Search

• Guidelines for the fabrication of custom molds using dental putty are provided. • Fundamental dosimetric characteristics of dental putty were measured using films. • High-dose-rate brachytherapy using dental putty-based custom mold is feasible. • Pretreatment dosimetry is desirable when dental putty mold is used. To investigate the feasibility of using dental putty to fabricate custom molds for high-dose-rate (HDR) brachytherapy of oral mucosal melanoma. Practical guidelines of using dental putty for the custom mold fabrication are presented. Dose measurements were performed using radiochromic films to understand the dosimetric characteristics of dental putty. The percentage depth dose (PDD) and profile curves were obtained using a single Co-60 source located on top of a cubic volume of the dental putty. Two custom molds were fabricated for a patient with mucosal melanoma lesions, which were spread throughout the right mandibular gingiva and soft palate regions. Furthermore, pretreatment dosimetry for both lesions was performed to evaluate the delivery quality of the resulting HDR brachytherapy plans and adjust the overall dose level. Prescribed doses for the two oral cavity regions were successfully delivered with a reasonable dose uniformity. Based on the measured single-source PDD curve, the maximum dose was observed at a depth of approximately 1 mm, which indicated steep dose gradients at depths ranging from 0 to 2 mm. Furthermore, a simulation with the measured single-source two-dimensional profile revealed that a source-to-source distance of 10 mm was appropriate to generate a uniform dose distribution at a source-to-surface distance of 5 mm. The use of a custom mold was found to be feasible for HDR brachytherapy while carefully considering the source-to-surface and source-to-source distances. Pretreatment delivery verification would be necessary when a uniform dose distribution is required. [ABSTRACT FROM AUTHOR]

Our purpose was to investigate the interfraction and intrafraction reproducibility and practical applicability of continuous positive airway pressure (CPAP) for left breast volumetric modulated arc therapy (VMAT). Interfraction reproducibility of the position of the heart was evaluated by measuring the heart-to-target distance on 20 planning computed tomography (CT) and 300 daily cone beam CT of 20 patients with left breast cancer treated with a 15-fraction VMAT. The dosimetric metrics of the whole heart and its substructures were compared between CPAP and free-breathing based VMAT plans. Intrafraction reproducibility was evaluated by measuring the motions of the breast target and diaphragm in 4-dimensional CT of 20 female patients with nonbreast cancer. Lastly, we analyzed the CPAP compliance data of 237 consecutive patients with left-sided breast cancer with and without internal mammary node irradiation (IMNI). The heart position was reproducible as evidenced by an absolute average heart-to-target distance error of 2.0 ± 2.0 mm. Compared with free-breathing, CPAP significantly reduced the mean heart dose and the dose to the left ventricle and left anterior descending artery. The average intrafraction position variation of the breast target was 0.5 ± 0.5, 2.5 ± 2.0, and 1.8 ± 1.4 mm in the mediolateral, craniocaudal, and anteroposterior directions, respectively. CPAP was successfully applied in 221 patients (93%), with a mean heart dose of 1.6 ± 0.7 Gy (IMNI: 2.0 Gy and no IMNI: 1.1 Gy). CPAP has adequate heart-sparing capability and sufficient reproducibility in VMAT for left-sided breast cancer treatment, with a high compliance rate. Thus, CPAP is applicable in routine practice for left-sided breast cancer radiation therapy. [ABSTRACT FROM AUTHOR]

