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Sample records for clinical radiobiological experience

  1. Dosimetry for radiobiology experiments at GANIL

    NASA Astrophysics Data System (ADS)

    Durantel, Florent; Balanzat, Emmanuel; Cassimi, Amine; Chevalier, François; Ngono-Ravache, Yvette; Madi, Toiammou; Poully, Jean-Christophe; Ramillon, Jean-Marc; Rothard, Hermann; Ropars, Frédéric; Schwob, Lucas; Testard, Isabelle; Saintigny, Yannick

    2016-04-01

    Mainly encouraged by the increasing application of ion beams for cancer treatment (hadron-therapy) including carbon beams, the use of heavy ion facilities for radiobiology is expanding rapidly today. As an alternative to dedicated centers for treatment and medical research, accelerators like GANIL offer the possibility to undertake such experiments. Since 20 years, CIMAP, reinforced 15 years ago by the biological host laboratory LARIA, has been receiving researchers in radiobiology and assisted them in performing experiments in different fields such as hadron-therapy, space radioprotection and fundamental biological and physico-chemical mechanisms. We present here a short description of the beam line and the on-line equipments that allow the automatic irradiation of up to 24 biological samples at once. We also developed an original on-line beam monitoring procedure for low ion flux (low dose rates) based on the measurement of the K-shell X-rays emitted from a thin iron foil. This detector is calibrated on an absolute scale before each experiment by counting etched tracks on an irradiated CR39 polymer plate. We present the performances and limits of this method and finally give typical fluence (dose) uncertainties for a standard irradiation in radiobiology.

  2. Hypofractionation in prostate cancer: radiobiological basis and clinical appliance.

    PubMed

    Mangoni, M; Desideri, I; Detti, B; Bonomo, P; Greto, D; Paiar, F; Simontacchi, G; Meattini, I; Scoccianti, S; Masoni, T; Ciabatti, C; Turkaj, A; Serni, S; Minervini, A; Gacci, M; Carini, M; Livi, L

    2014-01-01

    External beam radiation therapy with conventional fractionation to a total dose of 76-80 Gy represents the most adopted treatment modality for prostate cancer. Dose escalation in this setting has been demonstrated to improve biochemical control with acceptable toxicity using contemporary radiotherapy techniques. Hypofractionated radiotherapy and stereotactic body radiation therapy have gained an increasing interest in recent years and they have the potential to become the standard of care even if long-term data about their efficacy and safety are not well established. Strong radiobiological basis supports the use of high dose for fraction in prostate cancer, due to the demonstrated exceptionally low values of α / β . Clinical experiences with hypofractionated and stereotactic radiotherapy (with an adequate biologically equivalent dose) demonstrated good tolerance, a PSA control comparable to conventional fractionation, and the advantage of shorter time period of treatment. This paper reviews the radiobiological findings that have led to the increasing use of hypofractionation in the management of prostate cancer and briefly analyzes the clinical experience in this setting. PMID:24999475

  3. Hypofractionation in Prostate Cancer: Radiobiological Basis and Clinical Appliance

    PubMed Central

    Mangoni, M.; Desideri, I.; Detti, B.; Bonomo, P.; Greto, D.; Paiar, F.; Simontacchi, G.; Meattini, I.; Scoccianti, S.; Masoni, T.; Ciabatti, C.; Turkaj, A.; Serni, S.; Minervini, A.; Gacci, M.; Carini, M.; Livi, L.

    2014-01-01

    External beam radiation therapy with conventional fractionation to a total dose of 76–80 Gy represents the most adopted treatment modality for prostate cancer. Dose escalation in this setting has been demonstrated to improve biochemical control with acceptable toxicity using contemporary radiotherapy techniques. Hypofractionated radiotherapy and stereotactic body radiation therapy have gained an increasing interest in recent years and they have the potential to become the standard of care even if long-term data about their efficacy and safety are not well established. Strong radiobiological basis supports the use of high dose for fraction in prostate cancer, due to the demonstrated exceptionally low values of α/β. Clinical experiences with hypofractionated and stereotactic radiotherapy (with an adequate biologically equivalent dose) demonstrated good tolerance, a PSA control comparable to conventional fractionation, and the advantage of shorter time period of treatment. This paper reviews the radiobiological findings that have led to the increasing use of hypofractionation in the management of prostate cancer and briefly analyzes the clinical experience in this setting. PMID:24999475

  4. In vitro irradiation system for radiobiological experiments

    PubMed Central

    2013-01-01

    Background Although two-dimensional (2-D) monolayer cell cultures provide important information on basic tumor biology and radiobiology, they are not representative of the complexity of three-dimensional (3-D) solid tumors. In particular, new models reproducing clinical conditions as closely as possible are needed for radiobiological studies to provide information that can be translated from bench to bedside. Methods We developed a novel system for the irradiation, under sterile conditions, of 3-D tumor spheroids, the in vitro model considered as a bridge between the complex architectural organization of in vivo tumors and the very simple one of in vitro monolayer cell cultures. The system exploits the same equipment as that used for patient treatments, without the need for dedicated and highly expensive instruments. To mimic the passage of radiation beams through human tissues before they reach the target tumor mass, 96-multiwell plates containing the multicellular tumor spheroids (MCTS) are inserted into a custom-built phantom made of plexiglass, the material most similar to water, the main component of human tissue. Results The system was used to irradiate CAEP- and A549-derived MCTS, pre-treated or not with 20 μM cisplatin, with a dose of 20 Gy delivered in one session. We also tested the same treatment schemes on monolayer CAEP and A549 cells. Our preliminary results indicated a significant increment in radiotoxicity 20 days after the end of irradiation in the CAEP spheroids pre-treated with cisplatin compared to those treated with cisplatin or irradiation alone. Conversely, the effect of the radio- chemotherapy combination in A549-derived MCTS was similar to that induced by cisplatin or irradiation alone. Finally, the 20 Gy dose did not affect cell survival in monolayer CAEP and A549 cells, whereas cisplatin or cisplatin plus radiation caused 100% cell death, regardless of the type of cell line used. Conclusions We set up a system for the irradiation

  5. In vitro irradiation station for broad beam radiobiological experiments

    NASA Astrophysics Data System (ADS)

    Wéra, A.-C.; Riquier, H.; Heuskin, A.-C.; Michiels, C.; Lucas, S.

    2011-12-01

    The study of the interaction of charged particles with living matter is of prime importance to the fields of radiotherapy, radioprotection and space radiobiology. Particle accelerators and their associated equipment are proven to be helpful tools in performing basic science in all these fields. Indeed, they can accelerate virtually any ions to a given energy and flux and let them interact with living matter either in vivo or in vitro. In this context, the University of Namur has developed a broad beam in vitro irradiation station for use in radiobiological experiments. Cells are handled in GLP conditions and can be irradiated at various fluxes with ions ranging from hydrogen to carbon. The station is mounted on a 2 MV tandem accelerator, and the energy range can be set up in the linear energy transfer (LET) ranges that are useful for radiobiological experiments. This paper describes the current status of the hardware that has been developed, and presents results related to its performance in term of dose-rate, energy range and beam uniformity for protons, alpha particles and carbon ions. The results of clonogenic assays of A549 lung adenocarcinoma cells irradiated with protons and alpha particles are also presented and compared with literature.

  6. Studies in the radiobiology of osteoradionecrosis and their clinical significance

    SciTech Connect

    Marx, R.E.; Johnson, R.P.

    1987-10-01

    The radiobiology of osteoradionecrosis is a complex of cellular death and cellular functional impairments from radiation energy transfers. Four studies of irradiated patients and a data base from 536 patients with osteoradionecrosis revealed separate pathophysiologic conditions for osteoradionecrosis induced by early trauma, osteoradionecrosis induced by late trauma, and spontaneous osteoradionecrosis. A large body of data suggested useful clinical guidelines for the management of irradiated patients. The guidelines, in part, include a recommendation for deferring radiation treatment for 21 days after tissue wounding, if possible; a relative contraindication to wounding tissue during a radiation course; a recommendation for the use of hyperbaric oxygen before wounding; and a strong recommendation to provide comprehensive dental care to the irradiated patient.

  7. Feasibility of BNCT radiobiological experiments at the HYTHOR facility

    NASA Astrophysics Data System (ADS)

    Esposito, J.; Ceballos, C.; Soncin, M.; Fabris, C.; Friso, E.; Moro, D.; Colautti, P.; Jori, G.; Rosi, G.; Nava, E.

    2008-06-01

    HYTHOR (HYbrid Thermal spectrum sHifter tapirO Reactor) is a new thermal-neutron irradiation facility, which was installed and became operative in mid 2005 at the TAPIRO (TAratura PIla Rapida potenza 0) fast reactor, in the Casaccia research centre (near Rome) of ENEA (Ente per le Nuove tecnologie Energia ed Ambiente). The facility has been designed for in vivo radiobiological studies. In HYTHOR irradiation cavity, 1-6 mice can be simultaneously irradiated to study skin melanoma treatments with the BNCT (boron neutron capture therapy). The therapeutic effects of HYTHOR radiation field on mouse melanoma has been studied as a preliminary investigation before studying the tumour local control due to boron neutron capture effect after boronated molecule injection. The method to properly irradiate small animals has been precisely defined. Results show that HYTHOR radiation field is by itself effective in reducing the tumour-growth rate. This finding has to be taken into account in studying the effectiveness of new 10B carriers. A method to properly measure the reduction of the tumour-growth rate is reported and discussed.

  8. Physical conditions for conducting radiobiological experiments in beams of accelerated particles with high linear energy transfer

    NASA Technical Reports Server (NTRS)

    Kudryashov, Y. I.; Marennyy, A. M.; Popov, V. I.; Aykhorn, K.; Ertsgreber, G.

    1974-01-01

    The design and construction of an accelerator to conduct radiobiological experiments is reported that uses aluminum filters to control the accelerated ion beam while preserving its stability, and a vacuum chamber to conduct the ion beam with the help of a collector through a lavsan exit port to the target. Depth distribution of the absorbed dose from a monodirectional ion beam is practically completely represented by the change in the energy spectrum of the biological object.

  9. [Radiobiological characteristics of chilled seedlings as an object for inflight experiments].

    PubMed

    Shaĭdorov, Iu I; Miller, A T; Fischere, G A

    1975-01-01

    It is recommended to use for experimentation cooled plant seedlings in the stage of delayed growth. Cooled seedlings have a high sensitivity to the environmental effects and can be used in long-term (up to 1-2 months) experiments. The influence of suboptimal temperatures on the radiosensitivity of seedlings, the development of radiation injury and maintenance of the radiobiological effect is described. PMID:1214486

  10. Preliminary analysis of a radiobiological experiment for LifeSat

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Townsend, Lawrence W.; Nealy, John E.; Hardy, Alva C.; Atwell, William; Schimmerling, Walter

    1991-01-01

    With the possibility of performing radiation life science experiments on a dedicated satellite (LifeSat) in space, a combined effort in radiation physics and radiation dosimetry, in addition to radiation biology, is clearly required to ensure that meaningful biological experiments can be performed. To better understand the relationship of these disciplines, some possible LifeSat missions are examined. As a trial biological system, tumorigenesis is considered in the Harderian gland of mice, a system of sufficient radiosensitivity for which relative biological effectiveness (RBE) is well defined by laboratory experiments.

  11. Radiobiological experiments with plant seeds aboard the biosatellite Kosmos 1887.

    PubMed

    Anikeeva, I D; Akatov YuA; Vaulina, E N; Kostina, L N; Marenny, A M; Portman, A I; Rusin, S V; Benton, E V

    1990-01-01

    The effects of spaceflight factors on the seeds of Arabidopsis thaliana and Crepis capillaris were studied provided with various protective measures: the seeds were located inside the satellite and in open space, protected with aluminium foil and also exposed without the foil cover. When the seeds were in open space without any protection, their viability was found to be suppressed; the survival rate and fertility of plants grown from these seeds were also diminished. An increase in the frequency of chromosome aberrations (CA) and in the number of multiple injuries was registered in this case. Experiments with the aluminium foil shielding showed a decrease in the suppression of the seeds' viability, but mutational changes were found to be even more increased, while the survival and fertility of the plants decreased. An increase in the thickness of shielding resulted in a decrease in the effects up to the level of the control, except for the effects connected with CA and fertility of the plants. Analysis of the results shows that these impairments can be ascribed to the action of single heavy charged particles (HCP). The seeds can be thus regarded as an integral biological 'dosimeter' which allows estimation of the total effects of radiation, ecological and biological factors. PMID:11537516

  12. Radiobiological experiments with plant seeds aboard the biosatellite Cosmos 1887

    NASA Technical Reports Server (NTRS)

    Benton, E. V.; Anikeeva, I. D.; Akatov, Yu. A.; Vaulina, E. N.; Kostina, L. N.; Marenny, A.; Portman, A. I.; Rusin, S. V.

    1995-01-01

    The effects of spaceflight factors on the seeds of Arabidopsis thaliana and Crepis capillaris were studied. The seeds were located inside the satellite in an open space, protected with aluminum foil and also exposed without the foil cover. When the seeds were in open space without any protection, their viability was found to be suppressed; the survival rate and fertility of plants grown from these seeds were also diminished. An increase in the frequency of chromosome aberrations (CA) and in the number of multiple injuries was registered in this case. Experiments with the aluminum foil shielding showed a decrease in the suppression of the seeds' viability, but mutational changes were found to be even more increased, while the survival rate and fertility of the plants decreased. An increase in the thickness of shielding resulted in a decrease in the effects up to the level of the control, except for the effects connected with CA and fertility of the plants. Analysis of the results shows that these impairments can be ascribed to the action of single heavy charged particles (HCP). The seeds can thus be regarded as an integral biological 'dosimeter' which allows estimation of the total effects of radiation, ecological and biological factors.

  13. Radiobiological experiments with plant seeds aboard the biosatellite Kosmos 1887

    NASA Technical Reports Server (NTRS)

    Anikeeva, I. D.; Vaulina, E. N.; Kostina, L. N.; Marenny, A. M.; Portman, A. I.; Rusin, S. V.; Benton, E. V.

    1990-01-01

    The effects of spaceflight factors on the seeds of Arabidopsis thaliana and Crepis capillaris were studied provided with various protective measures: the seeds were located inside the satellite and in open space, protected with aluminium foil and also exposed without the foil cover. When the seeds were in open space without any protection, their viability was found to be suppressed; the survival rate and fertility of plants grown from these seeds were also diminished. An increase in the frequency of chromosome aberrations (CA) and in the number of multiple injuries was registered in this case. Experiments with the aluminium foil shielding showed a decrease in the suppression of the seeds' viability, but mutational changes were found to be even more increased, while the survival and fertility of the plants decreased. An increase in the thickness of shielding resulted in a decrease in the effects up to the level of the control, except for the effects connected with CA and fertility of the plants. Analysis of the results shows that these impairments can be ascribed to the action of single heavy charged particles (HCP). The seeds can be thus regarded as an integral biological 'dosimeter' which allows estimation of the total effects of radiation, ecological and biological factors.

  14. Analysis of a large number of clinical studies for breast cancer radiotherapy: estimation of radiobiological parameters for treatment planning

    NASA Astrophysics Data System (ADS)

    Guerrero, M.; Li, X. Allen

    2003-10-01

    Numerous studies of early-stage breast cancer treated with breast conserving surgery (BCS) and radiotherapy (RT) have been published in recent years. Both external beam radiotherapy (EBRT) and/or brachytherapy (BT) with different fractionation schemes are currently used. The present RT practice is largely based on empirical experience and it lacks a reliable modelling tool to compare different RT modalities or to design new treatment strategies. The purpose of this work is to derive a plausible set of radiobiological parameters that can be used for RT treatment planning. The derivation is based on existing clinical data and is consistent with the analysis of a large number of published clinical studies on early-stage breast cancer. A large number of published clinical studies on the treatment of early breast cancer with BCS plus RT (including whole breast EBRT with or without a boost to the tumour bed, whole breast EBRT alone, brachytherapy alone) and RT alone are compiled and analysed. The linear quadratic (LQ) model is used in the analysis. Three of these clinical studies are selected to derive a plausible set of LQ parameters. The potential doubling time is set a priori in the derivation according to in vitro measurements from the literature. The impact of considering lower or higher Tpot is investigated. The effects of inhomogeneous dose distributions are considered using clinically representative dose volume histograms. The derived LQ parameters are used to compare a large number of clinical studies using different regimes (e.g., RT modality and/or different fractionation schemes with different prescribed dose) in order to validate their applicability. The values of the equivalent uniform dose (EUD) and biologically effective dose (BED) are used as a common metric to compare the biological effectiveness of each treatment regime. We have obtained a plausible set of radiobiological parameters for breast cancer: agr = 0.3 Gy-1, agr/bgr = 10 Gy and sub

  15. Development of a compact laser-produced plasma soft X-ray source for radiobiology experiments

    NASA Astrophysics Data System (ADS)

    Adjei, Daniel; Ayele, Mesfin Getachew; Wachulak, Przemyslaw; Bartnik, Andrzej; Wegrzynski, Łukasz; Fiedorowicz, Henryk; Vyšín, Luděk; Wiechec, Anna; Lekki, Janusz; Kwiatek, Wojciech M.; Pina, Ladislav; Davídková, Marie; Juha, Libor

    2015-12-01

    A desk-top laser-produced plasma (LPP) source of soft X-rays (SXR) has been developed for radiobiology research. The source is based on a double-stream gas puff target, irradiated with the focused beam of a commercial Nd:YAG laser. The source has been optimized to get a maximum photon emission from LPP in the X-ray "water window" spectral wavelength range from 2.3 nm (i.e., an absorption edge of oxygen) to 4.4 nm (i.e., an absorption edge of carbon) (280-540 eV in photon energy units) by using argon gas-puff target and spectral filtering by free-standing thin foils. The present source delivers nanosecond pulses of soft X-rays at a fluence of about 4.2 × 103 photons/μm2/pulse on a sample placed inside the vacuum chamber. In this paper, the source design, radiation output characterization measurements and initial irradiation experiments are described. The source can be useful in addressing observations related to biomolecular, cellular and organisms' sensitivity to pulsed radiation in the "water window", where carbon atoms absorb X-rays more strongly than the oxygen, mostly present in water. The combination of the SXR source and the radiobiology irradiation layout, reported in this article, make possible a systematic investigation of relationships between direct and indirect action of ionizing radiation, an increase of a local dose in carbon-rich compartments of the cell (e.g., lipid membranes), an experimental estimation of a particular role of the Auger effect (in particular in carbon atoms) in the damage to biological systems, and the study of ionization/excitation-density (LET - Linear Energy Transfer) and dose-rate effects in radiobiology.

  16. Studies of SSNTDs made from LR-115 in view of their applicability in radiobiological experiments with alpha particles

    NASA Astrophysics Data System (ADS)

    Dörschel, B.; Hermsdorf, D.; Pieck, S.; Starke, S.; Thiele, H.; Weickert, F.

    2003-06-01

    Radiobiological studies on cell monolayers irradiated by charged particles need to determine the number and position of particle traversals. Solid state nuclear track detectors used as basic substrate for the cell layers are in principle suitable for this purpose. The detector foils must be as thin as possible but still guaranteeing mechanical stability. Two types of LR-115, red coloured and colourless, were tested in the present work. The studies aimed at optimisation of the etching conditions and determination of the registration efficiency for alpha particles in a wide range of energies and angles of incidence. Specific requirements have to be fulfilled for application of the detector foils under the environmental conditions of radiobiological experiments. Most important are biocompatibility between detector and cells and registration properties insensible against special treatments, as UV sterilisation and cell plating prior to irradiation as well as cell incubation after the irradiation. The experimental studies performed with alpha particles showed that environmental conditions of radiobiological experiments do not change the registration properties of LR-115 detectors significantly.

  17. Automation of the particle dosimetry and the dose application for radiobiological experiments at a vertical proton beam

    NASA Astrophysics Data System (ADS)

    Mörtel, H.; Georgi, J.; Eyrich, W.; Fritsch, M.; Distel, L.

    2002-08-01

    A facility with a vertical beam for radiobiological experiments with low-energy protons has been setup at the Tandem accelerator at Erlangen. This energy region is optimal to investigate the biological effects of the linear energy transfer in the Bragg region under physiological conditions. A new automated data acquisition system for dosimetry and monitoring based on a personal computer was developed and optimized for this setup. A specially designed sample holder offers possibilities of cooling or changing of atmosphere during irradiation. First irradiations of biological samples have shown the functionality of the setup.

  18. The new hybrid thermal neutron facility at TAPIRO reactor for BNCT radiobiological experiments.

    PubMed

    Esposito, J; Rosi, G; Agosteo, S

    2007-01-01

    A new thermal neutron irradiation facility, devoted to carry out both dosimetric and radiobiological studies on boron carriers, which are being developed in the framework of INFN BNCT project, has been installed at the ENEA Casaccia TAPIRO research fast reactor. The thermal column, based on an original, hybrid, neutron spectrum shifter configuration, has been recently become operative. In spite of its low power (5 kW), the new facility is able to provide a high thermal neutron flux level, uniformly distributed inside the irradiation cavity, with a quite low gamma background. The main features and preliminary benchmark measurements of the Beam-shaping assembly are here presented and discussed. PMID:17504745

  19. Determination of radiobiological parameters for the safe clinical application of BNCT

    SciTech Connect

    Hopewell, J.W.; Morris, G.M.; Coderre, J.A.

    1993-12-31

    In the present report the effects of BNCT irradiation on the skin and spinal cord of Fischer 344 rats, for known concentrations of {sup 10}B in the blood and these normal tissues, are compared with the effects of the neutron beam alone or photon irradiation. The biological effectiveness of irradiation in the presence of the capture agents BSH and BPA have been compared. Irradiations were carried out using the thermal beam of the Brookhaven Medical Research Reactor (BMRR). Therapy experiments were also carried out as part of this study, using the rat 9L-gliosarcoma cell line, in order to establish the potential therapeutic advantage that might be achieved using the above capture agents. This cell line grows as a solid tumor in vivo as well as in vitro. The implications of these findings, with respect to the clinical use of the Petten HBII based epithermal neutron beam, will be discussed.

  20. Future treatment directions for HPV-associated head and neck cancer based on radiobiological rationale and current clinical evidence.

    PubMed

    Marcu, Loredana G

    2016-07-01

    A relatively new entity of head and neck squamous cell carcinoma located in the oropharynx and associated to the human papillomavirus (HPV) is on the rise. This cancer represents a distinct entity from the non-HPV tumours, holds different biological characteristics and responds differently to treatment. An outcome analysis of locoregionally-advanced oropharyngeal versus non-oropharyngeal cancers treated with chemo-radiotherapy revealed a statistically significant improvement for oropharyngeal cancers, which are thought to be due to their HPV-association. Consequently, more attention is paid to HPV-related head and neck cancers, given that HPV status serves as prognostic marker in oropharyngeal cancer patients. Yet, HPV positivity is a simplistic approach for risk stratification, thus more robust biomarkers are needed to fulfil this task. Despite differences in clinical response, HPV-related oral cancers undergo similar therapy to their non-HPV counterparts. This review discusses future treatment directions for HPV-related oropharyngeal cancers based on radiobiological rationale and current clinical evidence. PMID:27221393

  1. Transformation of Physical DVHs to Radiobiologically Equivalent Ones in Hypofractionated Radiotherapy Analyzing Dosimetric and Clinical Parameters: A Practical Approach for Routine Clinical Practice in Radiation Oncology

    PubMed Central

    Thrapsanioti, Zoi; Karanasiou, Irene; Platoni, Kalliopi; Efstathopoulos, Efstathios P.; Matsopoulos, George; Dilvoi, Maria; Patatoukas, George; Chaldeopoulos, Demetrios; Kelekis, Nikolaos; Kouloulias, Vassilis

    2013-01-01

    Purpose. The purpose of this study was to transform DVHs from physical to radiobiological ones as well as to evaluate their reliability by correlations of dosimetric and clinical parameters for 50 patients with prostate cancer and 50 patients with breast cancer, who were submitted to Hypofractionated Radiotherapy. Methods and Materials. To achieve this transformation, we used both the linear-quadratic model (LQ model) and the Niemierko model. The outcome of radiobiological DVHs was correlated with acute toxicity score according to EORTC/RTOG criteria. Results. Concerning the prostate radiotherapy, there was a significant correlation between RTOG acute rectal toxicity and D50 (P < 0.001) and V60 (P = 0.001) dosimetric parameters, calculated for α/β = 10 Gy. Moreover, concerning the breast radiotherapy there was a significant correlation between RTOG skin toxicity and V≥60 dosimetric parameter, calculated for both α/β = 2.3 Gy (P < 0.001) and α/β = 10 Gy (P < 0.001). The new tool seems reliable and user-friendly. Conclusions. Our proposed model seems user-friendly. Its reliability in terms of agreement with the presented acute radiation induced toxicity was satisfactory. However, more patients are needed to extract safe conclusions. PMID:24348743

  2. Enhanced radiobiological effects at the distal end of a clinical proton beam: in vitro study

    PubMed Central

    Matsumoto, Yoshitaka; Matsuura, Taeko; Wada, Mami; Egashira, Yusuke; Nishio, Teiji; Furusawa, Yoshiya

    2014-01-01

    In the clinic, the relative biological effectiveness (RBE) value of 1.1 has usually been used in relation to the whole depth of the spread-out Bragg-peak (SOBP) of proton beams. The aim of this study was to confirm the actual biological effect in the SOBP at the very distal end of clinical proton beams using an in vitro cell system. A human salivary gland tumor cell line, HSG, was irradiated with clinical proton beams (accelerated by 190 MeV/u) and examined at different depths in the distal part and the center of the SOBP. Surviving fractions were analyzed with the colony formation assay. Cell survival curves and the survival parameters were obtained by fitting with the linear–quadratic (LQ) model. The RBE at each depth of the proton SOBP compared with that for X-rays was calculated by the biological equivalent dose, and the biological dose distribution was calculated from the RBE and the absorbed dose at each position. Although the physical dose distribution was flat in the SOBP, the RBE values calculated by the equivalent dose were significantly higher (up to 1.56 times) at the distal end than at the center of the SOBP. Additionally, the range of the isoeffective dose was extended beyond the range of the SOBP (up to 4.1 mm). From a clinical point of view, this may cause unexpected side effects to normal tissues at the distal position of the beam. It is important that the beam design and treatment planning take into consideration the biological dose distribution. PMID:24824674

  3. Radiobiological results from the Bacillus subtilis Biostack experiments within the Apollo and the ASTP space flights.

    PubMed

    Facius, R; Bucker, H; Hildebrand, D; Horneck, G; Holtz, G; Reitz, G; Schafer, M; Toth, B

    1978-01-01

    In order to check the results of earlier Biostack experiments, new experimental techniques were developed for the Biostack III experiment in the Apollo-Soyuz test project (ASTP). These techniques resulted in an increased accuracy of localization down to 0.2 micrometers for the determination of the impact parameter, accompanied by an increase in the sample size available for biological investigation. In addition, colony forming ability, metabolic mutations, and mutations affecting UV- and x-ray sensitivity were rendered observable by these methods. The biological and physical results obtained so far from the evaluation of the Bacillus subtilis experiment within Biostack III confirm and extend the findings of the previous Biostack experiments. They also add to the questions about the mechanisms of action of the radiation field under investigation, since the observed effects cannot be interpreted in terms of standard concepts. PMID:11965659

  4. SU-E-J-233: A Facility for Radiobiological Experiments in a Large Magnetic Field

    SciTech Connect

    Carlone, M; Heaton, R; Keller, H; Wouters, B; Jaffray, D

    2014-06-01

    Purpose: There is considerable interest in developing medical linear accelerators with integrated image guidance by MRI. Less work has been done on the fundamental biology of cell survival in the presence of a strong magnetic field. The purpose of this work is to describe an experimental system capable of measuring cell survival response in the types of MRI-linac systems currently under development. Methods: We have integrated a cobalt irradiator with a solenoid magnet. The solenoid magnet has inner diameter of 10 cm. To enable measurement of the biological effects as a function of depth, we are utilizing the sliced gel technique, in which cells are embedded and fixed within a gelatin matrix. Irradiated cells at defined positions (sub mm resolution) can subsequently be recovered and assessed for cell survival or other biological effects. Results: The magnetic field profile in the solenoid has a peak magnetic field 36 cm below the top edge of the magnet bore and can be placed at and SAD of 100 cm. At a solenoid current of 35 A, the peak magnetic field is 0.25 T. The dose rate of the cobalt irradiator is 16 cGy/min at 100 cm SAD. EBT3 film was used to demonstrate the system functionality. It was irradiated at 1 cm depth at 100 cm SSD with a 4×4 field to 1.5 Gy in a 0.25 T magnetic field. The dose profile was similar between this film and the control exposure without magnetic field. Conclusion: Integrating a cobalt irradiator with a high field magnet is demonstrated. The magnetic field at the cobalt defining head was minimal and did not interfere with the functioning of this unit. Cell survival experiments can be reproduced exactly in the presence or absence of a magnetic field since a resistive magnet is used.

  5. Non-extensive radiobiology

    NASA Astrophysics Data System (ADS)

    Sotolongo-Grau, O.; Rodriguez-Perez, D.; Antoranz, J. C.; Sotolongo-Costa, O.

    2011-03-01

    The expression of survival factors for radiation damaged cells is based on probabilistic assumptions and experimentally fitted for each tumor, radiation and conditions. Here we show how the simplest of these radiobiological models can be derived from the maximum entropy principle of the classical Boltzmann-Gibbs expression. We extend this derivation using the Tsallis entropy and a cutoff hypothesis, motivated by clinical observations. A generalization of the exponential, the logarithm and the product to a non-extensive framework, provides a simple formula for the survival fraction corresponding to the application of several radiation doses on a living tissue. The obtained expression shows a remarkable agreement with the experimental data found in the literature, also providing a new interpretation of some of the parameters introduced anew. It is also shown how the presented formalism may have direct application in radiotherapy treatment optimization through the definition of the potential effect difference, simply calculated between the tumour and the surrounding tissue.

  6. Non-extensive radiobiology

    SciTech Connect

    Sotolongo-Grau, O.; Rodriguez-Perez, D.; Antoranz, J. C.; Sotolongo-Costa, O.

    2011-03-14

    The expression of survival factors for radiation damaged cells is based on probabilistic assumptions and experimentally fitted for each tumor, radiation and conditions. Here we show how the simplest of these radiobiological models can be derived from the maximum entropy principle of the classical Boltzmann-Gibbs expression. We extend this derivation using the Tsallis entropy and a cutoff hypothesis, motivated by clinical observations. A generalization of the exponential, the logarithm and the product to a non-extensive framework, provides a simple formula for the survival fraction corresponding to the application of several radiation doses on a living tissue. The obtained expression shows a remarkable agreement with the experimental data found in the literature, also providing a new interpretation of some of the parameters introduced anew. It is also shown how the presented formalism may have direct application in radiotherapy treatment optimization through the definition of the potential effect difference, simply calculated between the tumour and the surrounding tissue.

  7. The radiobiology of hypofractionation.

    PubMed

    Nahum, Alan E

    2015-05-01

    If the α/β ratio is high (e.g. 10 Gy) for tumour clonogen killing, but low (e.g. 3 Gy) for late normal tissue complications, then delivering external beam radiotherapy in a large number (20-30) of small (≈2 Gy) dose fractions should yield the highest 'therapeutic ratio'; this is demonstrated via the linear-quadratic model of cell killing. However, this 'conventional wisdom' is increasingly being challenged, partly by the success of stereotactic body radiotherapy (SBRT) or stereotactic ablative radiotherapy (SABR) extreme hypofractionation regimens of three to five large fractions for early stage non-small cell lung cancer and partly by indications that for certain tumours (prostate, breast) the α/β ratio may be of the same order or even lower than that characterising late complications. It is shown how highly conformal dose delivery combined with quasi-parallel normal tissue behaviour (n close to 1) enables 'safe' hypofractionation; this can be predicted by the (α/β)eff concept for normal tissues. Recent analyses of the clinical outcomes of non-small cell lung cancer radiotherapy covering 'conventional' hyper- to extreme hypofractionation (stereotactic ablative radiotherapy) regimens are consistent with linear-quadratic radiobiology, even at the largest fraction sizes, despite there being theoretical reasons to expect 'LQ violation' above a certain dose. Impairment of re-oxygenation between fractions and the very high (α/β) for hypoxic cells can complicate the picture regarding the analysis of clinical outcomes; it has also been suggested that vascular damage may play a role for very large dose fractions. Finally, the link between high values of (α/β)eff and normal-tissue sparing for quasi-parallel normal tissues, thereby favouring hypofractionation, may be particularly important for proton therapy, but more generally, improved conformality, achieved by whatever technique, can be translated into individualisation of both prescription dose and fraction

  8. Introduction to Radiobiology of Targeted Radionuclide Therapy

    PubMed Central

    Pouget, Jean-Pierre; Lozza, Catherine; Deshayes, Emmanuel; Boudousq, Vincent; Navarro-Teulon, Isabelle

    2015-01-01

    During the last decades, new radionuclide-based targeted therapies have emerged as efficient tools for cancer treatment. Targeted radionuclide therapies (TRTs) are based on a multidisciplinary approach that involves the cooperation of specialists in several research fields. Among them, radiobiologists investigate the biological effects of ionizing radiation, specifically the molecular and cellular mechanisms involved in the radiation response. Most of the knowledge about radiation effects concerns external beam radiation therapy (EBRT) and radiobiology has then strongly contributed to the development of this therapeutic approach. Similarly, radiobiology and dosimetry are also assumed to be ways for improving TRT, in particular in the therapy of solid tumors, which are radioresistant. However, extrapolation of EBRT radiobiology to TRT is not straightforward. Indeed, the specific physical characteristics of TRT (heterogeneous and mixed irradiation, protracted exposure, and low absorbed dose rate) differ from those of conventional EBRT (homogeneous irradiation, short exposure, and high absorbed dose rate), and consequently the response of irradiated tissues might be different. Therefore, specific TRT radiobiology needs to be explored. Determining dose–effect correlation is also a prerequisite for rigorous preclinical radiobiology studies because dosimetry provides the necessary referential to all TRT situations. It is required too for developing patient-tailored TRT in the clinic in order to estimate the best dose for tumor control, while protecting the healthy tissues, thereby improving therapeutic efficacy. Finally, it will allow to determine the relative contribution of targeted effects (assumed to be dose-related) and non-targeted effects (assumed to be non-dose-related) of ionizing radiation. However, conversely to EBRT where it is routinely used, dosimetry is still challenging in TRT. Therefore, it constitutes with radiobiology, one of the main challenges of

  9. Pancreatic ductal adenocarcinoma: From genetics to biology to radiobiology to oncoimmunology and all the way back to the clinic.

