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2.
Radiography (Lond) ; 29(2): 347-354, 2023 03.
Article in English | MEDLINE | ID: mdl-36736147

ABSTRACT

INTRODUCTION: Magnetic Resonance (MR)-only radiotherapy for prostate cancer has previously been reported using fiducial markers for on-treatment verification. MR-Cone Beam Computed Tomography (CBCT) soft-tissue matching does not require invasive fiducial markers and enables MR-only treatments to other pelvic cancers. This study evaluated the first clinical implementation of MR-only prostate radiotherapy using MR-CBCT soft-tissue matching. METHODS: Twenty prostate patients were treated with MR-only radiotherapy using a synthetic (s)CT-optimised plan with MR-CBCT soft-tissue matching. Two MR sequences were acquired: small Field Of View (FOV) for target delineation and large FOV for organs at risk delineation, sCT generation and on-treatment verification. Patients also received a CT for validation. The prostate was independently contoured on the small FOV MR, copied to the registered CT and modified if there were MR-CT soft-tissue alignment differences (MR-CT volume). This was compared to the MR-only volume with a paired t-test. The treatment plan was recalculated on CT and the doses compared. Independent offline CT-CBCT matches for 5/20 fractions were performed by three therapeutic radiographers using the MR-only contours and compared to the online MR-CBCT matches using two one-sided paired t-tests for equivalence within ±1 mm. RESULTS: The MR-only volumes were significantly smaller than MR-CT (p = 0.003), with a volume ratio 0.92 ± 0.02 (mean ± standard error). The sCT isocentre dose difference to CT was 0.2 ± 0.1%. MR-CBCT soft-tissue matching was equivalent to CT-CBCT (p < 0.001), with differences of 0.1 ± 0.2 mm (vertical), -0.1 ± 0.2 mm (longitudinal) and 0.0 ± 0.1 mm (lateral). CONCLUSIONS: MR-only radiotherapy with soft-tissue matching has been successfully clinically implemented. It produced significantly smaller target volumes with high dosimetric and on-treatment matching accuracy. IMPLICATIONS FOR PRACTICE: MR-only prostate radiotherapy can be safely delivered without using invasive fiducial markers. This enables MR-only radiotherapy to be extended to other pelvic cancers where fiducial markers cannot be used.


Subject(s)
Pelvic Neoplasms , Spiral Cone-Beam Computed Tomography , Male , Humans , Prostate/diagnostic imaging , Radiotherapy Planning, Computer-Assisted/methods , Magnetic Resonance Spectroscopy
5.
Clin Obes ; 8(5): 337-344, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30066450

ABSTRACT

The increased incidence of obesity in the general population translates into clinicians caring for an increased number of trauma patients with obesity. Previous research has documented the unique anatomical and physiological challenges that clinicians face when caring for trauma patients with obesity; however, little is known about psychological challenges that trauma patients with obesity may also experience in the months following injury. The aim of this study is to determine the relationship between obesity and (i) mental health, (ii) demographic and injury-related variables and (iii) quality-of-life outcomes among trauma patients between hospitalization and 3-months post-injury. This is a prospective, longitudinal study conducted between March 2012 and May 2014 at a single, level I trauma centre in the southwest United States. Inclusion criteria for this convenience sample consisted of patients who were admitted to the trauma or orthopaedic trauma service ≥24 h, medically stable, spoke English or Spanish and ≥18 years of age. In total, 455 eligible patients were consented and enrolled; 343 (70.87%) completed 3-month follow-up. The objective of this study is to investigate the relationship between obesity and mental health among trauma patients in the months following injury. Demographic and injury-related data were also collected; patients' height and weight were used to determine body mass index. Health outcomes were assessed during initial hospitalization and at 3-month follow-up and included depression, post-traumatic stress symptoms, pain and return to work. Prior to data collection, it was hypothesized that obesity would have a negative effect on mental health outcomes among patients 3 months post-injury. The final sample consisted of 343 participants; average age was 46.4 ± 17.3 years; majority male (n = 213, 63%) and Caucasian (n = 231, 69%). Patients with obesity had higher odds of screening positive for depression (odds ratio [OR] = 2.36, P = 0.02) and overweight patients had lower odds of returning to work (OR = 0.31, P = 0.01) 3 months post-injury compared to patients of normal weight (65% vs. 40%). No other significant differences were found. Results of the current study are novel in that they identify psychological challenges that overweight and trauma patients with obesity may experience. These results demonstrate the need for mental health professionals to be involved in follow-up care to extending in the months following injury.


