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Sample records for hifu biological effect

  1. Effect of ribs in HIFU beam path on formation of coagulative necrosis in goat liver

    Science.gov (United States)

    Li, Faqi; Gong, Xiaobo; Hu, Kai; Li, Chongyan; Wang, Zhibiao

    2006-05-01

    The motives of the work are to explore the effect of ribs in HIFU beam path on HIFU ablation goat liver. A model-JC Focused Ultrasound Tumor Therapeutic System was used. A 0.75 MHz focused transducer with 150mm aperture and 120mm focal length was used in all experiment. Acoustical power can be adjusted. 30 goats were divided into control group (HIFU beam through rib cage, HIFU alone), experiment group 1(HIFU beam through rib cage, HIFU combined with microbubble) and experiment group 2(Ribs in HIFU beam path were surgically removed, HIFU alone). 20 targeted regions at 5cm away from skin surface were applied for creating necrosis with linear scanning of 15mm length using HIFU in 3 groups. All animals were sacrificed two days later and exposed organs were dissected. After obtaining the maximal section, the volumes of the necrotic regions were measured, then to calculate Energy Efficiency Factor (EEF). Researched results showed that Ribs in HIFU beam path affected the formation of coagulative necrosis and enhanced EEF in control group. HIFU combined with microbubble could enhance the formation of coagulative necrosis and decrease EEF.

  2. Combination of bubble liposomes and high-intensity focused ultrasound (HIFU) enhanced antitumor effect by tumor ablation.

    Science.gov (United States)

    Hamano, Nobuhito; Negishi, Yoichi; Takatori, Kyohei; Endo-Takahashi, Yoko; Suzuki, Ryo; Maruyama, Kazuo; Niidome, Takuro; Aramaki, Yukihiko

    2014-01-01

    Ultrasound (US) is used in the clinical setting not only for diagnosis but also for therapy. As a therapeutic US technique, high-intensity focused ultrasound (HIFU) can be applied to treat cancer in a clinical setting. Microbubbles increased temperature and improved the low therapeutic efficiency under HIFU; however, microbubbles have room for improvement in size, stability, and targeting ability. To solve these issues, we reported that "Bubble liposomes" (BLs) containing the US imaging gas (perfluoropropane gas) liposomes were suitable for ultrasound imaging and gene delivery. In this study, we examined whether BLs and HIFU could enhance the ablation area of the tumor and the antitumor effect. First, we histologically analyzed the tumor after BLs and HIFU. The ablation area of the treatment of BLs and HIFU was broader than that of HIFU alone. Next, we monitored the temperature of the tumor, and examined the antitumor effect. The temperature increase with BLs and HIFU treatment was faster and higher than that with HIFU alone. Moreover, treatment with BLs and HIFU enhanced the antitumor effect, which was better than with HIFU alone. Thus, the combination of BLs and HIFU could be efficacious for cancer therapy.

  3. Study on Enhancement Effect of Cavitation Caused by HIFU Piezoelectricity Transducer

    Institute of Scientific and Technical Information of China (English)

    Xinnan Fan; Changping Zhu; Shichuan He; Minglei Shan; Jiacai Chen

    2006-01-01

    An orthogonal ultrasonic irradiation system consisting of HIFU with frequency at 1.05 MHz combined with ultrasound with frequency at 28 kHz was applied in this paper. Effect of cavitation was detected by pH-value measurement and conductance measurement. The result shows that the effect of cavitation caused by ultrasound with frequency at 28 kHz is greatly enhanced by HIFU piezoelectricity transducer with frequency at 1.05 MHz.

  4. Effects of oxytocin on high intensity focused ultrasound (HIFU) ablation of adenomysis: A prospective study

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xin [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Zou, Min; Zhang, Cai [Department of Obstetrics and Gynecology, Chongqing Haifu Hospital, Chongqing 401121 (China); He, Jia [Department of Obstetrics and Gynecology, Suining Central Hospital, Sichuan 629000 (China); Mao, Shihua [Department of Obstetrics and Gynecology, Three Gorges Central Hospital, Chongqing 404000 (China); Wu, Qingrong [Department of Obstetrics and Gynecology, Fuling Central Hospital, Chongqing 408099 (China); He, Min [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Department of Obstetrics and Gynecology, Suining Central Hospital, Sichuan 629000 (China); Wang, Jian [Department of Obstetrics and Gynecology, Chongqing Haifu Hospital, Chongqing 401121 (China); Department of Obstetrics and Gynecology, Three Gorges Central Hospital, Chongqing 404000 (China); Zhang, Ruitao [Department of Obstetrics and Gynecology, Chongqing Haifu Hospital, Chongqing 401121 (China); Department of Obstetrics and Gynecology, Fuling Central Hospital, Chongqing 408099 (China); Zhang, Lian, E-mail: lianwzhang@yahoo.com [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Department of Obstetrics and Gynecology, Chongqing Haifu Hospital, Chongqing 401121 (China)

    2014-09-15

    Objective: To investigate the effects of oxytocin on high-intensity focused ultrasound (HIFU) ablation for the treatment of adenomyosis. Materials and methods: Eighty-six patients with adenomyosis from three hospitals were randomly assigned to the oxytocin group or control group for HIFU treatment. During HIFU treatment, 80 units of oxytocin was added in 500 ml of 0.9% normal saline running at the rate of 2 ml/min (0.32 U/min) in the oxytocin group, while 0.9% normal saline was used in the control group. Both patients and HIFU operators were blinded to oxytocin or saline application. Treatment results, adverse effects were compared. Results: When using oxytocin, the non-perfused volume (NPV) ratio was 80.7 ± 11.6%, the energy-efficiency factor (EEF) was 8.1 ± 9.9 J/mm{sup 3}, and the sonication time required to ablate 1 cm{sup 3} was 30.0 ± 36.0 s/cm{sup 3}. When not using oxytocin, the non-perfused volume ratio was 70.8 ± 16.7%, the EEF was 15.8 ± 19.6 J/mm{sup 3}, and the sonication time required to ablate 1 cm{sup 3} was 58.2 ± 72.7 S/cm{sup 3}. Significant difference in the NPV ratio, EEF, and the sonication time required to ablate 1 cm{sup 3} between the two groups was observed. No oxytocin related adverse effects occurred. Conclusion: Oxytocin could significantly decrease the energy for ablating adenomyosis with HIFU, safely enhance the treatment efficiency.

  5. MRI-based evaluation of MR-HIFU induced thermal effects

    NARCIS (Netherlands)

    Lam, M.K.

    2016-01-01

    High intensity focused ultrasound (HIFU) is novel technology for non-invasive thermal therapy and can be combined with magnetic resonance imaging (MRI). MRI-guided HIFU (MR-HIFU) allows for real-time acquisition of MRI scans during the HIFU treatment, for planning, monitoring and evaluation. The pur

  6. TU-A-210-01: HIFU Physics and Delivery

    Energy Technology Data Exchange (ETDEWEB)

    Eames, M. [Focused Ultrasound Foundation (United States)

    2015-06-15

    High-intensity focused ultrasound (HIFU) has developed rapidly in recent years and is used frequently for clinical treatments in Asia and Europe with increasing clinical use and clinical trial activity in the US, making it an important medical technology with which the medical physics community must become familiar. Akin to medical devices that deliver treatments using ionizing radiation, HIFU relies on emitter geometry to non-invasively form a tight focus that can be used to affect diseased tissue while leaving healthy tissue intact. HIFU is unique in that it does not involve the use of ionizing radiation, it causes thermal necrosis in 100% of the treated tissue volume, and it has an immediate treatment effect. However, because it is an application of ultrasound energy, HIFU interacts strongly with tissue interfaces, which makes treatment planning challenging. In order to appreciate the advantages and disadvantages of HIFU as a thermal therapy, it is important to understand the underlying physics of ultrasound tissue interactions. The first lecture in the session will provide an overview of the physics of ultrasound wave propagation; the mechanism for the accumulation of heat in soft-tissue; image-guidance modalities including temperature monitoring; current clinical applications and commercial devices; active clinical trials; alternate mechanisms of action (future of FUS). The second part of the session will compare HIFU to existing ionization radiation techniques. The difficulties in defining a clear concept of absorbed dose for HIFU will be discussed. Some of the technical challenges that HIFU faces will be described, with an emphasis on how the experience of radiation oncology physicists could benefit the field. Learning Objectives: Describe the basic physics and biology of HIFU, including treatment delivery and image guidance techniques. Summarize existing and emerging clinical applications and manufacturers for HIFU. Understand that thermal ablation with

  7. TU-A-210-00: HIFU Therapies - A Primer

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    High-intensity focused ultrasound (HIFU) has developed rapidly in recent years and is used frequently for clinical treatments in Asia and Europe with increasing clinical use and clinical trial activity in the US, making it an important medical technology with which the medical physics community must become familiar. Akin to medical devices that deliver treatments using ionizing radiation, HIFU relies on emitter geometry to non-invasively form a tight focus that can be used to affect diseased tissue while leaving healthy tissue intact. HIFU is unique in that it does not involve the use of ionizing radiation, it causes thermal necrosis in 100% of the treated tissue volume, and it has an immediate treatment effect. However, because it is an application of ultrasound energy, HIFU interacts strongly with tissue interfaces, which makes treatment planning challenging. In order to appreciate the advantages and disadvantages of HIFU as a thermal therapy, it is important to understand the underlying physics of ultrasound tissue interactions. The first lecture in the session will provide an overview of the physics of ultrasound wave propagation; the mechanism for the accumulation of heat in soft-tissue; image-guidance modalities including temperature monitoring; current clinical applications and commercial devices; active clinical trials; alternate mechanisms of action (future of FUS). The second part of the session will compare HIFU to existing ionization radiation techniques. The difficulties in defining a clear concept of absorbed dose for HIFU will be discussed. Some of the technical challenges that HIFU faces will be described, with an emphasis on how the experience of radiation oncology physicists could benefit the field. Learning Objectives: Describe the basic physics and biology of HIFU, including treatment delivery and image guidance techniques. Summarize existing and emerging clinical applications and manufacturers for HIFU. Understand that thermal ablation with

  8. Effect of hydrodynamic cavitation in the tissue erosion by pulsed high-intensity focused ultrasound (pHIFU)

    Science.gov (United States)

    Zhou, Yufeng; Gao, Xiaobin Wilson

    2016-09-01

    High-intensity focused ultrasound (HIFU) is emerging as an effective therapeutic modality in clinics. Besides the thermal ablation, tissue disintegration is also possible because of the interaction between the distorted HIFU bursts and either bubble cloud or boiling bubble. Hydrodynamic cavitation is another type of cavitation and has been employed widely in industry, but its role in mechanical erosion to tissue is not clearly known. In this study, the bubble dynamics immediately after the termination of HIFU exposure in the transparent gel phantom was captured by high-speed photography, from which the bubble displacement towards the transducer and the changes of bubble size was quantitatively determined. The characteristics of hydrodynamic cavitation due to the release of the acoustic radiation force and relaxation of compressed surrounding medium were found to associate with the number of pulses delivered and HIFU parameters (i.e. pulse duration and pulse repetition frequency). Because of the initial big bubble (~1 mm), large bubble expansion (up to 1.76 folds), and quick bubble motion (up to ~1 m s-1) hydrodynamic cavitation is significant after HIFU exposure and may lead to mechanical erosion. The shielding effect of residual tiny bubbles would reduce the acoustic energy delivered to the pre-existing bubble at the focus and, subsequently, the hydrodynamic cavitation effect. Tadpole shape of mechanical erosion in ex vivo porcine kidney samples was similar to the contour of bubble dynamics in the gel. Liquefied tissue was observed to emit towards the transducer through the punctured tissue after HIFU exposure in the sonography. In summary, the release of HIFU exposure-induced hydrodynamic cavitation produces significant bubble expansion and motion, which may be another important mechanism of tissue erosion. Understanding its mechanism and optimizing the outcome would broaden and enhance HIFU applications.

  9. TU-A-210-02: HIFU: Why Should a Radiation Oncology Physicist Pay Attention?

    Energy Technology Data Exchange (ETDEWEB)

    Schlesinger, D. [University of Virginia Health Systems (United States)

    2015-06-15

    High-intensity focused ultrasound (HIFU) has developed rapidly in recent years and is used frequently for clinical treatments in Asia and Europe with increasing clinical use and clinical trial activity in the US, making it an important medical technology with which the medical physics community must become familiar. Akin to medical devices that deliver treatments using ionizing radiation, HIFU relies on emitter geometry to non-invasively form a tight focus that can be used to affect diseased tissue while leaving healthy tissue intact. HIFU is unique in that it does not involve the use of ionizing radiation, it causes thermal necrosis in 100% of the treated tissue volume, and it has an immediate treatment effect. However, because it is an application of ultrasound energy, HIFU interacts strongly with tissue interfaces, which makes treatment planning challenging. In order to appreciate the advantages and disadvantages of HIFU as a thermal therapy, it is important to understand the underlying physics of ultrasound tissue interactions. The first lecture in the session will provide an overview of the physics of ultrasound wave propagation; the mechanism for the accumulation of heat in soft-tissue; image-guidance modalities including temperature monitoring; current clinical applications and commercial devices; active clinical trials; alternate mechanisms of action (future of FUS). The second part of the session will compare HIFU to existing ionization radiation techniques. The difficulties in defining a clear concept of absorbed dose for HIFU will be discussed. Some of the technical challenges that HIFU faces will be described, with an emphasis on how the experience of radiation oncology physicists could benefit the field. Learning Objectives: Describe the basic physics and biology of HIFU, including treatment delivery and image guidance techniques. Summarize existing and emerging clinical applications and manufacturers for HIFU. Understand that thermal ablation with

  10. A continuous tri-phase transition effect for HIFU-mediated intravenous drug delivery.

    Science.gov (United States)

    Zhang, Kun; Chen, Hangrong; Li, Faqi; Wang, Qi; Zheng, Shuguang; Xu, Huixiong; Ma, Ming; Jia, Xiaoqing; Chen, Yu; Mou, Juan; Wang, Xia; Shi, Jianlin

    2014-07-01

    Aiming at substantially enhanced efficacy and biosafety of clinical HIFU therapy, a natural solid medium, L-menthol (LM), characteristic of mild and controllable "solid-liquid-gas" (SLG) tri-phase transition, was adopted, instead of those conventional explosive liquid-gas (LG) bi-phase transitional media, in constructing a multifunctional theranostic system. Owing to the continuous and controllable characteristics of SLG tri-phase transition, such a novel tri-phase transition-based theranostic system has been demonstrated of the repeatedly enhanced HIFU efficacy ex vivo and in vivo under once intravenous injection and the significantly improved treatment precision, controllability and biosafety when comparing to the traditional bi-phase transition medium, perfluorohexane (PFH), thus promising great application potential in clinical HIFU treatment. Moreover, this theranostic system has been demonstrated a long blood-circulation lifetime and continuous accumulation in tumor in 24 h, which is very beneficial for the enhanced tumor ablation in vivo along with SLG tri-phase transition. More importantly, after loading multiple model drugs and real drug, such a theranostic system presents a HIFU-mediated temperature-responsive drug release property, and depending on the versatile miscibility of LM, co-loadings with hydrophobic and hydrophilic drugs are also achieved, which provides the possibility of synergistic treatment combining HIFU therapy and chemotherapy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Numerical study on the effective heating due to inertial cavitation in microbubble-enhanced HIFU therapy

    Science.gov (United States)

    Okita, Kohei; Sugiyama, Kazuyasu; Takagi, Shu; Matsumoto, Yoichiro

    2015-10-01

    The enhancement of heating due to inertial cavitation was focused in high-intensity focused ultrasound (HIFU) therapy. The influences of the rectified diffusion on microbubble-enhanced HIFU were examined numerically. A bubble dynamics equation in consideration of the spherical shell bubble and the elasticity of surrounding tissue was employed. Mass and heat transfer between the surrounding medium and the bubble were considered. The basic equations were discretized by finite difference method. The mixture phase and bubbles are coupled by the Euler-Lagrange method to take into account the interaction between ultrasound and bubbles. The mass transfer rate of gas from the surrounding medium to the bubble was examined as function of the initial bubble radius and the driving pressure amplitude. As the results, the pressure required to bubble growth was decreases with increasing the initial bubble radius. Thus, the injection of microbubble reduces the cavitation threshold pressure. On the other hand, the influence of the rectified diffusion on the triggered HIFU therapy which generates cavitation bubbles by high-intensity burst and induces the localized heating owing to cavitation bubble oscillation by low-intensity continuous waves. The calculation showed that the localized heating was enhanced by the increase of the equilibrium bubble size due to the rectified diffusion.

  12. Variational method for estimating the effects of continuously varying lenses in HIFU, sonography, and sonography-based cross-correlation methods.

    Science.gov (United States)

    Alaniz, Alex; Kallel, Faouzi; Hungerford, Ed; Ophir, Jonathan

    2002-01-01

    The effects of high intensity focused ultrasound (HIFU)-induced continuously varying thermal gradients on sound ray propagation were modeled theoretically. This modeling was based on Fermat's variational principle of least time for rays propagating in a continuously varying thermal gradient described by a radially symmetric heat equation. Such thermal lenses dynamically affect HIFU beam focusing, and simultaneously create ultrasonic geometric and intensity distortions and artifacts in monitoring devices. Techniques which are based upon ultrasonic cross-correlation methods, such as elastography and two-dimensional temperature estimation, also suffer distortion effects and generate artifacts.

  13. Safety Issues for HIFU Transducer Design

    Science.gov (United States)

    Fleury, Gérard; Berriet, Rémi; Chapelon, Jean Yves; ter Haar, Gail; Lafon, Cyril; Le Baron, Olivier; Chupin, Laurent; Pichonnat, Fabrice; Lenormand, Jérôme

    2005-03-01

    In contrast with most ultrasound modalities for medical applications, (especially ultrasound imaging), High Intensity Focused Ultrasound (HIFU) involves technologies and procedures which may present risk to the patient. These risks, resulting from the high power levels required for effective therapy, should be taken into account at the earliest stages in the design of a system dedicated to HIFU treatment. An understanding of these risks must thus be shared amongst the many players in the field of therapy using high power ultrasound. Moreover, since the number of applications of HIFU has increased appreciably over recent years and the technology is ready to move from the research to the industrial level, it is worth now considering solutions that should be put in place to guarantee the safety of the patient during HIFU treatment. This paper reports thoughts on this, identifies some risks to the patient that must be taken into consideration in the design of HIFU transducers, and proposes some solutions that could prevent the deleterious consequences of transducer misuse or failure. For the main risks identified, such as exceeding the desired acoustic power or poor control of tissue targeting, a description of transducer performance that could potentially result in problems is systematically sought. This allows proposals for precautions to be taken during operation to be made. Parameters which should be monitored to ensure safe use are also suggested. This type of approach, which should be undertaken for the different components of a therapeutic system, highlights the challenges that must be faced in the immediate future for the development and safe exploitation of HIFU systems. The necessity for standard definitions of the parameters to be checked or monitored during HIFU treatments is crucial in this approach, as is the availability of reliable dedicated measurement devices. Co-ordinated action on these topics in the HIFU community would contribute to the

  14. Experimental Study on the Effect of High-intensity Focused Ultrasound (HIFU) Using Sonablate-500 in the Ablation of Canine Prostate

    Institute of Scientific and Technical Information of China (English)

    LU Jun; YE Zhangqun; WANG Wei; CHEN Zhaoyang; ZHANG Yuanfeng; HU Weilie

    2007-01-01

    To investigate the safety, feasibility and effectiveness of transrectal high-intensity focused ultrasound (HIFU) in the ablation of canine prostate, 20 dogs were divided randomly into 5 groups.Sixteen canine prostates were treated with the third-generation transrectal HIFU device (Sonablate-500 TM). Transrectal ultrasound images of the prostate and prostatic urethra were observed preoperatively and postoperatively. Serial study was performed 30 min, 30 days, 60 days and 180 days after the therapy. The rectum, periprostatic tissues, and prostate were excised en bloc and the tissues were fixed for gross and histological analysis. Our results showed that the average maximal diameter of prostatic urethra was 0.59±0.11 cm before the operation and 2.57±0.98 cm 60 days after the operation. The volume of prostate was 6.5±3.12 cm3 before the treatment while the volume was 4.13±0.23 cm3 60 days after the treatment and the differences were statistically significant (P<0.05).Histologically, there was a clear demarcation between the necrotic area of the treated tissues and the unaffected surrounding tissues. All the necrotic tissues in the targeted zone broke off and the prostatic urethra became cavitary 60 days later. The more frequent complications were urinary retention and frequency and hematuria. No rectal injury occurred during the treatment. It is concluded that the third-generation transrectal HIFU is capable of destroying prostatic tissue, substantially increasing the width of the prostatic urethra without causing injury to the adjacent tissues. The risk of postoperative complications associated with HIFU was low. HIFU may become a safe, effective and minimally invasive alternative for the treatment of prostatic diseases..

  15. The effect of pulsed HIFU on the porosity and permeability of collagen gels: An in vitro study

    Science.gov (United States)

    Vipulanandan, Geethanjali; O'Neill, Brian E.

    2012-10-01

    Pulsed HIFU is hypothesized to alter permeability of the extracellular matrix by altering the collagen network. In this study, the ability of HIFU to disrupt the extracellular matrix, particularly Type I collagen, in vitro, was investigated in order to enhance the drug delivery to highly collagenous tumors. This was tested in vitro in two ways, first using dye penetration, and second, by confocal reflection microscopy. Based on the analyses, it was concluded that there was at least a three-fold increase in porosity of the collagen gels after HIFU treatment.

  16. Experimental investigation of thermal effects in HIFU-based external valvuloplasty with a non-spherical transducer, using high-resolution MR thermometry

    Science.gov (United States)

    Petrusca, Lorena; Salomir, Rares; Milleret, Réné; Pichot, Olivier; Rata, Mihaela; Cotton, François; Chapelon, Jean-Yves

    2009-09-01

    Real-time image-guided extracorporeal high intensity focused ultrasound (HIFU) has been suggested for minimally invasive treatment of valvular dysfunction in the saphenous vein. Local application of heat on the perimeter of the valve zone was previously reported to induce a partial shrinkage of the collagen, which may correct valvular function. In our study, a novel MR compatible HIFU device has been investigated. This device is based on a non-spherical geometry, with two active elements that create a focusing line which is orthogonal to the beam main axis, aiming to cover the valve longitudinally. The prototype performance was characterized by electro-acoustical measurements of the pressure field and by high-resolution MR thermometry. Pressure and thermal fields were found in good agreement with the theoretical predictions. To investigate the therapeutic potential, fresh samples of excised human veins were filled with an agarose gel, embedded in porcine muscle and exposed to HIFU. The power level applied during a fixed duration of 30 s was varied such that the absolute temperature at focus ranged between 52 °C and 83 °C. Targeting was achieved under MR guidance using a MR compatible XZ positioning system. A dedicated waterproof miniature loop coil was specifically built to achieve high-resolution MRI image-based targeting (0.25 mm × 0.25 mm × 3 mm voxel) and thermometry (0.4 mm × 0.4 mm × 4 mm voxel). The vein wall was clearly identified on MR images before and after HIFU treatment. The thermal buildup created by the non-spherical transducer could be characterized from MR thermometry data. Shrinkage of the vein wall (above 65 °C) was determined by absolute temperature and was not a cumulative thermal dose effect.

  17. Experimental investigation of thermal effects in HIFU-based external valvuloplasty with a non-spherical transducer, using high-resolution MR thermometry

    Energy Technology Data Exchange (ETDEWEB)

    Petrusca, Lorena; Salomir, Rares; Milleret, Rene; Pichot, Olivier; Rata, Mihaela; Chapelon, Jean-Yves [Inserm, U556, and Universite de Lyon, Lyon, F-69003 (France); Cotton, Francois [Universite Claude Bernard Lyon 1, Lyon, F-69003 (France)], E-mail: lorena.petrusca@inserm.fr

    2009-09-07

    Real-time image-guided extracorporeal high intensity focused ultrasound (HIFU) has been suggested for minimally invasive treatment of valvular dysfunction in the saphenous vein. Local application of heat on the perimeter of the valve zone was previously reported to induce a partial shrinkage of the collagen, which may correct valvular function. In our study, a novel MR compatible HIFU device has been investigated. This device is based on a non-spherical geometry, with two active elements that create a focusing line which is orthogonal to the beam main axis, aiming to cover the valve longitudinally. The prototype performance was characterized by electro-acoustical measurements of the pressure field and by high-resolution MR thermometry. Pressure and thermal fields were found in good agreement with the theoretical predictions. To investigate the therapeutic potential, fresh samples of excised human veins were filled with an agarose gel, embedded in porcine muscle and exposed to HIFU. The power level applied during a fixed duration of 30 s was varied such that the absolute temperature at focus ranged between 52 deg. C and 83 deg. C. Targeting was achieved under MR guidance using a MR compatible XZ positioning system. A dedicated waterproof miniature loop coil was specifically built to achieve high-resolution MRI image-based targeting (0.25 mm x 0.25 mm x 3 mm voxel) and thermometry (0.4 mm x 0.4 mm x 4 mm voxel). The vein wall was clearly identified on MR images before and after HIFU treatment. The thermal buildup created by the non-spherical transducer could be characterized from MR thermometry data. Shrinkage of the vein wall (above 65 deg. C) was determined by absolute temperature and was not a cumulative thermal dose effect.

  18. MR Guidance, Monitoring and Control of Brain HIFU Therapy in Small Animals: In Vivo Demonstration in Rats

    Science.gov (United States)

    Larrat, B.; Pernot, M.; Dervishi, E.; Souilah, A.; Seilhean, D.; Marie, Y.; Boch, A. L.; Aubry, J. F.; Fink, M.; Tanter, M.

    2010-03-01

    In the framework of HIFU transcranial brain therapy, it is mandatory to develop techniques capable of assessing the focusing quality and location before the treatment. Monitoring heat deposition in real time and verifying the extension of the treated area are also important steps. In this study, an imaging protocol is proposed to:1/ locate the US radiation force induced displacement in tissues and quantify the acoustic pressure at focus prior to HIFU; 2/ monitor the temperature rise during HIFU; and 3/ assess the changes in elasticity in the treated area. A 7T MRI scanner was equipped with a home-made stereotactic frame for rats and a US focused transducer working at 1.5 MHz. Such a tool is key for the evaluation of the biological effects of HIFU on brain tissue and tumors. The proposed protocol was successfully tested on 12 rats with and without injected tumors. The accurate localization of the focal point prior to HIFU was demonstrated in vivo. Furthermore, the pressure estimation in situ allowed to accurately simulate the heat deposition at focus and to plan the treatment (electrical power, duration). The temperature measurements were in good accordance with the predicted curves. The elasticity maps showed significant changes after treatment in some cases.

  19. Cavitation and the relationship between cavitation, echo and the thermal effects of HIFU treatment%高强度聚焦超声治疗中的空化及其与回声、热效应之间的关系

    Institute of Scientific and Technical Information of China (English)

    陈杰; 易华容; 王彬; 李发琪

    2009-01-01

    High intensity focused ultrasound (HIFU) is a new and exciting medical treatment. Cavitation is the focus in the field of HIFU research. Cavitation and the relationship between cavitation, echo and the thermal effects of HIFU treatment were reviewed in this article.%高强度聚焦超声(HIFU)正在成为医学上一种新兴的治疗技术.HIFU治疗中的空化一直是HIFU研究中的热点问题.本文介绍HIFU治疗中的空化及其与回声、热效应之间的关系.

  20. Blood coagulation using High Intensity Focused Ultrasound (HIFU)

    Science.gov (United States)

    Nguyen, Phuc V.; Oh, Junghwan; Kang, Hyun Wook

    2014-03-01

    High Intensity Focused Ultrasound (HIFU) technology provides a feasible method of achieving thermal coagulation during surgical procedures. One of the potential clinical benefits of HIFU can induce immediate hemostasis without suturing. The objective of this study was to investigate the efficiency of a HIFU system for blood coagulation on severe vascular injury. ngHIFU treatment was implemented immediately after bleeding in artery. The ultrasound probe was made of piezoelectric material, generating a central frequency of 2.0 MHz as well as an ellipsoidal focal spot of 2 mm in lateral dimension and 10 mm in axial dimension. Acoustic coagulation was employed on a perfused chicken artery model in vitro. A surgical incision (1 to 2 mm long) was made with a scapel on the arterial wall, and heparinized autologous blood was made to leak out from the incision with a syringe pump. A total of 5 femoral artery incisions was treated with the HIFU beam. The intensity of 4500 W/cm2 at the focus was applied for all treatments. Complete hemostasis was achieved in all treatments, along with the treatment times of 25 to 50 seconds. The estimated intraoperative blood loss was from 2 to 5 mL. The proposed HIFU system may provide an effective method for immediate blood coagulation for arteries and veins in clinical applications.

  1. High intensity focused ultrasound (HIFU) focal spot localization using harmonic motion imaging (HMI).

    Science.gov (United States)

    Han, Yang; Hou, Gary Yi; Wang, Shutao; Konofagou, Elisa

    2015-08-07

    Several ultrasound-based imaging modalities have been proposed for image guidance and monitoring of high-intensity focused ultrasound (HIFU) treatment. However, accurate localization and characterization of the effective region of treatment (focal spot) remain important obstacles in the clinical implementation of HIFU ablation. Harmonic motion imaging for focused ultrasound (HMIFU) is a HIFU monitoring technique that utilizes radiation-force-induced localized oscillatory displacement. HMIFU has been shown to correctly identify the formation and extent of HIFU thermal ablation lesions. However a significant problem remains in identifying the location of the HIFU focus, which is necessary for treatment planning. In this study, the induced displacement was employed to localize the HIFU focal spot inside the tissue prior to treatment. Feasibility was shown with two separate systems. The 1D HMIFU system consisted of a HIFU transducer emitting an amplitude-modulated HIFU beam for mechanical excitation and a confocal single-element, pulse-echo transducer for simultaneous RF acquisition. The 2D HIFU system consists of a HIFU phased array, and a co-axial imaging phased array for simultaneous imaging. Initial feasibility was first performed on tissue-mimicking gelatin phantoms and the focal zone was defined as the region corresponding to the -3dB full width at half maximum of the HMI displacement. Using the same parameters, in vitro experiments were performed in canine liver specimens to compare the defined focal zone with the lesion. In vitro measurements showed good agreement between the HMI predicted focal zone and the induced HIFU lesion location. HMIFU was experimentally shown to be capable of predicting and tracking the focal region in both phantoms and in vitro tissues. The accuracy of focal spot localization was evaluated by comparing with the lesion location in post-ablative tissues, with a R(2) = 0.821 at p tissue ablation and can be fully integrated into any HMI

  2. Motion tracing system for ultrasound guided HIFU

    Science.gov (United States)

    Xiao, Xu; Jiang, Tingyi; Corner, George; Huang, Zhihong

    2017-03-01

    One main limitation in HIFU treatment is the abdominal movement in liver and kidney caused by respiration. The study has set up a tracking model which mainly compromises of a target carrying box and a motion driving balloon. A real-time B-mode ultrasound guidance method suitable for tracking of the abdominal organ motion in 2D was established and tested. For the setup, the phantoms mimicking moving organs are carefully prepared with agar surrounding round-shaped egg-white as the target of focused ultrasound ablation. Physiological phantoms and animal tissues are driven moving reciprocally along the main axial direction of the ultrasound image probe with slightly motion perpendicular to the axial direction. The moving speed and range could be adjusted by controlling the inflation and deflation speed and amount of the balloon driven by a medical ventilator. A 6-DOF robotic arm was used to position the focused ultrasound transducer. The overall system was trying to estimate to simulate the actual movement caused by human respiration. HIFU ablation experiments using phantoms and animal organs were conducted to test the tracking effect. Ultrasound strain elastography was used to post estimate the efficiency of the tracking algorithms and system. In moving state, the axial size of the lesion (perpendicular to the movement direction) are averagely 4mm, which is one third larger than the lesion got when the target was not moving. This presents the possibility of developing a low-cost real-time method of tracking organ motion during HIFU treatment in liver or kidney.

