ABSTRACT
Background: Nonauditory symptoms can be a prominent feature in patients with sporadic vestibular schwannoma (VS), but the cause of these symptoms is unknown. Inflammation is hypothesized to play a key role in the growth and symptomatic presentation of sporadic VS, and in this study, we investigated through translocator protein (TSPO) positron emission tomography (PET) whether inflammation occurred within the "normal appearing" brain of such patients and its association with tumor growth. Methods: Dynamic PET datasets from 15 patients with sporadic VS (8 static and 7 growing) who had been previously imaged using the TSPO tracer [11C](R)-PK11195 were included. Parametric images of [11C](R)-PK11195 binding potential (BPND) and the distribution volume ratio (DVR) were derived and compared across VS growth groups within both contralateral and ipsilateral gray (GM) and white matter (WM) regions. Voxel-wise cluster analysis was additionally performed to identify anatomical regions of increased [11C](R)-PK11195 binding. Results: Compared with static tumors, growing VS demonstrated significantly higher cortical (GM, 1.070 vs. 1.031, Pâ =â .03) and whole brain (GM & WM, 1.045 vs. 1.006, Pâ =â .03) [11C](R)-PK11195 DVR values. The voxel-wise analysis supported the region-based analysis and revealed clusters of high TSPO binding within the precentral, postcentral, and prefrontal cortex in patients with growing VS. Conclusions: We present the first in vivo evidence of increased TSPO expression and inflammation within the brains of patients with growing sporadic VS. These results provide a potential mechanistic insight into the development of nonauditory symptoms in these patients and highlight the need for further studies interrogating the role of neuroinflammation in driving VS symptomatology.
ABSTRACT
A key limitation of current dynamic contrast enhanced (DCE) MRI techniques is the requirement for full-dose gadolinium-based contrast agent (GBCA) administration. The purpose of this feasibility study was to develop and assess a new low GBCA dose protocol for deriving high-spatial resolution kinetic parameters from brain DCE-MRI. Nineteen patients with intracranial skull base tumours were prospectively imaged at 1.5 T using a single-injection, fixed-volume low GBCA dose, dual temporal resolution interleaved DCE-MRI acquisition. The accuracy of kinetic parameters (ve, Ktrans, vp) derived using this new low GBCA dose technique was evaluated through both Monte-Carlo simulations (mean percent deviation, PD, of measured from true values) and an in vivo study incorporating comparison with a conventional full-dose GBCA protocol and correlation with histopathological data. The mean PD of data from the interleaved high-temporal-high-spatial resolution approach outperformed use of high-spatial, low temporal resolution datasets alone (p < 0.0001, t-test). Kinetic parameters derived using the low-dose interleaved protocol correlated significantly with parameters derived from a full-dose acquisition (p < 0.001) and demonstrated a significant association with tissue markers of microvessel density (p < 0.05). Our results suggest accurate high-spatial resolution kinetic parameter mapping is feasible with significantly reduced GBCA dose.
Subject(s)
Brain Neoplasms , Contrast Media , Humans , Feasibility Studies , Magnetic Resonance Imaging/methods , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/pathology , Brain/diagnostic imaging , Brain/pathologyABSTRACT
ABSTRACT: We compared a combination of the nonsedating antioxidant, alpha-lipoic acid (ALA), with the sedating anticonvulsant, pregabalin, vs each monotherapy to treat neuropathic pain due to peripheral neuropathies. In this randomized, double-blind, 3-period crossover trial, participants received oral ALA, pregabalin, and their combination-each for 6 weeks. The primary outcome was mean daily pain intensity at maximal tolerated doses (MTD); secondary outcomes included quality of life (SF-36), sleep (Medical Outcomes Study-Sleep Scale), adverse effects, drug doses, and other measures. Of 55 participants randomized (20-diabetic neuropathy, 19-small fiber neuropathy, and 16-other neuropathies), 46 completed 2 periods, and 44 completed 3. At MTD, the primary outcome of mean pain intensity (0-10) was 5.32 (standard error, SE = 0.18), 3.96 (0.25), 3.25 (0.25), and 3.16 (0.25) at baseline, ALA, pregabalin, and combination, respectively ( P < 0.01 for ALA vs combination and pregabalin). Treatment differences were similar in subgroups with diabetic neuropathy and with other neuropathies. SF-36 total scores (higher number indicates better quality of life) were 66.6 (1.88), 70.1 (1.88), and 69.4 (1.87) with ALA, pregabalin, and combination ( P < 0.05 for ALA vs combination and pregabalin). At MTD, there were no statistically significant treatment differences in adverse effects or drug doses. This trial demonstrates superiority of pregabalin vs ALA but provides no evidence to suggest added benefit of combining ALA with pregabalin to treat neuropathic pain.
