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Simple Summary: Accurate dose calculation and delivery is critical in treating cancers in radiation therapy. Although high accuracy has been achieved, significant uncertainties or errors still exist in radiation therapy, especially brachytherapy. Various types of uncertainty have been investigated, such as organ filling and organ motion. But interfraction dose variations (IDVs) from the prescribed dose in high dose rate brachytherapy (HDR) resulting from clinical considerations have not been widely discussed. Understanding what IDVs look like and whether or not they would affect clinical outcomes is important to improve the effectiveness of HDR brachytherapy and quality of cervical cancer treatment. We found IVDs followed a left-skewed distribution in our previous study, and we continued to discuss their potential effect on clinical outcomes in this project. In this study, we found that IDVs would reduce tumor control probability and increase treatment failure rate, but a dose escalation could be a remedy for such an effect. Meeting dose prescription is critical to control tumors in radiation therapy. Interfraction dose variations (IDVs) from the prescribed dose in high dose rate brachytherapy (HDR) would cause the target dose to deviate from the prescription but their clinical effect has not been widely discussed in the literature. Our previous study found that IDVs followed a left-skewed distribution. The clinical effect of the IDVs in 100 cervical cancer HDR patients will be addressed in this paper. An in-house Monte Carlo (MC) program was used to simulate clinical outcomes by convolving published tumor dose response curves with IDV distributions. The optimal dose and probability of risk-free local control (RFLC) were calculated using the utility model. The IDVs were well-fitted by the left-skewed Beta distribution, which caused a 3.99% decrease in local control probability and a 1.80% increase in treatment failure. Utility with respect to IDV uncertainty increased the RFLC probability by 6.70% and predicted an optimal dose range of 83 Gy–91 Gy EQD2. It was also found that a 10 Gy dose escalation would not affect toxicity. In conclusion, HRCTV IDV uncertainty reduced LC probabilities and increased treatment failure rates. A dose escalation may help mitigate such effects. [ABSTRACT FROM AUTHOR]

Purpose: The dosimetric effect of edema on prostate implants have long been realized, but large uncertainties still exist in the estimation of dose actually received by the prostate. This study attempted to develop a new method to accurately estimate dose delivered to the prostate accounting for the variation of prostate volume and seed distribution, edema half‐lives, and times for postimplant evaluation. Methods and materials: A series of prostate seed implants for Cs‐131, Pd‐103, and I‐125 with various prostate volumes were simulated in a water phantom using the TG‐43 algorithm on the Varian Eclipse treatment planning system. Dose analysis was performed to derive a quantitative relationship between the prostate peripheral dose and the prostate radius with the variation of prostate volume and seed distribution. Using this relationship to calculate dynamically, the total dose accumulated in the prostate (DT) accounting for the variation of prostate volume and seed distribution and edema half‐lives. Moreover, the total dose can be estimated statically based on the prostate volume that can be determined in a computerized tomography (CT) image taken at a time after implantation. The statically estimated total dose (DCT) was compared with DT to determine optimal imaging times as well as dose correction factors for other imaging times. Results: An inverse power law was established between the prostate peripheral dose and prostate radius. The value of the power was 1.3 for Cs‐131 and I‐125, and 1.5 for Pd‐103, respectively. DT was derived dynamically using the inverse power law. Given the edema half‐lives, TE, of 4, 9.3, and 25 days and the volume expansion of 1.1 and 2.0 times of the prostate without edema, the optimal times for postimplant imaging were: 7, 9, and 16 days for TE = 4 days; 10, 14, and 28 days for TE = 9.3 days; and 12, 19, 45 days TE = 25 days, for Cs‐131, Pd‐103, and I‐125, respectively. DCT calculated using the prostate volume determined on the optimal days agreed with DT to 0.0%–1.8% and within 0.3% for most cases. For various prostate volumes, edema half‐lives, and nonoptimal times, DCT was able to achieve a 1% accuracy. Conclusion: The postimplant dose calculation based on the proposed inverse power law for prostate seed implants with edema has improved the accuracy of postimplant dosimetry with accurate and patient‐specific dose corrections accounting for prostate size, edema half‐life, and postimplant imaging times. Optimal times for postimplant imaging have been accurately determined, and the high accuracy of postimplant dose calculation can be achieved for both optimal imaging times and nonoptimal imaging times. [ABSTRACT FROM AUTHOR]