Subject(s)
Mental Health , Obesity/psychology , Adult , Depression , Female , Hospitalization , Humans , Longitudinal Studies , Male , Middle Aged , Obesity/therapy , Prospective Studies , Trauma Centers/statistics & numerical data , Young Adult
6.
J Appl Res Intellect Disabil ; 31 Suppl 1: 97-109, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28833967

ABSTRACT

BACKGROUND: There is a lack of health promotion programming designed to change the physical activity environment of the group home setting. The Menu-Choice programme assists staff in creating physical activity goals alongside residents with intellectual disabilities and provides strategies to incorporate activity into the group home schedule. The purpose of this study was to complete a process evaluation of Menu-Choice utilizing qualitative methods. METHODS: Twelve participants, who completed a 10-week pilot intervention (n = 7 staff, mean age 42; n = 5 residents, mean age 52), participated in face-to-face interviews. Participants represented five group home sites involved in the intervention. RESULTS: Meta-themes included: (i) Programme training, (ii) Programme implementation, (iii) Programme physical activity, (iv) Programme barriers, (v) Programme facilitators and (vi) Programme feedback. CONCLUSIONS: Changes in programme training and simplified programme materials are needed to accommodate identified barriers for implementation. The importance of obtaining increased agency support and policy change is highlighted.


Subject(s)
Exercise , Group Homes , Health Promotion/methods , Intellectual Disability/rehabilitation , Program Development , Program Evaluation , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Qualitative Research , Young Adult
7.
Spinal Cord ; 53 Suppl 1: S25-6, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25900287

ABSTRACT

STUDY DESIGN: This is a case report. OBJECTIVES: The objective of this study was to report on a brain-computer interface (BCI) paradigm that is successfully used with an inpatient spinal cord injury patient. SETTING: This study was conducted in an inpatient rehabilitation hospital. METHODS: A 25-year-old man with a C5 burst fracture and subsequent tetraplegia (The American Spinal Injury Association) participated in this case study. He completed a brief battery of psychological, pain, cognitive and other screening measures at points before and after the BCI paradigm during his rehabilitation hospitalization. RESULTS: The paradigm was easily learned and well tolerated with no adverse effects. CONCLUSIONS: This case is reflective of the trends in our ongoing feasibility study evaluating BCI technology in the inpatient rehabilitation setting. Clinical implications and challenges of using this technology in a busy hospital unit are reviewed.


Subject(s)
Brain-Computer Interfaces , Spinal Cord Injuries , Adult , Brain-Computer Interfaces/psychology , Humans , Male , Neuropsychological Tests , Spinal Cord Injuries/physiopathology , Spinal Cord Injuries/psychology , Spinal Cord Injuries/rehabilitation
8.
Lymphology ; 48(3): 139-52, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26939161

ABSTRACT

Turner syndrome (TS) is a chromosomal condition affecting an estimated 1 in 2,500 girls where the second X chromosome is missing, or partially formed. This abnormality affects multiple body systems and can lead to short stature, cardiac, neural, and renal abnormalities. Due to the chronic, non-life threatening nature of lymphedema in comparison to other symptoms of TS, it is often ignored by girls and women with TS and their physicians. Consequently, little is known about how lymphedema affects girls and women with TS across the lifespan. Therefore, the objective of the study was to deliver an online survey for females with TS and caregivers in the US, UK, and Canada to provide a worldwide perspective on their current experience with lymphedema within the spectrum of TS. There were 219 participants who completed the survey, and we were able to identify incidence and characteristics of lymphedema across the lifespan. In addition, we found that females with 45,X karyotyping were more likely to report lymphedema symptoms. Lymphedema is not the most significant concern of females with TS, but education, physician evaluation, and assistance with referrals for treatment and management would improve the ease of managing lymphedema in girls and women with TS.