  3. Evaluation of temperature rise in a tissue mimicking material during HIFU exposure

    Energy Technology Data Exchange (ETDEWEB)

    Maruvada, S; Liu, Y; Herman, B A; Harris, G R, E-mail: subha.maruvada@fda.hhs.gov [Food and Drug Administration, Center for Devices and Radiological Health, 10903 New Hampshire Ave., Bldg., Silver Spring, MD 20993 (United States)

    2011-02-01

    In pre-clinical testing it is essential to characterize clinical high intensity focused ultrasound (HIFU) devices using tissue-mimicking materials (TMMs) with well known characteristics, including temperature rise and cavitation properties. The purpose of this study was to monitor cavitation behavior and correlate its effect with temperature rise in a HIFU TMM containing an embedded thermocouple. A 75-{mu}m fine wire thermocouple was embedded in a hydrogel-based TMM previously developed for HIFU. HIFU at 1.1 and 3.3 MHz was focused at the thermocouple junction. Focal pressures from 1-11 MPa were applied and the temperature profiles were recorded. Three hydrophones were used to monitor cavitation activity during sonication. A hydrophone confocal with the HIFU transducer and a cylindrical hydrophone lateral to the HIFU beam were used as passive cavitation detectors for spectral analysis of signals, and a needle hydrophone placed beyond the HIFU focus was used to record changes in the pressure amplitude due to blockage by bubbles at or near the focus. B-mode imaging scans were employed to visualize bubble presence during sonication. In a separate measurement, schlieren imaging was used to monitor the change in field distribution behind the TMM. All hydrophone methods correlated well with cavitation in the TMM.

  4. Feasibility of laser-integrated high intensity focused ultrasound (HIFU) treatment for bladder tumors: in vitro study (Conference Presentation)

    Science.gov (United States)

    Nguyen, Van Phuc; Park, Suhyun; Oh, Junghwan; Kang, Hyun Wook

    2016-02-01

    Previous studies have shown that photothemal therapy combined with high intensity focused ultrasound (HIFU) can provide a promising method to achieve rapid thermal coagulation during surgical procedures. The current study investigated the feasibility of the laser-integrated high intensity focused ultrasound (HIFU) application to treat bladder tumors by enhancing thermal effects and therapeutic depth in vitro. To generate thermal coagulation, a single element HIFU transducer with a central frequency of 2.0 MHz was used to transmit acoustic energy to 15 fresh porcine bladders injected with an artificial tumor (100 µl gelatin and hemoglobin solution) in vitro. Simultaneously, an 80-W 532-nm laser system was also implemented to induce thermal necrosis in the targeted tissue. The intensity of 570 W/cm2 at the focus of HIFU and laser energy of 0.9 W were applied to all the samples for 40 s. The temperature rise increased up to about 1.6 or 3 folds (i.e., ΔT=32±3.8 K for laser-integrated HIFU, ΔT=20±6.5 K for HIFU only, and ΔT=11±5.6 K for laser only). The estimated lesion depth also increased by 1.3 and 2 folds during the dual-thermal treatment, in comparison with the treatment by either HIFU or laser. The results indicated that the laser-integrated HIFU treatment can be an efficient hyperthermic method for tumor coagulation.

  5. Development of a HIFU Phantom

    Science.gov (United States)

    King, Randy L.; Herman, Bruce A.; Maruvada, Subha; Wear, Keith A.; Harris, Gerald R.

    2007-05-01

    The field of high intensity focused ultrasound (HIFU) is developing rapidly. For basic research, quality control, and regulatory assessment a reusable phantom that has both thermal and acoustic properties close to that of soft tissue is critical. A hydrogel-based tissue mimicking material (TMM) has been developed that shows promise for such a phantom. The acoustic attenuation, speed of sound, B/A, thermal diffusivity and conductivity, as well as the cavitation threshold, were measured and found to mimic published values for soft tissue. The attenuation of 0.53f1.04 from 1 MHz to 8 MHz, as well as the sound speed of 1565 m/s and the tissue-like image quality, indicate the usefulness of the TMM for ultrasound imaging applications. These properties along with the thermal conductivity of 0.58 W/m- °C, diffusivity of 0.15 (mm2)/s, and the ability to withstand temperatures above 95 °C make this material appropriate for HIFU applications. The TMM also allows for the embedding of thermocouples and the formation of wall-less vessels that do not deteriorate as a result of continuous flow of blood mimicking fluids through the material. Tissue characteristics are strongly dependent on the fabrication technique, and care must be taken to achieve reproducible results. Note: This research was supported by the Defense Advanced Research Projects Agency (DARPA).

  6. Emerging HIFU applications in cancer therapy.

    Science.gov (United States)

    Maloney, Ezekiel; Hwang, Joo Ha

    2015-05-01

    High intensity focused ultrasound (HIFU), is a promising, non-invasive modality for treatment of tumours in conjunction with magnetic resonance imaging or diagnostic ultrasound guidance. HIFU is being used increasingly for treatment of prostate cancer and uterine fibroids. Over the last 10 years a growing number of clinical trials have examined HIFU treatment of both benign and malignant tumours of the liver, breast, pancreas, bone, connective tissue, thyroid, parathyroid, kidney and brain. For some of these emerging indications, HIFU is poised to become a serious alternative or adjunct to current standard treatments--including surgery, radiation, gene therapy, immunotherapy, and chemotherapy. Current commercially available HIFU devices are marketed for their thermal ablation applications. In the future, lower energy treatments may play a significant role in mediating targeted drug and gene delivery for cancer treatment. In this article we introduce currently available HIFU systems, provide an overview of clinical trials in emerging oncological targets, and briefly discuss selected pre-clinical research that is relevant to future oncological HIFU applications.

  7. Segmentation of tumor ultrasound image in HIFU therapy based on texture and boundary encoding.

    Science.gov (United States)

    Zhang, Dong; Xu, Menglong; Quan, Long; Yang, Yan; Qin, Qianqing; Zhu, Wenbin

    2015-03-07

    It is crucial in high intensity focused ultrasound (HIFU) therapy to detect the tumor precisely with less manual intervention for enhancing the therapy efficiency. Ultrasound image segmentation becomes a difficult task due to signal attenuation, speckle effect and shadows. This paper presents an unsupervised approach based on texture and boundary encoding customized for ultrasound image segmentation in HIFU therapy. The approach oversegments the ultrasound image into some small regions, which are merged by using the principle of minimum description length (MDL) afterwards. Small regions belonging to the same tumor are clustered as they preserve similar texture features. The mergence is completed by obtaining the shortest coding length from encoding textures and boundaries of these regions in the clustering process. The tumor region is finally selected from merged regions by a proposed algorithm without manual interaction. The performance of the method is tested on 50 uterine fibroid ultrasound images from HIFU guiding transducers. The segmentations are compared with manual delineations to verify its feasibility. The quantitative evaluation with HIFU images shows that the mean true positive of the approach is 93.53%, the mean false positive is 4.06%, the mean similarity is 89.92%, the mean norm Hausdorff distance is 3.62% and the mean norm maximum average distance is 0.57%. The experiments validate that the proposed method can achieve favorable segmentation without manual initialization and effectively handle the poor quality of the ultrasound guidance image in HIFU therapy, which indicates that the approach is applicable in HIFU therapy.

  8. Intra-operative Hemostasis of Punctured Femoral Artery Using HIFU: A Survival Study

    Science.gov (United States)

    Zderic, Vesna; Keshavarzi, Amid; Noble, Misty L.; Paun, Marla; Sharar, Sam R.; Crum, Lawrence A.; Martin, Roy W.; Vaezy, Shahram

    2005-03-01

    The objective was to investigate the long-term efficacy of hemostasis and healing of arteries after HIFU application. The femoral arteries of 22 adult rabbits were surgically exposed. Fifteen arteries were punctured with a needle and treated with HIFU, and 7 arteries were sham-treated (no puncture or HIFU was applied). The tip of the HIFU applicator was positioned on the bleeding site, and HIFU energy was applied until hemostasis was achieved. The focal intensity was approximately 3,000 W/cm2, at the resonant frequency of 9.6 MHz. Serial ultrasound images, blood and tissue samples were collected immediately and on days 1, 3, 7, 14, 28, and 60 after the treatment. Eleven of the arteries were patent after the treatment, and four arteries were occluded, as confirmed using Doppler imaging. One of the occluded arteries reopened at day 14. HIFU exposure time to achieve hemostasis was 27 ±17 seconds for patent arteries and 101±38 seconds for the occluded arteries. The blood flow velocities were not statistically different between HIFU-treated patent vessels and sham-treated vessels. The tunica adventitia and media, disrupted and coagulated immediately after the treatment, recovered to normal appearance within 28 days, with localized thinning of the tunica media observed up to day 60. Neo-intimal hyperplasia was observed in the arteries at days 14 and 28. HIFU produced an effective and long-term (up to 60 days) hemostasis of injured femoral arteries while preserving a normal blood flow and vessel wall structure in the majority of vessels.

  9. Report on research of calculus fragmentation by HIFU-induced cavitation in Tsinghua University: 1. Effects of tissue-mimicking phantom

    Science.gov (United States)

    Zuo, Z. G.; Liu, S. H.

    2012-11-01

    Study of the acoustic attenuation through human tissues was carried out, in order to accurately evaluate the damaging power of the generated cavitation cloud. Tissue phantom was made, with acoustic properties (acoustic speed and acoustic attenuation factor) similar to human tissues. Preliminary results show that, with the increase of intensity and acting time of the HIFU acoustic waves, the depths of the craters increase rapidly, while the radii of the craters increase mildly. Mass loss of the artificial stones in phantom is less than in water (about 50%), indicating considerable energy dissipation in tissues.

  10. Development of Noninvasive Vascular Occlusion Method with HIFU

    Science.gov (United States)

    Senoo, Naohiko; Suzuki, Jun; Yoshinakaa, Kiyoshi; Deguchi, Juno; Takagia, Shu; Miyata, Tetsuro; Matsumotoa, Yoichiro

    2010-03-01

    HIFU treatment with microbubbles is investigated in the present study. It is well known that microbubbles have the potential to enhance the heating effect in an ultrasound field. In the present study, the heat produced by microbubble oscillation was used to occlude varicose veins. The heated area by HIFU irradiation was initially investigated with white-egg gel, which denatures at over 70° C. The heated area mainly depends on the frequency of the ultrasound, the intensity at focus, and the irradiation time. The attenuation coefficient was also measured in order to confirm that attenuation at the skin is such that HIFU energy can reach the vein. Then, we conducted an animal experiment. We completely dehaired a rabbit and washed the exposed skin with soap and degassed water in order to eliminate bubbles (which interfere with the passage of ultrasound) from the boundary face. The frequency of the ultrasound was 1.7 MHz. The intensity at focus was 1,800 W/cm2, and the irradiation time was 20 s. We chose the contrast agent Levovist® for the microbubbles, and set the void fraction (the ratio of total gas volume to liquid) in the blood vessel to 10-5. Levovist® was dissolved into normal saline and injected into the vein. The vein was clasped on one side using forceps and compressed in order to avoid thermal dissipation. Furthermore, hypodermic water was injected as coolant for skin. Then, the external jugular vein of rabbit was occluded. The capability of HIFU treatment to occlude lower extremity varicose veins was verified in the present study.

  11. Nanoparticle-enhanced synergistic HIFU ablation and transarterial chemoembolization for efficient cancer therapy

    Science.gov (United States)

    You, Yufeng; Wang, Zhigang; Ran, Haitao; Zheng, Yuanyi; Wang, Dong; Xu, Jinshun; Wang, Zhibiao; Chen, Yu; Li, Pan

    2016-02-01

    High-intensity focused ultrasound (HIFU) is being generally explored as a non-invasive therapeutic modality to treat solid tumors. However, the clinical use of HIFU for large and deep tumor-ablation applications such as hepatocellular carcinoma (HCC) is currently entangled with long treatment duration and high operating energy. This critical issue can be potentially resolved by the introduction of HIFU synergistic agents (SAs). Traditional SAs such as microbubbles and microparticles face the problem of large size, short cycle time, damage to mononuclear phagocytic system and unsatisfactory targeting efficiency. In this work, we have developed a facile and versatile nanoparticle-based HIFU synergistic cancer surgery enhanced by transarterial chemoembolization for high-efficiency HCC treatment based on elaborately designed Fe3O4-PFH/PLGA nanocapsules. Multifunctional Fe3O4-PFH/PLGA nanocapsules were administrated into tumor tissues via transarterial injection combined with Lipiodol to achieve high tumor accumulation because transarterial chemoembolization by Lipiodol could block the blood vessels. The high synergistic HIFU ablation effect was successfully achieved against HCC tumors based on the phase-transformation performance of the perfluorohexane (PFH) inner core in the composite nanocapsules, as systematically demonstrated in VX2 liver tumor xenograft in rabbits. Multifunctional Fe3O4-PFH/PLGA nanocapsules were also demonstrated as efficient contrast agents for ultrasound, magnetic resonance and photoacoustic tri-modality imagings, potentially applicable for imaging-guided HIFU synergistic surgery. Therefore, the elaborate integration of traditional transarterial chemoembolization with recently developed nanoparticle-enhanced HIFU cancer surgery could efficiently enhance the HCC cancer treatment outcome, initiating a new and efficient therapeutic protocol/modality for clinic cancer treatment.

  12. Dependence of Boiling Histotripsy Treatment Efficiency on HIFU Frequency and Focal Pressure Levels.

    Science.gov (United States)

    Khokhlova, Tatiana D; Haider, Yasser A; Maxwell, Adam D; Kreider, Wayne; Bailey, Michael R; Khokhlova, Vera A

    2017-09-01

    Boiling histotripsy (BH) is a high-intensity focused ultrasound (HIFU)-based method of mechanical tissue fractionation that utilizes millisecond-long bursts of HIFU shock waves to cause boiling at the focus in milliseconds. The subsequent interaction of the incoming shocks with the vapor bubble mechanically lyses surrounding tissue and cells. The acoustic parameter space for BH has been investigated previously and an inverse dependence between the HIFU frequency and the dimensions of a BH lesion has been observed. The primary goal of the present study was to investigate in more detail the ablation rate and reliability of BH in the frequency range relevant to treatment of deep abdominal tissue targets (1-2 MHz). The second goal was to investigate the effect of focal peak pressure levels and shock amplitude on BH lesion formation, given a constant duty factor, a constant ratio of the pulse duration to the time to reach boiling and a constant number of BH pulses. A custom-built 12-element sector array HIFU transducer with F-number = 1.05 was used in all experiments. BH pulses at 5 different frequencies (1, 1.2, 1.5, 1.7 and 1.9 MHz) were delivered to optically transparent polyacrylamide gel phantoms and ex vivo bovine liver and myocardium tissue to observe cavitation and boiling bubble activity with high-speed photography and B-mode ultrasound imaging, correspondingly. In gel phantoms, a cavitation bubble cloud was shown to form prefocally and to shield the focus in all exposures at 1 and 1.2 MHz and in the highest amplitude exposures at 1.5-1.7 MHz; shielding was not observed at 1.9 MHz. In ex vivo tissue, this shielding effect was observed in 25% of exposures when peak negative in situ pressure exceeded 10.2 MPa at 1 MHz and 14.5 MPa at 1.5 MHz. When shielding occurred, the exposures resulted in mild tissue disruption in the prefocal region, but not liquefaction. The dimensions of liquefied lesions followed the inverse proportionality trend with

  13. Cavitation damage in blood clots under HIFU

    Science.gov (United States)

    Weiss, Hope; Ahadi, Golnaz; Hoelscher, Thilo; Szeri, Andrew

    2010-11-01

    High Intensity Focused Ultrasound (HIFU) has been shown to accelerate thrombolysis, the dissolution of blood clots, in vitro and in vivo, for treatment of ischemic stroke. Cavitation in sonothrombolysis is thought to play an important role, although the mechanisms are not fully understood. The damage to a blood clot associated with bubble collapses in a HIFU field is studied. The region of damage caused by a bubble collapse on the fibrin network of the blood clot exposed to HIFU is estimated, and compared with experimental assessment of the damage. The mechanical damage to the network caused by a bubble is probed using two independent approaches, a strain based method and an energy based method. Immunoflourescent fibrin staining is used to assess the region of damage experimentally.

  14. Full acoustic and thermal characterization of HIFU field in the presence of a ribcage model

    Science.gov (United States)

    Cao, Rui; Le, Nhan; Nabi, Ghulam; Huang, Zhihong

    2017-03-01

    In the treatment of abdominal organs using high intensity focused ultrasound (HIFU), the patient's ribs are in the pathway of the HIFU beams which could result in acoustic distortion, occasional skin burns and insufficient energy delivered to the target organs. To provide full characterization of HIFU field with the influence of ribcage, the ribcage phantom reconstructed from a patient's CT images was created by tissue mimicking materials and its effect on acoustic field was characterized. The effect of the ribcage on acoustic field has been provided in acoustic pressure distribution, acoustic power and focal temperature. Measurement result shows focus splitting with one main focus and two secondary intensity maxima. With the presence of ribcage phantom, the acoustic pressure was reduced by 48.3% and another two peak values were observed near the main focus, reduced by 65.0% and 71.7% respectively. The acoustic power was decreased by 47.5% to 52.5%. With these characterization results, the form of the focus, the acoustic power, acoustic pressure and temperature rise are provided before the transcostal HIFU treatment, which are significant to determine the energy delivery dose. In conclusion, this ribcage model and characterization technique will be useful for the further study in the abdominal HIFU treatment.

  15. Intercostal HIFU Treatment: A Tissue Phantom

    Science.gov (United States)

    Illing, Rowland O.; Kennedy, James E.; ter Haar, Gail R.

    2005-03-01

    High-intensity focused ultrasound (HIFU) when used clinically to treat liver and kidney tumours is often directed between the ribs. This paper details the construction of a tissue phantom, incorporating ribs, and its use to assess the clinical safety of HIFU exposures. The prefocal, acoustic side-lobes of the ultrasonic beam were studied with and without rib interference, and thermocouples used to assess in-situ temperature changes. The results show that there are implications in regards to the safety of clinical treatment, should the operator be unaware of the characteristics of the transducer being used.

  16. Sonablate-500TM Transrectal High-intensity Focused Ultrasound (HIFU) for Benign Prostatic Hyperplasia Patients

    Institute of Scientific and Technical Information of China (English)

    L(U) Jun; HU Weilie; WANG Wei; ZHANG Yuanfeng; CHEN Zhaoyang; YE Zhangqun

    2007-01-01

    To evaluate the safety and efficacy of transrectal high-intensity focused ultrasound (HIFU) in the treatment of benign prostatic hyperplasia (BPH), serial studies were conducted in 150 BPH pa- tients before and 30 min, 1, 2, 6 and 12 month(s) after Sonablate-500TM HIFU treatment. A sili- con-coated indwelling 16F latex catheter was placed during the determination of the therapy zone. Preoperative and postoperative evaluations were made by using the international prostate symptom score (IPSS), quality of life (QOL), uroflowmetric findings and transrectal ultrasound, and incidence of complications. The cystourethrography was done in 23 patients within 1 year postoperatively. The results showed that after HIFU treatment, IPSS and QOL scores were significantly decreased at 1, 2, 6 and 12 month(s) (P<0.01). Maximum urine flow rate (6.0 to 17.2 mL/s, P<0.01), PVR (75.0 to 30.3,P<0.01) and prostatic volume (65.0 to 38.1 mL, P<0.05) were significantly improved 12 months after the operation. Recurrent urinary retention (n=2) and urethrorectal fistula (n=1) occurred at the 15th postoperative day. The duration of the HIFU prostate ablation was 25-90 rain. The mean time for an indwelling catheter was 3-19 days. These data demonstrate that treatment of BPH with Sonab- late-500TM HIFU is safe and effective.

  17. HIFU as a Neoadjuvant Therapy in Cancer Treatment

    Science.gov (United States)

    Zhong, P.; Xing, F.; Huang, X.; Zhu, H.; Lo, H. W.; Zhong, X.; Pruitt, S.; Robertson, C.

    2011-09-01

    To broaden the application spectrum of HIFU in cancer therapy, we performed a pilot experiment to evaluate the potential of using HIFU as a neoadjuvant therapy prior to surgery. Mice bearing wild-type B16F10 melanoma inoculated subcutaneously were either untreated (control) or treated by HIFU, CPA-7 or HIFU+CPA-7 before surgical resection of the primary tumor two days after HIFU treatment. The animals were then followed for four weeks or up to the humane endpoint to determine local recurrence, distant metastasis, and survival rate. The results demonstrate that animals treated by HIFU+CPA-7 (which is a small molecule that suppresses STAT3 activity) had a significantly lower recurrence rate, and slower growth of the recurrent tumor, with concomitantly higher survival rate, followed by those treated with CPA-7 and HIFU, respectively. Immunological assays revealed that CPA-7 treatment could significantly lower STAT3, and subsequently, Treg activities. In particular, the combination of HIFU and CPA-7 can induce a much stronger anti-tumor immune response than HIFU or surgery alone, as assessed by CTL and IFN-γ secretion. Overall, our results suggest that HIFU in combination with immunotherapy strategies has the potential to be used as a neoadjuvant therapy to prime the host with a strong anti-tumor immune response before surgical resection of the primary tumor. This multimodality, combinational therapy has the potential to greatly broaden the range of HIFU applications in cancer therapy with lower tumor recurrence and improved survival rate.

  18. The Efficacy of High-Intensity Focused Ultrasound (HIFU) in Advanced Pancreatic Cancer

    Institute of Scientific and Technical Information of China (English)

    Bo Xie; Jiajun Ling; Weiming Zhang; Xueqin Huang; Jihua Zhen; Yanzhe Huang

    2008-01-01

    OBJECTIVE To observe the efficacy of high-intensity focused ultrasound (HIFU)in the treatment of late-stage pancreatic cancer.METHODS Sixteen patients with advanced pancreatic cancer received HIFU therapy.Evaluation of efficacy was made on the basis of changes in clinical symptoms and variations in the tumor echo and size.RESULTS Clinical symptoms such as pain were significantly alleviated,echo of the tumor was enhanced with B-US and the quality of life such as eating,sleeping and mental status was markedly improved;no serious complications were observed.CONCLUSION The use of HIFU in the treatment of advanced pancreatic cancer is feasible and safe.It is effective in killing the carcinoma cells and alleviaring pain.This technique may offer non-invasive therapy for the treatment of patients with late-stage pancreatic cancer.

  19. 组织声学特性对高强度聚焦超声温度场的影响%Effect of tissue acoustic properties on HIFU temperature field

    Institute of Scientific and Technical Information of China (English)

    张晓静; 张平; 朱元光; 孙武军; 菅喜岐; 李智华

    2010-01-01

    目的 数值仿真组织声学特性对高强度聚焦超声(HIFU)焦域处温度场的影响,为HIFU治疗安全性和可靠性提供理论依据.方法 以实测新鲜离体猪肝组织不同温度下的声速和衰减系数为依据,利用时域有限差分(FDTD)法数值仿真研究HIFU治疗过程中组织内声速、衰减系数的变化和温度场的分布,分析讨论声速和衰减系数变化对60 ℃以上可治疗区域大小、位置的影响.结果 随着照射时间的延长,焦域处肝组织温升增大,声速下降,声衰减系数增大.随着声速的变化,形成的可治疗区域变大,焦点位置向远离换能器方向移动;随着声衰减系数的变化,焦域大小和焦点位置几乎不变.结论 猪肝组织内声速的变化对可治疗焦域的位置和大小影响较大;声衰减系数的变化对焦域的影响较小.%Objective To improve the safety and reliability in high intensity focused ultrasound(HIFU)therapy, the effects of tissue acoustic properties on the high intensity focused ultrasound temperature field were investigated. Methods Based on the measured data of sound velocity and attenuation coefficient at different temperature, the variation of sound velocity and attenuation coefficient, and the temperature distribution in tissue during HIFU therapy was simulated using FDTD method. Moreover, the effects of the two variable acoustic parameters on the therapeutic region above 60 ℃ were evaluated. Results Tissue temperature raise, sound speed decreased and the attenuation coefficient increased in the focal region, along with the passage of the exposure time. Therapeutic region increased slightly and the focal point slightly moved away from the transducer when the sound velocity varied. There were negligible changes in the therapeutic region and the position of focal point when the attenuation coefficient changed alone in the study. Conclusion The variation of sound velocity can affect the size and location of the focal

  20. Tissue Erosion Using Shock Wave Heating and Millisecond Boiling in HIFU Fields

    Science.gov (United States)

    Canney, Michael S.; Khokhlova, Tatiana D.; Khokhlova, Vera A.; Bailey, Michael R.; Ha Hwang, Joo; Crum, Lawrence A.

    2010-03-01

    A wide variety of treatment protocols have been employed in high intensity focused ultrasound (HIFU) treatments, and the resulting bioeffects observed include both mechanical as well as thermal effects. In recent studies, there has been significant interest in generating purely mechanical damage using protocols with short, microsecond pulses. Tissue erosion effects have been attained by operating HIFU sources using short pulses of 10-20 cycles, low duty cycles (<1%), and pulse average intensities of greater than 20 kW/cm2. The goal of this work was to use a modified pulsing protocol, consisting of longer, millisecond-long pulses of ultrasound and to demonstrate that heating and rapid millisecond boiling from shock wave formation can be harnessed to induce controlled mechanical destruction of soft tissue. Experiments were performed in excised bovine liver and heart tissue using a 2-MHz transducer. Boiling activity was monitored during exposures using a high voltage probe in parallel with the HIFU source. In situ acoustic fields and heating rates were determined for exposures using a novel derating approach for nonlinear HIFU fields. Several different exposure protocols were used and included varying the duty cycle, pulse length, and power to the source. After exposures, the tissue was sectioned, and the gross lesion morphology was observed. Different types of lesions were induced in experiments that ranged from purely thermal to purely mechanical depending on the pulsing protocol used. Therefore, shock wave heating and millisecond boiling may be an effective method for reliably generating significant tissue erosion effects.

  1. Characterization of HIFU transducers designed for sonochemistry application: Acoustic streaming.

    Science.gov (United States)

    Hallez, L; Touyeras, F; Hihn, J-Y; Bailly, Y

    2016-03-01

    Cavitation distribution in a High Intensity Focused Ultrasound sonoreactors (HIFU) has been extensively described in the recent literature, including quantification by an optical method (Sonochemiluminescence SCL). The present paper provides complementary measurements through the study of acoustic streaming generated by the same kind of HIFU transducers. To this end, results of mass transfer measurements (electrodiffusional method) were compared to optical method ones (Particle Image Velocimetry). This last one was used in various configurations: with or without an electrode in the acoustic field in order to have the same perturbation of the wave propagation. Results show that the maximum velocity is not located at the focal but shifted near the transducer, and that this shift is greater for high powers. The two cavitation modes (stationary and moving bubbles) are greatly affect the hydrodynamic behavior of our sonoreactors: acoustic streaming and the fluid generated by bubble motion. The results obtained by electrochemical measurements show the same low hydrodynamic activity in the transducer vicinity, the same shift of the active focal toward the transducer, and the same absence of activity in the post-focal axial zone. The comparison with theoretical Eckart's velocities (acoustic streaming in non-cavitating media) confirms a very high activity at the "sonochemical focal", accounted for by wave distortion, which induced greater absorption coefficients. Moreover, the equivalent liquid velocities are one order of magnitude larger than the ones measured by PIV, confirming the enhancement of mass transfer by bubbles oscillation and collapse close to the surface, rather than from a pure streaming effect.

  2. Development of HIFU Therapy System for Lower Extremity Varicose Veins

    Science.gov (United States)

    Ota, Ryuhei; Suzuki, Jun; Yoshinaka, Kiyoshi; Deguchi, Juno; Takagi, Shu; Miyata, Tetsuro; Matsumoto, Yoichiro

    2009-04-01

    High-intensity focused ultrasound (HIFU) treatment utilizing microbubbles was investigated in the present study. It is known that microbubbles have the potential to enhance the heating effects of an ultrasound field. In this study, the heat accompanying microbubble oscillation was used to occlude varicose veins. Alteration of veins was observed after ultrasound irradiation. Veins were resected by stripping. In this study, two vein conditions were adopted during HIFU irradiation; non-compressed and compressed. Compressing the vein was expected to improve occlusion by rubbing the altered intima under compressed conditions. The frequency of the ultrasound was 1.7 MHz, the intensity at the focus was 2800 W/cm2, and the irradiation time was 20 s. In this study, the contrast agent Levovist® was chosen as a microbubble source, and the void fraction (ratio of total gas volume to liquid) in the vein was fixed at 10-5. Under non-compressed conditions, changes were observed only at the adventitia of the vein anterior wall. In contrast, under compressed conditions, changes were observed from the intima to the adventitia of both the anterior and posterior walls, and they were partly stuck together. In addition, more experiments with hematoxylin-eosin staining suggested that the changes in the vein were more substantial under the latter conditions. From these results, it was confirmed that the vein was occluded more easily with vein compression.

  3. Initial investigation of a novel noninvasive weight loss therapy using MRI-Guided high intensity focused ultrasound (MR-HIFU) of visceral fat.