Subject(s)
Diabetic Neuropathies , Neuralgia , Thioctic Acid , Humans , Pregabalin/therapeutic use , Thioctic Acid/therapeutic use , Diabetic Neuropathies/drug therapy , Analgesics/therapeutic use , Quality of Life , gamma-Aminobutyric Acid/therapeutic use , Treatment Outcome , Neuralgia/drug therapy , Neuralgia/chemically induced , Double-Blind MethodABSTRACT
This study aimed to develop and evaluate a new DCE-MRI processing technique that combines LEGATOS, a dual-temporal resolution DCE-MRI technique, with multi-kinetic models. This technique enables high spatial resolution interrogation of flow and permeability effects, which is currently challenging to achieve. Twelve patients with neurofibromatosis type II-related vestibular schwannoma (20 tumours) undergoing bevacizumab therapy were imaged at 1.5 T both before and at 90 days following treatment. Using the new technique, whole-brain, high spatial resolution images of the contrast transfer coefficient (Ktrans), vascular fraction (vp), extravascular extracellular fraction (ve), capillary plasma flow (Fp), and the capillary permeability-surface area product (PS) could be obtained, and their predictive value was examined. Of the five microvascular parameters derived using the new method, baseline PS exhibited the strongest correlation with the baseline tumour volume (p = 0.03). Baseline ve showed the strongest correlation with the change in tumour volume, particularly the percentage tumour volume change at 90 days after treatment (p < 0.001), and PS demonstrated a larger reduction at 90 days after treatment (p = 0.0001) when compared to Ktrans or Fp alone. Both the capillary permeability-surface area product (PS) and the extravascular extracellular fraction (ve) significantly differentiated the 'responder' and 'non-responder' tumour groups at 90 days (p < 0.05 and p < 0.001, respectively). These results highlight that this novel DCE-MRI analysis approach can be used to evaluate tumour microvascular changes during treatment and the need for future larger clinical studies investigating its role in predicting antiangiogenic therapy response.
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Diurnal and seasonal rhythmicity, entrained by environmental and nutritional cues, is a vital part of all life on Earth operating at every level of organization; from individual cells, to multicellular organisms, whole ecosystems and societies. Redox processes are intrinsic to physiological function and circadian regulation, but how they are integrated with other regulatory processes at the whole-body level is poorly understood. Circadian misalignment triggered by a major stressor (e.g. viral infection with SARS-CoV-2) or recurring stressors of lesser magnitude such as shift work elicit a complex stress response that leads to desynchronization of metabolic processes. This in turn challenges the system's ability to achieve redox balance due to alterations in metabolic fluxes (redox rewiring). We infer that the emerging 'alternative redox states' do not always revert readily to their evolved natural states; 'Long COVID' and other complex disorders of unknown aetiology are the clinical manifestations of such rearrangements. To better support and successfully manage bodily resilience to major stress and other redox challenges needs a clear perspective on the pattern of the hysteretic response for the interaction between the redox system and the circadian clock. Characterization of this system requires repeated (ideally continuous) recording of relevant clinical measures of the stress responses and whole-body redox state (temporal redox phenotyping). The human/animal body is a complex 'system of systems' with multi-level buffering capabilities, and it requires consideration of the wider dynamic context to identify a limited number of stress-markers suitable for routine clinical decision making. Systematically mapping the patterns and dynamics of redox biomarkers along the stressor/disease trajectory will provide an operational model of whole-body redox regulation/balance that can serve as basis for the identification of effective interventions which promote health by enhancing resilience.