    PubMed

    Fokas, Emmanouil; O'Neill, Eric; Gordon-Weeks, Alex; Mukherjee, Somnath; McKenna, W Gillies; Muschel, Ruth J

    2015-01-01

    Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer death. Despite improvements in the clinical management, the prognosis of PDAC remains dismal. In the present comprehensive review, we will examine the knowledge of PDAC genetics and the new insights into human genome sequencing and clonal evolution. Additionally, the biology and the role of the stroma in tumour progression and response to treatment will be presented. Furthermore, we will describe the evidence on tumour chemoresistance and radioresistance and will provide an overview on the recent advances in PDAC metabolism and circulating tumour cells. Next, we will explore the characteristics and merits of the different mouse models of PDAC. The inflammatory milieu and the immunosuppressive microenvironment mediate tumour initiation and treatment failure. Hence, we will also review the inflammatory and immune escaping mechanisms and the new immunotherapies tested in PDAC. A better understanding of the different mechanisms of tumour formation and progression will help us to identify the best targets for testing in future clinical studies of PDAC. PMID:25489989

  10. Comparison of cytogenetic effects in bone marrow of mice after the flight on the biosatellite "BION-M1" and the ground-based radiobiological experiment

    NASA Astrophysics Data System (ADS)

    Dorozhkina, Olga; Vorozhtsova, Svetlana; Ivanov, Alexander

    2016-07-01

    During space flight, the astronauts are exposed to radiation exposure at low doses with low dose rates, so one of the actual areas of Radiobiology is research of action of ionizing radiation in low and ultra-low doses. Violation of the chromosome apparatus of living biosystems, ranging from viruses and bacteria to humans, is the most reliable evidence of exposure to ionizing radiation. In this regard, the study of cytogenetic damage in the cells of humans and animals is central to space radiobiology (Fedorenko B.S., 2006). In experiment "BION - M1" by anaphase method was determined level of chromosomal aberrations in bone marrow cells of tibia of mice. Flight duration biosatellite "BION - M1" (Sychev V.N. et al., 2014) was 30 days in Earth orbit. Euthanasia of experimental animals was carried out after 12 hours from the moment of landing satellite by method of cervical dislocation. The level of chromosomal aberrations in vivarium-housed control mice was 1,75 ± 0,6% and 1,8 ± 0,45%, while the mitotic index 1,46 ± 0,09% and 1,53 ± 0,05%. The content of animals in the experiment with onboard equipment led to some increase in aberrant mitosis (2,3 ± 0,4%) and reduction of the mitotic index (1,37 ± 0,02%). In the flight experiment "BION-M1" was a statistically significant increase in level of chromosome aberrations (29,7 ± 4,18%) and a decrease in the mitotic index (0,74 ± 0,07%). According to VA Shurshakova (2014), the radiation dose to mice ranged from 32 to 72 mGy and relate to a range of small doses (ICRP, 2012). In this connection we conducted a series of experiments in the ground conditions, the aim of which was the study of earliest effects of ionizing radiation in vivo in mice irradiated with low doses of γ-irradiation of 10 to 200 mGy in the first 24 hours after exposure, i.e. within the first post-radiation exposure cell cycle. Studies were carried out on adult female mice outbred ICR (CD-1) - SPF category at the age of 4-4.5 months with an average

  11. Joint bone radiobiology workshop

    SciTech Connect

    Tomich, P.A.

    1991-01-01

    The Joint Bone Radiobiology Workshop was held on July 12--13, 1991 in Toronto, Canada. This document contains the papers presented at the meeting. The five sections were: Dose-effects, Endogenous Cofactors, Tumorigenesis, New Methods and Medical Implications. The papers covered risk assessment, tissue distribution of radionuclides, lifetime studies, biological half-lifes, the influence of age at time of exposure, tumor induction by different radionuclides, microscopic localization of radionuclides, and nuclear medicine issues including tissue distribution in the skeleton and bone marrow transplantation. (MHB)

  12. CRC handbook of radiobiology

    SciTech Connect

    Prasad, K.N.

    1984-01-01

    The author presents Development of Radiobiology. A Review. Basic Cell Biology. Physics of Radiation Biology. Cellular Radiation Damage. Modifications of Cellular Radiation Damage. Repair of Radiation Damage. Molecular Radiation Biology. Radiation Syndromes and their Modifications. Radiation Damage of Skin and Mucous Membrane. Radiation Damage of Nervous Tissue. Radiation Damage of Reproductive Organs. Radiation Damage of Other Organ Systems. Radiation Immunology. Background, Medical and Commercial Sources. Radiation Injuries to Human Fetuses. Radiation-Induced Genetic Damage. Radiation Carcinogenesis: Tissue Culture Model. Radiation Carcinogenesis: Animal Model. Radiation Carcinogenesis: Human Model. Radiation Carcinogenesis: Secondary Neoplasms. After Therapy of Tumors. Other Late Effects: Aging, Cataract, Aplastic Anemia. Maximum Permissible Dose (MPD). Radiation Response of Human Tumor. Radioisotopes in Biology and Medicine.

  13. Monte Carlo role in radiobiological modelling of radiotherapy outcomes

    NASA Astrophysics Data System (ADS)

    El Naqa, Issam; Pater, Piotr; Seuntjens, Jan

    2012-06-01

    Radiobiological models are essential components of modern radiotherapy. They are increasingly applied to optimize and evaluate the quality of different treatment planning modalities. They are frequently used in designing new radiotherapy clinical trials by estimating the expected therapeutic ratio of new protocols. In radiobiology, the therapeutic ratio is estimated from the expected gain in tumour control probability (TCP) to the risk of normal tissue complication probability (NTCP). However, estimates of TCP/NTCP are currently based on the deterministic and simplistic linear-quadratic formalism with limited prediction power when applied prospectively. Given the complex and stochastic nature of the physical, chemical and biological interactions associated with spatial and temporal radiation induced effects in living tissues, it is conjectured that methods based on Monte Carlo (MC) analysis may provide better estimates of TCP/NTCP for radiotherapy treatment planning and trial design. Indeed, over the past few decades, methods based on MC have demonstrated superior performance for accurate simulation of radiation transport, tumour growth and particle track structures; however, successful application of modelling radiobiological response and outcomes in radiotherapy is still hampered with several challenges. In this review, we provide an overview of some of the main techniques used in radiobiological modelling for radiotherapy, with focus on the MC role as a promising computational vehicle. We highlight the current challenges, issues and future potentials of the MC approach towards a comprehensive systems-based framework in radiobiological modelling for radiotherapy.

  14. Radiobiological evaluation of intensity modulated radiation therapy treatments of patients with head and neck cancer: A dual-institutional study

    PubMed Central

    Narayanasamy, G.; Pyakuryal, A. P.; Pandit, S.; Vincent, J.; Lee, C.; Mavroidis, P.; Papanikolaou, N.; Kudrimoti, M.; Sio, T. T.

    2015-01-01

    In clinical practice, evaluation of clinical efficacy of treatment planning stems from the radiation oncologist's experience in accurately targeting tumors, while keeping minimal toxicity to various organs at risk (OAR) involved. A more objective, quantitative method may be raised by using radiobiological models. The purpose of this work is to evaluate the potential correlation of OAR-related toxicities to its radiobiologically estimated parameters in simultaneously integrated boost (SIB) intensity modulated radiation therapy (IMRT) plans of patients with head and neck tumors at two institutions. Lyman model for normal tissue complication probability (NTCP) and the Poisson model for tumor control probability (TCP) models were used in the Histogram Analysis in Radiation Therapy (HART) analysis. In this study, 33 patients with oropharyngeal primaries in the head and neck region were used to establish the correlation between NTCP values of (a) bilateral parotids with clinically observed rates of xerostomia, (b) esophagus with dysphagia, and (c) larynx with dysphagia. The results of the study indicated a strong correlation between the severity of xerostomia and dysphagia with Lyman NTCP of bilateral parotids and esophagus, respectively, but not with the larynx. In patients without complications, NTCP values of these organs were negligible. Using appropriate radiobiological models, the presence of a moderate to strong correlation between the severities of complications with NTCP of selected OARs suggested that the clinical outcome could be estimated prior to treatment. PMID:26500403

  15. Radiobiology of pions at LAMPF.

    PubMed

    Raju, M R; Tokita, N

    1982-12-01

    Recent radiobiology data for pion beams used in therapy are presented. The biological systems used were cultured cells suspended in gelatin and intestinal crypt assay. The importance of fast neutrons from pion stars in large treatment volumes is discussed. The data for compensating the depth dose distribution to produce uniform cell killing across the peak region are presented. The changes in biological effectiveness with peak width for pion beams (unlike heavy ions) are small because of fast neutron contribution from pion stars. The need for innovative radiobiology programs to guide high-LET radiotherapy is discussed. PMID:7161165

  16. Radiobiological research at JINR's accelerators

    NASA Astrophysics Data System (ADS)

    Krasavin, E. A.

    2016-04-01

    The half-a-century development of radiobiological studies at the Joint Institute for Nuclear Research (JINR) is reviewed on a stage-by-stage basis. With the use of the institute's accelerators, some key aspects of radiation biology have been settled, including the relative biological effectiveness (RBE) of various types of ionizing radiation with different physical characteristics; radiation-induced mutagenesis mechanisms, and the formation and repair of genetic structure damage. Practical space radiobiology problems that can be solved using high-energy charged particles are discussed.

  17. The Importance of Dosimetry Standardization in Radiobiology

    PubMed Central

    Desrosiers, Marc; DeWerd, Larry; Deye, James; Lindsay, Patricia; Murphy, Mark K; Mitch, Michael; Macchiarini, Francesca; Stojadinovic, Strahinja; Stone, Helen

    2013-01-01

    Radiation dose is central to much of radiobiological research. Precision and accuracy of dose measurements and reporting of the measurement details should be sufficient to allow the work to be interpreted and repeated and to allow valid comparisons to be made, both in the same laboratory and by other laboratories. Despite this, a careful reading of published manuscripts suggests that measurement and reporting of radiation dosimetry and setup for radiobiology research is frequently inadequate, thus undermining the reliability and reproducibility of the findings. To address these problems and propose a course of action, the National Cancer Institute (NCI), the National Institute of Allergy and Infectious Diseases (NIAID), and the National Institute of Standards and Technology (NIST) brought together representatives of the radiobiology and radiation physics communities in a workshop in September, 2011. The workshop participants arrived at a number of specific recommendations as enumerated in this paper and they expressed the desirability of creating dosimetry standard operating procedures (SOPs) for cell culture and for small and large animal experiments. It was also felt that these SOPs would be most useful if they are made widely available through mechanism(s) such as the web, where they can provide guidance to both radiobiologists and radiation physicists, be cited in publications, and be updated as the field and needs evolve. Other broad areas covered were the need for continuing education through tutorials at national conferences, and for journals to establish standards for reporting dosimetry. This workshop did not address issues of dosimetry for studies involving radiation focused at the sub-cellular level, internally-administered radionuclides, biodosimetry based on biological markers of radiation exposure, or dose reconstruction for epidemiological studies. PMID:26401441

  18. Designing a Curriculum for Clinical Experiences

    ERIC Educational Resources Information Center

    Henning, John E.; Erb, Dorothy J.; Randles, Halle Schoener; Fults, Nanette; Webb, Kathy

    2016-01-01

    The purpose of this article is to describe a collaborative effort among five teacher preparation programs to create a conceptual tool designed to put clinical experiences at the center of our programs. The authors refer to the resulting product as a clinical curriculum. The clinical curriculum describes a developmental sequence of clinical…

  19. Radiobiological influence of megavoltage electron pulses of ultra-high pulse dose rate on normal tissue cells.

    PubMed

    Laschinsky, Lydia; Karsch, Leonhard; Leßmann, Elisabeth; Oppelt, Melanie; Pawelke, Jörg; Richter, Christian; Schürer, Michael; Beyreuther, Elke

    2016-08-01

    Regarding the long-term goal to develop and establish laser-based particle accelerators for a future radiotherapeutic treatment of cancer, the radiobiological consequences of the characteristic short intense particle pulses with ultra-high peak dose rate, but low repetition rate of laser-driven beams have to be investigated. This work presents in vitro experiments performed at the radiation source ELBE (Electron Linac for beams with high Brilliance and low Emittance). This accelerator delivered 20-MeV electron pulses with ultra-high pulse dose rate of 10(10) Gy/min either at the low pulse frequency analogue to previous cell experiments with laser-driven electrons or at high frequency for minimizing the prolonged dose delivery and to perform comparison irradiation with a quasi-continuous electron beam analogue to a clinically used linear accelerator. The influence of the different electron beam pulse structures on the radiobiological response of the normal tissue cell line 184A1 and two primary fibroblasts was investigated regarding clonogenic survival and the number of DNA double-strand breaks that remain 24 h after irradiation. Thereby, no considerable differences in radiation response were revealed both for biological endpoints and for all probed cell cultures. These results provide evidence that the radiobiological effectiveness of the pulsed electron beams is not affected by the ultra-high pulse dose rates alone. PMID:27193178

  20. Design study of the ESS-Bilbao 50 MeV proton beam line for radiobiological studies

    NASA Astrophysics Data System (ADS)

    Huerta-Parajon, M.; Martinez-Ballarin, R.; Abad, E.

    2015-02-01

    The ESS-Bilbao proton accelerator facility has been designed fulfilling the European Spallation Source (ESS) specifications to serve as the Spanish contribution to the ESS construction. Furthermore, several applications of the ESS-Bilbao proton beam are being considered in order to contribute to the knowledge in the field of radiobiology, materials and aerospace components. Understanding of the interaction of radiation with biological systems is of vital importance as it affects important applications such as cancer treatment with ion beam therapy among others. ESS-Bilbao plans to house a facility exclusively dedicated to radiobiological experiments with protons up to 50 MeV. Beam line design, optimisation and initial calculations of flux densities and absorbed doses were undertaken using the Monte Carlo simulation package FLUKA. A proton beam with a flux density of about 106 protons/cm2 s reaches the water sample with a flat lateral distribution of the dose. The absorbed dose at the pristine Bragg peak calculated with FLUKA is 2.4 ± 0.1 Gy in 1 min of irradiation time. This value agrees with the clinically meaningful dose rates, i.e. around 2 Gy/min, used in hadrontherapy. Optimisation and validation studies in the ESS-Bilbao line for radiobiological experiments are detailed in this article.

  1. Dosimetry and radiobiological studies of automated alpha-particle irradiator.

    PubMed

    M V, Jyothish Babu; Shinde, Sanjay G; S, Sunil Kumar; Ali, Manjoor; Vasumathy, R; Kumar, Amit; Kolekar, R; Kumar, Manish; Nema, P; Bhagwat, P V; Pandey, Badri N

    2013-01-01

    Understanding the effect of alpha radiation on biological systems is an important component of radiation risk assessment and associated health consequences. However, due to the short path length of alpha radiation in the atmosphere, in vitro radiobiological experiments cannot be performed with accuracy in terms of dose and specified exposure time. The present paper describes the design and dosimetry of an automated alpha-particle irradiator named 'BARC BioAlpha', which is suitable for in vitro radiobiological studies. Compared to alpha irradiators developed in other laboratories, BARC BioAlpha has integrated computer-controlled movement of the alpha-particle source, collimator, and electronic shutter. The diaphragm blades of the electronic shutter can control the area (diameter) of irradiation without any additional shielding, which is suitable for radiobiological bystander studies. To avoid irradiation with incorrect parameters, a software interlock is provided to prevent shutter opening, unless the user-specified speed of the source and collimator are achieved. The dosimetry of the alpha irradiator using CR-39 and silicon surface barrier detectors showed that ~4 MeV energy of the alpha particle reached the cells on the irradiation dish. The alpha irradiation was also demonstrated by the evaluation of DNA double-strand breaks in human cells. In conclusion, 'BARC BioAlpha' provides a user-friendly alpha irradiation system for radiobiological experiments with a novel automation mechanism for better accuracy of dose and exposure time. PMID:24266413

  2. Vardenafil: update on clinical experience.

    PubMed

    Pryor, J

    2002-02-01

    Vardenafil, a potent and selective phosphodiesterase 5 inhibitor, has entered phase 3 clinical trials. Pharmacodynamic studies showed that the maximum plasma concentration after oral administration of 20-40 mg of vardenafil occurred in 0.7-0.9 h, the half-life was 4-5 h, and negligible amounts remained in the circulation after 24 h. The efficacy of vardenafil compared with placebo was shown in RigiScan studies, a phase 2 study involving 601 men with mild-to-severe erectile dysfunction for at least 6 months, and a phase 3 study involving 452 diabetic men. Adverse effects were not severe and tended to decrease with time. PMID:11850738

  3. Clinical experience with CT colonography

    NASA Astrophysics Data System (ADS)

    Reed, Judd E.; Garry, John L.; Wilson, Lynn A.; Johnson, C. Daniel

    2000-04-01

    Since the introduction of Computed Tomographic Colonography (CTC) in 1995, many advances in computer equipment and software have become available. Despite these advances, the promise of colon cancer prevention has not been realized. A colorectal screening tool that performs at a high level, is acceptable to patients, and can be performed safely and at low cost holds promise of saving lives in the future. Our institution has performed over two hundred seventy five clinical CTC examinations. These scans, which each entail a supine and a prone acquisition, only differ from our research protocol in the necessity of an expeditious interpretation. Patients arrive for their CTC examination early in the morning following a period of fasting and bowel preparation. If a CTC examination has a positive finding, the patient is scheduled for colonoscopic polypectomy that same morning. To facilitate this, the patients are required to continue fasting until the CTC examination has been interpreted. It is therefore necessary to process the CTC examination very quickly to minimize patient discomfort. A positive CTC result occurred in fifteen percent of examinations. Among these positive results, the specificity has been in excess of ninety five percent. Additionally, life threatening extra-colonic lesions were discovered in two percent of the screened population.

  4. New clinical experience with tramadol.

    PubMed

    Sunshine, A

    1994-01-01

    The analgesic efficacy of tramadol has been recently reassessed as part of a new clinical development programme to support an application for registration in the USA. This article reviews the results of single dose and short term studies of oral tramadol 50, 75, 100 and 150 mg in various acute pain conditions. In a double-blind single dose study conducted in 161 patients with severe pain following caesarean section, tramadol 75 and 150 mg and the combination of paracetamol 650 mg with dextropropoxyphene napsylate 100 mg were shown to be effective and statistically superior to placebo. The results from this and 17 other similar studies in patients with pain after surgery (n = 1594) or dental extraction (n = 1859) including other comparators were included in a pooled analysis. Tramadol 100 mg was the optimal single dose for acute pain and tramadol 50 mg showed similar analgesic efficacy to codeine 60 mg. Multiple dose short term studies (n = 520) with tramadol 50, 75 and 100 mg demonstrated a statistically significant and dose-dependent reduction in the consumption of either ibuprofen or morphine as escape medication. New pharmacokinetic data show that steady-state plasma tramadol concentrations reached after oral administration of 50 mg doses every 6 hours are similar to those obtained after administration of a 100 mg single oral dose (250 micrograms/L). This rationale is supported by the results of long term studies in which the average daily dose of tramadol was approximately 250 mg. PMID:7517826

  5. Clinical experience with nuclear pacemakers.

    PubMed

    Parsonnet, V; Myers, G H; Gilbert, L; Zucker, I R

    1975-12-01

    Approximately 1,400 nuclear pacemakers have been implanted in patients since April, 1970, without a single battery failure; 64 of these have been implanted at the Newark Beth Israel Medical Center. All except four of the 64 pulse generators were attached to transvenous electrodes, 39 to pacing wires already in place. Fifty-nine of the 64 units are in service and continue to function normally in a follow-up period of up to 2 years. In the total worldwide experience, 70 pacemakers are out of service, approximately half because of the patient's death, and the rest for infection or lead problems, and only three or four because of difficulties with components. The first 15 ARCO pacemakers implanted 2 years ago continue to function well. Of the 15 control pacemakers implanted at the same time, one unit has failed. We have concluded that a nuclear pacemaker should not be used in a patient with limited life expectancy or in an infant, but for the otherwise healthy young or middle-age individual, it should be the unit of choice. PMID:1188620

  6. Radiobiology of tissue reactions.

    PubMed

    Dörr, W

    2015-06-01

    Tissue effects of radiation exposure are observed in virtually all normal tissues, with interactions when several organs are involved. Early reactions occur in turnover tissues, where proliferative impairment results in hypoplasia; late reactions, based on combined parenchymal, vascular, and connective tissue changes, result in loss of function within the exposed volume; consequential late effects develop through interactions between early and late effects in the same organ; and very late effects are dominated by vascular sequelae. Invariably, involvement of the immune system is observed. Importantly, latent times of late effects are inversely dependent on the biologically equieffective dose. Each tissue component and--importantly--each individual symptom/endpoint displays a specific dose-effect relationship. Equieffective doses are modulated by exposure conditions: in particular, dose-rate reduction--down to chronic levels--and dose fractionation impact on late responding tissues, while overall exposure time predominantly affects early (and consequential late) reactions. Consequences of partial organ exposure are related to tissue architecture. In 'tubular' organs (gastrointestinal tract, but also vasculature), punctual exposure affects function in downstream compartments. In 'parallel' organs, such as liver or lungs, only exposure of a significant (organ-dependent) fraction of the total volume results in clinical consequences. Forthcoming studies must address biomarkers of the individual risk for tissue reactions, and strategies to prevent/mitigate tissue effects after exposure. PMID:25816259

  7. Fundamental space radiobiology

    NASA Technical Reports Server (NTRS)

    Nelson, Gregory A.

    2003-01-01

    The unique feature of the space radiation environment is the dominance of high-energy charged particles (HZE or high LET radiation) emitted by the Sun and galactic sources, or trapped in the Van Allen radiation belts. These charged particles present a significant hazard to space flight crews, and accelerator-based experiments are underway to quantify the health risks due to unavoidable radiation exposure. There are three principal properties of charged particles that distinguish them from conventional radiation, i.e. gamma rays and x-rays. First, they have a defined range in matter rather than an exponential absorption profile. Second, they undergo nuclear reactions to produce secondary particles. Third, and most important, they deposit their energy along well-defined linear paths or tracks rather than diffuse fields. The structured energy deposition pattern interacts on multiple scales with the biological structures of DNA, cells and tissues to produce correlated patterns of damage that evade repair systems. Traditional concepts of dose and its associated normalization parameter, RBE (relative biological effectiveness), break down under experimental scrutiny, and probabilistic models of risk based on the number of particle traversals per cell may be more appropriate. Unique patterns of DNA damage, gene expression, mobilization of repair proteins, activation of cytokines and remodeling of cellular microenvironment are observed following exposure to high LET radiation. At low levels of exposure the communication of bioactive substances from irradiated to unirradiated "bystander" cells can amplify the damage and cause a significant deviation from linearity in dose vs. response relations. Under some circumstances, there is even a multigenerational delay in the expression of radiation-induced genetic damage (genomic instability) which is not strictly dose dependent. These issues and the experimental evidence derived from ground based experiments at particle

  8. Canadian experience with structured clinical examinations.

    PubMed Central

    Grand'Maison, P; Lescop, J; Brailovsky, C A

    1993-01-01

    The use of structured clinical examinations to improve the evaluation of medical students and graduates has become significantly more common in the past 25 years. Many Canadian medical educators have contributed to the development of this technique. The Canadian experience is reviewed from the introduction of simulated-standardized patients and objective-structured clinical examinations to more recent developments and the use of such examinations for licensure and certification. PMID:8477384

  9. Target fragmentation in radiobiology

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Cucinotta, Francis A.; Shinn, Judy L.; Townsend, Lawrence W.

    1993-01-01

    Nuclear reactions in biological systems produce low-energy fragments of the target nuclei seen as local high events of linear energy transfer (LET). A nuclear-reaction formalism is used to evaluate the nuclear-induced fields within biosystems and their effects within several biological models. On the basis of direct ionization interaction, one anticipates high-energy protons to have a quality factor and relative biological effectiveness (RBE) of unity. Target fragmentation contributions raise the effective quality factor of 10 GeV protons to 3.3 in reasonable agreement with RBE values for induced micronuclei in bean sprouts. Application of the Katz model indicates that the relative increase in RBE with decreasing exposure observed in cell survival experiments with 160 MeV protons is related solely to target fragmentation events. Target fragment contributions to lens opacity given an RBE of 1.4 for 2 GeV protons in agreement with the work of Lett and Cox. Predictions are made for the effective RBE for Harderian gland tumors induced by high-energy protons. An exposure model for lifetime cancer risk is derived from NCRP 98 risk tables, and protraction effects are examined for proton and helium ion exposures. The implications of dose rate enhancement effects on space radiation protection are considered.

  10. PACS clinical experience at Georgetown University.

    PubMed

    Horii, S C; Mun, S K; Levine, B; Lo, B; Garra, B S; Zeman, R K; Freedman, M; Leftridge, C; Schellinger, D; Keyes, J

    1991-01-01

    Georgetown University Hospital has been operating an image management and communications system (IMACS or PACS) for three-and-a-half years. This work was initially funded under the Army Medical Research and Development Command Digital Imaging Network Systems (DINS) project. The system was taken from a research system supporting only radiology tasks to one extended to clinical use, and has been used in clinical work for two-and-a-half years. This paper will summarize our PACS clinical experience and will describe the operational features implemented and those still necessary. PMID:1913567

  11. Early experiences of accredited clinical informatics fellowships.

    PubMed

    Longhurst, Christopher A; Pageler, Natalie M; Palma, Jonathan P; Finnell, John T; Levy, Bruce P; Yackel, Thomas R; Mohan, Vishnu; Hersh, William R

    2016-07-01

    Since the launch of the clinical informatics subspecialty for physicians in 2013, over 1100 physicians have used the practice and education pathways to become board-certified in clinical informatics. Starting in 2018, only physicians who have completed a 2-year clinical informatics fellowship program accredited by the Accreditation Council on Graduate Medical Education will be eligible to take the board exam. The purpose of this viewpoint piece is to describe the collective experience of the first four programs accredited by the Accreditation Council on Graduate Medical Education and to share lessons learned in developing new fellowship programs in this novel medical subspecialty. PMID:27206458

  12. Toolkit for determination of dose-response relations, validation of radiobiological parameters and treatment plan optimization based on radiobiological measures.

    PubMed

    Mavroidis, Panayiotis; Tzikas, Athanasios; Papanikolaou, Nikos; Lind, Bengt K

    2010-10-01

    Accurately determined dose-response relations of the different tumors and normal tissues should be estimated and used in the clinic. The aim of this study is to demonstrate developed tools that are necessary for determining the dose-response parameters of tumors and normal tissues, for clinically verifying already published parameter sets using local patient materials and for making use of all this information in the optimization and comparison of different treatment plans and radiation techniques. One of the software modules (the Parameter Determination Module) is designed to determine the dose-response parameters of tumors and normal tissues. This is accomplished by performing a maximum likelihood fitting to calculate the best estimates and confidence intervals of the parameters used by different radiobiological models. Another module of this software (the Parameter Validation Module) concerns the validation and compatibility of external or reported dose-response parameters describing tumor control and normal tissue complications. This is accomplished by associating the expected response rates, which are calculated using different models and published parameter sets, with the clinical follow-up records of the local patient population. Finally, the last module of the software (the Radiobiological Plan Evaluation Module) is used for estimating and optimizing the effectiveness a treatment plan in terms of complication-free tumor control, P(+). The use of the Parameter Determination Module is demonstrated by deriving the dose-response relation of proximal esophagus from head and neck cancer radiotherapy. The application of the Parameter Validation Module is illustrated by verifying the clinical compatibility of those dose-response parameters with the examined treatment methodologies. The Radiobiological Plan Evaluation Module is demonstrated by evaluating and optimizing the effectiveness of head and neck cancer treatment plans. The results of the radiobiological

  13. Radioembolization of Hepatic Lesions from a Radiobiology and Dosimetric Perspective

    PubMed Central

    Cremonesi, Marta; Chiesa, Carlo; Strigari, Lidia; Ferrari, Mahila; Botta, Francesca; Guerriero, Francesco; De Cicco, Concetta; Bonomo, Guido; Orsi, Franco; Bodei, Lisa; Di Dia, Amalia; Grana, Chiara Maria; Orecchia, Roberto

    2014-01-01

    Radioembolization (RE) of liver cancer with 90Y-microspheres has been applied in the last two decades with notable responses and acceptable toxicity. Two types of microspheres are available, glass and resin, the main difference being the activity/sphere. Generally, administered activities are established by empirical methods and differ for the two types. Treatment planning based on dosimetry is a prerogative of few centers, but has notably gained interest, with evidence of predictive power of dosimetry on toxicity, lesion response, and overall survival (OS). Radiobiological correlations between absorbed doses and toxicity to organs at risk, and tumor response, have been obtained in many clinical studies. Dosimetry methods have evolved from the macroscopic approach at the organ level to voxel analysis, providing absorbed dose spatial distributions and dose–volume histograms (DVH). The well-known effects of the external beam radiation therapy (EBRT), such as the volume effect, underlying disease influence, cumulative damage in parallel organs, and different tolerability of re-treatment, have been observed also in RE, identifying in EBRT a foremost reference to compare with. The radiobiological models – normal tissue complication probability and tumor control probability – and/or the style (DVH concepts) used in EBRT are introduced in RE. Moreover, attention has been paid to the intrinsic different activity distribution of resin and glass spheres at the microscopic scale, with dosimetric and radiobiological consequences. Dedicated studies and mathematical models have developed this issue and explain some clinical evidences, e.g., the shift of dose to higher toxicity thresholds using glass as compared to resin spheres. This paper offers a comprehensive review of the literature incident to dosimetry and radiobiological issues in RE, with the aim to summarize the results and to identify the most useful methods and information that should accompany future studies

  14. First time rounding experiences for nonclinicians: the Cleveland Clinic experience.

    PubMed

    Greenwald, Laura R; Nowacki, Amy S; Stoller, James K

    2015-01-01

    Clinical rounds serve several key objectives in academic medical centers: providing a forum for patient communication, clinical decision making, and teaching. Nonclinical colleagues ordinarily do not have the opportunity to round, and the idea of implementing a rounding program that includes nonclinical colleagues has received little attention to date. Reasoning that a rounding program with nonclinicians could enhance (1) understanding of the organization's clinical mission, (2) appreciation of caregivers' roles, and (3) engagement, the authors created such a program. From 2010 to 2013, 51 nonclinicians within the Cleveland Clinic Education Institute participated; 14 submitted written reflections, and 27 responded to a survey about their experience. Overall, 12 themes emerged that suggest an enhanced familiarity with the institution and increased engagement and alignment with its mission. Notably, the results align with a long-standing focus on organizational engagement and an observed increase in mean engagement scores since the program was implemented. PMID:24519444

  15. Novel Radiobiological Gamma Index for Evaluation of 3-Dimensional Predicted Dose Distribution

    SciTech Connect

    Sumida, Iori; Yamaguchi, Hajime; Kizaki, Hisao; Aboshi, Keiko; Tsujii, Mari; Yoshikawa, Nobuhiko; Yamada, Yuji; Suzuki, Osamu; Seo, Yuji; Isohashi, Fumiaki; Yoshioka, Yasuo; Ogawa, Kazuhiko

    2015-07-15

    Purpose: To propose a gamma index-based dose evaluation index that integrates the radiobiological parameters of tumor control (TCP) and normal tissue complication probabilities (NTCP). Methods and Materials: Fifteen prostate and head and neck (H&N) cancer patients received intensity modulated radiation therapy. Before treatment, patient-specific quality assurance was conducted via beam-by-beam analysis, and beam-specific dose error distributions were generated. The predicted 3-dimensional (3D) dose distribution was calculated by back-projection of relative dose error distribution per beam. A 3D gamma analysis of different organs (prostate: clinical [CTV] and planned target volumes [PTV], rectum, bladder, femoral heads; H&N: gross tumor volume [GTV], CTV, spinal cord, brain stem, both parotids) was performed using predicted and planned dose distributions under 2%/2 mm tolerance and physical gamma passing rate was calculated. TCP and NTCP values were calculated for voxels with physical gamma indices (PGI) >1. We propose a new radiobiological gamma index (RGI) to quantify the radiobiological effects of TCP and NTCP and calculate radiobiological gamma passing rates. Results: The mean RGI gamma passing rates for prostate cases were significantly different compared with those of PGI (P<.03–.001). The mean RGI gamma passing rates for H&N cases (except for GTV) were significantly different compared with those of PGI (P<.001). Differences in gamma passing rates between PGI and RGI were due to dose differences between the planned and predicted dose distributions. Radiobiological gamma distribution was visualized to identify areas where the dose was radiobiologically important. Conclusions: RGI was proposed to integrate radiobiological effects into PGI. This index would assist physicians and medical physicists not only in physical evaluations of treatment delivery accuracy, but also in clinical evaluations of predicted dose distribution.

  16. Nurses’ experiences of humour in clinical settings

    PubMed Central

    Ghaffari, Fatemeh; Dehghan-Nayeri, Nahid; Shali, Mahboubeh

    2015-01-01

    Background: Providing holistic nursing care when there is a shortage of personnel and equipment exposes nurses to stress and a higher risk of occupational burnout. Humour can promote nurses’ health and influence nursing care. The aim of this study was to describe nurses’ experiences of humour in clinical settings and factors affecting it. Methods: This qualitative study investigated nurses’ experiences of humour. Five hospitals affiliated to Tehran University of Medical Sciences provided the setting for this study. The participants comprised of 17 nurses with master’s and Baccalaureate degrees (BSN) in nursing. These nurses worked at educational hospitals affiliated to Tehran University of Medical Sciences and had minimum work experience of 12 months in various clinical wards. Nurses from all wards were invited to participate in this study. The data were collected through semi structure interviews using guides comprising probing questions. Telephonic interviews were used to further supplement the data. The data were analysed using conventional content analysis. Results: The data were classified into five themes including the dynamics of humour, condition enforcement, Risk making probability, Instrumental use and Change: opportunities and threats. Conclusion: Understanding nurses’ perceptions and experiences of humour helps identify its contributing factors and provides valuable guidelines for enhancing nurses and patients’ mental, emotional and physical health. Spreading a culture of humour through teaching methods can improve workplace cheerfulness and highlights the importance of humour in patient care in nurses and nursing students. PMID:26034735

  17. Nursing students' perceptions of clinical experience.

    PubMed

    Windsor, A

    1987-04-01

    Senior nursing students were interviewed in this study to better understand the clinical learning experience from the students' point of view. Results of the study revealed that the nursing students were indeed learning in their clinical experience. The major categories of learning were classified as nursing skills, time management, and professional socialization. The quality of learning was reportedly affected by the quality of the student's preparation, characteristics of the instructor, and the variety of clinical opportunities to which students were exposed. The data also reflected a pattern of student development which was separated into three stages. The first stage was permeated with anxiety and obsession with the rules of task performance. The second stage was a difficult transition period where students struggled with identifying the roles of nurses. During the final stage, the students become more comfortable with performing nursing tasks and become interested in expanding their role and becoming more independent. As the students strived for independence, they identified more closely with staff nurses and withdrew from instructors. PMID:3035128

  18. Radiobiological considerations in magna-field irradiation

    SciTech Connect

    Evans, R.G.

    1983-12-01

    Radiobiological considerations are described for total body irradiation (TBI) as given to patients undergoing bone marrow transplantation (BMT). Although much progress has been made in the use of BMT for refractory leukemias, many patients still die from interstitial pneumonia and relapse. Fractionated TBI has been introduced in order to improve leukemic cell kill, while increasing the degree of normal tissue tolerance. Traditionally, bone marrow stem cells, leukemic cells and immunocytes have been considered as having a limited ability to repair radiation damage while cells of lung tissue and intestinal epithelial cells have a greater capacity. During fractionated radiation therapy or continuous low-dose rate exposure, repair of sublethal damage between fractions allows greater recovery in the cells of lung tissue to those in the bone marrow. Clinically, the potential benefit of six fractions over one fraction or low dose-rate TBI has yet to be proved, although there is suggestive evidence for a reduced incidence of interstitial pneumonitis. However, other extraneous factors such as doses to the lung, differences in conditioning regimens, effect of increased delay in BMT for patients receiving fractionated TBI, and the unmeasurable differences between institutions make definite conclusions impossible. Despite this, a consensus for dose fractionation has developed and most centers are moving away from the use of large single dose TBI.