    Science.gov (United States)

    Winter, Patrick M; Lanier, Matthew; Partanen, Ari; Dumoulin, Charles

    2016-07-01

    MRI-guided high intensity focused ultrasound (MR-HIFU) allows noninvasive heating of deep tissues. Specifically targeting visceral fat deposits with MR-HIFU could offer an effective therapy for reversing the development of obesity, diabetes, and metabolic syndrome. Overweight rats received either MR-HIFU of visceral fat, sham treatment, no treatment, or ex vivo temperature calibration. Conventional MR thermometry methods are not effective in fat tissue. Therefore, the T2 of fat was used to estimate heating in adipose tissue. HIFU treated rats lost 7.5% of their body weight 10 days after HIFU, compared with 1.9% weight loss in sham animals (P = 0.008) and 1.3% weight increase in untreated animals (P = 0.004). Additionally, the abdominal fat volume in treated animals decreased by 8.2 mL 7 days after treatment (P = 0.002). The T2 of fat at 1.5 Tesla increased by 3.3 ms per °C. The fat T2 was 103.3 ms before HIFU, but increased to 128.7 ms (P = 0.0005) after HIFU at 70 watts for 16 s and to 131.9 ms (P = 0.0005) after HIFU at 100 watts for 16 s. These experiments demonstrate that MR-HIFU of visceral fat could provide a safe, effective, and noninvasive weight loss therapy for combating obesity and the subsequent medical complications. Magn Reson Med 76:282-289, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  4. Initial Experience with the Extracorporeal HIFU Knife with 49 Patients: Japanese Experience

    Science.gov (United States)

    Ganaha, F.; Okuno, T.; Lee, C. O.; Shimizu, T.; Osako, K.; Oka, S.; Lee, K. H.; Chen, W. Z.; Zhu, H.; Park, S. H.; Qi, Z.; Shi, D.; Song, H. S.

    2005-03-01

    Forty nine patients with 63 tumours were treated with the Chongqing Haifu knife, as an adjunct to intra-arterial chemoinfusion. Treatment targets included breast (20 lesions), liver (16), bone (8), lymph-node (6), soft tissue (4), lung and pleura (4), pancreas (2), kidney (2) and adrenal gland (1). Follow-up contrast MRI was performed at 3 weeks to assess the effects of HIFU ablation. All cases completed the planned treatment. Of 25 lesions treated with the intention of complete tumour ablation, complete necrosis was obtained in 19 lesions (76%) including 4 secondary success cases. Among 32 lesions having partial and palliative treatment, tumour size was decreased in 6 lesions (21%), and good pain control was obtained in 6 out of 7 patients (86%). Skin injury was the most common complication after HIFU (16%), and was mostly a superficial dermal burn that did not necessitate any treatment. However, there was one patient with deep skin injury at an operation scar which resulted in skin perforation. Other adverse events included soft tissue swelling, prolonged fever, anorexia, persistent pain, shortness of the breath, sacroiliac joint fracture and prolonged diarrhoea. In our limited experience, superficial lesions (e.g. breast cancer, bone, soft tissue, lymph-node and pleural metastasis) appear to be good candidates for HIFU treatment. There appears to be a role for the HIFU knife in pain control for patients with bone metastasis and pancreatic cancer.

  5. An Ultrasound Image-Based Dynamic Fusion Modeling Method for Predicting the Quantitative Impact of In Vivo Liver Motion on Intraoperative HIFU Therapies: Investigations in a Porcine Model.

    Directory of Open Access Journals (Sweden)

    W Apoutou N'Djin

    Full Text Available Organ motion is a key component in the treatment of abdominal tumors by High Intensity Focused Ultrasound (HIFU, since it may influence the safety, efficacy and treatment time. Here we report the development in a porcine model of an Ultrasound (US image-based dynamic fusion modeling method for predicting the effect of in vivo motion on intraoperative HIFU treatments performed in the liver in conjunction with surgery. A speckle tracking method was used on US images to quantify in vivo liver motions occurring intraoperatively during breathing and apnea. A fusion modeling of HIFU treatments was implemented by merging dynamic in vivo motion data in a numerical modeling of HIFU treatments. Two HIFU strategies were studied: a spherical focusing delivering 49 juxtapositions of 5-second HIFU exposures and a toroidal focusing using 1 single 40-second HIFU exposure. Liver motions during breathing were spatially homogenous and could be approximated to a rigid motion mainly encountered in the cranial-caudal direction (f = 0.20 Hz, magnitude > 13 mm. Elastic liver motions due to cardiovascular activity, although negligible, were detectable near millimeter-wide sus-hepatic veins (f = 0.96 Hz, magnitude 75%. Fusion modeling predictions were preliminarily validated in vivo and showed the potential of using a long-duration toroidal HIFU exposure to accelerate the ablation process during breathing (from 0.5 to 6 cm3 · min(-1. To improve HIFU treatment control, dynamic fusion modeling may be interesting for assessing numerically focusing strategies and motion compensation techniques in more realistic conditions.

  6. Effects of N2 O on the content of FHb and ICAM-1 in HIFU treatment patients%氧化亚氮对HIFU治疗患者FHb及ICAM-1含量的影响

    Institute of Scientific and Technical Information of China (English)

    陈佳; 但伶; 田泽丹; 黄燕; 周瑜; 张昭莉

    2014-01-01

    Objective To observe the effect of nitrous oxide (N2O) on the content of serum free hemoglobin ,and intercellular adhesion molecule‐1 (ICAM‐1) of patients with HIFU Therapy ,and investigate its action of tissue damage mechanism .Methods 50 patients with primary liver cancer undergoing HIFU surgery (ASA Ⅰ - Ⅱ class) were randomly divided into control group (group C) and experimental group(group N) ,25 patients of each group .General anesthesia method was used in both two groups , group C was by total intravenous anesthesia ,group N was adopted intravenous‐inhalation anesthesia .both two groups was adopted the same anesthesia induction method .anesthesia maintain of group N was joined N2 O on the basis of group C .both two groups were draw blood from the radial artery at the points of before anesthesia (T1 ) ,before operation (T2 ) ,1 h (T3 ) ,2 h (T4 ) ,3 h (T5 ) after intraoperative ,and 24 h after operation (T6 ) ,peroxidase reaction test and double antibody sandwich ELISA method were a‐dopted to detect the content of Fhb value and ICAM‐1 ;ultrasonography system of HIFU therapeutic instrument was used to meas‐ure the abdominal wall thickness of patients before and after operation .Results The content of FHb and ICAM‐1 in serum were significantly increased after operation than before with the anesthesia time (P<0 .05);compared with group C ,group N increased obviously at the same point in time (P<0 .05);preoperative and postoperative abdominal wall thickness value of group N was in‐creased significantly (P< 0 .05) .Conclusion It may be connected with N2 O enhanced ultrasound cavitation effect that the body produces more FHb and ICAM‐1 of group N in HIFU treatment ,and induces abdominal wall skin markedly swollen .%目的:观察氧化亚氮(N2O)对高强度聚焦超声(HIFU)治疗患者血清游离血红蛋白(FHb)及细胞间黏附分子1(ICAM‐1)含量的影响,探讨其组织损伤的作用机制。方法将50

  7. Biological Effects of Ionizing Radiation

    Science.gov (United States)

    Ingram, M.; Mason, W. B.; Whipple, G. H.; Howland, J. W.

    1952-04-07

    This report presents a review of present knowledge and concepts of the biological effects of ionizing radiations. Among the topics discussed are the physical and chemical effects of ionizing radiation on biological systems, morphological and physiological changes observed in biological systems subjected to ionizing radiations, physiological changes in the intact animal, latent changes following exposure of biological systems to ionizing radiations, factors influencing the biological response to ionizing radiation, relative effects of various ionizing radiations, and biological dosimetry.

  8. Development of HIFU Treatment for Lower Extremity Varicose Veins

    Science.gov (United States)

    Senoo, Naohiko; Ushijima, Hiroyuki; Suzuki, Jun; Yoshinaka, Kiyoshi; Deguchi, Juno; Takagi, Shu; Miyata, Tetsuro; Matsumoto, Yoichiro

    2011-09-01

    High-intensity focused ultrasound (HIFU) has recently been developed as a noninvasive therapeutic method. In our study, a novel noninvasive therapy with HIFU was proposed for occlusion of lower extremity varicose veins. The temperature increase caused by HIFU is used to occlude varicose veins. Occluded veins became fibrotic, resulting in complete recovery. Our final goal is the medical application of HIFU treatment for varicose veins. In this study, we attempted to occlude the veins of rabbits. Prior to venous occlusion experiments, the area heated by HIFU was investigated using bovine serum albumin (BSA) gel, which denatures at >70 °C. The results indicate that the size of the heated area mainly depends on intensity at the focal point and the exposure time. A tendency was also seen for the heated area to extend toward the transducer with increasing exposure time. In animal experiments, skin burns during HIFU exposure represented a critical problem. We therefore examined the safe range of HIFU intensities in abdominal exposure experiments before conducting venous occlusion experiments. The ultrasound frequency was 1.7 MHz. Intensity at the focal point was 900 W/cm2, and the exposure time was 20 s. Rabbits underwent chemical depilation and echo gel was applied to the exposed skin to fill the boundary gap. Target veins were compressed during HIFU exposure to avoid thermal dissipation, and hyaluronan water solution was injected between the veins and skin to maintain the distance between the skin and veins at ≥5 mm. Veins were then exposed to HIFU and occluded. The capability of HIFU treatment to occlude lower extremity varicose veins was verified by the present study.

  9. Quantum Effects in Biology

    Science.gov (United States)

    Mohseni, Masoud; Omar, Yasser; Engel, Gregory S.; Plenio, Martin B.

    2014-08-01

    List of contributors; Preface; Part I. Introduction: 1. Quantum biology: introduction Graham R. Fleming and Gregory D. Scholes; 2. Open quantum system approaches to biological systems Alireza Shabani, Masoud Mohseni, Seogjoo Jang, Akihito Ishizaki, Martin Plenio, Patrick Rebentrost, Alàn Aspuru-Guzik, Jianshu Cao, Seth Lloyd and Robert Silbey; 3. Generalized Förster resonance energy transfer Seogjoo Jang, Hoda Hossein-Nejad and Gregory D. Scholes; 4. Multidimensional electronic spectroscopy Tomáš Mančal; Part II. Quantum Effects in Bacterial Photosynthetic Energy Transfer: 5. Structure, function, and quantum dynamics of pigment protein complexes Ioan Kosztin and Klaus Schulten; 6. Direct observation of quantum coherence Gregory S. Engel; 7. Environment-assisted quantum transport Masoud Mohseni, Alàn Aspuru-Guzik, Patrick Rebentrost, Alireza Shabani, Seth Lloyd, Susana F. Huelga and Martin B. Plenio; Part III. Quantum Effects in Higher Organisms and Applications: 8. Excitation energy transfer in higher plants Elisabet Romero, Vladimir I. Novoderezhkin and Rienk van Grondelle; 9. Electron transfer in proteins Spiros S. Skourtis; 10. A chemical compass for bird navigation Ilia A. Solov'yov, Thorsten Ritz, Klaus Schulten and Peter J. Hore; 11. Quantum biology of retinal Klaus Schulten and Shigehiko Hayashi; 12. Quantum vibrational effects on sense of smell A. M. Stoneham, L. Turin, J. C. Brookes and A. P. Horsfield; 13. A perspective on possible manifestations of entanglement in biological systems Hans J. Briegel and Sandu Popescu; 14. Design and applications of bio-inspired quantum materials Mohan Sarovar, Dörthe M. Eisele and K. Birgitta Whaley; 15. Coherent excitons in carbon nanotubes Leonas Valkunas and Darius Abramavicius; Glossary; References; Index.

  10. Modeling pressure distribution and heat in the body tissue and extract the relationship between them in order to improve treatment planning in HIFU

    CERN Document Server

    Hajian, Saeed Reza; Pouladian, Majid; Hemmasi, Gholam Reza

    2016-01-01

    In high intensity focused ultrasound (HIFU) systems using non-ionizing methods in cancer treatment, if the device is applied to the body externally, the HIFU beam can damage nearby healthy tissues and burn skin due to lack of knowledge about the viscoelastic properties of patient tissue and failure to consider the physical properties of tissue in treatment planning. Addressing this problem by using various methods, such as MRI or ultrasound, elastography can effectively measure visco-elastic properties of tissue and fits within the pattern of stimulation and total treatment planning. In this paper, in a linear path of HIFU propagation, and by considering the smallest part of the path, including voxel with three mechanical elements of mass, spring and damper, which represents the properties of viscoelasticity of tissue, by creating waves of HIFU in the wire environment of MATLAB mechanics and stimulating these elements, pressure and heat transfer due to stimulation in the hypothetical voxel was obtained. Throu...

  11. High-Intensity Focused Ultrasound (HIFU) Using Sonablate® Devices for the Treatment of Benign Prostatic Hyperplasia and Localized Prostate Cancer: 18-year experience

    Science.gov (United States)

    Uchida, Toyoaki

    2011-09-01

    From 1993 to 2010, we have treated 156 patients benign prostatic hyperplasia (BPH) and 1,052 patients localized prostate cancer high-intensity focused ultrasound (HIFU). Four different HIFU devices, SonablateR-200, SonablateR-500, SonablateR-500 version 4 and Sonablate® TCM, have been used for this study. Clinical outcome of HIFU for BPH did not show any superior effects to transurethral resection of the prostate, laser surgery or transurethral vapolization of the prostate. However, HIFU appears to be a safe and minimally invasive therapy for patients with localized prostate cancer, especially low- and intermediate-risk patients. The rate of clinical outcome has significantly improved over the years due to technical improvements in the device.

  12. Measurements of HIFU-induced Lesions in BSA Gel Phantoms for HIFU Treatment of Varicose Veins of Lower Extremity

    Science.gov (United States)

    Ushijima, Hiroyuki; Senoo, Naohiko; Suzuki, Jun; Ichiyanagi, Mitsuhisa; Yoshinaka, Kiyoshi; Deguchi, Juno; Takagi, Shu; Miyata, Tetsuro; Matsumoto, Yoichiro

    2011-09-01

    HIFU treatment has been developed for various diseases because of its minimal invasiveness, and we are now developing a HIFU treatment for varicose veins of the lower extremity. Previous studies have succeeded in occluding rabbit's veins with HIFU, but the success rate was low (about 10%). Failures were mainly caused by skin burns. When the heating lesion comes close to skin, the absorbed ultrasound energy may cause skin burns. Therefore, it is necessary to study the relationships between HIFU lesions and skin burns to improve the success rate. To visualize heating lesions from HIFU, we used tissue-mimicking BSA gel phantoms. We tried various concentrations of BSA in gels, and determined 14% BSA as the most suitable for phantoms for experiments. The attenuation coefficient of the gel was 0.73 dB/cm, and the denaturation temperature was 70 °C. We put the BSA gel phantom in a water tank in which the temperature was kept at 39 °C, and used HIFU exposures at various intensities and irradiation times. After irradiation, we measured the sizes and positions of HIFU-induced lesions, and the results indicate that the sizes of lesion become larger when the intensitiy rises or irradiation time becomes longer. Furthermore, when the intensity rises and irradiation time becomes longer, the heating lesions move closer to upper surface of the gel, which means skin easily gets burned. Thus we have investigated relationships between HIFU parameters and heated lesions that can be used for further research into HIFU treatment of varicose veins of the lower extremity.

  13. Magnetic Resonance-Guided High-Intensity Focused Ultrasound (MRgHIFU) for Treatment of Symptomatic Uterine Fibroids: An Economic Analysis

    Science.gov (United States)

    Babashov, V; Palimaka, S; Blackhouse, G; O'Reilly, D

    2015-01-01

    Background Uterine fibroids, or leiomyomas, are the most common benign tumours in women of childbearing age. Some women experience symptoms (e.g., heavy bleeding) that require aggressive forms of treatment such as uterine artery embolization (UAE), myomectomy, magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU), and even hysterectomy. It is important to note that hysterectomy is not appropriate for women who desire future childbearing. Objectives The objective of this analysis was to evaluate the cost-effectiveness and budgetary impact of implementing MRgHIFU as a treatment option for symptomatic uterine fibroids in premenopausal women for whom drugs have been ineffective. Review Methods We performed an original cost-effectiveness analysis to assess the long-term costs and effects of MRgHIFU compared with hysterectomy, myomectomy, and UAE as a strategy for treating symptomatic uterine fibroids in premenopausal women aged 40 to 51 years. We explored a number of scenarios, e.g., comparing MRgHIFU with uterine-preserving procedures only, considering MRgHIFU-eligible patients only, and eliminating UAE as a treatment option. In addition, we performed a one-year budget impact analysis, using data from Ontario administrative sources. Four scenarios were explored in the budgetary impact analysis: MRgHIFU funded at 2 centres MRgHIFU funded at 2 centres and replacing only uterine-preserving procedures MRgHIFU funded at 6 centres MRgHIFU funded at 6 centres and replacing only uterine-preserving procedures Analyses were conducted from the Ontario public payer perspective. Results The base case determined that the uterine artery embolization (UAE) treatment strategy was the cost-effective option at commonly accepted willingness-to-pay values. Compared with hysterectomy, UAE was calculated as having an incremental cost-effectiveness ratio (ICER) of $46,480 per quality-adjusted life-year (QALY) gained. The MRgHIFU strategy was extendedly dominated by a

  14. PREVENTION OF DYSURIA AFTER HIFU THERAPY FOR PROSTATE CANCER

    Directory of Open Access Journals (Sweden)

    A. Yu. Shestaev

    2014-07-01

    Full Text Available Objective: to identify factors for the development of dysuria and its prevention in patients with prostate cancer (PC after high-intensity focused ultrasound (HIFU therapy.Subjects and methods. In September 2008 to June 2013, the Clinic of Urology, S.M. Kirov Military Medical Academy, treated 98 patients, by performing HIFU sessions on an Ablatherm apparatus (EDAP, France. All the patients underwent transurethral resection of the prostate (TURP to reduce the volume of the ablated tissue. The patients were divided into 2 groups: 1 29 patients underwent TURP 3 days before HIFU therapy; 2 69 did this 1 month before major surgery. Each group was divided into 2 subgroups: 1 after ultrasound ablation, a urethral catheter was inserted for 10 days; 2 epicystostoma was applied, followed by its overlapping on day 3 postablation and spontaneous urination. The postoperative incidence of dysuria was estimated from subjective (complaints, voiding diary, and Inter-national Prostate Symptom Score and objective (uroflowmetry, small pelvic ultrasonography with determination of residual urine volume criteria.Results. In the patients who had undergone TURP one month before HIFU therapy, grades I–II urinary incontinence and urethral pros-tatic stricture occurred much less infrequently than in those who had undergone this maneuver 3 days prior to major surgery. Urinary in-continence and urethral prostatic stricture occurred 2-fold more frequently after TURP being carried out 3 days before HIFU therapy than after the urethral catheter being inserted. TURP performed one month before HIFU therapy showed no great difference in the incidence complications regardless of the type of bladder drainage.Conclusion. The short interval between TURP and HIFU therapy for PC increases the risk of postoperative dysuric events. The optimal time to perform TURP prior to HIFU therapy is 1 month.

  15. PREVENTION OF DYSURIA AFTER HIFU THERAPY FOR PROSTATE CANCER

    Directory of Open Access Journals (Sweden)

    A. Yu. Shestaev

    2014-01-01

    Full Text Available Objective: to identify factors for the development of dysuria and its prevention in patients with prostate cancer (PC after high-intensity focused ultrasound (HIFU therapy.Subjects and methods. In September 2008 to June 2013, the Clinic of Urology, S.M. Kirov Military Medical Academy, treated 98 patients, by performing HIFU sessions on an Ablatherm apparatus (EDAP, France. All the patients underwent transurethral resection of the prostate (TURP to reduce the volume of the ablated tissue. The patients were divided into 2 groups: 1 29 patients underwent TURP 3 days before HIFU therapy; 2 69 did this 1 month before major surgery. Each group was divided into 2 subgroups: 1 after ultrasound ablation, a urethral catheter was inserted for 10 days; 2 epicystostoma was applied, followed by its overlapping on day 3 postablation and spontaneous urination. The postoperative incidence of dysuria was estimated from subjective (complaints, voiding diary, and Inter-national Prostate Symptom Score and objective (uroflowmetry, small pelvic ultrasonography with determination of residual urine volume criteria.Results. In the patients who had undergone TURP one month before HIFU therapy, grades I–II urinary incontinence and urethral pros-tatic stricture occurred much less infrequently than in those who had undergone this maneuver 3 days prior to major surgery. Urinary in-continence and urethral prostatic stricture occurred 2-fold more frequently after TURP being carried out 3 days before HIFU therapy than after the urethral catheter being inserted. TURP performed one month before HIFU therapy showed no great difference in the incidence complications regardless of the type of bladder drainage.Conclusion. The short interval between TURP and HIFU therapy for PC increases the risk of postoperative dysuric events. The optimal time to perform TURP prior to HIFU therapy is 1 month.

  16. Beam localization in HIFU temperature measurements using thermocouples, with application to cooling by large blood vessels.

    Science.gov (United States)

    Dasgupta, Subhashish; Banerjee, Rupak K; Hariharan, Prasanna; Myers, Matthew R

    2011-02-01

    Experimental studies of thermal effects in high-intensity focused ultrasound (HIFU) procedures are often performed with the aid of fine wire thermocouples positioned within tissue phantoms. Thermocouple measurements are subject to several types of error which must be accounted for before reliable inferences can be made on the basis of the measurements. Thermocouple artifact due to viscous heating is one source of error. A second is the uncertainty regarding the position of the beam relative to the target location or the thermocouple junction, due to the error in positioning the beam at the junction. This paper presents a method for determining the location of the beam relative to a fixed pair of thermocouples. The localization technique reduces the uncertainty introduced by positioning errors associated with very narrow HIFU beams. The technique is presented in the context of an investigation into the effect of blood flow through large vessels on the efficacy of HIFU procedures targeted near the vessel. Application of the beam localization method allowed conclusions regarding the effects of blood flow to be drawn from previously inconclusive (because of localization uncertainties) data. Comparison of the position-adjusted transient temperature profiles for flow rates of 0 and 400ml/min showed that blood flow can reduce temperature elevations by more than 10%, when the HIFU focus is within a 2mm distance from the vessel wall. At acoustic power levels of 17.3 and 24.8W there is a 20- to 70-fold decrease in thermal dose due to the convective cooling effect of blood flow, implying a shrinkage in lesion size. The beam-localization technique also revealed the level of thermocouple artifact as a function of sonication time, providing investigators with an indication of the quality of thermocouple data for a given exposure time. The maximum artifact was found to be double the measured temperature rise, during initial few seconds of sonication.

  17. 高强度聚焦超声治疗晚期胰腺癌21例效果观察及护理%Observation on the effect of HIFU in the treatment of 21 cases of advanced pancreatic cancer and nursing care

    Institute of Scientific and Technical Information of China (English)

    徐亚玲; 李士红; 魏民

    2011-01-01

    Objective: To explore the effect of high intensity focused ultrasound ( HIFU ) therapy in the treatment of ad vancod pancreatic cancer and nursing methods. Methods: 36 patients were randomly divided into treatment group ( n = 21 ) and control group ( n = 15 ). The patients were treated with type FEP - BY02 HIFU tumor therapy machine in the treatment group and the patients in the control group received supportive therapy. The treatment effectiveness and safety were observed by comparing the clinical symptoms, laboratory test results, imaging changes, complications, etc. , between the two groups. Results: The pain was obviously relieved in 90.5 % ( 19/21 ) of the patients and CAI 9 -9 decreased in the treatment group; the treated local tumor tissues were evidently necrotic and the life time was significantly longer compared with the control group ( P < 0.05 ). Such com plications as skin buros, pancreatitis and gastrointestinal tract perforation did not occur in the treatment group. Conclusion: HI FU therapy can reduce the symptoms, improve quality of life and prolong the life time of the patients with advanced pancreatic cancer%目的:探讨高强度聚焦超声(HIFU)治疗晚期胰腺癌患者的疗效与护理方法.方法:将36例晚期胰腺癌患者随机分为治疗组21例和对照组15例,治疗组应用 FEP-BY02 型 HIFU 肿瘤治疗机治疗,对照组实施支持疗法.通过比较两组临床症状、实验室检查、影像学变化、并发症等情况,观察HIFU的治疗效果和安全性.结果:治疗组90.5% (19/21)的患者疼痛症状明显缓解,CA19-9降低,HIFU治疗区域肿瘤组织明显坏死,患者生存期较对照组明显延长(P<0.05);治疗组患者未发生皮肤烧伤、胰腺炎、胃肠道穿孔等并发症.结论:HIFU能减轻晚期胰腺癌患者症状,改善生活质量,延长生存期.

  18. Modelling of the acoustic field of a multi-element HIFU array scattered by human ribs

    Energy Technology Data Exchange (ETDEWEB)

    Gelat, Pierre [National Physical Laboratory, Hampton Road, Teddington TW11 0LW (United Kingdom); Ter Haar, Gail [Therapeutic Ultrasound Group, Physics Department, Institute of Cancer Research, Sutton SM2 5NG (United Kingdom); Saffari, Nader, E-mail: Pierre.Gelat@npl.co.uk [Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom)

    2011-09-07

    The efficacy of high-intensity focused ultrasound (HIFU) for the treatment of a range of different cancers, including those of the liver, prostate and breast, has been demonstrated. As a non-invasive focused therapy, HIFU offers considerable advantages over techniques such as chemotherapy and surgical resection in terms of reduced risk of harmful side effects. Despite this, there are a number of significant challenges which currently hinder its widespread clinical application. One of these challenges is the need to transmit sufficient energy through the rib cage to induce tissue necrosis in the required volume whilst minimizing the formation of side lobes. Multi-element random-phased arrays are currently showing great promise in overcoming the limitations of single-element transducers. Nevertheless, successful treatment of a patient with liver tumours requires a thorough understanding of the way in which the ultrasonic pressure field from a HIFU array is scattered by the rib cage. In order to address this, a boundary element approach based on a generalized minimal residual (GMRES) implementation of the Burton-Miller formulation was used in conjunction with phase conjugation techniques to focus the field of a 256-element random HIFU array behind human ribs at locations requiring intercostal and transcostal treatment. Simulations were carried out on a 3D mesh of quadratic pressure patches generated using CT scan anatomical data for adult ribs 9-12 on the right side. The methodology was validated on spherical and cylindrical scatterers. Field calculations were also carried out for idealized ribs, consisting of arrays of strip-like scatterers, demonstrating effects of splitting at the focus. This method has the advantage of fully accounting for the effect of scattering and diffraction in 3D under continuous wave excitation.

  19. Feasibility of monitoring HIFU prostate cancer therapy using elastography

    Science.gov (United States)

    Souchon, Remi; Chapelon, Jean Y.; Bertrand, Michel J.; Kallel, Faouzi; Ophir, Jonathan

    2001-05-01

    The objective of this study is to investigate the feasibility of elastographic monitoring of High Intensity Focused Ultrasound (HIFU) therapy of prostate cancer. Elastography is an imaging technique based on strain estimation in soft tissues under quasi-static compression. Since pathological tissues and HIFU-induced lesions exhibit different elastic properties than normal tissues, elastography is potentially able to achieve these goals. An ultrasound scanner was connected to a PC to acquire RF images. This setup is compatible with a HIFU device used for prostate cancer therapy by transrectal route. The therapy transducer and the biplane-imaging probe are covered with a balloon filled with a coupling liquid. Compression of the prostate is applied by inflating the balloon, while imaging sector scans of the prostate. In-vivo elastograms of the prostate were acquired before HIFU treatment. Problems inherent to in-vivo acquisitions are reported, such as undesired tangential displacements during the radial compression. This study shows the potential for in-vivo elastogram acquisition of HIFU-induced lesions in the human prostate.

  20. 高强度聚焦超声对离体兔眼晶状体组织形态和弹性变化的影响%Effect of HIFU on the histomorphology and elasticity change of crystalline lens in rabbit

    Institute of Scientific and Technical Information of China (English)

    孔俐; 杜之渝; 晏丕松; 黄正; 白晋; 张丹; 张玙; 龚晓波

    2012-01-01

    Objective: To explore the influence of high intensity focused ultrasound on the histology and elasticity change of crystalline lens in rabbit. Methods: 184 eyes were randomly divided into blank group and HIFU group. The blank group didn't give irradiation. The eyes of HIFU group was exposed to HIFU with the acoustic power of 1,2W respectively for 3s,5s,8s, 10s, 15s, 20s and 25s; the acoustic power of 3,4,5 W respectively for 3s, 5s, 8s, 10s and 15s. After irradiation eyes fixed for histology. Based on the studies by Fisher, the elastic deformation of the crystalline lens was determinated before and after rotating. Results: Histology observation:when energy was lesser, morphology of the irraditon area was regular like the droplet. Their morphology was irregular when the energy increased,seeing lots of cavitation hubble generated by cavitational mechanisms. The irradiation by HIFU could change the elasticity of lens. Multiple comparison showed that there were no significantly difference in the elastic deformation of lens between blank group, 1 W, 3 S and 15 S group, 2 W, 15 S group and 3 - 5 W, 8 S greup(P 〉 0.05) .For the remaining groups as compared with the blank group there we,re statistical differences(P 〈 0.05). Couclusions: HIFU irradiation in vitro rabbit lens can be affected their elasticity change,and in a certain energy cavitation effect could regain the flexibility of the lens.%目的:探讨不同治疗剂量高强度聚焦超声(high intensity focused ultrasound,HIFU)对兔眼晶状体组织形态和弹性变化的影响。方法:184只兔眼球随机分为空白组和HIFU组,空白组未给予HIFU辐照,HIFU组选取功率1、2W分别辐照时间3、5、8、10、15、20、25s;功率3,4、5W分别辐照时间3、5、8、10、15s;辐照完后进行组织学观察以及弹性变化检测。结果:当HIFU剂量较小时,组织学观察可见晶状体辐照区形态规则,呈水滴状;当剂量增大达到

  1. Quantum Effects in Biological Systems

    CERN Document Server

    2016-01-01

    Since the last decade the study of quantum mechanical phenomena in biological systems has become a vibrant field of research. Initially sparked by evidence of quantum effects in energy transport that is instrumental for photosynthesis, quantum biology asks the question of how methods and models from quantum theory can help us to understand fundamental mechanisms in living organisms. This approach entails a paradigm change challenging the related disciplines: The successful framework of quantum theory is taken out of its low-temperature, microscopic regimes and applied to hot and dense macroscopic environments, thereby extending the toolbox of biology and biochemistry at the same time. The Quantum Effects in Biological Systems conference is a platform for researchers from biology, chemistry and physics to present and discuss the latest developments in the field of quantum biology. After meetings in Lisbon (2009), Harvard (2010), Ulm (2011), Berkeley (2012), Vienna (2013), Singapore (2014) and Florence (2015),...

  2. Biological Effectiveness of Antiproton Annihilation

    DEFF Research Database (Denmark)

    Maggiore, C.; Agazaryan, N.; Bassler, N.;

    2004-01-01

    from the annihilation of antiprotons produce an increase in ‘‘biological dose’’ in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct measurement of the biological effects of antiproton annihilation. The background, description, and status...