The CivaSheet device uses multiple directionally shielded Pd-103 CivaDot sources to produce a directional planar dose distribution. In postplanning, manually digitizing the 3D source orientation is challenging because the 3D vector must be digitized by using 2D displayed images. The aim of this study is to develop an algorithm that will automatically determine the direction of each CivaDot source based on the location of sources adjacent to it. The algorithm determines the source direction by averaging the normal directions of multiple local planes established by the adjacent sources. The algorithm was tested on a manually constructed CivaSheet-like device that was CT scanned in known flat geometries and two known curved geometries. Algorithmically determined source directions were compared with the known directions. The algorithm was also used on a postplan for a gynecological pelvic sidewall tumor bed implant and compared against manual digitization of the source directions. For the flat and curved test geometries, the average angular difference between the algorithm determined and known orientation was 1.2° ± 0.8° (flat geometry), 1.7° ± 2.1° (curve about vertical axis), and 2.3° ± 2.4° (curve about horizontal axis). For the patient case, results showed on average a 23.1° ± 10.8° difference between the manual digitized orientation and the algorithm's predicted orientation. The algorithm calculates the source orientation with accuracy better than 2.3° for the controlled experiments. In addition to its accuracy, the algorithm produces consistent results and lessens the difficult challenge of orienting the partially shielded sources. [ABSTRACT FROM AUTHOR]

Purpose: To present a time-to-failure (TTF) analysis for all patients treated with permanent interstitial brachytherapy (PIB) at our institution, with additional analyses to correlate successful reirradiation and to identify the frequency of severe grade 3 to 4 toxicity.Methods and Materials: Forty-two previously irradiated patients received curative or palliative intent PIB for a recurrent pelvic malignancy between January 2009 and August 2016. Minimum follow-up was 6 months after the PIB procedure. All patients had a biopsy-proven recurrence and were treated using PIB alone (n=32) or in combination with a short course of additional radiation therapy (n=10). Competing risk analyses were performed to assess the risk of failures in the presence of death without failure. Exploratory analyses were performed for factors related to failure using competing risk analyses and the Gray statistic.Results: A total of 61 PIB implants were performed among 42 patients with a median follow-up of 16.3 months. Fifty-two implants were performed as the first salvage reirradiation to a solitary recurrence (8 patients had more than 1 lesion); the success rate for initial reirradiation using PIB was 73% (38 cases out of 52), and the median TTF was not reached. Nine patients underwent a second repeat PIB to the same recurrence as a form of salvage; 3 (33%) remain without evidence of recurrence. The median TTF after second salvage was 7.7 months. Even with the limited sample size, prolonged TTF was marginally associated with definitive intent (P=.07) and the extent of disease at the time of PIB (P=.08). Grade 3+ toxicities were seen in 8 patients (16.7%).Conclusions: Permanent interstitial brachytherapy is a feasible and potentially durable treatment modality that can be used to curatively salvage selected recurrent pelvic malignancies in a previously irradiated field. [ABSTRACT FROM AUTHOR]

Purpose This article aims to introduce the nurse to pharmacogenomics and its implications for clinical practice with regard to drug therapy. Organizing Constructs Pharmacogenomics is discussed with regard to the basic tenets, relationships to common health conditions, education and practice resources, and implications for nursing practice. Methods Peer-reviewed literature, websites, and expert professional guidelines were reviewed with relation to pharmacogenomics and nursing practice. Findings The genetic-genomic literature has grown significantly since the completion of the Human Genome Project in 2003. This information is now being translated into practice with regard to the patient's genetic profile and the impact on drug therapy, which is pharmacogenomics. Conclusions The utilization of the patient genetic-genomic profile is beginning to have an impact on patient drug therapy in clinical practice. Clinical Relevance Nurses are in the position to make sure, with the increased translation of pharmacogenomics into clinical practice, that adverse drug reactions are avoided and doses are optimized. [ABSTRACT FROM AUTHOR]

