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1.
Radiother Oncol ; 198: 110381, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38879130

ABSTRACT

BACKGROUND AND PURPOSE: High dose-rate (HDR) brachytherapy as a monotherapy is an accepted treatment for localized prostate cancer, but the optimal dose and fractionation schedule remain unknown. We report on the efficacy of a randomized Phase II trial comparing HDR monotherapy delivered as 27 Gy in 2 fractions vs. 19 Gy in 1 fraction with a median follow-up of 9 years. MATERIALS AND METHODS: Enrolled patients had low or intermediate-risk disease, <60 cc prostate volume and no androgen deprivation use. Patients were randomized to 27 Gy in 2 fractions delivered one week apart vs a single fraction of 19 Gy. RESULTS: 170 patients were randomized: median age 65 years, median follow-up 107 months and median baseline PSA 6.35 ng/ml. NCCN risk categories comprised low (19 %), favourable (51 %), and unfavourable intermediate risk (30 %). The median PSA at 8 years was 0.08 ng/ml in the 2-fraction arm vs. 0.89 ng/ml in the single-fraction arm. The cumulative incidence of local failure at 8 years was 11.2 % in the 2-fraction arm vs. 35.9 % in the single-fraction arm (p < 0.001). The incidence of distant failure at 8 years was 3.8 % in the 2-fraction arm and 2.5 % in the single-fraction arm (p = 0.6). CONCLUSIONS: HDR monotherapy delivered in two fractions of 13.5 Gy demonstrated a persistent cancer control rate at 8 years and was well-tolerated. Single-fraction monotherapy yielded poor oncologic control and is not recommended. These findings contribute to the ongoing discourse on optimal HDR monotherapy strategies for low and intermediate-risk prostate cancer.

2.
J Phys Chem Lett ; 15(15): 4130-4135, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38593182

ABSTRACT

Molecular spins provide potential building units for future quantum information science and spintronic technologies. In particular, doublet (S = 1/2) and triplet (S = 1) molecular spin states have the potential for excellent optical and spin properties for these applications if useful photon-spin mechanisms at room temperature can be devised. Here we explore the potential of exploiting reversible energy transfer between triplet and doublet states to establish magnetosensitive luminescence and spin polarization. We investigate the dependence of the photon-spin mechanism on the magnitude and sign of the exchange interaction between the doublet and triplet spin components in amorphous and crystalline model systems. The design of a magnetic field inclination sensor is proposed from understanding the required "structure" (spin interactions) to "function" (magnetosensitivity).

3.
Pilot Feasibility Stud ; 9(1): 34, 2023 Mar 03.
Article in English | MEDLINE | ID: mdl-36869406

ABSTRACT

BACKGROUND: Cognitive problems associated with dementia affect a large proportion of older adults living in residential care. Knowledge of cognitive impairments is important for providing person-centred care (PCC). The impact of specific cognitive impairments on residents' needs is often overlooked in dementia training and information about residents' individual cognitive profiles are frequently underspecified in care-plans, potentially undermining the delivery of PCC. This can lead to reduced resident quality of life and increased distressed behaviours-a major cause of staff stress and burnout. The COG-D package was developed to fill this gap. Daisies provide a visual representation of a resident's individual cognitive strengths and weaknesses in a colourful flower (Daisy) representing five cognitive domains. By viewing a resident's Daisy, care-staff can flexibly adjust in-the-moment care-decisions and can consult Daisies in care-plans for longer-term planning. The primary aim of this study is to assess the feasibility of implementing the COG-D package in residential care homes for older adults. METHODS/DESIGN: This 24-month feasibility cluster randomized controlled trial involves a 6-month intervention of the use of Cognitive Daisies in 8-10 residential care homes for older adults after training of care staff on the use of Cognitive Daisies in daily care (basic training) and on conducting the COG-D assessments with residents (advanced training). The key feasibility outcomes include % residents recruited, % COG-D assessments completed, and % staff completing the training. Candidate outcome measures for residents and staff will be obtained at baseline, and at 6 and 9 months post-randomization. COG-D assessments of residents will be repeated 6 months after the first assessment. A process evaluation will assess intervention implementation and barriers and facilitators to this through care-plan audits, interviews and focus groups with staff, residents, and relatives. Feasibility outcomes will be analysed against progression criteria to a full trial. DISCUSSION: The results of this study will provide important information about the feasibility of using COG-D in care homes and will inform the design of a future large-scale cluster RCT to assess the effectiveness and cost-effectiveness of the COG-D intervention in care homes. TRIAL REGISTRATION: This trial was registered on 28/09/2022 (ISRCTN15208844) and is currently open to recruitment.

