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1.
J Physiol ; 601(21): 4723-4735, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37768183

RESUMO

Increased amplitude of persistent inward currents (PICs) is observed in pre-symptomatic genetically modified SOD1 mice models of amyotrophic lateral sclerosis (ALS). However, at the symptomatic stage this reverses and there is a large reduction in PIC amplitude. It remains unclear whether these changes in PICs can be observed in humans, with cross-sectional studies in humans reporting contradictory findings. In people with ALS, we estimated the PIC contribution to self-sustained firing of motoneurons, using the paired-motor unit analysis to calculate the Δfrequency (ΔF), to compare the weaker and stronger muscles during the course of disease. We hypothesised that, with disease progression, ΔFs would relatively increase in the stronger muscles; and decline in the weaker muscles. Forty-three individuals with ALS were assessed in two occasions on average 17 weeks apart. Tibialis anterior high-density electromyograms were recorded during dorsiflexion (40% of maximal capacity) ramped contractions, followed by clinical tests. ∆F increased from 3.14 (2.57, 3.71) peaks per second (pps) to 3.55 (2.94, 4.17) pps on the stronger muscles (0.41 (0.041, 0.781) pps, standardised difference (d) = 0.287 (0.023, 0.552), P = 0.030). ∆F reduced from 3.38 (95% CI 2.92, 3.84) pps to 2.88 (2.40, 3.36) pps on the weaker muscles (-0.50 (-0.80, -0.21) pps, d = 0.353 (0.138, 0.567), P = 0.001). The ALSFRS-R score reduced 3.9 (2.3, 5.5) points. These data indicate that the contribution of PICs to motoneuron self-sustained firing increases over time in early stages of the disease when there is little weakness before decreasing as the disease progresses and muscle weakness exacerbates, in alignment with the findings from studies using SOD1 mice. KEY POINTS: Research on mouse model of amyotrophic lateral sclerosis (ALS) suggests that the amplitude of persistent inward currents (PICs) is increased in early stages before decreasing as the disease progresses. Cross-sectional studies in humans have reported contradictory findings with both higher and lower PIC contributions to motoneuron self-sustained firing. In this longitudinal (∼17 weeks) study we tracked changes in PIC contribution to motoneuron self-sustained firing, using the ΔF calculation (i.e. onset-offset hysteresis of motor unit pairs), in tibialis anterior muscles with normal strength and with clinical signs of weakness in people with ALS. ΔFs decreased over time in muscles with clinical signs of weakness. The PIC contribution to motoneuron self-sustained firing increases before the onset of muscle weakness, and subsequently decreases when muscle weakness progresses.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Animais , Camundongos , Estudos Transversais , Superóxido Dismutase-1/genética , Neurônios Motores/fisiologia , Músculo Esquelético , Debilidade Muscular , Paresia , Progressão da Doença
2.
Plant Cell Environ ; 43(3): 662-674, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31759335

RESUMO

Arabidopsis eceriferum (cer) mutants with unique alterations in their rosette leaf cuticular wax accumulation and composition established by gas chromatography have been investigated using attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectroscopy in combination with univariate and multivariate analysis. Objectives of this study were to evaluate the utility of ATR-FTIR for detection of chemical diversity in leaf cuticles, obtain spectral profiles of cer mutants in comparison with the wild type, and identify changes in leaf cuticles caused by drought stress. FTIR spectra revealed both genotype- and treatment-dependent differences in the chemical make-up of Arabidopsis leaf cuticles. Drought stress caused specific changes in the integrated area of the CH3 peak, asymmetrical and symmetrical CH2 peaks, ester carbonyl peak and the peak area ratio of ester CO to CH2 asymmetrical vibration. CH3 peak positively correlated with the total wax accumulation. Thus, ATR-FTIR spectroscopy is a valuable tool that can advance our understanding of the role of cuticle chemistry in plant response to drought and allow selection of superior drought-tolerant varieties from large genetic resources.