Exercise-based cardiac rehabilitation (CR) is a class 1A recommendation for patients with cardiovascular disease (CVD). However, the reality is that the participation rate of CR in Korea is disastrously low. This study aimed to identify physical activity (PA) levels and to evaluate the preferences and barriers to exercise in patients with CVD. A total of 189 (143 males, 46 females) participants aged 19-75 years who had a history of either heart failure with reduced ejection fraction (HFrEF) or myocardial infarction (MI) were surveyed at an outpatient clinic in a single tertiary hospital from April to June 2021. Their demographic information, domain-specific PA levels (Global Physical Activity Questionnaire), sedentary time, exercise preferences, and exercise barriers were retrieved. Data on heart disease diagnosis and medical history of comorbidities were collected from electronic medical records. The participants' average age was 62 ± 12 years, where 84.7% accounted for HFrEF and 51.3% for MI. 63% of the participants were currently exercising, where those participating in any leisure PA was 43.4%, and those meeting the guideline (≥ moderate PA 150 mins/week) based on leisure PA was 26.5%. Exercising alone (43.5%) or with family (31.4%) was preferred to exercising with friends (11.6%), an expert (6.9%), CVD patients (2.1%), and others (3.7%). Exercising outside (37.0%) or at home (29.8%) was preferred to exercising at a fitness center (10.6%) or the hospital (0.5%). The participants chose walking (66.0%), resistance exercise (35.1%), overstretching (19.0%), and dancing (7.9%). The preferred amount of exercise was ≥30 mins/day (66%), and ≥4 times/week (52.4%). The most common exercise barriers were fatigue (34.0%), low level of fitness (28.5%), and poor self-perceived health (26.4%). The current study provided the PA status of CVD patients along with exercise preferences and barriers that will serve as valuable data for establishing CR programs that better encompass the needs of participants and increase the participation rate. [ABSTRACT FROM AUTHOR]

Abstract: Cu-doped Mg0.2Zn0.8O thin films were synthesized by sol–gel spin coating. We investigated the microstructural and optical characteristics of the Cu-doped Mg0.2Zn0.8O thin films. By increasing the Cu content of the source, Cu-doped Mg0.2Zn0.8O thin films were phase-separated into Cu-rich and Cu-poor areas, which could be a result of the limited Cu solubility in the Mg0.2Zn0.8O lattice. As the annealing temperature increased, the crystallinity of the Cu-doped Mg0.2Zn0.8O thin films improved. Cu doping in Mg0.2Zn0.8O thin films resulted in a decrease of both intensities for UV and visible emissions without a shift of the peak positions in the photoluminescence spectrum. [Copyright &y& Elsevier]

Abstract: In our previous study we demonstrated that acupuncture at Shenmen (HT7) points suppressed a decrease of accumbal dopamine (DA) release in ethanol-withdrawn rats. Furthermore, here we found that it inhibited behavioral withdrawal signs of ethanol. In an effort to better understand the mechanisms underlying this inhibition, the potential role of GABA receptor system in acupuncture was investigated. Male Sprague–Dawley rats were treated with 3g/kg/day of ethanol (20%, w/v) or saline by intraperitoneal injection for 21 days. Following 48 or 72h of ethanol withdrawal, acupuncture was applied at bilateral HT7 for 1min. The selective GABAA antagonist bicuculline and the selective GABAB antagonist SCH 50911 were injected intraperitoneally 20min before acupuncture, respectively. Importantly, suppressive effects of acupuncture on DA deficiency were completely abolished by SCH 50911, but not by bicuculline, whereas ameliorating effects of acupuncture on ethanol withdrawal syndrome were completely blocked either by SCH 50911 or bicuculline. These results suggest that acupuncture at specific acupoint HT7 may normalize the DA release in the mesolimbic system and attenuate withdrawal syndrome through the GABAB receptor system in ethanol-withdrawn rats. [Copyright &y& Elsevier]

Abstract: The mast cell-mediated immediate-type allergic reaction is involved in many allergic diseases such as asthma, allergic rhinitis and sinusitis. Stimulation of mast cells starts the process of degranulation resulting in release of mediators such as histamine and an array of inflammatory cytokines. In this report, we investigated the effect of aqueous extract of Amomum xanthiodes (Zingiberaceae) (AXE) on the mast cell-mediated allergy model and studied its possible mechanisms of action. AXE inhibited compound 48/80-induced systemic reactions and serum histamine release in mice. AXE decreased immunoglobulin E (IgE)-mediated passive cutaneous anaphylaxis reaction. AXE reduced histamine release and intracellular calcium from rat peritoneal mast cells activated by compound 48/80. Furthermore, AXE decreased the activation of p38 mitogen-activated protein kinase (MAPK) but not extracellular signal-regulated kinase and c-jun N-terminal kinase, and downstream tumor necrosis factor (TNF)-α production in phorbol 12-myristate 13-acetate and calcium ionophore A23187-stimulated human mast cells. Our findings provide evidence that AXE inhibits mast cell-derived allergic reactions, and that intracellular calcium, TNF-α, and p38 MAPK are involved in these effects. [Copyright &y& Elsevier]