  3. Biological Effects of Acoustic Cavitation

    Science.gov (United States)

    2007-11-02

    rectified diffusion. 56 III. STABLE CAVITATION A. Introduction There are manv areas associated with the biological effects of ultrasound in which the...used said as cavitation indicators. Further, if clinical ultrasound systems are found to be inducing cavitation , either stable or transient, it will...O BIOLOGICAL EFFECTS OF ACOUSTIC CAVITATION by Lawrence A. Crum -- Physical Acoustics Research Laboratory Department of Physics and Astronomy ’ CTE

  4. Biological effects of electromagnetic fields.

    Science.gov (United States)

    Macrì, M. A.; Di Luzio, Sr.; Di Luzio, S.

    2002-01-01

    Nowadays, concerns about hazards from electromagnetic fields represent an alarming source for human lives in technologically developed countries. We are surrounded by electromagnetic fields everywhere we spend our working hours, rest or recreational activities. The aim of this review is to summarize the biological effects due to these fields arising from power and transmission lines, electrical cable splices, electronic devices inside our homes and work-places, distribution networks and associated devices such as cellular telephones and wireless communication tower, etc. Special care has been reserved to study the biological effects of electromagnetic fields on cell lines of the mammalian immune system about which our research group has been working for several years.

  5. Biological effectiveness of antiproton annihilation

    CERN Document Server

    Holzscheiter, Michael H.; Bassler, Niels; Beyer, Gerd; De Marco, John J.; Doser, Michael; Ichioka, Toshiyasu; Iwamoto, Keisuke S.; Knudsen, Helge V.; Landua, Rolf; Maggiore, Carl; McBride, William H.; Møller, Søren Pape; Petersen, Jorgen; Smathers, James B.; Skarsgard, Lloyd D.; Solberg, Timothy D.; Uggerhøj, Ulrik I.; Withers, H.Rodney; Vranjes, Sanja; Wong, Michelle; Wouters, Bradly G.

    2004-01-01

    We describe an experiment designed to determine whether or not the densely ionizing particles emanating from the annihilation of antiprotons produce an increase in “biological dose” in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct measurement of the biological effects of antiproton annihilation. The experiment has been approved by the CERN Research Board for running at the CERN Antiproton Decelerator (AD) as AD-4/ACE (Antiproton Cell Experiment) and has begun data taking in June of 2003. The background, description and the current status of the experiment are given.

  6. Biological effectiveness of antiproton annihilation

    DEFF Research Database (Denmark)

    Holzscheiter, M.H.; Agazaryan, N.; Bassler, Niels

    2004-01-01

    We describe an experiment designed to determine whether or not the densely ionizing particles emanating from the annihilation of antiprotons produce an increase in ‘‘biological dose’’ in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct...... measurement of the biological effects of antiproton annihilation. The experiment has been approved by the CERN Research Board for running at the CERN Antiproton Decelerator (AD) as AD-4/ACE (Antiproton Cell Experiment) and has begun data taking in June of 2003. The background, description and the current...

  7. Immune System Modulation with LOFU And HIFU Treatment of Prostate Cancer

    Science.gov (United States)

    Guha, C.; Huagang, Z.; Chen, W.; Carlosn, R.; Sanghvi, N. T.

    2011-09-01

    High intensity focused ultrasound (HIFU) results in instantaneous coagulative tissue necrosis. In contrast, "low" energy focused ultrasound (LOFU) induces membrane perturbation while maintaining cell viability. This report explores the tumor immunomodulatory roles of LOFU and HIFU combination treatment. We hypothesized that administration of repeated cycles of LOFU, followed by HIFU would release tumor-derived peptide-heat shock protein complexes in the blood and induce systemic tumor-specific immune response that would enhance tumor control of both local and systemic disease.

  8. HIFU Hemostasis of Liver Injuries Enhanced by Ultrasound Contrast Agents

    Science.gov (United States)

    Zderic, Vesna; Vaezy, Shahram; Brayman, Andrew A.; Matula, Thomas J.; O'Keefe, Grant E.; Crum, Lawrence A.

    2005-03-01

    Our objective was to investigate whether High-Intensity Focused Ultrasound (HIFU) hemostasis can be achieved faster in the presence of ultrasound contrast agents (UCA). Incisions (3 cm long and 0.5 cm deep) were made in surgically exposed rabbit liver. Optison at a concentration of 0.18 ml/kg was injected into the mesenteric vein, immediately before the incision was made. The HIFU applicator (frequency of 5.5 MHz, and intensity of 3,700 W/cm2) was scanned manually over the incision (at an approximate rate of 1 mm/s) until hemostasis was achieved. The times to complete hemostasis were measured and normalized with the initial blood loss. The hemostasis times were 59±23 s in the presence of Optison and 70±23 s without Optison. The presence of Optison produced a 37% reduction in the normalized hemostasis times (phemostasis of internal organ injuries.

  9. Combination of the transurethral resection and prostate HIFU ablation at treatment of the localized cancer

    Directory of Open Access Journals (Sweden)

    Popkov V.M.

    2014-09-01

    26 patients were included into HIFU and 74 group in group of the combined treatment (TURP+HIFU. Selection criteria for HIFU ablation were the localized cancer of a prostate concerning which earlier it wasn't carried out treatments, and level of a PSA at the time of statement of the diagnosis 15 ng/ml. All patients corresponding to these by criteria, were considered as candidates for treatment and inclusion in the analysis. The nadir and stability of PSA, the histologic conclusion, IPSS, quality of life and complication were estimated at time of postoperative supervision. Results: Statistically significant influence of a combination TURP+HIFU for the term of transurethral drainage of a bladder (a median of 40 days against 7 days, incontience frequency (15.4% against 6.9%, infections of urinary ways (47.9% against 11.4% and IPSS change during the postoperative period (on the average 8.91 against 3.37 is noted. During the short period of supervision it wasn't observed considerable changes in relation to efficiency: in HIFU group the frequency of repeated sessions made 25%, in TUR/HIFU group 4%. Conclusion: HIFU therapy is modern, minimum invasive method of a cancer therapy of a prostate. The combination of a transurethral resection and HIFU ablation significantly reduces the frequency of the complications connected with treatment. Maintaining the patient after combined TURP and HIFU ablation is comparable with maintaining the patient after usual TURP.

  10. Thermal ablation of a confluent lesion in the porcine kidney with a clinically available MR-HIFU system

    Science.gov (United States)

    van Breugel, J. M. M.; de Greef, M.; Wijlemans, J. W.; Schubert, G.; van den Bosch, M. A. A. J.; Moonen, C. T. W.; Ries, M. G.

    2017-07-01

    The incidence of small renal masses (SRMs) sized  lesion in the kidney using respiratory-gated MR-HIFU under clinical conditions in a pre-clinical study and (ii) to evaluate the reproducibility of the MR-HIFU ablation strategy. Healthy pigs (n  =  10) under general anesthesia were positioned on a clinical MR-HIFU system with integrated cooling. A honeycomb pattern of seven overlapping ablation cells (4  ×  4  ×  10 mm3, 450 W, <30 s) was ablated successively in the cortex of the porcine kidney. Both MR thermometry and acoustic energy delivery were respiratory gated using a pencil beam navigator on the contralateral kidney. The non-perfused volume (NPV) was visualized after the last sonication by contrast-enhanced (CE) T 1-weighted MR (T 1 w) imaging. Cell viability staining was performed to visualize the extent of necrosis. Results: a median NPV of 0.62 ml was observed on CE-T 1 w images (IQR 0.58-1.57 ml, range 0.33-2.75 ml). Cell viability staining showed a median damaged volume of 0.59 ml (IQR 0.24-1.35 ml, range 0-4.1 ml). Overlooking of the false rib, shivering of the pig, and too large depth combined with a large heat-sink effect resulted in insufficient heating in 4 cases. The NPV and necrosed volume were confluent in all cases in which an ablated volume could be observed. Our results demonstrated the feasibility of creating a confluent volume of ablated kidney cortical tissue in vivo with MR-HIFU on a clinically available system using respiratory gating and near-field cooling and showed its reproducibility.

  11. Decavanadate effects in biological systems.

    Science.gov (United States)

    Aureliano, Manuel; Gândara, Ricardo M C

    2005-05-01

    Vanadium biological studies often disregarded the formation of decameric vanadate species known to interact, in vitro, with high-affinity with many proteins such as myosin and sarcoplasmic reticulum calcium pump and also to inhibit these biochemical systems involved in energy transduction. Moreover, very few in vivo animal studies involving vanadium consider the contribution of decavanadate to vanadium biological effects. Recently, it has been shown that an acute exposure to decavanadate but not to other vanadate oligomers induced oxidative stress and a different fate in vanadium intracellular accumulation. Several markers of oxidative stress analyzed on hepatic and cardiac tissue were monitored after in vivo effect of an acute exposure (12, 24 h and 7 days), to a sub-lethal concentration (5 mM; 1 mg/kg) of two vanadium solutions ("metavanadate" and "decavanadate"). It was observed that "decavanadate" promote different effects than other vanadate oligomers in catalase activity, glutathione content, lipid peroxidation, mitochondrial superoxide anion production and vanadium accumulation, whereas both solutions seem to equally depress reactive oxygen species (ROS) production as well as total intracellular reducing power. Vanadium is accumulated in mitochondria in particular when "decavanadate" is administered. These recent findings, that are now summarized, point out the decameric vanadate species contributions to in vivo and in vitro effects induced by vanadium in biological systems.

  12. First Experience Of Application Of High-Intensity Focused Ultrasonic Ablation (Hifu In Prostate Cancer Treatment

    Directory of Open Access Journals (Sweden)

    A.V. Stativko

    2009-12-01

    Full Text Available The scientific article points out that 40 sessions of HIFU prostate ablation have been performed for estimation of clinical efficiency. Average frequency of influences presents 628±164 impulses; average volume of tissues subjected to influence during one procedure is 33,8±16,3 smi (132 % of prostate volume; average operation time constitutes 150 minutes (from 90 to 200 minutes. During the operation no complications have been occurred. In the first days after the session of HIFU there was a peak of PSA increase and then during 1,5-3 months there was decrease to the lowest index. Minimal PSA level was reached in 10-12 weeks after treatment and it constituted from 0,04 till 1,1 ngml depending on the disease state. Reduction of prostate volume occurred in average from the 30th day of postoperative period and lasted for 6 months, reaching in average 50 % from initial volume. Postoperative period varied from 10 till 16 days and constituted in average 12±0,8 days. Thus application of high-intensity focused ultrasonic ablation allows treating successfully various stages of prostate cancer with minimal number of side-effects and makes possible the early estimation of treatment efficiency

  13. Quantum Effects in Biological Systems

    Science.gov (United States)

    Roy, Sisir

    2014-07-01

    The debates about the trivial and non-trivial effects in biological systems have drawn much attention during the last decade or so. What might these non-trivial sorts of quantum effects be? There is no consensus so far among the physicists and biologists regarding the meaning of "non-trivial quantum effects". However, there is no doubt about the implications of the challenging research into quantum effects relevant to biology such as coherent excitations of biomolecules and photosynthesis, quantum tunneling of protons, van der Waals forces, ultrafast dynamics through conical intersections, and phonon-assisted electron tunneling as the basis for our sense of smell, environment assisted transport of ions and entanglement in ion channels, role of quantum vacuum in consciousness. Several authors have discussed the non-trivial quantum effects and classified them into four broad categories: (a) Quantum life principle; (b) Quantum computing in the brain; (c) Quantum computing in genetics; and (d) Quantum consciousness. First, I will review the above developments. I will then discuss in detail the ion transport in the ion channel and the relevance of quantum theory in brain function. The ion transport in the ion channel plays a key role in information processing by the brain.

  14. HematoPorphyrin Monomethyl Ether polymer contrast agent for ultrasound/photoacoustic dual-modality imaging-guided synergistic high intensity focused ultrasound (HIFU) therapy

    Science.gov (United States)

    Yan, Sijing; LU, Min; Ding, Xiaoya; Chen, Fei; He, Xuemei; Xu, Chunyan; Zhou, Hang; Wang, Qi; Hao, Lan; Zou, Jianzhong

    2016-01-01

    This study is to prepare a hematoporphyrin monomethyl ether (HMME)-loaded poly(lactic-co-glycolic acid) (PLGA) microcapsules (HMME/PLGA), which could not only function as efficient contrast agent for ultrasound (US)/photoacoustic (PA) imaging, but also as a synergistic agent for high intensity focused ultrasound (HIFU) ablation. Sonosensitizer HMME nanoparticles were integrated into PLGA microcapsules with the double emulsion evaporation method. After characterization, the cell-killing and cell proliferation-inhibiting effects of HMME/PLGA microcapsules on ovarian cancer SKOV3 cells were assessed. The US/PA imaging-enhancing effects and synergistic effects on HIFU were evaluated both in vitro and in vivo. HMME/PLGA microcapsules were highly dispersed with well-defined spherical morphology (357 ± 0.72 nm in diameter, PDI = 0.932). Encapsulation efficiency and drug-loading efficiency were 58.33 ± 0.95% and 4.73 ± 0.15%, respectively. The HMME/PLGA microcapsules remarkably killed the SKOV3 cells and inhibited the cell proliferation, significantly enhanced the US/PA imaging results and greatly enhanced the HIFU ablation effects on ovarian cancer in nude mice by the HMME-mediated sono-dynamic chemistry therapy (SDT). HMME/PLGA microcapsules represent a potential multifunctional contrast agent for HIFU diagnosis and treatment, which might provide a novel strategy for the highly efficient imaging-guided non-invasive HIFU synergistic therapy for cancers by SDT in clinic. PMID:27535093

  15. HematoPorphyrin Monomethyl Ether polymer contrast agent for ultrasound/photoacoustic dual-modality imaging-guided synergistic high intensity focused ultrasound (HIFU) therapy

    Science.gov (United States)

    Yan, Sijing; Lu, Min; Ding, Xiaoya; Chen, Fei; He, Xuemei; Xu, Chunyan; Zhou, Hang; Wang, Qi; Hao, Lan; Zou, Jianzhong

    2016-08-01

    This study is to prepare a hematoporphyrin monomethyl ether (HMME)-loaded poly(lactic-co-glycolic acid) (PLGA) microcapsules (HMME/PLGA), which could not only function as efficient contrast agent for ultrasound (US)/photoacoustic (PA) imaging, but also as a synergistic agent for high intensity focused ultrasound (HIFU) ablation. Sonosensitizer HMME nanoparticles were integrated into PLGA microcapsules with the double emulsion evaporation method. After characterization, the cell-killing and cell proliferation-inhibiting effects of HMME/PLGA microcapsules on ovarian cancer SKOV3 cells were assessed. The US/PA imaging-enhancing effects and synergistic effects on HIFU were evaluated both in vitro and in vivo. HMME/PLGA microcapsules were highly dispersed with well-defined spherical morphology (357 ± 0.72 nm in diameter, PDI = 0.932). Encapsulation efficiency and drug-loading efficiency were 58.33 ± 0.95% and 4.73 ± 0.15%, respectively. The HMME/PLGA microcapsules remarkably killed the SKOV3 cells and inhibited the cell proliferation, significantly enhanced the US/PA imaging results and greatly enhanced the HIFU ablation effects on ovarian cancer in nude mice by the HMME-mediated sono-dynamic chemistry therapy (SDT). HMME/PLGA microcapsules represent a potential multifunctional contrast agent for HIFU diagnosis and treatment, which might provide a novel strategy for the highly efficient imaging-guided non-invasive HIFU synergistic therapy for cancers by SDT in clinic.

  16. Biological studies of radiation effects

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, J.H.

    1949-11-16

    This paper discusses procedures for research on biological effects of radiation, using mouse tissue: activation trace analysis including methods and proceedures for handling samples before during and after irradiation; methods and procedures for ion exchange study; method of separation and recovery of copper, iron, zinc, cobalt, pubidium and cesium. Also included are studies of trace elements with radioactive isotopes: the distribution of cobalt 60, zinc 65, and copper 64 in the cytoplasm and nuclei of normal mice and those with tumors. 16 figs., 2 tabs.

  17. In-office rapid volumetric ablation of uterine fibroids under ultrasound imaging guidance: Preclinical and early clinical experience with the Mirabilis transabdominal HIFU treatment system

    Science.gov (United States)

    Leal, José G. Garza; León, Ivan Hernandez; Sáenz, Lorena Castillo; Aguirre, Juan M. Aguilar; Lagos, Joel J. Islas; Parsons, Jessica E.; Darlington, Gregory P.; Lau, Michael P. H.

    2017-03-01

    Mirabilis Medica, Inc. (Bothell, WA, USA) has developed a high-intensity focused ultrasound (HIFU) system for producing rapid transabdominal volumetric ablation of uterine fibroids in an office-based setting. The Mirabilis HIFU Treatment System utilizes integrated ultrasound imaging guidance and short treatment times under 15 minutes. Treatment with the Mirabilis system is generally well tolerated using only oral analgesia without anesthesia or sedation. This paper summarizes certain technical aspects of the Mirabilis HIFU technology, the preclinical development process, and the results of the first in-human clinical study using the Mirabilis system. During preclinical studies, an in vivo transcutaneous porcine lower extremity model was used in a total of 180 adult swine to develop the HIFU treatment regimen parameters. Additionally, 108 excised human uteri with fibroids obtained from scheduled hysterectomies were treated in an ex vivo experimental setup and evaluated. These preclinical activities resulted in a HIFU treatment technique referred to as Mirabilis Shell Ablation, which enables rapid volumetric fibroid ablation by directing the HIFU energy to the outer perimeter of the target volume (the `shell') without insonating its core. This method results in efficient fibroid treatment through a synergistic combination of direct tissue ablation, cooperative heating effects, and indirect ischemic necrosis in the interior of the volume. After refining this technique and performing safety testing in the in vivo porcine model, a clinical pilot study was conducted to assess the initial safety and performance of the Mirabilis HIFU Treatment System for transabdominal treatment of uterine fibroids in eligible women who were scheduled to undergo hysterectomy following treatment with the device. A total of 37 women meeting certain eligibility criteria were treated at two clinical sites in Mexico. Twenty-nine (29) of these 37 women received only prophylactic sublingual

  18. 高强度聚焦超声(HIFU)肿瘤热消融技术的关键问题简析%Analysis of key problem of high intensity focused ultrasound (HIFU) thermal ablation technique

    Institute of Scientific and Technical Information of China (English)

    李发琪

    2011-01-01

    目的 1988年,王智彪萌发了用高强度聚焦超声(high intensity focused ultrasound,HIFU)从体外对体内肿瘤进行非侵入切除的灵感.在之后的10年中,他和他的团队在该领域提出了"生物学焦域"、"超声治疗剂量学"、"组织声环境"等概念.在实时超声监控、治疗系统优化、远程医疗系统、临床方案等方面突破了相应的关键技术壁垒.将HIFU治疗技术成功运用于外科治疗,在国际上积累了数量最多的临床病例.在该领域的设备研制、临床应用及若干基础研究方面走在了世界前列.%In 1988, Zhibiao Wang had an inspiration of ablating tumor in vivo non-invasively by high intensity focused ultrasound (HIFU). In the following 10 years, he and his team first proposed concepts such as "biological focal region", "ultrasound therapy dosimetry", "acoustic environment in tissue" and so on. They had broken down the key technical barriers in real-time ultrasound monitoring, treatment system optimization, telemedicine system, clinical protocols and other aspects, making HIFU therapy successfully applied to surgery and accumulated the largest number of clinical cases internationally. They have been playing a leading role around the world in equipment development, clinical application and some basic research in this field.

  19. A framework for the correction of slow physiological drifts during MR-guided HIFU therapies: Proof of concept

    Energy Technology Data Exchange (ETDEWEB)

    Zachiu, Cornel, E-mail: C.Zachiu@umcutrecht.nl; Moonen, Chrit; Ries, Mario [Imaging Division, UMC Utrecht, Heidelberglaan 100, Utrecht 3584 CX (Netherlands); Denis de Senneville, Baudouin [Imaging Division, UMC Utrecht, Heidelberglaan 100, Utrecht 3584 CX (Netherlands); Mathematical Institute of Bordeaux, University of Bordeaux, Talence Cedex 33405 (France)

    2015-07-15

    Purpose: While respiratory motion compensation for magnetic resonance (MR)-guided high intensity focused ultrasound (HIFU) interventions has been extensively studied, the influence of slow physiological motion due to, for example, peristaltic activity, has so far been largely neglected. During lengthy interventions, the magnitude of the latter can exceed acceptable therapeutic margins. The goal of the present study is to exploit the episodic workflow of these therapies to implement a motion correction strategy for slow varying drifts of the target area and organs at risk over the entire duration of the intervention. Methods: The therapeutic workflow of a MR-guided HIFU intervention is in practice often episodic: Bursts of energy delivery are interleaved with periods of inactivity, allowing the effects of the beam on healthy tissues to recede and/or during which the plan of the intervention is reoptimized. These periods usually last for at least several minutes. It is at this time scale that organ drifts due to slow physiological motion become significant. In order to capture these drifts, the authors propose the integration of 3D MR scans in the therapy workflow during the inactivity intervals. Displacements were estimated using an optical flow algorithm applied on the 3D acquired images. A preliminary study was conducted on ten healthy volunteers. For each volunteer, 3D MR images of the abdomen were acquired at regular intervals of 10 min over a total duration of 80 min. Motion analysis was restricted to the liver and kidneys. For validating the compatibility of the proposed motion correction strategy with the workflow of a MR-guided HIFU therapy, an in vivo experiment on a porcine liver was conducted. A volumetric HIFU ablation was completed over a time span of 2 h. A 3D image was acquired before the first sonication, as well as after each sonication. Results: Following the volunteer study, drifts larger than 8 mm for the liver and 5 mm for the kidneys prove that

  20. [Biological effect of wood dust].

    Science.gov (United States)

    Maciejewska, A; Wojtczak, J; Bielichowska-Cybula, G; Domańska, A; Dutkiewicz, J; Mołocznik, A

    1993-01-01

    The biological effect of exposure to wood dust depends on its composition and the content of microorganisms which are an inherent element of the dust. The irritant and allergic effects of wood dust have been recognised for a long time. The allergic effect is caused by the wood dust of subtropical trees, e.g. western red cedar (Thuja plicata), redwood (Sequoia sempervirens), obeche (Triplochiton scleroxylon), cocabolla (Dalbergia retusa) and others. Trees growing in the European climate such as: larch (Larix), walnut (Juglans regia), oak (Quercus), beech (Fagus), pine (Pinus) cause a little less pronounced allergic effect. Occupational exposure to irritative or allergic wood dust may lead to bronchial asthma, rhinitis, alveolitis allergica, DDTS (Organic dust toxic syndrome), bronchitis, allergic dermatitis, conjunctivitis. An increased risk of adenocarcinoma of the sinonasal cavity is an important and serious problem associated with occupational exposure to wood dust. Adenocarcinoma constitutes about half of the total number of cancers induced by wood dust. An increased incidence of the squamous cell cancers can also be observed. The highest risk of cancer applies to workers of the furniture industry, particularly those dealing with machine wood processing, cabinet making and carpentry. The cancer of the upper respiratory tract develops after exposure to many kinds of wood dust. However, the wood dust of oak and beech seems to be most carcinogenic. It is assumed that exposure to wood dust can cause an increased incidence of other cancers, especially lung cancer and Hodgkin's disease. The adverse effects of microorganisms, mainly mould fungi and their metabolic products are manifested by alveolitis allergica and ODTS. These microorganisms can induce aspergillomycosis, bronchial asthma, rhinitis and allergic dermatitis.

  1. Biological effects of drilling wastes

    Energy Technology Data Exchange (ETDEWEB)

    Cranford, P. J. [Department of Fisheries and Oceans, Dartmouth, NS (Canada). Bedford Inst. of Oceanography

    2000-07-01

    An argument is made for the point of view that economic realities require that a sustainable fishery must co-exist with the offshore petroleum industry, and therefore to sustain the fishery comprehensive studies are needed to identify and minimize the impact of operational drilling wastes on fishery resources. Moreover, laboratory and field studies indicate that operational drilling platforms impact on fisheries at great distances, therefore studies should not be limited to the immediate vicinity of drilling sites. Studies on long-term exposure of resident organisms to low level contaminants and the chronic lethal and sublethal biological effects of production drilling wastes must be conducted under environmentally relevant conditions to ensure the validity of the results. Studies at the Bedford Institute of Oceanography on sea scallops (Placopecten magellanicus) shows them to be highly sensitive to impacts from drilling wastes. Results of these studies, integrated with toxicity data and information on the distribution and transport of drilling wastes have been used by regulatory agencies and industrial interests to develop scientifically sound and justifiable regulations. They also led to the development of practical, sensitive and cost-effective technologies that use resident resource species to detect environmental impacts at offshore production sites. 1 fig.

  2. Research on the positioning problem in HIFU surgery platform application

    Institute of Scientific and Technical Information of China (English)

    XIANG Lin-qing; GAO Xue-guan; XU Jian-bo; MA Pei-sun

    2006-01-01

    For describing the positioning process of High Intensity Focused Ultrasound (HIFU) Surgery Platform in the application in tumor treatment, a simplified representation of the shape and location of the positioning target tumor in the workspace of the platform by the Positioning Volume Ellipsoid is designed; and the Nearest Neighbor Search method is used to find the closest center point of the simplified ellipsoid tumor model in a selected patient body surface point set determined by the motion parameter of the platform. By the query result the goal positioning path configuration and an intermediate positioning path configuration for the positioning motion are determined for the positioning motion planning. Three new criterions using distance change between Positioning Volume Ellipsoid and the Ultrasound Focus Ellipsoid are proposed to evaluate the result of the whole positioning procedure.

  3. Whole Body Bone Scan Findings after High Intensity Focused Ultrasound (HIFU) Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Ye Young; O, Joo Hyun; Sohn, Hyung Sun; Choi, Eun Kyoung; Yoo, Ik Dong; Oh, Jin Kyoung; Han, Eun Ji; Jung, Seung Eun; Kim, Sung Hoon [The Catholic Univ. of Korea, Seoul (Korea, Republic of)

    2011-12-15

    This study aims to examine the findings of {sup 99mT}c diphosphonate bone scans in cancer patients with a history of HIFU treatment. Bone scan images of patients with a history of HIFU treatment for primary of metastatic cancer from January 2006 to July 2010 were retrospectively reviewed. Cases of primary bone tumor or HIFU treatment reaching only the superficial soft tissue layer were excluded. Bone scan images of 62 patients (26 female, 36 male; mean age 57{+-}9 years) were studied. HIFU treatment was performed in the liver (n=40), pancreas (n=40), pancreas (n=16), and breast (n=6). Mean interval time between HIFU treatment and bone scan was 106{+-}105 days (range: 1-572 days). Of 62 scans, 43 showed diffusely decreased uptake of bone within the path of HIFU treatment: antero axillary and/or posterior arcs of right 5th to 11th ribs in 34 cases after treatment of hepatic lesions; anterior arcs of 2nd to 5th ribs in 5 cases after treatment for breast tumors; and posterior arcs of left 9th to 11th ribs or thoraco lumbar vertebrae in 4 cases after treatment for pancreas tumor. Of 20 patients who had bone scans more than twice, five showed recovered uptake of the radiotracer in the involved ribs in the follow up bone scan. Of 62 bone scans in patients with a history of HIFU treatment for primary of metastatic cancer, 69% presented diffusely decreased uptake in the bone in the path of HIFU treatment.

  4. TU-B-210-02: MRg HIFU - Advanced Approaches for Ablation and Hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Moonen, C. [University Medical Center Utrecht (Netherlands)

    2015-06-15

    MR guided focused ultrasound (MRgFUS), or alternatively high-intensity focused ultrasound (MRgHIFU), is approved for thermal ablative treatment of uterine fibroids and pain palliation in bone metastases. Ablation of malignant tumors is under active investigation in sites such as breast, prostate, brain, liver, kidney, pancreas, and soft tissue. Hyperthermia therapy with MRgFUS is also feasible, and may be used in conjunction with radiotherapy and for local targeted drug delivery. MRI allows in situ target definition and provides continuous temperature monitoring and subsequent thermal dose mapping during HIFU. Although MRgHIFU can be very precise, treatment of mobile organs is challenging and advanced techniques are required because of artifacts in MR temperature mapping, the need for intercostal firing, and need for gated HIFU or tracking of the lesion in real time. The first invited talk, “MR guided Focused Ultrasound Treatment of Tumors in Bone and Soft Tissue”, will summarize the treatment protocol and review results from treatment of bone tumors. In addition, efforts to extend this technology to treat both benign and malignant soft tissue tumors of the extremities will be presented. The second invited talk, “MRI guided High Intensity Focused Ultrasound – Advanced Approaches for Ablation and Hyperthermia”, will provide an overview of techniques that are in or near clinical trials for thermal ablation and hyperthermia, with an emphasis of applications in abdominal organs and breast, including methods for MRTI and tracking targets in moving organs. Learning Objectives: Learn background on devices and techniques for MR guided HIFU for cancer therapy Understand issues and current status of clinical MRg HIFU Understand strategies for compensating for organ movement during MRgHIFU Understand strategies for strategies for delivering hyperthermia with MRgHIFU CM - research collaboration with Philips.

  5. TU-B-210-01: MRg HIFU - Bone and Soft Tissue Tumor Ablation

    Energy Technology Data Exchange (ETDEWEB)

    Ghanouni, P. [Stanford University (United States)

    2015-06-15

    MR guided focused ultrasound (MRgFUS), or alternatively high-intensity focused ultrasound (MRgHIFU), is approved for thermal ablative treatment of uterine fibroids and pain palliation in bone metastases. Ablation of malignant tumors is under active investigation in sites such as breast, prostate, brain, liver, kidney, pancreas, and soft tissue. Hyperthermia therapy with MRgFUS is also feasible, and may be used in conjunction with radiotherapy and for local targeted drug delivery. MRI allows in situ target definition and provides continuous temperature monitoring and subsequent thermal dose mapping during HIFU. Although MRgHIFU can be very precise, treatment of mobile organs is challenging and advanced techniques are required because of artifacts in MR temperature mapping, the need for intercostal firing, and need for gated HIFU or tracking of the lesion in real time. The first invited talk, “MR guided Focused Ultrasound Treatment of Tumors in Bone and Soft Tissue”, will summarize the treatment protocol and review results from treatment of bone tumors. In addition, efforts to extend this technology to treat both benign and malignant soft tissue tumors of the extremities will be presented. The second invited talk, “MRI guided High Intensity Focused Ultrasound – Advanced Approaches for Ablation and Hyperthermia”, will provide an overview of techniques that are in or near clinical trials for thermal ablation and hyperthermia, with an emphasis of applications in abdominal organs and breast, including methods for MRTI and tracking targets in moving organs. Learning Objectives: Learn background on devices and techniques for MR guided HIFU for cancer therapy Understand issues and current status of clinical MRg HIFU Understand strategies for compensating for organ movement during MRgHIFU Understand strategies for strategies for delivering hyperthermia with MRgHIFU CM - research collaboration with Philips.

