This guide-a companion to the Radiation Oncology Self-Assessment Guide-is a comprehensive physics review for anyone in the field of radiation oncology looking to enhance their knowledge of medical ...physics. It covers in depth the principles of radiation physics as applied to radiation therapy along with their technical and clinical applications. To foster retention of key concepts and data, the resource utilizes a user-friendly "flash card" question and answer format with over 800 questions. The questions are supported by detailed answers and rationales along with reference citations for source information. The guide is comprised of 14 chapters that lead the reader through the radiation oncology physics field, from basic physics to current practice and latest innovations. Aspects of basic physics covered include fundamentals, photon and particle interactions, and dose measurement. A section on current practice covers treatment planning, safety, regulations, quality assurance, and SBRT, SRS, TBI, IMRT, and IGRT techniques. A chapter unique to this volume is dedicated to those topics in diagnostic imaging most relevant to radiology, including MRI, ultrasound, fluoroscopy, mammography, PET, SPECT, and CT. New technologies such as VMAT, novel IGRT devices, proton therapy, and MRI-guided therapy are also incorporated. Focused and authoritative, this must-have review combines the expertise of clinical radiation oncology and radiation physics faculty from the Cleveland Clinic Taussig Cancer Institute. Key Features: Includes more than 800 questions with detailed answers and rationales A one-stop guide for those studying the physics of radiation oncology including those wishing to reinforce their current knowledge of medical physics Delivered in a "flash card" format to facilitate recall of key concepts and data Presents a unique chapter on diagnostic imaging topics most relevant to radiation oncology Content provided by a vast array of contributors, including physicists, radiation oncology residents, dosimetrists, and physicians
In 1985, the Rockefeller Foundation published Good health at low cost to discuss why some countries or regions achieve better health and social outcomes than do others at a similar level of income ...and to show the role of political will and socially progressive policies. 25 years on, the Good Health at Low Cost project revisited these places but looked anew at Bangladesh, Ethiopia, Kyrgyzstan, Thailand, and the Indian state of Tamil Nadu, which have all either achieved substantial improvements in health or access to services or implemented innovative health policies relative to their neighbours. A series of comparative case studies (2009–11) looked at how and why each region accomplished these changes. Attributes of success included good governance and political commitment, effective bureaucracies that preserve institutional memory and can learn from experience, and the ability to innovate and adapt to resource limitations. Furthermore, the capacity to respond to population needs and build resilience into health systems in the face of political unrest, economic crises, and natural disasters was important. Transport infrastructure, female empowerment, and education also played a part. Health systems are complex and no simple recipe exists for success. Yet in the countries and regions studied, progress has been assisted by institutional stability, with continuity of reforms despite political and economic turmoil, learning lessons from experience, seizing windows of opportunity, and ensuring sensitivity to context. These experiences show that improvements in health can still be achieved in countries with relatively few resources, though strategic investment is necessary to address new challenges such as complex chronic diseases and growing population expectations.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Liver disease in the UK stands out as the one glaring exception to the vast improvements made during the past 30 years in health and life expectancy for chronic disorders such as stroke, heart ...disease, and many cancers. Mortality rates have increased 400% since 1970, and in people younger than 65 years have risen by almost five-times.