Subject(s)
COVID-19 , Ecosystem , Animals , Humans , Health Promotion , SARS-CoV-2 , Circadian Rhythm , Oxidation-ReductionABSTRACT
Background: Tumour apparent diffusion coefficient (ADC) from diffusion-weighted magnetic resonance imaging (MRI) is a putative pharmacodynamic/response biomarker but the relationship between drug-induced effects on the ADC and on the underlying pathology has not been adequately defined. Hypothesis: Changes in ADC during early chemotherapy reflect underlying histological markers of tumour response as measured by tumour regression grade (TRG). Methods: Twenty-six patients were enrolled in the study. Baseline, 14 days, and pre-surgery MRI were performed per study protocol. Surgical resection was performed in 23 of the enrolled patients; imaging-pathological correlation was obtained from 39 lesions from 21 patients. Results: There was no evidence of correlation between TRG and ADC changes at day 14 (study primary endpoint), and no significant correlation with other ADC metrics. In scans acquired one week prior to surgery, there was no significant correlation between ADC metrics and percentage of viable tumour, percentage necrosis, percentage fibrosis, or Ki67 index. Conclusions: Our hypothesis was not supported by the data. The lack of meaningful correlation between change in ADC and TRG is a robust finding which is not explained by variability or small sample size. Change in ADC is not a proxy for TRG in metastatic colorectal cancer.
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Based on the Global Cancer Update Programme, formally known as the World Cancer Research Fund/American Institute for Cancer Research Continuous Update Project, we performed systematic reviews and meta-analyses to investigate the association of postdiagnosis body fatness, physical activity and dietary factors with breast cancer prognosis. We searched PubMed and Embase for randomised controlled trials and longitudinal observational studies from inception to 31 October 2021. We calculated summary relative risks (RRs) and 95% confidence intervals (CIs) using random-effects meta-analyses. An independent Expert Panel graded the quality of evidence according to predefined criteria. The evidence on postdiagnosis body fatness and higher all-cause mortality (RR per 5 kg/m2 in body mass index: 1.07, 95% CI: 1.05-1.10), breast cancer-specific mortality (RR: 1.10, 95% CI: 1.06-1.14) and second primary breast cancer (RR: 1.14, 95% CI: 1.04-1.26) was graded as strong (likelihood of causality: probable). The evidence for body fatness and breast cancer recurrence and other nonbreast cancer-related mortality was graded as limited (likelihood of causality: limited-suggestive). The evidence on recreational physical activity and lower risk of all-cause (RR per 10 metabolic equivalent of task-hour/week: 0.85, 95% CI: 0.78-0.92) and breast cancer-specific mortality (RR: 0.86, 95% CI: 0.77-0.96) was judged as limited-suggestive. Data on dietary factors was limited, and no conclusions could be reached except for healthy dietary patterns, isoflavone and dietary fibre intake and serum 25(OH)D concentrations that were graded with limited-suggestive evidence for lower risk of the examined outcomes. Our results encourage the development of lifestyle recommendations for breast cancer patients to avoid obesity and be physically active.
Subject(s)
Breast Neoplasms , Humans , Female , Breast Neoplasms/epidemiology , Breast Neoplasms/etiology , Neoplasm Recurrence, Local , Body Mass Index , Breast , ExerciseABSTRACT
Previous evidence on postdiagnosis body fatness and mortality after breast cancer was graded as limited-suggestive. To evaluate the evidence on body mass index (BMI), waist circumference, waist-hip-ratio and weight change in relation to breast cancer prognosis, an updated systematic review was conducted. PubMed and Embase were searched for relevant studies published up to 31 October, 2021. Random-effects meta-analyses were conducted to estimate summary relative risks (RRs). The evidence was judged by an independent Expert Panel using pre-defined grading criteria. One randomized controlled trial and 225 observational studies were reviewed (220 publications). There was strong evidence (likelihood of causality: probable) that higher postdiagnosis BMI was associated with increased all-cause mortality (64 studies, 32 507 deaths), breast cancer-specific mortality (39 studies, 14 106 deaths) and second primary breast cancer (11 studies, 5248 events). The respective summary RRs and 95% confidence intervals per 5 kg/m2 BMI were 1.07 (1.05-1.10), 1.10 (1.06-1.14) and 1.14 (1.04-1.26), with high between-study heterogeneity (I2 = 56%, 60%, 66%), but generally consistent positive associations. Positive associations were also observed for waist circumference, waist-hip-ratio and all-cause and breast cancer-specific mortality. There was limited-suggestive evidence that postdiagnosis BMI was associated with higher risk of recurrence, nonbreast cancer deaths and cardiovascular deaths. The evidence for postdiagnosis (unexplained) weight or BMI change and all outcomes was graded as limited-no conclusion. The RCT showed potential beneficial effect of intentional weight loss on disease-free-survival, but more intervention trials and well-designed observational studies in diverse populations are needed to elucidate the impact of body composition and their changes on breast cancer outcomes.
