assisted surgery (SAS) has been shown to be an effective technique for correction of isolated sagittal craniosynostosis in patients less than 6 months of age. At their institution, the authors adopted a minimally invasive technique in 2010, using a shorter incision and an endoscope. A retrospective chart review of 101 patients with isolated, nonsyndromic, sagittal craniosynostosis, who underwent SAS, was performed in order to compare perioperative and clinical outcomes of the open (n = 51) and minimally-invasive (n = 50) approaches. Surgeries were performed by 2 neurosurgeons and 3 plastic surgeons, between 2005 and 2018. The pre and postoperative cephalic indices were not significantly different in both groups. Minimally-invasive spring placement required a longer operative time than the open approach, with the mean minimally-invasive operative time at 65 minutes, compared to 53 minutes (P < 0.0001). Spring removal operative time was not significantly different, with the minimally-invasive operative time at 31 minutes versus 29 minutes (P = 0.48). There were no significant differences in major or minor complications when comparing the open and minimally-invasive approaches. In conclusion, both the open and the minimally-invasive SAS techniques are effective for early correction of isolated sagittal craniosynostosis, although the minimally-invasive approach requires a longer operative time for spring placement.


Assuntos
Craniossinostoses/cirurgia , Craniotomia , Humanos , Lactente , Neuroendoscopia/métodos , Complicações Pós-Operatórias , Procedimentos de Cirurgia Plástica , Estudos Retrospectivos , Equipamentos Cirúrgicos , Resultado do Tratamento
6.
Am J Transplant ; 18(9): 2305-2313, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29767445

RESUMO

Preventing conversion of donor-specific anti-HLA antibodies (DSAs) from an IgM-to-IgG could a way to prevent chronic rejection. We evaluated whether belatacept-treated patients (belatacept less-intensive [LI] or more-intensive [MI] regimens) have a lower rate of conversion than do cyclosporine A (CsA)-treated patients. We included 330 HLA-mismatched patients from 2 phase 3 trials with either (a) complete donor/recipient HLA-A, -B, -DR, and -DQ loci typing or (b) incomplete HLA typing with IgG DSAs detected pretransplant or posttransplant. IgM and IgG DSAs were tested with single antigen beads at 0, 6, 12, 24, and 36 months posttransplant. The overall (preexisting or de novo) rates of IgM- and IgG-positive DSAs were 29% and 34%, respectively. The pretransplant IgM and IgG DSA-positive frequencies were similar between treatment groups. The IgG-positive dnDSA rate was significantly higher in the CsA-treated group (34%) compared with the belatacept-LI (8%) and belatacept-MI (11%) (P < .001) groups. In IgM-positive dnDSA patients, the IgG-positive dnDSA rate of conversion was 2.8 times higher in the CsA group than in the combined belatacept groups (P = .006). However, the observed association between belatacept treatment and more limited conversion of IgM-to-IgG dnDSAs was based on a limited number of patients and requires further validation.


Assuntos
Rejeição de Enxerto/etiologia , Antígenos HLA/imunologia , Imunoglobulina A/imunologia , Imunoglobulina M/imunologia , Imunossupressores/uso terapêutico , Isoanticorpos/efeitos adversos , Transplante de Rim/efeitos adversos , Abatacepte/uso terapêutico , Calcineurina/uso terapêutico , Feminino , Seguimentos , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/imunologia , Teste de Histocompatibilidade , Humanos , Imunoglobulinas Intravenosas/administração & dosagem , Imunoglobulinas Intravenosas/imunologia , Falência Renal Crônica/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Doadores de Tecidos
7.
Nature ; 551(7682): 565, 2017 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-29189804

