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1.
Soft Matter ; 20(12): 2840-2862, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38456335

RESUMO

The present article deals with the electrohydrodynamic motion of diffuse porous particles governed by an applied DC electric field. The spatial distribution of monomers as well as the charge distribution across the particle are considered to follow sigmoidal distribution involving decay length. Such a parameter measures the degree of inhomogeneity of the monomer distribution across the particle. The diffuse porous particles resemble several colloidal entities which are often seen in the environment as well as in biological and pharmaceutical industries. Considering the impact of bulk pH and ion steric effects, we modelled the electrohydrodynamics of such porous particulates based on the modified Boltzmann distribution for the spatial distribution of electrolyte ions and the Poisson equation for electric potential as well as the conservation of mass and momentum principles. We adopt regular perturbation analysis with weak field assumption and the perturbed equations are solved numerically to calculate the electrophoretic mobility and neutralization fraction of the particle charge during its motion as well as fluid collection efficiency. We further deduced the closed form relation between the drag force experienced by the charged porous particle and the fluid collection efficiency. In addition to the numerical results, we further derived the closed form analytical results for all the intrinsic parameters indicated above derived within the Debye-Hückel electrostatic framework and homogeneous distribution of monomers within the particle for which the decay length vanishes. The deduced mathematical results as indicated above will be useful to analyze several electrostatic and hydrodynamic features of a wide class of porous particulate and environmental entities.

2.
Ann Oncol ; 31(8): 1030-1039, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32339648

RESUMO

BACKGROUND: The phase 3 JAVELIN Renal 101 trial (NCT02684006) demonstrated significantly improved progression-free survival (PFS) with first-line avelumab plus axitinib versus sunitinib in advanced renal cell carcinoma (aRCC). We report updated efficacy data from the second interim analysis. PATIENTS AND METHODS: Treatment-naive patients with aRCC were randomized (1 : 1) to receive avelumab (10 mg/kg) intravenously every 2 weeks plus axitinib (5 mg) orally twice daily or sunitinib (50 mg) orally once daily for 4 weeks (6-week cycle). The two independent primary end points were PFS and overall survival (OS) among patients with programmed death ligand 1-positive (PD-L1+) tumors. Key secondary end points were OS and PFS in the overall population. RESULTS: Of 886 patients, 442 were randomized to the avelumab plus axitinib arm and 444 to the sunitinib arm; 270 and 290 had PD-L1+ tumors, respectively. After a minimum follow-up of 13 months (data cut-off 28 January 2019), PFS was significantly longer in the avelumab plus axitinib arm than in the sunitinib arm {PD-L1+ population: hazard ratio (HR) 0.62 [95% confidence interval (CI) 0.490-0.777]}; one-sided P < 0.0001; median 13.8 (95% CI 10.1-20.7) versus 7.0 months (95% CI 5.7-9.6); overall population: HR 0.69 (95% CI 0.574-0.825); one-sided P < 0.0001; median 13.3 (95% CI 11.1-15.3) versus 8.0 months (95% CI 6.7-9.8)]. OS data were immature [PD-L1+ population: HR 0.828 (95% CI 0.596-1.151); one-sided P = 0.1301; overall population: HR 0.796 (95% CI 0.616-1.027); one-sided P = 0.0392]. CONCLUSION: Among patients with previously untreated aRCC, treatment with avelumab plus axitinib continued to result in a statistically significant improvement in PFS versus sunitinib; OS data were still immature. CLINICAL TRIAL NUMBER: NCT02684006.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Anticorpos Monoclonais Humanizados , Axitinibe , Carcinoma de Células Renais/tratamento farmacológico , Humanos , Neoplasias Renais/tratamento farmacológico , Sunitinibe/uso terapêutico
4.
Environ Monit Assess ; 187(1): 4148, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25446718

RESUMO

The presence of potentially toxic elements in lignite and coal is a matter of global concern during energy extraction from them. Accordingly, Barsingsar lignite from Rajasthan (India), a newly identified and currently exploited commercial source of energy, was evaluated for the presence of these elements and their fate during its combustion. Mobility of these elements in Barsingsar lignite and its ashes from a power plant (Bikaner-Nagaur region of Thar Desert, India) is presented in this paper. Kaolinite, quartz, and gypsum are the main minerals in lignite. Both the fly ash and bottom ash of lignite belong to class-F with SiO2 > Al2O3 > CaO > MgO. Both the ashes contain quartz, mullite, anhydrite, and albite. As, In, and Sr have higher concentration in the feed than the ashes. Compared to the feed lignite, Ba, Co, U, Cu, Cd, and Ni are enriched (10-5 times) in fly ash and Co, Pb, Li, Ga, Cd, and U in bottom ash (9-5 times). Earth crust-normalization pattern showed enrichment of Ga, U, B, Ag, Cd, and Se in the lignite; Li, Ba, Ga, B, Cu, Ag, Cd, Hg, Pb, and Se, in fly ash; and Li, Sr, Ga, U, B, Cu, Ag, Cd, Pb, and Se in bottom ash. Hg, Ag, Zn, Ni, Ba, and Se are possibly associated with pyrite. Leaching test by toxicity characteristic leaching procedure (TCLP) showed that except B all the elements are within the safe limits prescribed by Indian Standards.