4.
Laterality ; 28(1): 1-31, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36205529

ABSTRACT

ABSTRACTStudies have highlighted an association between motor laterality and speech production laterality. It is thought that common demands for sequential processing may underlie this association. However, most studies in this area have relied on relatively small samples and have infrequently explored the reliability of the tools used to assess lateralization. We, therefore, established the validity and reliability of an online battery measuring sequence-based motor laterality and language laterality before exploring the associations between laterality indices on language and motor tasks. The online battery was completed by 621 participants, 52 of whom returned to complete the battery a second time. The three motor tasks included in the battery showed good between-session reliability (r ≥ .78) and were lateralized in concordance with hand preference. The novel measure of speech production laterality was left lateralized at population level as predicted, but reliability was less satisfactory (r = .62). We found no evidence of an association between sequence-based motor laterality and language laterality. Those with a left-hand preference were more strongly lateralized on motor tasks requiring midline crossing; this effect was not observed in right-handers. We conclude that there is little evidence of the co-lateralization of language and sequence-based motor skill on this battery.


Subject(s)
Functional Laterality , Language , Humans , Reproducibility of Results , Motor Skills , Speech
5.
Neuropsychology ; 35(2): 157-171, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33136419

ABSTRACT

Objective: Skilled motor praxis and speech production display marked asymmetries at the individual and the population level, favoring the right hand and the left hemisphere, respectively. Theories suggesting a common processing mechanism between praxis and speech are supported by evidence that shared neural architecture underlies both functions. Despite advances in understanding the neurobiology of this left-hemisphere specialization the cortical networks linking these 2 functions are rarely investigated on a behavioral level. Method: This study deploys functional transcranial doppler (fTCD) ultrasound to directly measure hemispheric activation during skilled manual praxis tasks shown to be correlated to hemispheric speech lateralization indices. In a new paradigm we test the hypothesis that praxis tasks are highly dependent on the left hemisphere's capacity for processing sequential information will be better correlated with direction and strength of hemispheric speech lateralization. Results: Across 2 experiments we first show that only certain praxis tasks (pegboard and coin-rotation) correlated with direct measurements of speech lateralization despite shared properties across all tasks tested. Second, through novel imaging of hemispheric activation during praxis, results showed that the pegboard differed in the lateralization pattern created and furthermore that it was significantly related to speech laterality indices, which was not the case for either of the other two tasks. Conclusion: These results are discussed in terms of a lateralized speech-praxis control mechanism and demonstrates that measurements of motor paradigms through the use of fTCD are reliable enough to provide a new insight to the behavioral relationship been speech and handedness. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Subject(s)
Functional Laterality/physiology , Motor Skills/physiology , Speech/physiology , Adolescent , Adult , Female , Humans , Male , Ultrasonography, Doppler, Transcranial , Young Adult
6.
Neuropsychology ; 33(8): 1101-1110, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31448940

