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2.
ESMO Open ; 6(2): 100043, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33610123

RESUMO

BACKGROUND: Cediranib, an oral anti-angiogenic VEGFR 1-3 inhibitor, was studied at a daily dose of 20 mg in combination with platinum-based chemotherapy and as maintenance in a randomised trial in patients with first relapse of 'platinum-sensitive' ovarian cancer and has been shown to improve progression-free survival (PFS). PATIENTS AND METHODS: ICON6 (NCT00532194) was an international three-arm, double-blind, placebo-controlled randomised trial. Between December 2007 and December 2011, 456 women were randomised, using stratification, to receive either chemotherapy with placebo throughout (arm A, reference); chemotherapy with concurrent cediranib, followed by maintenance placebo (arm B, concurrent); or chemotherapy with concurrent cediranib, followed by maintenance cediranib (arm C, maintenance). Due to an enforced redesign of the trial in September 2011, the primary endpoint became PFS between arms A and C which we have previously published, and the overall survival (OS) was defined as a secondary endpoint, which is reported here. RESULTS: After a median follow-up of 25.6 months, strong evidence of an effect of concurrent plus maintenance cediranib on PFS was observed [hazard ratio (HR) 0.56, 95% confidence interval (CI) 0.44-0.72, P < 0.0001]. In this final update of the survival analysis, 90% of patients have died. There was a 7.4-month difference in median survival and an HR of 0.86 (95% CI: 0.67-1.11, P = 0.24) in favour of arm C. There was strong evidence of a departure from the assumption of non-proportionality using the Grambsch-Therneau test (P = 0.0031), making the HR difficult to interpret. Consequently, the restricted mean survival time (RMST) was used and the estimated difference over 6 years by the RMST was 4.8 months (95% CI: -0.09 to 9.74 months). CONCLUSIONS: Although a statistically significant difference in time to progression was seen, the enforced curtailment in recruitment meant that the secondary analysis of OS was underpowered. The relative reduction in the risk of death of 14% risk of death was not conventionally statistically significant, but this improvement and the increase in the mean survival time in this analysis suggest that cediranib may have worthwhile activity in the treatment of recurrent ovarian cancer and that further research should be undertaken.


Assuntos
Neoplasias Ovarianas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Quinazolinas/uso terapêutico
3.
Int J Radiat Oncol Biol Phys ; 99(1): 51-60, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28816160

RESUMO

PURPOSE: The heart receives high radiation doses during radiation therapy of advanced-stage lung cancer. We have explored associations between overall survival, cardiac radiation doses, and electrocardiographic (ECG) changes in patients treated in IDEAL-CRT, a trial of isotoxically escalated concurrent chemoradiation delivering tumor doses of 63 to 73 Gy. METHODS AND MATERIALS: Dosimetric and survival data were analyzed for 78 patients. The whole heart, pericardium, AV node, and walls of left and right atria (LA/RA-Wall) and ventricles (LV/RV-Wall) were outlined on radiation therapy planning scans, and differential dose-volume histograms (dDVHs) were calculated. For each structure, dDVHs were approximated using the average dDVH and the 10 highest-ranked structure-specific principal components (PCs). ECGs at baseline and 6 months after radiation therapy were analyzed for 53 patients, dichotomizing patients according to presence or absence of "any ECG change" (conduction or ischemic/pericarditis-like change). All-cause death rate (DR) was analyzed from the start of treatment using Cox regression. RESULTS: 38% of patients had ECG changes at 6 months. On univariable analysis, higher scores for LA-Wall-PC6, Heart-PC6, "any ECG change," and larger planning target volume (PTV) were significantly associated with higher DR (P=.003, .009, .029, and .037, respectively). Heart-PC6 and LA-Wall-PC6 represent larger volumes of whole heart and left atrial wall receiving 63 to 69 Gy. Cardiac doses ≥63 Gy were concentrated in the LA-Wall, and consequently Heart-PC6 was highly correlated with LA-Wall-PC6. "Any ECG change," LA-Wall-PC6 scores, and PTV size were retained in the multivariable model. CONCLUSIONS: We found associations between higher DR and conduction or ischemic/pericarditis-like changes on ECG at 6 months, and between higher DR and higher Heart-PC6 or LA-Wall-PC6 scores, which are closely related to heart or left atrial wall volumes receiving 63 to 69 Gy in this small cohort of patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Coração/efeitos da radiação , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/radioterapia , Órgãos em Risco/efeitos da radiação , Lesões por Radiação/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Causas de Morte , Fracionamento da Dose de Radiação , Eletrocardiografia/efeitos da radiação , Feminino , Coração/diagnóstico por imagem , Coração/fisiologia , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/efeitos da radiação , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Órgãos em Risco/diagnóstico por imagem , Órgãos em Risco/fisiologia , Pericárdio/efeitos da radiação , Análise de Componente Principal , Estudos Prospectivos , Doses de Radiação , Lesões por Radiação/fisiopatologia , Planejamento da Radioterapia Assistida por Computador
4.
Methods Enzymol ; 574: 331-354, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27423867