Assuntos
Pesquisa , Humanos
8.
Artigo em Inglês | MEDLINE | ID: mdl-28971866

RESUMO

Quantitative whole-body autoradiography was used to assess the distribution and tissue penetration of isavuconazole in rats following single and repeated oral-dose administration of radiolabeled isavuconazonium sulfate, the prodrug of isavuconazole. Following a single-dose administration of radiolabeled isavuconazonium sulfate (labeled on the active moiety), radioactivity was detectable within 1 h postdose in 56 of 65 tissue/fluid specimens. The highest maximum concentrations (Cmax) were observed in bile and liver (66.6 and 24.7 µg eq/g, respectively). The lowest Cmax values were in bone and eye lens (0.070 and 0.077 µg eq/g, respectively). By 144 h postdose, radioactivity was undetectable in all tissues/fluids except liver (undetectable at 336 h) and adrenal gland tissues (undetectable at 672 h). Following daily administration for up to 21 days, 1-h-postdose Cmax values were the highest on or before day 14 in all except seven tissues/fluids, of which only rectum mucosa and small intestine mucosa had Cmax values >25% higher than all other 1-h-postdose values. For 24-h-postdose Cmax values, only large intestine, large intestine mucosa, and urine had the highest Cmax values at day 21. The penetration of single oral doses of unlabeled isavuconazole (25 mg/kg of body weight isavuconazonium sulfate) and voriconazole (50 mg/kg) into rat brain (assessed using liquid chromatography-tandem mass spectrometry) was also compared. Brain concentration/plasma concentration ratios reached approximately 1.8:1 and 2:1, respectively. These data suggest that isavuconazole penetrates most tissues rapidly, reaches a steady state in most or all tissues/fluids within 14 days, does not accumulate in tissues/fluids over time, and achieves potentially efficacious concentrations in the brain.


Assuntos
Encéfalo/metabolismo , Nitrilas/farmacocinética , Piridinas/farmacocinética , Triazóis/farmacocinética , Voriconazol/farmacocinética , Administração Oral , Glândulas Suprarrenais/metabolismo , Animais , Autorradiografia , Bile/metabolismo , Osso e Ossos/metabolismo , Mucosa Intestinal/metabolismo , Infecções Fúngicas Invasivas/tratamento farmacológico , Cristalino/metabolismo , Fígado/metabolismo , Masculino , Nitrilas/metabolismo , Pró-Fármacos/análise , Pró-Fármacos/metabolismo , Piridinas/metabolismo , Ratos , Ratos Long-Evans , Ratos Sprague-Dawley , Ratos Wistar , Distribuição Tecidual , Triazóis/metabolismo , Voriconazol/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-28923872

RESUMO

Isavuconazole, the active moiety of the water-soluble prodrug isavuconazonium sulfate, is a triazole antifungal agent for the treatment of invasive fungal infections. The purpose of this analysis was to characterize the isavuconazole exposure-response relationship for measures of efficacy and safety in patients with invasive aspergillosis and infections by other filamentous fungi from the SECURE clinical trial. Two hundred thirty-one patients who received the clinical dosing regimen and had exposure parameters were included in the analysis. The primary drug exposure parameters included were predicted trough steady-state plasma concentrations, predicted trough concentrations after 7 and 14 days of drug administration, and area under the curve estimated at steady state (AUCss). The exposure parameters were analyzed against efficacy endpoints that included all-cause mortality through day 42 in the intent-to-treat (ITT) and modified ITT populations, data review committee (DRC)-adjudicated overall response at end of treatment (EOT), and DRC-adjudicated clinical response at EOT. The safety endpoints analyzed were elevated or abnormal alanine aminotransferase, increased aspartate aminotransferase, and a combination of the two. The endpoints were analyzed using logistic regression models. No statistically significant relationship (P > 0.05) was found between isavuconazole exposure and either efficacy or safety endpoints. The lack of association between exposure and efficacy indicates that the isavuconazole exposures achieved by clinical dosing were appropriate for treating the infecting organisms in the SECURE study and that increases in alanine or aspartate aminotransferase were not related to increase in exposures. Without a clear relationship, there is no current clinical evidence for recommending routine therapeutic drug monitoring for isavuconazole.