ABSTRACT

OBJECTIVE: The concept of overlapping neural networks supporting both speech production and fine motor praxis is well accepted; however, few studies have explored the lateralized behavioral characteristics of both functions when performed simultaneously. METHOD: This study probes the characteristics of the dominant hemisphere by overloading cognitive processing via a novel dual-task paradigm. In 2 experiments, participants performed sets of motor and speech tasks under single-task and dual-task conditions. The sets of tasks differed as to the extent to which they relied on sequential processing, and we hypothesized that tasks more reliant on this type of processing would suffer a greater performance decrement under dual-task conditions. A reliable measure of hemispheric language dominance was obtained via functional transcranial Doppler (fTCD) ultrasound. RESULTS: Speech production scores in the experimental set (i.e., sequential processing) were consistently impaired under dual-task conditions, a distinction that was not seen in the control set. Results of Experiment 2 confirm those of Experiment 1, whereby speech scores were most strongly impaired under dual-task conditions, especially in the experimental set. Motor performance suffered less than speech performance in dual-task conditions in both the experimental and control sets across both experiments. CONCLUSION: Data suggest that the common processing capacity for speech and fine motor praxis can be disrupted through a dual-task paradigm. This novel behavioral data supports theories of a motor-based gestural origin for language and indicates that speech production is more sensitive to the effects of increased processing requirements than are motor skills. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Subject(s)
Brain/physiology , Executive Function/physiology , Functional Laterality/physiology , Motor Skills/physiology , Nerve Net/physiology , Speech/physiology , Adult , Brain/diagnostic imaging , Female , Functional Neuroimaging , Humans , Male , Nerve Net/diagnostic imaging , Ultrasonography, Doppler, Transcranial , Young Adult
7.
Dementia (London) ; 18(5): 1948-1958, 2019 Jul.
Article in English | MEDLINE | ID: mdl-27758959

ABSTRACT

The Cognitive Daisy is an innovative assessment system created to provide healthcare staff with an instant snapshot of the cognitive status of older adults in residential care. The Cognitive Daisy comprises a flower head consisting of 15 colour coded petals depicting information about: visual-spatial perception, comprehension, communication, memory and attention. This study confirmed the practicality of the Cognitive Daisy protocol for assessing cognition in a sample of 33 older adults living in residential care and endorsed the use of the Cognitive Daisy as a tool for recognising the cognitive status of care home residents.


Subject(s)
Cognitive Dysfunction , Dementia/psychology , Neuropsychological Tests/statistics & numerical data , Residential Facilities , Aged , Aged, 80 and over , Diffusion of Innovation , Female , Health Personnel , Humans , Independent Living , Male , Patient-Centered Care
8.
J Ultrasound Med ; 38(7): 1739-1745, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30536401

ABSTRACT

OBJECTIVES: The purpose of this study was to compare the reliability and agreement of 2 methods of 2-dimensional (2D) shear wave elastography (SWE) on liver stiffness in healthy volunteers. We also assessed effects of the prandial state and operator experience on measurements. METHODS: Two operators, 1 experienced and 1 novice, independently examined 20 healthy volunteers with 2D SWE on 2 ultrasound machines (Aixplorer [SuperSonic Imagine, Aix-en-Provence, France] and Aplio 500 [Canon Medical Systems Corporation, Otawara, Japan]). Volunteers were scanned 8 times by the operators using both machines in fasting and postprandial states. Agreement was evaluated by a Bland-Altman analysis, and the correlation was assessed by the Pearson correlation and intraclass correlation coefficients (ICCs). An analysis of variance was conducted to determine the contribution of the machine, prandial state, and operator experience to the variability. RESULTS: Agreement assessed by Bland-Altman plots showed no statistically significant difference in measured liver stiffness between the machines (mean difference, -0.8%; 95% confidence interval, -3.7%, 2.1%), with a critical difference of 1.36 kPa. The correlation was good to excellent for both the crude overall Pearson coefficient and the ICC, both measuring 0.88 (95% confidence interval, 0.82, 0.92). Subclass ICCs for the fasting state, postprandial state, novice operator, and experienced operator were 0.89, 0.88, 0.90, and 0.86, respectively. The 2-way mixed effect analysis of variance showed that the volunteers accounted for 86.3% of variation in median liver stiffness, with no statistically significant contribution from operator experience, the prandial state, or the machine (P = .108, .067, and .296, respectively). CONCLUSIONS: Our study showed that the 2D SWE techniques had a high degree of reliability and agreement in measurement of liver stiffness in a healthy population. Operator experience and the prandial state did not impart significant variability to stiffness measurements.