Assuntos
Carvão Mineral/análise , Centrais Elétricas , Oligoelementos/análise , Cinza de Carvão/análise , Cinza de Carvão/química , Cinza de Carvão/toxicidade , Monitoramento Ambiental , Índia , Minerais/análise , Minerais/química , Minerais/toxicidade , Oligoelementos/toxicidade
5.
Br J Cancer ; 110(8): 1917-22, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24691425

RESUMO

BACKGROUND: Limited data exist on outcomes for metastatic renal cell carcinoma (mRCC) patients treated with multiple lines of therapy. Benchmarks for survival are required for patient counselling and clinical trial design. METHODS: Outcomes of mRCC patients from the International mRCC Database Consortium database treated with 1, 2, or 3+ lines of targeted therapy (TT) were compared by proportional hazards regression. Overall survival (OS) and progression-free survival (PFS) were calculated using different population inclusion criteria. RESULTS: In total, 2705 patients were treated with TT of which 57% received only first-line TT, 27% received two lines of TT, and 16% received 3+ lines of TT. Overall survival of patients who received 1, 2, or 3+ lines of TT were 14.9, 21.0, and 39.2 months, respectively, from first-line TT (P<0.0001). On multivariable analysis, 2 lines and 3+ lines of therapy were each associated with better OS (HR=0.738 and 0.626, P<0.0001). Survival outcomes for the subgroups were as follows: for all patients, OS 20.9 months and PFS 7.2 months; for those similar to eligible patients in the first-line ADAPT trial, OS 14.7 months and PFS 5.6 months; for those similar to patients in first-line TIVO-1 trial, OS 24.8 months and PFS 8.2 months; for those similar to patients in second-line INTORSECT trial, OS 13.0 months and PFS 3.9 months; and for those similar to patients in the third-line GOLD trial, OS 18.0 months and PFS 4.4 months. CONCLUSIONS: Patients who are able to receive more lines of TT live longer. Survival benchmarks provide context and perspective when interpreting and designing clinical trials.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Terapia de Alvo Molecular , Serina-Treonina Quinases TOR/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Carcinoma de Células Renais/patologia , Ensaios Clínicos como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Modelos de Riscos Proporcionais , Análise de Sobrevida , Resultado do Tratamento
6.
Ann Oncol ; 25(8): 1603-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24827131

RESUMO

BACKGROUND: Cabozantinib targets tyrosine kinases including the hepatocyte growth factor receptor (MET) and vascular endothelial growth factor (VEGF) receptor 2, which are important drug targets in renal cell carcinoma (RCC). PATIENTS AND METHODS: This single-arm open-label phase I trial evaluated the safety and tolerability of cabozantinib in heavily pretreated patients with metastatic clear cell RCC. RESULTS: The study enrolled 25 RCC patients for whom standard therapy had failed. Patients received a median of two prior systemic agents, and most patients had previously received at least one VEGF pathway inhibiting therapy (22 patients [88%]). Common adverse events included fatigue, diarrhea, nausea, proteinuria, appetite decreased, palmar-plantar erythrodysesthesia, and vomiting. Partial response was reported in seven patients (28%). Median progression-free survival was 12.9 months, and median overall survival was 15.0 months. CONCLUSION: Cabozantinib demonstrates preliminary anti-tumor activity and a safety profile similar to that seen with other multitargeted VEGFR tyrosine kinase inhibitors in advanced RCC patients. Further evaluation of cabozantinib in RCC is warranted. ClinicalTrials.gov identifier: NCT01100619.


Assuntos
Anilidas/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Piridinas/uso terapêutico , Adulto , Idoso , Carcinoma de Células Renais/patologia , Feminino , Seguimentos , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos
7.
Ann Oncol ; 25(1): 149-54, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24356626