  19. Preliminary clinical experience in cardiology with sonazoid.

    PubMed

    Marelli, C

    2000-08-17

    Sonazoid (formerly NC100100) is a new ultrasound contrast agent for intravenous injection developed by Nycomed-Amersham. It consists of perfluorocarbon microbubbles that are stabilized with a surfactant and are within a well-defined size range (median diameter approximately 3 microm). Due to the low diffusibility and blood solubility of the gas, the controlled size distribution of the microbubbles, and the flexibility of the shell, Sonazoid is a free-flowing tracer capable of crossing the pulmonary capillary bed after peripheral intravenous injection. It is stable enough for the duration of the ultrasound examination and provides echo enhancement useful for clinical requirements. The preliminary clinical experience in cardiology indications, including its use in reducing the frequency of inadequate echocardiographic studies in patients with suboptimal echocardiograms, and its use as a myocardial perfusion agent in the setting of acute myocardial ischemia is briefly discussed. PMID:10997345

  20. [Clinical-parasitological experiences in Cameroon].

    PubMed

    Schubert, S

    1991-02-01

    Clinical-parasitological experiences collected 1989 in Cameroon during a 6-weeks lasting medical work are reported. Malaria tropica is by far the greatest problem due to the impossibility of an effective epidemiologic control, further to rising drug resistances. Beside malaria there are plenty of other parasitoses, but they are more restricted to lower social groups and to certain geographic regions--to the extreme Northern part of Cameroon in particular. Furthermore the actual situation depends also from epidemiologic control programmes. So the trypanosomiasis seems to be under epidemiologic control, the onchocerciasis in opposite to it has been increased again due to the absence of an effective control programme at present. PMID:2039090

  1. Percutaneous endoscopic lumbar discectomy - early clinical experience.

    PubMed

    Hirano, Yoshitaka; Mizuno, Junichi; Takeda, Masaaki; Itoh, Yasunobu; Matsuoka, Hidenori; Watanabe, Kazuo

    2012-01-01

    We report our early clinical experience with percutaneous endoscopic lumbar discectomy (PELD) for herniated nucleus pulposus (HNP) in the lumbar spine. We introduced PELD to our clinical practice in June 2009. A total of 311 patients with degenerative lumbar spine disease were treated in our hospital up to August 2011. Thirty-seven patients with lumbar HNP were treated by PELD. PELD was carried out under local anesthesia, and the endoscope was continuously irrigated with saline. Twenty-eight patients were treated through the transforaminal approach, 5 were treated through the interlaminar approach, and 4 were treated through the extraforaminal approach. Surgery was discontinued due to uncontrollable intraoperative pain or anatomical inaccessibility in one case of the interlaminar approach and 2 cases of the extraforaminal approach. In the other 34 patients, the elapsed time of surgery was 34 to 103 minutes (mean 62.4 minutes). Extracorporeal blood loss was insignificant. Immediate symptom relief was achieved in all patients, and postoperative magnetic resonance imaging revealed sufficient removal of the HNP. The length of the postoperative hospital stay was 1 or 2 days in all patients. The surgical method of PELD is completely different from percutaneous nucleotomy, and the aim is to directly remove the HNP with minimum damage to the musculoskeletal structure. Although this study is based on our early clinical outcomes, PELD seemed to be a promising minimally invasive surgery for HNP in the lumbar spine. PMID:23006872

  2. Relevance of radiobiological concepts in radionuclide therapy of cancer.

    PubMed

    Kumar, Chandan; Shetake, Neena; Desai, Sejal; Kumar, Amit; Samuel, Grace; Pandey, Badri N

    2016-04-01

    Purpose Radionuclide therapy (RNT) is a rapidly growing area of clinical nuclear medicine, wherein radionuclides are employed to deliver cytotoxic dose of radiation to the diseased cells/tissues. During RNT, radionuclides are either directly administered or delivered through biomolecules targeting the diseased site. RNT has been clinically used for diverse range of diseases including cancer, which is the focus of the review. Conclusions The major emphasis in RNT has so far been given towards developing peptides/antibodies and other molecules to conjugate a variety of therapeutic radioisotopes for improved targeting/delivery of radiation dose to the tumor cells. Despite that, many of the RNT approaches have not achieved their desired therapeutic success probably due to poor knowledge about complex and dynamic (i) fate of radiolabeled molecules; (ii) radiation dose delivered; (iii) cellular heterogeneity in tumor mass; and (iv) cellular radiobiological response. Based on understanding gathered during recent years, it may be stated that besides the absorbed dose, the net radiobiological response of tumor/normal cells also determines the clinical response of radiotherapeutic modalities including RNT. The radiosensitivity of tumor/normal cells is governed by radiobiological phenomenon such as radiation-induced bystander effect, genomic instability, adaptive response and low dose hyper-radiosensitivity. These concepts have been well investigated in the context of external beam radiotherapy, but their clinical implications during RNT have received meagre attention. In this direction, a few studies performed using in vitro and in vivo models envisage the possibilities of exploiting the radiobiological knowledge for improved therapeutic outcome of RNT. Abbreviations ALL Acute Lymphoid Leukaemia AML Acute Myeloid Leukaemia CEA Carcinoembryonic Antigen CD Cluster of Differentiation CLL Chronic Lymphocytic Leukaemia CNS Central Nervous System CPP Cell Penetrating Peptide, DC

  3. A Curriculum Model for an Integrated Senior Year Clinical Experience.

    ERIC Educational Resources Information Center

    Wukasch, Ruth N.; Blue, Carolyn L.; Overbay, Jane

    2000-01-01

    A flexible clinical experience for nursing seniors integrates pediatrics, public health, and nursing leadership. Experiences in hospital units, schools, nurse-directed clinics, and home visits expose students to a wide range of settings and issues. (SK)

  4. Radiobiological compensation: A case study of uterine cervix cancer with concurrent chemotherapy

    SciTech Connect

    Herrera, Higmar; Yanez, Elvia; Lopez, Jesus

    2012-10-23

    The case of a patient diagnosed with uterine cervix cancer is presented as an example of the clinical application of the radiobiological compensation method implemented at Centro Estatal de Cancerologia de Durango. Radiotherapy treatment was initially modified to compensate for the chemotherapy component and, as medical complications arose during treatment delivery resulting in an 18 days gap, new compensation followed. All physical and radiobiological assumptions to calculate the Biologically Effective Dose in the external beam and brachytherapy parts of the treatment are presented. Good local control of the tumor was achieved, the theoretical tolerance limits for the organs at risk were not surpassed and the patient manifested no extensive morbidity.

  5. Radiobiological compensation: A case study of uterine cervix cancer with concurrent chemotherapy

    NASA Astrophysics Data System (ADS)

    Herrera, Higmar; Yañez, Elvia; López, Jesús

    2012-10-01

    The case of a patient diagnosed with uterine cervix cancer is presented as an example of the clinical application of the radiobiological compensation method implemented at Centro Estatal de Cancerología de Durango. Radiotherapy treatment was initially modified to compensate for the chemotherapy component and, as medical complications arose during treatment delivery resulting in an 18 days gap, new compensation followed. All physical and radiobiological assumptions to calculate the Biologically Effective Dose in the external beam and brachytherapy parts of the treatment are presented. Good local control of the tumor was achieved, the theoretical tolerance limits for the organs at risk were not surpassed and the patient manifested no extensive morbidity.

  6. National Radiobiology Archives distributed access programmer's guide

    SciTech Connect

    Prather, J. C.; Smith, S. K.; Watson, C. R.

    1991-12-01

    The National Radiobiology Archives is a comprehensive effort to gather, organize, and catalog original data, representative specimens, and supporting materials related to significant radiobiology studies. This provides researchers with information for analyses which compare or combine results of these and other studies and with materials for analysis by advanced molecular biology techniques. This Programmer's Guide document describes the database access software, NRADEMO, and the subset loading script NRADEMO/MAINT/MAINTAIN, which comprise the National Laboratory Archives Distributed Access Package. The guide is intended for use by an experienced database management specialist. It contains information about the physical and logical organization of the software and data files. It also contains printouts of all the scripts and associated batch processing files. It is part of a suite of documents published by the National Radiobiology Archives.

  7. Johnson Space Center Flight Medicine Clinic Experience

    NASA Technical Reports Server (NTRS)

    Landry, Trela

    2006-01-01

    Being a member of the Flight Medicine Clinic (FMC) Staff is a great experience. I joined the FMC staff 2 years ago when I became part of the Kelsey-Seybold team. The FMC staff consists of Flight Surgeons, Family Clinic Physician, Nursing staff, Wellness Coordinator and Support staff. We serve as the Primary Care Physicians for the astronauts and their families and provide annual physicals for the retired astronauts. We have approximately 800 patients in the FMC. As the Family Clinic Physician, I care for the astronaut spouses and children and provide annual physicals for the retired astronauts. Since we have a small patient population, we have the opportunity to spend increased personal time with our patients, which I enjoy. We have a pretty healthy patient population, who are very interested in their overall health and preventive care. In preparation for a shuttle launch, our nursing staff assists the flight surgeons with the astronaut physical exams, which occur 10 days prior to launch and again 3 days after their return. We also provide Primary Contact physicals for the families and guests, who will be in close contact with shuttle crew members. During these physicals, we provide education, emphasizing the importance of preventing the spread of communicable diseases to shuttle crew members. Being a part of the Space Medicine Program is an honor. To know that you contribute in some way to our nation s Space Program is very special. (This article was prepared by Dr. Trela Landry, M.D. for inclusion in a Kelsey-Seybold newsletter on 25 OCT 2006.)

  8. Application of SSNTDs in radiobiological investigations aboard recoverable satellites.

    PubMed

    Huang, R Q; Gu, R Q; Li, Q

    1997-01-01

    In recent years some Biostack experiments including a wide spectrum of biological objects have been devoted to study of the radiobiological effects on dry seeds aboard recoverable satellites. Some impressive phenomena have been observed. Clearly, the large amount of energy deposited by the highly ionizing heavy nuclei of cosmic rays is the principal reason for the induced aberrations of the chromosomes of wheat root tip cells. A methodical description of the experimental arrangement and procedure of handling and evaluation of given. The preliminary physical and biological results from the experimental "wheat seeds" are presented. PMID:11541794

  9. Transhiatal Esophagectomy: Clinical Experience and Refinements

    PubMed Central

    Orringer, Mark B.; Marshall, Becky; Iannettoni, Mark D.

    1999-01-01

    Objective To review the authors’ clinical experience with transhiatal esophagectomy (THE) and the refinements in this procedure that have evolved. Background Increased use of THE during the past two decades has generated controversy about the merits and safety of this approach compared with transthoracic esophageal resection. The authors’ large THE experience provides a valuable basis for benchmarking data regarding the procedure. Methods The results of THE were analyzed retrospectively using the authors’ prospectively established esophageal resection database and follow-up information on these patients. Results From 1976 to 1998, THE was performed in 1085 patients, 26% with benign disease and 74% with cancer. The procedure was possible in 98.6% of cases. Stomach was the esophageal substitute in 96%. The hospital mortality rate was 4%. Blood loss averaged 689 cc. Major complications were anastomotic leak (13%), atelectasis/pneumonia (2%), intrathoracic hemorrhage, recurrent laryngeal nerve paralysis, chylothorax, and tracheal laceration (<1% each). Actuarial survival of patients with carcinoma equaled or exceeded that reported after transthoracic esophagectomy. Late functional results were good or excellent in 70%. With preoperative pulmonary and physical conditioning, a side-to-side stapled cervical esophagogastric anastomosis (<3% incidence of leak), and postoperative epidural anesthesia, the need for an intensive care unit stay has been eliminated and the length of stay reduced to 7 days. Conclusion THE is possible in most patients requiring esophageal resection and can be performed with greater safety and fewer complications than the traditional transthoracic approaches. PMID:10493486

  10. Nurses' experiences of clinical commissioning group boards.

    PubMed

    Allan, Helen; O'Driscoll, Mike; Savage, Jan; Lee, Gay; Dixon, Roz

    2016-06-15

    Aim To explore the experience of governing body nurses appointed to clinical commissioning group (CCG) boards; how they perform their responsibilities; and their perceived effectiveness in ensuring safe, patient-centred care and the factors that influence their effectiveness. Method This was a small pilot study using a mixed methods approach. There were four phases of the study: literature review, qualitative data collection (interviews), quantitative data collection (survey), and final data analysis. Findings In the early stages of the formation of CCGs, few governing body nurses had relevant experience to meet the needs of a strategic role, and many of these nurses had no proper job description, too little time to carry out their responsibilities, little management support, and unequal access to training, development, formal support or supervision compared to GP colleagues. Two working patterns or models of work of governing body nurses emerged: the full-time integrated executive statutory role and the part-time non-executive statutory role. Quality and quality assurance were the most frequently cited roles or responsibilities of governing body nurses in CCGs, and their highest priority was to improve the population's health. Conclusion The role of governing body nurse has emerged at a time of organisational change, and following extensive criticism of nursing and nurses in the media. Nurses' roles and experiences are affected by these contextual events and by the emerging structures and diversity of CCGs. Further research is required into the leadership role of governing body nurses, succession planning, and the effectiveness of their relationships with other senior nurses. PMID:27305258

  11. National Radiobiology Archives Distributed Access user's manual

    SciTech Connect

    Watson, C.; Smith, S. ); Prather, J. )

    1991-11-01

    This User's Manual describes installation and use of the National Radiobiology Archives (NRA) Distributed Access package. The package consists of a distributed subset of information representative of the NRA databases and database access software which provide an introduction to the scope and style of the NRA Information Systems.

  12. [Aerospace radiobiology: 35 years (1960-1995)].

    PubMed

    Ushakov, I B; Davydov, B I

    1996-01-01

    The paper gives a brief history of the birth and development of aerospace radiobiology at the Institute of Aviation and Space Medicine. It covers from the first radiobiological investigations in space to the insurance of radiation safety for helicopter air crews who took part in cleaning-up operations of consequences of the Chernobyl accident. The workers of the Radiobiological Laboratory have performed some research theoretical and practical tasks in the interests of aviation and space, civil and military medicine: the impact of gravitation and radiation on genetic structures has been studied, a radiation safety system for vehicles of different use has been developed, new principles in the standardization of EMF for radiofrequency and microwave bands have been proposed, the new radioprotective agent indralin (B, B-190) has been discovered, which is accepted for supply and used in rotary wing aircraft pilots during liquidation works at the Chernobyl atomic power station. New experimental data on the combined effects of radiation and non-radiation flight factors have been obtained. Basically new data on the mechanism of action of ionizing and non-ionizing radiation on the brain have been also gained, a system for assessing the health and rehabilitation of pilots that cleaned-up the Chernobyl accident has been developed. Professor Pavel Petrovich Saksonov, RF Honoured Scientist, has the honour to create a school of aerospace radiobiology. PMID:8963185

  13. Guidelines to Clinical Experiences in Teacher Education. Position Paper 3.

    ERIC Educational Resources Information Center

    Association of Teacher Educators, Reston, VA.

    This document, a collection of guidelines for clinical experience in teacher education, is divided into eight sections with two appendixes. These sections are as follows: Frame of Reference; Aims of Clinical Experiences, which stresses that the experiences should be complementary to the humanistic, behavioral, and pedagogical studies for becoming…

  14. Minimally invasive thymectomy: the Mayo Clinic experience

    PubMed Central

    Rowse, Phillip G.; Roden, Anja C.; Corl, Frank M.; Allen, Mark S.; Cassivi, Stephen D.; Nichols, Francis C.; Shen, K. Robert; Wigle, Dennis A.

    2015-01-01

    Background The prevalence of minimally invasive thymectomy (MIT) is increasing and may have significant benefit to patients in terms of morbidity and post-operative recovery. Our aim was to review the Mayo Clinic experience of MIT. Methods We reviewed data from all MIT cases collected in a prospectively maintained database from January 1995 to February 2015. Data were collected regarding patient demographics, perioperative management and patient outcomes. Results A total of 510 thymectomies were performed in 20 years. Fifty-six patients underwent MIT (45 video-assisted thoracoscopy, 11 robotic-assisted). The median age was 55 years (range, 23-87 years) with male to female ratio of 25:31. Thymoma was the main pathologic diagnosis in 27/56 patients (48%), with 11/27 (41%) associated with myasthenia gravis (MG), and 16/27 (59%) non-MG. Other pathologies included 1/56 (2%) of each teratoma, lymphoma, lymphangioma, carcinoma and thymolipoma. There were 3/56 (5%) atrophic glands, 4/56 (7%) cysts, 6/56 (11%) benign glands and 11/56 (20%) hyperplastic. Mean blood loss (mL) and operative time (min) were significantly lower in the video-assisted thoracoscopic surgery (VATS) group compared to robotic (65±41 vs. 160±205 mL, P=0.04 and 102±39 vs. 178±53 min, P=0.001, respectively). There was no 30-day mortality. Post-operative morbidity occurred in 7/45 (16%) VATS patients (phrenic nerve palsy 7%, pericarditis 4%, atrial fibrillation 2%, pleural effusion 2%) and 1/11 (9%) robotic (urinary retention requiring self-catheterization). Reoperation was required in 1/3 of VATS patients with phrenic nerve palsy. There was no significant difference in length of hospital stay [VATS 1.5 days (range, 1-4 days) and robotic 2 days (range, 1-5 days) VATS; P=0.05]. Mean follow-up was 18.4 months (range, 1-50.4 months) with no tumor recurrences. Conclusions MIT can be performed with low morbidity and mortality. VATS is associated with reduced blood loss, operative times and earlier hospital

  15. Workshop on radiobiological effectiveness of neutrons

    SciTech Connect

    Stapleton, G.E.; Thomas, R.G.; Thiessen, J.W.

    1985-09-01

    The radiobiological effectiveness (RBE) of neutrons has become the subject of some heated discussions in both scientific and radiation-protection oriented communities. This has become especially so since the realization that neutron exposures of A-bomb survivors in Hiroshima were considerably lower than previously assumed, thus ''devaluating'' the importance of what we thought was a solid human data base. At the same time, more recent data from radiobiological research appeared to indicate that, at least for some biological endpoints, the RBE of neutrons at low doses and low dose rates was increased dramatically compared to the RBE at higher dose and dose rates. As a consequence, the protection of health against neutrons became a subject of some urgency. The objective of this workshop was to evaluate the existing data base in order to determine the need for additional research in this field. 22 refs., 3 figs., 6 tabs.

  16. Workshop on Radiobiological Effectiveness of Neutrons

    NASA Astrophysics Data System (ADS)

    Stapleton, G. E.; Thomas, R. G.; Thiessen, J. W.

    1985-09-01

    The radiobiological effectiveness (RBE) of neutrons has become the subject of some heated discussions in both scientific and radiation-protection oriented communities. This has become especially so since the realization that neutron exposures of A-bomb survivors in Hiroshima were considerably lower than previously assumed, thus devaluating the importance of what we thought was a solid human data base. At the same time, more recent data from radiobiological research appeared to indicate that, at least for some biological endpoints, the RBE of neutrons at low doses and low dose rates was increased dramatically compared to the RBE at higher dose and dose rates. As a consequence, the protection of health against neutrons became a subject of some urgency. The objective of this workshop was to evaluate the existing data base in order to determine the need for additional research in this field.

  17. The Importance of Early Experiences: Clinical, Research, and Policy Perspectives

    ERIC Educational Resources Information Center

    Zeanah, Charles H.

    2009-01-01

    The degree to which early adverse experiences exert long term effects on development and how much early adversity may be overcome through subsequent experiences are important mental health questions. The clinical, research and policy perspectives on these questions lead to different answers. From a clinical perspective, change is always possible,…

  18. The Instructional Technology Clinical Experience: Expectations and Realities.

    ERIC Educational Resources Information Center

    Cennamo, Katherine S.; Holmes, Glen

    This paper provides an overview of the IT (Instructional Technology) Clinical graduate course at Virginia Tech and compares the perceived reality of the Clinical experience, in terms of benefits and concerns, with students' initial expectations. The paper begins with a discussion of the IT Clinical plan, the sociology of the learning environment…

  19. Clinical profile and practice experience of almotriptan.

    PubMed

    Gendolla, A

    2004-01-01

    Patients expect their acute migraine treatment to have a rapid onset of action, achieve complete pain relief that is sustained for 24 h, and to have a good tolerability profile. Almotriptan has a favourable pharmacokinetic profile that translates clinically to a rapid onset of action and consistent absorption regardless of age, sex, food intake and status of the acute migraine attack. In addition, almotriptan is not associated with any clinically relevant drug-drug interactions. Pain-free status at 2 h postdose is achieved by approximately 39% of patients receiving almotriptan in clinical trials. Recurrence of headaches within 24 h is low with almotriptan (<22%). Almotriptan has a sustained pain-free rate of 25-27%, which in a meta-analysis of triptans was superior to sumatriptan 100 mg. Almotriptan therapy is associated with a low incidence of adverse events, including those affecting the central nervous system and chest. PMID:15595990

  20. Collaborative Clinical Practice: An Alternate Field Experience

    ERIC Educational Resources Information Center

    Dee, Amy Lynn

    2012-01-01

    Teacher education in the 21st century is encountering increased scrutiny, added pressure, and escalating external regulations but does not have practical and immediate solutions for improving programs. While reforms in teacher education call for additional and improved clinical practice for candidates, through strengthened partnerships with local…

  1. A Simulated Interprofessional Rounding Experience in a Clinical Assessment Course

    PubMed Central

    Shrader, Sarah; McRae, Lacy; King, William M.; Kern, Donna

    2011-01-01

    Objective To implement a simulated interprofessional rounding experience using human patient simulators as a required activity for third-year pharmacy students in a clinical assessment course. Design Interprofessional student teams consisting of pharmacy, medical, and physician assistant students participated in a simulated interprofessional rounding experience in which they provided comprehensive medical care for a simulated patient in an inpatient setting. Assessment Students completed a survey instrument to assess interprofessional attitudes and satisfaction before and after participation in the simulated interprofessional rounding experience. Overall student attitudes regarding interprofessional teamwork and communication significantly improved; student satisfaction with the experience was high and students’ self-perceived clinical confidence improved after participation. The mean team clinical performance scores were 65% and 75% for each simulated interprofessional rounding experience. Conclusion Incorporating a simulated interprofessional rounding experience into a required clinical assessment course improved student attitudes regarding interprofessional teamwork and was associated with high student satisfaction. PMID:21769137

  2. Mesenchymal stem cells: from experiment to clinic

    PubMed Central

    2011-01-01

    There is currently much interest in adult mesenchymal stem cells (MSCs) and their ability to differentiate into other cell types, and to partake in the anatomy and physiology of remote organs. It is now clear these cells may be purified from several organs in the body besides bone marrow. MSCs take part in wound healing by contributing to myofibroblast and possibly fibroblast populations, and may be involved in epithelial tissue regeneration in certain organs, although this remains more controversial. In this review, we examine the ability of MSCs to modulate liver, kidney, heart and intestinal repair, and we update their opposing qualities of being less immunogenic and therefore tolerated in a transplant situation, yet being able to contribute to xenograft models of human tumour formation in other contexts. However, such observations have not been replicated in the clinic. Recent studies showing the clinical safety of MSC in several pathologies are discussed. The possible opposing powers of MSC need careful understanding and control if their clinical potential is to be realised with long-term safety for patients. PMID:21902837

  3. Introductory Laboratory Exercises in Radiobiology

    ERIC Educational Resources Information Center

    Williams, J. R. Parry; Servant, D. M.

    1970-01-01

    Describes experiments suitable for introducing use of radioisotopes in biology. Includes demonstrations of tracing food chains, uptake of ions by plants, concentration of elements by insects, tracing photosynthetic reactions, activation analysis of copper, and somatic and genetic effects. Uses autoradiographic and counting techniques. (AL)

  4. Assessing the shift of radiobiological metrics in lung radiotherapy plans using 2D gamma index

    PubMed Central

    Balosso, Jacques

    2016-01-01

    Background The purpose of this work is to investigate the 2D gamma (γ) maps to illustrate the change of radiobiological outcomes for lung radiotherapy plans and evaluate the correlation between tumor control probability (TCP), normal tissue complication probability (NTCP) with γ passing rates (γ-rates). Methods Nine patients with lung cancer were used. The doses were calculated using Modified Batho method integrated with pencil beam convolution (MB-PBC) and anisotropic analytical algorithm (AAA) using the same beam arrangements and prescription dose. The TCP and NTCP were estimated, respectively, using equivalent uniform dose (EUD) model and Lyman-Kutcher-Burman (LKB) model. The correlation between ΔTCP or ΔNTCP with γ-rates, from 2%/2 and 3%/3 mm, were tested to explore the best correlation predicting the relevant γ criteria using Spearman’s rank test (ρ). Wilcoxon paired test was used to calculate P value. Results TCP value was significantly lower in the recalculated AAA plans as compared to MB plans. However, AAA predicted more NTCP on lung pneumonitis according to the LKB model and using relevant radiobiological parameters (n, m and TD50) for MB-PBC and AAA, with P=0.03. The data showed a weak correlation between radiobiological metrics with γ-rates or γ-mean, ρ<0.3. Conclusions AAA and MB yield different TCP values as well as NTCP for lung pneumonitis based on the LKB model parameters. Therefore, 2D γ-maps, generated with 2%/2 or 3%/3 mm, could illustrate visual information about the radiobiological changes. The information is useful to evaluate the clinical outcome of a radiotherapy treatment and to approve the treatment plan of the patient if the dose constraints are respected. On the other hand, the γ-maps tool can be used as quality assurance (QA) process to check the predicted TCP and NTCP from radiobiological models. PMID:27413708

  5. Clinical nurse specialist regulation: the Maryland experience.

    PubMed

    Thurman, Paul

    2015-01-01

    High-quality care will continue to be a driver in the evolution of today's health care environment. Ensuring effective, cost-conscious, quality care is the core of clinical nurse specialist (CNS) practice. The CNS practice varies by state, depending on each state's Nurse Practice Act. Some states have separate scopes of practice for CNSs, including prescriptive authority, whereas some states do not recognize CNS practice as different from the practice of the registered nurse. The journey to state recognition and title protection for the CNS role in the state of Maryland is described. PMID:25594481

  6. Standards and Methodologies for Characterizing Radiobiological Impact of High-Z Nanoparticles

    PubMed Central

    Subiel, Anna; Ashmore, Reece; Schettino, Giuseppe

    2016-01-01

    Research on the application of high-Z nanoparticles (NPs) in cancer treatment and diagnosis has recently been the subject of growing interest, with much promise being shown with regards to a potential transition into clinical practice. In spite of numerous publications related to the development and application of nanoparticles for use with ionizing radiation, the literature is lacking coherent and systematic experimental approaches to fully evaluate the radiobiological effectiveness of NPs, validate mechanistic models and allow direct comparison of the studies undertaken by various research groups. The lack of standards and established methodology is commonly recognised as a major obstacle for the transition of innovative research ideas into clinical practice. This review provides a comprehensive overview of radiobiological techniques and quantification methods used in in vitro studies on high-Z nanoparticles and aims to provide recommendations for future standardization for NP-mediated radiation research. PMID:27446499

  7. Clinical experience with recently approved antibiotics.

    PubMed

    Paterson, David L

    2006-10-01

    The advent of vancomycin-resistant enterococci in the 1990s and the threat posed by vancomycin resistance in Staphylococcus aureus led to the development of several new antimicrobial agents active against these pathogens. Quinupristin/dalfopristin was the first such drug to be commercially available but adverse effects have meant that the drug is now rarely used. Linezolid, the first antimicrobial of the oxazolidinone class, has met with more widespread use and has both an intravenous and an oral formulation. Daptomycin is a lipopeptide antimicrobial that is rapidly bactericidal against S. aureus. It is effective in the therapy of S. aureus bloodstream infections but is inactivated by pulmonary surfactant, making it of no use in the therapy of pneumonia. Tigecycline, by contrast, is bacteriostatic against most pathogens but has a broad spectrum of antimicrobial activity and has enhanced penetration into many tissues. Other new antibiotics (dalbavancin, telavancin, ceftobiprole and doripenem) are currently under clinical development and hold promise for widespread clinical use in the next decade. PMID:16904377

  8. Ankylosing Spondylitis: A rheumatology clinic experience

    PubMed Central

    Ahsan, Tasnim; Erum, Uzma; Jabeen, Rukhshanda; Khowaja, Danish

    2016-01-01

    Objective: To determine the frequency, demographics, laboratory and radiological features in patients with Ankylosing Spondylitis. Methods: This is a retrospective analysis of prospectively collected data of patients with a diagnosis of Ankylosing Spondylitis (AS), based on Modified New York criteria. The study was conducted at the Rheumatology Clinic of Jinnah Postgraduate Medical Centre (JPMC), from February 2004 to February 2014. Detailed history, examination and laboratory investigations were recorded in a pre-designed structured proforma. The frequency, demographic characteristics, extra-articular features and associated co-morbidities were studied. Results: A total of 603 patients were registered in our Rheumatology Clinic during this period, with a definitive diagnosis of inflammatory rheumatological disorders. Out of these, Ankylosing Spondylitis (AS) was diagnosed in 32 (5.3%) patients. 24 were male and 8 patients were female. The commonest affected age group was between 21-40 years. Majority of the patients belonged to Pathan ethnicity. Conclusion: The demographic features of AS are same as reported in earlier studies from other parts of the world. The predominance of AS in specific ethnic groups is a fact that needs to be studied. Larger studies are required for clarifying the triggers of this disease. It often leads to severe disability, hence an early diagnosis and prompt treatment is required for better disease control and quality of life. PMID:27182241

  9. Paranasal sinus mucoceles: our clinical experiments

    PubMed Central

    Topdag, Murat; Iseri, Mete; Sari, Fatih; Erdogan, Selvet; Keskin, I Gurkan

    2015-01-01

    Objectives: We present the clinical and radiological features, treatment protocols, and medium-long-term results of our patients following surgery for paranasal sinus mucocele, along with a review of the relevant literature. Materials and methods: A total of 18 patients (11 women and 7 men) who underwent surgery for paranasal sinus mucocele at Kocaeli University Faculty of Medicine, Department of Otolaryngology, between 2006 and 2013 were examined retrospectively. The mean patient age was 41 (range 4-73). Demographic and radiological features, symptoms, treatment protocols, and postoperative outcomes were recorded. Results: The most frequently affected sinus was the maxillary sinus (n=9, 50%) followed by the frontal sinus (n=6, 33%) and sphenoidal sinus (n=3, 16%). The main symptom was headache. Endoscopic marsupialization of the mucocele was applied in all 18 patients, while frontal sinus exploration with the osteoplastic flap procedure was performed in one patient and the Caldwell-Luc operation was performed in another patient. The Caldwell-Luc procedure was subsequently required in one patient (6%) and endoscopic revision surgery was required in another patient (6%). Conclusion: Sinus mucocele that enlarges, eroding the surrounding bone tissue, and induces various clinical symptoms due to the impression of the expansile mass, is treated surgically, and must be planned carefully to prevent serious complications. PMID:26770462

  10. Neural stimulation: clinical and laboratory experiences.

    PubMed

    Pudenz, R H

    1993-03-01

    This is a report of some of the experiences of the author and his associates with electrical stimulation of the animal and human nervous systems. It was presented as a personal history rather than a review of recent investigations and publications concerned with safe and effective stimulation of neural tissue with the ultimate goals of developing neural prostheses. Much of the information presented herein has been published. PMID:8456389

  11. [Euthanasia--experiences from Norwegian pain clinics].

    PubMed

    Meidell, N K; Naess, A C

    1998-10-10

    This survey focuses on the subject of euthanasia. A questionnaire was sent to 90 doctors working in pain clinics in Norwegian hospitals. 60 doctors (67%) returned the questionnaire. Only 18 doctors (30%) had ever received a request for euthanasia. The patients who requested euthanasia suffered from refractory pain, depression, fear of pain and fear of becoming helpless. 67% of the doctors were satisfied with the present Norwegian law, while 13% favoured a liberalization of the law. Only 5% were willing to comply with the patient's request for euthanasia under today's law. One third of the doctors would leave the decision to an officially appointed "board" if euthanasia were to become legalized. A majority wanted a doctor to commit the actual procedure, but there were also suggestions that a lawyer or other lay person should carry out the act of euthanasia. Our conclusion is that the closer the patient-doctor relationship is, the more opposed the doctor is to euthanasia. PMID:9816949

  12. Clinical experience with Angiojet: a comprehensive review.

    PubMed

    Ierardi, A M; Xhepa, G; Piffaretti, G; Bacuzzi, A; Tozzi, M; Carbone, M; Barile, A; Squillaci, E; Fonio, P; Brunese, L; Carrafiello, G

    2015-12-01

    The development of various sophisticated mechanical thrombectomy devices and the amassed experience of physicians in minimal invasive therapy produced a paradigm shift in vascular access management toward percutaneous declotting procedures, using pharmaceutical thrombolysis, mechanical thrombectomy, balloon thrombectomy, and a combination of the above techniques. In this setting, in the last years, AngioJet™ (Possis, Minneapolis, MN, USA) rheolytic thrombectomy (RT) showed an increasing use in emergency and election patients. The purpose of this review is to present the current status of percutaneous rheolytic thrombectomy in different fields of applications. PMID:26498886

  13. Operation and Maintenance of the National Radiobiology Archives

    SciTech Connect

    Dr. Anthony C. James; Stacey L. McCord

    2012-03-07

    The National Radiobiology Archives (NRA) are an archival program, started in 1989, to collect, organize and maintain data, laboratory notebooks, and animal tissue specimens from government (Department of Energy and its predecessor agencies) sponsored radiobiology life-span animal studies. These unique records, histopathology slides and paraffin embedded tissue blocks are maintained in a central facility and are available for further research study. The materials include electronic and paper records for each of more than 6,000 life-span-observations on dogs as well as details of major studies involving nearly 30,000 mice. Although these studies were performed over many years and at different laboratories with differing data management systems, the NRA has translated them into a standardized set of relational database tables. These can be distributed to interested individuals on written request. Specific Aims are: (1) To Maintain the Archive of Written Records from the Animal Experiments - The USTUR continued to maintain the NRA archives which consist of approximately 175 storage boxes containing laboratory notebooks, animal exposure records, animal pathologic records, and radiographs. These were stored in a 6,000 square foot leased facility in Richland, WA. Additionally, through a collaboration with Pacific Northwest National Laboratory's (PNNL) Low Dose Program, many of these records were scanned into digital files. These totaled 34 GB of data, which are saved in 2,407 separate PDF files that are organized by box number and animal identification number. (2) To Maintain the Archive of Animal Tissues at Washington State University - The USTUR continued to house the NRA dog tissue collection in the leased facility. The NRA tissue collection consisted of pathology slides and tissue blocks. Approximately 25% of the laboratory facility was dedicated to the storage of the NRA materials. (3) To Organize the Datasets of These Animals in the Context of Other Datasets so That

  14. Radiobiological studies using gamma and x rays.

    SciTech Connect

    Potter, Charles Augustus; Longley, Susan W.; Scott, Bobby R.; Lin, Yong; Wilder, Julie; Hutt, Julie A.; Padilla, Mabel T.; Gott, Katherine M.

    2013-02-01

    There are approximately 500 self-shielded research irradiators used in various facilities throughout the U.S. These facilities use radioactive sources containing either 137Cs or 60Co for a variety of biological investigations. A report from the National Academy of Sciences[1] described the issues with security of particular radiation sources and the desire for their replacement. The participants in this effort prepared two peer-reviewed publications to document the results of radiobiological studies performed using photons from 320-kV x rays and 137Cs on cell cultures and mice. The effectiveness of X rays was shown to vary with cell type.

  15. THREE YEARS CLINICAL EXPERIENCE WITH INTESTINAL TRANSPLANTATION

    PubMed Central

    Abu-Elmagd, Kareem; Todo, Satoru; Tzakis, Andreas; Reyes, Jorge; Nour, Bakr; Furukawa, Hiroyuki; Fung, John J.; Demetris, Anthony; Starzl, Thomas E.