Subject(s)
Elasticity Imaging Techniques/methods , Fasting , Liver/diagnostic imaging , Postprandial Period , Adult , Female , Healthy Volunteers , Humans , Male , Reproducibility of Results
9.
Prog Brain Res ; 238: 145-178, 2018.
Article in English | MEDLINE | ID: mdl-30097191

ABSTRACT

A relationship between motor control and speech lateralization has long been postulated by researchers and clinicians with an interest in the functional organization of the human brain. Exactly how motor control might be related to speech representation, however, is rarely examined. This chapter examines current issues relating to the organization, development, and measurement of motor control and speech representation. We further consider from neuropsychological, developmental, neurological, and genetic perspectives that speech and fine motor control involve planning and sequencing processes, which are mediated by an integrated neural network localized to the left hemisphere. Specifically, we discuss studies from our laboratory using functional transcranial Doppler ultrasonography to determine speech laterality, correlating this with hand preference and pegboard measures of motor laterality. Our findings show that handedness, as measured by a motor skill task, can be predictive of speech laterality, both in typically developing adults and children. We have also shown that individuals with developmental motor coordination impairments also show atypical speech lateralization, providing further evidence that neurological motor and speech systems are intrinsically connected. We consider these results in the context of a left-lateralized speech-praxis center model, which could account for the relationship shown between sequence-based motor and speech tasks.


Subject(s)
Brain/physiology , Functional Laterality/physiology , Psychomotor Performance/physiology , Speech/physiology , Adult , Child , Female , Humans , Male
10.
Eur Radiol ; 28(6): 2281-2290, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29383520

ABSTRACT

OBJECTIVES: To identify dynamic contrast-enhanced (DCE) imaging parameters from MRI, CT and US that are prognostic and predictive in patients with metastatic renal cell cancer (mRCC) receiving sunitinib. METHODS: Thirty-four patients were monitored by DCE imaging on day 0 and 14 of the first course of sunitinib treatment. Additional scans were performed with DCE-US only (day 7 or 28 and 2 weeks after the treatment break). Perfusion parameters that demonstrated a significant correlation (Spearman p < 0.05) with progression-free survival (PFS) and overall survival (OS) were investigated using Cox proportional hazard models/ratios (HR) and Kaplan-Meier survival analysis. RESULTS: A higher baseline and day 14 value for Ktrans (DCE-MRI) and a lower pre-treatment vascular heterogeneity (DCE-US) were significantly associated with a longer PFS (HR, 0.62, 0.37 and 5.5, respectively). A larger per cent decrease in blood volume on day 14 (DCE-US) predicted a longer OS (HR, 1.45). We did not find significant correlations between any of the DCE-CT parameters and PFS/OS, unless a cut-off analysis was used. CONCLUSIONS: DCE-MRI, -CT and ultrasound produce complementary parameters that reflect the prognosis of patients receiving sunitinib for mRCC. Blood volume measured by DCE-US was the only parameter whose change during early anti-angiogenic therapy predicted for OS and PFS. KEY POINTS: • DCE-CT, -MRI and ultrasound are complementary modalities for monitoring anti-angiogenic therapy. • The change in blood volume measured by DCE-US was predictive of OS/PFS. • Baseline vascular heterogeneity by DCE-US has the strongest prognostic value for PFS.