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract Objective(s) To examine the association between obstructive sleep apnea (OSA) and other sleep indices using polysomnography (PSG) data and erectile dysfunction (ED) in a representative ...cohort of men. Design Cross-sectional. Setting Community-based. Participants Aged 40+ years (n = 734; mean age SD, 60.8 10.9). Measurements Men with no prior OSA diagnosis who underwent in-home PSG (Embletta X100; 2010-11) and ED assessment (Global Impotence Rating) were selected. Un-adjusted and multi-adjusted regression models of ED were fitted against PSG measures, along with qualifying sociodemographic, lifestyle, and health-related covariates. Mediation effects were examined using the Baron-Kenny method. Results Of the men examined, 24.7% (n = 181) had ED, most notably in men older than 65 years (cf. men 35-49 and 50-64years; P < .001). There was no significant association between ED and any of the PSG measures for allaged men. Given an observed ageinteraction within OSA categories ( P = .005), analyses were repeated in age-stratified samples (<65 years; 65+ years). In men younger than 65 years, only severe OSA was found to have an association with ED (2.01; 1.13-4.69) in unadjusted models. For men aged 65+ years, an independent association with ED was found for apnea-hyponea index (AHI; 1.55;1.02-2.36), moderate (AHI:10.0-19.9; 1.79;1.18-2.43), and severe (AHI:20.0+; 4.84;2.56-9.93) OSA, and oxygen desaturation index (ODI; both continuous 1.48;1.03-1.99 and >16 seconds 2.79;1.23-6.32). The effect of AHI on ED was shown to be primarily mediated through ODI (63.4%, Sobel P value = .29). Conclusions In younger, community-based men, there appeared no independent relationship between objective measures of sleep and ED. However, there appears a strong, independent relationship between OSA, ODI, and ED in men 65 years and older.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
AbstractContextPhysical activity for women with early-stage breast cancer is well recognized for managing cancer-related symptoms and improving quality of life. While typically excluded from ...interventions, women with metastatic breast cancer may also benefit from physical activity. ObjectiveTo 1) determine the safety and feasibility of a physical activity program for women with metastatic breast cancer and 2) explore the efficacy of the program. MethodsFourteen women with metastatic breast cancer were randomized to either a control group or an 8-week home-based physical activity intervention comprising twice weekly supervised resistance training and an unsupervized walking program. ResultsThe recruitment rate was 93%. Adherence to the resistance and walking components of the program was 100% and 25%, respectively. No adverse events were reported. When mean change scores from baseline to postintervention were compared, trends in favor of the exercise group over the control group were observed for the Functional Assessment of Chronic Illness Therapy-Fatigue score (+5.6 ± 3.2 vs. −1.8 ± 3.9, respectively), VO 2max (+1.6 ml/kg/minute ±1.8 mL/kg/minute vs. −0.2 mL/kg/minute ±0.1 mL/kg/minute, respectively) and six-minute walk test (+40 m ± 23 m vs. −46 m ± 56 m, respectively). ConclusionA partially supervised home-based physical activity program for women with metastatic breast cancer is feasible and safe. The dose of the resistance training component was well tolerated and achievable in this population. In contrast, adherence and compliance to the walking program were poor. Preliminary data suggest a physical activity program, comprising predominantly resistance training, may lead to improvements in physical capacity and may help women to live well with their disease.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
There is a known association between obstructive sleep apnea (OSA) and atrial fibrillation (AF); however, how OSA affects the atrial myocardium is not well described.
To determine whether patients ...with OSA have an abnormal atrial substrate.
Forty patients undergoing ablation of paroxysmal AF and in sinus rhythm (20 with OSA apnea-hypopnea index ≥ 15 and 20 reference patients with no OSA apnea-hypopnea index < 15 by polysomnography) were studied. Multipolar catheters were positioned at the lateral right atrium (RA), coronary sinus, crista terminalis, and RA septum to determine the effective refractory period at 5 sites, conduction time along linear catheters at the RA and the coronary sinus, conduction at the crista terminalis, and sinus node function (corrected sinus node recovery time). Biatrial electroanatomic maps were created to determine the voltage, conduction, and distribution of complex electrograms (duration ≥ 50 ms).
The groups had no differences in the prevalence of established risk factors for AF. Patients with OSA had the following compared with those without OSA: no difference in effective refractory period (P = .9), prolonged conduction times along the coronary sinus and RA (P = .02), greater number (P = .003) and duration (P = .03) of complex electrograms along the crista terminalis, longer P-wave duration (P = .01), longer corrected sinus node recovery time (P = .02), lower atrial voltage (RA, P <.001; left atrium, P <.001), slower atrial conduction velocity (RA, P = .001; left atrium, P = .02), and more widespread complex electrograms in both atria (RA, P = .02; left atrium, P = .01).