RESUMO

BACKGROUND: Targeted therapies in metastatic renal cell carcinoma (mRCC) have been approved based on registration clinical trials that have strict eligibility criteria. The clinical outcomes of patients treated with targeted agents but are ineligible for trials are unknown. PATIENTS AND METHODS: mRCC patients treated with vascular endothelial growth factor-targeted therapy were retrospectively deemed ineligible for clinical trials (according to commonly used inclusion/exclusion criteria) if they had a Karnofsky performance status (KPS) <70%, nonclear-cell histology, brain metastases, hemoglobin ≤9 g/dl, creatinine >2× the upper limit of normal, corrected calcium ≥12 mg/dl, platelet count of <100 × 10(3)/uL, or neutrophil count <1500/mm(3). RESULTS: Overall, 768 of 2210 (35%) patients in the International Metastatic RCC Database Consortium (IMDC) were deemed ineligible for clinical trials by the above criteria. Between ineligible versus eligible patients, the response rate, median progression-free survival (PFS) and median overall survival of first-line targeted therapy were 22% versus 29% (P = 0.0005), 5.2 versus 8.6 months, and 12.5 versus 28.4 months (both P < 0.0001), respectively. Second-line PFS (if applicable) was 2.8 months in the trial ineligible versus 4.3 months in the trial eligible patients (P = 0.0039). When adjusted by the IMDC prognostic categories, the HR for death between trial ineligible and trial eligible patients was 1.55 (95% confidence interval 1.378-1.751, P < 0.0001). CONCLUSIONS: The number of patients that are ineligible for clinical trials is substantial and their outcomes are inferior. Specific trials addressing the unmet needs of protocol ineligible patients are warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/secundário , Ensaios Clínicos como Assunto , Intervalo Livre de Doença , Definição da Elegibilidade , Humanos , Indazóis , Indóis/administração & dosagem , Estimativa de Kaplan-Meier , Avaliação de Estado de Karnofsky , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Niacinamida/administração & dosagem , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Pirimidinas/administração & dosagem , Pirróis/administração & dosagem , Sorafenibe , Sulfonamidas/administração & dosagem , Sunitinibe , Resultado do Tratamento
8.
ESMO Open ; 9(7): 103606, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38901174

RESUMO

BACKGROUND: Lymphocytes are closely linked to mechanisms of action of immuno-oncology (IO) agents. We aimed to assess the prognostic significance of absolute lymphocyte count (ALC) in patients with metastatic renal cell carcinoma (mRCC). PATIENTS AND METHODS: Using the International mRCC Database Consortium (IMDC), patients receiving first-line IO-based combination therapy were analysed. Baseline patient characteristics, objective response rates (ORRs), time to next treatment (TTNT), and overall survival (OS) were compared. RESULTS: Of 966 patients included, 195 (20%) had lymphopenia at baseline, and they had a lower ORR (37% versus 45%; P < 0.001), shorter TTNT (10.1 months versus 24.3 months; P < 0.001), and shorter OS (30.4 months versus 48.2 months; P < 0.001). Among 125 patients with lymphopenia at baseline, 52 (42%) experienced ALC recovery at 3 months, and they had longer OS (not reached versus 30.4 months; P = 0.012). On multivariable analysis for OS, lymphopenia was an independent adverse prognostic factor (hazard ratio 1.68; P < 0.001). Incorporation of lymphopenia into the IMDC criteria improved OS prediction accuracy (C-index from 0.688 to 0.707). CONCLUSIONS: Lymphopenia was observed in one-fifth of treatment-naive patients with mRCC and may serve as an indicator of unfavourable oncologic outcomes in the contemporary IO era.


Assuntos
Carcinoma de Células Renais , Imunoterapia , Neoplasias Renais , Humanos , Carcinoma de Células Renais/terapia , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Masculino , Neoplasias Renais/patologia , Neoplasias Renais/imunologia , Neoplasias Renais/terapia , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/mortalidade , Feminino , Pessoa de Meia-Idade , Prognóstico , Contagem de Linfócitos , Idoso , Imunoterapia/métodos , Linfopenia , Estudos Retrospectivos , Bases de Dados Factuais , Adulto
10.
J Chem Phys ; 138(12): 124501, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23556730

RESUMO

Ultrafast deep-ultraviolet through near infrared (210-950 nm) transient absorption spectroscopy complemented by ab initio multiconfigurational calculations offers a global description of the photochemical reaction pathways of bromoform following 255-nm excitation in methylcyclohexane and acetonitrile solutions. Photoexcitation of CHBr3 leads to the ground-state iso-CHBr3 product in a large quantum yield (∼35%), formed through two different mechanisms: concerted excited-state isomerization and cage-induced isomerization through the recombination of the nascent radical pair. These two processes take place on different time scales of tens of femtoseconds and several picoseconds, respectively. The novel ultrafast direct isomerization pathway proposed herein is consistent with the occurrence of a conical intersection between the first excited singlet state of CHBr3 and the ground electronic state of iso-CHBr3. Complete active space self-consistent field calculations characterize this singularity in the vicinity of a second order saddle point on the ground state which connects the two isomer forms. For cage-induced isomerization, both the formation of the nascent radical pair and its subsequent collapse into ground-state iso-CHBr3 are directly monitored through the deep-ultraviolet absorption signatures of the radical species. In both mechanisms, the optically active (i.e., those with largest Franck-Condon factors) C-Br-Br bending and Br-Br stretching modes of ground-state iso-CHBr3 have the largest projection on the reaction coordinate, enabling us to trace the structural changes accompanying vibrational relaxation of the non-equilibrated isomers through transient absorption dynamics. The iso-CHBr3 photoproduct is stable in methylcyclohexane, but undergoes either facile thermal isomerization to the parent CHBr3 structure through a cyclic transition state stabilized by the polar acetonitrile medium (∼300-ps lifetime), and hydrolysis in the presence of water.


Assuntos
Teoria Quântica , Raios Ultravioleta , Processos Fotoquímicos , Espectroscopia de Luz Próxima ao Infravermelho , Trialometanos/química
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