Assuntos
Arabidopsis/genética , Folhas de Planta/genética , Ceras/metabolismo , Arabidopsis/fisiologia , Cromatografia Gasosa , Secas , Genótipo , Umidade , Mutação/genética , Filogenia , Análise de Componente Principal , Solo/química , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Fisiológico
3.
J Clin Oncol ; 42(23): 2800-2811, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38838287

RESUMO

PURPOSE: Bempegaldesleukin (BEMPEG) is a pegylated interleukin (IL)-2 cytokine prodrug engineered to provide controlled and sustained activation of the clinically validated IL-2 pathway, with the goal of preferentially activating and expanding effector CD8+ T cells and natural killer cells over immunosuppressive regulator T cells in the tumor microenvironment. The open-label, phase III randomized controlled PIVOT-09 trial investigated the efficacy and safety of BEMPEG plus nivolumab (NIVO) as first-line treatment for advanced/metastatic clear cell renal cell carcinoma (ccRCC) with intermediate-/poor-risk disease. METHODS: Patients with previously untreated advanced/metastatic ccRCC were randomly assigned (1:1) to BEMPEG plus NIVO, or investigator's choice of tyrosine kinase inhibitor (TKI; sunitinib or cabozantinib). Coprimary end points were objective response rate (ORR) by blinded independent central review and overall survival (OS) in patients with International Metastatic RCC Database Consortium (IMDC) intermediate-/poor-risk disease. RESULTS: Overall, 623 patients were randomly assigned to BEMPEG plus NIVO (n = 311) or TKI (n = 312; sunitinib n = 225, cabozantinib n = 87), of whom 514 (82.5%) had IMDC intermediate-/poor-risk disease. In patients with IMDC intermediate-/poor-risk disease, ORR with BEMPEG plus NIVO versus TKI was 23.0% (95% CI, 18.0 to 28.7) versus 30.6% (95% CI, 25.1 to 36.6; difference, -7.7 [95% CI, -15.2 to -0.2]; P = .0489), and median OS was 29.0 months versus not estimable (hazard ratio, 0.82 [95% CI, 0.61 to 1.10]; P = .192), respectively. More frequent all-grade treatment-related adverse events (TRAEs) with BEMPEG plus NIVO versus TKI included pyrexia (32.6% v 2.0%) and pruritus (31.3% v 8.8%). Grade 3/4 TRAEs were less frequent with BEMPEG plus NIVO (25.8%) versus TKI (56.5%). CONCLUSION: First-line BEMPEG plus NIVO for advanced/metastatic ccRCC did not improve efficacy in patients with intermediate-/poor-risk disease but led to fewer grade 3/4 TRAEs versus TKI.


Assuntos
Anilidas , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma de Células Renais , Neoplasias Renais , Nivolumabe , Polietilenoglicóis , Piridinas , Sunitinibe , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Anilidas/administração & dosagem , Anilidas/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Nivolumabe/administração & dosagem , Nivolumabe/uso terapêutico , Nivolumabe/efeitos adversos , Idoso , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Sunitinibe/uso terapêutico , Sunitinibe/administração & dosagem , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Adulto , Interleucina-2/administração & dosagem , Interleucina-2/uso terapêutico , Interleucina-2/efeitos adversos , Interleucina-2/análogos & derivados , Idoso de 80 Anos ou mais
4.
J Transl Med ; 11: 241, 2013 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-24088382

RESUMO

INTRODUCTION: Activation of the PI3K/AKT pathway is a common phenomenon in cancer due to multiple mechanisms, including mutation of PI3KCA, loss or mutation of PTEN, or over-expression of receptor tyrosine kinases. We recently developed a novel AKT kinase inhibitor, AZD5363, and demonstrated that HGC27, a cell line harboring both PI3KCA mutation and PTEN loss, displayed the greatest sensitivity to this AKT inhibitor in vitro and in vivo. CASE PREPARATION: To further elucidate the correlation between AZD5363 response and genetic alterations in gastric cancer (GC) and identify GC patients with both PI3KCA mutations and PTEN loss, we investigated the effects of pharmacological inhibition of AKT on a panel of 20 GC cell lines and genetic aberrations in tumor samples from a cohort of Chinese GC patients. We demonstrated that GC cells with PI3KCA mutations were selectively sensitive to AZD5363. Disease linkage studies showed that PI3KCA activating mutations or PTEN loss were found in 2.7% (4/150) and 23% (14/61) of Chinese GC patients respectively. To further dissect the role of PI3KCA mutation and PTEN loss in response to AKT inhibition, we tested the antitumor activity of AZD5363 in two patient-derived GC xenograft (PDGCX) models harboring either PI3KCA mutation or PTEN loss. Our data indicated that AZD5363 monotherapy treatment led to a moderate response in the PI3KCA mutant PDGCX model. Whilst monotherapy AZD5363 or Taxotere were ineffective in the PTEN negative PDGCX model, significant anti-tumor activity was observed when AZD5363 was combined with Taxotere. CONCLUSION: Our results indicated that PI3KCA mutation is an important determinant of response to AKT inhibition in GC and combination with AZD5363 can overcome innate resistance to Taxotere in a PTEN loss PDGCX model. It is suggested that AKT inhibitor is an attractive option for treatment of a new segment of GC patients with aberrant PI3K/AKT signaling.