Assuntos
Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Infecções Fúngicas Invasivas/tratamento farmacológico , Nitrilas/uso terapêutico , Piridinas/uso terapêutico , Triazóis/uso terapêutico , Alanina Transaminase/sangue , Antifúngicos/farmacocinética , Aspartato Aminotransferases/sangue , Relação Dose-Resposta a Droga , Monitoramento de Medicamentos , Humanos , Nitrilas/farmacocinética , Piridinas/farmacocinética , Triazóis/farmacocinética
10.
J Nucl Cardiol ; 24(1): 57-65, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-26607361

RESUMO

BACKGROUND: Regadenoson is a selective A2A adenosine receptor agonist indicated for radionuclide myocardial perfusion imaging in patients unable to undergo adequate exercise stress. However, the safety, tolerability, and plasma concentrations associated with repeated doses have not previously been assessed. METHOD AND RESULTS: Healthy males and females were randomized to receive intravenous regadenoson [100 µg (3 doses), 200 µg (3 doses), or 400 µg (2 doses)], or placebo (2 or 3 doses; 0.9% sodium chloride); all doses 10 minutes apart. The primary endpoint was vital sign measurements (blood pressure and heart rate). Secondary endpoints included 12-lead electrocardiogram measurements, clinical laboratory evaluations (hematology, chemistry, and urinalysis), and adverse events. Thirty-six subjects were randomized and completed the study. Plasma concentrations of regadenoson increased in a dose-related manner and with successive doses. No consistent effect was observed for systolic blood pressure, although diastolic blood pressure was slightly lower than placebo for all regadenoson groups. Transient, dose-dependent increases in heart rate were observed in all regadenoson groups. There were no serious adverse events; 27 adverse events occurred in 14 regadenoson-treated subjects vs two events in two placebo-treated subjects. CONCLUSION: Repeated doses of regadenoson appeared to be safe and well tolerated in healthy subjects.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Teste de Esforço/efeitos adversos , Teste de Esforço/métodos , Purinas/efeitos adversos , Pirazóis/efeitos adversos , Vasodilatadores/efeitos adversos , Adolescente , Adulto , Idoso , Relação Dose-Resposta a Droga , Tolerância a Medicamentos , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio , Efeito Placebo , Purinas/administração & dosagem , Pirazóis/administração & dosagem , Valores de Referência , Medição de Risco , Resultado do Tratamento , Vasodilatadores/administração & dosagem , Adulto Jovem
11.
Transpl Infect Dis ; 19(5)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28722255

RESUMO

Patients undergoing treatment with immunosuppressant drugs following solid organ or hematopoietic stem cell transplantation are at particular risk for development of serious infections such as invasive aspergillosis. Four triazole antifungal drugs, voriconazole, posaconazole, itraconazole, and isavuconazole, are approved to treat invasive aspergillosis either as first- or second-line therapy. All of these agents are inhibitors of cytochrome P450 3A4, which plays a key role in metabolizing immunosuppressant drugs such as cyclosporine, tacrolimus, and sirolimus. Thus, co-administration of a triazole antifungal drug with these immunosuppressant drugs can potentially increase plasma concentrations of the immunosuppressant drugs, thereby resulting in toxicity, or upon discontinuation, inadvertently decrease the respective concentrations with increased risk of rejection or graft-versus-host disease. In this article, we review the evidence for the extent of inhibition of cytochrome P450 3A4 by each of these triazole antifungal drugs and assess their effects on cyclosporine, tacrolimus, and sirolimus. We also consider other factors affecting interactions of these two classes of drugs. Finally, we examine recommendations and strategies to evaluate and address those potential drug-drug interactions in these patients.