Sugammadex sodium is a modified y-cyclodextrin with a very high affinity for rocuronium and, to a lesser extent, vecuronium molecules. In vivo administration results in immediate encapsulation o f rocuronium and vecuronium, resulting in termination o f neuromuscular blockade, usually within 3 minutes. This new neuromuscular blocking agent is specific for the aminosteroidal neuromuscular blocking agents rocuronium and vecuronium. Experience gained through worldwide clinical use o f sugammadex offers US anesthesia providers the opportunity to better understand this new drug and its clinical applications. The seminal and current literature concerning clinical use o f sugammadex is reviewed, and considerations for its incorporation into practice are provided. [ABSTRACT FROM AUTHOR]

Abstract: The burden of orthostatic hypotension (OH) on public health is a universally recognized enigmatic clinical condition that is associated with significant increases on morbidity and mortality rates, and can take a major toll on one's quality of life. Orthostatic hypotension is predictive of vascular deaths from acute myocardial infarction, strokes in the middle aged population, and increases mortality rates when associated with diabetes, hypertension, Parkinson's disease, and patients receiving renal dialysis. The consensus definition for OH is a fall in systolic blood pressure of at least 20 mm Hg and/or diastolic blood pressure of at least 10 mm Hg within 3 minutes of quiet standing. Because neurogenic OH is often accompanied by supine hypertension, the treatment program should aim toward minimizing OH and the potential fall injuries related to cerebral hypoperfusion without exacerbating nocturnal hypertension that may lead to excessive cardiovascular complications. [Copyright &y& Elsevier]

The article offers information on how pharmacogenomics can aid nurses provide better care for patients. It illustrates an example of a lady aged 62 who experienced an acute myocardial infarction and was prescribed with genetic testing which resulted in better outcome. It discusses pharmacogenomic implications with warfarin drug, including antiplatelet therapy, mental health, human immunodeficiency virus (HIV) therapy, and oncology. Further discussed are limitations of genetic testing.

Sugammadex sodium is the generic drug name for the novelmodified gamma cyclodextrin that terminates neuromuscular blockade induced by aminosteroidal neuromuscular blocking agents. Published phase II and phase III clinical data support preclinical and clinical phase I study findings of fast, safe, and efficacious reversal of all levels of neuromuscular blockade induced by rocuronium and vecuronium. Low levels of neuromuscular blockade induced by pancuronium have also been successfully reversed by sugammadex. This agent does not reverse the bis-isoquinoline neuromuscular blocking agents. Special patient populations, including pediatric, elderly, cardiac, and renal-compromised subjects, have been studied in phase III. This update focuses on the most recent findings of phase II and III clinical studies. [ABSTRACT FROM AUTHOR]

The article reports that unstable angina (UA) and non-segment-elevation myocardial infarction (MI) make up a clinical syndrome subset of acute coronary syndromes. The identification and treatment of these conditions is important in reducing morbidity and mortality. UA and MI are associated with different degrees of ischemia. Patients with chest discomforts who go to the emergency department should undergo early risk stratification for cardiovascular events.

Helical tomotherapy is a technique for delivering intensity modulated radiation therapy treatments using a continuously rotating linac. In this approach, fan beams exiting the linac are dynamically modulated in synchrony with the motion of the gantry and couch. Helical IMRT deliveries have been applied to treating surface lesions, and the purpose of this study was to evaluate the accuracy of dose calculated by the TomoTherapy Hi·Art treatment planning system for superficial planning target volumes (PTVs). TomoTherapy treatment plans were developed for three superficial PTVs (2-, 4-, and 6-cm deep radially by 90° azimuthally by 4-cm longitudinally) contoured on a 27-cm diameter cylindrical white opaque, high-impact polystyrene phantom. The phantom included removable transverse and sagittal film cassettes that contained bare Kodak EDR2 films cut such that their edges matched the phantom surface (±0.05 cm). The phantom was aligned to the machine’s isocenter (±0.05 cm) and was irradiated according to the treatment plans. Films were scanned with a Vidar film digitizer, and optical densities were converted to dose using a calibration determined from a 6 MV perpendicular film exposure. This perpendicular calibration required that axial film doses (parallel irradiation) be scaled by 1.02 so that mid-arc depth doses matched those measured in the sagittal plane (perpendicular irradiation). All film readings were scaled by 0.935 to correct for over-response due to phantom Cerenkov light. Measured dose distributions were registered to calculated ones and compared. Calculated doses overpredicted measured doses by as much as 9.5% of the prescribed dose at depths less than 1 cm. At depths greater than 1 cm, calculated dose distributions showed agreement to measurement within 5% in the high-dose region and within 0.2 cm distance-to-agreement in the dose falloff regions. In the low-dose region posterior to the PTVs (<10% of the prescribed dose), the dose algorithm underpredicted the dose by 1%–2% of the prescribed dose. Clinically, it is recommended that 1 cm of bolus be used on the surface to ensure that cancerous tissues less than 1 cm depth are not underdosed. [ABSTRACT FROM AUTHOR]

