The effects of Chamomile tea on antioxidative biomarkers in operating room staff

Introduction: Chamomile tea (CT) is an herbal tea and is served as a beneficial herbal infusion all over the world. Its major polyphenols constituents and tea-catechins have been shown to have health benefits. Operating room staff are commonly exposed to damaging factors, such as radiation, waste anesthetic gases and psychological stress. One of the most important qualities of CT is its antioxidant property. The aim of this study was to evaluate the effects of CT in reducing the oxidative stress of operative room staff that are chronically exposed to damaging factors. Methods: In this study we approached to 20 operating room personnel. The subjects drank 2 cups of CT (every cup contained 1.8730 g of chamomile and 300 ml of water) daily, one cup in the morning and another in the afternoon for 21 days. A questionnaire that contained personal information was filled by each subject. Oxidative stress parameters such as total antioxidant capacity (TAC), catalase (CAT) and total thiol molecules (TTG) were measured 2 times: first before drinking CT at the first day and the next time after the 21st day. Results: Consumption of CT by subjects caused a significant induction in TAC (6.62 &plusmn; 0.77 vs 4.81&plusmn; 0.39 ųmol/ml, P &lt; .05) of saliva. There was not any statistically significant change in saliva TTG and CAT after 21 days of drinking CT. Conclusion: In the end we came to conclusion that CT can be a useful additional food to remove the oxidative damage that happens to operating room staff.</p

DMTTF-CA revisited: temperature-induced valence and structural instability

We report a detailed spectroscopic investigation of temperature-induced valence and structural instability of the mixed-stack organic charge-transfer (CT) crystal 4,4'-dimethyltetrathiafulvalene-chloranil (DMTTF-CA). DMTTF-CA is a derivative of tetrathiafulvalene-chloranil (TTF-CA), the first CT crystal exhibiting the neutral-ionic transition by lowering temperature. We confirm that DMTTF-CA undergoes a continuous variation of the ionicity on going from room temperature down to $\sim$ 20 K, but remains on the neutral side throughout. The stack dimerization and cell doubling, occurring at 65 K, appear to be the driving forces of the transition and of the valence instability. In a small temperature interval just below the phase transition we detect the coexistence of molecular species with slightly different ionicities. The Peierls mode(s) precursors of the stack dimerization are identified.Comment: 8 pages, 6 figures, Phys. Rev. B forma

A novel streamlined trauma response team training improves imaging efficiency for pediatric blunt abdominal trauma patients

Background/purpose The morbidity and mortality of children with traumatic injuries are directly related to the time to definitive management of their injuries. Imaging studies are used in the trauma evaluation to determine the injury type and severity. The goal of this project is to determine if a formal streamlined trauma response improves efficiency in pediatric blunt trauma by evaluating time to acquisition of imaging studies and definitive management. Methods This study is a chart review of patients < 18 years who presented to a pediatric trauma center following blunt trauma requiring trauma team activation. 413 records were reviewed to determine if training changed the efficiency of CT acquisition and 652 were evaluated for FAST efficiency. The metrics used for comparison were time from ED arrival to CT image, FAST, and disposition. Results Time from arrival to CT acquisition decreased from 37 (SD 23) to 28 (SD27) min (p < 0.05) after implementation. The proportion of FAST scans increased from 315 (63.5%) to 337 (80.8%) and the time to FAST decreased from 18 (SD15) to 8 (SD10) min (p < 0.05). The time to operating room (OR) decreased after implementation. Conclusion The implementation of a streamlined trauma team approach is associated with both decreased time to CT, FAST, OR, and an increased proportion of FAST scans in the pediatric trauma evaluation. This could result in the rapid identification of injuries, faster disposition from the ED, and potentially improve outcomes in bluntly injured children

Towards the production of radiotherapy treatment shells on 3D printers using data derived from DICOM CT and MRI: preclinical feasibility studies