Assuntos
Antifúngicos/farmacocinética , Aspergilose/tratamento farmacológico , Sistema Enzimático do Citocromo P-450/metabolismo , Imunossupressores/farmacocinética , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Interações Medicamentosas , Humanos , Imunossupressores/administração & dosagem
12.
Eur J Clin Pharmacol ; 73(6): 669-678, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28271239

RESUMO

PURPOSE: The purpose of the study is to evaluate the effect of renal impairment (RI) and end-stage renal disease (ESRD) on the pharmacokinetics (PK) of isavuconazole and the inactive cleavage product, BAL8728. METHODS: A single intravenous dose of the prodrug isavuconazonium sulfate (372 mg, equivalent to 200 mg isavuconazole and 75 mg of BAL8728 cleavage product) was administered to healthy controls (parts 1 and 2) and participants with mild, moderate, or severe RI (part 2) or ESRD (part 1); ESRD participants received two doses of 200 mg isavuconazole, 1 h post-dialysis (day 1) and prior to dialysis (day 15). Plasma PK parameters for isavuconazole included maximum concentration (C max), area under the concentration-time curve (AUC) from time of dose to 72 h (AUC72), AUC extrapolated to infinity (AUC∞), AUC to last measurable concentration (AUClast), half-life (t ½ h), volume of distribution (V z), and total clearance (CL), for the healthy control group versus those with mild, moderate, or severe RI or ESRD. RESULTS: Isavuconazole C max values were 4% higher in mild RI and 7, 14, and 21% lower in participants with moderate RI, severe RI, or ESRD versus the healthy control group, respectively. When hemodialysis occurred post-dose (day 15), participants with ESRD had a 30% increase in AUC72 for isavuconazole in parallel with reduction of extracellular volume induced by dialysis. Exposure (AUC∞ and AUClast) was not significantly different for participants with mild, moderate, or severe RI versus healthy controls although there was considerable variability. The t1/2 (day 1) was 125.5 ± 63.6 h (healthy control group), 204.5 ± 82.6 h (ESRD group) in part 1, and 140.5 ± 77.7 h (healthy control group), 117.0 ± 66.2 h (mild RI), 158.5 ± 56.4 h (moderate RI), and 145.8 ± 65.8 L/h (severe RI) in part 2. CL was 2.4 ± 0.8 L/h (healthy control group) and 2.9 ± 1.3 L/h (ESRD group) in part 1 and 2.4 ± 1.2 L/h (healthy control group), 2.5 ± 1.0 L/h (mild RI), 2.2 ± 0.8 L/h (moderate RI), and 2.4 ± 0.8 L/h (severe RI) in part 2. The V z was 382.6 ± 150.6 L in the healthy control group and 735.6 ± 277.3 L in ESRD patients on day 1 in part 1 of the study. In part 2 of the study, V z was 410.8 ± 89.7 L in the healthy control group, 341.6 ± 72.3 L in mild RI, 509.1 ± 262.2 L in moderate RI, and 439.4 L in severe RI. CONCLUSIONS: Based on the findings of this study, dose adjustments of isavuconazole are unlikely to be required in individuals with RI or in those with ESRD who receive hemodialysis.


Assuntos
Falência Renal Crônica/metabolismo , Nitrilas/farmacocinética , Piridinas/farmacocinética , Diálise Renal , Insuficiência Renal/metabolismo , Triazóis/farmacocinética , Administração Intravenosa , Adulto , Idoso , Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Área Sob a Curva , Estudos de Casos e Controles , Relação Dose-Resposta a Droga , Feminino , Meia-Vida , Humanos , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Nitrilas/administração & dosagem , Piridinas/administração & dosagem , Insuficiência Renal/fisiopatologia , Distribuição Tecidual , Triazóis/administração & dosagem , Adulto Jovem
13.
J Shoulder Elbow Surg ; 26(9): 1553-1561, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28359693