Subject(s)
Antineoplastic Agents/therapeutic use , Carcinoma, Renal Cell/diagnostic imaging , Carcinoma, Renal Cell/secondary , Indoles/therapeutic use , Kidney Neoplasms/diagnostic imaging , Pyrroles/therapeutic use , Adult , Aged , Aged, 80 and over , Blood Volume , Carcinoma, Renal Cell/drug therapy , Contrast Media , Disease-Free Survival , Drug Monitoring/methods , Female , Humans , Kaplan-Meier Estimate , Kidney Neoplasms/drug therapy , Magnetic Resonance Imaging/methods , Male , Middle Aged , Multimodal Imaging/methods , Predictive Value of Tests , Prognosis , Sunitinib , Tomography, X-Ray Computed/methods , Ultrasonography/methods
11.
Biol Psychol ; 125: 173-176, 2017 04.
Article in English | MEDLINE | ID: mdl-28322988

ABSTRACT

It is well established that some individuals present with atypical, non-left hemisphere, cerebral lateralisation for language processing. However previous studies exploring the reliability of functional blood flow responses to detect lateralised activation during speech have focused only on individuals with typical left sided dominance. Here we report test-retest and between-task reliability measures obtained with functional transcranial Doppler ultrasound in 47 participants, including 9 with atypical language presentation. Results showed good test-retest reliability in atypically lateralised individuals, even after an interval of 120 days. Between-task reliability was weaker, but still within acceptable ranges.


Subject(s)
Functional Laterality/physiology , Language Development , Ultrasonography, Doppler, Transcranial/methods , Adolescent , Adult , Female , Hemodynamics/physiology , Humans , Male , Middle Aged , Reproducibility of Results , Speech/physiology , Young Adult
12.
J Neuropsychol ; 11(1): 1-13, 2017 03.
Article in English | MEDLINE | ID: mdl-26917045

ABSTRACT

Research using clinical populations to explore the relationship between hemispheric speech lateralization and handedness has focused on individuals with speech and language disorders, such as dyslexia or specific language impairment (SLI). Such work reveals atypical patterns of cerebral lateralization and handedness in these groups compared to controls. There are few studies that examine this relationship in people with motor coordination impairments but without speech or reading deficits, which is a surprising omission given the prevalence of theories suggesting a common neural network underlying both functions. We use an emerging imaging technique in cognitive neuroscience; functional transcranial Doppler (fTCD) ultrasound, to assess whether individuals with developmental coordination disorder (DCD) display reduced left-hemisphere lateralization for speech production compared to control participants. Twelve adult control participants and 12 adults with DCD, but no other developmental/cognitive impairments, performed a word-generation task whilst undergoing fTCD imaging to establish a hemispheric lateralization index for speech production. All participants also completed an electronic peg-moving task to determine hand skill. As predicted, the DCD group showed a significantly reduced left lateralization pattern for the speech production task compared to controls. Performance on the motor skill task showed a clear preference for the dominant hand across both groups; however, the DCD group mean movement times were significantly higher for the non-dominant hand. This is the first study of its kind to assess hand skill and speech lateralization in DCD. The results reveal a reduced leftwards asymmetry for speech and a slower motor performance. This fits alongside previous work showing atypical cerebral lateralization in DCD for other cognitive processes (e.g., executive function and short-term memory) and thus speaks to debates on theories of the links between motor control and language production.


Subject(s)
Functional Laterality/physiology , Language , Motor Skills Disorders/diagnostic imaging , Motor Skills Disorders/physiopathology , Ultrasonography, Doppler, Transcranial/methods , Adolescent , Adult , Cerebrovascular Circulation/physiology , Female , Humans , Language Tests , Male , Middle Aged , Motor Skills/physiology , Neuropsychological Tests , Phonetics , Young Adult
13.
Ultrasound Med Biol ; 43(3): 579-585, 2017 03.
Article in English | MEDLINE | ID: mdl-27979667

ABSTRACT

The goal of this study was to evaluate the accuracy of a non-invasive C-plane Doppler estimation of pulsatile blood flow in the lower abdominal vessels of a porcine model. Doppler ultrasound measurements from a matrix array transducer system were compared with invasive volume flow measurements made on the same vessels with a surgically implanted ultrasonic transit-time flow probe. For volume flow rates ranging from 60 to 750 mL/min, agreement was very good, with a Pearson correlation coefficient of 0.97 (p < 0.0001) and a mean bias of -4.2%. The combination of 2-D matrix array technology and fast processing gives this Doppler method clinical potential, as many of the user- and system-dependent parameters of previous methods, including explicit vessel angle and diameter measurements, are eliminated.