  6. Biological effects of high LET radiations

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Masami [Nagasaki Univ. (Japan). Faculty of Pharmaceutical Sciences

    1997-03-01

    Biological effect of radiation is different by a kind of it greatly. Heavy ions were generally more effective in cell inactivation, chromosome aberration induction, mutation induction and neoplastic cell transformation induction than {gamma}-rays in SHE cells. (author)

  7. Correlation Effects in Biological Networks

    Directory of Open Access Journals (Sweden)

    A.A. Bagdasaryan

    2012-06-01

    Full Text Available Review of the complex network theory is presented and classification of such networks in accordance with the main statistical characteristics is considered. For the adjacency matrix of a real neural network the shortest distances for each pair of nodes as well as the node degree distribution and cluster coefficients are calculated. Comparison of the main statistical parameters with the random network is performed, and based on this, the conclusions about the correlation phenomena in biological system are made.

  8. MR thermometry analysis program for laser- or high-intensity focused ultrasound (HIFU)-induced heating at a clinical MR scanner

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Ju; Jeong, Ki Young; Oh, Seung Jae; Park, Eun Hae; Lee, Young Han; Suh, Jin Suck [Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Dae Hong [National Cancer Center, Goyang (Korea, Republic of)

    2014-12-15

    Magnetic resonance (MR) thermometry is a noninvasive method for monitoring local temperature change during thermal therapy. In this study, a MR temperature analysis program was established for a laser with gold nanorods (GNRs) and high-intensity focused ultrasound (HIFU)-induced heating MR thermometry. The MR temperature map was reconstructed using the water proton resonance frequency (PRF) method. The temperature-sensitive phase difference was acquired by using complex number subtraction instead of direct phase subtraction in order to avoid another phase unwrapping process. A temperature map-analyzing program was developed and implemented in IDL (Interactive Data Language) for effective temperature monitoring. This one program was applied to two different heating devices at a clinical MR scanner. All images were acquired with the fast spoiled gradient echo (fSPGR) pulse sequence on a 3.0 T GE Discovery MR750 scanner with an 8-channel knee array coil or with a home-built small surface coil. The analyzed temperature values were confirmed by using values simultaneously measured with an optical temperature probe (R{sup 2} = 0.996). The temperature change in small samples induced by a laser or by HIFU was analyzed by using a raw data, that consisted of complex numbers. This study shows that our MR thermometry analysis program can be used for thermal therapy study with a laser or HIFU at a clinical MR scanner. It can also be applied to temperature monitoring for any other thermal therapy based on the PRF method.

  9. Effect of biological characteristics of different types of uterine fibroids, as assessed with T2-weighted magnetic resonance imaging, on ultrasound-guided high-intensity focused ultrasound ablation.

    Science.gov (United States)

    Zhao, Wen-Peng; Chen, Jin-Yun; Chen, Wen-Zhi

    2015-02-01

    The aims of this study were to assess the effects of the biological characteristics of different types of uterine fibroids, as assessed with T2-weighted magnetic resonance imaging (MRI), on ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation. Thirty-five patients with 39 symptomatic uterine fibroids who underwent myomectomy or hysterectomy were enrolled. Before surgery, the uterine fibroids were subdivided into hypo-intense, iso-intense, heterogeneous hyper-intense and homogeneous hyper-intense categories based on signal intensity on T2-weighted MRI. Tissue density and moisture content were determined in post-operative samples and normal uterine tissue, the isolated uterine fibroids were subjected to USgHIFU, and the extent of ablation was measured using triphenyltetrazolium chloride. Hematoxylin and eosin staining and sirius red staining were undertaken to investigate the organizational structure of the uterine fibroids. Estrogen and progesterone receptor expression was assayed via immunohistochemical staining. The mean diameter of uterine fibroids was 6.9 ± 2.8 cm. For all uterine fibroids, the average density and moisture content were 10.7 ± 0.7 mg/mL and 75.7 ± 2.4%, respectively; and for the homogeneous hyper-intense fibroids, 10.3 ± 0.5 mg/mL and 76.6 ± 2.3%. The latter subgroup had lower density and higher moisture content compared with the other subgroups. After USgHIFU treatment, the extent of ablation of the hyper-intense fibroids was 102.7 ± 42.1 mm(2), which was significantly less than those of the hypo-intense and heterogeneous hyper-intense fibroids. Hematoxylin and eosin staining and sirius red staining revealed that the homogeneous hyper-intense fibroids had sparse collagen fibers and abundant cells. Immunohistochemistry results revealed that estrogen and progesterone receptors were highly expressed in the homogeneous hyper-intense fibroids. This study revealed that lower density, higher moisture content, sparse collagen

  10. Biological effects of thyroid hormones

    Directory of Open Access Journals (Sweden)

    T. S. Saatov

    2013-12-01

    Full Text Available The article presents the findings from the study on multifunctional effects of thyroid hormones in relation to normal and malignantly transformed tissues and cells. Both “rapid” and «slow» effects of thyroid hormones including calorigenic effects and effects over adenylate cyclase – cAMP system have been described. Thyroxin (Т4 has been established capable to inhibit proliferation and to induce apoptosis of cells carrying Т4 receptors on their membranes as well as to change course of metabolic processes under its effect. Spectrum of Т4 targets is quite broad to include not only cells of hormone-producing organs, to name those of the breast and the colon, but also other types of cells to name melanin-containing ones; Т4 effects resulting in reconstruction of presentation of regulatory proteins on the cell membrane surface to ultimately activate the process of cell apoptosis. Our findings help determine alternative paths for hormonal regulation of cell proliferation and apoptosis of cells of hormone-dependent tumors, breast cancer, in particular, upon impossibility to regulate the processes by conventional methods. This facilitates understanding mechanisms for activation of signal system of the breast cancer’s cells by hormones upon changes in expression of receptors on the cells’ surface, making possible development of novel strategy for replacement therapy of hormone-dependent tumors upon low efficacy of drug therapy.

  11. A new experimental study on noninvasive thermometry in HIFU

    Institute of Scientific and Technical Information of China (English)

    侯珍秀; 徐祯祥; 金长善

    2002-01-01

    The measurement of temperature at the heated point is very important and difficult for the treatmentof tumor using HIFU( High intensity focused ultrasound). According to the theory that the gray scale value va-ries with the ultrasound transmitting through different tissues at different temperatures, a set of experiment e-quipment was designed to describe the temperature field in tissues by using the characteristics of the ultrasonicimage, and an experiment was carried out with fresh liver and muscle tissues of pigs in a temperature arrange of26 ℃ to 64 ℃. The statistical curve of the experiment demonstrates: ( 1 ) The gray scales vary in accordancewith the changes in the temperature of tissue and it is feasible to measure the temperature at the heated point bymaking use of the gray scale variations; (2) Non-linearity is the characteristics of temperature changes and thegray scale of tissues at different temperature phases. Moreover, the gray scale varies from up to down phase atthe same temperature phase; ( 3 ) The gray scale for the same temperature range varies with different tissues. Anexperimented formula is proposed for the measurement of fresh liver and muscle tissues of pigs.

  12. An Ultrasound Imaging-Guided Robotic HIFU Ablation Experimental System and Accuracy Evaluations

    Directory of Open Access Journals (Sweden)

    Chih Yu An

    2017-01-01

    Full Text Available In recent years, noninvasive thermal treatment by using high-intensity focused ultrasound (HIFU has high potential in tumor treatment. The goal of this research is to develop an ultrasound imaging-guided robotic HIFU ablation system for tumor treatment. The system integrates the technologies of ultrasound image-assisted guidance, robotic positioning control, and HIFU treatment planning. With the assistance of ultrasound image guidance technology, the tumor size and location can be determined from ultrasound images as well as the robotic arm can be controlled to position the HIFU transducer to focus on the target tumor. After the development of the system, several experiments were conducted to measure the positioning accuracy of this system. The results show that the average positioning error is 1.01 mm with a standard deviation 0.34, and HIFU ablation accuracy is 1.32 mm with a standard deviation 0.58, which means this system is confirmed with its possibility and accuracy.

  13. High-Intensity Focused Ultrasound (Hifu) Treatment For Thyroid Nodules: Experimental And First Clinical Studies

    Science.gov (United States)

    Esnault, Olivier; Franc, Brigitte; Leenhardt, Laurence; Rouxel, Agnès; Ménégaux, Fabrice; Lacoste, François

    2007-05-01

    OBJECTIVE: Thyroid nodules are common and can only be removed by surgery. High-intensity focused ultrasound (HIFU) could be a possible minimally invasive alternative treatment. The aim of this study was to assess the feasibility of using HIFU to precisely ablate thyroid nodules without affecting neighbouring structures. METHODS: HIFU was generated by a 3-MHz spherical piezocomposite transducer moved across the target in a stepwise fashion. In a first clinical study 25 patients had their nodules treated with HIFU 2 weeks prior to planned thyroidectomy, using increasing energy. The last patients received a local anesthesia. The lesions were assessed by the pathologist. RESULTS: The histological lesions were clearly visible in most of the fully treated patients, particularly those who received higher energy. Superficial and reversible skin blisters were observed in 7 patients. The design of the treatment head was subsequently modified to eliminate such risk. CONCLUSION: The patient trials confirmed the precision of the targeting and set the energy levels for safe thyroid nodule ablation with HIFU. Further study is needed to assess nodule's changes at longer follow-up.

  14. PSA nadir as a predictive factor for biochemical disease-free survival and overall survival following whole-gland salvage HIFU following radiotherapy failure

    NARCIS (Netherlands)

    Shah, T T; Peters, M; Kanthabalan, A; McCartan, N; Fatola, Y; van der Voort van Zyp, J; van Vulpen, M; Freeman, A; Moore, C M; Arya, M; Emberton, M; Ahmed, H U

    2016-01-01

    BACKGROUND: Treatment options for radio-recurrent prostate cancer are either androgen-deprivation therapy or salvage prostatectomy. Whole-gland high-intensity focussed ultrasound (HIFU) might have a role in this setting. METHODS: An independent HIFU registry collated consecutive cases of HIFU. Betwe

  15. Biological effects of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, B.G. [SENES Oak Ridge Inc., Oak Ridge, TN (United States); Theodorakis, C.W.; Shugart, L.R. [Oak Ridge National Lab., Oak Ridge, TN (United States). Environmental Sciences Division

    1996-12-31

    Natural populations have always been exposed to background levels of ionizing radiation; however, with the event of the nuclear age, studies about the effects of higher-than-background levels of ionizing radiation on individuals or populations of organisms became important. Originally, concern was focused on survival after large, acute radiation doses, and numerous studies document the somatic and genetic effects of acute ionizing radiation. However, there is a growing realization that chronic long-term exposure to higher-than-background levels of environmental radiation is more likely than is large acute exposure. Less than 10% of the literature on ionizing radiation effects deals with chronic long-term effects, and very few studies involve natural populations. In 1977, mosquito fish, Gambusia affinis, were experimentally introduced into a 0,45 ha, decommissioned, radioactive waste pond where the measured dose at the sediment-water interface was 1,150 rad/year. One year later, the fecundity of the population had not changed significantly. Eighteen years later, studies of the fish showed an inverse correlation between DNA strand breakage and fecundity in the contaminated pond. More recent studies have provided evidence that genetic diversity of the fish has increased in the contaminated site. These fish also have a greater prevalence of certain DNA banding patterns. Individuals displaying these banding patterns have a higher fecundity and lower degree of DNA strand breakage than individuals with less common banding patterns. Gambusia affinis has apparently adapted to the high background radiation, successfully surviving for approximately 50 generations. 31 refs, 5 figs.

  16. Acute effects of sono-activated photocatalytic titanium dioxide nanoparticles on oral squamous cell carcinoma.

    Science.gov (United States)

    Moosavi Nejad, S; Takahashi, Hiromasa; Hosseini, Hamid; Watanabe, Akiko; Endo, Hitomi; Narihira, Kyoichi; Kikuta, Toshihiro; Tachibana, Katsuro

    2016-09-01

    Sonodynamic therapy (SDT) is a new treatment modality using ultrasound to activate certain chemical sensitizers for cancer therapy. In this study, effects of high intensity focused ultrasound (HIFU) combined with photocatalytic titanium dioxide (TiO2) nanoparticles on human oral squamous cell line HSC-2 were investigated. Viability of HSC-2 cells after 0, 0.1, 1, or 3s of HIFU irradiation with 20, 32, 55 and 73Wcm(-2) intensities in the presence or absence of TiO2 was measured immediately after the exposures in vitro. Immediate effects of HIFU (3s, 73Wcm(-2)) combined with TiO2 on solid tumors were also examined by histological study. Cytotoxic effect of HIFU+TiO2in vitro was significantly higher than that of TiO2 or HIFU alone with the tendency to increase for higher HIFU intensity, duration, and TiO2 concentration in the suspension. In vivo results showed significant necrosis and tissue damage in HIFU and HIFU+TiO2 treated samples. However, penetration of TiO2 nanoparticles into the cell cytoplasm was only observed in HIFU+TiO2 treated tissues. In this study, our findings provide a rational basis for the development of an effective HIFU based sonodynamic activation method. This approach offers an attractive non-invasive therapy technique for oral cancer in future.

  17. BIOLOGICAL EFFECTS ON THE SOURCE OF GEONEUTRINOS

    DEFF Research Database (Denmark)

    Sleep, Norman H.; Bird, Dennis K.; Rosing, Minik T.

    2013-01-01

    its bulk earth value of similar to 4; Pb isotope measurements on mantle-derived rocks yield low Th/U values, effectively averaged over geological time. The physics of the modern biological process is complicated, but the net effect is that much of the U in the mantle comes from subducted marine...

  18. Contrast Agent Ultrasonography before and after HIFU Treatment of Parathyroid Glands

    Science.gov (United States)

    Kovatcheva, Roussanka; Arnaud, Françoise; Lacoste, François

    2010-03-01

    OBJECTIVES: To observe changes in the parathyroid tissue treated by extracorporeal HIFU. MATERIAL AND METHODS: 5 patients were treated for primary hyperparathyroidism by thermally ablating enlarged parathyroid glands using an external HIFU applicator. The treated glands were visualized with B-Mode and contrast enhanced ultrasonography (CEUS) before, 1 week and 4 weeks post HIFU. Serum iPTH, calcium, and phosphorus levels were monitored before and after the treatment. RESULTS: The initial results showed a correlation between contrast agent uptake of treated parathyroid tissue, the reduction of volume of the gland and the decrease of iPTH levels. CONCLUSIONS These results show it is possible to use CEUS to monitor the thermal ablation of parathyroid glands.

  19. Characterization of HIFU ablation using DNA fragmentation labeling as apoptosis stain

    Science.gov (United States)

    Anquez, Jeremie; Corréas, Jean-Michel; Pau, Bernard; Lacoste, François; Yon, Sylvain

    2012-11-01

    The goal of this work was to compare modalities to precisely quantify the extent of thermally induced lesions: gross pathology vs. histopathology vs. devascularization. Liver areas of 14 rabbits were targeted with HIFU and RF ablations in an acute study. Contrast enhanced computorized tomography (CE-CT) scan images were acquired two hours after HIFU and RF treatment to obtain the devascularized volumes of the livers. The animals were then euthanized and deep frozen. The livers were sliced and each slice was photographed and stacked yielding a volume of gross pathology. The volume VGP of the HIFU lesions were derived. The area AGP of the lesions were computed on a particular slice. The lesions were segmented as hypo intense (devascularized) regions on CE-CT images and their volumes VC were computed. The ratios VC/VGP were computed for all the HIFU lesions on all the 14 subjects with a mean value of 1.2. Histology was performed on the livers using Hematoxyline Eosine Staining (HES) and DNA Fragmentation labeling (TUNEL® technology) which characterizes apoptosis. Apoptotic regions of area AT were segmented on the images stained by TUNEL®. No necrosis was identified on the HES data. While TUNEL® did not mark the cores of the RF lesions as apoptotic, the periphery of HIFU and RF lesions was always recognized with TUNEL® as apoptotic. The ratio AGP/AT was computed. The mean value was 0.95 and 0.25 for HIFU and RF lesions respectively. These findings show that the devascularized territory seen on CE-CT scan coincide with the coagulated territories seen with gross pathology. Those actually correspond to cells in apoptosis. It is confirmed that HES stain does not show necrosis 2 hours after thermal ablation. TUNEL® technology for DNA fragmentation labeling appears as a useful marker for thermally induced acute lesions in the liver.

  20. Biological Effects of Low-Dose Exposure

    CERN Document Server

    Komochkov, M M

    2000-01-01

    On the basis of the two-protection reaction model an analysis of stochastic radiobiological effects of low-dose exposure of different biological objects has been carried out. The stochastic effects are the results published in the last decade: epidemiological studies of human cancer mortality, the yield of thymocyte apoptosis of mice and different types of chromosomal aberrations. The results of the analysis show that as dependent upon the nature of biological object, spontanous effect, exposure conditions and radiation type one or another form dose - effect relationship is realized: downwards concave, near to linear and upwards concave with the effect of hormesis included. This result testifies to the incomplete conformity of studied effects of 1990 ICRP recomendations based on the linear no-threshold hypothesis about dose - effect relationship. Because of this the methodology of radiation risk estimation recomended by ICRP needs more precisian and such quantity as collective dose ought to be classified into...

  1. Biological Effect of Magnetic Field in Mice

    Institute of Scientific and Technical Information of China (English)

    Zhao-Wei ZENG

    2005-01-01

    Objective: To study the biological effect of magnetic field in mice bodies. Method: With a piece of permanent magnet embeded in mice bodies beside the femoral artery and vein to measure the electrophoretic velocity(um/s). Result: The magnetic field in mice bodies on the experiment group that the electrophoretic velocity is faster more than control and free group.Conclusion:The magnetic field in animal's body can raise the negative electric charges on the surface of erythrocyte to improve the microcirculation, this is the biological effect of magnetic field.

  2. TU-EF-210-01: HIFU, Drug Delivery, and Immunotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Ferrara, K. [University of California - Davis (United States)

    2015-06-15

    The use of therapeutic ultrasound to provide targeted therapy is an active research area that has a broad application scope. The invited talks in this session will address currently implemented strategies and protocols for both hyperthermia and ablation applications using therapeutic ultrasound. The role of both ultrasound and MRI in the monitoring and assessment of these therapies will be explored in both pre-clinical and clinical applications. Katherine Ferrara: High Intensity Focused Ultrasound, Drug Delivery, and Immunotherapy Rajiv Chopra: Translating Localized Doxorubicin Delivery to Pediatric Oncology using MRI-guided HIFU Elisa Konofagou: Real-time Ablation Monitoring and Lesion Quantification using Harmonic Motion Imaging Keyvan Farahani: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy Learning Objectives: Understand the role of ultrasound in localized drug delivery and the effects of immunotherapy when used in conjunction with ultrasound therapy. Understand potential targeted drug delivery clinical applications including pediatric oncology. Understand the technical requirements for performing targeted drug delivery. Understand how radiation-force approaches can be used to both monitor and assess high intensity focused ultrasound ablation therapy. Understand the role of AAPM task groups in ultrasound imaging and therapies. Chopra: Funding from Cancer Prevention and Research Initiative of Texas (CPRIT), Award R1308 Evelyn and M.R. Hudson Foundation; Research Support from Research Contract with Philips Healthcare; COI are Co-founder of FUS Instruments Inc Ferrara: Supported by NIH, UCDavis and California (CIRM and BHCE) Farahani: In-kind research support from Philips Healthcare.

  3. A New Model of Thermal Propagation in Human Tissue by Using HIFU Application

    CERN Document Server

    Hajian, Saeed Reza; Pouladian, Majid; Hemmasi, Gholam Reza

    2016-01-01

    In outside the body HIFU treatment that focused ultrasound beams hit severely with cancer tissue layer especially the soft one, at the time of passage of the body different layers as long as they want to reach tumor, put their own way components under mechanical and even thermal influence and they can cause skin lesions. To reduce this effect a specific mechanical model can be used that means body tissue is considered as a mechanical model, it is affected when passing sound mechanical waves through it and each layer has an average heat. Gradually sound intensity decreases through every layer passage, finally in one direction a decreased intensity sound reach tumor tissue. If sound propagated directions increase, countless waves with decreased intensity are gathered upon the tumor tissue that causes a lot of heat focus on tumor tissue. Depending on the kind and mechanical properties of the tissue, intensity of each sound wave when it passes through tissue can be controlled to reduce damages outside the tumor t...

  4. A Pulsatile Flow Phantom for Image-Guided HIFU Hemostasis of Blood Vessels

    Science.gov (United States)

    Greaby, Robyn; Vaezy, Shahram

    2005-03-01

    A pulsatile flow phantom for studying ultrasound image-guided acoustic hemostasis in a controlled environment has been developed. An ex vivo porcine carotid artery was attached to the phantom and embedded in a visually and ultrasonically transparent gel. Heparinized porcine blood was pumped through the phantom. Power-Doppler and B-mode ultrasound were used to remotely target the HIFU focus to the site of a needle puncture. In nine trials, complete hemostasis was achieved after an average HIFU application of 55 +/- 34 seconds. The vessels remained patent after treatment. With this phantom, it will be possible to do controlled studies of ultrasound image-guided acoustic hemostasis.

  5. Biological effects of electric fields: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, L.E.; Phillips, R.D.

    1983-11-01

    An overview of the literature suggests tha electric-field exposure is an environmental agent/influence of relatively low potential toxicity to biological systems. Generally, many of the biological effects which have been reported are quite subtle and differences between exposed and unexposed subjects may be masked by normal biological variations. However, several recent reports indicate possibly more serious consequences from chronic exposure, emphasizing the need for more research in epidemiology and laboratory experiments. This paper presents a cursory overview of investigations on the biological consequences of exposure to ELF electromagnetic fields. Three important topics are discussed, including: 1) the general methodology of exposure experiments, including those elements which are critical for definitive studies in biological systems; 2) a brief discussion of epidemiological and clinical studies conducted to date; and 3) a somewhat more extensive examination of animal experiments representing major areas of investigation (behavior, biological rhythms, nervous and endocrine systems, bone growth and repair, cardiovascular system and blood chemistry, immunology, reproduction, growth and development mortality and pathology, cellular and membrane studies, and mutagenesis). A discussion of current concepts, possible mechanisms and future directions of research is presented. 110 references.

  6. Estimation of Biological Effects of Tritium.

    Science.gov (United States)

    Umata, Toshiyuki

    Nuclear fusion technology is expected to create new energy in the future. However, nuclear fusion requires a large amount of tritium as a fuel, leading to concern about the exposure of radiation workers to tritium beta radiation. Furthermore, countermeasures for tritium-polluted water produced in decommissioning of the reactor at Fukushima Daiichi Nuclear Power Station may potentially cause health problems in radiation workers. Although, internal exposure to tritium at a low dose/low dose rate can be assumed, biological effect of tritium exposure is not negligible, because tritiated water (HTO) intake to the body via the mouth/inhalation/skin would lead to homogeneous distribution throughout the whole body. Furthermore, organically-bound tritium (OBT) stays in the body as parts of the molecules that comprise living organisms resulting in long-term exposure, and the chemical form of tritium should be considered. To evaluate the biological effect of tritium, the effect should be compared with that of other radiation types. Many studies have examined the relative biological effectiveness (RBE) of tritium. Hence, we report the RBE, which was obtained with radiation carcinogenesis classified as a stochastic effect, and serves as a reference for cancer risk. We also introduce the outline of the tritium experiment and the principle of a recently developed animal experimental system using transgenic mouse to detect the biological influence of radiation exposure at a low dose/low dose rate.

  7. Biological effectiveness of neutrons: Research needs

    Energy Technology Data Exchange (ETDEWEB)

    Casarett, G.W.; Braby, L.A.; Broerse, J.J.; Elkind, M.M.; Goodhead, D.T.; Oleinick, N.L.

    1994-02-01

    The goal of this report was to provide a conceptual plan for a research program that would provide a basis for determining more precisely the biological effectiveness of neutron radiation with emphasis on endpoints relevant to the protection of human health. This report presents the findings of the experts for seven particular categories of scientific information on neutron biological effectiveness. Chapter 2 examines the radiobiological mechanisms underlying the assumptions used to estimate human risk from neutrons and other radiations. Chapter 3 discusses the qualitative and quantitative models used to organize and evaluate experimental observations and to provide extrapolations where direct observations cannot be made. Chapter 4 discusses the physical principles governing the interaction of radiation with biological systems and the importance of accurate dosimetry in evaluating radiation risk and reducing the uncertainty in the biological data. Chapter 5 deals with the chemical and molecular changes underlying cellular responses and the LET dependence of these changes. Chapter 6, in turn, discusses those cellular and genetic changes which lead to mutation or neoplastic transformation. Chapters 7 and 8 examine deterministic and stochastic effects, respectively, and the data required for the prediction of such effects at different organizational levels and for the extrapolation from experimental results in animals to risks for man. Gaps and uncertainties in this data are examined relative to data required for establishing radiation protection standards for neutrons and procedures for the effective and safe use of neutron and other high-LET radiation therapy.

  8. Lunar biological effects and the magnetosphere.

    Science.gov (United States)

    Bevington, Michael

    2015-12-01

    The debate about how far the Moon causes biological effects has continued for two millennia. Pliny the Elder argued for lunar power "penetrating all things", including plants, fish, animals and humans. He also linked the Moon with tides, confirmed mathematically by Newton. A review of modern studies of biological effects, especially from plants and animals, confirms the pervasive nature of this lunar force. However calculations from physics and other arguments refute the supposed mechanisms of gravity and light. Recent space exploration allows a new approach with evidence of electromagnetic fields associated with the Earth's magnetotail at full moon during the night, and similar, but more limited, effects from the Moon's wake on the magnetosphere at new moon during the day. The disturbance of the magnetotail is perhaps shown by measurements of electric fields of up to 16V/m compared with the usual effects on some sensitive organisms. Similar intensities found in sferics, geomagnetic storms, aurora disturbance, sensations of a 'presence' and pre-seismic electromagnetic radiation are known to affect animals and 10-20% of the human population. There is now evidence for mechanisms such as calcium flux, melatonin disruption, magnetite and cryptochromes. Both environmental and receptor variations explain confounding factors and inconsistencies in the evidence. Electromagnetic effects might also account for some evolutionary changes. Further research on lunar biological effects, such as acute myocardial infarction, could help the development of strategies to reduce adverse effects for people sensitive to geomagnetic disturbance. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. II. Biological studies of radiation effects

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, J.H.

    1948-05-24

    With the completion of the 184 inch cyclotron in Berkeley and the successful construction of a deflector system, it was possible to bring the 190 Mev deuteron and the 380 Mev alpha beams out into the air and to begin a study of the effects of high-energy deuteron beams by direct irradiation of biological specimens. The direct biological use of deuteron beams was attempted earlier in Berkeley by Marshak, MacLeish, and Walker in 1940. These and other investigators have been aware for some time of the potential usefulness of high energy particle beams for radio-biological studies and their suitability for biological investigations. R.R. Wilson advanced the idea of using fast proton beams to deliver radiation and intervening tissues. R.E. Zirkle pointed out that such particle beams may be focused or screened until a cross-section of the beam is small enough to study effects of irradiation under the microscope on single cells or on parts of single cells. This article gives an overview of the radiological use of high energy deuteron beams, including the following topics: potential uses of high energy particle beams; experiments on the physical properties of the beam; lethal effect of the deuteron beam on mice.

  10. [Biological effects of electromagnetic fields (author's transl)].

    Science.gov (United States)

    Bernhardt, J

    1979-08-01

    This résumé deals with thermal and nonthermal effects of electromagnetic fields on man. In consideration of two aspects a limitation is necessary. Firstly, there will be discussed only direct and immediate influences on biological cells and tissues, secondly, the treatment is limited to such phenomena, for which biophysical aproximations, based on experimental data, could be developed. Hazards for the human being may occur only by thermal effects within the microwave range. Regarding frequencies below approximately 30 kHz, excitation processes cannot be excluded in exceptional cases. Thermal effects are predominant, between 30 kHz and 100 kHz, before excitations can appear. Furthermore, by comparing the electrically and magnetically induced currents with the naturally flowing currents in man caused by the brain's and heart's electrical activity, a "lower boundaryline" was estimated. Regarding electric or magnetic field strengths undercutting this boundary-line, direct effects on the central nervous system may be excluded; other mechanisms should be responsible for demonstrated biological effects. The paper closes referring to some reports--presently discussed--on experimental findings of biological effects, which are observed as a result of the influence of electromagnetic fields of small field strengths.

  11. Significant skin burns may occur with the use of a water balloon in HIFU treatment

    Science.gov (United States)

    Ritchie, Robert; Collin, Jamie; Wu, Feng; Coussios, Constantin; Leslie, Tom; Cranston, David

    2012-10-01

    HIFU is a minimally-invasive therapy suitable for treating selected intra-abdominal tumors. Treatment is safe although skin burns may occur due to pre-focal heating. HIFU treatment of a renal transplant tumor located in the left lower abdomen was undertaken in our centre. Treatment was performed prone, requiring displacement of the abdominal wall away from the treatment field using a water balloon, constructed of natural rubber latex and filled with degassed water. Intra-operatively, ultrasound imaging and physical examination of the skin directly over the focal region was normal. Immediately post-operative, a full-thickness skin burn was evident at the periphery of the balloon location, outside the expected HIFU path. Three possibilities may account for this complication. Firstly, the water balloon may have acted as a lens, focusing the HIFU to a neo-focus off axis. Secondly, air bubbles may have been entrapped between the balloon and the skin, causing heating at the interface. Finally, heating of the isolated water within the balloon may have been sufficient to cause burning. In this case, the placement of a water balloon caused a significant skin burn. Care should be taken in their use as burns, situated off axis, may occur even if the overlying skin appears normal.

  12. A study of three-dimensional tumor figure creating and treatment trail in HIFU

    Institute of Scientific and Technical Information of China (English)

    HOU zhen-xiu; ZHAO Yong-ping; CHEN Xin-liang; CHEN Shi-zhe; JIN Chang-shan

    2006-01-01

    This paper introduces a method in which a series of parallel B-ultrasonic tumor section images is recombined into a three-dimensional picture in HIFU (High Intensity Focus Ultrasonic) therapy. The experiments show that the recombining three-dimensional tumor is anastomose with the trim size, that the method is usable and accurate in the operation. It has a certain consulting value.

