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1.
Eur J Cancer ; 94: 70-78, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29544162

RESUMO

The fracture impact of adjuvant bisphosphonates in breast cancer is not defined with most trials reporting changes in bone mineral density as a surrogate. The AZURE trial (ISRCTN79831382) evaluated the impact of adjuvant zoledronic acid (ZOL) on fractures. The AZURE trial is an academic, multi-centre, randomised phase III study evaluating the addition of ZOL 4 mg to standard therapy (neo/adjuvant chemotherapy and/or endocrine therapy) for 5 years (administered by intravenous (iv) infusion every 3-4 weeks for 6 doses, then 3 monthly × 8 and 6 monthly × 5) in patients with stage II/III early breast cancer. Fracture data collected as part of skeletal-related adverse event reporting were analysed after a median of 84.2 months of follow-up and 966 disease-free survival (DFS) events. We assessed number of fractures, time-to-first fracture and the incidence of fractures before and after disease recurrence. Two hundred forty-four patients reported ≥1 fracture, 140 (8.3%) in the control arm (171 fractures) and 104 (6.2%) in the ZOL arm (120 fractures). Of the 291 fractures reported, 207 fractures occurred in the absence of recurrence (control 111, ZOL 96), 80 after recurrence (control 59, ZOL 21). The 5-year fracture rate was reduced from 5.9% (95%CI 4.8, 7.1%; control) to 3.8% (95%CI 2.9, 4.7%) with ZOL. ZOL significantly increased time-to-first fracture (HR 0.69, 95%CI 0.53-0.90; P = 0.0053) but the majority of fracture prevention benefit occurred after a DFS event (HR 0.3; 95%CI 0.17, 0.53; P < 0.001). Fracture benefits from ZOL were similar across menopausal sub-groups. In conclusion, adjuvant ZOL reduced the risk of clinical fractures, the majority of this protection occurred after disease recurrence.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Neoplasias da Mama/complicações , Fraturas Ósseas/prevenção & controle , Ácido Zoledrônico/uso terapêutico , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante , Feminino , Fraturas Ósseas/epidemiologia , Humanos , Incidência , Pessoa de Meia-Idade
3.
Artigo em Inglês | MEDLINE | ID: mdl-27965826

RESUMO

BACKGROUND: Stage I non-small cell lung cancer (NSCLC) is potentially curable, and surgery is considered to be the standard of care for patients with good performance status and minimal co-morbidity. However, a significant proportion of patients with stage I NSCLC have a poorer performance status and significant medical co-morbidity that make them at higher risk of morbidity and mortality from surgery. Stereotactic ablative radiotherapy (SABR), which uses modern radiotherapeutic techniques to deliver large doses of radiation, has shown superiority over conventional radiotherapy in terms of local control and toxicity and is a standard of care for patients with stage I NSCLC who are at too high risk for surgery. However, it is not known whether surgery or SABR is the most effective in patients with stage I NSCLC who are suitable for surgery but are less fit and at higher risk surgical complications. Previous randomised studies have failed to recruit in this setting, and therefore, a feasibility study is required to see whether a full randomised control trial would be possible. METHODS/DESIGN: SABRTooth is a UK-based, multi-centre, open-label, two-group individually (1:1) randomised controlled feasibility study in patients with peripheral stage I NSCLC considered to be at higher risk from surgical resection. The study will assess the feasibility of conducting a definitive large-scale phase III trial. The primary objective is to assess recruitment rates to provide evidence that, when scaled up, recruitment to a large phase III trial would be possible; the target recruitment being 54 patients in total, over a 21-month period. There are multiple secondary and exploratory objectives designed to explore the optimum recruitment and data collection strategies to help optimise the design of a future phase III trial. DISCUSSION: To know whether SABR is a better, equivalent or inferior alternative to surgery for higher risk patients is a key question in lung cancer. Other studies comparing SABR to surgery have closed early due to poor recruitment, and therefore, the SABRTooth feasibility study has been designed around the UK National Health Service (NHS) cancer pathway incorporating many design features in order to maximise recruitment for a future definitive phase III trial. TRIAL REGISTRATION: controlled-trials.com ISRCTN13029788.