Subject(s)
Lymphedema/diagnosis , Lymphedema/epidemiology , Turner Syndrome/complications , Adolescent , Adult , Age Factors , Child , Cross-Sectional Studies , Female , Humans , Lymphedema/psychology , Middle Aged , Surveys and Questionnaires , Young Adult
9.
Chem Commun (Camb) ; 51(3): 537-40, 2015 Jan 11.
Article in English | MEDLINE | ID: mdl-25412439

ABSTRACT

Physical vapour deposition of Mo on an FeS2{100} surface was performed at 170 K. Near-epitaxial growth of MoS2(0001) overlayers of the order of 1 nm thickness was observed when the Mo-covered substrate was subsequently heated to 600 K.

10.
J Phys Condens Matter ; 26(5): 056001, 2014 Feb 05.
Article in English | MEDLINE | ID: mdl-24441049

ABSTRACT

Magnetic phase transitions in RCo2 Laves phases with R as a rare earth element are accompanied by changes in crystallographic space group. For purely structural transitions they would be described as improper ferroelastic and therefore fulfil the condition for multiferroic phase transitions in combining two out of three properties, ferro/antiferromagnetism, ferroelectricity and ferroelasticity. Here lattice parameter data from the literature and new measurements of elastic and anelastic properties, by resonant ultrasound spectroscopy, for NdCo2 and ErCo2 have been analysed from this perspective. The temperature dependence of symmetry-breaking shear strains is consistent with the cubic ↔ tetragonal transition in NdCo2 being close to tricritical in character and the cubic ↔ rhombohedral transition in ErCo2 being first order. Elastic softening and acoustic loss within the stability ranges of the ferroelastic phases can be understood in terms of a combination of intrinsic softening due to strain/order parameter coupling and ferroelastic twin-wall motion. Softening ahead of the transitions does not fit with standard macroscopic descriptions of dynamic effects from other systems but, rather, in the case of NdCo2, might be attributed to the involvement of a second zone centre order parameter related to a separate instability driven by cooperative Jahn-Teller distortions. In ErCo2, acoustic loss in the temperature interval above the transition point is discussed in terms of a possible tweed microstructure associated with strain coupling to local magnetic ordering. The overall multiferroic behaviour can be understood in terms of a single magnetic order parameter (irrep mΓ+4 of magnetic space group Fd3m1') which couples with a structural order parameter (irrep Γ+3 or Γ+5). The coupling is linear/quadratic which, in the case of two separate instabilities, causes them to combine in a single multiferroic phase transition.

11.
Spinal Cord ; 52(3): 197-201, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24418959

ABSTRACT

STUDY DESIGN: Qualitative research design involving semi-structured focus groups. OBJECTIVES: To increase current understanding of how persons with spinal cord injuries (SCI) define resilience and what factors contribute to their resilience or the resilience of others. SETTING: Inpatient rehabilitation program in a large urban city in the Southwestern United States. METHODS: A convenience sample of 28 participants (14 current patients; 14 former patients) participated in semi-structured focus groups led by the research investigators. RESULTS: Through a constant comparative analysis of the data, six themes emerged in participants' responses regarding what they believed contributed to their own resilience in adapting to SCI. The six themes included psychological strength, social support, perspective, adaptive coping, spirituality or faith, and serving as a role model or inspiring others. CONCLUSION: Consistent with previous research findings, individuals with SCI identified positive thinking (for example, optimism, hope and positive attitude), perseverance and determination, and social support from friends and family as important contributors to their ability to adapt in spite of experiencing traumatic events that resulted in SCI. Findings provide richness and depth to current empirical conceptualizations of resilience.


Subject(s)
Adaptation, Psychological/physiology , Spinal Cord Injuries/rehabilitation , Adolescent , Adult , Female , Humans , Male , Middle Aged , Qualitative Research , Resilience, Psychological , Social Support , Spinal Cord Injuries/psychology , Spirituality , Young Adult
12.
Science ; 330(6005): 800-4, 2010 Nov 05.
Article in English | MEDLINE | ID: mdl-21051633

ABSTRACT

Gravitational lensing is a powerful astrophysical and cosmological probe and is particularly valuable at submillimeter wavelengths for the study of the statistical and individual properties of dusty star-forming galaxies. However, the identification of gravitational lenses is often time-intensive, involving the sifting of large volumes of imaging or spectroscopic data to find few candidates. We used early data from the Herschel Astrophysical Terahertz Large Area Survey to demonstrate that wide-area submillimeter surveys can simply and easily detect strong gravitational lensing events, with close to 100% efficiency.