    2009-01-01

    BACKGROUND After the successful evolution of hepatic transplantation during the last decade, small bowel and multivisceral transplantation remains the sole elusive achievement for the next era of transplant surgeons. Until recently, and for the last thirty years, the results of the sporadic attempts of intestinal transplantation worldwide were discouraging because of unsatisfactory graft and patient survival. The experimental and clinical demonstration of the superior therapeutic efficacy of FK 506, a new immunosuppressive drug, ushered in the current era of small bowel and multivisceral transplantation with initial promising results. STUDY DESIGN Forty-three consecutive patients with short bowel syndrome, intestinal insufficiency, or malignant tumors with or without associated liver disease, were given intestinal (n=15), hepatic and intestinal (n=21), or multivisceral allografts that contained four or more organs (n=7). Treatment was with FK 506 based immunosuppression. The ascending and right transverse colon were included with the small intestine in 13 of the 43 grafts, almost evenly distributed between the three groups. RESULTS After six to 39 months, 30 of the 43 patients are alive, 29 bearing grafts. The most rapid convalescence and resumption of diet, as well as the highest three month patient survival (100 percent) and graft survival (88 percent) were with the isolated intestinal procedure. However, this advantage was slowly eroded during the first two postoperative years, in part because the isolated intestine was more prone to rejection. By the end of this time, the best survival rate (86 percent) was with the multivisceral procedure. With all three operations, most of the patients were able to resume diet and discontinue parenteral alimentation, and in the best instances, the quality of life approached normal. However, the surveillance and intensity of care required for these patients for the first year, and in most instances thereafter, was very high

  16. Team Preceptorship Model: A Solution for Students' Clinical Experience

    PubMed Central

    Cooper Brathwaite, Angela; Lemonde, Manon

    2011-01-01

    There is a shortage of registered nurses in developed countries, and this shortage is due to the aging nursing workforce, demand for healthcare services, and shortage of nursing professors to teach students. In order to increase the number of clinical placements for nursing students, the authors developed and implemented a collaborative preceptorship model between a Canadian University and Public Health Department to facilitate the clinical experiences of Bachelor of Science of Nursing (BScN) students. This paper describes the Team Preceptorship Model which guided the clinical experience of nine students and 14 preceptors. It also highlights the model's evaluation, strengths, and limitations. PMID:21994893

  17. O. R. Clinical Experience: Catalyst For Student Learning

    ERIC Educational Resources Information Center

    Nolan, Mary Gill

    1976-01-01

    Active participation in a 12-hour operating room experience seemed to provide one group of medical-surgical nursing students with a broad range of clinical nursing experiences leading to rapid, integrated learning of knowledge and skills and increased self-confidence. (Author)

  18. Pre-clinical medical student experience in a pediatric pulmonary clinic

    PubMed Central

    Saba, Thomas G.; Hershenson, Marc B.; Arteta, Manuel; Ramirez, Ixsy A.; Mullan, Patricia B.; Owens, Sonal T.

    2015-01-01

    Objective Our objective was to evaluate the educational value of introducing pre-clinical medical students to pediatric patients and their families in a subspecialty clinic setting. Methods First- and second-year medical students at the University of Michigan seeking clinical experience outside of the classroom attended an outpatient pediatric pulmonary clinic. Evaluation of the experience consisted of pre- and post-clinic student surveys and post-clinic parent surveys with statements employing a four-point Likert scale as well as open-ended questions. Results Twenty-eight first-year students, 6 second-year students, and 33 parents participated in the study. Post-clinic statement scores significantly increased for statements addressing empathic attitudes, confidence communicating with children and families, comfort in the clinical environment, and social awareness. Scores did not change for statements addressing motivation, a sense of team membership, or confidence with career goals. Students achieved their goals of gaining experience interacting with patients, learning about pulmonary diseases, and observing clinic workflow. Parents felt that they contributed to student education and were not inconvenienced. Conclusions Students identified several educational benefits of exposure to a single pediatric pulmonary clinic. Patients and families were not inconvenienced by the participation of a student. Additional studies are warranted to further investigate the value of this model of pre-clinical medical student exposure to subspecialty pediatrics. PMID:26547081

  19. Clinical Needs Finding: Developing the Virtual Experience, A Case Study

    PubMed Central

    Mittal, Vaishali; Thompson, Megan; Altman, Stuart M; Taylor, Peter; Summers, Alexander; Goodwin, Kelsey; Louie, Angelique Y

    2013-01-01

    We describe an innovative program at the University of California, Davis for students to engage in clinical needs finding. Using a team-based approach, students participated in clinical rotations to observe firsthand the needs of clinicians at the university affiliated medical center. The teams were asked to develop documentary-style videos to capture key experiences that would allow future viewers to use the videos as “virtual” clinical rotations. This was conceived as a strategy to allow students in prohibitively large classes, or students in programs at institutions without associated medical or veterinary school programs, to experience clinical rotations and perform needs assessments. The students' perspectives on the experience as well as instructor analysis of best practices for this type of activity are presented and discussed. We found that the internship experience was valuable to the students participating, by not only introducing the practice of needs finding but for increasing the students' confidence in the practice of engineering design and their ability to work independently. The videos produced were of such high quality that instructors from other institutions have requested copies for instructional use. Virtual clinical rotations through video experiences may provide a reasonable substitute for students who do not have the ability to participate in rotations in person. PMID:23483373

  20. The potential of californium-252 in radiotherapy. Preclinical measurements in physics and radiobiology.

    PubMed

    Hall, E J; Rossi, H

    1975-10-01

    Californium-252 is a man-made radionuclide (half-life 2-65 years) which emits a mixture of neutrons and gamma rays. It is used in radiotherapy as an alternative to radium and extends the potential benefits of neutrons to interstitial and intracavitary applications. Gamma rays account for a variable proportion of the dose (30 to 50 per cent), depending on the source filtration and the distance from the source. Dosimetry is complicated by this mixture of neutrons and gamma rays. However, measurements with paired ion-chambers, together with Monte-Carlo calculations, have produced dosimetric data that are adequate for clinical use. Many determinations of the oxygen enhancement ratio (OER) have been reported. At the low dose-rates characteristic of interstitial implants, the OER is about 1-5. This is essentially the figure for fast neutrons alone, since at very low dose-rates the contribution of the gamma rays to the biological effect is negligible. As the dose increases, there is a corresponding rise in the OER because the gamma ray contribution can no longer be ignored. The OER is likely to be about 1-8 if 252Cf is used in intracavity treatments and 2-0 if used in "acute" exposures in devices such as the Cathetron. The relative biological effectivenesss (RBE) varies with dose-rate, and with the biological system used to measure it. Radiobiological experiments indicate that 6,000 rads of radium gamma rays in seven days is equivalent to 890 rads of 252Cf neutrons delivered in approximately the same overall time. This figure was suggested some years ago as an interim guide-line until sufficient clinical experience is accumulated. PMID:811295

  1. 3-D Imaging Based, Radiobiological Dosimetry

    PubMed Central

    Sgouros, George; Frey, Eric; Wahl, Richard; He, Bin; Prideaux, Andrew; Hobbs, Robert

    2008-01-01

    Targeted radionuclide therapy holds promise as a new treatment against cancer. Advances in imaging are making it possible to evaluate the spatial distribution of radioactivity in tumors and normal organs over time. Matched anatomical imaging such as combined SPECT/CT and PET/CT have also made it possible to obtain tissue density information in conjunction with the radioactivity distribution. Coupled with sophisticated iterative reconstruction algorithims, these advances have made it possible to perform highly patient-specific dosimetry that also incorporates radiobiological modeling. Such sophisticated dosimetry techniques are still in the research investigation phase. Given the attendant logistical and financial costs, a demonstrated improvement in patient care will be a prerequisite for the adoption of such highly-patient specific internal dosimetry methods. PMID:18662554

  2. BNL ACCELERATOR-BASED RADIOBIOLOGY FACILITIES

    SciTech Connect

    LOWENSTEIN,D.I.

    2000-05-28

    For the past several years, the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (USA) has provided ions of iron, silicon and gold, at energies from 600 MeV/nucleon to 10 GeV/nucleon, for the US National Aeronautics and Space Administration (NASA) radiobiology research program. NASA has recently funded the construction of a new dedicated ion facility, the Booster Applications Facility (BAF). The Booster synchrotron will supply ion beams ranging from protons to gold, in an energy range from 40--3,000 MeV/nucleon with maximum beam intensities of 10{sup 10} to 10{sup 11} ions per pulse. The BAF Project is described and the future AGS and BAF operation plans are presented.

  3. Nursing Students' Clinical Experience With Death: A Pilot Study.

    PubMed

    Heise, Barbara A; Gilpin, Laura C

    2016-01-01

    Although debriefing in simulation settings is routine in nursing education, debriefing does not routinely take place in clinical settings with nursing students after a patient has died. This pilot study sought to explore nursing students' perceptions of their first experience with the death of a patient. Students reported emotional distress and feelings of inadequacy with regard to communicating with and supporting the family of the dying patient. Only half the students sampled reported debriefing by their clinical instructor or staff. Nurse educators must include debriefing and student support following a patient death in the clinical setting. PMID:27209870

  4. Bystander effects and their implications for clinical radiation therapy: Insights from multiscale in silico experiments.

    PubMed

    Powathil, Gibin G; Munro, Alastair J; Chaplain, Mark A J; Swat, Maciej

    2016-07-21

    Radiotherapy is a commonly used treatment for cancer and is usually given in varying doses. At low radiation doses relatively few cells die as a direct response to radiation but secondary radiation effects, such as DNA mutation or bystander phenomena, may affect many cells. Consequently it is at low radiation levels where an understanding of bystander effects is essential in designing novel therapies with superior clinical outcomes. In this paper, we use a hybrid multiscale mathematical model to study the direct effects of radiation as well as radiation-induced bystander effects on both tumour cells and normal cells. We show that bystander responses play a major role in mediating radiation damage to cells at low-doses of radiotherapy, doing more damage than that due to direct radiation. The survival curves derived from our computational simulations showed an area of hyper-radiosensitivity at low-doses that are not obtained using a traditional radiobiological model. PMID:27084360

  5. Dental Students' Clinical Expectations and Experiences Treating Persons with Disabilities.

    PubMed

    Perusini, Darsi J; Llacuachaqui, Marcia; Sigal, Michael J; Dempster, Laura J

    2016-03-01

    Persons with disabilities (PWDs) have a disproportionate level of dental disease relative to the general population. Access to care is a cause along with dentists' willingness to treat PWDs. The aim of this study was to investigate the expectations and experiences of dental students in providing treatment to these patients in a hospital-based dental clinic for PWDs. Senior dental students at the Faculty of Dentistry, University of Toronto (n=92) were surveyed prior to (Phase I) and at the end of (Phase II) mandatory clinical rotations at the Mount Sinai Hospital's Dentistry Clinic for Persons with Special Needs. Response rates were 88% for Phase I and 58% for Phase II. Before the rotations, 70% of the respondents reported little or no experience with PWDs, and 46% said they did not feel comfortable providing basic dental treatment to PWDs. However, in Phase II, significantly more students reported being comfortable than in Phase I (p=0.001). Overall, the majority of respondents (Phase I 95%; Phase II 98%) indicated they would at least attempt to provide basic dental care to PWDs after graduation. The majority also identified the opportunity to provide care and interact with PWDs as the most enjoyable aspect of their experience at the clinic. They reported that the experience helped reduce their concerns about treating PWDs including being more realistic about the time required and ideal quality of the treatment they could provide. These results suggest that their experience in the clinic significantly increased students' comfort in treating PWDs. The respondents expressed a willingness to treat PWDs once graduated and generally identified their experience as being more positive than their expectations. PMID:26933105

  6. A solo hospital librarian's experience in clinical informatics.

    PubMed

    Miles, Alisha

    2015-01-01

    This column reviews some of a solo librarian's experiences that led to involvement with the hospital Clinical Informatics Team. This included work on the electronic health record (EHR), computerized physician order entry (CPOE) system, development of order sets, and participation in the Physician Technology Committee. PMID:25927515

  7. Teachers' Clinical Experiences and Attitudes toward Technology Inclusion

    ERIC Educational Resources Information Center

    Paganelli, Andrea Lynch

    2010-01-01

    The purpose of this qualitative multisite case study is to examine participants' attitudes toward technology, types of technology available for participant use, and the extent to which technology is used by preservice and mentor teachers during clinical experiences. Research supports the benefit of improved attitudes toward technology integration…

  8. The Student Trainer Clinical Experience at Lock Haven State College.

    ERIC Educational Resources Information Center

    Tomasi, David

    An integral part of the clinical experience for athletic trainers at Lock Haven State College (Pennsylvania) is training in first aid and learning to evaluate not only sport-related injuries but all injuries. Thorough knowledge is expected of athletic trainers in the areas of cardiopulmonary resuscitation, first aid, and treatment of…

  9. [Cryodevitalization of the mandible. The initial clinical experience].

    PubMed

    Eckelt, U; Lerch, H; Franke, W G

    1990-01-01

    There is given a report about first clinical experiences in the partial cryodevitalization of the mandible. 3 tumor-bearing patients were treated. The resection of the mandible was not necessary. The process of revitalisation was observed by bone scanning. PMID:2150462

  10. Time Keeps on Ticking: The Experience of Clinical Judgment

    ERIC Educational Resources Information Center

    Spengler, Paul M.; White, Michael J.; Aegisdottir, Stefania; Maugherman, Alan S.

    2009-01-01

    The reactions by Ridley and Shaw-Ridley (EJ832451) and Lichtenberg (EJ832452) to the authors' meta-analysis on the effects of experience on judgment accuracy add positively to what is hoped will become an ever more focused discourse on this most basic question: How can mental health clinical decision making be improved? In this rejoinder, the…

  11. Challenging clinical learning environments: experiences of undergraduate nursing students.

    PubMed

    O'Mara, Linda; McDonald, Jane; Gillespie, Mary; Brown, Helen; Miles, Lynn

    2014-03-01

    Clinical learning is an essential component of becoming a nurse. However at times, students report experiencing challenging clinical learning environments (CCLE), raising questions regarding the nature of a challenging clinical learning environment, its impact on students' learning and how students might respond within a CCLE. Using an Interpretive Descriptive study design, researchers held focus groups with 54 students from two Canadian sites, who self-identified as having experienced a CCLE. Students defined a CCLE as affected by relationships in the clinical area and by the context of their learning experiences. CCLE decreased students' learning opportunities and impacted on them as persons. As students determined which relationships were challenging, they tapped other resources and they used strategies to rebuilt, reframe, redirect and/or retreat relative to the specific challenge. Relationships also acted as buffers to unsupportive practice cultures. Implications for practice and research are addressed. PMID:24063792

  12. E-health stakeholders experiences with clinical modelling and standardizations.

    PubMed

    Gøeg, Kirstine Rosenbeck; Elberg, Pia Britt; Højen, Anne Randorff

    2015-01-01

    Stakeholders in e-health such as governance officials, health IT-implementers and vendors have to co-operate to achieve the goal of a future-proof interoperable e-health infrastructure. Co-operation requires knowledge on the responsibility and competences of stakeholder groups. To increase awareness on clinical modeling and standardization we conducted a workshop for Danish and a few Norwegian e-health stakeholders' and made them discuss their views on different aspects of clinical modeling using a theoretical model as a point of departure. Based on the model, we traced stakeholders' experiences. Our results showed there was a tendency that stakeholders were more familiar with e-health requirements than with design methods, clinical information models and clinical terminology as they are described in the scientific literature. The workshop made it possible for stakeholders to discuss their roles and expectations to each other. PMID:25991150

  13. Fostering new relational experience: clinical process in couple psychotherapy.

    PubMed

    Marmarosh, Cheri L

    2014-03-01

    One of the most critical goals for couple psychotherapy is to foster a new relational experience in the session where the couple feels safe enough to reveal more vulnerable emotions and to explore their defensive withdrawal, aggressive attacking, or blaming. The lived intimate experience in the session offers the couple an opportunity to gain integrative insight into their feelings, expectations, and behaviors that ultimately hinder intimacy. The clinical processes that are necessary include empathizing with the couple and facilitating safety within the session, looking for opportunities to explore emotions, ruptures, and unconscious motivations that maintain distance in the relationship, and creating a new relational experience in the session that has the potential to engender integrative insight. These clinical processes will be presented with empirical support. Experts from a session will be used to highlight how these processes influence the couple and promote increased intimacy. (PsycINFO Database Record (c) 2014 APA, all rights reserved). PMID:24059733

  14. Rubrics for clinical evaluation: objectifying the subjective experience.

    PubMed

    Isaacson, Julie J; Stacy, Annette S

    2009-03-01

    Rubrics have historically been used in secondary and higher education to evaluate specific assignments or tasks. There is little mention of rubrics in the nursing literature, particularly in the area of clinical evaluation. A strong case can be made for expanding the traditional use of a rubric to include its validity with clinical evaluation. Clinical evaluation remains a challenge, even for seasoned faculty. Faculty and students often interpret clinical course objectives differently. Coupled with this concern is the subjectivity of the evaluation. The use of "novice" clinical faculty, who inevitably struggle with discerning and justifying anything but stellar student performance, further compounds these issues. Rubrics also facilitate the grading experience for faculty and students. Faculty often find themselves making repetitive written comments to students. These comments can be incorporated into the rubric, thus shortening grading time while increasing the quality and quantity of instructor feedback. When clarified in a rubric, course objectives become "real". Student benefits include increased critical thinking and a more realistic approach to self-evaluation. Clinical rubrics can be developed from existing course objectives. Though perhaps tedious in initial development, both faculty and student satisfaction with the clinical evaluation process can be enhanced with the use of rubrics. PMID:19083270

  15. Student nurses experience of learning in the clinical environment.

    PubMed

    Papastavrou, Evridiki; Lambrinou, Ekaterini; Tsangari, Haritini; Saarikoski, Mikko; Leino-Kilpi, Helena

    2010-05-01

    The clinical learning environment is a complex social entity that influences student learning outcomes in the clinical setting. Exploration of this environment gives insight into the educational functioning of the clinical areas and allows nurse teachers to enhance students' opportunities for learning. Since Cyprus is undergoing major reforms in nursing education, building on the experience and knowledge gained, this study aims to explore the present clinical situation and how this would impact on nursing education moves to the university. As nursing education would take on a different approach, it is assumed the learning approach would also be different, and so utilization of the clinical environment would also be improved. Six hundred and forty five students participated in the study. Data were collected by means of the clinical learning environment and supervision instrument. A statistically significant correlation was found between the sub-dimensions "premises of nursing care" and "premises of learning" indicating that students are relating learning environment with the quality of nursing care and patient relationships. The ward atmosphere and the leadership style of the manager were rated as less important factors for learning. The majority of students experienced a group supervision model, but the more satisfied students were those with a "personal mentor" that was considered as the most successful mentor relationship. The findings suggest more thorough examination and understanding of the characteristics of the clinical environment that are conductive to learning. PMID:19700368

  16. Hot particle dosimetry and radiobiology--past and present.

    PubMed

    Charles, M W; Harrison, J D

    2007-09-01

    Small high-activity radioactive particles of nominal diameter ranging from approximately 1 mm down to several microm have been a radiological concern over the last 30 years in and around European and American nuclear reactor facilities. These particles have often been referred to as 'hot particles'. The 'hot particle problem' came into prominent concern in the late 1960s. The potential carcinogenic effects in lungs as the result of irradiation by discrete small particles containing alpha-emitting radionuclides, particularly (239)Pu, were claimed by some to be several orders of magnitude greater than those produced by uniform irradiation to the same mean dose. The phrase 'hot particle problem' was subsequently used to refer to the difficulty of predicting health effects for all microscopic radioactive sources. The difficulty arose because of the paucity of comparative human, animal or cell studies using radioactive particles, and the lack of validated measurement or calculational techniques for dose estimation for non-uniform exposures. Experience was largely restricted to uniform, large-area/volume exposures. The concern regarding cancer induction was extended to deterministic effects when the ICRP in 1977 failed to give adequate dose limits for dealing with 'hot particle' exposures of the skin. Since 1980, considerable efforts have been made to clarify and solve the dosimetric and radiobiological issues related to the health effects of 'hot particle' exposures. The general recommendations of the ICRP in 1991 used the latest radiobiological data to provide skin dose limits which are applicable to 'hot particle' exposures. More recently the NCRP has extended considerations to other organs. This progress is reviewed and applied to the specific case of the recent evaluation of potential health effects of Dounreay fuel fragments commissioned by the Scottish Environment Protection Agency (SEPA). Analyses of possible doses and risks in this case indicate that the

  17. Three-Dimensional Radiobiologic Dosimetry: Application of Radiobiologic Modeling to Patient-Specific 3-Dimensional Imaging–Based Internal Dosimetry

    PubMed Central

    Prideaux, Andrew R.; Song, Hong; Hobbs, Robert F.; He, Bin; Frey, Eric C.; Ladenson, Paul W.; Wahl, Richard L.; Sgouros, George

    2010-01-01

    Phantom-based and patient-specific imaging-based dosimetry methodologies have traditionally yielded mean organ-absorbed doses or spatial dose distributions over tumors and normal organs. In this work, radiobiologic modeling is introduced to convert the spatial distribution of absorbed dose into biologically effective dose and equivalent uniform dose parameters. The methodology is illustrated using data from a thyroid cancer patient treated with radioiodine. Methods Three registered SPECT/CT scans were used to generate 3-dimensional images of radionuclide kinetics (clearance rate) and cumulated activity. The cumulated activity image and corresponding CT scan were provided as input into an EGSnrc-based Monte Carlo calculation: The cumulated activity image was used to define the distribution of decays, and an attenuation image derived from CT was used to define the corresponding spatial tissue density and composition distribution. The rate images were used to convert the spatial absorbed dose distribution to a biologically effective dose distribution, which was then used to estimate a single equivalent uniform dose for segmented volumes of interest. Equivalent uniform dose was also calculated from the absorbed dose distribution directly. Results We validate the method using simple models; compare the dose-volume histogram with a previously analyzed clinical case; and give the mean absorbed dose, mean biologically effective dose, and equivalent uniform dose for an illustrative case of a pediatric thyroid cancer patient with diffuse lung metastases. The mean absorbed dose, mean biologically effective dose, and equivalent uniform dose for the tumor were 57.7, 58.5, and 25.0 Gy, respectively. Corresponding values for normal lung tissue were 9.5, 9.8, and 8.3 Gy, respectively. Conclusion The analysis demonstrates the impact of radiobiologic modeling on response prediction. The 57% reduction in the equivalent dose value for the tumor reflects a high level of dose

  18. Nursing preceptors' experiences of two clinical education models.

    PubMed

    Mamhidir, Anna-Greta; Kristofferzon, Marja-Leena; Hellström-Hyson, Eva; Persson, Elisabeth; Mårtensson, Gunilla

    2014-08-01

    Preceptors play an important role in the process of developing students' knowledge and skills. There is an ongoing search for the best learning and teaching models in clinical education. Little is known about preceptors' perspectives on different models. The aim of the study was to describe nursing preceptors' experiences of two clinical models of clinical education: peer learning and traditional supervision. A descriptive design and qualitative approach was used. Eighteen preceptors from surgical and medical departments at two hospitals were interviewed, ten representing peer learning (student work in pairs) and eight traditional supervision (one student follows a nurse during a shift). The findings showed that preceptors using peer learning created room for students to assume responsibility for their own learning, challenged students' knowledge by refraining from stepping in and encouraged critical thinking. Using traditional supervision, the preceptors' individual ambitions influenced the preceptorship and their own knowledge was empathized as being important to impart. They demonstrated, observed and gradually relinquished responsibility to the students. The choice of clinical education model is important. Peer learning seemed to create learning environments that integrate clinical and academic skills. Investigation of pedagogical models in clinical education should be of major concern to managers and preceptors. PMID:24512652

  19. Clinical Diagnostic Clues in Crohn's Disease: A 41-Year Experience

    PubMed Central

    Quintana, C.; Galleguillos, L.; Benavides, E.; Quintana, J. C.; Zúñiga, A.; Duarte, I.; Klaassen, J.; Kolbach, M.; Soto, R. M.; Iacobelli, S.; Álvarez, M.; O'Brien, A.

    2012-01-01

    Determining the diagnosis of Crohn's disease has been highly difficult mainly during the first years of this study carried out at the Pontificia Universidad Catolica (PUC) Clinical Hospital. For instance, it has been frequently confused with Irritable bowel syndrome and sometimes misdiagnosed as ulcerative colitis, infectious colitis or enterocolitis, intestinal lymphoma, or coeliac disease. Consequently, it seems advisable to characterize what the most relevant clinical features are, in order to establish a clear concept of Crohn's disease. This difficulty may still be a problem at other medical centers in developing countries. Thus, sharing this information may contribute to a better understanding of this disease. Based on the clinical experience gained between 1963 and 2004 and reported herein, the main clinical characteristics of the disease are long-lasting day and night abdominal pain, which becomes more intense after eating and diarrhoea, sometimes associated to a mass in the abdomen, anal lesions, and other additional digestive and nondigestive clinical features. Nevertheless, the main aim of this work has been the following: is it possible to make, in an early stage, the diagnosis of Crohn's disease with a high degree of certainty exclusively with clinical data? PMID:23213555

  20. Heavy-ion tumor therapy: Physical and radiobiological benefits

    NASA Astrophysics Data System (ADS)

    Schardt, Dieter; Elsässer, Thilo; Schulz-Ertner, Daniela

    2010-01-01

    High-energy beams of charged nuclear particles (protons and heavier ions) offer significant advantages for the treatment of deep-seated local tumors in comparison to conventional megavolt photon therapy. Their physical depth-dose distribution in tissue is characterized by a small entrance dose and a distinct maximum (Bragg peak) near the end of range with a sharp fall-off at the distal edge. Taking full advantage of the well-defined range and the small lateral beam spread, modern scanning beam systems allow delivery of the dose with millimeter precision. In addition, projectiles heavier than protons such as carbon ions exhibit an enhanced biological effectiveness in the Bragg peak region caused by the dense ionization of individual particle tracks resulting in reduced cellular repair. This makes them particularly attractive for the treatment of radio-resistant tumors localized near organs at risk. While tumor therapy with protons is a well-established treatment modality with more than 60 000 patients treated worldwide, the application of heavy ions is so far restricted to a few facilities only. Nevertheless, results of clinical phase I-II trials provide evidence that carbon-ion radiotherapy might be beneficial in several tumor entities. This article reviews the progress in heavy-ion therapy, including physical and technical developments, radiobiological studies and models, as well as radiooncological studies. As a result of the promising clinical results obtained with carbon-ion beams in the past ten years at the Heavy Ion Medical Accelerator facility (Japan) and in a pilot project at GSI Darmstadt (Germany), the plans for new clinical centers for heavy-ion or combined proton and heavy-ion therapy have recently received a substantial boost.

  1. Heavy-ion tumor therapy: Physical and radiobiological benefits

    SciTech Connect

    Schardt, Dieter; Elsaesser, Thilo; Schulz-Ertner, Daniela

    2010-01-15

    High-energy beams of charged nuclear particles (protons and heavier ions) offer significant advantages for the treatment of deep-seated local tumors in comparison to conventional megavolt photon therapy. Their physical depth-dose distribution in tissue is characterized by a small entrance dose and a distinct maximum (Bragg peak) near the end of range with a sharp fall-off at the distal edge. Taking full advantage of the well-defined range and the small lateral beam spread, modern scanning beam systems allow delivery of the dose with millimeter precision. In addition, projectiles heavier than protons such as carbon ions exhibit an enhanced biological effectiveness in the Bragg peak region caused by the dense ionization of individual particle tracks resulting in reduced cellular repair. This makes them particularly attractive for the treatment of radio-resistant tumors localized near organs at risk. While tumor therapy with protons is a well-established treatment modality with more than 60 000 patients treated worldwide, the application of heavy ions is so far restricted to a few facilities only. Nevertheless, results of clinical phase I-II trials provide evidence that carbon-ion radiotherapy might be beneficial in several tumor entities. This article reviews the progress in heavy-ion therapy, including physical and technical developments, radiobiological studies and models, as well as radiooncological studies. As a result of the promising clinical results obtained with carbon-ion beams in the past ten years at the Heavy Ion Medical Accelerator facility (Japan) and in a pilot project at GSI Darmstadt (Germany), the plans for new clinical centers for heavy-ion or combined proton and heavy-ion therapy have recently received a substantial boost.

  2. The interprofessional clinical experience: interprofessional education in the nursing home.

    PubMed

    Sheppard, Kendra D; Ford, Channing R; Sawyer, Patricia; Foley, Kathleen T; Harada, Caroline N; Brown, Cynthia J; Ritchie, Christine S

    2015-03-01

    The interprofessional clinical experience (ICE) was designed to introduce trainees to the roles of different healthcare professionals, provide an opportunity to participate in an interprofessional team, and familiarize trainees with caring for older adults in the nursing home setting. Healthcare trainees from seven professions (dentistry, medicine, nursing, nutrition, occupational therapy, optometry and social work) participated in ICE. This program consisted of individual patient interviews followed by a team meeting to develop a comprehensive care plan. To evaluate the impact of ICE on attitudinal change, the UCLA Geriatric Attitudes Scale and a post-experience assessment were used. The post-experience assessment evaluated the trainees' perception of potential team members' roles and attitudes about interprofessional team care of the older adult. Attitudes toward interprofessional teamwork and the older adult were generally positive. ICE is a novel program that allows trainees across healthcare professions to experience interprofessional teamwork in the nursing home setting. PMID:25140581

  3. Biophysical and biomathematical adventures in radiobiology

    SciTech Connect

    Scott, B.R.

    1991-01-01

    Highlights of my biophysical and biomathematical adventures in radiobiology is presented. Early adventures involved developing state-vector models'' for specific harmful effects (cell killing, life shortening) of exposure to radiation. More recent adventures led to developing hazard-function models'' for predicting biological effects (e.g., cell killing, mutations, tumor induction) of combined exposure to different toxicants. Hazard-function models were also developed for predicting harm to man from exposure to large radiation doses. Major conclusions derived from the modeling adventures are as follows: (1) synergistic effects of different genotoxic agents should not occur at low doses; (2) for exposure of the lung or bone marrow to large doses of photon radiation, low rates of exposure should be better tolerated than high rates; and (3) for some types of radiation (e.g., alpha particles and fission neutrons), moderate doses delivered at a low rate may be more harmful than the same dose given at a high rate. 53 refs., 7 figs.

  4. Understanding Clinical Expertise: Nurse Education, Experience, and the Hospital Context

    PubMed Central

    McHugh, Matthew D.; Lake, Eileen T.

    2010-01-01

    Clinical nursing expertise is central to quality patient care. Research on factors that contribute to expertise has focused largely on individual nurse characteristics to the exclusion of contextual factors. To address this, we examined effects of hospital contextual factors and individual nurse education and experience on clinical nursing expertise in a cross-sectional analysis of data from 8,611 registered nurses. In a generalized ordered logistic regression analysis, the composition of the hospital staff, particularly the proportion of nurses with at least a bachelor of science in nursing degree, was associated with significantly greater odds of a nurse reporting a more advanced expertise level. Our findings suggest that, controlling for individual characteristics, the hospital context significantly influences clinical nursing expertise. PMID:20645420

  5. Radiobiological Determination of Dose Escalation and Normal Tissue Toxicity in Definitive Chemoradiation Therapy for Esophageal Cancer

    SciTech Connect

    Warren, Samantha; Partridge, Mike; Carrington, Rhys; Hurt, Chris; Crosby, Thomas; Hawkins, Maria A.

    2014-10-01

    Purpose: This study investigated the trade-off in tumor coverage and organ-at-risk sparing when applying dose escalation for concurrent chemoradiation therapy (CRT) of mid-esophageal cancer, using radiobiological modeling to estimate local control and normal tissue toxicity. Methods and Materials: Twenty-one patients with mid-esophageal cancer were selected from the SCOPE1 database (International Standard Randomised Controlled Trials number 47718479), with a mean planning target volume (PTV) of 327 cm{sup 3}. A boost volume, PTV2 (GTV + 0.5 cm margin), was created. Radiobiological modeling of tumor control probability (TCP) estimated the dose required for a clinically significant (+20%) increase in local control as 62.5 Gy/25 fractions. A RapidArc (RA) plan with a simultaneously integrated boost (SIB) to PTV2 (RA{sub 62.5}) was compared to a standard dose plan of 50 Gy/25 fractions (RA{sub 50}). Dose-volume metrics and estimates of normal tissue complication probability (NTCP) for heart and lungs were compared. Results: Clinically acceptable dose escalation was feasible for 16 of 21 patients, with significant gains (>18%) in tumor control from 38.2% (RA{sub 50}) to 56.3% (RA{sub 62.5}), and only a small increase in predicted toxicity: median heart NTCP 4.4% (RA{sub 50}) versus 5.6% (RA{sub 62.5}) P<.001 and median lung NTCP 6.5% (RA{sub 50}) versus 7.5% (RA{sub 62.5}) P<.001. Conclusions: Dose escalation to the GTV to improve local control is possible when overlap between PTV and organ-at-risk (<8% heart volume and <2.5% lung volume overlap for this study) generates only negligible increase in lung or heart toxicity. These predictions from radiobiological modeling should be tested in future clinical trials.

  6. The Tumor Radiobiology of SRS and SBRT: Are More Than the 5 Rs Involved?

    SciTech Connect

    Brown, J. Martin; Carlson, David J.; Brenner, David J.

    2014-02-01

    Stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT), also known as stereotactic ablative radiation therapy (SABR), are rapidly becoming accepted practice for the radiation therapy of certain tumors. Typically, SRS and SBRT involve the delivery of 1 or a few large-dose fractions of 8 to 30 Gy per fraction: a major paradigm shift from radiation therapy practice over the past 90 years, when, with relatively large amounts of normal tissues receiving high doses, the goal was to maximize tumor response for an acceptable level of normal tissue injury. The development of SRS and SBRT have come about because of technologic advances in image guidance and treatment delivery techniques that enable the delivery of large doses to tumors with reduced margins and high gradients outside the target, thereby minimizing doses to surrounding normal tissues. Because the results obtained with SRS and SBRT have been impressive, they have raised the question whether classic radiobiological modeling, and the linear-quadratic (LQ) model, are appropriate for large doses per fraction. In addition to objections to the LQ model, the possibility of additional biological effects resulting from endothelial cell damage, enhanced tumor immunity, or both have been raised to account for the success of SRS and SBRT. In this review, we conclude that the available preclinical and clinical data do not support a need to change the LQ model or to invoke phenomena over and above the classic 5 Rs of radiobiology and radiation therapy, with the likely exception that for some tumors high doses of irradiation may produce enhanced antitumor immunity. Thus, we suggest that for most tumors, the standard radiobiology concepts of the 5 Rs are sufficient to explain the clinical data, and the excellent results obtained from clinical studies are the result of the much larger biologically effective doses that are delivered with SRS and SBRT.