4.
Eur J Cancer ; 54: 57-63, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26722766

RESUMO

PURPOSE: The addition of bisphosphonates to adjuvant therapy improves survival in postmenopausal breast cancer (BC) patients. We report a meta-analysis of four randomised trials of neoadjuvant chemotherapy (CT) +/- zoledronic acid (ZA) in stage II/III BC to investigate the potential for enhancing the pathological response. METHODS: Individual patient data from four prospective randomised clinical trials reporting the effect of the addition of ZA on the pathological response after neoadjuvant CT were pooled. Primary outcomes were pathological complete response in the breast (pCRb) and in the breast and lymph nodes (pCR). Trial-level and individual patient data meta-analyses were done. Predefined subgroup-analyses were performed for postmenopausal women and patients with triple-negative BC. RESULTS: pCRb and pCR data were available in 735 and 552 patients respectively. In the total study population ZA addition to neoadjuvant CT did not increase pCRb or pCR rates. However, in postmenopausal patients, the addition of ZA resulted in a significant, near doubling of the pCRb rate (10.8% for CT only versus 17.7% with CT+ZA; odds ratio [OR] 2.14, 95% confidence interval [CI] 1.01-4.55) and a non-significant benefit of the pCR rate (7.8% for CT only versus 14.6% with CT+ZA; OR 2.62, 95% CI 0.90-7.62). In patients with triple-negative BC a trend was observed favouring CT+ZA. CONCLUSION: This meta-analysis shows no impact from the addition of ZA to neoadjuvant CT on pCR. However, as has been seen in the adjuvant setting, the addition of ZA to neoadjuvant CT may augment the effects of CT in postmenopausal patients with BC.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Neoplasias da Mama/terapia , Difosfonatos/uso terapêutico , Imidazóis/uso terapêutico , Terapia Neoadjuvante/métodos , Conservadores da Densidade Óssea/efeitos adversos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Quimioterapia Adjuvante , Difosfonatos/efeitos adversos , Feminino , Humanos , Imidazóis/efeitos adversos , Metástase Linfática , Estadiamento de Neoplasias , Pós-Menopausa , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Ácido Zoledrônico
5.
Proc Biol Sci ; 267(1457): 2093-8, 2000 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-11416914

RESUMO

Life-history theory proposes that costs must be associated with reproduction. Many direct costs are incurred during breeding. There is also evidence for indirect costs, incurred after breeding, which decrease survival and future reproductive success. One possible indirect cost identified in birds is that breeding activity in some way compromises plumage quality in the subsequent moult. Here we propose a mechanism by which this could occur. Breeding activity delays the start of moult. Birds that start to moult later also moult more rapidly--an effect of decreasing daylength. Could this result in poorer quality plumage? We kept two groups of male European starlings, Sturnus vulgaris, one on constant long days and the other on decreasing daylengths from the start of moult. Decreasing daylengths reduced the duration of moult from 103 +/- 4 days to 73 +/- 3 days (p < 0.0001). Newly grown primary feathers of birds that moulted fast were slightly shorter, weighed less (p < 0.05) and were more asymmetrical. They had a thinner rachis (p < 0.005), were less hard (p < 0.01) and less rigid (p < 0.05). They were also less resistant to wear so that differences in mass and asymmetry increased with time. There was no difference in Young's modulus. Poorer quality plumage will lead to decreased survival due to decreased flight performance and increased thermoregulatory costs. Thus, reproduction incurs costs through a mechanism that operates after the end of breeding.


Assuntos
Plumas/crescimento & desenvolvimento , Muda/fisiologia , Aves Canoras/crescimento & desenvolvimento , Aves Canoras/fisiologia , Animais , Regulação da Temperatura Corporal/fisiologia , Voo Animal/fisiologia , Masculino , Modelos Biológicos , Fotoperíodo , Reprodução/fisiologia
6.
Oecologia ; 115(1-2): 127-136, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28308443