Subject(s)
Abdomen/blood supply , Pulsatile Flow/physiology , Regional Blood Flow/physiology , Transducers , Ultrasonography, Doppler/methods , Abdomen/diagnostic imaging , Animals , Female , Models, Animal , Reproducibility of Results , Swine
14.
Dev Cogn Neurosci ; 22: 9-17, 2016 12.
Article in English | MEDLINE | ID: mdl-27744099

ABSTRACT

Commonly displayed functional asymmetries such as hand dominance and hemispheric speech lateralisation are well researched in adults. However there is debate about when such functions become lateralised in the typically developing brain. This study examined whether patterns of speech laterality and hand dominance were related and whether they varied with age in typically developing children. 148 children aged 3-10 years performed an electronic pegboard task to determine hand dominance; a subset of 38 of these children also underwent functional Transcranial Doppler (fTCD) imaging to derive a lateralisation index (LI) for hemispheric activation during speech production using an animation description paradigm. There was no main effect of age in the speech laterality scores, however, younger children showed a greater difference in performance between their hands on the motor task. Furthermore, this between-hand performance difference significantly interacted with direction of speech laterality, with a smaller between-hand difference relating to increased left hemisphere activation. This data shows that both handedness and speech lateralisation appear relatively determined by age 3, but that atypical cerebral lateralisation is linked to greater performance differences in hand skill, irrespective of age. Results are discussed in terms of the common neural systems underpinning handedness and speech lateralisation.


Subject(s)
Brain/growth & development , Child Development/physiology , Functional Laterality/physiology , Motor Skills/physiology , Psychomotor Performance/physiology , Speech/physiology , Brain/physiology , Brain Mapping/methods , Child , Female , Humans , Male
15.
Behav Brain Res ; 301: 258-61, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26747206

ABSTRACT

The relative length of the second and fourth digits (2D:4D ratio) is sexually dimorphic and a retrospective biomarker of prenatal hormonal exposure. Low ratios indicate higher prenatal testosterone (pT) and lower estrogen exposure, whereas the reverse pattern is associated with high ratios. Elevated levels of pT exposure have long been thought to modulate hemispheric specialisation; subsequently many studies use the 2D:4D ratio as a proxy index for pT to examine the effects of prenatal hormonal exposure on lateralised cognitive abilities. Here we used Transcranial Doppler ultrasonography and digit ratio to investigate whether pT has an influence on speech laterality. We tested 34 right and 14 left handed adults. Our results indicate that speech representation is unrelated to digit characteristics and therefore purportedly pT. We discuss these findings in relation to androgen theories of lateralisation.


Subject(s)
Brain/physiology , Fingers/anatomy & histology , Functional Laterality/physiology , Speech/physiology , Female , Fingers/growth & development , Fingers/physiology , Humans , Language Tests , Male , Neuropsychological Tests , Pregnancy , Prenatal Exposure Delayed Effects , Testosterone/metabolism , Ultrasonography, Doppler, Transcranial , Young Adult
16.
Ultrasound Med Biol ; 42(3): 763-8, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26712416

ABSTRACT

This study evaluated the impact of different acquisition methods, user-directed region of interest placement and post-processing steps on the quantification of dynamic contrast-enhanced ultrasound measurements of blood volume in 29 patients with renal cancer, pre- and post-treatment. Specifically, we compared tumor quantification using multiple planes versus a single plane, breathhold versus free breathing and large region of interest versus a region targeting the area of highest vascularity. Performance was evaluated using area under the receiver operating characteristic curves to identify the method that best predicts progression-free survival. The intra-class correlation coefficient was also used to investigate how the same parameters affect inter-observer agreement. Of the different methods used to quantify blood volume in this study, the combination that had the highest level of inter-observer agreement (intra-class correlation coefficient = 0.8-0.97) and was the best predictor of progression-free survival was the change in blood volume measured (area under receiver operating characteristic curve = 0.77, p = 0.04) by a multiplane average, acquired during quiet breathing, quantified using a region of interest that encompassed the entire tumor.