  13. A new HIFU probe for the treatment of the superficial venous insufficiency and varicose veins

    Science.gov (United States)

    Pichardo, Samuel; Curiel, Laura; Milleret, René; Pichot, Olivier; Lacoste, François; Chapelon, Jean-Yves

    2006-05-01

    A previous work showed the feasibility of inducing a localized partial shrinkage of venous tissues with High Intensity Focused Ultrasound (HIFU). A partial shrinkage of the vein wall is proposed to correct the valvular dysfunction on the saphenous vein that is responsible of the superficial venous insufficiency and varicose veins. In the present study, a new real-time imaging HIFU probe is presented which is suited for this type of treatment. The probe is composed of two HIFU elements that focus sound uniformly over a line of 7 mm-length. Geometry of the HIFU elements was calculated by numerical optimization and allows positioning of the focal line 15 mm in-depth from the skin. The probe is compatible with commercial imaging devices used currently in vascular medicine. Once coupled with an imaging probe, the imaging system shows the central perpendicular plan to the focal line. A validation of the compatibility with a commercial ultrasound imaging system was achieved using a precise model fabricated by stereo-lithography. Construction of the probe is underway.

  14. The Biological Effects of Bilirubin Photoisomers.

    Science.gov (United States)

    Jasprova, Jana; Dal Ben, Matteo; Vianello, Eleonora; Goncharova, Iryna; Urbanova, Marie; Vyroubalova, Karolina; Gazzin, Silvia; Tiribelli, Claudio; Sticha, Martin; Cerna, Marcela; Vitek, Libor

    2016-01-01

    Although phototherapy was introduced as early as 1950's, the potential biological effects of bilirubin photoisomers (PI) generated during phototherapy remain unclear. The aim of our study was to isolate bilirubin PI in their pure forms and to assess their biological effects in vitro. The three major bilirubin PI (ZE- and EZ-bilirubin and Z-lumirubin) were prepared by photo-irradiation of unconjugated bilirubin. The individual photoproducts were chromatographically separated (TLC, HPLC), and their identities verified by mass spectrometry. The role of Z-lumirubin (the principle bilirubin PI) on the dissociation of bilirubin from albumin was tested by several methods: peroxidase, fluorescence quenching, and circular dichroism. The biological effects of major bilirubin PI (cell viability, expression of selected genes, cell cycle progression) were tested on the SH-SY5Y human neuroblastoma cell line. Lumirubin was found to have a binding site on human serum albumin, in the subdomain IB (or at a close distance to it); and thus, different from that of bilirubin. Its binding constant to albumin was much lower when compared with bilirubin, and lumirubin did not affect the level of unbound bilirubin (Bf). Compared to unconjugated bilirubin, bilirubin PI did not have any effect on either SH-SY5Y cell viability, the expression of genes involved in bilirubin metabolism or cell cycle progression, nor in modulation of the cell cycle phase. The principle bilirubin PI do not interfere with bilirubin albumin binding, and do not exert any toxic effect on human neuroblastoma cells.

  15. Photoacoustic detection and optical spectroscopy of high-intensity focused ultrasound-induced thermal lesions in biologic tissue

    Energy Technology Data Exchange (ETDEWEB)

    Alhamami, Mosa; Kolios, Michael C.; Tavakkoli, Jahan, E-mail: jtavakkoli@ryerson.ca [Department of Physics, Ryerson University, 350 Victoria Street, Toronto, Ontario M5B 2K3 (Canada)

    2014-05-15

    Purpose: The aims of this study are: (a) to investigate the capability of photoacoustic (PA) method in detecting high-intensity focused ultrasound (HIFU) treatments in muscle tissuesin vitro; and (b) to determine the optical properties of HIFU-treated and native tissues in order to assist in the interpretation of the observed contrast in PA detection of HIFU treatments. Methods: A single-element, spherically concaved HIFU transducer with a centre frequency of 1 MHz was utilized to create thermal lesions in chicken breast tissuesin vitro. To investigate the detectability of HIFU treatments photoacoustically, PA detection was performed at 720 and 845 nm on seven HIFU-treated tissue samples. Within each tissue sample, PA signals were acquired from 22 locations equally divided between two regions of interest within two volumes in tissue – a HIFU-treated volume and an untreated volume. Optical spectroscopy was then carried out on 10 HIFU-treated chicken breast specimens in the wavelength range of 500–900 nm, in 1-nm increments, using a spectrophotometer with an integrating sphere attachment. The authors’ optical spectroscopy raw data (total transmittance and diffuse reflectance) were used to obtain the optical absorption and reduced scattering coefficients of HIFU-induced thermal lesions and native tissues by employing the inverse adding-doubling method. The aforementioned interaction coefficients were subsequently used to calculate the effective attenuation coefficient and light penetration depth of HIFU-treated and native tissues in the wavelength range of 500–900 nm. Results: HIFU-treated tissues produced greater PA signals than native tissues at 720 and 845 nm. At 720 nm, the averaged ratio of the peak-to-peak PA signal amplitude of HIFU-treated tissue to that of native tissue was 3.68 ± 0.25 (mean ± standard error of the mean). At 845 nm, the averaged ratio of the peak-to-peak PA signal amplitude of HIFU-treated tissue to that of native tissue was 3.75

  16. Evidence for a new mechanism behind HIFU-triggered release from liposomes.

    Science.gov (United States)

    Oerlemans, Chris; Deckers, Roel; Storm, Gert; Hennink, Wim E; Nijsen, J Frank W

    2013-06-28

    A promising approach for local drug delivery is high-intensity focused ultrasound (HIFU)-triggered release of drugs from stimuli-responsive nanoparticles such as liposomes. The aim of this study was to investigate whether another release mechanism is involved with HIFU-triggered release from liposomes beside cavitation and temperature. Furthermore, it was studied whether this new release mechanism allows the release of lipophilic compounds. Therefore, both a lipophilic (Nile red) and a hydrophilic (fluorescein) compound were loaded into thermosensitive (TSL) or non-thermosensitive liposomes (NTSL) and the liposomes were subjected both to continuous wave (CW)- and pulsed wave (PW)-HIFU. The mean liposome size varied from 97 to 139 nm with a polydispersity index (PDI)≤0.06 for the different formulations. The Tm of the phospholipid bilayer of the TSL was around 42°C. Approximately 80% of fluorescein was released within 15 min from TSL at temperatures≥42°C. In contrast, no fluorescein release from NTSL and NR release from both TSL and NTSL was observed at temperatures up to 60 °C. CW-HIFU exposure of TSL resulted in rapid temperature elevation up to 52°C and subsequently almost quantitative fluorescein release. Fluorescein release from NTSL was also substantial (~64% after 16 min at 20 W). Surprisingly, CW-HIFU exposure (20W for 16 min) resulted in the release of NR from TSL (~66% of the loaded amount), and this was even higher from NTSL (~78%). PW-HIFU exposure did not result in temperatures above the Tm of TSL. However, nearly 85% of fluorescein was released from TSL after 32 min at 20W of PW-HIFU exposure, whereas the release from NTSL was around 27%. Interestingly, NR release from NTSL was~30% after 2 min PW-HIFU exposure and increased to~70% after 32 min. Furthermore, addition of microbubbles to the liposomes prior to PW-HIFU exposure did not result in more release, which suggests that cavitation can be excluded as the main mechanism responsible for the

  17. An MR-compliant phased-array HIFU transducer with augmented steering range, dedicated to abdominal thermotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Auboiroux, Vincent [Inserm, U556, Lyon, F-69003 (France); Dumont, Erik [Image Guided Therapy, Pessac, Bordeaux (France); Petrusca, Lorena; Salomir, Rares [Faculty of Medicine, University of Geneva (Switzerland); Viallon, Magalie, E-mail: vincent.auboiroux@unige.ch [Radiology Department, University Hospital of Geneva, Geneva (Switzerland)

    2011-06-21

    A novel architecture for a phased-array high intensity focused ultrasound (HIFU) device was investigated, aiming to increase the capabilities of electronic steering without reducing the size of the elementary emitters. The principal medical application expected to benefit from these developments is the time-effective sonication of large tumours in moving organs. The underlying principle consists of dividing the full array of transducers into multiple sub-arrays of different resonance frequencies, with the reorientation of these individual emitters, such that each sub-array can focus within a given spatial zone. To enable magnetic resonance (MR) compatibility of the device and the number of output channels from the RF generator to be halved, a passive spectral multiplexing technique was used, consisting of parallel wiring of frequency-shifted paired piezoceramic emitters with intrinsic narrow-band response. Two families of 64 emitters (circular, 5 mm diameter) were mounted, with optimum efficiency at 0.96 and 1.03 MHz, respectively. Two different prototypes of the HIFU device were built and tested, each incorporating the same two families of emitters, but differing in the shape of the rapid prototyping plastic support that accommodated the transducers (spherical cap with radius of curvature/aperture of 130 mm/150 mm and, respectively, 80 mm/110 mm). Acoustic measurements, MR-acoustic radiation force imaging (ex vivo) and MR-thermometry (ex vivo and in vivo) were used for the characterization of the prototypes. Experimental results demonstrated an augmentation of the steering range by 80% along one preferentially chosen axis, compared to a classic spherical array of the same total number of elements. The electric power density provided to the piezoceramic transducers exceeded 50 W cm{sup -2} CW, without circulation of coolant water. Another important advantage of the current approach is the versatility of reshaping the array at low cost.

  18. Mechanistic Effects of Calcitriol in Cancer Biology

    Directory of Open Access Journals (Sweden)

    Lorenza Díaz

    2015-06-01

    Full Text Available Besides its classical biological effects on calcium and phosphorus homeostasis, calcitriol, the active vitamin D metabolite, has a broad variety of actions including anticancer effects that are mediated either transcriptionally and/or via non-genomic pathways. In the context of cancer, calcitriol regulates the cell cycle, induces apoptosis, promotes cell differentiation and acts as anti-inflammatory factor within the tumor microenvironment. In this review, we address the different mechanisms of action involved in the antineoplastic effects of calcitriol.

  19. Boosting high-intensity focused ultrasound-induced anti-tumor immunity using a sparse-scan strategy that can more effectively promote dendritic cell maturation

    Directory of Open Access Journals (Sweden)

    Zhong Pei

    2010-01-01

    Full Text Available Abstract Background The conventional treatment protocol in high-intensity focused ultrasound (HIFU therapy utilizes a dense-scan strategy to produce closely packed thermal lesions aiming at eradicating as much tumor mass as possible. However, this strategy is not most effective in terms of inducing a systemic anti-tumor immunity so that it cannot provide efficient micro-metastatic control and long-term tumor resistance. We have previously provided evidence that HIFU may enhance systemic anti-tumor immunity by in situ activation of dendritic cells (DCs inside HIFU-treated tumor tissue. The present study was conducted to test the feasibility of a sparse-scan strategy to boost HIFU-induced anti-tumor immune response by more effectively promoting DC maturation. Methods An experimental HIFU system was set up to perform tumor ablation experiments in subcutaneous implanted MC-38 and B16 tumor with dense- or sparse-scan strategy to produce closely-packed or separated thermal lesions. DCs infiltration into HIFU-treated tumor tissues was detected by immunohistochemistry and flow cytometry. DCs maturation was evaluated by IL-12/IL-10 production and CD80/CD86 expression after co-culture with tumor cells treated with different HIFU. HIFU-induced anti-tumor immune response was evaluated by detecting growth-retarding effects on distant re-challenged tumor and tumor-specific IFN-γ-secreting cells in HIFU-treated mice. Results HIFU exposure raised temperature up to 80 degrees centigrade at beam focus within 4 s in experimental tumors and led to formation of a well-defined thermal lesion. The infiltrated DCs were recruited to the periphery of lesion, where the peak temperature was only 55 degrees centigrade during HIFU exposure. Tumor cells heated to 55 degrees centigrade in 4-s HIFU exposure were more effective to stimulate co-cultured DCs to mature. Sparse-scan HIFU, which can reserve 55 degrees-heated tumor cells surrounding the separated lesions, elicited an

  20. The Biological Effects of Bilirubin Photoisomers.

    Directory of Open Access Journals (Sweden)

    Jana Jasprova

    Full Text Available Although phototherapy was introduced as early as 1950's, the potential biological effects of bilirubin photoisomers (PI generated during phototherapy remain unclear. The aim of our study was to isolate bilirubin PI in their pure forms and to assess their biological effects in vitro. The three major bilirubin PI (ZE- and EZ-bilirubin and Z-lumirubin were prepared by photo-irradiation of unconjugated bilirubin. The individual photoproducts were chromatographically separated (TLC, HPLC, and their identities verified by mass spectrometry. The role of Z-lumirubin (the principle bilirubin PI on the dissociation of bilirubin from albumin was tested by several methods: peroxidase, fluorescence quenching, and circular dichroism. The biological effects of major bilirubin PI (cell viability, expression of selected genes, cell cycle progression were tested on the SH-SY5Y human neuroblastoma cell line. Lumirubin was found to have a binding site on human serum albumin, in the subdomain IB (or at a close distance to it; and thus, different from that of bilirubin. Its binding constant to albumin was much lower when compared with bilirubin, and lumirubin did not affect the level of unbound bilirubin (Bf. Compared to unconjugated bilirubin, bilirubin PI did not have any effect on either SH-SY5Y cell viability, the expression of genes involved in bilirubin metabolism or cell cycle progression, nor in modulation of the cell cycle phase. The principle bilirubin PI do not interfere with bilirubin albumin binding, and do not exert any toxic effect on human neuroblastoma cells.

  1. Method for photo-altering a biological system to improve biological effect

    Science.gov (United States)

    Hill, Richard A.; Doiron, Daniel R.; Crean, David H.

    2000-08-01

    Photodynamic therapy is a new adjunctive therapy for filtration surgery that does not use chemotherapy agents or radiation, but uses pharmacologically-active sensitizing compounds to produce a titratable, localized, transient, post operative avascular conjunctiva. A photosensitizing agent in a biological system is selectively activated by delivering the photosensitive agent to the biological system and laser activating only a spatially selected portion of the delivered photosensitive agent. The activated portion of the photosensitive agent reacts with the biological system to obtain a predetermined biological effect. As a result, an improved spatial disposition and effectuation of the biological effect by the photosensitive agent in the biological system is achieved.

  2. Isoflavones: estrogenic activity, biological effect and bioavailability.

    Science.gov (United States)

    Vitale, Daniela Cristina; Piazza, Cateno; Melilli, Barbara; Drago, Filippo; Salomone, Salvatore

    2013-03-01

    Isoflavones are phytoestrogens with potent estrogenic activity; genistein, daidzein and glycitein are the most active isoflavones found in soy beans. Phytoestrogens have similarity in structure with the human female hormone 17-β-estradiol, which can bind to both alpha and beta estrogen receptors, and mimic the action of estrogens on target organs, thereby exerting many health benefits when used in some hormone-dependent diseases. Numerous clinical studies claim benefits of genistein and daidzein in chemoprevention of breast and prostate cancer, cardiovascular disease and osteoporosis as well as in relieving postmenopausal symptoms. The ability of isoflavones to prevent cancer and other chronic diseases largely depends on pharmacokinetic properties of these compounds, in particular absorption and distribution to the target tissue. The chemical form in which isoflavones occur is important because it influences their bioavailability and, therefore, their biological activity. Glucose-conjugated isoflavones are highly polar, water-soluble compounds. They are hardly absorbed by the intestinal epithelium and have weaker biological activities than the corresponding aglycone. Different microbial families of colon can transform glycosylated isoflavones into aglycones. Clinical studies show important differences between the aglycone and conjugated forms of genistein and daidzein. The evaluation of isoflavone metabolism and bioavailability is crucial to understanding their biological effects. Lipid-based formulations such as drug incorporation into oils, emulsions and self-microemulsifying formulations have been introduced to increase bioavailability. Complexation with cyclodextrin also represent a valid method to improve the physicochemical characteristics of these substances in order to be absorbed and distributed to target tissues. We review and discuss pharmacokinetic issues that critically influence the biological activity of isoflavones.

  3. Relationship between the temperature and the acoustic nonlinearity parameter in biological tissues

    Institute of Scientific and Technical Information of China (English)

    LU Ying; LIU Xiaozhou; GONG Xiufen; ZHANG Dong

    2004-01-01

    Recently with the rapid development of the high-intensity focused ultrasound (HIFU) in biomedical ultrasound, much attention has been paid to the noninvasive temperature estimation in biological tissue in order to determine the region and degree of the ultrasound-induced lesions. In ultrasound hyperthermal therapy it is highly desirable to study the real-time noninvasive monitoring of temperature distribution in biological tissue. In this paper, the relationship between the nonlinearity parameter B/A and the temperature in biological tissue is studied and compared with the theoretical model as well as the experimental results from the thermocouple. Results indicated that B/A could be used as an effective tool to monitor the temperature distribution in biological media.

  4. Biological effects data: Fluoride and sulfur dioxide

    Energy Technology Data Exchange (ETDEWEB)

    McMechan, K.J. (ed.); Holton, R.L.; Ulbricht, R.J.; Morgan , J.B.

    1975-04-01

    The Alumax Pacific Aluminum Corporation has proposed construction of an aluminum reduction facility near Youngs Bay at Warrenton, Oregon. This report comprises one part of the final report to Alumax on a research project entitled, Physical, Chemical and Biological Studies of Youngs Bay.'' It presents data pertaining to the potential biological effects of fluoride and sulfur dioxide, two potentially hazardous plant-stack emissions, on selected aquatic species of the area. Companion volumes provide a description of the physical characteristics the geochemistry, and the aquatic animals present in Youngs Bay and adjacent ecosystems. An introductory volume provides general information and maps of the area, and summarizes the conclusions of all four studies. The data from the two phases of the experimental program are included in this report: lethal studies on the effects of selected levels of fluoride and sulfur dioxide on the survival rate of eleven Youngs Bay faunal species from four phyla, and sublethal studies on the effects of fluoride and sulfur dioxide on the rate of primary production of phytoplankton. 44 refs., 18 figs., 38 tabs.

  5. Xenon preconditioning: molecular mechanisms and biological effects

    Directory of Open Access Journals (Sweden)

    Liu Wenwu

    2013-01-01

    Full Text Available Abstract Xenon is one of noble gases and has been recognized as an anesthetic for more than 50 years. Xenon possesses many of the characteristics of an ideal anesthetic, but it is not widely applied in clinical practice mainly because of its high cost. In recent years, numerous studies have demonstrated that xenon as an anesthetic can exert neuroprotective and cardioprotective effects in different models. Moreover, xenon has been applied in the preconditioning, and the neuroprotective and cardioprotective effects of xenon preconditioning have been investigated in a lot of studies in which some mechanisms related to these protections are proposed. In this review, we summarized these mechanisms and the biological effects of xenon preconditioning.

  6. Echinococcus granulosus: protoscolicidal effect of high intensity focused ultrasound.

    Science.gov (United States)

    Zou, Xiaoyi; Wang, Junan; Zhao, Hailong; Zhang, Jing; Wu, Weihua; Ye, Bin

    2009-04-01

    High intensity focused ultrasound (HIFU) is a new non-invasive technique which can cause cell death and tissue necrosis by focusing high-energy ultrasonic waves on a single location. The aim of our work is to investigate the damaging effect of HIFU on Echinococcus granulosus protoscolices, as well as its inhibitory effect on growth of hydatid cysts derived from protoscolices. The damaging effect of HIFU on protoscolices was investigated by following parasite mortality after irradiation, while the inhibitory effect was investigated by infection experiments in vivo. The results demonstrated that HIFU was able to damage protoscolices and the protoscolicidal effect was dose-dependent and showed late-onset. The growth of protoscolices that survived the exposure to HIFU was obviously suppressed in vitro, and the mean weight of hydatid cysts resulting from such protoscolices in the experimental group was less than that in controls. Evidences including the protoscolicidal effect, fragmentized protoscolices and low post exposure temperatures, suggest that cavitation may contribute to the protoscolicidal effect of HIFU. In addition, the structure of the germinal membrane in cysts developing from the irradiated protoscolices was not as normal or intact as that from non-irradiated ones, and morphological changes related to degeneration were observed, suggesting that HIFU could prevent protoscolices from developing normal germinal membrane and consequently stop the proliferation of secondary hydatid cysts. HIFU demonstrated damaging effect on protoscolices, inhibited the growth of protoscolices in vitro and in vivo, and could be a possible therapeutic option for cystic echinococcosis.

  7. Cardiac Ventricular HIFU: Convergence of Experiment and Theory in the Canine Model

    Science.gov (United States)

    Muratore, Robert; Abe, Yukio; Homma, Shunichi; Bernardi, Richard; Kalisz, Andrew; Feleppa, Ernest J.

    2007-05-01

    OBJECTIVE: HIFU is a promising technique for treating cardiac ventricular diseases such as sustained ventricular tachycardia. Ablations can potentially destroy arrhythmogenic foci and block reentrant circuits. Towards this end, we have learned to control HIFU lesions in the canine model in vivo. METHODS: Experiment — Thoracotomies were performed on anesthetized dogs, following IACUC guidelines. In this open-chest configuration, a polyethylene water-filled bag was coupled to the myocardium with degassed ultrasound gel. The transducer was lowered into the water. Ventricular locations were targeted and insonified with multiple 200-ms HIFU bursts of 60-W acoustic power; the bursts were triggered with the electrocardiogram QRS complex. The therapeutic transducer was a 35-mm focal length, 33-mm diameter PZT annular array, excited at 5.25 MHz. Its -3dB focal region dimensions were 2.5 mm axially and 0.3 mm transversely. A confocal diagnostic transducer was used for aiming and for recording backscattered radiofrequency ultrasound data. Theory — A comprehensive acoustic model has been developed. Individual modules numerically simulate physical processes such as ultrasound beam propagation, energy transfer, and heat flow within tissue. One set of modules simulates HIFU ablation in moving tissue. Tissue motion was obtained from digitized B-mode videos of transverse cross sections of a beating canine heart. Epicardial and endocardial surface positions were extracted from the video frames. Additional simulations of static tissue compared linear and nonlinear propagation models. RESULTS: Significant agreement between simulated and measured lesion sizes and between linear and nonlinear propagation models was demonstrated.

  8. MRgHIFU: Feedback temperature control with automatic deduction of BHT tissue parameters

    Science.gov (United States)

    Mougenot, Charles; Kabongo, Luis; Quesson, Bruno; Moonen, Chrit T. W.

    2009-04-01

    The Bio Heat Transfer Equation (BHTE) has been shown to be an efficient tissue representation during HIFU heating. This model requires knowledge of the following tissue parameters: ultrasound absorption, thermal diffusion and perfusion. The proposed technique, comparing BHTE simulation with MR thermal map, provides in real time an accurate and stable measurement of the ultrasound absorption and thermal diffusion and can be used to measure also perfusion. Therefore, temperature feedback control is significantly improved with more stable and faster convergence of the temperature.

  9. A Split-and-Merge-Based Uterine Fibroid Ultrasound Image Segmentation Method in HIFU Therapy.

    Directory of Open Access Journals (Sweden)

    Menglong Xu

    Full Text Available High-intensity focused ultrasound (HIFU therapy has been used to treat uterine fibroids widely and successfully. Uterine fibroid segmentation plays an important role in positioning the target region for HIFU therapy. Presently, it is completed by physicians manually, reducing the efficiency of therapy. Thus, computer-aided segmentation of uterine fibroids benefits the improvement of therapy efficiency. Recently, most computer-aided ultrasound segmentation methods have been based on the framework of contour evolution, such as snakes and level sets. These methods can achieve good performance, although they need an initial contour that influences segmentation results. It is difficult to obtain the initial contour automatically; thus, the initial contour is always obtained manually in many segmentation methods. A split-and-merge-based uterine fibroid segmentation method, which needs no initial contour to ensure less manual intervention, is proposed in this paper. The method first splits the image into many small homogeneous regions called superpixels. A new feature representation method based on texture histogram is employed to characterize each superpixel. Next, the superpixels are merged according to their similarities, which are measured by integrating their Quadratic-Chi texture histogram distances with their space adjacency. Multi-way Ncut is used as the merging criterion, and an adaptive scheme is incorporated to decrease manual intervention further. The method is implemented using Matlab on a personal computer (PC platform with Intel Pentium Dual-Core CPU E5700. The method is validated on forty-two ultrasound images acquired from HIFU therapy. The average running time is 9.54 s. Statistical results showed that SI reaches a value as high as 87.58%, and normHD is 5.18% on average. It has been demonstrated that the proposed method is appropriate for segmentation of uterine fibroids in HIFU pre-treatment imaging and planning.

  10. Assessment of HIFU lesions by shear-wave elastography: Initial in-vivo results

    Science.gov (United States)

    Anquez, Jeremie; Corréas, Jean-Michel; Criton, Aline; Lacoste, François; Yon, Sylvain

    2012-11-01

    The aim of this work was to evaluate Shear Wave Elastography (SWE) as a tool to visualize HIFU lesions in an acute in-vivo setting. Extracorporeal HIFU sonications of liver were performed on 14 rabbits in 19 consecutive, adjacent pulses, with in situ energies between 75 J and 228 J. A set of images of the sonicated area was acquired prior and post HIFU ablation: 2 orthogonal SWE images (transverse and sagittal) and contrast enhanced CT scan. SWE images were acquired with theAixplorer® device (SuperSonic Imagine, Aix, France). Prior to the treatment, the liver elasticity appeared homogeneous, with a elasticity comprised between 5 and 11 kPa. The lesion extents were manually segmented on post-treatment SWE images and their areas A(SWE)T (transverse) and A(SWE)S (sagittal) were computed. On 3D CT the lesions were segmented as a hypo intense (devascularized) region on 3D CT images, and considered as "ground truth". The transverse and sagittal planes passing by their centers of mass were extracted. The lesion areas were computed for each plane, respectively A(CT)T and A(CT)S. The ratios A(CT)T/A(SWE)T and A(CT)S/A(SWE)S were computed for all the 14 cases. SWE appear to underestimate the lesion extent in the sagittal orientation with respect to CT images, while a good matching is obtained in the transverse orientation.

  11. Temperature-dependent Physical Properties of a HIFU Blood Mimicking Fluid

    Science.gov (United States)

    Liu, Yunbo; Maruvada, Subha; King, Randy L.; Herman, Bruce A.; Wear, Keith A.

    2009-04-01

    A blood mimicking fluid (BMF) has been developed and characterized in a temperature dependent manner for high intensity focused ultrasound (HIFU) ablation devices. The BMF is based on a degassed and de-ionized water solution dispersed with low density polyethylene micro-spheres, nylon particles, gellan gum and glycerol. A broad range of physical parameters, including frequency dependent ultrasound attenuation, speed of sound, viscosity, thermal conductivity and diffusivity were characterized as a function of temperature (20° C to 70° C). The nonlinear parameter B/A and backscatter coefficient were also measured at room temperature. The attenuation coefficient is linearly proportional to the frequency (2 MHz-8 MHz) with a slope of about 0.2 dB cm-1 MHz-1 in the 20° C to 70° C range as has been reported for human blood. All the other temperature dependent physical parameters are also close to the reported values in human blood. These properties make the BMF a useful HIFU research tool for developing standardized exposimetry techniques, validating numerical models, and determining the safety and efficacy of HIFU ablation devices.

  12. Multimodality treatment by FOLFOX plus HIFU in a case of advanced pancreatic carcinoma. A case report.

    Science.gov (United States)

    Dimitrov, Dobromir; Andreev, Tihomir; Feradova, Hyuliya; Ignatov, Borislav; Zhou, Kunn; Johnson, Colin; Delijski, Tashko; Gortchev, Grigor; Tomov, Slavcho

    2015-01-31

    Pancreatic cancer is one of the most aggressive malignant diseases in which the survival rate has not improved in the past 40 years. A fifty-one-year-old male patient with inoperable metastatic pancreatic cancer and low response to chemotherapy with gemcitabine as single therapy underwent palliative high intensity focused ultrasound (HIFU) ablation. Continuing chemotherapy with folinic acid, oxaliplatin and 5-fluorouracil (FOLFOX) was made. Tools, provided by the European Organization for Research and Treatment of Cancer (EORTC) were used to evaluate his quality of life. The Global Health Status improved from 25 to 42 out of 100 and the body mass index (BMI) increased from 14.9 to 18.1 kg/m(2). Measured by the visual analog scale, the pain was reduced from 7 to 2 out of 10. Twelve months after the HIFU ablation, CT revealed decreased size of the tumor and liver lesions. FOLFOX plus interventional, physical destruction of the primary tumor by HIFU sufficiently improved the quality of life, reduced pancreatic pain and provided better survival in this case.

  13. Multimodality Treatment by FOLFOX plus HIFU in a Case of Advanced Pancreatic Carcinoma. A Case Report

    Directory of Open Access Journals (Sweden)

    Dobromir Dimitrov

    2015-01-01

    Full Text Available Context Pancreatic cancer is one of the most aggressive malignant diseases in which the survival rate has not improved in the past 40 years. Case report A fifty-one-year-old male patient with inoperable metastatic pancreatic cancer and low response to chemotherapy with gemcitabine as single therapy underwent palliative high intensity focused ultrasound (HIFU ablation. Continuing chemotherapy with folinic acid, oxaliplatin and 5-fluorouracil (FOLFOX was made. Tools, provided by the European Organization for Research and Treatment of Cancer (EORTC were used to evaluate his quality of life. The Global Health Status improved from 25 to 42 out of 100 and the body mass index (BMI increased from 14.9 to 18.1 kg/m2. Measured by the visual analog scale, the pain was reduced from 7 to 2 out of 10. Twelve months after the HIFU ablation, CT revealed decreased size of the tumor and liver lesions. Conclusion FOLFOX plus interventional, physical destruction of the primary tumor by HIFU sufficiently improved the quality of life, reduced pancreatic pain and provided better survival in this case.

  14. Processing ultrasound backscatter to monitor high-intensity focused ultrasound (HIFU) therapy

    Science.gov (United States)

    Kaczkowski, Peter J.; Anand, Ajay; Bailey, Michael R.

    2005-09-01

    The development of new noninvasive surgical methods such as HIFU for the treatment of cancer and internal bleeding requires simultaneous development of new sensing approaches to guide, monitor, and assess the therapy. Ultrasound imaging using echo amplitude has long been used to map tissue morphology for diagnostic interpretation by the clinician. New quantitative ultrasonic methods that rely on amplitude and phase processing for tissue characterization are being developed for monitoring of ablative therapy. We have been developing the use of full wave ultrasound backscattering for real-time temperature estimation, and to image changes in tissue backscatter spectrum as therapy progresses. Both approaches rely on differential processing of the backscatter signal in time, and precise measurement of phase differences. Noise and artifacts from motion and nonstationary speckle statistics are addressed by constraining inversions for tissue parameters with physical models. We present results of HIFU experiments with static point and scanned HIFU exposures in which temperature rise can be accurately mapped using a new heat transfer equation (HTE) model-constrained inverse approach. We also present results of a recently developed spectral imaging method that elucidates microbubble-mediated nonlinearity not visible as a change in backscatter amplitude. [Work supported by Army MRMC.