The article highlights updated American Heart Association (AHA) guidelines for preventing cardiovascular disease (CVD) in women in the United States. The AHA suggeststhat comprehensive assessment and reduction of contributing factors can extend survival, improve quality of life, and reduce the incidence of subsequent coronary events. Lifestyle modifications are the foundation of preventing and managing diabetes, hypertension, dyslipidemia, and obesity.

Find out by reading this analysis of the new AHA guidelines for assessing and managing risk. [ABSTRACT FROM AUTHOR]

The article presents information about the diseases caused by endothelium and precautions to reduce the risk of endothelium. Earlier it was believed that hemoglobin inactivated nitric oxide but know that's not the case. The hemoglobin and nitric oxide have a mutually beneficial relationship. The hemoglobin picks up nitric oxide and carries it throughout the body. The nitric oxide's vasodilating action lets hemoglobin molecules pass through capillaries in the micro circulation that would normally be too small. The several precautions to reduce the risk of endothelium includes avoid smoking, high-sugar, high-fat diet and exercise regularly. INSET: Is your patient's endothelium healthy?.

Provides information on how to recognize heart disease in women and to help them get proper treatment. Factors that affect the risk of cardiovascular disease in women; Effort of the National Heart, Lung and Blood Institute of the U.S. Department of Health and Human Services and by the American Heart Association to increase awareness on heart disease in women; Heart disease treatment for women; Goals of cardiac rehabilitation. INSETS: THE HEART TRUTH;GO RED FOR WOMEN.

Reports that the National Heart, Lung, and Blood Institute is campaigning for women's self-empowerment to prevent heart disease by making information available about how to reduce and how to discuss testing or treatment with health care providers. Discussion of the similar risk factors of men and women for cardiovascular disease (CVD); Key factors affecting a woman's risk of CVD; Main goals of cardiac rehabilitation. INSETS: THE HEART TRUTH;GO RED FOR WOMEN.

Presents information on a study which examined the history of the discovery and identification of the roles played by adenyl purines in regulation of physiological homeostasis. Overview of purine synthesis; Review of related on adenyl purines; Role of adenosine triphosphate in coronary blood flow; Role of purines in neurotransmission; Other effects of adenyl purines.

Outlines some general considerations and examples of assessment measures regarding the study of science, technology and society (STS) in schools. Goals, curriculum and assessment in STS education; Open-ended assessment items for STS instruction; Performance-based assessment of STS education.

The article discusses psychological dimensions and research on love for neighbor and for God. The author agrees to Professor Alan C. Tjeltveit's contention that psychological boundaries are porous and that they have changed over time. He observes the cross-disciplinary efforts that make research rewarding and challenging. He believes on progress in applying skills, insights and skepticism on research about love of neighbor and God.