Assuntos
Proteínas Nucleares/genética , PTEN Fosfo-Hidrolase/deficiência , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Taxoides/uso terapêutico , Fatores de Transcrição/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Povo Asiático , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , China , Modelos Animais de Doenças , Docetaxel , Feminino , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Nus , Mutação/genética , PTEN Fosfo-Hidrolase/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas/farmacologia , Pirróis/farmacologia , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Taxoides/farmacologia , Resultado do Tratamento
5.
Expert Opin Drug Metab Toxicol ; 19(10): 721-731, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37746740

RESUMO

BACKGROUND: Enhancing the precision of drug-drug interaction (DDI) prediction is essential for improving drug safety and efficacy. The aim is to identify the most effective fraction metabolized by CY3A4 (fm) for improving DDI prediction using physiologically based pharmacokinetic (PBPK) models. RESEARCH DESIGN AND METHODS: The fm values were determined for 33 approved drugs using a human liver microsome for in vitro measurements and the ADMET Predictor software for in silico predictions. Subsequently, these fm values were integrated into PBPK models using the GastroPlus platform. The PBPK models, combined with a ketoconazole model, were utilized to predict AUCR (AUCcombo with ketoconazole/AUCdosing alone), and the accuracy of these predictions was evaluated by comparison with observed AUCR. RESULTS: The integration of in vitro fm method demonstrates superior performance compared to the in silico fm method and fm of 100% method. Under the Guest-limits criteria, the integration of in vitro fm achieves an accuracy of 76%, while the in silico fm and fm of 100% methods achieve accuracies of 67% and 58%, respectively. CONCLUSIONS: Our study highlights the importance of in vitro fm data to improve the accuracy of predicting DDIs and demonstrates the promising potential of in silico fm in predicting DDIs.


Assuntos
Citocromo P-450 CYP3A , Cetoconazol , Humanos , Citocromo P-450 CYP3A/metabolismo , Cetoconazol/metabolismo , Modelos Biológicos , Interações Medicamentosas , Microssomos Hepáticos/metabolismo , Simulação por Computador
6.
Epidemics ; 42: 100662, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36563470

RESUMO

The COVID-19 pandemic has provided stiff challenges for planning and resourcing in health services in the UK and worldwide. Epidemiological models can provide simulations of how infectious disease might progress in a population given certain parameters. We adapted an agent-based model of COVID-19 to inform planning and decision-making within a healthcare setting, and created a software framework that automates processes for calibrating the model parameters to health data and allows the model to be run at national population scale on National Health Service (NHS) infrastructure. We developed a method for calibrating the model to three daily data streams (hospital admissions, intensive care occupancy, and deaths), and demonstrate that on cross-validation the model fits acceptably to unseen data streams including official estimates of COVID-19 incidence. Once calibrated, we use the model to simulate future scenarios of the spread of COVID-19 in England and show that the simulations provide useful projections of future COVID-19 clinical demand. These simulations were used to support operational planning in the NHS in England, and we present the example of the use of these simulations in projecting future clinical demand during the rollout of the national COVID-19 vaccination programme. Being able to investigate uncertainty and test sensitivities was particularly important to the operational planning team. This epidemiological model operates within an ecosystem of data technologies, drawing on a range of NHS, government and academic data sources, and provides results to strategists, planners and downstream data systems. We discuss the data resources that enabled this work and the data challenges that were faced.