Background: Immobilisation for patients undergoing brain or head and neck radiotherapy is achieved using perspex or thermoplastic devices that require direct moulding to patient anatomy. The mould room visit can be distressing for patients and the shells do not always fit perfectly. In addition the mould room process can be time consuming. With recent developments in three-dimensional (3D) printing technologies comes the potential to generate a treatment shell directly from a computer model of a patient. Typically, a patient requiring radiotherapy treatment will have had a computed tomography (CT) scan and if a computer model of a shell could be obtained directly from the CT data it would reduce patient distress, reduce visits, obtain a close fitting shell and possibly enable the patient to start their radiotherapy treatment more quickly. Purpose: This paper focuses on the first stage of generating the front part of the shell and investigates the dosimetric properties of the materials to show the feasibility of 3D printer materials for the production of a radiotherapy treatment shell. Materials and methods: Computer algorithms are used to segment the surface of the patient’s head from CT and MRI datasets. After segmentation approaches are used to construct a 3D model suitable for printing on a 3D printer. To ensure that 3D printing is feasible the properties of a set of 3D printing materials are tested. Conclusions: The majority of the possible candidate 3D printing materials tested result in very similar attenuation of a therapeutic radiotherapy beam as the Orfit soft-drape masks currently in use in many UK radiotherapy centres. The costs involved in 3D printing are reducing and the applications to medicine are becoming more widely adopted. In this paper we show that 3D printing of bespoke radiotherapy masks is feasible and warrants further investigation

Single institution implementation of permanent 131Cs interstitial brachytherapy for previously irradiated patients with resectable recurrent head and neck carcinoma

Purpose: Permanent interstitial brachytherapy is an appealing treatment modality for patients with locoregional recurrent, resectable head and neck carcinoma (HNC), having previously received radiation. Cesium-131 (131Cs) is a permanent implant brachytherapy isotope, with a low average photon energy of 30 keV and a short half-life of 9.7 days. Exposure to medical staff and family members is low; patient isolation and patient room shielding are not required. This work presents a single institution’s implementation process of utilizing an intraoperative, permanent 131Cs implant for patients with completely resected recurrent HNC. Materials & Methods: Fifteen patients receiving 131Cs permanent seed brachytherapy were included in this analysis. The process of pre-planning, selecting the dose prescription, seed ordering, intraoperative procedures, post-implant planning, and radiation safety protocols are described. Results: Tumor volumes were contoured on the available preoperative PET/CT scans and a pre-implant treatment plan was created using uniform source strength and uniform 1 cm seed spacing. Implants were performed intraoperatively, following tumor resection. In five of the fifteen cases, intraoperative findings necessitated a change from the planned number of seeds and recalculation of the pre-implant plan. The average prescription dose was 56.1 ±6.6 Gy (range, 40-60 Gy). The average seed strength used was 2.2 ±0.2 U (3.5 ±0.3 mCi). Patients returned to a recovery room on a standard surgical floor and remained inpatients, without radiation safety restrictions, based on standard surgical recovery protocols. A post-implant treatment plan was generated based on immediate post-operative CT imaging to verify the seed distribution and confirm delivery of the prescription dose. Patients were provided educational information regarding radiation safety recommendations. Conclusions: Cesium-131 interstitial brachytherapy is feasible and does not pose major radiation safety concerns; it should be considered as a treatment option for previously irradiated patients with recurrent, resectable HNC

Interplay of p-d and d-d charge transfer transitions in rare-earth perovskite manganites

We have performed both theoretical and experimental study of optical response of parent perovskite manganites RMnO_3 with a main goal to elucidate nature of clearly visible optical features. Starting with a simple cluster model approach we addressed the both one-center (p-d) and two-center (d-d) charge transfer (CT) transitions, their polarization properties, the role played by structural parameters, orbital mixing, and spin degree of freedom. Optical complex dielectric function of single crystalline samples of RMnO_3 (R=La, Pr, Nd, Sm, Eu) was measured by ellipsometric technique at room temperature in the spectral range from 1.0 to 5.0 eV for two light polarizations: E \parallel c and E \perp c. The comparative analysis of the spectral behavior of \varepsilon _1 and \varepsilon _2 is believed to provide a more reliable assignment of spectral features. We have found an overall agreement between experimental spectra and theoretical predictions based on the theory of one-center p-d CT transitions and inter-site d-d CT transitions. Our experimental data and theoretical analysis evidence a dual nature of the dielectric gap in nominally stoichiometric matrix of perovskite manganites RMnO_3, it is formed by a superposition of forbidden or weak dipole allowed p-d CT transitions and inter-site d-d CT transitions. In fact, the parent perovskite manganites RMnO_3 should rather be sorted neither into the CT insulator nor the Mott-Hubbard insulator in the Zaanen, Sawatzky, Allen scheme.Comment: 20 pages, 6 figure