13.
Brain Inj ; 19(13): 1067-75, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16286320

ABSTRACT

PRIMARY OBJECTIVE: To examine the influence of social support on the physical activity behaviours of individual's with a traumatic brain injury. MAIN OUTCOMES AND RESULTS: The paper defines social support as a multi-dimensional construct and reviews relevant literature describing how the type and source of social support changes post-brain injury. These findings are then applied to a physical activity domain with the use of a conceptual framework. Discussion finally focuses on research applications and appropriate measures of social support within a physical activity environment. CONCLUSIONS: This paper will provide physical activity programmers with an understanding of how social support influences physical activity participation, a conceptual framework to guide programming and appropriate measures of social support for research purposes.


Subject(s)
Brain Injuries/rehabilitation , Exercise , Social Support , Adolescent , Adult , Aged , Brain Injuries/psychology , Child , Exercise/psychology , Female , Health Behavior , Humans , Male , Middle Aged , Motivation
14.
Langmuir ; 21(16): 7285-91, 2005 Aug 02.
Article in English | MEDLINE | ID: mdl-16042455

ABSTRACT

Scanning tunneling microscopy (STM) has been used to investigate the structure of the ordered methanethiolate overlayer formed on Ag(111) by reaction at room temperature with dimethyl disulfide. High-resolution images show an ordered structure with three inequivalent atomic-scale protrusions within each ( radical7 x radical7)R19 degrees surface unit mesh which can be reconciled with methanethiolate species on a regular lateral submesh, similar to that proposed in the multilayer ( radical7 x radical7)R19 degrees -S sulfide phase previously reported. STM imaging during dynamic dosing also provides evidence for a significant change in the outermost layer Ag atom density, consistent with a reconstructed surface model. Possible models for this reconstruction are presented and discussed in the light of available information.

15.
Phys Rev Lett ; 95(26): 266102, 2005 Dec 31.
Article in English | MEDLINE | ID: mdl-16486373

ABSTRACT

CO adsorption on NO(2)-predosed Au[111] reveals an unexpected attractive coadsorbate interaction, associated with an unprecedented blueshift of the CO stretch frequency, a sizeable attenuation of the infrared NO(2) symmetric stretch band, and a (sq.rt(7) x sq.rt(7))R19 degrees structure characterized by scanning tunneling microscopy and low energy electron diffraction. Density functional calculations allow us to rationalize these observations, and point towards a general pattern of behavior for electronegative coadsorbates on coinage metals, with important implications for catalytic promotion.

16.
Phys Rev Lett ; 89(6): 061301, 2002 Aug 05.
Article in English | MEDLINE | ID: mdl-12190573

ABSTRACT

We constrain f(nu) identical with Omega(nu)/Omega(m), the fractional contribution of neutrinos to the total mass density in the Universe, by comparing the power spectrum of fluctuations derived from the 2 Degree Field Galaxy Redshift Survey with power spectra for models with four components: baryons, cold dark matter, massive neutrinos, and a cosmological constant. Adding constraints from independent cosmological probes we find f(nu)<0.13 (at 95% confidence) for a prior of 0.1

17.
Nature ; 410(6825): 169-73, 2001 Mar 08.
Article in English | MEDLINE | ID: mdl-11242069

ABSTRACT

The large-scale structure in the distribution of galaxies is thought to arise from the gravitational instability of small fluctuations in the initial density field of the Universe. A key test of this hypothesis is that forming superclusters of galaxies should generate a systematic infall of other galaxies. This would be evident in the pattern of recessional velocities, causing an anisotropy in the inferred spatial clustering of galaxies. Here we report a precise measurement of this clustering, using the redshifts of more than 141,000 galaxies from the two-degree-field (2dF) galaxy redshift survey. We determine the parameter beta = Omega0.6/b = 0.43 +/- 0.07, where Omega is the total mass-density parameter of the Universe and b is a measure of the 'bias' of the luminous galaxies in the survey. (Bias is the difference between the clustering of visible galaxies and of the total mass, most of which is dark.) Combined with the anisotropy of the cosmic microwave background, our results favour a low-density Universe with Omega approximately 0.3.