RESUMO

Characterizing the dynamic behavior of nucleosomes in the central nervous system is vital to our understanding of brain-specific chromatin-templated processes and their roles in transcriptional plasticity. Histone turnover-the complete loss of old, and replacement by new, nucleosomal histones-is one such phenomenon that has recently been shown to be critical for cell-type-specific transcription in brain, synaptic plasticity, and cognition. Such revelations that histones, long believed to static proteins in postmitotic cells, are highly dynamic in neurons were only possible owing to significant advances in analytical chemistry-based techniques, which now provide a platform for investigations of histone dynamics in both healthy and diseased tissues. Here, we discuss both past and present proteomic methods (eg, mass spectrometry, human "bomb pulse labeling") for investigating histone turnover in brain with the hope that such information may stimulate future investigations of both adaptive and aberrant forms of "neuroepigenetic" plasticity.


Assuntos
Encéfalo/metabolismo , Histonas/metabolismo , Espectrometria de Massas/métodos , Proteômica/métodos , Sequência de Aminoácidos , Animais , Autopsia/métodos , Química Encefálica , Histonas/análise , Humanos
5.
Lancet ; 364(9448): 1865-71, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15555666

RESUMO

BACKGROUND: No trials of co-trimoxazole (trimethoprim-sulfamethoxazole) prophylaxis for HIV-infected adults or children have been done in areas with high levels of bacterial resistance to this antibiotic. We aimed to assess the efficacy of daily co-trimoxazole in such an area. METHODS: We did a double-blind randomised placebo-controlled trial in children aged 1-14 years with clinical features of HIV infection in Zambia. Primary outcomes were mortality and adverse events possibly related to treatment. Analysis was by intention to treat. FINDINGS: In October, 2003, the data and safety monitoring committee recommended early stopping of the trial. 541 children had been randomly assigned; seven were subsequently identified as HIV negative and excluded. After median follow-up of 19 months, 74 (28%) children in the co-trimoxazole group and 112 (42%) in the placebo group had died (hazard ratio [HR] 0.57 [95% CI 0.43-0.77], p=0.0002). This benefit applied in children followed up beyond 12 months (n=320, HR 0.48 [0.27-0.84], test for heterogeneity p=0.60) and across all ages (test for heterogeneity p=0.82) and baseline CD4 counts (test for heterogeneity p=0.36). 16 (6%) children in the co-trimoxazole group had grade 3 or 4 adverse events compared with 18 (7%) in the placebo group. These events included rash (one placebo), and a neutrophil count on one occasion less than 0.5x10(9)/L (16 [6%] co-trimoxazole vs seven [3%] placebo, p=0.06). Pneumocystis carinii was identified by immunofluorescence in only one (placebo) of 73 nasopharyngeal aspirates from children with pneumonia. INTERPRETATION: Our results suggest that children of all ages with clinical features of HIV infection should receive co-trimoxazole prophylaxis in resource-poor settings, irrespective of local resistance to this drug.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Antibacterianos/efeitos adversos , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Infecções por HIV/mortalidade , Hospitalização , Humanos , Lactente , Masculino , Taxa de Sobrevida , Combinação Trimetoprima e Sulfametoxazol/efeitos adversos , Zâmbia
6.
BMJ ; 327(7422): 1019, 2003 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-14593035