RESUMO

The nuthatch, Sitta europaea L., is a small (23 g), cavity-nesting woodland bird which, since the 1970s, has been expanding its range in Britain. However, within this range, the species is notably scarce in an area of eastern England. This gap in the species distribution could arise for several reasons including habitat quality, local landscape structure, regional landscape structure and climate. Field surveys and logistic models of breeding nuthatch presence/absence were used to investigate the relative influences of habitat quality, landscape structure and climate on the prevalence of nuthatches in eastern England. Field surveys of woods in the study area indicated that habitat quality was sufficient to support a nuthatch population. A model of habitat occupancy in relation to local landscape structure, developed in the Netherlands, was applied to the study area. The number of breeding pairs predicted for the study area by the model was lower than expected from habitat area alone, suggesting an additional effect of isolation. However, observed numbers were even lower than those predicted by the model. To evaluate the possible roles of climate and large-scale landscape structure on distribution, presence/absence data of breeding nuthatches at the 10-km grid square scale were related to variables describing climate and the amount and dispersion of broadleaved woodland. While climate in the study area appeared suitable, models including landscape variables suggested that the study area as a whole was unlikely to support nuthatches. Although suitable habitat was available, woodland in the study area appeared to be too isolated from surrounding nuthatch populations for colonisation to be successful. This situation may change if current increases in both national and regional populations continue, thus increasing the number of potential colonists reaching the study area.

7.
Oecologia ; 105(1): 100-106, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28307128

RESUMO

Distributions of individual bird species in 151 small woods (size range 0.02-30 ha) were investigated in 3 consecutive years during which the abundance of certain species varied markedly. Relationships between the probabilities of certain bird species breeding and woodland area were described using incidence functions derived from logistic regression analysis. In general, for species which were largely dependent on woodland and seldom occurred in other habitats (such as hedgerows and gardens), the probability of breeding approached 100% only for woods of 10 ha and more, whereas species with less stringent habitat requirements occurred in the majority of woods, including those of 1 ha and less. The sensitivity of incidence functions to changes in regional abundance and the size distribution of the study woods was examined. For some species, distribution patterns could not be distinguished from those expected if pairs had been distributed in proportion to woodland area (random placement), but the majority did not conform to random placement in at least 1 of the 3 years. This nonconformity was consistent across all 3 years for some species, such as wren (Troglodytes troglodytes), despite substantial fluctuations in population sizes between years, while for others, such as robin (Erithacus rubecula), distribution patterns changed with changes in regional abundance. The results suggested that some species, such as wren and blackbird (Turdus merula), preferred small woods, while other species, such as chiffchaff (Phylloscopus collybita), preferred large woods. For several other species, including robin, great tit (Parus major), long-tailed tit (Aegithalos caudatus) and marsh tit (P. palustris), small woods appeared to be sub-optimal under at least some conditions.

8.
Biochemistry ; 33(6): 1455-66, 1994 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-8312265

RESUMO

We report the fluorescence decay kinetics and the vibrational properties of chlorophyll a bound to the 47-kDa antenna protein (CP47) of spinach photosystem II. The chlorophyll fluorescence of CP47 samples decays with four lifetimes (tau = 75.8 ps, 1.05 ns, 3.22 ns, and 5.41 ns). The 75.8-ps and 3.22-ns components are associated with chlorophyll a bound to relatively intact centers, the 1.05-ns component corresponds to chlorophyll bound to centers that are slightly perturbed, and the the 5.41-ns phase probably originates from centers that are severely denatured. The resonance Raman spectrum of CP47 at 441.6 nm (this work) and at 406.7 nm [de Paula, J. C., Ghanotakis, D. F., Bowlby, N. R., Dekker, J. P., Yocum, C. F., & Babcock, G. T. (1990) in Current Research in Photosynthesis (Baltscheffsky, M., Ed.), Vol. I, pp 643-646, Kluwer Academic Publishers, Dordrecht, The Netherlands] shows heterogeneity in the C = O stretching region. This part of the spectrum monitors the environment of the keto group at position 9 of the chlorophyll a molecule. We show that several structurally distinct pools of chlorophyll a are bound to CP47. Four of these may be distinguished by their C9 = O stretching frequencies (nu C = O = 1670, 1688, 1693, and 1701 cm-1). By analyzing the resonance enhancement pattern of these modes, we ascribe the 1693-cm-1 vibration to denatured centers. Of the remaining populations, we propose that the 1670-cm-1 vibration is consistent with a hydrogen bond between the C9 = O group of chlorophyll a and the protein. We elaborate on the role of this chromophore-protein interaction in the mechanism of energy transfer within the 47-kDa antenna protein.


Assuntos
Complexos de Proteínas Captadores de Luz , Complexo de Proteínas do Centro de Reação Fotossintética/química , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Complexo de Proteína do Fotossistema II , Plantas/química , Espectrometria de Fluorescência , Análise Espectral Raman , Clorofila/metabolismo , Clorofila A , Glucosídeos , Ligação de Hidrogênio , Cinética , Solubilidade , Relação Estrutura-Atividade
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