Assuntos
COVID-19 , Humanos , Medicina Estatal , Pandemias , Vacinas contra COVID-19 , Calibragem , Ecossistema , Atenção à Saúde
7.
Eur Urol ; 82(4): 365-373, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35643589

RESUMO

BACKGROUND: Despite recent changes in the treatment landscape, there remains an unmet need for effective, tolerable, chemotherapy-free treatments for patients with advanced/metastatic urothelial carcinoma (mUC), especially cisplatin-ineligible patients. OBJECTIVE: To evaluate the immunostimulatory interleukin-2 cytokine prodrug bempegaldesleukin (BEMPEG) plus nivolumab in patients with advanced/mUC from the phase 2 multicenter PIVOT-02 study. DESIGN, SETTING, AND PARTICIPANTS: This open-label, multicohort phase 1/2 study enrolled patients with previously untreated locally advanced/surgically unresectable or mUC (N = 41). INTERVENTION: Patients received BEMPEG 0.006 mg/kg plus nivolumab 360 mg intravenously every 3 wk. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary objectives were safety and the objective response rate (ORR) in patients with measurable disease at baseline and at least one postbaseline tumor response assessment (response-evaluable). Secondary objectives were overall survival (OS) and progression-free survival (PFS). Exploratory biomarker analyses via univariate logistic regression were performed to test the association between potential biomarkers (CD8+ tumor-infiltrating lymphocytes, tumor mutational burden, and IFN-γ gene expression profile) and response. RESULTS AND LIMITATIONS: The ORR was 35% (13/37 evaluable patients) and the complete response rate was 19% (7/37 patients); the median duration of response was not reached. Median PFS was 4.1 mo (95% confidence interval [CI] 2.1-8.7) and median OS was 23.7 mo (95% CI 15.8-not reached). Overall, 40/41 patients (98%) experienced at least one treatment-related adverse event (TRAE); grade 3/4 TRAEs occurred in 11 patients (27%), most commonly pyrexia (4.9%; 2 patients). Exploratory biomarker analyses showed no association between biomarkers and response. Limitations include the small sample size and single-arm design. CONCLUSIONS: BEMPEG plus nivolumab was well tolerated and showed antitumor activity as first-line treatment in patients with locally advanced/mUC. PATIENT SUMMARY: We investigated an immune-stimulating prodrug called bempegaldesleukin plus the antibody nivolumab as the first therapy for patients with advanced or metastatic cancer of the urinary tract. This combination had manageable treatment-related side effects and was effective in a subset of patients. This trial is registered at ClinicalTrials.gov as NCT02983045.


Assuntos
Carcinoma de Células de Transição , Pró-Fármacos , Neoplasias da Bexiga Urinária , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/secundário , Humanos , Interleucina-2/uso terapêutico , Nivolumabe/efeitos adversos , Pró-Fármacos/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/etiologia
8.
J Immunother Cancer ; 10(4)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35444058

RESUMO

BACKGROUND: Immune checkpoint inhibitor-based combinations have expanded the treatment options for patients with renal cell carcinoma (RCC); however, tolerability remains challenging. The aim of this study was to evaluate the safety and efficacy of the immunostimulatory interleukin-2 cytokine prodrug bempegaldesleukin (BEMPEG) plus nivolumab (NIVO) as first-line therapy in patients with advanced clear-cell RCC. METHODS: This was an open-label multicohort, multicenter, single-arm phase 1/2 study; here, we report results from the phase 1/2 first-line RCC cohort (N=49). Patients received BEMPEG 0.006 mg/kg plus NIVO 360 mg intravenously every 3 weeks. The primary objectives were safety and objective response rate (ORR; patients with measurable disease at baseline and at least one postbaseline tumor response assessment). Secondary objectives included overall survival (OS) and progression-free survival (PFS). Exploratory biomarker analyses: association between baseline biomarkers and ORR. RESULTS: At a median follow-up of 32.7 months, the ORR was 34.7% (17/49 patients); 3/49 patients (6.1%) had a complete response. Of the 17 patients with response, 14 remained in response for >6 months, and 6 remained in response for >24 months. Median PFS was 7.7 months (95% CI 3.8 to 13.9), and median OS was not reached (95% CI 37.3 to not reached). Ninety-eight per cent (48/49) of patients experienced ≥1 treatment-related adverse event (TRAE) and 38.8% (19/49) had grade 3/4 TRAEs, most commonly syncope (8.2%; 4/49) and increased lipase (6.1%; 3/49). No association between exploratory biomarkers and ORR was observed. Limitations include the small sample size and single-arm design. CONCLUSIONS: BEMPEG plus NIVO showed preliminary antitumor activity as first-line therapy in patients with advanced clear-cell RCC and was well tolerated. These findings warrant further investigation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma de Células Renais , Neoplasias Renais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Feminino , Humanos , Interleucina-2/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Masculino , Nivolumabe/uso terapêutico
9.
AAPS J ; 24(1): 12, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34893925