Subject(s)
Carcinoma, Renal Cell/diagnostic imaging , Carcinoma, Renal Cell/prevention & control , Kidney Neoplasms/diagnostic imaging , Kidney Neoplasms/prevention & control , Neovascularization, Pathologic/diagnostic imaging , Ultrasonography/methods , Adult , Aged , Aged, 80 and over , Angiogenesis Inhibitors/therapeutic use , Carcinoma, Renal Cell/complications , Contrast Media , Disease-Free Survival , Drug Monitoring/methods , Female , Humans , Image Interpretation, Computer-Assisted/methods , Indoles/therapeutic use , Kidney Neoplasms/complications , Male , Middle Aged , Molecular Targeted Therapy/methods , Neovascularization, Pathologic/complications , Neovascularization, Pathologic/prevention & control , Observer Variation , Patient Positioning , Pyrroles/therapeutic use , Reproducibility of Results , Sensitivity and Specificity , Sunitinib , Treatment Outcome
17.
Eur J Radiol ; 84(9): 1650-7, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26231046

ABSTRACT

Quantitative imaging is a crucial component of the assessment of therapies that target the vasculature of angiogenic or inflamed tissue. Dynamic contrast-enhanced ultrasound (DCE-US) using microbubble contrast offers the advantages of being sensitive to perfusion, non-invasive, cost effective and well suited to repeated use at the bedside. Uniquely, it employs an agent that is truly intravascular. This papers reviews the principles and methodology of DCE-US, especially as applied to anti-angiogenic cancer therapies. Reproducibility is an important attribute of such a monitoring method: results are discussed. More recent technical advances in parametric and 3D DCE-US imaging are also summarised and illustrated.


Subject(s)
Contrast Media , Image Enhancement , Inflammation/diagnostic imaging , Inflammatory Bowel Diseases/diagnostic imaging , Neoplasms/diagnostic imaging , Humans , Imaging, Three-Dimensional , Inflammation/therapy , Inflammatory Bowel Diseases/therapy , Microbubbles , Neoplasms/therapy , Reproducibility of Results , Ultrasonography, Doppler, Color
18.
Urol Oncol ; 33(4): 171-8, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25934535

ABSTRACT

BACKGROUND: Increased sunitinib exposure (area under the curve) is associated with better outcome in metastatic renal cell cancer. Recommendations for dose modification do not take this into account. A treatment strategy, based on individual patient toxicity, was developed to maximize dose and minimize time without therapy for patients who could not tolerate the standard sunitinib schedule of 50mg given for 28 days with a 14-day break (50mg, 28/14). METHODS: A single-center retrospective review was conducted on patients with metastatic renal cell cancer treated from October 2005 to March 2010. Dose/schedule modifications (DSM) were done to keep toxicity (hematological, fatigue, skin, and gastrointestinal) at ≤ grade 2. DSM-1 was 50mg, 14 days on/7 days off with individualized increases in days on treatment. DSM-2 was 50mg, 7 days on/7 days off with individualized increase in days on treatment. DSM-3 was 37.5mg with individualized 7-day breaks. DSM-4 was 25mg with individualized 7-day breaks. Multivariable analysis was performed for outcome as a function of patient and treatment variables. RESULTS: Overall, 172 patients were included in the analysis. Most patients had clear cell histology (79.1%) with sunitinib given as a first-line therapy in 59%. The DSM-1 and 2 and DSM-3 and 4 groups had a progression-free survival (PFS) (10.9-11.9 mo) and overall survival (OS) (23.4-24.5 mo) that was significantly better than the PFS (5.3 mo; P<0.001) and OS (14.4 mo; P = 0.03 and 0.003) for the standard schedule (50mg, 28/14). DCE-US in a subset of patients showed that maximum antiangiogenic activity was achieved after 14 days on therapy. CONCLUSIONS: Individualized sunitinib scheduling based on toxicity may improve PFS and OS. This hypothesis is supported by several other respective data that are reviewed. A confirmatory prospective trial is ongoing.