OSA is associated with significant atrial remodeling characterized by atrial enlargement, reduction in voltage, site-specific and widespread conduction abnormalities, and longer sinus node recovery. These features may in part explain the association between OSA and AF.
Background Evidence linking OSA with hypertension in population studies is conflicting. We examined longitudinal and cross-sectional associations of previously unrecognized OSA, including OSA ...occurring in rapid eye movement (REM) sleep, with hypertension. Methods The Men Androgens Inflammation Lifestyle Environment and Stress (MAILES) study is a longitudinal study of community-dwelling men in Adelaide, South Australia. Biomedical assessments at baseline (2002-2006) and follow-up (2007-2010) identified hypertension (systolic ≥ 140 mm Hg and/or diastolic ≥ 90 mm Hg, or medication) and risk factors. In 2010 to 2011, 837 men without a prior diagnosis of OSA underwent full in-home unattended polysomnography of whom 739 recorded ≥ 30 min of REM sleep. Hypertension at follow-up (concomitant with OSA status) was defined as prevalent hypertension. Recent-onset hypertension was defined as hypertension at biomedical follow-up (56 months mean follow-up range, 48-74) in men free of hypertension at baseline. Results Severe REM OSA (apnea hypopnea index ≥30/h) showed independent adjusted associations with prevalent (OR, 2.40, 95% CI, 1.42-4.06), and recent-onset hypertension (2.24 1.04-4.81). Significant associations with non-REM AHI were not seen. In men with AHI < 10, REM OSA (apnea hypopnea index) ≥ 20/h was significantly associated with prevalent hypertension (2.67 1.33-5.38) and the relationship with recent-onset hypertension was positive but not statistically significant (2.32 0.79-6.84). Similar results were seen when analyses were confined to men with non-REM AHI < 10. Conclusions In men not considered to have OSA (AHI < 10), hypertension was associated with OSA during REM sleep. REM OSA may need consideration as an important clinical entity requiring treatment but further systematic assessment and evidence is needed.
Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) often co-occur and share genetic risks. The aim of this analysis was to determine more broadly whether ADHD and ASD ...share biological underpinnings.
We compared copy number variant (CNV) data from 727 children with ADHD and 5,081 population controls to data from 996 individuals with ASD and an independent set of 1,287 controls. Using pathway analyses, we investigated whether CNVs observed in individuals with ADHD have an impact on genes in the same biological pathways as on those observed in individuals with ASD.
The results suggest that the biological pathways affected by CNVs in ADHD overlap with those affected by CNVs in ASD more than would be expected by chance. Moreover, this was true even when specific CNV regions common to both disorders were excluded from the analysis. After correction for multiple testing, genes involved in 3 biological processes (nicotinic acetylcholine receptor signalling pathway, cell division, and response to drug) showed significant enrichment for case CNV hits in the combined ADHD and ASD sample.
The results of this study indicate the presence of significant overlap of shared biological processes disrupted by large rare CNVs in children with these 2 neurodevelopmental conditions.