RESUMO

The prediction of drug-drug interactions (DDIs) plays critical roles for the estimation of DDI risk caused by inhibition of CYP3A4. The aim of this paper is to develop a physiologically based pharmacokinetic (PBPK)-DDI model for prediction of the DDI co-administrated with ketoconazole in humans and evaluate the predictive performance of the model. The pharmacokinetic and biopharmaceutical properties of 35 approved drugs, as victims, were collected for the development of a PBPK model, which were linked to the PBPK model of ketoconazole for the DDI prediction. The PBPK model of victims and ketoconazole were validated by matching actual in vivo pharmacokinetic data. The predicted results of DDI were compared with actual data to evaluate the predictive performance. The percentage of predicted ratio of AUC (AUCR), Cmax (CmaxR), and Tmax (TmaxR) was 75%, 69%, and 91%, respectively, which were within the twofold threshold (range, 0.5-2.0×) of the observed values. Only 3% of the predicted AUCRs are obviously underestimated. After integration of the reported fraction of metabolism (fm) into the PBPK-DDI model for limited four cases, the model-predicted AUCRs were improved from the twofold range of the observed AUCRs to the 90% confidence interval. The developed method could reasonably predict drug-drug interaction with a low risk of underestimation. The present accuracy of the prediction was improved compared with that of static mechanistic models. The evaluation of predictive performance increases the confidence using the model to evaluate the risk of DDIs co-administrated with ketoconazole before the in vivo DDI study.


Assuntos
Inibidores do Citocromo P-450 CYP3A , Citocromo P-450 CYP3A , Cetoconazol , Área Sob a Curva , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/farmacocinética , Interações Medicamentosas , Humanos , Cetoconazol/farmacocinética , Modelos Químicos
10.
Artigo em Inglês | MEDLINE | ID: mdl-34360452

RESUMO

The purpose of this study was to learn about mothers' experiences with food choices for their pre-school children in underprivileged communities in Greater Western Sydney (GWS). A total of 20 mother-child dyads living in GWS were recruited to a qualitative study from an ongoing birth cohort study. Participants' houses were visited for semi-structured interviews, which were recorded, transcribed verbatim, and analysed thematically. The interviews yielded five main themes: (i) food choices, nutrition, and health; (ii) accessibility and availability of foods (iii) buying time for parents; (iv) child's age and their preference on food choices; (v) conditioning certain behaviours by family and cultural factors. Nutrition literacy, child's preferences, unhealthy food intake by family members, child's demand, advertising and availability of harmful foods, and time constraints were all mentioned as hurdles to mothers making appropriate meal choices for their children. However, some identified facilitators were promoting parents' knowledge, increasing access to health educational materials, upskilling mothers to providing healthier alternatives, regulating the marketing of unhealth foods. Although, the present study identified critical factors that influence mothers' food choices for their young children, making healthy food choices is a complex practice as it is shaped by individual, social and environmental influences.


Assuntos
Mães , Saúde Bucal , Criança , Pré-Escolar , Estudos de Coortes , Dieta , Comportamento Alimentar , Feminino , Preferências Alimentares , Conhecimentos, Atitudes e Prática em Saúde , Humanos
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