Subject(s)
Breast Neoplasms , Humans , Female , Breast Neoplasms/epidemiology , Body Mass Index , Adipose Tissue , Waist Circumference , Waist-Hip RatioABSTRACT
It is important to clarify the associations between modifiable lifestyle factors such as physical activity and breast cancer prognosis to enable the development of evidence-based survivorship recommendations. We performed a systematic review and meta-analyses to summarise the evidence on the relationship between postbreast cancer diagnosis physical activity and mortality, recurrence and second primary cancers. We searched PubMed and Embase through 31st October 2021 and included 20 observational studies and three follow-up observational analyses of patients enrolled in clinical trials. In linear dose-response meta-analysis of the observational studies, each 10-unit increase in metabolic equivalent of task (MET)-h/week higher recreational physical activity was associated with 15% and 14% lower risk of all-cause (95% confidence interval [CI]: 8%-22%, studies = 12, deaths = 3670) and breast cancer-specific mortality (95% CI: 4%-23%, studies = 11, deaths = 1632), respectively. Recreational physical activity was not associated with breast cancer recurrence (HR = 0.97, 95% CI: 0.91-1.05, studies = 6, deaths = 1705). Nonlinear dose-response meta-analyses indicated 48% lower all-cause and 38% lower breast cancer-specific mortality with increasing recreational physical activity up to 20 MET-h/week, but little further reduction in risk at higher levels. Predefined subgroup analyses across strata of body mass index, hormone receptors, adjustment for confounders, number of deaths, menopause and physical activity intensities were consistent in direction and magnitude to the main analyses. Considering the methodological limitations of the included studies, the independent Expert Panel concluded 'limited-suggestive' likelihood of causality for an association between recreational physical activity and lower risk of all-cause and breast cancer-specific mortality.
Subject(s)
Breast Neoplasms , Female , Humans , Breast Neoplasms/diagnosis , Neoplasm Recurrence, Local/epidemiology , Risk , Prognosis , Life StyleABSTRACT
Little is known about how diet might influence breast cancer prognosis. The current systematic reviews and meta-analyses summarise the evidence on postdiagnosis dietary factors and breast cancer outcomes from randomised controlled trials and longitudinal observational studies. PubMed and Embase were searched through 31st October 2021. Random-effects linear dose-response meta-analysis was conducted when at least three studies with sufficient information were available. The quality of the evidence was evaluated by an independent Expert Panel. We identified 108 publications. No meta-analysis was conducted for dietary patterns, vegetables, wholegrains, fish, meat, and supplements due to few studies, often with insufficient data. Meta-analysis was only possible for all-cause mortality with dairy, isoflavone, carbohydrate, dietary fibre, alcohol intake and serum 25-hydroxyvitamin D (25(OH)D), and for breast cancer-specific mortality with fruit, dairy, carbohydrate, protein, dietary fat, fibre, alcohol intake and serum 25(OH)D. The results, with few exceptions, were generally null. There was limited-suggestive evidence that predefined dietary patterns may reduce the risk of all-cause and other causes of death; that isoflavone intake reduces the risk of all-cause mortality (relative risk (RR) per 2 mg/day: 0.96, 95% confidence interval (CI): 0.92-1.02), breast cancer-specific mortality (RR for high vs low: 0.83, 95% CI: 0.64-1.07), and recurrence (RR for high vs low: 0.75, 95% CI: 0.61-0.92); that dietary fibre intake decreases all-cause mortality (RR per 10 g/day: 0.87, 95% CI: 0.80-0.94); and that serum 25(OH)D is inversely associated with all-cause and breast cancer-specific mortality (RR per 10 nmol/L: 0.93, 95% CI: 0.89-0.97 and 0.94, 95% CI: 0.90-0.99, respectively). The remaining associations were graded as limited-no conclusion.