18.
Nat Med ; 5(12): 1390-5, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10581081

ABSTRACT

Although insulin-like growth factor 1 (IGF-1) has been associated with retinopathy, proof of a direct relationship has been lacking. Here we show that an IGF-1 receptor antagonist suppresses retinal neovascularization in vivo, and infer that interactions between IGF-1 and the IGF-1 receptor are necessary for induction of maximal neovascularization by vascular endothelial growth factor (VEGF). IGF-1 receptor regulation of VEGF action is mediated at least in part through control of VEGF activation of p44/42 mitogen-activated protein kinase, establishing a hierarchical relationship between IGF-1 and VEGF receptors. These findings establish an essential role for IGF-1 in angiogenesis and demonstrate a new target for control of retinopathy. They also explain why diabetic retinopathy initially increases with the onset of insulin treatment. IGF-1 levels, low in untreated diabetes, rise with insulin therapy, permitting VEGF-induced retinopathy.


Subject(s)
Endothelial Growth Factors/physiology , Lymphokines/physiology , Neovascularization, Pathologic/physiopathology , Receptor, IGF Type 1/physiology , Retinal Vessels/physiology , Animals , Growth Inhibitors/pharmacology , Humans , Insulin/pharmacology , Insulin-Like Growth Factor I/analogs & derivatives , Insulin-Like Growth Factor I/pharmacology , Ischemia/etiology , Ischemia/physiopathology , Ischemia/prevention & control , Mice , Mice, Inbred C57BL , Neovascularization, Pathologic/etiology , Neovascularization, Pathologic/prevention & control , Protein-Tyrosine Kinases/antagonists & inhibitors , Receptor Protein-Tyrosine Kinases/physiology , Receptor, IGF Type 1/antagonists & inhibitors , Receptors, Growth Factor/physiology , Receptors, Vascular Endothelial Growth Factor , Retinal Vessels/drug effects , Signal Transduction , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
19.
Nat Biotechnol ; 17(12): 1184-7, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10585715

ABSTRACT

We describe a technique to define gene function using antisense oligonucleotide (AS-ODN) inhibition of gene expression in mice. A single intravenous injection of an AS-ODN targeting vascular endothelial growth factor (VEGF) into pregnant mice between E7.5-8.5 resulted in a lack of primary angiogenesis. This enabled us to define the critical window required to inhibit VEGF expression and recapitulate the primary loss of function phenotype observed in VEGF (-/-) embryos. This phenotype was sequence-specific and time- and dose-dependent. Injection of an AS-ODN targeting a second gene, E-cadherin, into pregnant mice at E10 confirmed a hypothesized secondary phenotype. This is the first report of AS-ODN inhibition of gene expression in utero and provides a new strategy for target validation in functional genomics.


Subject(s)
Endothelial Growth Factors/genetics , Gene Expression Regulation, Developmental/drug effects , Lymphokines/genetics , Oligonucleotides, Antisense/pharmacology , Animals , Base Sequence , Cadherins/genetics , Dose-Response Relationship, Drug , Female , Mice , Mice, Knockout , Phenotype , Pregnancy , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
20.
Nature ; 391(6669): 806-11, 1998 Feb 19.
Article in English | MEDLINE | ID: mdl-9486653

ABSTRACT

Experimental introduction of RNA into cells can be used in certain biological systems to interfere with the function of an endogenous gene. Such effects have been proposed to result from a simple antisense mechanism that depends on hybridization between the injected RNA and endogenous messenger RNA transcripts. RNA interference has been used in the nematode Caenorhabditis elegans to manipulate gene expression. Here we investigate the requirements for structure and delivery of the interfering RNA. To our surprise, we found that double-stranded RNA was substantially more effective at producing interference than was either strand individually. After injection into adult animals, purified single strands had at most a modest effect, whereas double-stranded mixtures caused potent and specific interference. The effects of this interference were evident in both the injected animals and their progeny. Only a few molecules of injected double-stranded RNA were required per affected cell, arguing against stochiometric interference with endogenous mRNA and suggesting that there could be a catalytic or amplification component in the interference process.


Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis elegans/genetics , Gene Expression Regulation/drug effects , RNA, Double-Stranded/pharmacology , Animals , Caenorhabditis elegans/drug effects , Calmodulin-Binding Proteins/genetics , Genes, Helminth , Helminth Proteins/genetics , Muscle Proteins/genetics , Phenotype , RNA, Antisense/pharmacology
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