Summary Background Health-care workers have been implicated in nosocomial outbreaks of Staphylococcus aureus , but the dearth of evidence from non-outbreak situations means that routine health-care ...worker screening and S aureus eradication are controversial. We aimed to determine how often S aureus is transmitted from health-care workers or the environment to patients in an intensive care unit (ICU) and a high-dependency unit (HDU) where standard infection control measures were in place. Methods In this longitudinal cohort study, we systematically sampled health-care workers, the environment, and patients over 14 months at the ICU and HDU of the Royal Sussex County Hospital, Brighton, England. Nasal swabs were taken from health-care workers every 4 weeks, bed spaces were sampled monthly, and screening swabs were obtained from patients at admission to the ICU or HDU, weekly thereafter, and at discharge. Isolates were cultured and their whole genome sequenced, and we used the threshold of 40 single-nucleotide variants (SNVs) or fewer to define subtypes and infer recent transmission. Findings Between Oct 31, 2011, and Dec 23, 2012, we sampled 198 health-care workers, 40 environmental locations, and 1854 patients; 1819 isolates were sequenced. Median nasal carriage rate of S aureus in health-care workers at 4-weekly timepoints was 36·9% (IQR 35·7–37·3), and 115 (58%) health-care workers had S aureus detected at least once during the study. S aureus was identified in 8–50% of environmental samples. 605 genetically distinct subtypes were identified (median SNV difference 273, IQR 162–399) at a rate of 38 (IQR 34–42) per 4-weekly cycle. Only 25 instances of transmission to patients (seven from health-care workers, two from the environment, and 16 from other patients) were detected. Interpretation In the presence of standard infection control measures, health-care workers were infrequently sources of transmission to patients. S aureus epidemiology in the ICU and HDU is characterised by continuous ingress of distinct subtypes rather than transmission of genetically related strains. Funding UK Medical Research Council, Wellcome Trust, Biotechnology and Biological Sciences Research Council, UK National Institute for Health Research, and Public Health England.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Recreational drug use in men who have sex with men (MSM) is of concern because it might be linked to the transmission of HIV and other sexually transmitted infections. Evidence about drug use in ...HIV-diagnosed MSM in the UK is limited by representativeness of the study populations. We describe patterns of drug use and associations with sexual behaviours in HIV-diagnosed MSM in the UK.
We used data from the cross-sectional ASTRA study, which recruited participants aged 18 years or older with HIV from eight HIV outpatient clinics in the UK between Feb 1, 2011, and Dec 31, 2012. We examined data for MSM, assessing the prevalence of recreational drug use and polydrug use in the previous 3 months and associations with sociodemographic and HIV-related factors. We examined the association of polydrug use with measures of condomless sex in the previous 3 months and with other sexual behaviours.
Our analysis included data for 2248 MSM: 2136 (95%) were gay, 1973 (89%) were white, 1904 (85%) were on antiretroviral treatment (ART), and 1682 (76%) had a viral load of 50 copies per mL or lower. 1138 (51%) used recreational drugs in the previous 3 months; 608 (27%) used nitrites, 477 (21%) used cannabis, 460 (21%) used erectile dysfunction drugs, 453 (20%) used cocaine, 280 (13%) used ketamine, 258 (12%) used 3,4-methylenedioxy-N-methylamphetamine (MDMA), 221 (10%) used gamma-hydroxybutyrate or gamma-butyrolactone, 175 (8%) used methamphetamine, and 162 (7%) used mephedrone. In the 1138 individuals who used drugs, 529 (47%) used three or more drugs and 241 (21%) used five or more. Prevalence of injection drug use was 3% (n=68). Drug use was independently associated with younger age (p<0·0001), not being religious (p=0·001), having an HIV-positive stable partner (p=0·0008), HIV-serostatus disclosure (p=0·009), smoking (p<0·0001), evidence of harmful alcohol drinking (p=0·0001), and ART non-adherence (p<0·0001). Increasing polydrug use was associated with increasing prevalence of condomless sex (prevalence range from no drug use to use of five or more drugs was 24% to 78%), condomless sex with HIV-seroconcordant partners (17% to 69%), condomless sex with HIV-serodiscordant partners (10% to 25%), and higher-HIV-risk condomless sex after taking viral load into account (4% to 16%; p≤0·005 for all). Associations were similar after adjustment for sociodemographic and HIV-related factors. Methamphetamine was more strongly associated with higher-HIV-risk condomless sex than were other commonly used drugs.
Polydrug use is prevalent in HIV-diagnosed MSM and is strongly associated with condomless sex. Specialist support services for MSM with HIV who use recreational drugs might be beneficial in the reduction of harm and prevention of ongoing transmission of HIV and other sexually transmitted infections.
National Institute for Health Research.
PDF