The Use of a Novel Radiation Detector on Quantifying PET/Nuclear Medicine Occupational and Non-occupational Doses and Calibration of MOSFET Radiation Detectors against Effective Energy

Project 1: Dose reduction for PET technologists by the automatic dose draw/injection system* Purpose: To evaluate the dose reduction by the installed automatic dose draw/injection machine.* Materials & Methods: Six RadEye detectors were given to six PET technologists. A RadEye detector recorded data every 25 seconds throughout the day. Technologists logged their activities as follows: dose draw/injection, patient positioning, patient transport, patient care and non-specific. One technologist performed dose drawing/injection manually while others used the Trasis system. The Trasis machine was monitored with a Radeye detector during the period as well. * Results: The average dose reduction brought by Trasis is 75% for dose draw and 70% for dose injection. Qualitatively, instead of dose draw/injection, patient positioning has become the most significant contributing factor to overall PET technologist dose. In addition, the current average daily dose for a PET technologist is about 0.03 mSv, which on average is 36% less than before [12]. PET technologists typically received a dose of 0.007 mSv from dose draw/injection, 0.005 mSv from patient transport, 0.013 mSv from patient positioning, 0.001 mSv from patient care, and 0.003 mSv from non-specific per working day. This would result in an annual dose of 8 mSv which is approximately 16% of occupational dose limit (50 mSv).* Conclusions: The installation of automatic dose draw/injection machine has clear benefits to the PET technologists. The radiation doses for PET technologists are well within the annual limit of doses to occupational radiation workers. Project 2: Validation of ceiling shielding in CT/PET room with RADEYE* Purpose: To measure and the magnitude of scattered radiation levels in CT/PET suite and to evaluate the effectiveness of shielding of the ceiling. * Materials & Methods: Six RadEye detectors were placed in the CT/PET room, four in the ceiling, and two at one meter above floor. A RadEye detector recorded data every 25 seconds throughout the day. The detector was turned on at the beginning of the day (6 am) and the doses were transferred to a laptop for analysis at the end of the day (5 pm). The dose to a non-radiation worker above the CT/PET room was estimated based on the ceiling data. The magnitude of transmitted CT radiation in the room above was measured separately with RadEye.* Results: The CT dose contributed about 80% of the total dose while the PET contributed 20% within the scanning room. No dose contribution was measured above the floor from CT scanning. The combined dose from both PET and CT scan in a room above at 2.2 meter was 2.4x10-6 mSv per week, assuming an occupancy factor of 1. * Conclusions: This study quantified the CT and PET doses contributions separately in the clinical CT/PET room. An analytical model was developed to calculate the non-occupational personnel dose above the CT/PET room and the calculated results were confirmed by physical measurements. The actual physical dose was much smaller than the NCRP design goals of 0.02 mSv/wk.Project 3: Evaluating MOSFET dependency on effective energy over diagnostic energy range * Purpose: To characterize MOSFET calibration factors (CF) as a function of effective energy over diagnostic energy range.* Materials & Methods: Five new MOSFETs were used in the study. The calibration factors were measured in two ways: 1) fixed kVp, fixed SSD, fixed FOV, and varying filtration; and 2) fixed filtration, fixed SSD, fixed FOV, and varying kVp. Effective energy was computed as a function of kVp and filtration by SpekCalc.* Results: CF was independent with HVL in the range of HVL = 5 to HVL = 9mm Al at a fixed 120 kVp. CF depended linearly with kilo-voltage (kVp) from 80 to 140 kVp at a fixed filtration. In addition, a strong non-linear correlation of average CF versus effective energy was generated for effective energies in the diagnostic range (Goodness of fit of 0.98).* Conclusions: A correlation of second degree polynomial was seen between calibration factor and effective energy over diagnostic range. Hence, we created a calibration curve so that under a given fixed kVp or filtration, the calibration factor is automatically generated. A high correlation between CF versus effective energy was found over the diagnostic energy from 45 keV to 65 keV. This suggests that we could estimate the calibration factor with in-house generated MOSFET aging data, which would have a direct impacted CF linearly.</p