RESUMO

BACKGROUND: Recent studies have identified the diagnostic challenge of low-grade infections after shoulder arthroplasty surgery. Infections after nonarthroplasty procedures have not been reported. This study assessed patient-related risk factors, outcomes, and clinical presentation of low-grade infection after open and arthroscopic nonarthroplasty shoulder surgery. METHODS: The cases of 35 patients presenting with suspected low-grade infection were reviewed. Biopsy specimens taken at revision surgery were cultured in the sterile environment of a class II laminar flow cabinet and incubated for a minimum of 14 days at a specialist orthopedic microbiology laboratory. Patient-related factors (age, occupation, injection), index surgery, and infection characteristics (onset of symptoms, duration to diagnosis, treatment) were analyzed. RESULTS: Positive cultures were identified in 21 cases (60.0%), of which 15 were male patients (71%). Of all patients with low-grade infection, 47.6% were male patients between 16 and 35 years of age. Propionibacterium acnes and coagulase-negative staphylococcus were the most common organisms isolated (81.1% [n = 17] and 23.8% [n = 5], respectively). Of 14 negative culture cases, 9 were treated with early empirical antibiotics (64.3%); 7 patients reported symptomatic improvement (77.8%). Of 5 patients treated with late empirical antibiotics, 4 stated improvement. Patients presented with symptoms akin to resistant postoperative frozen shoulder (persistent pain and stiffness, unresponsive to usual treatments). CONCLUSION: Young male patients are at greatest risk for low-grade infections after arthroscopic and open nonarthroplasty shoulder surgery. P. acnes was the most prevalent organism. Patients presented with classic postoperative frozen shoulder symptoms, resistant to usual treatments. Interestingly, 78.6% of patients with negative cultures responded positively to empirical treatment.


Assuntos
Artroscopia/efeitos adversos , Infecções por Bactérias Gram-Positivas/microbiologia , Complicações Pós-Operatórias/microbiologia , Propionibacterium acnes/isolamento & purificação , Articulação do Ombro/cirurgia , Infecções Estafilocócicas/microbiologia , Adolescente , Adulto , Idoso , Antibacterianos/uso terapêutico , Coagulase/metabolismo , Feminino , Infecções por Bactérias Gram-Positivas/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Reoperação , Estudos Retrospectivos , Fatores de Risco , Articulação do Ombro/microbiologia , Infecções Estafilocócicas/diagnóstico , Staphylococcus/enzimologia , Adulto Jovem
14.
Antimicrob Agents Chemother ; 60(5): 3025-31, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26953193

RESUMO

Isavuconazole, administered as the prodrug isavuconazonium sulfate, was recently approved by the U.S. Food and Drug Administration and the European Medicines Agency for the treatment of adults with invasive aspergillosis and mucormycosis. The objective of this analysis was to develop a population pharmacokinetic model using NONMEM (version 7.2) for subjects with hepatic impairment, using intravenous and oral administration data from two hepatic studies, and to simulate concentration profiles to steady state, thus evaluating the need for dose adjustment. A two-compartment model with Weibull absorption function and first-order elimination process adequately described plasma isavuconazole concentrations. The population mean clearance in healthy subjects was 2.5 liters/h (5th and 95th percentiles: 2.0 and 3.1). The mean clearance values for subjects with mild and moderate hepatic impairment decreased approximately to 1.55 liters/h (5th and 95th percentiles: 1.3 and 1.8 liters/h) and 1.32 liters/h (5th and 95th percentiles: 1.05 and 1.35), respectively. Peripheral volume of distribution increased with body mass index. Simulations of mean concentration time profiles to steady state showed less than a 2-fold increase in mean trough concentrations for subjects with mild and moderate hepatic impairment compared with healthy subjects. After administration of the single dose, safety data for subjects with mild and moderate hepatic impairment were generally comparable to those for healthy subjects in both studies. Due to the <2-fold increase in trough concentrations and the established safety margin, dose adjustment appears to be unnecessary in subjects with mild or moderate hepatic impairment.