Subject(s)
Dietary Supplements , Neoplasms , Animals , Diet , Dietary Fats , VegetablesABSTRACT
BACKGROUND: Physical activity (PA) is associated with improved health-related quality of life (HRQoL) among women with breast cancer; however, uncertainty remains regarding PA types and dose (frequency, duration, intensity) and various HRQoL measures. A systematic review and meta-analysis of randomized controlled trials was conducted to clarify whether specific types and doses of physical activity was related to global and specific domains of HRQoL, as part of the Global Cancer Update Programme, formerly known as the World Cancer Research Fund-American Institute for Cancer Research Continuous Update Project. METHODS: PubMed and CENTRAL databases were searched up to August 31, 2019. Weighted mean differences (WMDs) in HRQoL scores were estimated using random effects models. An independent expert panel graded the evidence. RESULTS: A total of 79 randomized controlled trials (14â554 breast cancer patients) were included. PA interventions resulted in higher global HRQoL as measured by the Functional Assessment of Cancer Therapy-Breast (WMD = 5.94, 95% confidence intervals [CI] = 2.64 to 9.24; I2 = 59%, n = 12), Functional Assessment of Cancer Therapy-General (WMD = 4.53, 95% CI = 1.94 to 7.13; I2 = 72%, n = 18), and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 (WMD = 6.78, 95% CI = 2.61 to 10.95; I2 = 76.3%, n = 17). The likelihood of causality was considered probable that PA improves HRQoL in breast cancer survivors. Effects were weaker for physical function and mental and emotional health. Evidence regarding dose and type of PA remains insufficient for firm conclusions. CONCLUSION: PA results in improved global HRQoL in breast cancer survivors with weaker effects observed for physical function and mental and emotional health. Additional research is needed to define the impact of types and doses of activity on various domains of HRQoL.
Subject(s)
Breast Neoplasms , Quality of Life , Humans , Female , Breast Neoplasms/therapy , ExerciseABSTRACT
Glioblastoma is a high-grade aggressive neoplasm characterised by significant intra-tumoral spatial heterogeneity. Personalising therapy for this tumour requires non-invasive tools to visualise its heterogeneity to monitor treatment response on a regional level. To date, efforts to characterise glioblastoma's imaging features and heterogeneity have focussed on individual imaging biomarkers, or high-throughput radiomic approaches that consider a vast number of imaging variables across the tumour as a whole. Habitat imaging is a novel approach to cancer imaging that identifies tumour regions or 'habitats' based on shared imaging characteristics, usually defined using multiple imaging biomarkers. Habitat imaging reflects the evolution of imaging biomarkers and offers spatially preserved assessment of tumour physiological processes such perfusion and cellularity. This allows for regional assessment of treatment response to facilitate personalised therapy. In this review, we explore different methodologies to derive imaging habitats in glioblastoma, strategies to overcome its technical challenges, contrast experiences to other cancers, and describe potential clinical applications.
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The interstellar objects 1I/'Oumuamua and 2I/Borisov confirm the long-held expectation that bodies from one stellar system will be carried to another, allowing, in principle, interstellar panspermia. Life might be transferred between stellar systems, depending on the nature of the bodies and how they escaped their systems. 2I/Borisov appears to be a comet, with no more likelihood of carrying life than Solar System comets. In contrast, the nature of 1I/'Oumuamua has been difficult to determine. We review various hypotheses for its origin, including ejection of N2 ice from the surface of an exo-Pluto, formation in a molecular cloud by freezing of H2, and a derelict solar sail of alien construction. Of these, the N2 ice fragment hypothesis is uniquely falsifiable, plausible, and completely consistent with all observations. The possibility of interstellar panspermia would be made more probable if 'Oumuamua originated on a dwarf planet rather than a comet, although substantial challenges to transfer of life would remain. Of proposed mechanisms for interstellar panspermia, transfer of life via rocky meteoroids is perhaps less improbable.
Subject(s)
Ice , Bees , AnimalsABSTRACT
Living organisms need to be able to cope with environmental challenges and other stressors and mount adequate responses that are as varied as the spectrum of those challenges. Understanding how the multi-layered biological stress responses become integrated across and between different levels of organization within an organism can provide a different perspective on the nature and inter-relationship of complex systems in health and disease. We here compare two concepts which have been very influential in stress research: Selye's 'General Adaptation Syndrome' and Sies's 'Oxidative Stress' paradigm. We show that both can be embraced within a more general framework of 'change and response'. The 'Reactive Species Interactome' allows each of these to be considered as distinct but complementary aspects of the same system, representative of roles at different levels of organization within a functional hierarchy. The versatile chemistry of sulfur - exemplified by hydrogen sulfide, glutathione and proteinous cysteine thiols - enriched by its interactions with reactive oxygen, nitrogen and sulfur species, would seem to sit at the heart of the 'Redox Code' and underpin the ability of complex organisms to cope with stress.