Simple Summary: The bodily response to cancer treatment is difficult to track in real time. This study aimed to demonstrate the possible application of magnetic resonance imaging (MRI) as a non-invasive and non-radiative modality to evaluate cancer response to therapy. We injected a fluorinated contrast agent in mouse models of breast and colon cancer to tag and track macrophages in real time. Longitudinal tracking of macrophages in tumors following radiation therapy via MRI provided a means of analyzing the tumor microenvironment without the need for a biopsy. It was shown that tumor-associated macrophage recruitment can be quantified through magnetic resonance imaging. Moreover, the findings suggest that macrophage response to radiation therapy is dependent on several factors including tumor origin. Since tumor recurrence following therapy is a major barrier following treatment, this imaging technique will be extremely beneficial in the future analysis of inflammation's role in that process. Background: Magnetic resonance imaging (MRI) is a non-invasive imaging modality which, in conjunction with biopsies, provide a qualitative assessment of tumor response to treatment. Intravenous injection of contrast agents such as fluorine (19F) nanoemulsions labels systemic macrophages, which can, then, be tracked in real time with MRI. This method can provide quantifiable insights into the behavior of tumor-associated macrophages (TAMs) in the tumor microenvironment and macrophage recruitment during therapy. Methods: Female mice received mammary fat pad injections of murine breast or colon cancer cell lines. The mice then received an intravenous 19F nanoemulsion injection, followed by a baseline 19F MRI. For each cancer model, half of the mice then received 8 Gy of localized radiation therapy (RT), while others remained untreated. The mice were monitored for two weeks for tumor growth and 9F signal using MRI. Results: Across both cohorts, the RT-treated groups presented significant tumor growth reduction or arrest, contrary to the untreated groups. Similarly, the fluorine signal in treated groups increased significantly as early as four days post therapy. The fluorine signal change correlated to tumor volumes irrespective of time. Conclusion: These results demonstrate the potential of 19F MRI to non-invasively track macrophages during radiation therapy and its prognostic value with regard to tumor growth. [ABSTRACT FROM AUTHOR]

The articles presents a safety checklist for reducing complications from surgery, as described by the World Health Organization (WHO) Second Global Patient Safety Challenge titled "Safe Surgery Saves Lives," which includes making sure the medical team is operating on the correct patient at the correct site, the use of methods known to prevent harm, and preparing for any life-threatening loss of respiratory function.

The article explains why knowledge of genetics and genomics is important for healthcare professionals. Topics discussed include how genomics and its associated technologies are changing the delivery of health care, the interchangeable usage of the terms pharmacogenetics and pharmacogenomics, and the vital role nurses will play in implementing the pharmacogenomics principles, reducing adverse drug reactions, and facilitating correct drug dosing.

The article focuses on the guideline entitled "2013 ACC/AHA Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults" of the American College of Cardiology and the American Heart Association on the risks of atherosclerotic cardiovascular disease (ASCVD). Topics discussed include the development of an online cardiovascular risk calculator by the guideline creator, randomized controlled trials on ASCVD, and the benefits of statin therapy.

High-sugar consumption is related to dyslipidemia. How acute exercise affects postprandial lipid and lipoprotein particle responses to a high-sugar meal (HSM) in postmenopausal women is unclear. We examined the effects of a late afternoon/early evening bout of aerobic exercise on postprandial lipid and lipoprotein particle responses to a HSM breakfast the following day in 22 postmenopausal women. Subjects underwent exercise (EX) and no exercise (NE) conditions in the evening 13–16 h before the HSM breakfast consumption, in a random order. During the EX condition, subjects performed supervised aerobic exercise for 60 min at 75% of age-predicted maximum heart rate. The HSM (75.6% carbohydrate and 33% energy needs) was consumed after a 12-h fast. Serum lipids and lipoproteins were assessed at baseline and postprandially (60, 120, 180 min). Repeated measures analysis showed significantly lower area under the curve (geometric means [95% CI]) for triglycerides (TG) (2.96[2.43, 3.61] vs. 3.24[2.70, 3.88] mmol/L*hr; p = 0.049) and very low density lipoprotein particles (VLDLP) (114.6[88.2, 148.9] vs. 134.3[108.1, 166.9] nmol/L*hr; p = 0.02) during the EX versus NE condition. There were no condition effects for other variables. In conclusion, the EX versus NE condition lowered postprandial AUC for TG and VLDLP following HSM consumption in postmenopausal women. Trial Registration: ClinicalTrials.gov Identifier: NCT02919488 [ABSTRACT FROM AUTHOR]

The article discusses research which was conducted to examine the influence resistance training (RT) had on inflammatory biomarkers in obese, postmenopausal women. Researchers evaluated 23 obese postmenopausal women who underwent a 12 week resistance training exercise program. They found that RT reduced markers of subclinical inflammation in circulation in obese, postmenopausal women in the absence of changes in body composition and that chronic RT also enhanced response to endotoxin challenge both at rest and 24 hours after an acute resistance exercise bout.