Assuntos
Hepatopatias/metabolismo , Fígado/metabolismo , Fígado/patologia , Nitrilas/farmacocinética , Piridinas/farmacocinética , Triazóis/farmacocinética , Administração Oral , Feminino , Voluntários Saudáveis , Humanos , Masculino , Modelos Teóricos , Nitrilas/administração & dosagem , Piridinas/administração & dosagem , Triazóis/administração & dosagem
15.
Antimicrob Agents Chemother ; 60(9): 5483-91, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27381396

RESUMO

Isavuconazole, the active moiety of the water-soluble prodrug isavuconazonium sulfate, is a triazole antifungal agent used for the treatment of invasive fungal infections. The objective of this analysis was to develop a population pharmacokinetic (PPK) model to identify covariates that affect isavuconazole pharmacokinetics and to determine the probability of target attainment (PTA) for invasive aspergillosis patients. Data from nine phase 1 studies and one phase 3 clinical trial (SECURE) were pooled to develop the PPK model (NONMEM, version 7.2). Stepwise covariate modeling was performed in Perl-speaks-NONMEM, version 3.7.6. The area under the curve (AUC) at steady state was calculated for 5,000 patients by using Monte Carlo simulations. The PTA using the estimated pharmacodynamic (PD) target value (total AUC/MIC ratio) estimated from in vivo PD studies of invasive aspergillosis over a range of MIC values was calculated using simulated patient AUC values. A two-compartment model with a Weibull absorption function and a first-order elimination process adequately described plasma isavuconazole concentrations. The mean estimate for isavuconazole clearance was 2.360 liters/h (percent coefficient of variation [%CV], 34%), and the mean AUC from 0 to 24 h (AUC0-24) was ∼100 mg·h/liter. Clearance was approximately 36% lower in Asians than in Caucasians. The PTA calculated over a range of MIC values by use of the nonneutropenic murine efficacy index corresponding to 90% survival indicated that adequate isavuconazole exposures were achieved in >90% of simulated patients to treat infections with MICs up to and including 1 mg/liter according to European Committee on Antimicrobial Susceptibility Testing methodology and in >90% of simulated patients for infections with MICs up to and including 0.5 mg/liter according to Clinical and Laboratory Standards Institute methodology. The highest MIC result for PTA was the same for Caucasian and Asian patients.


Assuntos
Antifúngicos/farmacocinética , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergillus/efeitos dos fármacos , Fungos/efeitos dos fármacos , Nitrilas/farmacocinética , Nitrilas/uso terapêutico , Piridinas/farmacocinética , Piridinas/uso terapêutico , Triazóis/farmacocinética , Triazóis/uso terapêutico , Área Sob a Curva , Humanos , Testes de Sensibilidade Microbiana , Método de Monte Carlo , Probabilidade
16.
Antimicrob Agents Chemother ; 60(8): 4568-76, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27185799

RESUMO

Isavuconazonium sulfate (Cresemba; Astellas Pharma Inc.), a water-soluble prodrug of the triazole antifungal agent isavuconazole, is available for the treatment of invasive aspergillosis (IA) and invasive mucormycosis. A population pharmacokinetic (PPK) model was constructed using nonparametric estimation to compare the pharmacokinetic (PK) behaviors of isavuconazole in patients treated in the phase 3 VITAL open-label clinical trial, which evaluated the efficacy and safety of the drug for treatment of renally impaired IA patients and patients with invasive fungal disease (IFD) caused by emerging molds, yeasts, and dimorphic fungi. Covariates examined were body mass index (BMI), weight, race, impact of estimated glomerular filtration rate (eGFR) on clearance (CL), and impact of weight on volume. PK parameters were compared based on IFD type and other patient characteristics. Simulations were performed to describe the MICs covered by the clinical dosing regimen. Concentrations (n = 458) from 136 patients were used to construct a 2-compartment model (first-order absorption compartment and central compartment). Weight-related covariates affected clearance, but eGFR did not. PK parameters and intersubject variability of CL were similar across different IFD groups and populations. Target attainment analyses demonstrated that the clinical dosing regimen would be sufficient for total drug area under the concentration-time curve (AUC)/MIC targets ranging from 50.5 for Aspergillus spp. (up to the CLSI MIC of 0.5 mg/liter) to 270 and 5,053 for Candida albicans (up to MICs of 0.125 and 0.004 mg/liter, respectively) and 312 for non-albicans Candida spp. (up to a MIC of 0.125 mg/liter). The estimations for Candida spp. were exploratory considering that no patients with Candida infections were included in the current analyses. (The VITAL trial is registered at ClinicalTrials.gov under number NCT00634049.).