19.
Phys Med Biol ; 60(6): 2195-215, 2015 Mar 21.
Article in English | MEDLINE | ID: mdl-25683789

ABSTRACT

Flat, λ/2-spaced phased arrays for therapeutic ultrasound were examined in silico and in vitro. All arrays were made by combining modules made of 64 square elements with 1.5 mm inter-element spacing along both major axes. The arrays were designed to accommodate integrated, co-aligned diagnostic transducers for targeting and monitoring. Six arrays of 1024 elements (16 modules) and four arrays of 6144 elements (96 modules) were modelled and compared according to metrics such as peak pressure amplitude, focal size, ability to be electronically-steered far off-axis and grating lobe amplitude. Two 1024 element prototypes were built and measured in vitro, producing over 100 W of acoustic power. In both cases, the simulation model of the pressure amplitude field was in good agreement with values measured by hydrophone. Using one of the arrays, it was shown that the peak pressure amplitude dropped by only 24% and 25% of the on-axis peak pressure amplitude when steered to the edge of the array (40 mm) at depths of 30 mm and 50 mm. For the 6144 element arrays studied in in silico only, similarly high steerability was found: even when steered 100 mm off-axis, the pressure amplitude decrease at the focus was less than 20%, while the maximum pressure grating lobe was only 20%. Thermal simulations indicate that the modules produce more than enough acoustic power to perform rapid ablations at physiologically relevant depths and steering angles. Arrays such as proposed and tested in this study have enormous potential: their high electronic steerability suggests that they will be able to perform ablations of large volumes without the need for any mechanical translation.


Subject(s)
High-Intensity Focused Ultrasound Ablation/instrumentation , Transducers , Algorithms , High-Intensity Focused Ultrasound Ablation/methods
20.
EMBO Mol Med ; 6(12): 1561-76, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25361689

ABSTRACT

Thousands of cancer patients are currently in clinical trials evaluating antiangiogenic therapy in the neoadjuvant setting, which is the treatment of localized primary tumors prior to surgical intervention. The rationale is that shrinking a tumor will improve surgical outcomes and minimize growth of occult micrometastatic disease-thus delaying post-surgical recurrence and improving survival. But approved VEGF pathway inhibitors have not been tested in clinically relevant neoadjuvant models that compare pre- and post-surgical treatment effects. Using mouse models of breast, kidney, and melanoma metastasis, we demonstrate that primary tumor responses to neoadjuvant VEGFR TKI treatment do not consistently correlate with improved post-surgical survival, with survival worsened in certain settings. Similar negative effects did not extend to protein-based VEGF pathway inhibitors and could be reversed with altered dose, surgical timing, and treatment duration, or when VEGFR TKIs are combined with metronomic 'anti-metastatic' chemotherapy regimens. These studies represent the first attempt to recapitulate the complex clinical parameters of neoadjuvant therapy in mice and identify a novel tool to compare systemic antiangiogenic treatment effects on localized and disseminated disease.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Indoles/administration & dosage , Neoadjuvant Therapy , Neoplasm Metastasis/drug therapy , Neoplasms/drug therapy , Pyrroles/administration & dosage , Animals , Humans , Mice , Mice, SCID , Neoplasm Metastasis/genetics , Neoplasms/genetics , Neoplasms/metabolism , Neoplasms/pathology , Sunitinib , Treatment Outcome , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism
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