RESUMO

OBJECTIVE: To describe changes in demographic factors, disease progression, hospital admissions, and use of antiretroviral therapy in children with HIV. DESIGN: Active surveillance through the national study of HIV in pregnancy and childhood (NSHPC) and additional data from a subset of children in the collaborative HIV paediatric study (CHIPS). SETTING: United Kingdom and Ireland. PARTICIPANTS: 944 children with perinatally acquired HIV-1 under clinical care. MAIN OUTCOME MEASURES: Changes over time in progression to AIDS and death, hospital admission rates, and use of antiretroviral therapy. RESULTS: 944 children with perinatally acquired HIV were reported in the United Kingdom and Ireland by October 2002; 628 (67%) were black African, 205 (22%) were aged > or = 10 years at last follow up, 193 (20%) are known to have died. The proportion of children presenting who were born abroad increased from 20% in 1994-5 to 60% during 2000-2. Mortality was stable before 1997 at 9.3 per 100 child years at risk but fell to 2.0 in 2001-2 (trend P < 0.001). Progression to AIDS also declined (P < 0.001). From 1997 onwards the proportion of children on three or four drug antiretroviral therapy increased. Hospital admission rates declined by 80%, but with more children in follow up the absolute number of admissions fell by only 26%. CONCLUSION: In children with HIV infection, mortality, AIDS, and hospital admission rates have declined substantially since the introduction of three or four drug antiretroviral therapy in 1997. As infected children in the United Kingdom and Ireland are living longer, there is an increasing need to address their medical, social, and psychological needs as they enter adolescence and adult life.


Assuntos
Síndrome da Imunodeficiência Adquirida/mortalidade , HIV-1 , Síndrome da Imunodeficiência Adquirida/congênito , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Antirretrovirais/uso terapêutico , Criança , Pré-Escolar , Progressão da Doença , Feminino , Seguimentos , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Irlanda/epidemiologia , Masculino , Mortalidade/tendências , Modelos de Riscos Proporcionais , Fatores de Risco , Taxa de Sobrevida , Reino Unido/epidemiologia
7.
Dev Biol ; 98(1): 117-29, 1983 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6862100

RESUMO

The level of early histone mRNA in Strongylocentrotus purpuratus changes abruptly at 6 hr of development, increasing an average of 10-fold by 9-10.5 hr and then decreasing over 2-fold by 13.5-15 hr. These changes occur when the late embryonic mRNA is still a very minor component of histone gene transcription. The exact values of increase and decrease of mRNA level vary from experiment to experiment and may reflect the conditions of embryos at different times. The instantaneous rate of synthesis of histone RNA per embryo increases from at least 47 fg/min at 6 hr to 114 fg/min at 9 hr and then drops to 29 fg/min at 12 hr. The rate of mRNA accumulation is lower: 20, 43, and 12 fg/min, respectively. On a per cell basis, however, the rate of synthesis and accumulation is highest at 6 hr and continuously decreases to 1/20 the level per cell at 12 hr. The transcriptional rates and relative mRNA increases taken together predict an average increase from 0.16 to 0.24 pg/embryo (6-10 X 10(5) molecules) per mRNA species in the egg to 1.6 to 2.4 pg/embryo (6-10 X 10(6) molecules) at 10.5 hr. The transcription rates indicate that at the maximal values we obtained, about two to three molecules of each histone RNA are made per gene copy per minute. The half-life of the histone mRNAs in the period from 6 to 13.5 hr probably varies, with the maximal turnover at about the time histone RNA level peaks. A half-life of 1.5 hr at 12 hr of development is estimated. Change in transcriptional rate per nucleus, increase in cell number, and probably a change in mRNA stability as well are therefore involved in the control of histone mRNA levels in the early embryo.


Assuntos
Equinodermos/crescimento & desenvolvimento , Histonas/genética , RNA Mensageiro/biossíntese , Trifosfato de Adenosina/metabolismo , Animais , Hibridização de Ácido Nucleico , Fatores de Tempo
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