Assuntos
Antifúngicos/farmacocinética , Nitrilas/farmacocinética , Piridinas/farmacocinética , Triazóis/farmacocinética , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergillus/efeitos dos fármacos , Candida/efeitos dos fármacos , Feminino , Humanos , Modelos Lineares , Masculino , Testes de Sensibilidade Microbiana , Mucormicose/tratamento farmacológico , Nitrilas/uso terapêutico , Piridinas/uso terapêutico , Triazóis/uso terapêutico
17.
Int J Clin Pharmacol Ther ; 54(8): 572-80, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27345284

RESUMO

OBJECTIVE/METHODS: Two openlabel, single-dose, randomized crossover studies and one open-label, multiple-dose, parallel group study in healthy volunteers were conducted with the prodrug, isavuconazonium sulfate, to determine absolute bioavailability of the active triazole, isavuconazole (EudraCT 2007-004949-15; n = 14), and the effect of food (EudraCT 2007- 004940-63; n = 26), and pH (NCT02128893; n = 24) on the absorption of isavuconazole. Isavuconazonium sulfate 744 mg designed to deliver 400 mg of the active triazole isavuconazole was administered in the absolute bioavailability (oral or intravenous (IV) (2-hour infusion)) and food-effect studies (oral). In the pH-effect study, isavuconazonium sulfate 372 mg designed to deliver 200 mg of isavuconazole was administered orally three times daily (t.i.d.) for 2 days, followed by a single daily oral dose for 3 days, in the presence of steady state esomeprazole dosed orally at 40 mg/day. RESULTS: Isavuconazole was well tolerated in each study. Bioavailability: Geometric least squares mean ratios (GLSMR; oral/IV) for isavuconazole AUC∞, and Cmax were 98% (90% confidence interval (CI): 94, 101) and 78% (90% CI: 72, 85), respectively. Food-effect: GLSMR (fed/fasted) for AUC∞ and Cmax of isavuconazole in plasma were 110% (90% CI: 102, 118) and 92% (90% CI: 86, 98), respectively. Median tmax was 5 hours with food and 3 hours under fasted conditions. pH-effect: GLSMR for isavuconazole AUCtau and Cmax were 108% (90% CI: 89, 130) and 105% (90% CI: 89, 124), respectively. CONCLUSIONS: Orally administered isavuconazonium sulfate effectively delivers isavuconazole, as evidenced by the fact that oral isavuconazole is bioequivalent to the IV formulation. Dose adjustments are not required when switching between oral and IV formulations, regardless of food or drugs that increase gastric pH.


Assuntos
Interações Alimento-Droga , Nitrilas/farmacocinética , Piridinas/farmacocinética , Triazóis/farmacocinética , Administração Intravenosa , Administração Oral , Adulto , Disponibilidade Biológica , Estudos Cross-Over , Interações Medicamentosas , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Nitrilas/administração & dosagem , Piridinas/administração & dosagem , Estômago/química , Triazóis/administração & dosagem
18.
J Proteome Res ; 14(2): 1238-49, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25541672