The purpose of this study was to determine whether resistance exercise training-induced reductions in inflammation are mediated via melanocortin 3 receptor expression in obese (BMI 32.7±3.7) women (65.6±2.8yrs) randomized to either a control (N = 11) or resistance training group (N = 12). The resistance trained group performed resistance training 3 days/week for 12 weeks. Resting blood samples were collected before and after the training intervention in both resistance trained and control groups. Resistance training upregulated melanocortin 3 receptor mRNA by 16-fold (P = .035) and decreased monocyte count, without changing leukocyte number, body composition, or body weight. Resistance trained individuals exhibited increased sensitivity to inflammatory stimuli, whereas control individuals exhibited no change.While there was no change in whole blood tumor necrosis factor alphamRNA between the groups, whole blood interleukin 10 mRNA was higher in the resistance trained group following the intervention period. In summary, it appears that resistance training may modulate melanocortin 3 receptor expression, providing a possible mechanism for the anti-inflammatory effects of exercise training. [ABSTRACT FROM AUTHOR]

Background and purpose: To evaluate the repositioning accuracy of a commercially available thermoplastic mask system for single dose radiosurgery treatments and fractionated treatment courses.Patients and methods: The repositioning accuracy of the Raycast©-HP mask system (Orfit Industries, Wijnegem, Belgium) was analyzed. Twenty-two patients that were treated by intensity-modulated radiation therapy (IMRT) or intensity modulated radiosurgery (IMRS) for 43 intracranial lesions, underwent repeated CT imaging during their course of treatment, or as a positional control immediately before radiosurgery. We evaluated multiple anatomical landmark coordinates and their respective shifts in consecutive repeated CT-controls. An iterative optimization algorithm allowed for the calculation of the x, y and z-components of translation of the target isocenter(s) for each repeated CT, as well as rotation in the respective CT data sets. In addition to absolute target isocenter translation, the total magnitude vector (i.e. sum-vector) of isocenter motion was calculated along with patient rotations about the three principle axes.Results: Fifty-five control CT datasets were analyzed for the target isocenter''s respective position relative to the original treatment planning CT simulation. Mean target isocenter translation was 0.74±0.53, 0.75±0.60 and 0.93±0.78 mm in x, y and z-directions, respectively. Mean rotation about the x, y and z-axes was 0.67±0.66, 0.61±0.63 and 0.67±0.61 degrees, respectively. The respective median and mean magnitude vectors of isocenter translation were 1.28 and 1.59±0.84 mm. Analysis of the accuracy of the first setup control, representative of setup accuracy for radiosurgery treatments, compared with setup accuracy throughout a fractionated radiation treatment course were statistically equivalent (P=0.15), thus indicating no measurable deterioration of setup accuracy throughout the treatment course.Conclusions: The analyzed Orfit thermoplastic mask system performed favorably compared with other mask immobilization systems for which peer-reviewed repositioning data exist. While the performance of the system for fractionated treatment courses was considered to be excellent, use of this mask system for radiosurgery immobilization in our clinic is subject to additional quality assurance measures to prohibit the delivery of treatments with target dislocations larger than 2 mm. The measured data in the present study should enable the users of this system to assign appropriate margins for the generation of planning target volumes. [Copyright &y& Elsevier]

Discusses the correlation of elevated homocysteine levels with increased risk for coronary artery disease (CAD). Metabolism of homocysteine; Effect of folic acid on total homocysteine levels; Results of interventional studies on homocysteine levels.

Early life stress increases one's risk for health problems later in life, and many studies find that these effects are sex-differentiated. Here, we examined relationships between multiple sources of early life stress and adult immune function in humans across several functional assays. Adult participants provided retrospective information about their childhood (a) socioeconomic status, (b) household unpredictability, and (c) exposure to adverse experiences. Participants' peripheral blood mononuclear cells (PBMCs) were then isolated for use in functional assays of immune performance: (a) tumor cell lysis by natural killer cells, (b) phagocytosis of Escherichia coli bioparticles, and (c) mitogen-induced leukocyte proliferation and cytokine release. In men, lower childhood socioeconomic status predicted decrements in immunological performance across functional assays, along with greater spontaneous cytokine release from PBMCs. These changes co-occurred with elevations in plasma testosterone levels. Similar effects were not observed for other sources of stress, nor were they found in women (with the exception of spontaneous cytokine release). These findings provide evidence that low childhood socioeconomic status has a lasting negative impact on multiple aspects of immune function, particularly in men. [ABSTRACT FROM AUTHOR]