  7. The tumor radiobiology of SRS and SBRT: are more than the 5 Rs involved?

    PubMed

    Brown, J Martin; Carlson, David J; Brenner, David J

    2014-02-01

    Stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT), also known as stereotactic ablative radiation therapy (SABR), are rapidly becoming accepted practice for the radiation therapy of certain tumors. Typically, SRS and SBRT involve the delivery of 1 or a few large-dose fractions of 8 to 30 Gy per fraction: a major paradigm shift from radiation therapy practice over the past 90 years, when, with relatively large amounts of normal tissues receiving high doses, the goal was to maximize tumor response for an acceptable level of normal tissue injury. The development of SRS and SBRT have come about because of technologic advances in image guidance and treatment delivery techniques that enable the delivery of large doses to tumors with reduced margins and high gradients outside the target, thereby minimizing doses to surrounding normal tissues. Because the results obtained with SRS and SBRT have been impressive, they have raised the question whether classic radiobiological modeling, and the linear-quadratic (LQ) model, are appropriate for large doses per fraction. In addition to objections to the LQ model, the possibility of additional biological effects resulting from endothelial cell damage, enhanced tumor immunity, or both have been raised to account for the success of SRS and SBRT. In this review, we conclude that the available preclinical and clinical data do not support a need to change the LQ model or to invoke phenomena over and above the classic 5 Rs of radiobiology and radiation therapy, with the likely exception that for some tumors high doses of irradiation may produce enhanced antitumor immunity. Thus, we suggest that for most tumors, the standard radiobiology concepts of the 5 Rs are sufficient to explain the clinical data, and the excellent results obtained from clinical studies are the result of the much larger biologically effective doses that are delivered with SRS and SBRT. PMID:24411596

  8. Hospice clinical experiences for nursing students: living to the fullest.

    PubMed

    Spicer, Sherri; Heller, Rebecca; Troth, Sarah

    2015-01-01

    Preparing future nurses to provide appropriate care for patients and their families at the end of life can be a formidable challenge for nurse educators. Most nursing schools thread end-of-life concepts throughout the curriculum. Grand Canyon University includes a 40-hour hospice clinical as a component of a home healthcare practicum. Students' weekly written reflections reveal the depth of affective learning that occurs during this experience. Article includes hospice materials and resources. PMID:25585469

  9. Exploring clinical nursing experiences: listening to student nurses.

    PubMed

    Pearcey, Patricia; Draper, Peter

    2008-07-01

    Student nurses spend one half of their educational programme in the clinical area. The success of an educationally sound clinical placement is crucial to forming a professional nursing identity that will encompass the seen and 'unseen' aspects of the nurses' role. The aim of this study was to explore the clinical nursing environment through the perceptions of first year student nurses. Semi-structured interviews were used to collect data from 12 student nurses who each had four weeks clinical experience, representing 21 wards and five hospitals. Results suggest that these student nurses were disillusioned with the reality of clinical nursing and that their expectations of nursing were not realised. They perceived that paperwork, completing tasks and meeting targets were dominant features of nursing work at the expense of patient contact and communication. A majority indicated that nursing was not as caring as they expected and vowed to hold on to their personal values of caring about patients and forming communicative, interpersonal relationships with them. PMID:17950499

  10. Estimation of Radiobiologic Parameters and Equivalent Radiation Dose of Cytotoxic Chemotherapy in Malignant Glioma

    SciTech Connect

    Jones, Bleddyn . E-mail: b.jones.1@bham.ac.uk; Sanghera, Paul

    2007-06-01

    Purpose: To determine the radiobiologic parameters for high-grade gliomas. Methods and Materials: The biologic effective dose concept is used to estimate the {alpha}/{beta} ratio and K (dose equivalent for tumor repopulation/d) for high-grade glioma patients treated in a randomized fractionation trial. The equivalent radiation dose of temozolomide (Temodar) chemotherapy was estimated from another randomized study. The method assumes that the radiotherapy biologic effective dose is proportional to the adjusted radiotherapy survival duration of high-grade glioma patients. Results: The median tumor {alpha}/{beta} and K estimate is 9.32 Gy and 0.23 Gy/d, respectively. Using the published surviving fraction after 2-Gy exposure (SF{sub 2}) data, and the above {alpha}/{beta} ratio, the estimated median {alpha} value was 0.077 Gy{sup -1}, {beta} was 0.009 Gy{sup -2}, and the cellular doubling time was 39.5 days. The median equivalent biologic effective dose of temozolomide was 11.03 Gy{sub 9.3} (equivalent to a radiation dose of 9.1 Gy given in 2-Gy fractions). Random sampling trial simulations based on a cure threshold of 70 Gy in high-grade gliomas have shown the potential increase in tumor cure with dose escalation. Partial elimination of hypoxic cells (by chemical hypoxic cell sensitizers or carbon ion therapy) has suggested that considerable gains in tumor control, which are further supplemented by temozolomide, are achievable. Conclusion: The radiobiologic parameters for human high-grade gliomas can be estimated from clinical trials and could be used to inform future clinical trials, particularly combined modality treatments with newer forms of radiotherapy. Other incurable cancers should be studied using similar radiobiologic analysis.

  11. Clinical experience with adolescent diabetes in a Nigerian teaching hospital.

    PubMed Central

    Akanji, A. O.

    1996-01-01

    Diabetes mellitus presenting in adolescents age 10 to 20 years accounts for less than 5% of all diabetes in tropical African countries. Consequently, inadequate attention is paid to the medical and psychosocial problems attendant on adolescent diabetes in those countries. This article highlights our clinical experience in the management of 30 adolescent diabetic subjects who presented consecutively in the diabetic clinic of a major Nigerian teaching hospital. In these patients, adolescent diabetes appeared heterogeneous, comprising classical insulin-dependent diabetes mellitus (IDDM) in approximately 80%; the remaining fraction (20%) was contributed variably by malnutrition-related diabetes (MRDM) and an "atypical" form of IDDM. The most common medical complications were recurrent hypoglycemia, ketoacidosis, and infections. About 80% of the patients were poor, and up to two thirds had to withdraw from school or trade because of recurrent illness. One third of the girls had a history of unwanted pregnancies. Almost all (93%) had a history of general rebelliousness and clinic truancy. Therefore, the high prevalence of acute metabolic decompensation may be related to the increased frequency of psychosocial problems, especially poverty, in these patients. It is suggested that agencies in tropical Africa increase welfare facilities for adolescent chronic disease, and also establish and encourage clinics dedicated to adolescent diabetes care. PMID:8776066

  12. Developing a leadership pipeline: the Cleveland Clinic experience.

    PubMed

    Hess, Caryl A; Barss, Christina; Stoller, James K

    2014-11-01

    The complexity of health care requires excellent leadership to address the challenges of access, quality, and cost of care. Because competencies to lead differ from clinical or research skills, there is a compelling need to develop leaders and create a talent pipeline, perhaps especially in physician-led organizations like Cleveland Clinic. In this context, we previously reported on a cohort-based physician leadership development course called Leading in Health Care and, in the current report, detail an expanded health care leadership development programme called the Cleveland Clinic Academy (CCA). CCA consists of a broad suite of offerings, including cohort-based learning and 'a la carte' half- or full-day courses addressing specific competencies to manage and to lead. Academy attendance is optional and is available to all physicians, nurses, and administrators with the requisite experience. Course selection is guided by competency matrices which map leadership competencies to specific courses. As of December 2012, a total of 285 course sessions have been offered to 6,050 attendees with uniformly high ratings of course quality and impact. During the past 10 years, Cleveland Clinic's leadership and management curriculum has successfully created a pipeline of health care leaders to fill executive positions, search committees, board openings, and various other organizational leadership positions. Health care leadership can be taught and learned. PMID:25082312

  13. Clinical experience with adolescent diabetes in a Nigerian teaching hospital.

    PubMed

    Akanji, A O

    1996-02-01

    Diabetes mellitus presenting in adolescents age 10 to 20 years accounts for less than 5% of all diabetes in tropical African countries. Consequently, inadequate attention is paid to the medical and psychosocial problems attendant on adolescent diabetes in those countries. This article highlights our clinical experience in the management of 30 adolescent diabetic subjects who presented consecutively in the diabetic clinic of a major Nigerian teaching hospital. In these patients, adolescent diabetes appeared heterogeneous, comprising classical insulin-dependent diabetes mellitus (IDDM) in approximately 80%; the remaining fraction (20%) was contributed variably by malnutrition-related diabetes (MRDM) and an "atypical" form of IDDM. The most common medical complications were recurrent hypoglycemia, ketoacidosis, and infections. About 80% of the patients were poor, and up to two thirds had to withdraw from school or trade because of recurrent illness. One third of the girls had a history of unwanted pregnancies. Almost all (93%) had a history of general rebelliousness and clinic truancy. Therefore, the high prevalence of acute metabolic decompensation may be related to the increased frequency of psychosocial problems, especially poverty, in these patients. It is suggested that agencies in tropical Africa increase welfare facilities for adolescent chronic disease, and also establish and encourage clinics dedicated to adolescent diabetes care. PMID:8776066

  14. Radiobiological evaluation of low dose-rate prostate brachytherapy implants

    NASA Astrophysics Data System (ADS)

    Knaup, Courtney James

    Low dose-rate brachytherapy is a radiation therapy treatment for men with prostate cancer. While this treatment is common, the use of isotopes with varying dosimetric characteristics means that the prescription level and normal organ tolerances vary. Additionally, factors such as prostate edema, seed loss and seed migration may alter the dose distribution within the prostate. The goal of this work is to develop a radiobiological response tool based on spatial dose information which may be used to aid in treatment planning, post-implant evaluation and determination of the effects of prostate edema and seed migration. Aim 1: Evaluation of post-implant prostate edema and its dosimetric and biological effects. Aim 2: Incorporation of biological response to simplify post-implant evaluation. Aim 3: Incorporation of biological response to simplify treatment plan comparison. Aim 4: Radiobiologically based comparison of single and dual-isotope implants. Aim 5: Determine the dosimetric and radiobiological effects of seed disappearance and migration.

  15. Exploring nursing students’ experience of peer learning in clinical practice

    PubMed Central

    Ravanipour, Maryam; Bahreini, Masoud; Ravanipour, Masoumeh

    2015-01-01

    Background: Peer learning is an educational process wherein someone of the same age or level of experience level interacts with other students interested in the same topic. There is limited evidence specifically focusing on the practical use of peer learning in Iran. The aim of this study was to explore nursing students’ experiences of peer learning in clinical practice. Materials and Methods: A qualitative content analysis was conducted. Focus groups were used to find the students’ experiences about peerlearning. Twenty-eight baccalaureate nursing students at Bushehr University of Medical Sciences were selected purposively, and were arranged in four groups of seven students each. The focus group interviews were conducted using a semi-structured interview schedule. All interviews were tape-recorded, transcribed verbatim, and analyzed using conventional content analysis method. Results: The analysis identified four themes: Paradoxical dualism, peer exploitation, first learning efficacy, and socialization practice. Gained advantages and perceived disadvantages created paradoxical dualism, and peer exploitation resulted from peer selection and peer training. Conclusion: Nursing students reported general satisfaction concerning peer learning due to much more in-depth learning with little stress than conventional learning methods. Peer learning is a useful method for nursing students for practicing educational leadership and learning the clinical skills before they get a job. PMID:26097860

  16. Experience of isolated sleep paralysis in clinical practice in Nigeria.

    PubMed

    Ohaeri, J U

    1992-06-01

    The supernatural fears associated with the experience of isolated sleep paralysis in the culture of developing countries is sometimes associated with the evolution of somatic symptoms of psychological origin in patients predisposed to neurotic illness. Patients rarely spontaneously volunteer these fears and doctors pay them scant attention. Illustrative case histories that demonstrate the dynamics of the clinical presentation, as well as the treatment approach, are highlighted. It is hoped that doctors in general medical practice and in psychological medicine in developing countries where belief in supernatural causation of illness is rife will consider these factors in order to provide more effective treatment. PMID:1608064

  17. Experience of isolated sleep paralysis in clinical practice in Nigeria.

    PubMed Central

    Ohaeri, J. U.

    1992-01-01

    The supernatural fears associated with the experience of isolated sleep paralysis in the culture of developing countries is sometimes associated with the evolution of somatic symptoms of psychological origin in patients predisposed to neurotic illness. Patients rarely spontaneously volunteer these fears and doctors pay them scant attention. Illustrative case histories that demonstrate the dynamics of the clinical presentation, as well as the treatment approach, are highlighted. It is hoped that doctors in general medical practice and in psychological medicine in developing countries where belief in supernatural causation of illness is rife will consider these factors in order to provide more effective treatment. PMID:1608064

  18. [Radiobiological aspects of diagnostic X-ray use in dentistry].

    PubMed

    Hoogeveen, R C; van den Aardweg, G J M J

    2015-05-01

    Soon after the discovery of X-rays, it became clear that their use can cause detrimental effects. The field of radiobiology deals with these detrimental effects. In this article, the theoretical concepts of radiobiology relevant to diagnostic X-ray use are presented. The effects of radiation on living tissues, the relationship between dose and effect, and a translation of these effects into the dental application are discussed. X-rays cannot be considered to be harmless even when used at the relatively low doses as in dentistry. If applied with justification and optimization, the risk to the patient will, however, be small. PMID:26210221

  19. A Guide to Professional Excellence in Clinical Experiences in Teacher Education.

    ERIC Educational Resources Information Center

    Smith, Brooks, Ed.; And Others

    This booklet of guidelines for the total program of direct and simulated experiences in teacher education has six major sections: 1) Aims of Clinical Experiences; 2) Guidelines to Excellence with Focusing Questions--40 questions on 12 different aspects of the clinical experience programs; 3) Clinical Experiences: Descriptions and…

  20. [MODIFICATION OF THE PROTON BEAM PHYSICAL PARAMETERS AND RADIOBIOLOGICAL CHARACTERISTICS BY ELEMENTS OF SPACECRAFT RADIATION PROTECTION].

    PubMed

    Ivanov, A A; Molokanov, A G; Shurshakov, V A; Bulynina, T M; Liakhova, K N; Severiukhin, Yu S; Abrosimova, A N; Ushakov, I B

    2015-01-01

    The experiment was performed with outbred ICR (CD-1). female mice (SPF). The animals were irradiated by 171 MeV protons at a dose of 20 cGy. The spacecraft radiation protection elements used in the experiment were a construction of wet hygiene wipes called a "protective blind", and a glass plate imitating an ISS window. Physical obstacles on the path of 171 MeV protons increase their linear energy transfer leading to the absorbed dose elevation and strengthening of the radiobiological effect. In the experiment, two types of obstacles together raised the absorbed dose from 20 to 23.2 cGy. Chemically different materials (glass and water in the wipes) were found to exert unequal modifying effects on physical and biological parameters of the proton-irradiated mice. There was a distinct dose-dependent reduction of bone marrow cellularity within the dose range from 20 cGy to 23.2 cGy in 24 hours after exposure. No modifying effect of the radiation protection elements on spontaneous motor activity was discovered when compared with entrance protons. The group of animals protected by the glass plate exhibited normal orientative-trying reactions and weakened grip with the forelimbs. Rationalization of physical methods of spacecrew protection should be based as on knowledge in physical dosimetry (ionizing chambers, thermoluminescent, track detectors etc.), so the radiobiological criteria established in experiments with animals. PMID:26738306

  1. Clinical trial participants’ experiences of completing questionnaires: a qualitative study

    PubMed Central

    Holmberg, Christine; Karner, Julia J; Rappenecker, Julia; Witt, Claudia M

    2014-01-01

    Objectives To improve clinical study developments for elderly populations, we aim to understand how they transfer their experiences into validated, standardised self-completed study measurement instruments. We analysed how women (mean 78±8 years of age) participating in a randomised controlled trial (RCT) cognised study instruments used to evaluate outcomes of the intervention. Setting The interview study was nested in an RCT on chronic neck pain using common measurement instruments situated in an elderly community in Berlin, Germany, which comprised of units for independent and assisted-living options. Participants The sample (n=20 women) was selected from the RCT sample (n=117, 95% women, mean age 76 (SD±8) years). Interview participants were selected using a purposive sampling list based on the RCT outcomes. Outcomes We asked participants about their experiences completing the RCT questionnaires. Interviews were analysed thematically, then compared with the questionnaires. Results Interviewees had difficulties in translating complex experiences into a single value on a scale and understanding the relationship of the questionnaires to study aims. Interviewees considered important for the trial that their actual experiences were understood by trial organisers. This information was not transferrable by means of the questionnaires. To rectify these difficulties, interviewees used strategies such as adding notes, adding response categories or skipping an item. Conclusions Elderly interview participants understood the importance of completing questionnaires for trial success. This led to strategies of completing the questionnaires that resulted in ‘missing’ or ambiguous data. To improve data collection in elderly populations, educational materials addressing the differential logics should be developed and tested. Pilot testing validated instruments using cognitive interviews may be particularly important in such populations. Finally, when the target of an

  2. Mutuality: clinical and metapsychological potentials of a failed experiment.

    PubMed

    Castillo Mendoza, Carlos Alberto

    2012-03-01

    Ferenczi's experiments with mutual analysis are often dismissed, without acknowledging the results obtained from them and his own cautionary remarks about their limits. Though ultimately failed, Ferenczi's experiments with mutual analysis were a source of clinical and metapsychological knowledge, despite the fact that he was unable to elaborate them in his lifetime. In this paper I connect mutuality to the development of the psyche, especially to the constitutive core of the intrapsychic. To understand the latter, it is necessary to take into account, among others, issues such as the common attribute, the mutual flux between the unconsciouses, the dialogue of unconsciouses, the maternal profundity, the primal relationship with the mother, and, above all, the primal unity between mother and child, which are fundamental for the emergence and development of the primary psychic forces. Incidences of rupture, distortion of the core of mutuality in the psychic life, its loss and disadjustment, by means of external traumatizing forces, and some clinical implications are described. PMID:22398886

  3. Fingolimod Real World Experience: Efficacy and Safety in Clinical Practice

    PubMed Central

    Fonseca, Joaquim

    2015-01-01

    Fingolimod is a multiple sclerosis treatment licensed in Europe since 2011. Its efficacy has been demonstrated in three large phase III trials, used in the regulatory submissions throughout the world. As usual, in these trials the inclusion and exclusion criteria were designed to obtain a homogeneous population, with interchangeable characteristics in the different treatment arms. Although this is the best strategy to achieve a robust answer to the investigation question, it does not guaranty the treatment efficacy in the clinical practice, since in the real world there are concomitant treatments, comorbidities, adherence, and persistence challenges. But, to make informed treatment decision for a real life patient, we need to have evidence of the treatment efficacy, what has been called treatment effectiveness. This work aims to review fingolimod effectiveness, using, as source of information, abstracts, posters, and manuscripts. This unorthodox strategy was developed because more than half of the published experience with fingolimod is still on abstracts and posters. Only a small part of the studies reviewed are already published in peer reviewed journals. Fingolimod seems to be, at least, as effective and safe as it was on clinical trials, and with its long-term experience no new safety signals were observed. PMID:26693475

  4. Clinical experience with flupirtine in the U.S.

    PubMed

    McMahon, F G; Arndt, W F; Newton, J J; Montgomery, P A; Perhach, J L

    1987-01-01

    Flupirtine, a chemically unique, orally effective, non-narcotic, centrally acting analgesic was evaluated for efficacy and safety in five parallel, double-blind randomized clinical trials which included both placebo and active control comparisons. Flupirtine was given in oral doses of 100 to 300 mg, with a maximum daily dose of 600 mg to patients with pain resulting from episiotomy, surgical or dental procedures. Patients rated pain intensity, pain relief and adverse experiences at regular intervals up to 6 hours following medication. Assessments of efficacy included measures of the sum of pain intensity differences (SPID), total pain relief (TOPAR) and peak analgesia (PPID). More than 1300 patients have been evaluated at 26 study sites in the United States. More than 170 of them received flupirtine 100 mg, 250 received 200 mg and 50 received 300 mg. An additional 415 patients received positive control medications (paracetamol 650 mg, codeine 60 mg, pentazocine 50 mg or oxycodone 10 mg plus paracetamol 650 mg). All doses of flupirtine produced analgesia after a single dose. Pharmacokinetic evaluations have shown linear kinetics for flupirtine and a 100 mg t.i.d. dosage schedule produces average steady-state blood levels equivalent to the peak response for a single 200 mg dose. Adverse experiences occurring in flupirtine clinical studies have been minimal in incidence, nature and degree, with drowsiness being the most frequently reported reaction (approximately 10%). PMID:3328854

  5. Trichomycosis (Trichobacteriosis): Clinical and Microbiological Experience with 56 Cases

    PubMed Central

    Bonifaz, Alexandro; Váquez-González, Denisse; Fierro, Leonel; Araiza, Javier; Ponce, Rosa María

    2013-01-01

    Background: Trichomycosis is asymptomatic bacterial infection of the axillary hairs caused by Corynebacterium sp. Objective: to bring a series of cases of trichomycosis, its clinical and microbiological experience. Materials and Methods: This report consists in a linear and observational retrospective study of 15 years of cases of trichomycosis confirmed clinically and microbiologically. Results: Fifty six confirmed cases of trichomycosis were included in this report. The majority were men 53/56 (94.6%), mean age was 32.5 years. The most commonly affected area was the axilla (92%), trichomycosis flava was the principal variant 55/56 (98.2%) and signs and symptoms associated were hyperhidrosis (87.5%), hairs’ texture change (57.1%) and odor (35.7%). Bacterial concretions were observed in all cases, and the predominant causative agent in 89.3% of all cases was Corynebacterium sp. Thirty patients were included in therapeutic portion of the study, and 28 (93.3%) of them experienced a clinical and microbiological cure. Conclusion: Trichomycosis is asymptomatic, superficial infection, which primarily affects axillary hairs. PMID:23960390

  6. A computational tool for patient specific dosimetry and radiobiological modeling of selective internal radiation therapy with (90)Y microspheres.

    PubMed

    Kalantzis, Georgios; Leventouri, Theodora; Apte, Aditiya; Shang, Charles

    2015-11-01

    In recent years we have witnessed tremendous progress in selective internal radiation therapy. In clinical practice, quite often, radionuclide therapy is planned using simple models based on standard activity values or activity administered per unit body weight or surface area in spite of the admission that radiation-dose methods provide more accurate dosimetric results. To address that issue, the authors developed a Matlab-based computational software, named Patient Specific Yttrium-90 Dosimetry Toolkit (PSYDT). PSYDT was designed for patient specific voxel-based dosimetric calculations and radiobiological modeling of selective internal radiation therapy with (90)Y microspheres. The developed toolkit is composed of three dimensional dose calculations for both bremsstrahlung and beta emissions. Subsequently, radiobiological modeling is performed on a per-voxel basis and cumulative dose volume histograms (DVHs) are generated. In this report we describe the functionality and visualization features of PSYDT. PMID:26296058

  7. Almotriptan: a review of 10 years' clinical experience.

    PubMed

    Pascual, Julio; Vila, Carlos; McGown, Caroline C

    2010-10-01

    Almotriptan, a serotonin 5-HT 1B/1D agonist, was developed for the acute treatment of migraine with or without aura and has been available for 10 years. This article evaluates the wealth of experience that has been obtained with almotriptan, including large randomized clinical trials (RCTs) and post-marketing studies that more closely reflect everyday clinical practice. Initial RCTs required patients to take almotriptan when migraine pain was of moderate or severe intensity, and found that 12.5 mg provided optimal outcomes for both pain relief and tolerability. Almotriptan effectively improved 2-h pain-relief, reduced migraine-associated symptoms and demonstrated low recurrence rates. These findings were also shown in patient subgroups, such as adolescents and menstrual migraineurs. A secondary finding in these trials was that patients who took almotriptan early, when the pain was still mild, achieved better outcomes. This prompted the initiation of studies designed to assess the effect of almotriptan in early intervention. Open-label trials reported improvements in pain-free end points (2 h, 24 h), and subsequent RCTs confirmed these findings. Pharmacovigilance data from more than 100 million tablets dispensed worldwide have confirmed that almotriptan is associated with a low occurrence of adverse effects, which, in clinical trials, has been shown to be similar to that observed with placebo. The clinical evidence obtained and comparisons made over a decade of use have demonstrated that almotriptan is one of the more effective and fast-acting triptans available, with a placebo-like tolerability profile. This suggests that almotriptan is an excellent choice for patients requiring specific acute migraine treatment. PMID:20945537

  8. Early experience with tedizolid: clinical efficacy, pharmacodynamics, and resistance.

    PubMed

    Rybak, Jeffrey M; Marx, Kayleigh; Martin, Craig A

    2014-11-01

    Antimicrobial resistance among gram-positive organisms such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) continues to limit therapeutic options. The oxazolidinones are a synthetic class of agents now commonly relied on for the treatment of serious MRSA and VRE infections. With increasing utilization of linezolid, resistant pathogens have once again begun to emerge. Tedizolid, a next-generation oxazolidinone, possesses a spectrum of activity including MRSA and VRE, with significantly enhanced potency also against linezolid-resistant strains. Preclinical and early clinical studies have reported positive results, demonstrating a favorable pharmacokinetic profile in combination with key potential safety advantages. In two phase III clinical trials, tedizolid was found noninferior to linezolid in the treatment of acute bacterial skin and skin structure infections. Investigations for treatment of ventilator-acquired and health care-associated pneumonia are currently underway. Tedizolid has been subjected to pharmacodynamics studies throughout its development that have highlighted properties unique to this agent. Considerable accumulations in epithelial lining fluid and antimicrobial activity greatly augmented by the presence of granulocytes suggest that slow but bactericidal activity may be possible in some clinical scenarios. Structural distinctions between tedizolid and linezolid suggest that tedizolid has decreased vulnerability to oxazolidinone resistance mechanisms. Tedizolid minimum inhibitory concentrations are essentially unchanged in organisms possessing the chloramphenicol-florfenicol resistance gene, a horizontally transferable linezolid resistance mechanism. Although the clinical experience with tedizolid remains limited, early data suggest a potential role in the treatment of serious infections due to multidrug-resistant gram-positive pathogens. PMID:25266820

  9. Managing medical images and clinical information: InCor's experience.

    PubMed

    Furuie, Sergio S; Rebelo, Marina S; Moreno, Ramon A; Santos, Marcelo; Bertozzo, Nivaldo; Motta, Gustavo H M B; Pires, Fabio A; Gutierrez, Marco A

    2007-01-01

    Patients usually get medical assistance in several clinics and hospitals during their lifetime, archiving vital information in a dispersed way. Clearly, a proper patient care should take into account that information in order to check for incompatibilities, avoid unnecessary exams, and get relevant clinical history. The Heart Institute (InCor) of São Paulo, Brazil, has been committed to the goal of integrating all exams and clinical information within the institution and other hospitals. Since InCor is one of the six institutes of the University of São Paulo Medical School and each institute has its own information system, exchanging information among the institutes is also a very important aspect that has been considered. In the last few years, a system for transmission, archiving, retrieval, processing, and visualization of medical images integrated with a hospital information system has been successfully created and constitutes the InCor's electronic patient record (EPR). This work describes the experience in the effort to develop a functional and comprehensive EPR, which includes laboratory exams, images (static, dynamic, and three dimensional), clinical reports, documents, and even real-time vital signals. A security policy based on a contextual role-based access control model was implemented to regulate user's access to EPR. Currently, more than 10 TB of digital imaging and communications in medicine (DICOM) images have been stored using the proposed architecture and the EPR stores daily more than 11 GB of integrated data. The proposed storage subsystem allows 6 months of visibility for rapid retrieval and more than two years for automatic retrieval using a jukebox. This paper addresses also a prototype for the integration of distributed and heterogeneous EPR. PMID:17249400

  10. Clinicians’ experiences of becoming a clinical manager: a qualitative study

    PubMed Central

    2012-01-01

    Background There has been an increased interest in recruiting health professionals with a clinical background to management positions in health care. We know little about the factors that influence individuals’ decisions to engage in management. The aim of this study is to explore clinicians’ journeys towards management positions in hospitals, in order to identify potential drivers and barriers to management recruitment and development. Methods We did a qualitative study which included in-depth interviews with 30 clinicians in middle and first-line management positions in Norwegian hospitals. In addition, participant observation was conducted with 20 of the participants. The informants were recruited from medical and surgical departments, and most had professional backgrounds as medical doctors or nurses. Interviews were analyzed by systemic text condensation. Results We found that there were three phases in clinicians’ journey into management; the development of leadership awareness, taking on the manager role and the experience of entering management. Participants’ experiences suggest that there are different journeys into management, in which both external and internal pressure emerged as a recurrent theme. They had not anticipated a career in clinical management, and experienced that they had been persuaded to take the position. Being thrown into the position, without being sufficiently prepared for the task, was a common experience among participants. Being left to themselves, they had to learn management “on the fly”. Some were frustrated in their role due to increasing administrative workloads, without being able to delegate work effectively. Conclusions Path dependency and social pressure seems to influence clinicians’ decisions to enter into management positions. Hospital organizations should formalize pathways into management, in order to identify, attract, and retain the most qualified talents. Top managers should make sure that necessary

  11. Questioning Skills Demonstrated by Approved Clinical Instructors During Clinical Field Experiences

    PubMed Central

    Barnum, Mary G

    2008-01-01

    Context: The current trend in athletic training clinical education places greater emphasis on the quality of interactions occurring between Approved Clinical Instructors (ACIs) and athletic training students (ATSs). Among other attributes, the ability of ACIs to facilitate and direct quality clinical learning experiences may be influenced by the skill with which the ACI is able to use selected teaching strategies. Objective: To gain insight into ACIs' use of questioning as a specific teaching strategy during the clinical education experiences of undergraduate ATSs. Design: Qualitative case study design involving initial and stimulated-recall interviews, prolonged field observations, and audio recording of ACI-ATS interactions. Setting: The primary athletic training facility at one athletic training education program accredited by the Commission on Accreditation of Athletic Training Education. Patients or Other Participants: The 8 ACI participants included 3 full-time athletic training education program faculty members and 5 graduate-level assistants. The 24 ATS participants included 1 senior, 17 juniors, and 6 sophomores. Data Collection and Analysis: Transcribed data collected from 8 initial interviews, 23 field observations, 23 audio-recorded ACI-ATS interactions and 54 stimulated-recall interviews were analyzed through microscopic, open, and axial coding, as well as coding for process. The cognition level of questions posed by ACIs was analyzed according to Sellappah and colleagues' Question Classification Framework. Results: The ACI participants posed 712 questions during the 23 observation periods. Of the total questions, 70.37% were classified as low-level cognitive questions and 17.00% as high-level cognitive questions. The remaining 12.64% were classified as other. Conclusions: Although all ACIs used questioning during clinical instruction, 2 distinct questioning patterns were identified: strategic questioning and nonstrategic questioning. The way ACIs

  12. Tritium radiobiology research in the US DOE program

    SciTech Connect

    Carsten, A.L.

    1986-01-01

    The history of the original US Atomic Energy Commission, its replacement, the Energy Research and Development Administration, and the present Department of Energy's interest and sponsorship of tritium radiobiology is reviewed beginning in 1971 and continuing through 1986. In particular, the four remaining US Department of Energy, Division of Health and Environmental Research programs are described in some detail.

  13. Research in radiobiology. Annual report, Internal Irradiation Program

    SciTech Connect

    Miller, S.C.; Buster, D.S.

    1985-12-31

    The annual progress report for the Radiobiology Division of the University of Utah College of Medicine is presented. Summaries of twenty-four projects concerning the metabolism, dosimetry and toxicity of a variety of actinide elements in beagles or rats are given. Individual papers within this report have been separately indexed and abstracted for the data base.

  14. Issues for Simulation of Galactic Cosmic Ray Exposures for Radiobiological Research at Ground-Based Accelerators

    PubMed Central

    Kim, Myung-Hee Y.; Rusek, Adam; Cucinotta, Francis A.

    2015-01-01

    For radiobiology research on the health risks of galactic cosmic rays (GCR) ground-based accelerators have been used with mono-energetic beams of single high charge, Z and energy, E (HZE) particles. In this paper, we consider the pros and cons of a GCR reference field at a particle accelerator. At the NASA Space Radiation Laboratory (NSRL), we have proposed a GCR simulator, which implements a new rapid switching mode and higher energy beam extraction to 1.5 GeV/u, in order to integrate multiple ions into a single simulation within hours or longer for chronic exposures. After considering the GCR environment and energy limitations of NSRL, we performed extensive simulation studies using the stochastic transport code, GERMcode (GCR Event Risk Model) to define a GCR reference field using 9 HZE particle beam–energy combinations each with a unique absorber thickness to provide fragmentation and 10 or more energies of proton and 4He beams. The reference field is shown to well represent the charge dependence of GCR dose in several energy bins behind shielding compared to a simulated GCR environment. However, a more significant challenge for space radiobiology research is to consider chronic GCR exposure of up to 3 years in relation to simulations with animal models of human risks. We discuss issues in approaches to map important biological time scales in experimental models using ground-based simulation, with extended exposure of up to a few weeks using chronic or fractionation exposures. A kinetics model of HZE particle hit probabilities suggests that experimental simulations of several weeks will be needed to avoid high fluence rate artifacts, which places limitations on the experiments to be performed. Ultimately risk estimates are limited by theoretical understanding, and focus on improving knowledge of mechanisms and development of experimental models to improve this understanding should remain the highest priority for space radiobiology research. PMID:26090339

  15. Issues for Simulation of Galactic Cosmic Ray Exposures for Radiobiological Research at Ground-Based Accelerators.

    PubMed

    Kim, Myung-Hee Y; Rusek, Adam; Cucinotta, Francis A

    2015-01-01

    For radiobiology research on the health risks of galactic cosmic rays (GCR) ground-based accelerators have been used with mono-energetic beams of single high charge, Z and energy, E (HZE) particles. In this paper, we consider the pros and cons of a GCR reference field at a particle accelerator. At the NASA Space Radiation Laboratory (NSRL), we have proposed a GCR simulator, which implements a new rapid switching mode and higher energy beam extraction to 1.5 GeV/u, in order to integrate multiple ions into a single simulation within hours or longer for chronic exposures. After considering the GCR environment and energy limitations of NSRL, we performed extensive simulation studies using the stochastic transport code, GERMcode (GCR Event Risk Model) to define a GCR reference field using 9 HZE particle beam-energy combinations each with a unique absorber thickness to provide fragmentation and 10 or more energies of proton and (4)He beams. The reference field is shown to well represent the charge dependence of GCR dose in several energy bins behind shielding compared to a simulated GCR environment. However, a more significant challenge for space radiobiology research is to consider chronic GCR exposure of up to 3 years in relation to simulations with animal models of human risks. We discuss issues in approaches to map important biological time scales in experimental models using ground-based simulation, with extended exposure of up to a few weeks using chronic or fractionation exposures. A kinetics model of HZE particle hit probabilities suggests that experimental simulations of several weeks will be needed to avoid high fluence rate artifacts, which places limitations on the experiments to be performed. Ultimately risk estimates are limited by theoretical understanding, and focus on improving knowledge of mechanisms and development of experimental models to improve this understanding should remain the highest priority for space radiobiology research. PMID:26090339

  16. The Meta-Analysis of Clinical Judgment Project: Effects of Experience on Judgment Accuracy

    ERIC Educational Resources Information Center

    Spengler, Paul M.; White, Michael J.; Aegisdottir, Stefania; Maugherman, Alan S.; Anderson, Linda A.; Cook, Robert S.; Nichols, Cassandra N.; Lampropoulos, Georgios K.; Walker, Blain S.; Cohen, Genna R.; Rush, Jeffrey D.