  15. Biological effects of space radiation and development of effective countermeasures

    Science.gov (United States)

    Kennedy, Ann R.

    2014-04-01

    As part of a program to assess the adverse biological effects expected from astronauts' exposure to space radiation, numerous different biological effects relating to astronauts' health have been evaluated. There has been major focus recently on the assessment of risks related to exposure to solar particle event (SPE) radiation. The effects related to various types of space radiation exposure that have been evaluated are: gene expression changes (primarily associated with programmed cell death and extracellular matrix (ECM) remodeling), oxidative stress, gastrointestinal tract bacterial translocation and immune system activation, peripheral hematopoietic cell counts, emesis, blood coagulation, skin, behavior/fatigue (including social exploration, submaximal exercise treadmill and spontaneous locomotor activity), heart functions, alterations in biological endpoints related to astronauts' vision problems (lumbar puncture/intracranial pressure, ocular ultrasound and histopathology studies), and survival, as well as long-term effects such as cancer and cataract development. A number of different countermeasures have been identified that can potentially mitigate or prevent the adverse biological effects resulting from exposure to space radiation.

  16. The biologically effective dose in inhalation nanotoxicology.

    Science.gov (United States)

    Donaldson, Ken; Schinwald, Anja; Murphy, Fiona; Cho, Wan-Seob; Duffin, Rodger; Tran, Lang; Poland, Craig

    2013-03-19

    In all branches of toxicology, the biologically effective dose (BED) is the fraction of the total dose of a toxin that actually drives any toxic effect. Knowledge of the BED has a number of applications including in building structure-activity relationships, the selection of metrics, the design of safe particles, and the determination of when a nanoparticle (NP) can be considered to be "new" for regulatory purposes. In particle toxicology, we define the BED as "the entity within any dose of particles in tissue that drives a critical pathophysiogically relevant form of toxicity (e.g., oxidative stress, inflammation, genotoxicity, or proliferation) or a process that leads to it." In conventional chemical toxicology, researchers generally use the mass as the metric to describe dose (such as mass per unit tissue or cells in culture) because of its convenience. Concentration, calculated from mass, may also figure in any description of dose. In the case of a nanoparticle dose, researchers use either the mass or the surface area. The mass of nanoparticles is not the only driver of their activity: the surfaces of insoluble particles interact with biological systems, and soluble nanoparticles can release factors that interact with these systems. Nanoparticle shape can modify activity. In this Account, we describe the current knowledge of the BED as it pertains to different NP types. Soluble toxins released by NPs represent one potential indicator of BED for wholly or partially soluble NPs composed of copper or zinc. Rapid dissolution of these NPs into their toxic ions in the acidic environment of the macrophage phagolysosome causes those ions to accumulate, which leads to lysosome destabilization and inflammation. In contrast, soluble NPs that release low toxicity ions, such as magnesium oxide NPs, are not inflammogenic. For insoluble NPs, ζ potential can serve as a BED measurement because the exposure of the particle surface to the acidic milieu of the phagolysosome and

  17. Cell Biology of Thiazide Bone Effects

    Science.gov (United States)

    Gamba, Gerardo; Riccardi, Daniela

    2008-09-01

    The thiazide-sensitive Na+:Cl- cotransporter (NCC) is the major pathway for salt reabsorption in the mammalian kidney. The activity of NCC is not only related to salt metabolism, but also to calcium and magnesium homeostasis due to the inverse relationship between NCC activity and calcium reabsorption. Hence, the thiazide-type diuretics that specifically block NCC have been used for years, not only for treatment of hypertension and edematous disease, but also for the management of renal stone disease. Epidemiological studies have shown that chronic thiazide treatment is associated with higher bone mineral density and reduced risk of bone fractures, which can only partly be explained in terms of their effects on the kidney. In this regard, we have recently shown that NCC is expressed in bone cells and that inhibition of NCC in bone, either by thiazides or by reduction of NCC protein with specific siRNA, is associated with increased mineralization in vitro. These observations open a field of study to begin to understand the cell biology of the beneficial effects of thiazides in bone.

  18. What Makes Biology Learning Difficult and Effective: Students' Views

    Science.gov (United States)

    Cimer, Atilla

    2012-01-01

    The present study aims to determine the biological topics that students have difficulties learning, the reasons why secondary school students have difficulties in learning biology, and ways to improve the effectiveness of students' biology learning. For these purposes, a self-administered questionnaire including three open-ended questions was…

  19. Increasing the HIFU ablation rate through an MRI-guided sonication strategy using shock waves : feasibility in the in vivo porcine liver

    NARCIS (Netherlands)

    Ramaekers, P; de Greef, M; van Breugel, J M M; Moonen, C T W; Ries, M

    2016-01-01

    This study investigated whether an MR-guided pulsed HIFU ablation strategy could be implemented under clinical conditions, using a transducer designed for uterine fibroid ablation, to obtain an ablation rate that is sufficiently high for clinical abdominal HIFU therapy in highly perfused organs. A p

  20. Biologically based multistage modeling of radiation effects

    Energy Technology Data Exchange (ETDEWEB)

    William Hazelton; Suresh Moolgavkar; E. Georg Luebeck

    2005-08-30

    This past year we have made substantial progress in modeling the contribution of homeostatic regulation to low-dose radiation effects and carcinogenesis. We have worked to refine and apply our multistage carcinogenesis models to explicitly incorporate cell cycle states, simple and complex damage, checkpoint delay, slow and fast repair, differentiation, and apoptosis to study the effects of low-dose ionizing radiation in mouse intestinal crypts, as well as in other tissues. We have one paper accepted for publication in ''Advances in Space Research'', and another manuscript in preparation describing this work. I also wrote a chapter describing our combined cell-cycle and multistage carcinogenesis model that will be published in a book on stochastic carcinogenesis models edited by Wei-Yuan Tan. In addition, we organized and held a workshop on ''Biologically Based Modeling of Human Health Effects of Low dose Ionizing Radiation'', July 28-29, 2005 at Fred Hutchinson Cancer Research Center in Seattle, Washington. We had over 20 participants, including Mary Helen Barcellos-Hoff as keynote speaker, talks by most of the low-dose modelers in the DOE low-dose program, experimentalists including Les Redpath (and Mary Helen), Noelle Metting from DOE, and Tony Brooks. It appears that homeostatic regulation may be central to understanding low-dose radiation phenomena. The primary effects of ionizing radiation (IR) are cell killing, delayed cell cycling, and induction of mutations. However, homeostatic regulation causes cells that are killed or damaged by IR to eventually be replaced. Cells with an initiating mutation may have a replacement advantage, leading to clonal expansion of these initiated cells. Thus we have focused particularly on modeling effects that disturb homeostatic regulation as early steps in the carcinogenic process. There are two primary considerations that support our focus on homeostatic regulation. First, a number of

  1. Biological Effects on the Source of Geoneutrinos

    Science.gov (United States)

    Sleep, Norman H.; Bird, Dennis K.; Rosing, Minik T.

    2013-11-01

    Detection of antineutrinos from U and Th series decay within the Earth (geoneutrinos) constrains the absolute abundance of these elements. Marine detectors will measure the ratio over the mantle beneath the site and provide spatial averaging. The measured mantle Th/U may well be significantly below its bulk earth value of 4; Pb isotope measurements on mantle-derived rocks yield low Th/U values, effectively averaged over geological time. The physics of the modern biological process is complicated, but the net effect is that much of the U in the mantle comes from subducted marine sediments and subducted upper oceanic crust. That is, U subducts preferentially relative to Th. Oxygen ultimately from photosynthesis oxidizes U(IV) to U(VI), which is soluble during weathering and sediment transport. Dissolved U(VI) reacts with FeO in the oceanic crust and organic carbon within sediments to become immobile U(IV). These deep marine rocks are preferentially subducted relative to Th(IV)-bearing continental margin rocks. Ferric iron from anoxygenic photosynthesis and oxygen in local oases likely mobilized some U during the Archean Era when there was very little O2 in the air. Conversely, these elements behave similarly in the absence of life, where the elements occur as U(IV) and Th(IV), which do not significantly fractionate during igneous processes. Neither do they fractionate during weathering, as they are essentially insoluble in water in surface environments. Th(IV) and U(IV) remain in solid clay-sized material. Overall, geoneutrino data constrain the masses of mantle chemical and isotopic domains recognized by studies of mantle-derived rocks and show the extent of recycling into the mantle over geological time.

  2. Radiation-force-based estimation of acoustic attenuation using harmonic motion imaging (HMI) in phantoms and in vitro livers before and after HIFU ablation.

    Science.gov (United States)

    Chen, Jiangang; Hou, Gary Y; Marquet, Fabrice; Han, Yang; Camarena, Francisco; Konofagou, Elisa

    2015-10-07

    Acoustic attenuation represents the energy loss of the propagating wave through biological tissues and plays a significant role in both therapeutic and diagnostic ultrasound applications. Estimation of acoustic attenuation remains challenging but critical for tissue characterization. In this study, an attenuation estimation approach was developed using the radiation-force-based method of harmonic motion imaging (HMI). 2D tissue displacement maps were acquired by moving the transducer in a raster-scan format. A linear regression model was applied on the logarithm of the HMI displacements at different depths in order to estimate the acoustic attenuation. Commercially available phantoms with known attenuations (n = 5) and in vitro canine livers (n = 3) were tested, as well as HIFU lesions in in vitro canine livers (n = 5). Results demonstrated that attenuations obtained from the phantoms showed a good correlation (R² = 0.976) with the independently obtained values reported by the manufacturer with an estimation error (compared to the values independently measured) varying within the range of 15-35%. The estimated attenuation in the in vitro canine livers was equal to 0.32   ±   0.03 dB cm(-1) MHz(-1), which is in good agreement with the existing literature. The attenuation in HIFU lesions was found to be higher (0.58   ±   0.06 dB cm(-1) MHz(-1)) than that in normal tissues, also in agreement with the results from previous publications. Future potential applications of the proposed method include estimation of attenuation in pathological tissues before and after thermal ablation.

  3. Effects of biological sex on the pathophysiology of the heart

    National Research Council Canada - National Science Library

    Fazal, Loubina; Azibani, Feriel; Vodovar, Nicolas; Cohen Solal, Alain; Delcayre, Claude; Samuel, Jane‐Lise

    2014-01-01

    .... While the effects of biological sex on cardiovascular pathophysiology have long been known, the sex-specific mechanisms mediating these processes have been further elucidated over recent years...

  4. High intensity focused ultrasound (HIFU) applied to hepato-bilio-pancreatic and the digestive system—current state of the art and future perspectives

    Science.gov (United States)

    Diana, Michele; Schiraldi, Luigi; Liu, Yu-Yin; Memeo, Riccardo; Mutter, Didier; Pessaux, Patrick

    2016-01-01

    Background High intensity focused ultrasound (HIFU) is emerging as a valid minimally-invasive image-guided treatment of malignancies. We aimed to review to current state of the art of HIFU therapy applied to the digestive system and discuss some promising avenues of the technology. Methods Pertinent studies were identified through PubMed and Embase search engines using the following keywords, combined in different ways: HIFU, esophagus, stomach, liver, pancreas, gallbladder, colon, rectum, and cancer. Experimental proof of the concept of endoluminal HIFU mucosa/submucosa ablation using a custom-made transducer has been obtained in vivo in the porcine model. Results Forty-four studies reported on the clinical use of HIFU to treat liver lesions, while 19 series were found on HIFU treatment of pancreatic cancers and four studies included patients suffering from both liver and pancreatic cancers, reporting on a total of 1,682 and 823 cases for liver and pancreas, respectively. Only very limited comparative prospective studies have been reported. Conclusions Digestive system clinical applications of HIFU are limited to pancreatic and liver cancer. It is safe and well tolerated. The exact place in the hepatocellular carcinoma (HCC) management algorithm remains to be defined. HIFU seems to add clear survival advantages over trans arterial chemo embolization (TACE) alone and similar results when compared to radio frequency (RF). For pancreatic cancer, HIFU achieves consistent cancer-related pain relief. Further research is warranted to improve targeting accuracy and efficacy monitoring. Furthermore, additional work is required to transfer this technology on appealing treatments such as endoscopic HIFU-based therapies. PMID:27500145

  5. In Vitro Validation of a Sector-Switching HIFU Device for Accelerated Treatment

    Science.gov (United States)

    Petrusca, Lorena; Brasset, Lucie; Cotton, Francois; Salomir, Rares; Chapelon, Jean-Yves

    2009-04-01

    A sector-switching method that increases the HIFU sequence duty-cycle and reduces the equivalent treatment time was tested in vitro. The MR-compatible HIFU device used consisted of 2 symmetric sectors arranged on a truncated spherical cap (focus = 45 mm, long diameter = 57.5 mm, short diameter = 35 mm). A MR-compatible, 2D positioning system provided 0.5 mm accuracy. Two sonication sequences were considered, each with the same pattern for the focal point trajectory and with identical on-state power. First, both sectors radiated simultaneously, with a power duty cycle of 60%. Second, the sectors radiated separately with balanced temporally-interleaved sonication and a power duty cycle of 87.5%. Numerical simulations were performed to predict the shape of the lesion for a given set of sequence parameters, according to a theoretical model. Fast MR thermometry (voxel size: 0.85×0.85×4.25 mm3; temporal resolution: 2 sec) was performed in two orthogonal planes (sagittal and transverse) while the 2D sonication pattern was contained in the coronal plane. Fresh samples of degassed porcine liver were used, and the macroscopic lesions were measured after HIFU. The 14400 s equivalent thermal dose isolevel was compared respectively for the two sonication sequences, both with numerical simulations and experimental MR data. No susceptibility or RF artifacts could be detected on MR data. The lesion's size ratio between reference versus the sector-switched sequence was 1.12 from simulations and 1.25 (±3.2%) from MRI derived TD. Switching the device sectors reduced the treatment time by 20% while the shape and size of the lesions were maintained. In vivo studies are required for pre-clinical validation.

  6. SIX2 Effects on Wilms Tumor Biology

    Directory of Open Access Journals (Sweden)

    Janene Pierce

    2014-12-01

    Full Text Available Wilms tumor (WT blastema retains gene expression profiles characteristic of the multipotent nephron progenitor pool, or cap mesenchyme (CM, in the developing kidney. As a result, WT blastema and the CM are believed to represent contextual analogues of one another. Sine oculis homeobox 2 (SIX2 is a transcription factor expressed specifically in the CM, provides a critical mechanism for CM self-renewal, and remains persistently active in WT blastema, although its purpose in this childhood malignancy remains unclear. We hypothesized that SIX2, analogous to its function in development, confers a survival pathway to blastema, the putative WT stem cell. To test its functional significance in WT biology, wild-type SIX2 was overexpressed in the human WT cell line, WiT49. After validating this model, SIX2 effects on anchorage-independent growth, proliferation, invasiveness, canonical WNT pathway signaling, and gene expression of specific WNT pathway participants were evaluated. Relative to controls, WiT49 cells overexpressing SIX2 showed significantly enhanced anchorage-independent growth and early-passage proliferation representing surrogates of cell survival. Interestingly, overexpression of SIX2 generally repressed TCF/LEF-dependent canonical WNT signaling, which activates and coordinates both differentiation and stem pathways, but significantly heightened canonical WNT signaling through the survivin promoter, a mechanism that exclusively maintains the stem state. In summary, when overexpressed in a human WT cell line, SIX2 enhances cell survival and appears to shift the balance in WNT/β-catenin signaling away from a differentiation path and toward a stem cell survival path.

  7. T2-based temperature monitoring in abdominal fat during HIFU treatment of patients with uterine fibroids

    Science.gov (United States)

    Ozhinsky, Eugene; Kohi, Maureen; Ghanouni, Pejman; Rieke, Viola

    2017-03-01

    In this study, we have implemented T2-based monitoring of near-field heating in patients undergoing HIFU ablation of uterine fibroids using Insightec ExAblate system. In certain areas, near-field heating can reach 18°C and the tissue may experience sustained heating of more than 10°C for the period of 2 hours or more. This indicates a cumulative thermal dose that may cause necrosis. Our results show the feasibility and importance of measuring near-field heating in subcutaneous fat.

  8. Effects of Individualized Assignments on Biology Achievement.

    Science.gov (United States)

    Kremer, Philip L.

    1983-01-01

    Compared detailed (favoring field dependence and induction) and nondetailed (favoring field dependence and deduction) assignments on biology achievement of grade 10 male students (N=95) over a seven-month period. Detailed assignments, employing pictorial and verbal block diagrams and high structure, significantly enhanced learning among some…

  9. The Biological Effects of Nonionizing Radiation.

    Science.gov (United States)

    1981-12-29

    surrounding C-12-81 normal tissues. According to N.W. Bleehan, this was the method used by Hippocrates , with the aid of a hot iron. Hippocrates , by the way, is...temporal pattern of desired increases of tempera - ture in the body; (2) the biological consequences of doing this must be established and evaluated

  10. Technology Rich Biology Labs: Effects of Misconceptions.

    Science.gov (United States)

    Kuech, Robert; Zogg, Gregory; Zeeman, Stephan; Johnson, Mark

    This paper describes a study conducted on the lab sections of the general biology course for non-science majors at the University of New England, and reports findings of student misconceptions about photosynthesis and the mass/carbon uptake during plant growth. The current study placed high technology analytic tools in the hands of introductory…

  11. Non-invasive estimation of temperature using diagnostic ultrasound during HIFU therapy

    Science.gov (United States)

    Georg, O.; Wilkens, V.

    2017-03-01

    The use of HIFU for thermal ablation of human tissues requires safe real-time monitoring of the lesion formation during the treatment to avoid damage of the surrounding healthy tissues and to control temperature rise. Besides MR imaging, several methods have been proposed for temperature imaging using diagnostic ultrasound, and echoshift estimation (using speckle tracking) is the most promising and commonly used technique. It is based on the thermal dependence of the ultrasound echo that accounts for two different physical phenomena: local change in speed of sound and thermal expansion of the propagating medium due to changes in temperature. In our experiments we have used two separate transducers: HIFU exposure was performed using a 1.06 MHz single element focusing transducer of 64 mm aperture and 63.2 mm focal length; the ultrasound diagnostic probe of 11 MHz operated in B-mode for image guidance. The temperature measurements were performed in an agar-based tissue-mimicking phantom. To verify the obtained results, numerical modeling of the acoustic and temperature fields was carried out using KZK and Pennes Bioheat equations, as well as measurements with thermocouples were performed.

  12. A History of the Sonocare CST-100: The First FDA-approved HIFU Device

    Science.gov (United States)

    Muratore, Robert

    2006-05-01

    The Sonocare CST-100 Therapeutic Ultrasound System, designed for the treatment of glaucoma, was developed in the 1980s and became the first high intensity focused ultrasound (HIFU) device to receive Food and Drug Administration approval. The system arose from studies done by F.L. Lizzi, Eng.Sc.D., of Riverside Research Institute and D.J. Coleman, M.D., of Cornell Medical Center/New York Hospital on the safety of ultrasound diagnosis of the eye. As safety limits were probed, therapeutic regimes were discovered. Optimization of operational parameters, clinical experience, and engineering design came together through a spin-off company, Sonocare, Inc., formed to produce and market the ophthalmic device. Various precedents were set during the approval process, including the acceptance by the FDA of radiation momentum imparted to an absorber as a measure of acoustic power. Many devices were sold, but the laser industry, grandfathered into the therapeutic field, eventually out-marketed Sonocare. The CST-100 remains as a model of elegant industrial design, and existing units are used daily in HIFU laboratory experiments.

  13. Respiratory-Gated MRgHIFU in Upper Abdomen Using an MR-Compatible In-Bore Digital Camera

    Directory of Open Access Journals (Sweden)

    Vincent Auboiroux

    2014-01-01

    Full Text Available Objective. To demonstrate the technical feasibility and the potential interest of using a digital optical camera inside the MR magnet bore for monitoring the breathing cycle and subsequently gating the PRFS MR thermometry, MR-ARFI measurement, and MRgHIFU sonication in the upper abdomen. Materials and Methods. A digital camera was reengineered to remove its magnetic parts and was further equipped with a 7 m long USB cable. The system was electromagnetically shielded and operated inside the bore of a closed 3T clinical scanner. Suitable triggers were generated based on real-time motion analysis of the images produced by the camera (resolution 640×480 pixels, 30 fps. Respiratory-gated MR-ARFI prepared MRgHIFU ablation was performed in the kidney and liver of two sheep in vivo, under general anaesthesia and ventilator-driven forced breathing. Results. The optical device demonstrated very good MR compatibility. The current setup permitted the acquisition of motion artefact-free and high resolution MR 2D ARFI and multiplanar interleaved PRFS thermometry (average SNR 30 in liver and 56 in kidney. Microscopic histology indicated precise focal lesions with sharply delineated margins following the respiratory-gated HIFU sonications. Conclusion. The proof-of-concept for respiratory motion management in MRgHIFU using an in-bore digital camera has been validated in vivo.

  14. A framework for the correction of slow physiological drifts during MR-guided HIFU therapies : Proof of concept

    NARCIS (Netherlands)

    Zachiu, Cornel; de Senneville, Baudouin Denis; Moonen, Chrit; Ries, Mario

    2015-01-01

    Purpose: While respiratory motion compensation for magnetic resonance (MR)-guided high intensity focused ultrasound (HIFU) interventions has been extensively studied, the influence of slow physiological motion due to, for example, peristaltic activity, has so far been largely neglected. During lengt

  15. Non-Thermal Effects Mobile Phones at Biological Objects

    OpenAIRE

    Ladislav Balogh

    2003-01-01

    The article deals with non-thermal effects of mobile phones on biological objects. Even though these effects are observed for longer period, there are not so far unequivocal results on obtained biological and biophysical results in this field. Biologicaleffects of electromagnetic field (EMF) depend on its character, its duration as well as on features of organism. As the receptors offield are not known (e.g. inputs of EMF into organism), its effects are judged only by non-specific reaction of...

  16. An improved balloon snake for HIFU image-guided system.

    Science.gov (United States)

    Li, Zhong-Bing; Xu, Xian-Ze; Le, Yi; Xu, Feng-Qiu

    2014-07-01

    Target segmentation in ultrasound images is a key step in the definition of the intro-operative planning of high-intensity focused ultrasound therapy. This paper presents an improvement for the balloon snake in segmentation. A sign function, designed by the edge map and the moving snake, is added to give the direction of the balloon force on the moving snake separately. Segmentation results are demonstrated on ultrasound images and the effectiveness and convenience shown in applications.

  17. Topical Day on Biological Effects of Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Baatout, S.; Jacquet, P.

    1997-05-15

    The topical day has been focussed on the potential effects of ionizing radiation on human health. A general overview on molecular and biophysical aspects of radiation, its effects on cells and organisms, and the contribution of radiobiology to radiation protection and risk assessment is given. The genetic effects of radiation and its effects on the developing organism, the effects of radiation on the cell cycle and the mechanisms of radiation induced apoptosis were also discussed.

  18. Critical appraisal: dental amalgam update--part II: biological effects.

    Science.gov (United States)

    Wahl, Michael J; Swift, Edward J

    2013-12-01

    Dental amalgam restorations have been controversial for over 150 years. In Part I of this Critical Appraisal, the clinical efficacy of dental amalgam was updated. Here in Part II, the biological effects of dental amalgam are addressed.

  19. Iron diminishes the in vitro biological effect of vanadium.

    Science.gov (United States)

    Mechanistic pathways underlying inflammatory injury following exposures to vanadium-containing compounds are not defined. We tested the postulate that the in vitro biological effect of vanadium results from its impact on iron homeostasis. Human bronchial epithelial (HBE) cells ex...

  20. Effect of grain splitting on biology and development of ...

    African Journals Online (AJOL)

    Effect of grain splitting on biology and development of Callosobruchus Maculatus ... Data on oviposition, adult eclosion and weights of emergent adults were ... for C. maculatus at F1, F2 and F3 generations on spilt compared to whole grains.

  1. Some Biological Effects Of Ditching Tidewater Marshes Research Report 19

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Studies conducted over a 12-year period, 1935-47, of the biological effects of ditching tidewater marshes in Delaware for mosquito control showed that marked...

  2. Spatiotemporal filtering of MR-temperature artifacts arising from bowel motion during transurethral MR-HIFU

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, Alain, E-mail: aschmitt@sri.utoronto.ca [Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada); Mougenot, Charles [Philips Healthcare, 281 Hillmount Road, Markham, Ontario L6C 2S3 (Canada); Chopra, Rajiv [Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canadaand Department of Radiology, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9061 (United States)

    2014-11-01

    Purpose: Transurethral MR-HIFU is a minimally invasive image-guided treatment for localized prostate cancer that enables precise targeting of tissue within the gland. The treatment is performed within a clinical MRI to obtain real-time MR thermometry used as an active feedback to control the spatial heating pattern in the prostate and to monitor for potential damage to surrounding tissues. This requires that the MR thermometry measurements are an accurate representation of the true tissue temperature. The proton resonance frequency shift thermometry method used is sensitive to tissue motion and changes in the local magnetic susceptibility that can be caused by the motion of air bubbles in the rectum, which can impact the performance of transurethral MR-HIFU in these regions of the gland. Methods: A method is proposed for filtering of temperature artifacts based on the temporal variance of the temperature, using empirical and dynamic positional knowledge of the ultrasonic heating beam, and an estimation of the measurement noise. A two-step correction strategy is introduced which eliminates artifact-detected temperature variations while keeping the noise level low through spatial averaging. Results: The filter has been evaluated by postprocessing data from five human transurethral ultrasound treatments. The two-step correction process led to reduced final temperature standard deviation in the prostate and rectum areas where the artifact was located, without negatively affecting areas distal to the artifact. The performance of the filter was also found to be consistent across all six of the data sets evaluated. The evaluation of the detection criterion parameter M determined that a value of M = 3 achieves a conservative filter with minimal loss of spatial resolution during the process. Conclusions: The filter was able to remove most artifacts due to the presence of moving air bubbles in the rectum during transurethral MR-HIFU. A quantitative estimation of the filter

  3. Combination treatment of HIFU and rehabilitation on phantom limb pain after amputation%聚焦超声联合常规康复治疗对截肢后幻肢痛的疗效

    Institute of Scientific and Technical Information of China (English)

    唐映; 刘杰文; 许晓光

    2015-01-01

    目的:探讨聚焦超声联合常规康复对幻肢痛的治疗效果。方法将32例存在幻肢痛的患者分为治疗组和对照组,各16例,治疗组采用聚焦超声联合常规康复治疗,对照组单纯采用常规康复方法治疗。治疗30天后,以简明McGill疼痛问卷表评分作为评价指标,观察两组治疗效果。结果治疗组总有效率93.8%,对照组总有效率56.3%,两组比较差异有显著性意义(P<0.05);两组治疗前与治疗后SF-MPQ评分比较,差异均有显著性意义(P<0.05);治疗后组间SF-MPQ评分比较,差异有显著性意义(P<0.05)。结论聚焦超声和常规康复治疗联合运用对幻肢痛有很好的疗效。%Objective To study the effect of high intensity focus ultrasound ( HIFU) and rehabilitation treatment on phan-tom limb pain.Methods With randomized and controlled clinical research method, 32 cases of phantom limb pain were randomly divided into study group ( HIFU and rehabilitation therapy) and control group ( Rehabilitation therapy) with 16 patients in each group.After 30 days of treatment, a concise questionnaire SF-MPQ score was used as the evaluation in-dex of the therapeutic effect.Results The total effective rate of treatment group was 93.8%, compared to 56.3 % in the control group (P<0.05).The SF-MPQ score were significantly different before and after the treatment in both study group and control group (P<0.05).Comparison of SF-MPQ score between the two groups after treatment indicated sig-nificant difference (P<0.05).Conclusion HIFU and rehabilitation treatment have a good efficacy on limb pain.The combination of HIFU and rehabilitation treatment presents better results.

  4. Distinguishing between "function" and "effect" in genome biology.

    Science.gov (United States)

    Doolittle, W Ford; Brunet, Tyler D P; Linquist, Stefan; Gregory, T Ryan

    2014-05-09

    Much confusion in genome biology results from conflation of possible meanings of the word "function." We suggest that, in this connection, attention should be paid to evolutionary biologists and philosophers who have previously dealt with this problem. We need only decide that although all genomic structures have effects, only some of them should be said to have functions. Although it will very often be difficult or impossible to establish function (strictly defined), it should not automatically be assumed. We enjoin genomicists in particular to pay greater attention to parsing biological effects. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  5. Biological effects of exposure to magnetic resonance imaging: an overview

    OpenAIRE

    Formica Domenico; Silvestri Sergio

    2004-01-01

    Abstract The literature on biological effects of magnetic and electromagnetic fields commonly utilized in magnetic resonance imaging systems is surveyed here. After an introduction on the basic principles of magnetic resonance imaging and the electric and magnetic properties of biological tissues, the basic phenomena to understand the bio-effects are described in classical terms. Values of field strengths and frequencies commonly utilized in these diagnostic systems are reported in order to a...

  6. Hormesis [Biological Effects of Low Level Exposures (Belle)] and Dermatology

    OpenAIRE

    Thong, Haw-Yueh; Maibach, Howard I.

    2008-01-01

    Hormesis, or biological effects of low level exposures (BELLE), is characterized by nonmonotonic dose response which is biphasic, displaying opposite effects at low and high dose. Its occurrence has been documented across a broad range of biological models and diverse type of exposure. Since hormesis appears to be a relatively common phenomenon in many areas, the objective of this review is to explore its occurrence related to dermatology and its public health and risk assessment implication....

  7. Biological Effects of the Great Oxidation Event

    Science.gov (United States)

    Schopf, J.