RESUMO

The proteomic analysis of bronchoalveolar lavage fluid (BALF) can give insight into pulmonary disease pathology and response to therapy. Here, we describe the first gel-free quantitative analysis of BALF in idiopathic pulmonary fibrosis (IPF), a chronic and fatal scarring lung disease. We utilized two-dimensional reversed-phase liquid chromatography and ion-mobility-assisted data-independent acquisition (HDMSE) for quantitation of >1000 proteins in immunodepleted BALF from the right middle and lower lobes of normal controls and patients with IPF. Among the analytes that were increased in IPF were well-described mediators of pulmonary fibrosis (osteopontin, MMP7, CXCL7, CCL18), eosinophil- and neutrophil-derived proteins, and proteins associated with fibroblast foci. For additional discovery and targeted validation, BALF was also screened by multiple reaction monitoring (MRM), using the JPT Cytokine SpikeMix library of >400 stable isotope-labeled peptides. A refined MRM assay confirmed the robust expression of osteopontin, and demonstrated, for the first time, upregulation of the pro-fibrotic cytokine, CCL24, in BALF in IPF. These results show the utility of BALF proteomics for the molecular profiling of fibrotic lung diseases and the targeted quantitation of soluble markers of IPF. More generally, this study addresses critical quality control measures that should be widely applicable to BALF profiling in pulmonary disease.


Assuntos
Líquido da Lavagem Broncoalveolar , Fibrose Pulmonar Idiopática/metabolismo , Proteômica , Eletroforese em Gel de Poliacrilamida , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
19.
J Antimicrob Chemother ; 70(3): 780-3, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25326086

RESUMO

OBJECTIVES: To assess the performance of the Gram-negative-specific antibiotic temocillin in polymethylmethacrylate bone cement pre-loaded with gentamicin, as a strategy for local antibiotic delivery. METHODS: Temocillin was added at varying concentrations to commercial gentamicin-loaded bone cement. The elution of the antibiotic from cement samples over a 2 week period was quantified by LC-MS. The eluted temocillin was purified by fast protein liquid chromatography and the MICs for a number of antibiotic-resistant Escherichia coli were determined. The impact strength of antibiotic-loaded samples was determined using a Charpy-type impact testing apparatus. RESULTS: LC-MS data showed temocillin eluted to clinically significant concentrations within 1 h in this laboratory system and the eluted temocillin retained antimicrobial activity against all organisms tested. Impact strength analysis showed no significant difference between cement samples with or without temocillin. CONCLUSIONS: Temocillin can be added to bone cement and retains its antimicrobial activity after elution. The addition of up to 10% temocillin did not affect the impact strength of the cement. The results show that temocillin is a promising candidate for use in antibiotic-loaded bone cement.


Assuntos
Anti-Infecciosos Locais/farmacocinética , Antibioticoprofilaxia/métodos , Cimentos Ósseos/química , Portadores de Fármacos , Escherichia coli/efeitos dos fármacos , Procedimentos Ortopédicos/métodos , Penicilinas/farmacocinética , Cromatografia Líquida , Humanos , Espectrometria de Massas
20.
J Pediatr Hematol Oncol ; 37(1): e45-50, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25072363

RESUMO

Micafungin is a potent echinocandin antifungal that can be used for both prophylaxis and treatment of Candida infections. This open-label study assessed the pharmacokinetics and safety profile of prophylactic micafungin in children and adolescents (aged 4 mo to 16 y) undergoing hematopoietic stem cell transplantation. Patients received once-daily doses of either 1 or 1.5 mg/kg micafungin, based on their body weight, for 10 to 14 days. In total, 40 patients received micafungin. Area under the plasma micafungin concentration-time curve was highest in patients aged 6 to 11 years in the 1.5 mg/kg treatment group. Peak plasma micafungin concentration displayed no age-related differences, but was higher in the 1.5 mg/kg versus the 1 mg/kg group. Clearance at steady state by weight and volume of distribution by weight were considerably higher in patients aged 4 months to 5 years. Results from this study show that age and body weight affect micafungin pharmacokinetics in pediatric patients undergoing hematopoietic stem cell transplantation.


Assuntos
Antifúngicos/farmacocinética , Equinocandinas/farmacocinética , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Lipopeptídeos/farmacocinética , Micoses/prevenção & controle , Adolescente , Criança , Pré-Escolar , Equinocandinas/efeitos adversos , Feminino , Humanos , Lipopeptídeos/efeitos adversos , Masculino , Micafungina
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