    2009-01-01

    Clinical and educational experience is one of the most commonly studied variables in clinical judgment research. Contrary to clinicians' perceptions, clinical judgment researchers have generally concluded that accuracy does not improve with increased education, training, or clinical experience. In this meta-analysis, the authors synthesized…

  17. Junior nursing students' experiences of vertical violence during clinical rotations.

    PubMed

    Thomas, Sandra P; Burk, Renee

    2009-01-01

    Horizontal violence is a form of workplace violence, a phenomenon that is prevalent in the nursing profession. Research has revealed a variety of negative peer-to-peer behaviors that lower morale and lead to turnover. However, little research has been conducted on "eating our young" (violence occurring between individuals with unequal power, such as staff nurse and student). We propose "vertical violence" as the appropriate term when abusive registered nurse (RN) behavior is directed towards students. We report a content analysis of stories written by junior nursing students about incidents of injustice perpetrated by staff RNs during their clinical experiences. Four levels of injustice were described. Nursing leadership, both in hospitals and educational institutions, must become engaged in efforts to eradicate vertical violence towards students. PMID:19631065

  18. Clinical experience with a recombinant DNA hepatitis B vaccine.

    PubMed

    Andre, F E

    1988-09-01

    The clinical testing of EngerixR-B, the hepatitis B vaccine produced by SmithKline Biologicals using recombinant DNA technology, started in February 1984. Since extensive pre-clinical laboratory work had established that the polypeptide (HBsAg) expressed in genetically engineered yeast cells was after purification--physically, chemically and antigenically similar to the viral surface antigen particles found in the blood of chronic carriers, the aims of the clinical trials were to compare the safety, reactogenicity, immunogenicity and protective efficacy of yeast-derived (YDV) and plasma-derived (PDV) vaccines. By September 1987, 89 studies had been initiated involving a total of 10,545 subjects aged from birth to 82 years. This extensive experience has established that the risk of hypersensitivity to yeast-derived contaminants is negligible since no hypersensitivity reaction has been observed in any vaccinee, the incidence and severity of local reactions have not increased after repeated inoculations and no anti-yeast antibodies were produced by vaccination. Reactogenicity has been comparable to that of PDV's consisting essentially of transient mild irritation at the site of injection presumably caused by the aluminium hydroxide used as adjuvant. The anti-HBs responses to YDV and PDV's were quantitatively (seroconversion rates, peak antibody levels and persistence) as well as qualitatively (epitope specificity and affinity) similar. The expected protective effect of the immune response to the vaccine was confirmed in a challenge study in chimpanzees and in vaccinated human populations (male homosexuals, institutionalized mentally retarded patients, neonates of carrier women) with historically a high infection rate. PMID:2464196

  19. Clinical experience of spontaneous pneumomediastinum: diagnosis and treatment

    PubMed Central

    Kim, Kyung Soo; Jeon, Hyun Woo; Moon, Youngkyu; Kim, Young Du; Ahn, Myeong Im; Park, Jae Kil

    2015-01-01

    Background Spontaneous pneumomediastinum (SPM) is a benign disease with a variety degree of severity but definite treatment modality is not clearly identified with its rarity. The purpose of this study was to review our experience and discuss the management of SPM according to the severity of disease. Methods From March 1996 to December 2012, total 64 patients were enrolled and classified as mild, moderate and severe groups and subsequent clinical courses were analyzed retrospectively. Results Fifty-one were males and 13 were females (M:F =3.9:1) with a mean age of 18 years old (range: 10-30 years old). Thirty-six patients were in mild, 22 in moderate and 6 in severe group. Chief complaints were chest pain (50 cases; 78.1%), neck pain (35 cases; 54.7%), dyspnea (18 cases; 28.1%), odynophagia (9 cases; 14.1%) and precipitating factors were coughing in 12 cases, feeding problems in 9 cases, and vomiting in 7 cases; however, 34 patients (53.1%) had no precipitating signs. All patients received oxygen therapy (100%), prophylactic antibiotics in 57 patients (89.1%), and pain medications in 47 patients (73.4%). The mean hospital stay was 4.6 days (range: 1-10 days). There was an increased linear trend according to time to visit (P=0.023) but clinical course demonstrated no significant trend between groups. Conclusions These data demonstrated that there was no difference in symptom, clinical course and SPM was adequately treated with conservative management regardless of the degree of severity of SPM. PMID:26623105

  20. Dasatinib first-line: Multicentric Italian experience outside clinical trials.

    PubMed

    Breccia, Massimo; Stagno, Fabio; Luciano, Luigiana; Abruzzese, Elisabetta; Annunziata, Mario; D'Adda, Mariella; Maggi, Alessandro; Sgherza, Nicola; Russo-Rossi, Antonella; Pregno, Patrizia; Castagnetti, Fausto; Iurlo, Alessandra; Latagliata, Roberto; Cedrone, Michele; Di Renzo, Nicola; Sorà, Federica; Rege-Cambrin, Giovanna; La Nasa, Giorgio; Scortechini, Anna Rita; Greco, Giovanna; Franceschini, Luca; Sica, Simona; Bocchia, Monica; Crugnola, Monica; Orlandi, Esther; Guarini, Attilio; Specchia, Giorgina; Rosti, Gianantonio; Saglio, Giuseppe; Alimena, Giuliana

    2016-01-01

    Dasatinib was approved for the treatment of chronic phase (CP) chronic myeloid leukemia (CML) patients in first line therapy based on the demonstration of efficacy and safety reported in patients enrolled in clinical trials. We describe a multicentric Italian "real-life" experience of dasatinib used as frontline treatment outside clinical trials. One hundred and nine patients (median age 54 years) were treated from January 2012 to December 2013. Increased incidence of high risk patients were detected according to stratification (26% according to Sokal score, 19% according to Euro score and 16% according to EUTOS) when compared to company sponsored studies. Median time from diagnosis to start of dasatinib was 18 days. Ten patients received unscheduled starting dose (6 patients 50mg and 4 patients 80 mg QD), whereas 99 patients started with 100mg QD. At 3 months, 92% of patients achieved a BCR-ABL ratio less than 10%. At 6 months, the rate of CCyR was 91% and the rate of MR3 was 40%, with 8% of the patients reaching MR4.5. Ninety-three patients were evaluable at 12 months: the rate of MR3 was 62%, with MR4.5 being achieved by 19% of the patients. At a median follow-up of 12 months, 27 patients (24.7%) were receiving the drug at reduced dose. Two patients (1.8%) experienced a lymphoid blast crisis and the overall incidence of resistance was 8%. As regards safety, the major side effects recorded were thrombocytopenia, neutropenia and pleural effusions, which occurred in 22%, 10% and 8% of patients, respectively. Present results, achieved in a large cohort of patients treated outside clinical trials, further confirm the efficacy and safety of dasatinib as firstline treatment in CML. PMID:26643920

  1. One Thousand Patients With Primary Myelofibrosis: The Mayo Clinic Experience

    PubMed Central

    Tefferi, Ayalew; Lasho, Terra L.; Jimma, Thitina; Finke, Christy M.; Gangat, Naseema; Vaidya, Rakhee; Begna, Kebede H.; Al-Kali, Aref; Ketterling, Rhett P.; Hanson, Curtis A.; Pardanani, Animesh

    2012-01-01

    Objective To share our decades of experience with primary myelofibrosis and underscore the importance of outcomes research studies in designing clinical trials and interpreting their results. Patients and Methods One thousand consecutive patients with primary myelofibrosis seen at Mayo Clinic between November 4, 1977, and September 1, 2011, were considered. The International Prognostic Scoring System (IPSS), dynamic IPSS (DIPSS), and DIPSS-plus were applied for risk stratification. Separate analyses were included for patients seen at time of referral (N=1000), at initial diagnosis (N=340), and within or after 1 year of diagnosis (N=660). Results To date, 592 deaths and 68 leukemic transformations have been documented. Parameters at initial diagnosis vs time of referral included median age (66 vs 65 years), male sex (61% vs 62%), red cell transfusion need (24% vs 38%), hemoglobin level less than 10 g/dL (38% vs 54%), platelet count less than 100 × 109/L (18% vs 26%), leukocyte count more than 25 × 109/L (13% vs 16%), marked splenomegaly (21% vs 31%), constitutional symptoms (29% vs 34%), and abnormal karyotype (31% vs 41%). Mutational frequencies were 61% for JAK2V617F, 8% for MPLW515, and 4% for IDH1/2. DIPSS-plus risk distributions at time of referral were 10% low, 15% intermediate-1, 37% intermediate-2, and 37% high. The corresponding median survivals were 17.5, 7.8, 3.6, and 1.8 years vs 20.0, 14.3, 5.3, and 1.7 years for patients younger than 60 years of age. Compared with both DIPSS and IPSS, DIPSS-plus showed better discrimination among risk groups. Five-year leukemic transformation rates were 6% and 21% in low- and high-risk patients, respectively. Conclusion The current document should serve as a valuable resource for patients and physicians and provides context for the design and interpretation of clinical trials. PMID:22212965

  2. Medical academia clinical experiences of Ward Round Teaching curriculum

    PubMed Central

    Haghani, Fariba; Arabshahi, Seyed Kamran Soltani; Bigdeli, Shoaleh; Alavi, Mousa; Omid, Athar

    2014-01-01

    Background: Medical students spend most of their time in hospital wards and it is necessary to study clinical educational opportunities. This study was aimed to explore faculty members’ experience on Ward Round Teaching content. Methods and Materials: This qualitative study was conducted by purposive sampling with the maximum variation of major clinical departments faculty members in Isfahan University of Medical Sciences (n = 9). Data gathering was based on deep and semi-structured interviews. Data gathering continued till data saturation. Data was analyzed through the Collaizzi method and validated. Strategies to ensure trustworthiness of data (credibility, dependability, conformability, transferability) were employed (Guba and Lincoln). Results: Basic codes extracted from the analyzed data were categorized into two main themes and related subthemes, including (1) tangible teachings (analytic intelligence, technical intelligence, legal duties) and (2) implied teachings (professionalism, professional discipline, professional difficulties). Conclusion: Ward round teaching is a valuable opportunity for learners to learn not only patient care aspects but also ethical values. By appropriate planning, opportunities can be used to teach capabilities that are expected of general practitioners. PMID:24627858

  3. Clinical experience of medical students at university sains malaysia.

    PubMed

    Quah, B S; Malik, A S; Simpson, H

    2000-01-01

    Experience of acute medical, surgical conditions, and clinical procedures of undergraduate students were assessed via a questionnaire survey during the final week of the 1993/1998 programme at the School of Medical Sciences, Univestiti Sains Malaysia. Individual performances were assessed by a scoring system. One hundred and twenty four students responded, (response rate 97%). More than 90% had seen myocardial infarction, cerebrovascular accident, pneumonia, respiratory distress, gastroenteritis, coma, and snake bite. Less than 33% had witnessed acute psychosis, diabetic ketoacidosis, acute hepatic failure, status epilepticus, near drowning, hypertensive encephalopathy, acute haemolysis or child abuse.Acute surgical/obstetrics cases, seen by >90% students, included fracture of long bones, head injury, acute abdominal pain, malpresentation and foetal distress. Less than 33% had observed epistaxis, sudden loss of vision, peritonitis or burns. Among operations only herniorrhaphy, Caesarian section, internal fixation of fracture and cataract extraction were seen by >80% students. The main deficits in clinical procedures are in rectal and vaginal examinations, urine collection and microscopic examinations. The performance of individual students, assessed by a scoring system, showed 15 students had unacceptably low scores (<149/230, 50%), 37 had good scores (>181.4/230, 70%) and 5 had superior scores (197.6/230, 80%). PMID:22844212

  4. A new research program for ground-based space radiobiology in Europe

    NASA Astrophysics Data System (ADS)

    Durante, M.; Kraft, G.; O'Neill, P.; Reitz, G.; Sabatier, L.; Schneider, U.

    Space radiation has been long acknowledged as a potential showstopper for long duration manned interplanetary missions Our knowledge of biological effects of cosmic radiation in deep space is almost exclusively derived from ground-based accelerator experiments with heavy ions in animal or in vitro models In an effort to gain more information on space radiation risk and to develop countermeasures NASA started several years ago a Space Radiation Health Program which is currently supporting biological experiments performed at the Brookhaven National Laboratory Upton NY Accelerator-based radiobiology research in the field of space radiation research is also under way in Russia and Japan The European Space Agency ESA has recently established an ambitious exploration program AURORA and within this program it has been decided to start a space radiation research program Europe has a wide tradition in radiobiology research at accelerators generally focussing on charged-particle cancer therapy This expertise can be adapted to address the issue of space radiation risk To support research in this field in Europe ESA issued in 2005 a call for tender for a preliminary study of investigations on biological effects of space radiation IBER This study will prepare future ESA supported-activities in space radiation research by selecting the best European accelerator facilities to be targeted for cooperation and by drafting a roadmap for future research activities The roadmap will include a prioritisation of research topics and a detailed proposal

  5. Preparatory study of a ground-based space radiobiology program in Europe

    NASA Astrophysics Data System (ADS)

    Durante, M.; Kraft, G.; O'Neill, P.; Reitz, G.; Sabatier, L.; Schneider, U.

    Space radiation has long been acknowledged as a potential showstopper for long duration manned interplanetary missions. Our knowledge of biological effects of cosmic radiation in deep space is almost exclusively derived from ground-based accelerator experiments with heavy ions in animal or in vitro models. In an effort to gain more information on space radiation risk and to develop countermeasures, NASA initiated several years ago a Space Radiation Health Program, which is currently supporting biological experiments performed at the Brookhaven National Laboratory. Accelerator-based radiobiology research in the field of space radiation research is also under way in Russia and Japan. The European Space Agency (ESA) has recently established an ambitious exploration program (AURORA), and within this program it has been decided to include a space radiation research program. Europe has a long tradition in radiobiology research at accelerators, generally focussing on charged-particle cancer therapy. This expertise can be adapted to address the issue of space radiation risk. To support research in this field in Europe, ESA issued a call for tender in 2005 for a preliminary study of investigations on biological effects of space radiation (IBER). This study will provide guidance on future ESA-supported activities in space radiation research by identifying the most appropriate European accelerator facilities to be targeted for cooperation, and by drafting a roadmap for future research activities. The roadmap will include a prioritisation of research topics, and a detailed proposal for experimental campaigns for the following 5 10 years.

  6. How Clinical Instructors Can Enhance the Learning Experience of Physical Therapy Students in an Introductory Clinical Placement

    ERIC Educational Resources Information Center

    Cole, Beverley; Wessel, Jean

    2008-01-01

    Purpose: There is little understanding of how physical therapy students are influenced by clinical instructors (CIs) particularly at the outset of their clinical learning. The purpose of this study was to evaluate physical therapy students' perceptions of their learning experiences during an introductory clinical placement. Methods: Subjects were…

  7. Development of a novel experimental model to investigate radiobiological implications of respiratory motion in advanced radiotherapy

    NASA Astrophysics Data System (ADS)

    Cole, Aidan J.; McGarry, Conor K.; Butterworth, Karl T.; Prise, Kevin M.; O'Sullivan, Joe M.; Hounsell, Alan R.

    2012-11-01

    Respiratory motion introduces complex spatio-temporal variations in the dosimetry of radiotherapy. There is a paucity of literature investigating the radiobiological consequences of intrafraction motion and concerns regarding the impact of movement when applied to cancer cell lines in vitro exist. We have addressed this by developing a novel model which accurately replicates respiratory motion under experimental conditions to allow clinically relevant irradiation of cell lines. A bespoke phantom and motor driven moving platform was adapted to accommodate flasks containing medium and cells in order to replicate respiratory motion using varying frequencies and amplitude settings. To study this effect on cell survival in vitro, dose response curves were determined for human lung cancer cell lines H1299 and H460 exposed to a uniform 6 MV radiation field under moving or stationary conditions. Cell survival curves showed no significant difference between irradiation at different dose points for these cell lines in the presence or absence of motion. These data indicate that motion of unshielded cells in vitro does not affect cell survival in the presence of uniform irradiation. This model provides a novel research platform to investigate the radiobiological consequences of respiratory motion in radiotherapy.

  8. Sequencing of Simulation and Clinic Experiences in an Introductory Pharmacy Practice Experience

    PubMed Central

    Hajjar, Emily; DeSevo Bellottie, Gina

    2015-01-01

    Objective. To examine how the intrasemester sequencing of a simulation component, delivered during an ambulatory care introductory pharmacy practice experience (IPPE), affects student performance on a series of 3 assessments delivered during the second professional (P2) year. Design. At the Jefferson College of Pharmacy (JCP), P2 student pharmacists were randomly assigned to 6 weeks of simulation activities, followed by 6 weeks on site at an ambulatory care clinic or vice versa during either the fall or spring semesters. At the end of each semester, these students completed 3 skills-based assessments: answering a series of drug information (DI) questions; conducting medication adherence counseling; and conducting a medication history. The 2 groups’ raw scores on assessment rubrics were compared. Assessment. During academic years 2011-2012 and 2012-2013, 180 P2 student pharmacists participated in the required ambulatory care IPPE. Ninety experienced simulation first, while the other 90 experienced the clinic first. Students assessed over a 2-year time span performed similarly on each of 3 skills-based assessments, regardless of how simulation experiences were sequenced within the IPPE. Conclusion. The lack of significant difference in student performance suggests that schools of pharmacy may have flexibility with regard to how they choose to incorporate simulation into clinical ambulatory care IPPEs. PMID:26688585

  9. Centralization of a regional clinical microbiology service: The Calgary experience

    PubMed Central

    Church, Deirdre L; Hall, Paula

    1999-01-01

    Diagnostic laboratory services in Alberta have been dramatically restructured over the past five years. In 1994, Alberta Health embarked on an aggressive laboratory restructuring that cut back approximately 30% of the overall monies previously paid to the laboratory service sector in Calgary. A unique service delivery model consolidated all institutional and community-based diagnostic testing in a company called Calgary Laboratory Services (CLS) in late 1996. CLS was formed by a public/private partnership between the Calgary Regional Health Care Authority (CRHA) and MDS-Kasper Laboratories. By virtue of its customer service base and scope of testing, CLS provides comprehensive regional laboratory services to the entire populace. Regional microbiology services within CLS have been successfully consolidated over the past three years into a centralized high volume laboratory (HVL). Because the HVL is not located in a hospital, rapid response laboratories (RRLs) are operated at each acute care site. Although the initial principle behind the proposed test menus for the RRLs was that only procedures requiring a clinical turnaround time of more than 2 h stay on-site, many other principles had to be used to develop and implement an efficient and clinically relevant RRL model for microbiology. From these guiding principles, a detailed assessment of the needs of each institution and extensive networking with user groups, the functions of the microbiology RRLs were established and a detailed implementation plan drawn up. The experience at CLS with regards to restructuring a regional microbiology service is described herein. A post-hoc analysis provides the pros and cons of directing and operating a regionalized microbiology service. PMID:22346397

  10. Past and Future Work on Radiobiology Mega-Studies: A Case Study At Argonne National Laboratory

    SciTech Connect

    Haley, Benjamin; Wang, Qiong; Wanzer, Beau; Vogt, Stefan; Finney, Lydia; Yang, Ping Liu; Paunesku, Tatjana; Woloschak, Gayle

    2011-09-06

    Between 1952 and 1992, more than 200 large radiobiology studies were conducted in research institutes throughout Europe, North America, and Japan to determine the effects of external irradiation and internal emitters on the lifespan and tissue toxicity development in animals. At Argonne National Laboratory, 22 external beam studies were conducted on nearly 700 beagle dogs and 50,000 mice between 1969 and 1992. These studies helped to characterize the effects of neutron and gamma irradiation on lifespan, tumorigenesis, and mutagenesis across a range of doses and dosing patterns. The records and tissues collected at Argonne during that time period have been carefully preserved and redisseminated. Using these archived data, ongoing statistical work has been done and continues to characterize quality of radiation, dose, dose rate, tissue, and gender-specific differences in the radiation responses of exposed animals. The ongoing application of newly-developed molecular biology techniques to the archived tissues has revealed gene-specific mutation rates following exposure to ionizing irradiation. The original and ongoing work with this tissue archive is presented here as a case study of a more general trend in the radiobiology megastudies. These experiments helped form the modern understanding of radiation responses in animals and continue to inform development of new radiation models. Recent archival efforts have facilitated open access to the data and materials produced by these studies, and so a unique opportunity exists to expand this continued research.

  11. Past and Future Work on Radiobiology Mega Studies: A Case Study at Argonne National Laboratory

    PubMed Central

    Haley, Benjamin; Wang, Qiong; Wanzer, Beau; Vogt, Stefan; Finney, Lydia; Yang, Ping Liu; Paunesku, Tatjana; Woloschak, Gayle

    2013-01-01

    Between 1952 and 1992 more than 200 large radiobiology studies were conducted in research institutes throughout Europe, North America and Japan to determine the effects of external irradiation and internal emitters on the life span and tissue toxicity development in animals. At Argonne National Laboratory, 22 external beam studies were conducted on nearly 700 beagle dogs and 50,000 mice between 1969 and 1992. These studies helped to characterize the effects of neutron and gamma irradiation on lifespan, tumorigenesis, and mutagenesis across a range of doses and dosing patterns. The records and tissues collected at Argonne during that time period have been carefully preserved and redisseminated. Using these archived data ongoing statistical work has been done and continues to characterize quality of radiation, dose, dose rate, tissue, and gender specific differences in the radiation responses of exposed animals. The ongoing application of newly developed molecular biology techniques to the archived tissues has revealed gene specific mutation rates following exposure to ionizing irradiation. The original and ongoing work with this tissue archive is presented here as a case study of a more general trend in the radiobiology mega studies. These experiments helped form the modern understanding of radiation responses in animals, and continue to inform development of new radiation models. Recent archival efforts have facilitated open access to the data and materials produced by these studies and so a unique opportunity exists to expand this continued research. PMID:22004930

  12. Students' experiences of learning manual clinical skills through simulation.

    PubMed

    Johannesson, Eva; Silén, Charlotte; Kvist, Joanna; Hult, Håkan

    2013-03-01

    Learning manual skills is a fundamental part of health care education, and motor, sensory and cognitive learning processes are essential aspects of professional development. Simulator training has been shown to enhance factors that facilitate motor and cognitive learning. The present study aimed to investigate the students' experiences and thoughts about their learning through simulation skills training. The study was designed for an educational setting at a clinical skills centre. Ten third-year undergraduate nursing students performed urethral catheterisation, using the virtual reality simulator UrecathVision™, which has haptic properties. The students practised in pairs. Each session was videotaped and the video was used to stimulate recall in subsequent interviews. The interviews were analysed using qualitative content analysis. The analysis from interviews resulted in three themes: what the students learn, how the students learn, and the simulator's contribution to the students' learning. Students learned manual skills, how to perform the procedure, and professional behaviour. They learned by preparing, watching, practising and reflecting. The simulator contributed by providing opportunities for students to prepare for the skills training, to see anatomical structures, to feel resistance, and to become aware of their own performance ability. The findings show that the students related the task to previous experiences, used sensory information, tested themselves and practised techniques in a hands-on fashion, and reflected in and on action. The simulator was seen as a facilitator to learning the manual skills. The study design, with students working in pairs combined with video recording, was found to enhance opportunities for reflection. PMID:22395307

  13. Assessment of radiobiological metrics applied to patient-specific QA process of VMAT prostate treatments.

    PubMed

    Clemente-Gutiérrez, Francisco; Pérez-Vara, Consuelo; Clavo-Herranz, María H; López-Carrizosa, Concepción; Pérez-Regadera, José; Ibáñez-Villoslada, Carmen

    2016-01-01

    VMAT is a powerful technique to deliver hypofractionated prostate treatments. The lack of correlations between usual 2D pretreatment QA results and the clini-cal impact of possible mistakes has allowed the development of 3D verification systems. Dose determination on patient anatomy has provided clinical predictive capability to patient-specific QA process. Dose-volume metrics, as evaluation crite-ria, should be replaced or complemented by radiobiological indices. These metrics can be incorporated into individualized QA extracting the information for response parameters (gEUD, TCP, NTCP) from DVHs. The aim of this study is to assess the role of two 3D verification systems dealing with radiobiological metrics applied to a prostate VMAT QA program. Radiobiological calculations were performed for AAPM TG-166 test cases. Maximum differences were 9.3% for gEUD, -1.3% for TCP, and 5.3% for NTCP calculations. Gamma tests and DVH-based comparisons were carried out for both systems in order to assess their performance in 3D dose determination for prostate treatments (high-, intermediate-, and low-risk, as well as prostate bed patients). Mean gamma passing rates for all structures were bet-ter than 92.0% and 99.1% for both 2%/2 mm and 3%/3 mm criteria. Maximum discrepancies were (2.4% ± 0.8%) and (6.2% ± 1.3%) for targets and normal tis-sues, respectively. Values for gEUD, TCP, and NTCP were extracted from TPS and compared to the results obtained with the two systems. Three models were used for TCP calculations (Poisson, sigmoidal, and Niemierko) and two models for NTCP determinations (LKB and Niemierko). The maximum mean difference for gEUD calculations was (4.7% ± 1.3%); for TCP, the maximum discrepancy was (-2.4% ± 1.1%); and NTCP comparisons led to a maximum deviation of (1.5% ± 0.5%). The potential usefulness of biological metrics in patient-specific QA has been explored. Both systems have been successfully assessed as potential tools for evaluating the clinical

  14. Fournier's Gangrene: A Summary of 10 Years of Clinical Experience

    PubMed Central

    Oguz, Abdullah; Gümüş, Metehan; Turkoglu, Ahmet; Bozdağ, Zübeyir; Ülger, Burak Veli; Agaçayak, Elif; Böyük, Abdullah

    2015-01-01

    We aimed to present our clinical experience with FG treatment. Fournier's gangrene (FG) is a rare but serious disease characterized by progressive necrosis in the genitourinary and perineal region. The retrospective study included 43 patients. Patients were divided into 2 groups as survivors and nonsurvivors. Included in the analysis were data pertaining to demographics, predisposing factors, comorbidities, results of bacteriologic analyses, number of debridements, duration of treatment, FG Severity Index (FGSI) score, fecal diversion methods (trephine ostomy or Flexi-Seal Fecal Management System-FMS), and dressing methods (wet or negative aspiration system). In the nonsurvivor group, urea, WBC, and age were significantly higher, whereas albumin, hematocrit, platelet count, and length of hospital stay (LOHS) were significantly lower compared to the survivor group. Mean FGSI was lower in survivors in comparison with nonsurvivors (5.00 ± 1.86 and 10.00 ± 1.27, respectively; P < 0.001). We conclude that FGSI is an important predictor in the prognosis of FG. Vacuum-assisted closure (VAC) should be performed in compliant patients in order to enhance patient comfort by reducing pain and the number of dressings. Fecal diversion should be performed as needed, preferably by using FMS. The trephine ostomy should be the method of choice in cases where an ostomy is necessary. PMID:25859652

  15. Biological wound dressings sterilized with gamma radiation: Mexican clinical experience

    NASA Astrophysics Data System (ADS)

    Martínez-Pardo, M. E.; Ley-Chávez, E.; Reyes-Frías, M. L.; Rodríguez-Ferreyra, P.; Vázquez-Maya, L.; Salazar, M. A.

    2007-11-01

    Biological wound dressings sterilized with gamma radiation, such as amnion and pig skin, are a reality in Mexico. These tissues are currently processed in the tissue bank and sterilized in the Gamma Industrial Irradiation Plant; both facilities belong to the Instituto Nacional de Investigaciones Nucleares (ININ) (National Institute of Nuclear Research). With the strong support of the International Atomic Energy Agency, the bank was established at the ININ and the Mexican Ministry of Health issued its sanitary license on July 7, 1999. The Quality Management System of the bank was certified by ISO 9001:2000 on August 1, 2003; the scope of the system is "Research, Development and Processing of Biological Tissues Sterilized with Gamma Radiation". At present, more than 150 patients from 16 hospitals have been successfully treated with these tissues. This paper presents a brief description of the tissue processing, as well as the present Mexican clinical experience with children and adult patients who underwent medical treatment with radiosterilized amnion and pig skin, used as biological wound dressings on burns and ocular surface disorders.

  16. Management of laryngeal radionecrosis: Animal and clinical experience

    SciTech Connect

    Oppenheimer, R.W.; Krespi, Y.P.; Einhorn, R.K.

    1989-05-01

    Radiation necrosis of the laryngeal cartilages is an uncommon complication of radiotherapy for laryngeal carcinoma. It is a devastating process for which there is no one acceptable treatment. Medical management offers only temporary, symptomatic relief, which further necessitates surgical treatment. Surgical management may start with a tracheotomy; however, it often ends with a total laryngectomy. Physiologically, the necrotic cartilages are the source of the problem. It is a general surgical principle that nonviable tissue must be excised to promote healing. Therefore, if the affected laryngeal cartilages were removed, the larynx should heal. Total or near total removal of the thyroid and cricoid cartilages with preservation of the endolaryngeal soft tissues has not been reported in the literature. Theoretically, if the entire cartilaginous framework is removed, there would be no structural support for the airway. We have found using animal models, that submucosal resection of the laryngeal cartilages, leaving the perichondrium and endolaryngeal soft tissues intact can result in a competent airway. Animal and clinical experience will be presented.

  17. Normothermic donor heart perfusion: current clinical experience and the future.

    PubMed

    Messer, Simon; Ardehali, Abbas; Tsui, Steven

    2015-06-01

    Following the first successful heart transplant in 1967, more than 100,000 heart transplants have been carried out worldwide. These procedures have mostly relied on cold ischaemic preservation of the donor heart because this simple technique is inexpensive and relatively reliable. However, the well-known limitations of cold ischaemic preservation imposes significant logistical challenges to heart transplantation which put a ceiling on the immediate success on this life-saving therapy, and limits the number of donor hearts that can be safely transplanted annually. Although the theoretical advantages of normothermic donor heart perfusion have been recognised for over a century, the technology to transport donor hearts in this state has only been developed within the last decade. The Organ Care System (OCS) which is designed and manufactured by TransMedics Inc. is currently the only commercially available device with this capability. This article reviews the history of normothermic heart perfusion and the clinical experience with the TransMedics OCS to date. We have also attempted to speculate on the future possibilities of this innovative and exciting technology. PMID:24853906

  18. Radiobiological risk and single event effects during manned space flights.

    PubMed

    Bourrieau, J; Calvet, M C

    1995-01-01

    Radiation hazard during previous manned space flights was not a critical problem as seen from monitoring on board MIR and the SHUTTLE. Future Martian and Lunar missions as well as flights on inclined or high altitude orbits around the Earth can be exposed to a large radiobiological risk and critical reliability losses can be expected, due to Single Event Effects on VLSI devices. The main characteristics of these hazards and some counter-measures to be provided for are given. PMID:11540985

  19. Dosimetry for radiobiological studies of the human hematopoietic system

    NASA Technical Reports Server (NTRS)

    Beck, W. L.; Stokes, T. R.; Lushbaugh, C. C.

    1972-01-01

    A system for estimating individual bone marrow doses in therapeutic radiation exposures of leukemia patients was studied. These measurements are used to make dose response correlations and to study the effect of dose protraction on peripheral blood cell levels. Three irradiators designed to produce a uniform field of high energy gamma radiation for total body exposures of large animals and man are also used for radiobiological studies.

  20. New challenges in high-energy particle radiobiology.

    PubMed

    Durante, M

    2014-03-01

    Densely ionizing radiation has always been a main topic in radiobiology. In fact, α-particles and neutrons are sources of radiation exposure for the general population and workers in nuclear power plants. More recently, high-energy protons and heavy ions attracted a large interest for two applications: hadrontherapy in oncology and space radiation protection in manned space missions. For many years, studies concentrated on measurements of the relative biological effectiveness (RBE) of the energetic particles for different end points, especially cell killing (for radiotherapy) and carcinogenesis (for late effects). Although more recently, it has been shown that densely ionizing radiation elicits signalling pathways quite distinct from those involved in the cell and tissue response to photons. The response of the microenvironment to charged particles is therefore under scrutiny, and both the damage in the target and non-target tissues are relevant. The role of individual susceptibility in therapy and risk is obviously a major topic in radiation research in general, and for ion radiobiology as well. Particle radiobiology is therefore now entering into a new phase, where beyond RBE, the tissue response is considered. These results may open new applications for both cancer therapy and protection in deep space. PMID:24198199

  1. (Radio)Biological Optimization of External-Beam Radiotherapy

    PubMed Central

    Nahum, Alan E.; Uzan, Julien

    2012-01-01

    “Biological optimization” (BIOP) means planning treatments using (radio)biological criteria and models, that is, tumour control probability and normal-tissue complication probability. Four different levels of BIOP are identified: Level I is “isotoxic” individualization of prescription dose Dpresc at fixed fraction number. Dpresc is varied to keep the NTCP of the organ at risk constant. Significant improvements in local control are expected for non-small-cell lung tumours. Level II involves the determination of an individualized isotoxic combination of Dpresc and fractionation scheme. This approach is appropriate for “parallel” OARs (lung, parotids). Examples are given using our BioSuite software. Hypofractionated SABR for early-stage NSCLC is effectively Level-II BIOP. Level-III BIOP uses radiobiological functions as part of the inverse planning of IMRT, for example, maximizing TCP whilst not exceeding a given NTCP. This results in non-uniform target doses. The NTCP model parameters (reflecting tissue “architecture”) drive the optimizer to emphasize different regions of the DVH, for example, penalising high doses for quasi-serial OARs such as rectum. Level-IV BIOP adds functional imaging information, for example, hypoxia or clonogen location, to Level III; examples are given of our prostate “dose painting” protocol, BioProp. The limitations of and uncertainties inherent in the radiobiological models are emphasized. PMID:23251227

  2. New challenges in high-energy particle radiobiology

    PubMed Central

    2014-01-01

    Densely ionizing radiation has always been a main topic in radiobiology. In fact, α-particles and neutrons are sources of radiation exposure for the general population and workers in nuclear power plants. More recently, high-energy protons and heavy ions attracted a large interest for two applications: hadrontherapy in oncology and space radiation protection in manned space missions. For many years, studies concentrated on measurements of the relative biological effectiveness (RBE) of the energetic particles for different end points, especially cell killing (for radiotherapy) and carcinogenesis (for late effects). Although more recently, it has been shown that densely ionizing radiation elicits signalling pathways quite distinct from those involved in the cell and tissue response to photons. The response of the microenvironment to charged particles is therefore under scrutiny, and both the damage in the target and non-target tissues are relevant. The role of individual susceptibility in therapy and risk is obviously a major topic in radiation research in general, and for ion radiobiology as well. Particle radiobiology is therefore now entering into a new phase, where beyond RBE, the tissue response is considered. These results may open new applications for both cancer therapy and protection in deep space. PMID:24198199

  3. Quantitative modeling of chronic myeloid leukemia: insights from radiobiology

    PubMed Central

    Radivoyevitch, Tomas; Hlatky, Lynn; Landaw, Julian

    2012-01-01

    Mathematical models of chronic myeloid leukemia (CML) cell population dynamics are being developed to improve CML understanding and treatment. We review such models in light of relevant findings from radiobiology, emphasizing 3 points. First, the CML models almost all assert that the latency time, from CML initiation to diagnosis, is at most ∼ 10 years. Meanwhile, current radiobiologic estimates, based on Japanese atomic bomb survivor data, indicate a substantially higher maximum, suggesting longer-term relapses and extra resistance mutations. Second, different CML models assume different numbers, between 400 and 106, of normal HSCs. Radiobiologic estimates favor values > 106 for the number of normal cells (often assumed to be the HSCs) that are at risk for a CML-initiating BCR-ABL translocation. Moreover, there is some evidence for an HSC dead-band hypothesis, consistent with HSC numbers being very different across different healthy adults. Third, radiobiologists have found that sporadic (background, age-driven) chromosome translocation incidence increases with age during adulthood. BCR-ABL translocation incidence increasing with age would provide a hitherto underanalyzed contribution to observed background adult-onset CML incidence acceleration with age, and would cast some doubt on stage-number inferences from multistage carcinogenesis models in general. PMID:22353999

  4. Quantitative modeling of chronic myeloid leukemia: insights from radiobiology.

    PubMed

    Radivoyevitch, Tomas; Hlatky, Lynn; Landaw, Julian; Sachs, Rainer K

    2012-05-10

    Mathematical models of chronic myeloid leukemia (CML) cell population dynamics are being developed to improve CML understanding and treatment. We review such models in light of relevant findings from radiobiology, emphasizing 3 points. First, the CML models almost all assert that the latency time, from CML initiation to diagnosis, is at most ∼10 years. Meanwhile, current radiobiologic estimates, based on Japanese atomic bomb survivor data, indicate a substantially higher maximum, suggesting longer-term relapses and extra resistance mutations. Second, different CML models assume different numbers, between 400 and 10(6), of normal HSCs. Radiobiologic estimates favor values>10(6) for the number of normal cells (often assumed to be the HSCs) that are at risk for a CML-initiating BCR-ABL translocation. Moreover, there is some evidence for an HSC dead-band hypothesis, consistent with HSC numbers being very different across different healthy adults. Third, radiobiologists have found that sporadic (background, age-driven) chromosome translocation incidence increases with age during adulthood. BCR-ABL translocation incidence increasing with age would provide a hitherto underanalyzed contribution to observed background adult-onset CML incidence acceleration with age, and would cast some doubt on stage-number inferences from multistage carcinogenesis models in general. PMID:22353999

  5. Modification of radiobiological effects of 171 MeV protons by elements of physical protection

    NASA Astrophysics Data System (ADS)

    Bulinina, Taisia; Shurshakov, Vyacheslav; Ivanov, Alexander; Molokanov, Alexander

    2016-07-01

    Space radiation includes protons of various energies. Physical protection is effective in the case of low energy protons (50-100 MeV) and becomes insufficient for radiation with a high part of high-energy protons. In the experiment performed on outbred mice, the purpose of the study was to evaluate the radiobiological effect of 171 MeV protons and protons modified by elements of physical protection of the spacecraft, on a complex of indicators of the functional condition of the system hematopoiesis and the central nervous system in 24 hours after irradiation at 20 cGy dose. The spacecraft radiation protection elements used in the experiment were a construction of wet hygiene wipes called a «protective curtain», and a glass plate imitating an ISS window. Mass thickness of the " protective curtain" in terms of water equivalent was ̴ 6,2 g/cm2. Physical shielding along the path of 171 MeV protons increases their linear energy transfer leading to the absorbed dose elevation and strengthening of the radiobiological effect. In the experiment, the two types of shielding together raised the absorbed dose from 20 to 23.2 cGy. Chemically different materials (glass and water in the wipes) were found to exert unequal modifying effects on physical and biological parameters of the proton-irradiated mice. There was a distinct dose-dependent reduction of bone marrow cellularity within the dose range from 20 cGy to 23.2 cGy in 24 hours after exposure. No modifying effect of the radiation protection elements on spontaneous motor activity was discovered when compared with entrance protons. The group of animals protected by the glass plate exhibited normal orientative-trying reactions and weakened grip with the forelimbs. The effects observed in the experiment indicate the necessity to carry out comprehensive radiobiological researches (physical, biological and mathematical) in assessing the effects of physical protection, that are actual for ensuring radiation safety of crews in

  6. Treatment plan comparison between helical tomotherapy and MLC-based IMRT using radiobiological measures

    NASA Astrophysics Data System (ADS)

    Mavroidis, Panayiotis; Costa Ferreira, Brigida; Shi, Chengyu; Lind, Bengt K.; Papanikolaou, Nikos

    2007-07-01

    The rapid implementation of advanced treatment planning and delivery technologies for radiation therapy has brought new challenges in evaluating the most effective treatment modality. Intensity-modulated radiotherapy (IMRT) using multi-leaf collimators (MLC) and helical tomotherapy (HT) are becoming popular modes of treatment delivery and their application and effectiveness continues to be investigated. Presently, there are several treatment planning systems (TPS) that can generate and optimize IMRT plans based on user-defined objective functions for the internal target volume (ITV) and organs at risk (OAR). However, the radiobiological parameters of the different tumours and normal tissues are typically not taken into account during dose prescription and optimization of a treatment plan or during plan evaluation. The suitability of a treatment plan is typically decided based on dosimetric criteria such as dose-volume histograms (DVH), maximum, minimum, mean and standard deviation of the dose distribution. For a more comprehensive treatment plan evaluation, the biologically effective uniform dose ({\\bar{\\bar{D}}}) is applied together with the complication-free tumour control probability (P+). Its utilization is demonstrated using three clinical cases that were planned with two different forms of IMRT. In this study, three different cancer types at different anatomical sites were investigated: head and neck, lung and prostate cancers. For each cancer type, a linac MLC-based step-and-shoot IMRT plan and a HT plan were developed. The MLC-based IMRT treatment plans were developed on the Philips treatment-planning platform, using the Pinnacle 7.6 software release. For the tomotherapy HiArt plans, the dedicated tomotherapy treatment planning station was used, running version 2.1.2. By using {\\bar{\\bar{D}}} as the common prescription point of the treatment plans and plotting the tissue response probabilities versus {\\bar{\\bar{D}}} for a range of prescription doses

  7. Clinical Experience With A Portable 3-D Reconstruction Program

    NASA Astrophysics Data System (ADS)

    Holshouser, Barbara A.; Christiansen, Edwin L.; Thompson, Joseph R.; Reynolds, R. Anthony; Goldwasser, Samuel M.

    1988-06-01

    Clinical experience with a computer program for reconstructing and visualizing three-dimensional (3-D) structures is reported. Applications to the study of soft-tissue and skeletal structures, such as the temporomandibular joint and craniofacial anatomy, using computed tomography (CT) data are described. Several features specific to the computer algorithm are demonstrated and evaluated. These include: (1) manipulation of density windows to selectively visualize bone or soft tissue structures; (2) the efficacy of gradient shading algorithms in revealing fine surface detail; and (3) the rapid generation of cut-away views revealing details of internal structures. Also demonstrated is the importance of high resolution data as input to the 3-D program. The implementation of the program (VoxelView-32) described here, is on a MASSCOMP computer running UNIX. Data were collected with General Electric or Siemens CT scanners and transferred to the MASSCOMP for off-line 3-D recon-struction, via magnetic tape or Ethernet. An interactive graphics facility on the MASSCOMP allows viewing of 2-D slices, subregioning, and selection of lower and upper density thresholds for segmentation. The software then enters a pre-processing phase during which a volume representation of the segmented object (soft tissue or bone) is automatically created. This is followed by a rendering phase during which multiple views of the segmented object are automatically generated. The pre-processing phase typically takes 4 to 8 minutes (although very large datasets may require as much as 30 minutes) and the rendering phase typically takes 1 to 2 minutes for each 3-D view. Volume representation and rendering techniques are used at all stages of the processing, and gradient shading is used for enhanced surface detail.

  8. Initial clinical experience using a novel laparoscopy assistant.

    PubMed

    Mishra, Raineesh; Martínez, Arturo Minor; Lorias Espinoza, Daniel

    2011-05-01

    This article presents the first clinical and experimental experiences of the PMASS (Postural Mechatronic Assistance Solo Surgery) from a prospective study carried on on thirteen laparoscopic procedures. Also, their advantages and disadvantages are identified. The PMASS is a system with three articulations; two articulations are passive and one is active; this handles the optic in real time, reducing the latency time by spatial relocation. The surgeons assisted themselves visually in 13 surgical procedures, having direct and intuitive control in real time of the laparoscopic vision field using the PMASS. The surgical and delay time was documented for each surgery. The surgical procedures were: Laparoscopic appendicectomy, ovarian cystectomy and laparoscopic sterilization. In all procedures, surgeons were able to auto-navigate in real time and there was no visual tremor while using the system. The global average times taken to perform the self-assisted surgery with the PMASS for the laparoscopic appendicectomies were 45 ± 4.5 minutes, ovarian cystectomies 49 ± 3.5 minutes and for the laparoscopic sterilization 22 ± 2 minutes. The approximate set-up time of PMASS was one minute, and removal almost a minute (the time required by the surgeon to remove the harness after completing the surgery). The laparoscope itself disengages from the PMASS in a couple of seconds approximately. There were no transoperative or postoperative complications during the procedures. Thirteen laparoscopic procedures were performed, the design of the mechatronic assistance allowed the surgeon to self-assist visually in real time and in an autonomous way in the solo-surgery mode, without compromising the surgical performance and the morbidity. Additionally, the latency times are also reduced by space relocation and coupling of the telescope. PMID:21105849

  9. Chasing Ghosts in Space Radiobiology Research: The Lost Focus on Non-Targeted Effects

    NASA Astrophysics Data System (ADS)

    Cucinotta, Francis; Saganti, Premkumar; Cacao, Eliedonna

    2016-07-01

    The doses and dose-rates of astronaut exposures to galactic cosmic rays (GCR) are accurately known, and lead to particle hits per cell nucleus from high charge and energy (HZE) particles of much less than one hit per cell per week. A large number of experiments have shown that additivity of biological effects is a valid assumption for space radiation exposures, while experiments at higher doses and dose-rates than occur in space continue to be a focus of the majority of space radiobiology research. Furthermore HZE particle exposures with mono-energetic particles manifest themselves as a mixed-radiation field due to the contributions of delta-rays and the random impact parameter of a particles track core to DNA and non-DNA targets in cells and tissues. The mixed-field manifestation of mono-energetic HZE particle exposures is well known from theoretical studies of microdosimetry and track structure. Additional mixed-field effects occur for single species experiments due to nuclear fragmentation in particle accelerator beam-lines and biological samples along with energy straggling. In contrast to these well known aspects of space radiobiology there are many open questions on the contribution of non-targeted effects to low dose and dose-rate exposures. Non-targeted effects (NTEs) include bystander effects and genomic instability, and have been shown to be the most important outstanding question for reducing uncertainties in space radiation cancer risk assessment. The dose-rate and radiation quality dependence of NTE's has not been established, while there is an over-arching need to develop 21st century experimental models of human cancer risk. We review possible mechanisms of NTE's and how new experiments to address these issues could be designed.

  10. A detailed radiobiological and dosimetric analysis of biochemical outcomes in a case-control study of permanent prostate brachytherapy patients

    SciTech Connect

    Butler, Wayne M.; Stewart, Renee R.; Merrick, Gregory S.

    2009-03-15

    the harmonic mean and expressions of the generalized EUD. In this case-control study of prostate brachytherapy biochemical failures and nonfailures, there were no radiobiological parameters derived from detailed DVH-based analysis that predicted for biochemical control. This may indicate that in our approach, implant dosimetry is at or near the limits of clinically effective dose escalation.

  11. Experience with a Family-Practice-Resident-Directed Obstetrical Clinic.

    ERIC Educational Resources Information Center

    Hunter, Jerry L.; Snyder, Frank

    1980-01-01

    At Toledo Hospital, family practice residents have assumed responsibility for the normal obstetrics clinic. Specialty consultations are provided by the hospital's obstetrics residency program. A medical audit of the clinic indicates that the family practice residents obtained consultations and made referrals at the appropriate times. (JMD)

  12. Table Clinics: A Valuable Learning Experience for Allied Health Students.

    ERIC Educational Resources Information Center

    Melton, Jimmie H.

    Table clinics, or short oral presentations on techniques related to some phase of research, diagnosis, or treatment, can be used to enrich allied health education. To present a table clinic, students must choose a topic which lends itself to a 5- to 7-minute presentation and which imparts knowledge that participants can take back to their…

  13. Femtosecond laser eye surgery: the first clinical experience

    NASA Astrophysics Data System (ADS)

    Juhasz, Tibor; Kurtz, Ron M.; Horvath, Christopher; Suarez, Carlos G.; Nordan, Lee; Slade, Steven

    2002-04-01

    A brief review of commercial applications of femtosecond lasers in a clinical setting with emphasis on applications to corneal surgery is presented. The first clinical results of 208 procedures conducted from June to November 2000 is reported. The results show that femtosecond lasers may be safely used as keratome for use in LASIK procedures.

  14. SU-E-T-399: Determination of the Radiobiological Parameters That Describe the Dose-Response Relations of Xerostomia and Disgeusia From Head and Neck Radiotherapy

    SciTech Connect

    Mavroidis, P; Stathakis, S; Papanikolaou, N; Peixoto Xavier, C; Costa Ferreira, B; Khouri, L; Carmo Lopes, M do

    2014-06-01

    Purpose: To estimate the radiobiological parameters that describe the doseresponse relations of xerostomia and disgeusia from head and neck cancer radiotherapy. To identify the organs that are best correlated with the manifestation of those clinical endpoints. Finally, to evaluate the goodnessof- fit by comparing the model predictions against the actual clinical results. Methods: In this study, 349 head and neck cancer patients were included. For each patient the dose volume histograms (DVH) of parotids (separate and combined), mandible, submandibular glands (separate and combined) and salivary glands were calculated. The follow-up of those patients was recorded at different times after the completion of the treatment (7 weeks, 3, 7, 12, 18 and 24 months). Acute and late xerostomia and acute disgeusia were the clinical endpoints examined. A maximum likelihood fitting was performed to calculate the best estimates of the parameters used by the relative seriality model. The statistical methods of the error distribution, the receiver operating characteristic (ROC) curve, the Pearson's test and the Akaike's information criterion were utilized to assess the goodness-of-fit and the agreement between the pattern of the radiobiological predictions with that of the clinical records. Results: The estimated values of the radiobiological parameters of salivary glands are D50 = 25.2 Gy, γ = 0.52, s = 0.001. The statistical analysis confirmed the clinical validity of those parameters (area under the ROC curve = 0.65 and AIC = 38.3). Conclusion: The analysis proved that the treatment outcome pattern of the patient material can be reproduced by the relative seriality model and the estimated radiobiological parameters. Salivary glands were found to have strong volume dependence (low relative seriality). Diminishing the biologically effective uniform dose to salivary glands below 30 Gy may significantly reduce the risk of complications to the patients irradiated for prostate cancer.

  15. Radiobiologic Modeling of Cytoprotection Effects in Radiotherapy

    SciTech Connect

    Plataniotis, George A. . E-mail: gplatan@med.uth.gr; Dale, Roger G.

    2007-05-01

    Purpose: To investigate the potential for mathematical modeling of the normal tissue-sparing effects of cytoprotective agents used in conjunction with radiotherapy and chemotherapy. Methods and Materials: The linear quadratic model was modified to include a 'cytoprotection factor,' in two alternative ways. The published results on the incidence of treatment-related oral mucositis in patients treated for head-and-neck carcinoma using radiotherapy alone or combined with chemotherapy were assessed against the model to determine the likely values of the cytoprotection factor required to confer a reasonable degree of cytoprotection. Results: In both of the model alternatives considered, a cytoprotection factor value of {<=}0.85 was required for a clinically detectable degree of cytoprotection to be realized. A cytoprotection factor value of 0.85 would mean that the radiation sensitivity coefficients would be effectively reduced by 15% on account of the action of the cytoprotector. Conclusion: The incorporation of a cytoprotection factor into an existing linear quadratic method would allow a quantitative assessment of cytoprotection and could be useful in the design of future clinical studies.

  16. Photoacoustic Imaging in Oncology: Translational Preclinical and Early Clinical Experience.

    PubMed

    Valluru, Keerthi S; Wilson, Katheryne E; Willmann, Jürgen K

    2016-08-01

    Photoacoustic imaging has evolved into a clinically translatable platform with the potential to complement existing imaging techniques for the management of cancer, including detection, characterization, prognosis, and treatment monitoring. In photoacoustic imaging, tissue is optically excited to produce ultrasonographic images that represent a spatial map of optical absorption of endogenous constituents such as hemoglobin, fat, melanin, and water or exogenous contrast agents such as dyes and nanoparticles. It can therefore provide functional and molecular information that allows noninvasive soft-tissue characterization. Photoacoustic imaging has matured over the years and is currently being translated into the clinic with various clinical studies underway. In this review, the current state of photoacoustic imaging is presented, including techniques and instrumentation, followed by a discussion of potential clinical applications of this technique for the detection and management of cancer. (©) RSNA, 2016. PMID:27429141

  17. A dedicated undergraduate gynaecology teaching clinic: The Keele experience.

    PubMed

    Katali, Hamza Mahamadu; Parry-Smith, William Rhys; Eliot, Rees L; O'Mahony, Fidelma

    2016-01-01

    Much discussion in the literature centres on how best to teach medical students the intricacies of gynaecological assessment and the subsequent formulation of a management plan. At Keele University skills are initially developed in a simulated setting and then transferred to the workplace where students continue to develop their skills. A dedicated undergraduate gynaecology teaching clinic has been developed and comprises of 2-3 students and a tutor. All 38 students rotating through the department between January and June 2013 were invited to complete an anonymous questionnaire to evaluate this clinic and 36 (95%) of them responded. Respondents felt significantly more comfortable taking a gynaecology history, ensuring privacy during examination and formulating a management plan post-clinic (all p < 0.001), with female students feeling significantly more comfortable than their male counterparts (p = 0.04). The use of this clinic shows great promise to help students learn an unfamiliar and challenging skill. PMID:26492580

  18. Time resolving detector systems for radiobiological investigations of effects of single heavy ions

    SciTech Connect

    Schott, J.U. ||

    1993-12-31

    The combination of the properties of Charge Coupled Devices (CCDs) as image sensor and as detector for energetic charged particles makes them unique for time resolved radiation experiments in which single particles are to be correlated either to their radiation effects in individual objects, or to their sources or origins respectively. The experimental set up for the calibration of a frame transfer CCD type VALVO NXA 1011 with heavy ions from accelerators is described. For low energetic heavy ions, the single particle effects observed in the pixels of the sensor show a fairly linear response with the Linear Energy Transfer (LET) of the particle. As an example for the application of these detector systems in radiobiology, radiation effects of single ionizing particles in the meristem of moving biological objects have been investigated.

  19. Heavy Charged Particle Radiobiology: Using Enhanced Biological Effectiveness and Improved Beam Focusing to Advance Cancer Therapy

    PubMed Central

    Allen, Christopher; Borak, Thomas B.; Tsujii, Hirohiko; Nickoloff, Jac A.

    2011-01-01

    Ionizing radiation causes many types of DNA damage, including base damage and single- and double-strand breaks. Photons, including X-rays and γ-rays, are the most widely used type of ionizing radiation in radiobiology experiments, and in radiation cancer therapy. Charged particles, including protons and carbon ions, are seeing increased use as an alternative therapeutic modality. Although the facilities needed to produce high energy charged particle beams are more costly than photon facilities, particle therapy has shown improved cancer survival rates, reflecting more highly focused dose distributions and more severe DNA damage to tumor cells. Despite early successes of charged particle radiotherapy, there is room for further improvement, and much remains to be learned about normal and cancer cell responses to charged particle radiation. PMID:21376738

  20. Radiobiological studies with the nematode Caenorhabditis elegans. Genetic and developmental effects of high LET radiation

    NASA Technical Reports Server (NTRS)

    Nelson, G. A.; Schubert, W. W.; Marshall, T. M.

    1992-01-01

    The biological effects of heavy charged particle (HZE) radiation are of particular interest to travellers and planners for long-duration space flights where exposure levels represent a potential health hazard. The unique feature of HZE radiation is the structured pattern of its energy deposition in targets. There are many consequences of this feature to biological endpoints when compared with effects of ionizing photons. Dose vs response and dose-rate kinetics may be modified, DNA and cellular repair systems may be altered in their abilities to cope with damage, and the qualitative features of damage may be unique for different ions. The nematode Caenorhabditis elegans is being used to address these and related questions associated with exposure to radiation. HZE-induced mutation, chromosome aberration, cell inactivation and altered organogenesis are discussed along with plans for radiobiological experiments in space.

  1. Heavy charged particle radiobiology: using enhanced biological effectiveness and improved beam focusing to advance cancer therapy.

    PubMed

    Allen, Christopher; Borak, Thomas B; Tsujii, Hirohiko; Nickoloff, Jac A

    2011-06-01

    Ionizing radiation causes many types of DNA damage, including base damage and single- and double-strand breaks. Photons, including X-rays and γ-rays, are the most widely used type of ionizing radiation in radiobiology experiments, and in radiation cancer therapy. Charged particles, including protons and carbon ions, are seeing increased use as an alternative therapeutic modality. Although the facilities needed to produce high energy charged particle beams are more costly than photon facilities, particle therapy has shown improved cancer survival rates, reflecting more highly focused dose distributions and more severe DNA damage to tumor cells. Despite early successes of charged particle radiotherapy, there is room for further improvement, and much remains to be learned about normal and cancer cell responses to charged particle radiation. PMID:21376738

  2. Preclinical and clinical experience with a viscoelastic total disc replacement

    PubMed Central

    Rischke, Burkhard; Ross, Raymond S.; Jollenbeck, Boris A.; Zimmers, Kari B.; Defibaugh, Neal D.

    2011-01-01

    Background The purpose of this study is to describe the mechanical durability and the clinical and radiographic outcomes of a viscoelastic total disc replacement (VTDR). The human intervertebral disc is a complex, viscoelastic structure, permitting and constraining motion in 3 axes, thus providing stability. The ideal disc replacement should be viscoelastic and deformable in all directions, and it should restore disc height and angle. Methods Mechanical testing was conducted to validate the durability of the VTDR, and a clinical study was conducted to evaluate safety and performance. Fifty patients with single-level, symptomatic lumbar degenerative disc disease at L4-5 or L5-S1 were enrolled in a clinical trial at 3 European sites. Patients were assessed clinically and radiographically for 2 years by the Oswestry Disability Index (ODI), a visual analog scale (VAS), and independent radiographic analyses. Results The VTDR showed a fatigue life in excess of 50 million cycles (50-year equivalent) and a physiologically appropriate level of stiffness, motion, geometry, and viscoelasticity. We enrolled 28 men and 22 women in the clinical study, with a mean age of 40 years. Independent quantitative radiographic assessment indicated that the VTDR restored and maintained disc height and lordosis while providing physiologic motion. Mean ODI scores decreased from 48% preoperatively to 23% at 2 years’ follow-up. Mean VAS low-back pain scores decreased from 7.1 cm to 2.9 cm. Median scores indicated that half of the patient population had ODI scores below 10% and VAS low-back pain scores below 0.95 cm at 2 years. Conclusions The VTDR has excellent durability and performs clinically and radiographically as intended for the treatment of symptomatic lumbar degenerative disc disease. Clinical Relevance The VTDR is intended to restore healthy anatomic properties and stability characteristics to the spinal segment. This study is the first to evaluate a VTDR in a 50-patient

  3. Radiobiological speculations on therapeutic total body irradiation

    SciTech Connect

    Vriesendorp, H.M. )

    1990-01-01

    Unexpected total body irradiation (TBI) of human beings, involved in nuclear warfare or in accidents in nuclear reactors can be lethal. In the 1950s, bone marrow transplantation was discovered as a potentially life saving procedure after TBI in the dose range of 5.0 to 12.0 Gy. Since that time, deliberate or therapeutic TBI has been used to condition patients with a lethal bone marrow disorder for bone marrow replacement. The therapeutic ratio of TBI followed by bone marrow transplantation is small. Many potentially lethal complications can occur, such as acute TBI side effects, late TBI side effects or immunological complications of bone marrow transplantation such as graft versus host disease or graft rejection. The benefits of TBI and bone marrow transplantation are that they offer a chance for cure of previously lethal bone marrow disorders. The optimal parameters for TBI remain to be defined. The review discusses the current clinical and experimental animal data, as they relate to the future definition of less toxic TBI procedures with a better therapeutic ratio. Different TBI procedures are required for patients with malignant vs. non-malignant disorders or for patients with histoincompatible vs. histocompatible bone marrow donors.77 references.

  4. Pre-clinical and clinical experiences with novel somatostatin ligands: advantages, disadvantages and new prospects.

    PubMed

    Hofland, L J; van der Hoek, J; Feelders, R; van der Lely, A J; de Herder, W; Lamberts, S W J

    2005-01-01

    Since the cloning and characterization of the five human somatostatin receptor (SSTR) subtypes, our understanding of the expression and functional role of the five SSTR subtypes in human (neuro-)endocrine tumors has increased significantly. The majority of human (neuro-)endocrine tumors express multiple SSTR. GH-secreting pituitary adenomas preferentially express SSTR2 and SSTR5, prolactinomas SSTR1 and SSTR5, and corticotroph adenomas express SSTR2 (low number) and predominantly SSTR5s. In addition, gastroenteropancreatic (GEP) neuroendocrine tumors frequently express multiple SSTR as well, with SSTR2 being expressed at the highest level. Treatment with the current generation of octapeptide somatostatin-analogs, e.g. octreotide and lanreotide, normalizes circulating GH- and IGF-I levels in approximately 60-70% of acromegalic patients, thereby remaining about one-third of patients uncontrolled. In patients with GEP neuroendocrine tumors, both somatostatin-analogs effectively suppress the production of bioactive peptides and hormones by the tumor cells, resulting in an important improvement of the related clinical symptomatology. However, a considerable proportion of patients experience an escape from treatment within months to several years. Altogether, the current generation of somatostatin analogs are effective medical tools in the treatment of acromegalic patients and of patients with neuroendocrine GEP tumors, but there is certainly a need for novel somatostatin analogs. In recent years, a significant number of novel somatostatin-ligands has been developed. These ligands include SSTR selective-, bi-specific, universal, as well as chimeric dopamine (DA)-somatostatin ligands. In vitro studies using human pituitary adenoma cells demonstrate a more profound inhibition of GH, PRL and ACTH secretion by somatostatin-analogs targeting both SSTR2s and SSTR5s, compared with SSTR2-preferential somatostatin-analogs. This likely reflects the SSTR subtype expression pattern

  5. How to Conduct Clinical Qualitative Research on the Patient's Experience

    ERIC Educational Resources Information Center

    Chenail, Ronald J.

    2011-01-01

    From a perspective of patient-centered healthcare, exploring patients' (a) preconceptions, (b) treatment experiences, (c) quality of life, (d) satisfaction, (e) illness understandings, and (f) design are all critical components in improving primary health care and research. Utilizing qualitative approaches to discover patients' experiences can…

  6. An Enzymatic Clinical Chemistry Laboratory Experiment Incorporating an Introduction to Mathematical Method Comparison Techniques

    ERIC Educational Resources Information Center

    Duxbury, Mark

    2004-01-01

    An enzymatic laboratory experiment based on the analysis of serum is described that is suitable for students of clinical chemistry. The experiment incorporates an introduction to mathematical method-comparison techniques in which three different clinical glucose analysis methods are compared using linear regression and Bland-Altman difference…

  7. Evaluating Perceptions of Culminating Clinical Education Experiences of Senior Athletic Training Students

    ERIC Educational Resources Information Center

    Aronson, Patricia A.; Bowman, Thomas G.; Mazerolle, Stephanie M.

    2015-01-01

    Context: The perceptions of athletic training students (ATSs) regarding their clinical education experiences are not fully understood. It is important to investigate ATS perceptions of clinical education to allow athletic training educators to provide educational experiences that will maximize learning. Objective: To determine what ATSs value…

  8. Integrating Clinical Experiences in a TESOL Teacher Education Program: Curriculum Mapping as Process

    ERIC Educational Resources Information Center

    Baecher, Laura

    2012-01-01

    Across all certification areas, teacher education is being challenged to better integrate clinical experiences with coursework. This article describes the process of curriculum mapping and its impact on the organization of clinical experiences in a master's TESOL program over a 1-year redesign process. Although curriculum mapping has been…

  9. Clinical interdisciplinary health team care: an educational experiment.

    PubMed

    Mazur, H; Beeston, J J; Yerxa, E J

    1979-09-01

    With increasing concern for teamwork in clinical practice in health care settings, the need to identify the concepts, methods, and learning processes for improving interdisciplinary team skills is apparent. This paper describes patient-centered, clinical-research-demonstration programs for teams of students, preceptors, and faculty members from six disciplines who provided patient care in a long-term rehabilitation setting. The teams were involved in the theory and practice of team-building, including weekly sessions on leadership styles, communication, group decision-making, and team effectiveness assessment. Objective and subjective measurements were administered throughout the program. The results indicate that task-oriented patient care favors the learning of team skills, especially when all levels of administration support and participate in the processes. Question are raised concerning the effect of clinical teams on the quality of patient care, their cost-effectiveness, and the low priority given to teaching interdisciplinary team skills in professional education. PMID:158089

  10. Clinical Experience of the Klippel-Trenaunay Syndrome

    PubMed Central

    Sung, Hyung Min; Lee, Seok Jong; Lee, Jong Min; Huh, Seung; Lee, Jeong Woo; Choi, Kang Young; Yang, Jung Dug; Cho, Byung Chae

    2015-01-01

    Background The Klippel-Trenaunay syndrome (KTS) is characterized by three clinical features, namely cutaneous capillary malformations, venous malformations, and soft tissue and/or bony hypertrophy of the extremities. The varied manifestations are attributed to the unpredictable clinical nature and prognosis of the syndrome. To elucidate the clinical characteristics of this disease, we reviewed a relatively large number of KTS patients who presented to our vascular anomalies center. Methods We conducted a retrospective study with 19 patients who were diagnosed with KTS and treated in our vascular anomalies clinic between 2003 and 2014, and examined their demographic characteristics, their clinical features, and the treatments administered. Results The sex distribution was balanced, with 9 (47%) males and 10 (53%) females. The mean follow-up period was 4.1 years (range, 7 months-9 years). Most of the patients received conservative treatments such as medication or physiotherapy. Compression therapies such as wearing of elastic garments/bandages were also administered, and surgical interventions were considered only when the patients became excessively symptomatic. Other treatments included laser therapy and sclerotherapy, and all the treatments were adjusted according to each case, tailored to the conditions of the individual patients. Conclusions KTS is an extremely rare, multifactorial disorder that induces widely varied symptoms. Because of this unique feature, plastic surgeons, when not careful, tend to attach a one-sided importance to typical symptoms such as limb hypertrophy or capillary malformation and thus overlook other symptoms and clinical features. KTS can be suspected in all infants who show capillary malformations or limb hypertrophy and require a multi-disciplinary approach for comprehensive management. PMID:26430625

  11. Clinical experience with recombinant molecules for allergy vaccination.

    PubMed

    Cromwell, Oliver; Niederberger, Verena; Horak, Friedrich; Fiebig, Helmut

    2011-01-01

    Numerous allergens have been cloned and produced by the use of recombinant DNA technology. In several cases recombinant variants with reduced IgE-reactivity have also been developed as candidates for allergen specific immunotherapy. Only very few of these proteins have as yet been tested in the clinic, and the major focus has been on birch and grass pollen, two of the most common causes of IgE-mediated allergic disease. This article serves to justify the rational for using recombinant products and reviews the progress that has been made to date with their clinical assessment. PMID:21562972

  12. Necrotizing Craniocervical Soft Tissue Infections: Clinical Experience and Personal Considerations

    PubMed Central

    Lenzi, Riccardo; Castelnuovo, Paolo; Dallan, Iacopo

    2012-01-01

    Necrotizing cervical soft tissue infections (NCSTIs) are devastating uncommon clinical entities that are often life threatening. We report two patients suffering from NCSTI and treated at our institution. Diagnosis of NCSTI has been confirmed histologically and surgically. Both patients were managed with very aggressive treatment (medical and surgical) and survived with minimal morbidity. Early diagnosis and aggressive, multimodality treatment can reduce mortality and morbidity rates. Thoracic and mediastinal involvement requires appropriate management. A strong clinical suspicion remains one of the most important aspects of the management of such shattering conditions. PMID:23304596

  13. Our Experience in a Psychodermatology Liaison Clinic at Manipal, India

    PubMed Central

    Shenoi, Shrutakirthi D; Prabhu, Smitha; Nirmal, B; Petrolwala, Shailee

    2013-01-01

    Psychodermatology is an emerging specialty in dermatology which deals with the interactions between mind and skin. Psychocutaneous diseases can be either primary psychiatric or primary cutaneous, with various degrees of associations between psyche and skin. Unless the dermatologist cultivates a special interest in this field, many an invisible mental disorder may be missed leading to sub optimal treatment of the visible skin condition. Though Dermatology Psychiatry liaison clinics are common in Europe and other western countries, it is just an emerging concept in India. Here we describe the working pattern of psychodermatology liaison clinic established in Manipal in August 2010 and describe briefly the type of cases attended to. PMID:23372214

  14. Differences in Clinical Experiences of ADN and BSN Students.

    ERIC Educational Resources Information Center

    Oermann, Marilyn H.

    1998-01-01

    In a study of 211 associate degree (AD) and 204 baccalaureate nursing students, AD students reported significantly higher stress in clinical practice. Stress for both groups increased as they progressed. Instructors were the predominant source of stress. Students had the most difficulty coping with the demands of patient care and the clinical…

  15. Managing University Clinical Partnership: Learning from International Experience

    ERIC Educational Resources Information Center

    Davies, Stephen; Smith, Tom

    2004-01-01

    Dialogue between the leaders of academic clinical organisations in different countries has revealed that the core elements of the partnership between universities and health care systems are remarkably consistent across national boundaries. There is now an impetus to move beyond analysis of common challenges and towards strategies for success that…

  16. The Clinical/Practicum Experience in Professional Preparation: Preliminary Findings

    ERIC Educational Resources Information Center

    Ralph, Edwin George; Walker, Keith; Wimmer, Randy

    2008-01-01

    The authors synthesize preliminary findings from an interdisciplinary study of the practicum/clinical phase of undergraduate pre-service education in the professions. Early data analysis identified similarities and differences across disciplines in terms of: (a) the terminology describing each practicum program, (b) the programs' key…

  17. Improving biological relevancy of transcriptional biomarkers experiments by applying the MIQE guidelines to pre-clinical and clinical trials.

    PubMed

    Dooms, M; Chango, A; Barbour, E; Pouillart, P; Abdel Nour, A M

    2013-01-01

    The "Minimum Information for the Publication of qPCR Experiments" (MIQE [3]) guidelines are very much targeted at basic research experiments and have to our knowledge not been applied to qPCR assays carried out in the context of clinical trials. This report details the use of the MIQE qPCR app for iPhone (App Store, Apple) to assess the MIQE compliance of one clinical and five pre-clinical trials. This resulted in the need to include 14 modifications that make the guidelines more relevant for the assessment of this special type of application. We also discuss the need for flexibility, since while some parameters increase experimental quality, they also require more reagents and more time, which is not always feasible in a clinical setting. PMID:22910527

  18. Professor Hassan K. Awwad; The Father of Radiation Oncology and Radiobiology in Egypt and the Arab World, His Good Deeds Last Forever and Inspire us for the Future.

    PubMed

    Zaghloul, Mohamed S; El-Badawi, Samy A; Abd Elbaky, Hoda

    2007-03-01

    Our most respected professor Hassan K. Awwad passed away on January 5th, 2007, at the age of 81. He was considered as the father of radiotherapy in Egypt. He was always named "The Professor", as he was the founder of the radiotherapy departments at the National Cancer Institute, Cairo University&Faculty of Medicine, Alexandria University. He also shared in developing NEMROCK (Kasr El Aini Center of Radiation Oncology and Nuclear Medicine), the place where he graduated and worked during his early years of experience. He, together with professor Reda Hamza, dean of NCI, Cairo at that time, had initiated 7 oncology centers all over Egypt, from Aswan in the South to Dammietta and Damanhour in the North. These 7 centers were developed by the Ministry of Health. Prof. Awwad and Prof. Hamza were responsible for facility providing and plans. They chose all the necessary equipment, tools and personnel. These centers were in action since 1988 and are currently taking care of the oncology patients in a wide area of the country. Prof. Awwad graduated from the Faculty of medicine, Cairo University, in 1949. He had his Medical Doctorate (MD) in Radiotherapy from Alexandria University in 1956. The International Atomic Energy Agency (IAEA) awarded him fellowships in France (Institute Gustave Rossy) to gain experience in brachytherapy in 1956 and 1971, England 1956, 1959. Another fellowship was awarded to Prof Awwad in Harvard University (Peter Bent Brigham Hospital) in radiobiology and radiotherapy during the years 1964-1965. He personally and with other members of the National Cancer Institute gave much of their efforts and time to teach, train and guide young radiotherapists, biologists, physicists and radiation therapists through direct on-hand teaching and training as well as holding training courses for radiation oncologists, physicists and technologists. He insisted to ensure its regularity 4 times yearly. These courses trained a lot of personnel from all over Egypt, Sudan

  19. Rapid extraction of DNA from archival clinical specimens: our experiences.

    PubMed

    Poljak, M; Seme, K; Gale, N

    2000-01-01

    The analysis of DNA extracted from archival clinical specimens using polymerase chain reaction represents the basis of a variety of research and diagnostic protocols in medicine. However, the selection of optimal DNA extraction method is critical if such an analysis is to be successful. Recently, we have evaluated a number of rapid DNA extraction protocols in order to find the most suitable method for routine processing of the most common archival materials in pathological and cytological laboratories: paraffin-embedded tissues and Papanicolaou- or Giemsa-stained smears. Our results demonstrate that rapid DNA extraction methods have comparable DNA extraction efficiencies with standard DNA isolation protocols on archival clinical specimens with the exception of Giemsa-stained smears. PMID:10653137

  20. Clinical and experimental experiences of graft-induced dyskinesia.

    PubMed

    Lane, Emma L

    2011-01-01

    Clinical trials evaluating transplantation of fetal tissue for the treatment of Parkinson's disease identified the unexpected side effect of abnormal movements in the 'off'l-DOPA state. Termed graft-induced dyskinesia (GID), various hypotheses have been put forward as to their cause but unfortunately the significant differences in clinical trial protocols and lack of a truly representative animal model has hindered the search for a conclusive basis for their appearance. Likely causative factors have been identified through careful examination of patient data and the use of amphetamine-induced dyskinesia in a rodent model of Parkinson's disease. New trials being planned in Europe hope to avoid GID, whilst maximizing on the functional benefit that can be afforded by this treatment approach but questions still remain as to the underlying mechanism. PMID:21907087

  1. Laboratory and clinical experience with neodymium:YAG laser prostatectomy

    NASA Astrophysics Data System (ADS)

    Kabalin, John N.

    1996-05-01

    Since 1991, we have undertaken extensive laboratory and clinical studies of the Neodymium:YAG (Nd:YAG) laser for surgical treatment of bladder outlet obstruction due to prostatic enlargement or benign prostatic hyperplasia (BPH). Side-firing optical fibers which emit a divergent, relatively low energy density Nd:YAG laser beam produce coagulation necrosis of obstructing periurethral prostate tissue, followed by gradual dissolution and slough in the urinary stream. Laser-tissue interactions and Nd:YAG laser dosimetry for prostatectomy have been studied in canine and human prostate model systems, enhancing clinical application. Ongoing studies examine comparative Nd:YAG laser dosimetry for various beam configurations produced by available side-firing optical fibers and continue to refine operative technique. We have documented clinical outcomes of Nd:YAG laser prostatectomy in 230 consecutive patients treated with the UrolaseTM side-firing optical fiber. Nd:YAG laser coagulation the prostate produces a remarkably low acute morbidity profile, with no significant bleeding or fluid absorption. No postoperative incontinence has been produced. Serial assessments of voiding outcomes over more than 3 years of followup show objective and symptomatic improvement following Nd:YAG laser prostatectomy which is comparable to older but more morbid electrosurgical approaches. Nd:YAG laser prostatectomy is a safe, efficacious, durable and cost-effective treatment for BPH.

  2. Cell irradiation setup and dosimetry for radiobiological studies at ELBE

    NASA Astrophysics Data System (ADS)

    Zeil, K.; Beyreuther, E.; Lessmann, E.; Wagner, W.; Pawelke, J.

    2009-07-01

    The radiation source ELBE delivers different types of secondary radiation, which is used for cell irradiation studies in radiobiological research. Thereby an important issue is the determination of the biological effectiveness of photon radiation as a function of photon energy by using low-energetic, monochromatic channeling radiation (10-100 keV) and high-energetic bremsstrahlung (up to 40 MV). Radiobiological studies at the research facility ELBE demand special technical and dosimetric prerequisites. Therefore, a cell irradiation system (CIS) has been designed, constructed and installed at the beam line. The CIS allows automatic irradiation of a larger cell sample number and the compensation of spatial inhomogeneity of the dose distribution within the beam spot. The recently introduced GafChromic ® EBT radiochromic film model has been used to verify the cell irradiation dose deposition achieving a dose uncertainty of <5%. Both, the installed cell irradiation system and the developed dosimetric procedure based on the use of the EBT film have been experimentally tested at ELBE. The biological effectiveness of 34 MV bremsstrahlung with respect to 200 kV X-rays from a conventional X-ray tube has been determined. An RBE value of 0.75 has been measured in good agreement with literature.

  3. Influence of oxygen on the chemical stage of radiobiological mechanism

    NASA Astrophysics Data System (ADS)

    Barilla, Jiří; Lokajíček, Miloš V.; Pisaková, Hana; Simr, Pavel

    2016-07-01

    The simulation of the chemical stage of radiobiological mechanism may be very helpful in studying the radiobiological effect of ionizing radiation when the water radical clusters formed by the densely ionizing ends of primary or secondary charged particle may form DSBs damaging DNA molecules in living cells. It is possible to study not only the efficiency of individual radicals but also the influence of other species or radiomodifiers (mainly oxygen) being present in water medium during irradiation. The mathematical model based on Continuous Petri nets (proposed by us recently) will be described. It makes it possible to analyze two main processes running at the same time: chemical radical reactions and the diffusion of radical clusters formed during energy transfer. One may study the time change of radical concentrations due to the chemical reactions running during diffusion process. Some orientation results concerning the efficiency of individual radicals in DSB formation (in the case of Co60 radiation) will be presented; the influence of oxygen present in water medium during irradiation will be shown, too.

  4. Suicide Loss Survivors' Experiences with Therapy: Implications for Clinical Practice.

    PubMed

    Sanford, Rebecca; Cerel, Julie; McGann, Vanessa; Maple, Myfanwy

    2016-07-01

    Over two-thirds of suicide loss survivors, those who have lost a loved one to suicide, seek individual therapy following their loss. However, nothing is known about what survivors find helpful about therapy or how therapy impacts their grief. An online survey was conducted June 2012-March 2013 with a convenience sample of 197 survivors primarily from the USA and Australia to develop a better understanding of treatment seeking loss survivors and their experiences in therapy. Questions explored the experience of the suicide death, the therapy received after the loss, and insights about improving therapy for loss survivors. Participants were generally positive about their therapy experiences. However, respondents endorsed symptoms of PTSD, though many did not report a formal diagnosis from a provider, suggesting a discrepancy that could lead to inadequate treatment of symptoms. The findings provide an understanding of treatment seeking loss survivors, along with implications for therapists treating this population. PMID:27074845

  5. Radiobiologic comparison of helical tomotherapy, intensity modulated radiotherapy, and conformal radiotherapy in treating lung cancer accounting for secondary malignancy risks

    SciTech Connect

    Komisopoulos, Georgios; Mavroidis, Panayiotis; Rodriguez, Salvador; Stathakis, Sotirios; Papanikolaou, Nikos; Nikiforidis, Georgios C.; Sakellaropoulos, Georgios C.

    2014-01-01

    The aim of the present study is to examine the importance of using measures to predict the risk of inducing secondary malignancies in association with the clinical effectiveness of treatment plans in terms of tumor control and normal tissue complication probabilities. This is achieved by using radiobiologic parameters and measures, which may provide a closer association between clinical outcome and treatment delivery. Overall, 4 patients having been treated for lung cancer were examined. For each of them, 3 treatment plans were developed based on the helical tomotherapy (HT), multileaf collimator-based intensity modulated radiation therapy (IMRT), and 3-dimensional conformal radiation therapy (CRT) modalities. The different plans were evaluated using the complication-free tumor control probability (p{sub +}), the overall probability of injury (p{sub I}), the overall probability of control/benefit (p{sub B}), and the biologically effective uniform dose (D{sup ¯¯}). These radiobiologic measures were used to develop dose-response curves (p-D{sup ¯¯} diagram), which can help to evaluate different treatment plans when used in conjunction with standard dosimetric criteria. The risks for secondary malignancies in the heart and the contralateral lung were calculated for the 3 radiation modalities based on the corresponding dose-volume histograms (DVHs) of each patient. Regarding the overall evaluation of the different radiation modalities based on the p{sub +} index, the average values of the HT, IMRT, and CRT are 67.3%, 61.2%, and 68.2%, respectively. The corresponding average values of p{sub B} are 75.6%, 70.5%, and 71.0%, respectively, whereas the average values of p{sub I} are 8.3%, 9.3%, and 2.8%, respectively. Among the organs at risk (OARs), lungs show the highest probabilities for complications, which are 7.1%, 8.0%, and 1.3% for the HT, IMRT, and CRT modalities, respectively. Similarly, the biologically effective prescription doses (D{sub B}{sup ¯¯}) for the

  6. Medical students' emotional development in early clinical experience: a model.

    PubMed

    Helmich, Esther; Bolhuis, Sanneke; Laan, Roland; Dornan, Tim; Koopmans, Raymond

    2014-08-01

    Dealing with emotions is a critical feature of professional behaviour. There are no comprehensive theoretical models, however, explaining how medical students learn about emotions. We aimed to explore factors affecting their emotions and how they learn to deal with emotions in themselves and others. During a first-year nursing attachment in hospitals and nursing homes, students wrote daily about their most impressive experiences, explicitly reporting what they felt, thought, and did. In a subsequent interview, they discussed those experiences in greater detail. Following a grounded theory approach, we conducted a constant comparative analysis, collecting and then interpreting data, and allowing the interpretation to inform subsequent data collection. Impressive experiences set up tensions, which gave rise to strong emotions. We identified four 'axes' along which tensions were experienced: 'idealism versus reality', 'critical distance versus adaptation', 'involvement versus detachment' and 'feeling versus displaying'. We found many factors, which influenced how respondents relieved those tensions. Their personal attributes and social relationships both inside and outside the medical community were important ones. Respondents' positions along the different dimensions, as determined by the balance between attributes and tensions, shaped their learning outcomes. Medical students' emotional development occurs through active participation in medical practice and having impressive experiences within relationships with patients and others on wards. Tensions along four dimensions give rise to strong emotions. Gaining insight into the many conditions that influence students' learning about emotions might support educators and supervisors in fostering medical students' emotional and professional development. PMID:23949724

  7. Students' Experiences of Learning Manual Clinical Skills through Simulation

    ERIC Educational Resources Information Center

    Johannesson, Eva; Silen, Charlotte; Kvist, Joanna; Hult, Hakan

    2013-01-01

    Learning manual skills is a fundamental part of health care education, and motor, sensory and cognitive learning processes are essential aspects of professional development. Simulator training has been shown to enhance factors that facilitate motor and cognitive learning. The present study aimed to investigate the students' experiences and…

  8. Co-Learning: Maximizing Learning in Clinical Experiences

    ERIC Educational Resources Information Center

    Merk, Hillary; Waggoner, Jacqueline; Carroll, James

    2013-01-01

    Researchers and teacher educators have given increased attention to co-teaching during the student teaching experience. Co-teaching facilitates an apprenticeship arrangement that encourages modeling of classroom practice for the candidate and a chance to implement directly what is being learned by the apprentice. The co-teaching model can be…

  9. Clinical experience with generic levetiracetam in people with epilepsy

    PubMed Central

    Chaluvadi, Siresha; Chiang, Sharon; Tran, Larry; Goldsmith, Corey E.; Friedman, David E.

    2015-01-01

    SUMMARY Purpose To describe the clinical outcomes of a compulsory switch from branded to generic levetiracetam (LEV) among people with epilepsy (PWE) in an outpatient setting. Methods We conducted a retrospective chart review of 760 unduplicated consecutive adult patients attending a tertiary care epilepsy clinic at Ben Taub General Hospital. On November 1, 2008 hospital policy required all patients receiving branded LEV to be automatically switched to generic LEV. We calculated the proportion of patients switching back to branded LEV and reasons for the switch back. Key Findings Of the 260 patients (34%) being prescribed LEV (generic and brand name) during the study period, 105 (42.9%) were switched back to brand name LEV by their treating physicians. Reasons for switch back included increase in seizure frequency (19.6% vs. 1.6%; p < 0.0001) and adverse effects (AEs) (3.3%). AEs included headache, fatigue, and aggression. Patient age was associated with switchback when controlling for gender, epilepsy classification, and treatment characteristics [relative risk (RR) 2.44; 95% confidence interval (CI) 2.09–2.84; p < 0.05)]. An increase in seizure frequency subsequent to generic substitution was associated with polytherapy compared to monotherapy (3.225; 1.512–6.880; p < 0.05). Significance A significant proportion of patients in our cohort on generic LEV required switch back to the branded drug. Careful monitoring is imperative because a compulsory switch from branded to generic LEV may lead to poor clinical outcomes, with risk of AEs and increased seizure frequency. PMID:21426334

  10. The osmotic tissue expander: a three-year clinical experience.

    PubMed

    Obdeijn, Miryam C; Nicolai, Jean-Philippe A; Werker, Paul M N

    2009-09-01

    Closure of defects after trauma or excision of neoplasms is a basic skill in plastic surgery. Local, regional and distant flaps lead to additional scars. Skin recruitment by serial excision or skin expansion is a less damaging option for defects that must be closed. Advantages of tissue expansion include good colour and texture match. Disadvantages are the need for a second operation, use of an implant with the attendant risk of infection, time needed for inflation of the device, repeat visits to the clinic, and punctures to inflate the expander. To overcome the last disadvantage, an osmotic expander was developed in Germany in 1999 by OSMED GmbH (Ilmenau). PMID:18755643

  11. Application sorption: experience in clinical use and prospects of development.

    PubMed

    Eretskaya, E V; Sakhno, L A; Nikolaev, V G

    1991-01-01

    The analysis of experimental - clinical results obtained during the last decade in the field of application of adsorptive carbon dressings in wound and burn therapy is given. Possible mechanisms of the therapeutic effect of this material are discussed, the feasibility of their application during different phases of wound process and burn disease treatment is demonstrated. The local absorption may be independent efficient method of treatment in the case of surface burns and wound with a small area of injury and provide a pronounced detoxifying effect in the case of suppurative-septic complication of a mechanical trauma and burns. PMID:1751664

  12. Experience of a Clinic for Afghan Refugees in Pakistan

    PubMed Central

    Morgan, Walter A.

    1988-01-01

    Since the Soviets invaded Afghanistan in 1979, 3.5 to 4 million refugees have moved into Pakistan and Iran. Even before the war, the health status of the Afghans was extremely poor and the medical personnel limited. Various international efforts are attempting to cope with the health care needs of the refugees. Economic, language, and cultural problems hamper the projects. One clinic found the most common problems were of the gastrointestinal tract, then the respiratory tract, with a problem ranking similar to that of pre-war Afghanistan. Many of the health problems are linked to deficiencies in sanitation and nutrition. PMID:3247740

  13. Langerhans cell histiocytosis: clinical experience with 124 patients.

    PubMed

    Rivera-Luna, R; Martinez-Guerra, G; Altamirano-Alvarez, E; Martinez-Avalos, A; Cardenas-Cardoz, R; Ayon-Cardenas, A; Ruiz-Maldonado, R; Lopez-Corella, E

    1988-08-01

    We cared for 124 pediatric patients with a histologic diagnosis of Langerhans' cell histiocytosis (histiocytosis X) over a period of 14 years. Clinical, laboratory, and radiographic findings were analyzed. The most frequent manifestations were bone lesions, lymph node involvement, and skin infiltration. Liver disease was noted in 50% of patients and lung disease in 23%; hematologic changes were also frequent. Dysfunction and involvement of these three organ systems, plus age of onset, distinguished the group of patients with the highest mortality. All patients with generalized disease or organ dysfunction were treated with systemic chemotherapy. The actuarial survival curve at 10 years was 63%. PMID:3264610

  14. Use of the NASA Space Radiation Laboratory at Brookhaven National Laboratory to Conduct Charged Particle Radiobiology Studies Relevant to Ion Therapy.

    PubMed

    Held, Kathryn D; Blakely, Eleanor A; Story, Michael D; Lowenstein, Derek I

    2016-06-01

    Although clinical studies with carbon ions have been conducted successfully in Japan and Europe, the limited radiobiological information about charged particles that are heavier than protons remains a significant impediment to exploiting the full potential of particle therapy. There is growing interest in the U.S. to build a cancer treatment facility that utilizes charged particles heavier than protons. Therefore, it is essential that additional radiobiological knowledge be obtained using state-of-the-art technologies and biological models and end points relevant to clinical outcome. Currently, most such ion radiotherapy-related research is being conducted outside the U.S. This article addresses the substantial contributions to that research that are possible at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), which is the only facility in the U.S. at this time where heavy-ion radiobiology research with the ion species and energies of interest for therapy can be done. Here, we briefly discuss the relevant facilities at NSRL and how selected charged particle biology research gaps could be addressed using those facilities. PMID:27195609

  15. Respiratory infections: clinical experiences with the new quinolones.

    PubMed

    Davies, B I; Maesen, F P

    1987-12-11

    Nearly 300 patients, admitted to hospital with acute purulent exacerbations of chronic respiratory disease, have been treated with various newer quinolones: 26 patients received enoxacin, 50 pefloxacin, 80 ciprofloxacin and 143 ofloxacin. Dosages varied from 400 mg once daily to 1000 mg twice daily. orally for five to 10 days. Patients were evaluated bacteriologically and clinically before, during and after treatment. Nearly all infections associated with Haemophilus influenzae and/or Branhamella catarrhalis were successfully eradicated. Some Streptococcus pneumoniae infections relapsed, some could not be eradicated, and a number of patients developed new infections with these organisms. Approximately half of the Pseudomonas aeruginosa infections were eradicated. Nearly all patients received concomitant theophylline but this only caused serious problems in those given 600 mg doses of enoxacin twice daily. Five patients given ciprofloxacin had to discontinue because of unwanted effects (mostly hallucinations), one patient given pefloxacin had gastric pain and two patients given ofloxacin developed a skin rash. Apart from the theophylline interaction, the unwanted effects did not appear to be dose-related. The best overall clinical results were noted after 800 mg doses of ofloxacin once daily for seven days. PMID:3438151

  16. Clinical experiences in fungal keratitis caused by Acremonium

    PubMed Central

    Kim, Seong-Jae; Cho, Yong-Wun; Seo, Seong-Wook; Kim, Sun-Joo; Yoo, Ji-Myong

    2014-01-01

    Purpose To report the predisposing risk factors, clinical presentation, management, and therapeutic outcomes of fungal keratitis caused by Acremonium. Methods This is a retrospective study of cases with Acremonium fungal keratitis that presented to our tertiary referral center between January 2006 and August 2012. Patient demographic and clinical details were determined and reported. Results Five cases of fungal keratitis from Acremonium species were identified in five patients (three males, two females). The mean age of the patients was of 73.4±5.46 years, with a mean follow-up time of 124±72 days. All patients had a history of corneal trauma with vegetable matter. Four cases were unresponsive to initial treatment (0.2% fluconazole, 0.15% amphotericin B) and required topical 5% natamycin, and, in two out of five cases, topical 1% voriconazole. Conclusion The most common risk factors for Acremonium fungal keratitis was ocular trauma. When a corneal lesion is found to be unresponsive to the initial treatment, we should consider adding or substituting topical natamycin or voriconazole for treatment. PMID:24492439

  17. Tc-NGA imaging in liver transplantation: preliminary clinical experience

    SciTech Connect

    Woodle, E.S.; Ward, R.E.; Stadalnik, R.C.; Vera, D.R.

    1989-03-01

    Technetium-99m galactosyl-neoglycoalbumin (Tc-NGA) is a new liver imaging agent that binds to hepatic-binding protein, a hepatocyte-specific membrane receptor. The purpose of this study was to determine the potential of Tc-NGA imaging in clinical liver transplantation. A total of 25 studies were performed in nine patients. Imaging studies performed in the early posttransplant period in patients with good hepatic allograft function revealed diffuse patchiness in tracer distribution, a manifestation of preservation damage. Left lobar infarction was demonstrated within a few hours of ischemic injury. Right posterior segmental infarction was seen in another patient. Comparison of kinetic, clinical, and biochemical data revealed good correlation between hepatic allograft function and Tc-NGA kinetics. Major kinetic alterations were noted during periods of preservation injury, hepatic infarction, and acute rejection. These studies indicate: (1) major alterations in Tc-NGA kinetics occur during preservation injury, hepatic infarction, and acute rejection, and (2) Tc-NGA kinetic data appear to provide an accurate reflection of hepatic allograft function. Tc-NGA imaging has the advantages of being noninvasive and of utilizing standard nuclear medicine instrumentation, including portable imaging devices. In conclusion, Tc-NGA imaging provides a promising noninvasive approach for evaluation of liver function in patients undergoing hepatic transplantation.

  18. Clinical experience of PDT in Brazil: a 300 patient overview

    NASA Astrophysics Data System (ADS)

    Kurachi, Cristina; Ferreira, Juliana; Marcassa, Luis G.; Cestari Filho, Guilherme A.; Souza, Cacilda S.; Bagnato, Vanderlei S.

    2005-04-01

    Clinical application of Photodynamic Therapy (PDT) in Brazil is a result of a pioneering work in a collaborative program involving the Physics Institute and the Medical School of the University of Sao Paulo and the Amaral Carvalho Cancer Hospital in the city of Jau, Sao Paulo. This work began in 1997 with the first patient treated in 1999. Up to the end of 2003 this program has treated over 300 patients and the ones with correct follow up had their lesions included in this report. The majority of the lesions were of non-melanoma skin cancer located on the head and neck region, but the group has also treated Esophagus, Bladder, Gynecological, chest wall recurrence of breast cancer, among others. The results have shown to be compatible with internationally reported data, and we have modified some application procedures towards to a better benefit for the patient and an optimization of the results. We present the overall results observed after 5 year of experimental clinical treatment.

  19. [First clinical experiences with ceramic ball attachments for overdentures].

    PubMed

    Büttel, Adrian E; Schmidli, Fredy; Marinello, Carlo P; Lüthy, Heinz

    2008-01-01

    In this prospective clinical study on 40 patients with similar clinical conditions (edentulous jaw with 2 interforaminal implants) commercially available ceramic ball attachments (ruby) were compared to commercial titanium ball attachments. The primary aim of the study was to measure the wear of the ball attachments after being 1 year in function. However, in the course of the study already after 7 to 12 months multiple failures with ceramic ball attachments occurred. Twelve (28%) of 43 ceramic ball attachments had to be replaced, mostly because of fractures (8) of the ceramic ball. It seems that ceramic ball attachments of the investigated design are not able to withstand normal intraoral stresses. The short-term susceptibility to fractures didn't allow to examine the ceramic-inherent features such as compressive strength and wear resistance. Furthermore, a secure connection between a titan base and a ceramic ball seems to be challenging. Based on these results, in implant-retained removable prosthesis the use of metal-based retainers is still recommended, although during maintenance a higher wear has to be expected. This wear can be compensated by either activating or changing the matrix or the patrix. PMID:18293602

  20. Gay men's experiences of surrogacy clinics in India.

    PubMed

    Riggs, Damien W; Due, Clemence; Power, Jennifer

    2015-01-01

    While growing numbers of Australian gay men are entering into 'offshore' surrogacy arrangements in order to become parents, little empirical research has been conducted with this population. This article reports on a qualitative analysis of interviews with 12 gay men who had entered into surrogacy arrangements in India. The findings outline both positive and negative experiences in terms of support pre-conception, during the birth and post-birth. Changes to legislation in India mean that gay men can no longer access surrogacy services there, but it is important to understand the experiences of men who had previously accessed those services. The article concludes by highlighting aspects of the data that demonstrate the particular experiences of gay men who undertake offshore surrogacy arrangements, especially with regard to their need for support and involvement in all aspects of the process. A more thoroughly developed network of care may help to facilitate such support and this may further increase the positive outcomes reported by gay men who form families through surrogacy arrangements. PMID:25351689

  1. Translating comparative effectiveness research into clinical practice: the UK experience.

    PubMed

    Walley, Tom

    2012-01-22

    Comparative effectiveness research (CER) is not new but its potential to improve the effectiveness of healthcare has not yet been exploited in the US. Other countries such as the UK have more experience of this. Key points of the UK experience are summarized here and some possible pointers for the US are drawn. These include the following: how to go beyond the evidence and apply judgements to make recommendations with authority and in a timely manner; how to implement these recommendations; how to identify suitable topics; and how to be open and transparently fair to all stakeholders. The quality of the science of CER is key but this needs developing, and not just in biomedical or statistical terms but also in how to understand public expectations, and how to implement its recommendations. A key issue is the role of health economics, which seems to have been marginalized by the CER legislation, but perhaps this is more apparent than real. Clearly this is a matter for much further debate. It is hard to see how CER can deliver its potential without active consideration of both benefits and costs. Although other countries have more experience of this than does the US, the context for such work is always very specific and the US will have to find its own way, while trying to avoid some of the errors made elsewhere. PMID:22268389

  2. Selecting clinical diagnoses: logical strategies informed by experience.

    PubMed

    Stanley, Donald Edward; Campos, Daniel G

    2016-08-01

    This article describes reasoning strategies used by clinicians in different diagnostic circumstances and how these modes of inquiry may allow further insight into the evaluation and treatment of patients. Specifically, it aims to make explicit the implicit logical considerations that guide a variety of strategies in the diagnostic process, as exemplified in specific clinical cases. It focuses, in particular, in strategies that clinicians use to move from a large set of possible diagnoses initially suggested by abductive inferences - the process of hypothesis generation that creates a diagnostic space - to a narrower set or even to a single 'best' diagnosis, where the criteria to determine what is 'best' may differ according to different strategies. Experienced clinicians should have a diversified kit of strategies - for example, Bayesian probability or inference to a lovely explanation - to select from among previously generated hypotheses, rather than rely on any one approach every time. PMID:26201314

  3. [Clinical experiences of RUAN's needling method for insomnia].

    PubMed

    Jiang, Ling-Zhen; Ruan, Bu-Qing

    2013-07-01

    The theoretical basis and needling techniques of RUAN's needling method in treatment of insomnia are introduced in this paper. Ruan's needling method follows the theory of traditional Chinese medicine and acupuncture, stresses the theory of taking brain as the marrow sea in treatment of insomnia acupuncture. The characteristics of his needling method are that emphasis on acupoints, including positioning accuracy and proper compatibility; think highly of needling method that combines with perpendicular needling, oblique needling, parallel needling, deep needling and shallow needling; emphasis on manipulation and identify qi under the needle to decide reinforcing or reducing method by arrival of qi, excess or deficiency. And the clinical observation of RUAN' s needling method on 30 cases of insomnia is attached. PMID:24032204

  4. [Experience in thyroglossal duct pathology: clinical case series].

    PubMed

    Cieri, Patricio; Udaquiola, Julia E; Calello, Santiago E; Libero, Daniel H

    2016-10-01

    The thyroglossal duct cyst pathology represents the second cause of bening cervical anomalies in childhood. Diagnosis is mainly clinical. Sistrunk (1920) proposed a surgical technique that is still considered the gold standard for definitive treatment of this condition. A retrospective study was made including patients who underwent surgery for thyroglossal duct cyst pathology in our department between June 2008 and August 2015. In this period, we performed 54 procedures in 45 patients (39 primary cases). Median age was 4.7 years; 14/39 patients (31.1%) had pre-operative infection. All patients were studied with neck ultrasound. A Sistrunk's procedure was performed in all cases. The global recurrence rate was 17.8% (8/45). PMID:27606652

  5. [Subantral augmentation with porous titanium in experiment and clinic].

    PubMed

    Sirak, S V; Shchetinin, E V; Sletov, A A

    2016-01-01

    The article discusses the use of porous titanium for subantral augmentation. Experimental study was conducted on 12 yearling rams. Subantral augmentation using porous titanium was performed in 33 patients. In the control group consisting of 14 patients calcium phosphates and bone collagen based agents ("Bio-Оss" and "Collost") were used. In the main and control groups 46 and 32 implant were placed, respectively. Pilot histological and clinical studies proved that the granules of porous titanium are biocompatible with bone tissue, provide the optimal surface microrelief, thus creating good conditions for adhesion, expansion and migration of osteoforming cells, have negligible kinetics of resorption, are porous to ensure effective neovascularization of de novo formed bone tissue. Porous titanium is an effective alternative material for subantral bone augmentation for dental implantation and reconstructive operations on the maxillary sinus. PMID:26925568

  6. An R package for simulation experiments evaluating clinical trial designs.

    PubMed

    Wang, Yuanyuan; Day, Roger

    2010-01-01

    This paper presents an open-source application for evaluating competing clinical trial (CT) designs using simulations. The S4 system of classes and methods is utilized. Using object-oriented programming provides extensibility through careful, clear interface specification; using R, an open-source widely-used statistical language, makes the application extendible by the people who design CTs: biostatisticians. Four key classes define the specifications of the population models, CT designs, outcome models and evaluation criteria. Five key methods define the interfaces for generating patient baseline characteristics, stopping rule, assigning treatment, generating patient outcomes and calculating the criteria. Documentation of their connections with the user input screens, with the central simulation loop, and with each other faciliates the extensibility. New subclasses and instances of existing classes meeting these interfaces can integrate immediately into the application. To illustrate the application, we evaluate the effect of patient pharmacokinetic heterogeneity on the performance of a common Phase I "3+3" design. PMID:21347151

  7. Clinical experience with aurora kinase inhibitors: a review.

    PubMed

    Boss, David S; Beijnen, Jos H; Schellens, Jan H M

    2009-08-01

    The aurora kinase family of serine/threonine kinases comprises three members, designated auroras A, B, and C. Auroras A and B are essential components of the mitotic pathway, ensuring proper chromosome assembly, formation of the mitotic spindle, and cytokinesis. The role of aurora C is less clear. Overexpression of aurora A and B has been observed in several tumor types, and has been linked with a poor prognosis of cancer patients. Several small molecules targeting aurora kinases A and B or both have been evaluated preclinically and in early phase I trials. In this review we aim to summarize the most recent advances in the development of aurora kinase inhibitors, with a focus on the clinical data. PMID:19684075

  8. The clinical presentation of celiac disease: experiences from northeastern iran.

    PubMed

    Ganji, Azita; Esmaielzadeh, Abbas; Aafzal Aghayee, Mehdi; Goshayeshi, Ladan; Ghaffarzadegan, Kamran

    2014-04-01

    BACKGROUND This study aimed to explore demographic characteristics and clinical presentations of celiac disease (CD) in Northeastern Iran. METHODS This was a cross-sectional retrospective study of 193 adults with CD who presented to Mashhad University Gastroenterology Clinic between 2008 and 2013. Patient data that included mode of presentation and the presence of any concomitant illnesses were collected. Intestinal biopsy and serum anti-tissue transglutaminase (anti-tTG) were used for diagnosis. Mucosal lesions were classified according to modified Marsh classification. RESULTS Overall, 132 females and 61 males, with a mean age at diagnosis of 32.6 ± 13.2 years were included. The patient's chief complaints in order of decreasing frequency were dyspepsia (24.6%), diarrhea (20%), anemia (12.8%), and flatulence (7.2%). Bone disease was seen (osteopenia, osteoporosis) in 30% of patients. A positive family history of CD was found in 17.9% of cases. There were 64% who had serum anti-tTG >200 units/ml and 78% had a Marsh classification grade 3 on duodenal biopsy. The histology grade (Marsh) did not show any correlation with anti-tTG serum levels, age, body mass index (BMI) or hemoglobin levels. CONCLUSION In Northeastern Iran, CD was seen more commonly in females and with non-diarrheal presentations. Abdominal discomfort, anemia and bone disease were most common primary presentations in this area. Histology grade showed no significant correlation with level of anti-tTG, BMI or hemoglobin levels. We suggest screening for CD in unexplained abdominal discomfort, bone disease and anemia. PMID:24872868

  9. Clinical profile, etiology, and management of hydropneumothorax: An Indian experience

    PubMed Central

    Kasargod, Vasunethra; Awad, Nilkanth Tukaram

    2016-01-01

    Introduction: Hydropneumothorax is an abnormal presence of air and fluid in the pleural space. Even though the knowledge of hydro-pneumothorax dates back to the days of ancient Greece, not many national or international literatures are documented. Aim: To study clinical presentation, etiological diagnosis, and management of the patients of hydropneumothorax. Materials and Methods: Patients admitted in a tertiary care hospital with diagnosis of hydropneumothorax between 2012 and 2014 were prospectively studied. Detailed history and clinical examination were recorded. Blood, pleural fluid, sputum investigations, and computed tomography (CT) thorax (if necessary) were done. Intercostal drainage (ICD) tube was inserted and patients were followed up till 3 months. Results: Fifty-seven patients were studied. Breathlessness, anorexia, weight loss, and cough were the most common symptoms. Tachypnea was present in 68.4% patients. Mean PaO2 was 71.7 mm of Hg (standard deviation ±12.4). Hypoxemia was present in 35 patients (61.4%). All patients had exudative effusion. Etiological diagnosis was possible in 35 patients by initial work-up and 22 required CT thorax for arriving at a diagnosis. Tuberculosis (TB) was etiology in 80.7% patients, acute bacterial infection in 14%, malignancy in 3.5%, and obstructive airway disease in 1.8%. All patients required ICD tube insertion. ICD was required for 24.8 days (±13.1). Conclusion: Most patients presented with symptoms and signs of cardiorespiratory distress along with cough, anorexia, and weight loss. Extensive pleural fluid analysis is essential in establishing etiological diagnosis. TB is the most common etiology. ICD for long duration with antimicrobial chemotherapy is the management. PMID:27185991

  10. Japanese experience with clinical trails of fast neutrons

    SciTech Connect

    Tsunemoto, H.; Arai, T.; Morita, S.; Ishikawa, T.; Aoki, Y.; Takada, N.; Kamata, S.

    1982-12-01

    Between November, 1975 and November, 1981, 825 patients were treated with 30 MeV (d-Be) neutrons at the National Institute of Radiological Sciences, Chiba. At the Institute of Medical Science, Tokyo, 302 patients were referred to the Radiation Therapy department and were treated with 16 MeV (d-Be) neutrons. The emphasis of these clinical trials with fast neutrons was placed on the estimation of the effect of fast neutrons for locally advanced cancers or radioresistant cancers, and on evaluation of the rate of complication of normal tissues following irradiaton with fast neutrons. Results were evaluated for patients with previously untreated cancer; local control of the tumor was observed in 59.1%. Complications requiring medical care developed in only 32 patients. Patients who had received pre- or postoperative irradiation were excluded from this evaluation. Late reaction of soft tissue seemed to be more severe than that observed with photon beams. The results also suggest that for carcinoma of the larynx, esophagus, uterine cervix, Pancoasts's tumor of the lung and osteosarcoma, fast neutrons were considered to be effectively applied in this randomized clinical trial. For carcinoma of the larynx, a fast nuetron boost was effectively delivered, although an interstitial implant was necessarily combined with fast neutrons for carcinoma of the tongue. The cumulative survival rate of the patients with carcinoma of the esophagus treated with fast neutrons was 26% compared to the survival rate of 10.5% obtained using photons. This was supported by evidence from the pathological studies that showed that the tumor cells which had deeply invaded into the esophagus were effectively destroyed when fast neutrons were applied.