    2012-12-01

    Fossil evidence of photoautotrophy, documented in Precambrian sediments by stromatolites, stromatolitic microfossils, and carbon isotopic data consistent with autotrophic CO2-fixation, extends to ~3,500 Ma. Such data, however, are insufficient to establish the time of origin of O2-producing (cyanobacterial) photosynthesis from its anoxygenic, photosynthetic bacterial, evolutionary precursor. The oldest (Paleoarchean) stromatolites may have been formed by anoxygenic photoautotrophs, rather than the cyanobacteria that dominate Proterozoic and modern stromatolites. Unlike the cyanobacteria of Proterozoic microbial assemblages, the filamentous and coccoidal microfossils of Archean deposits may represent remnants of non-O2-producing prokaryotes. And although the chemistry of Archean organic matter shows it to be biogenic, its carbon isotopic composition is insufficient to differentiate between oxygenic and anoxygenic sources. Though it is well established that Earth's ecosystem has been based on autotrophy since its early stages and that O2-producing photosynthesis evolved earlier, perhaps much earlier, than the increase of atmospheric oxygen in the ~2,450 and ~2,320 Ma Great Oxidation Event (GOE), the time of origin of oxygenic photoautotrophy has yet to be established. Recent findings suggest that Earth's ecosystem responded more or less immediately to the GOE. The increase of atmospheric oxygen markedly affected ocean water chemistry, most notably by increasing the availability of biologically usable oxygen (which enabled the development of obligate aerobes, such as eukaryotes), and of nitrate, sulfate and hydrogen sulfide (the increase of H2S being a result of microbial reduction of sulfate), the three reactants that power the anaerobic basis of sulfur-cycling microbial sulfuretums. Fossil evidence of the earliest eukaryotes (widely accepted to date from ~1800 Ma and, arguably, ~2200 Ma) fit this scenario, but the most telling example of life's response to the GOE

  8. A new FPGA-driven P-HIFU system with harmonic cancellation technique

    Science.gov (United States)

    Wu, Hao; Shen, Guofeng; Su, Zhiqiang; Chen, Yazhu

    2017-03-01

    This paper introduces a high intensity focused ultrasound system for ablation using switch-mode power amplifiers with harmonic cancellation technique eliminating the 3rdharmonic and all even harmonics. The efficiency of the amplifier is optimized by choosing different parameters of the harmonic cancellation technique. This technique requires double driving signals, and specific signal waveform because of the full-bridge topology. The new FPGA-driven P-HIFU system has 200 channels of phase signals that can form 100 output channels. An FPGA chip is used to generate these signals, and each channel has a phase resolution of 2 ns, less than one degree. The output waveform of the amplifier, voltage waveform across the transducer, shows fewer harmonic components.

  9. Interference-free ultrasound imaging during HIFU therapy, using software tools

    Science.gov (United States)

    Vaezy, Shahram (Inventor); Held, Robert (Inventor); Sikdar, Siddhartha (Inventor); Managuli, Ravi (Inventor); Zderic, Vesna (Inventor)

    2010-01-01

    Disclosed herein is a method for obtaining a composite interference-free ultrasound image when non-imaging ultrasound waves would otherwise interfere with ultrasound imaging. A conventional ultrasound imaging system is used to collect frames of ultrasound image data in the presence of non-imaging ultrasound waves, such as high-intensity focused ultrasound (HIFU). The frames are directed to a processor that analyzes the frames to identify portions of the frame that are interference-free. Interference-free portions of a plurality of different ultrasound image frames are combined to generate a single composite interference-free ultrasound image that is displayed to a user. In this approach, a frequency of the non-imaging ultrasound waves is offset relative to a frequency of the ultrasound imaging waves, such that the interference introduced by the non-imaging ultrasound waves appears in a different portion of the frames.

  10. Biological effects of fruit and vegetables

    DEFF Research Database (Denmark)

    Dragsted, L. O.; Krath, B.; Ravn-Haren, Gitte

    2006-01-01

    , enzyme inducers, apoptosis inducers etc. In human intervention studies the dose levels achieved tend to be lower than the levels found to be effective in animals and sampling from target organs is often not possible. A controlled dietary human intervention study was performed with forty-three volunteers...... and vegetables tends to increase the stability of lipids towards oxidative damage. Markers of oxidative enzymes indicate a steady increase in glutathione peroxidase (GPX1) activity in erythrocytes during intervention with fruit and vegetables but there is no effect on GPX1 transcription levels in leucocytes....... No change occurs in glutathione-conjugating or -reducing enzyme activities in erythrocytes or plasma, and there are no effects on the transcription of genes involved in phase 2 enzyme induction or DNA repair in leucocytes. Fruit and vegetable intake decreases the level of total cholesterol and LDL...

  11. Biological and therapeutical effects of Radon

    Energy Technology Data Exchange (ETDEWEB)

    Deetjen, P. [Institute of Physiologie and Balneologie, University of Innsbruck (Austria)

    1998-12-31

    In spas with a somewhat elevated Radon{sup 222} (Rn) activity (between 300 and 3000 Bq/l), the empirical medicine ended - in all parts of the world - with the same list of indications. It mainly includes the more painful rheumatic diseases such as deformation or degeneration of the joints and non bacterial inflammation of muscles, tendons or joints; Morbus Bechterew and other diseases of the vertebral column like spondylosis, spondylarthrosis or osteochondrosis. While informer times these effects were seldom documented in an objective manner, in recent years several prospective randomized double-blind studies proved the pain reducing efficacy of Radon therapy in patients with cervical pain syndromes, with chronic polyarthritis or with Morbus Bechterew. Studies in experimental animal models have accumulated remarkable data in organs, tissue and cultured cells that provide a rationale to explain the observed effects of Radon therapy in patients. (author)

  12. Palytoxin and Analogs: Biological and Ecological Effects

    Directory of Open Access Journals (Sweden)

    Vítor Ramos

    2010-06-01

    Full Text Available Palytoxin (PTX is a potent marine toxin that was originally found in soft corals from tropical areas of the Pacific Ocean. Soon after, its occurrence was observed in numerous other marine organisms from the same ecological region. More recently, several analogs of PTX were discovered, remarkably all from species of the dinoflagellate genus Ostreopsis. Since these dinoflagellates are also found in other tropical and even in temperate regions, the formerly unsuspected broad distribution of these toxins was revealed. Toxicological studies with these compounds shows repeatedly low LD50 values in different mammals, revealing an acute toxic effect on several organs, as demonstrated by different routes of exposure. Bioassays tested for some marine invertebrates and evidences from environmental populations exposed to the toxins also give indications of the high impact that these compounds may have on natural food webs. The recognition of its wide distribution coupled with the poisoning effects that these toxins can have on animals and especially on humans have concerned the scientific community. In this paper, we review the current knowledge on the effects of PTX and its analogs on different organisms, exposing the impact that these toxins may have in coastal ecosystems.

  13. Biological effects of stellar collapse neutrinos

    CERN Document Server

    Collar, J I

    1996-01-01

    Massive stars in their final stages of collapse radiate most of their binding energy in the form of MeV neutrinos. The recoil atoms that they produce in elastic scattering off nuclei in organic tissue create a radiation damage which is highly effective in the production of irreparable DNA harm, leading to cellular mutation, neoplasia and oncogenesis. Using a conventional model of the galaxy and of the collapse mechanism, the periodicity of nearby stellar collapses and the radiation dose are calculated. The possible contribution of this process to the paleontological record of mass extinctions is examined.

  14. Biological effects of fruit and vegetables

    DEFF Research Database (Denmark)

    Dragsted, L. O.; Krath, B.; Ravn-Haren, Gitte

    2006-01-01

    , providing 600hairspg fruit and vegetables/d or in the controls a carbohydrate-rich drink to balance energy intake. Surrogate markers of oxidative damage to DNA, protein and lipids, enzymic defence and lipid metabolism were determined in blood and urine. It was found that a high intake of fruit......, enzyme inducers, apoptosis inducers etc. In human intervention studies the dose levels achieved tend to be lower than the levels found to be effective in animals and sampling from target organs is often not possible. A controlled dietary human intervention study was performed with forty-three volunteers...

  15. Nanosilver – Harmful effects of biological activity

    Directory of Open Access Journals (Sweden)

    Anna Maria Świdwińska-Gajewska

    2014-12-01

    Full Text Available Nanosilver, also identified as colloidal silver, has been known and used for ages to combat diseases or prolong food freshness. It usually occurs in the form of a suspension consisting of particles of size < 100 nm. Due to its specific properties, silver nanoparticles are used in many technologies to produce medical devices, textiles, conductive materials or photovoltaic cells. The growing popularity of nanosilver applications increases the number of people occupationally exposed to this substance. Potential exposure routes for silver nanoparticles are through dermal, oral and inhalation pathways. Silver nanoparticles may be absorbed through the lungs, intestine, and through the skin into circulation and thus may reach such organs as the liver, kidney, spleen, brain, heart and testes. Nanosilver may cause mild eyes and skin irritations. It can also act as a mild skin allergen. Inhalation of silver nanoparticles mainly affects the lungs and liver. It has been demonstrated that silver nanoparticles may be genotoxic to mammalian cells. There are some alarming reports on the adverse effects of silver nanoparticles on reproduction of experimental animals. Exposure to silver nanoparticles may exert a neurotoxic effect and affect cognitive functions, causing the impairment of short-term and working memory. Maximum admissible concentration (MAC for the inhalable fraction of silver of 0.05 mg/m3 is currently binding in Poland. In light of toxicological studies of silver nanoparticles it seems reasonable to update the hygiene standards for silver with nanoparticles as a separate fraction. Med Pr 2014;65(6:831–845

  16. Biologic

    CERN Document Server

    Kauffman, L H

    2002-01-01

    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  17. Electromagnetic field induced biological effects in humans.

    Science.gov (United States)

    Kaszuba-Zwoińska, Jolanta; Gremba, Jerzy; Gałdzińska-Calik, Barbara; Wójcik-Piotrowicz, Karolina; Thor, Piotr J

    2015-01-01

    Exposure to artificial radio frequency electromagnetic fields (EMFs) has increased significantly in recent decades. Therefore, there is a growing scientific and social interest in its influence on health, even upon exposure significantly below the applicable standards. The intensity of electromagnetic radiation in human environment is increasing and currently reaches astronomical levels that had never before experienced on our planet. The most influential process of EMF impact on living organisms, is its direct tissue penetration. The current established standards of exposure to EMFs in Poland and in the rest of the world are based on the thermal effect. It is well known that weak EMF could cause all sorts of dramatic non-thermal effects in body cells, tissues and organs. The observed symptoms are hardly to assign to other environmental factors occurring simultaneously in the human environment. Although, there are still ongoing discussions on non-thermal effects of EMF influence, on May 31, 2011--International Agency for Research on Cancer (IARC)--Agenda of World Health Organization (WHO) has classified radio electromagnetic fields, to a category 2B as potentially carcinogenic. Electromagnetic fields can be dangerous not only because of the risk of cancer, but also other health problems, including electromagnetic hypersensitivity (EHS). Electromagnetic hypersensitivity (EHS) is a phenomenon characterized by the appearance of symptoms after exposure of people to electromagnetic fields, generated by EHS is characterized as a syndrome with a broad spectrum of non-specific multiple organ symptoms including both acute and chronic inflammatory processes located mainly in the skin and nervous systems, as well as in respiratory, cardiovascular systems, and musculoskeletal system. WHO does not consider the EHS as a disease-- defined on the basis of medical diagnosis and symptoms associated with any known syndrome. The symptoms may be associated with a single source of EMF

  18. Biological effect of radiation on human

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yun Sil; Cho, Chul Koo; Lee, Su Jae [and others

    2000-04-01

    1. Adaptive response when 0.01 Gy was preirradiated before high challenging dose is induced in normal cell types such normal lymphocytes, primary keratinocytes, and L929 fibroblast cells but not in neoplastic cells such as L5178Y lymphoma cells, EL-4 lymphoma cells and 308 papilloma cells. 2. Heat shock protein (HSP) 25 and inducible HSP70 is responsible for the induction of adaptive response and radioresistance - cell cycle regulation, antiapoptotic molecule and PKC activation were involved. 3. Apoptosis was induced at most 5. hrs after irradiation in primary keratinocytes, in v-rasHa transformed keratinocytes, the maximum interval was 16 hrs, and in 308 papilloma cells, the maximum was 48 hrs. 4. PKC response by radiation is correlated with induction of apoptosis. 5. Rapid induction PKCdelta in primary keratinocytes and no response of PKC epsilon may involved in radiation induced apoptosis. 6. The rate of resorption was increased when radiation was given at 2.5 days after gestation. Early death including foetal death were highly expressed when radiation was given at 7.5 days after gestation. There are no difference in incidence of late death including embryonic death. 7. 2 Gy is the most effective dose in radiation induced teratogenesis in mouse model. 8. Growth retardation and small head was present when radiation was given at 5.5, 7.5, 11.5 and 15.5 days after gestation and small head showed high incidence at 11.5 days after gestation. 9. External malformation, internal malformation and skeletal malformation was induced when radiation was given at 7.5 days after gestation. 10. OGG1-mutated cells induced radiosensitive by G2/M cell cycle arrest. 11. Radiation induced G2/M phase cell cycle and correlated with radiosensitivity. 12. PKCalpha induced differentiation. 13. Radiation exposed cells showed carcinogenic effect. 14. Organ specific radiosensitivity was shown and protein expression was involved.

  19. Drift correction for accurate PRF-shift MR thermometry during mild hyperthermia treatments with MR-HIFU.

    Science.gov (United States)

    Bing, Chenchen; Staruch, Robert M; Tillander, Matti; Köhler, Max O; Mougenot, Charles; Ylihautala, Mika; Laetsch, Theodore W; Chopra, Rajiv

    2016-09-01

    There is growing interest in performing hyperthermia treatments with clinical magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) therapy systems designed for tissue ablation. During hyperthermia treatment, however, due to the narrow therapeutic window (41-45 °C), careful evaluation of the accuracy of proton resonant frequency (PRF) shift MR thermometry for these types of exposures is required. The purpose of this study was to evaluate the accuracy of MR thermometry using a clinical MR-HIFU system equipped with a hyperthermia treatment algorithm. Mild heating was performed in a tissue-mimicking phantom with implanted temperature sensors using the clinical MR-HIFU system. The influence of image-acquisition settings and post-acquisition correction algorithms on the accuracy of temperature measurements was investigated. The ability to achieve uniform heating for up to 40 min was evaluated in rabbit experiments. Automatic centre-frequency adjustments prior to image-acquisition corrected the image-shifts in the order of 0.1 mm/min. Zero- and first-order phase variations were observed over time, supporting the use of a combined drift correction algorithm. The temperature accuracy achieved using both centre-frequency adjustment and the combined drift correction algorithm was 0.57° ± 0.58 °C in the heated region and 0.54° ± 0.42 °C in the unheated region. Accurate temperature monitoring of hyperthermia exposures using PRF shift MR thermometry is possible through careful implementation of image-acquisition settings and drift correction algorithms. For the evaluated clinical MR-HIFU system, centre-frequency adjustment eliminated image shifts, and a combined drift correction algorithm achieved temperature measurements with an acceptable accuracy for monitoring and controlling hyperthermia exposures.

  20. Third eye, the biological effects; 3. oeil, les effets biologiques

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2004-02-01

    The discovery of a third kind of photo-receptor cell in the human eye has permitted to better understand the biological effects of lighting, not only on the vision, but also on some nervous processes, like emotion, mood, stress, biological clock, etc.. This additional dimension has led the engineers of Philips Lighting company to launch a new indoor lighting concept named 'Carpe Diem'. This concept adapts both the illuminance and the color of a lighting system according to the type of work and to the expected stimulating effect. (J.S.)

  1. Biological effect of penetration controlled irradiation with ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Atsushi; Shimizu, Takashi; Kikuchi, Masahiro; Kobayashi, Yasuhiko; Watanabe, Hiroshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Yamashita, Takao

    1997-03-01

    To investigate the effect of local irradiation with ion beams on biological systems, technique for penetration controlled irradiation has been established. The range in a target was controlled by changing the distance from beam window in the atmosphere, and could be controlled linearly up to about 31 {mu}m in biological material. In addition, the effects of the penetration controlled irradiations with 1.5 MeV/u C and He ions were examined using tobacco pollen. The increased frequency of leaky pollen produced by ion beams suggests that the efficient pollen envelope damages would be induced at the range-end of ion beams. (author)

  2. Experimental Validation of a Novel MRI-Compatible HIFU Device for the Treatment of Superficial Venous Insufficiency

    Science.gov (United States)

    Salomir, Rares; Pichardo, Samuel; Petrusca, Lorena; Angel, Yves; Lacoste, François; Chapelon, Jean-Yves

    2007-05-01

    A novel High Intensity Focused Ultrasound (HIFU) probe has been designed for minimally-invasive treatment of valvular dysfunction in the saphenous vein, which is known to be the cause of superficial venous insufficiency (SVI) and varicose veins. Treating SVI with HIFU is possible, since venous tissue undergoes localized partial shrinkage when subjected to high temperature elevation. In a previous study in vitro we demonstrated that diameter shrinkage should be sufficient to restore valvular function, as this is done in the more aggressive approach known as external valvuloplasty. Numerical optimization using fast simulations of pressure field have led to a non-spherically shaped probe design with two HIFU elements that focus ultrasound uniformly over a line of length 7 mm, at a depth of 15 mm from the skin. A MR-compatible prototype of the probe has been constructed and this was characterized 1). by electroacustical mapping of the pressure field in water, and 2). by fast, high resolution MR thermal mapping ex vivo on fresh meat samples. Results were in good agreement with those predicted by an analytical approach and numerical simulations. Available experimental data suggest that a short sonication (less than 10 sec duration) should permit sufficient temperature elevation to obtain vein shrinkage. Further studies will be performed on surgically excised samples of human veins under MR thermal mapping in order to determine the optimal sonication parameters (duration and power level).

  3. Biological Effects of Laser Radiation. Volume II. Review of Our Studies on Biological Effects of Laser Radiation-1965-1971.

    Science.gov (United States)

    1978-10-17

    Ben Fine. 8. W.T. Ham,Jr., R.C. Williams, H.A. Mueller, Du Pont Guerry,III, A.M. Clarke and W.J. Geeraets, Effects of Laser Radiation on the Mammalian...and Applications course, Polytechnic Institute of Brooklyn Graduate Center, September, 1969 35. S. Fine and E. Klein, "Biological Effects of Laser

  4. Plasma effects in electromagnetic field interaction with biological tissue

    Science.gov (United States)

    Sharma, R. P.; Batra, Karuna; Excell, Peter S.

    2011-02-01

    Theoretical analysis is presented of the nonlinear behavior of charge carriers in biological tissue under the influence of varying low-intensity electromagnetic (EM) field. The interaction occurs because of the nonlinear force arising due to the gradient of the EM field intensity acting on free electrons in the conduction band of proteins in metabolically active biological cell membrane receptors leading to a redistribution of charge carriers. Field dependence of the resulting dielectric constant is investigated by a suitable modification to include an additional electronic contribution term to the three-term Debye model. The exogenous EM field propagating in this nonlinear cellular medium satisfies the nonlinear Schrödinger equation and can be affected significantly. Resulting field effect can be substantially augmented and effective rectification/demodulation can occur. Possible implications of this modification on biological processes in white and grey matter are discussed.

  5. Challenges in Analyzing the Biological Effects of Resveratrol

    DEFF Research Database (Denmark)

    Erdogan, Cihan Süleyman; Vang, Ole

    2016-01-01

    The suggested health effects (e.g., disease prevention) of dietary bioactive compounds such as resveratrol are challenging to prove in comparison to man-made drugs developed for therapeutic purposes. Dietary bioactive compounds have multiple cellular targets and therefore have a variety of biolog...

  6. Adaptation hypothesis of biological effectiveness of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kudritsky, Yu.K.; Georgievsky, A.B.; Karpov, V.I.

    1993-12-31

    The adoptation hypothesis of biological effectiveness of ionizing radiations is based on the recognition of the invariability of general biological laws for radiobiology and on the comprehension of life evolution regularities and axiomatic principles of environment and biota unity. The ionizing radiation factor is essential for life which could not exist beyond the radiation field. The possibility of future development of the adaptation hypothesis serves as a basis for it`s transformation into the theoretical foundation of radiobiology. This report discusses the aspects of the adaptation theory.

  7. Examining the nature of retrocausal effects in biology and psychology

    Science.gov (United States)

    Mossbridge, Julia

    2017-05-01

    Multiple laboratories have reported physiological and psychological changes associated with future events that are designed to be unpredictable by normal sensory means. Such phenomena seem to be examples of retrocausality at the macroscopic level. Here I will discuss the characteristics of seemingly retrocausal effects in biology and psychology, specifically examining a biological and a psychological form of precognition, predictive anticipatory activity (PAA) and implicit precognition. The aim of this examination is to offer an analysis of the constraints posed by the characteristics of macroscopic retrocausal effects. Such constraints are critical to assessing any physical theory that purports to explain these effects. Following a brief introduction to recent research on PAA and implicit precognition, I will describe what I believe we have learned so far about the nature of these effects, and conclude with a testable, yet embryonic, model of macroscopic retrocausal phenomena.

  8. Effect of biologic agents on radiographic progression of rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Gabriel J Tobón

    2010-08-01

    Full Text Available Gabriel J Tobón1, Alain Saraux1,2, Valérie Devauchelle-Pensec1,21Immunology Laboratory, Morvan Hospital, Université de Bretagne Occidentale, Brest, France; 2Rheumatology Unit, Hôpital de la Cavale Blanche, CHU Brest, FranceAbstract: The treatment of rheumatoid arthritis (RA has benefited over the last few years from the introduction of biologic agents whose development was based on new insights into the immunological factors involved in the pathogenesis of RA and the development of joint damage. These biological agents have been proven effective in RA patients with inadequate responses to synthetic disease-modifying antirheumatic drugs (DMARDs. Preventing joint damage is now the primary goal of RA treatment, and guidelines exist for the follow-up of joint abnormalities. Most biologic agents produced high clinical and radiological response rates in patients with established or recent-onset RA. Thus, for the first time, obtaining a remission is a reasonable treatment goal in RA patients. Factors that are crucial to joint damage control are: early initiation of DMARDs, use of intensive treatments including biological agents, and close monitoring of clinical disease activity and radiographic progression. However, some patients remain unresponsive to all available treatments and continue to experience joint damage progression. A major objective now is to identify patients at high risk for severe joint damage, in order to tailor the treatment regimen to their specific needs.Keywords: rheumatoid arthritis, radiographic progression, biologics

  9. [Effects of high intensity focused ultrasound with SonoVue on blood vessels pathological examinations].

    Science.gov (United States)

    Qin, Yan; Bai, Jin; Li, Faqi; Wang, Zhibiao

    2010-12-01

    The injury of tumor blood vessels will break up the nutrition supply for the tumor. In this paper, we investigated the effects exerted by high intensity focused ultrasound (HIFU) combined with ultrasound microbubble agent on blood vessels. Ultrasound diagnosis was used to find the goat hepatic blood vessels each being approximately 3mm in diameter. HIFU was focused on the blood vessels. The acoustic power was 250W; HIFU irradiating Mode was line scan (the length of the line: 10 mm; speed: 3 mm/s; irradiating time: 30s). In the experimental group, 0.03 ml/kg SonoVue was injected into the goat before HIFU irradiation,while normal saline was given to the control group. The goats were killed at 24h after HIFU irradiation, then goat liver tissues and blood vessels of target area were taken out. HE staining and Victoria's blue and Ponceau's staining of tissue section showed that the endothelial cells of blood vessels dropped off and became necrosed, and the continuity of blood vessels was interrupted. HIFU combined with SonoVue will damage large blood vessels on HIFU focus, but there is no evident discrepancy between the group with SonoVue and the group without SonoVue.

  10. Keratorefractive Effect of High Intensity Focused Ultrasound Keratoplasty on Rabbit Eyes

    Directory of Open Access Journals (Sweden)

    Zhiyu Du

    2016-01-01

    Full Text Available Purpose. To evaluate high intensity focused ultrasound (HIFU as an innovation and noninvasive technique to correct presbyopia by altering corneal curvature in the rabbit eye. Methods. Eighteen enucleated rabbit eyes were treated with a prototype HIFU keratoplasty. According to the therapy power, these eyes were divided three groups: group 1 (1 W, group 2 (2 W, and group 3 (3 W. The change in corneal power was quantified by a Sirius Scheimpflug camera. Light microscopy (LM and transmission electron microscopy (TEM were performed to determine the effect on the corneal stroma. Results. In the treated eyes, the corneal curvature increases from 49.42 ± 0.30 diopters (D and 48.00 ± 1.95 D before procedure to 51.37 ± 1.11 D and 57.00 ± 1.84 D after HIFU keratoplasty application in groups 1 and 3, respectively. The major axis and minor axis of the focal region got longer when the powers of the HIFU got increased; the difference was statistically significant (p<0.05. LM and TEM showed HIFU-induced shrinkage of corneal stromal collagen with little disturbance to the underlying epithelium. Conclusions. We have preliminarily exploited HIFU to establish a new technique for correcting presbyopia. HIFU keratoplasty will be a good application prospect for treating presbyopia.

  11. Predictive modeling of nanomaterial exposure effects in biological systems

    Directory of Open Access Journals (Sweden)

    Liu X

    2013-09-01

    Full Text Available Xiong Liu,1 Kaizhi Tang,1 Stacey Harper,2 Bryan Harper,2 Jeffery A Steevens,3 Roger Xu1 1Intelligent Automation, Inc., Rockville, MD, USA; 2Department of Environmental and Molecular Toxicology, School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, OR, USA; 3ERDC Environmental Laboratory, Vicksburg, MS, USA Background: Predictive modeling of the biological effects of nanomaterials is critical for industry and policymakers to assess the potential hazards resulting from the application of engineered nanomaterials. Methods: We generated an experimental dataset on the toxic effects experienced by embryonic zebrafish due to exposure to nanomaterials. Several nanomaterials were studied, such as metal nanoparticles, dendrimer, metal oxide, and polymeric materials. The embryonic zebrafish metric (EZ Metric was used as a screening-level measurement representative of adverse effects. Using the dataset, we developed a data mining approach to model the toxic endpoints and the overall biological impact of nanomaterials. Data mining techniques, such as numerical prediction, can assist analysts in developing risk assessment models for nanomaterials. Results: We found several important attributes that contribute to the 24 hours post-fertilization (hpf mortality, such as dosage concentration, shell composition, and surface charge. These findings concur with previous studies on nanomaterial toxicity using embryonic zebrafish. We conducted case studies on modeling the overall effect/impact of nanomaterials and the specific toxic endpoints such as mortality, delayed development, and morphological malformations. The results show that we can achieve high prediction accuracy for certain biological effects, such as 24 hpf mortality, 120 hpf mortality, and 120 hpf heart malformation. The results also show that the weighting scheme for individual biological effects has a significant influence on modeling the overall impact of

  12. Calibration of HIFU intensity fields measured using an infra-red camera

    Science.gov (United States)

    Shaw, A.; Khokhlova, V.; Bobkova, S.; Gavrilov, L.; Hand, J.

    2011-02-01

    A trend in HIFU technologies is to use 2D phased arrays that offer electronic steering of a single focus and formation of patterns of multiple foci. Conventional methods to characterize array fields using scanned hydrophone would be prohibitively slow given the potentially large number of focusing conditions. An alternative technique for rapid qualitative assessment of intensity distributions was recently developed. The method is based on infrared camera measurements of the temperature rises induced by low amplitude short ultrasonic bursts in a thin absorber. Here, the method is extended to estimate the absolute values of intensity in a field of a 2D 1-MHz randomized phased array. Two approaches were implemented. In the first approach it was assumed that the measured temperature rise at the surface of the absorber is proportional to the free field intensity. The second approach correlated the temperature rise measured in an absorber and calculated from the modelled acoustic field and the heat transfer equation. Corresponding correction factors between the free field intensity and temperature was obtained and introduced in the conversion of temperature images to intensity. Free field distributions in water and focusing through ribs were recorded and simulated. Good correlation between the measured and modeled results in both spatial distributions and the absolute values of intensity was demonstrated.

  13. Linking exposure to environmental pollutants with biological effects

    DEFF Research Database (Denmark)

    Sørensen, Mette; Autrup, Herman; Møller, Peter

    2003-01-01

    Exposure to ambient air pollution has been associated with cancer. Ambient air contains a complex mixture of toxics, including particulate matter (PM) and benzene. Carcinogenic effects of PM may relate both to the content of PAH and to oxidative DNA damage generated by transition metals, benzene......, metabolism and inflammation. By means of personal monitoring and biomarkers of internal dose, biologically effective dose and susceptibility, it should be possible to characterize individual exposure and identify air pollution sources with relevant biological effects. In a series of studies, individual...... breaks, base oxidation, 8-oxodG and PAH bulky adducts in lymphocytes, markers of oxidative stress in plasma and genotypes of glutathione transferases (GSTs) and NADPH:quinone reductase (NQO1). With respect to benzene, the main result indicates that DNA base oxidation is correlated with PMA excretion...

  14. Linking exposure to environmental pollutants with biological effects

    DEFF Research Database (Denmark)

    Sørensen, Mette; Autrup, Herman; Møller, Peter

    2003-01-01

    Exposure to ambient air pollution has been associated with cancer. Ambient air contains a complex mixture of toxics, including particulate matter (PM) and benzene. Carcinogenic effects of PM may relate both to the content of PAH and to oxidative DNA damage generated by transition metals, benzene......, metabolism and inflammation. By means of personal monitoring and biomarkers of internal dose, biologically effective dose and susceptibility, it should be possible to characterize individual exposure and identify air pollution sources with relevant biological effects. In a series of studies, individual....... With respect to exposure to PM, biomarkers of oxidative damage showed significant positive association with the individual exposure. Thus, 8-oxodG in lymphocyte DNA and markers of oxidative damage to lipids and protein in plasma associated with PM(2.5) exposure. Several types of DNA damage showed seasonal...

  15. Biological effects of exposure to magnetic resonance imaging: an overview

    Directory of Open Access Journals (Sweden)

    Formica Domenico

    2004-04-01

    Full Text Available Abstract The literature on biological effects of magnetic and electromagnetic fields commonly utilized in magnetic resonance imaging systems is surveyed here. After an introduction on the basic principles of magnetic resonance imaging and the electric and magnetic properties of biological tissues, the basic phenomena to understand the bio-effects are described in classical terms. Values of field strengths and frequencies commonly utilized in these diagnostic systems are reported in order to allow the integration of the specific literature on the bio-effects produced by magnetic resonance systems with the vast literature concerning the bio-effects produced by electromagnetic fields. This work gives an overview of the findings about the safety concerns of exposure to static magnetic fields, radio-frequency fields, and time varying magnetic field gradients, focusing primarily on the physics of the interactions between these electromagnetic fields and biological matter. The scientific literature is summarized, integrated, and critically analyzed with the help of authoritative reviews by recognized experts, international safety guidelines are also cited.

  16. Advances in the biological effects of terahertz wave radiation.

    Science.gov (United States)

    Zhao, Li; Hao, Yan-Hui; Peng, Rui-Yun

    2014-01-01

    The terahertz (THz) band lies between microwave and infrared rays in wavelength and consists of non-ionizing radiation. Both domestic and foreign research institutions, including the army, have attached considerable importance to the research and development of THz technology because this radiation exhibits both photon-like and electron-like properties, which grant it considerable application value and potential. With the rapid development of THz technology and related applications, studies of the biological effects of THz radiation have become a major focus in the field of life sciences. Research in this field has only just begun, both at home and abroad. In this paper, research progress with respect to THz radiation, including its biological effects, mechanisms and methods of protection, will be reviewed.

  17. Advances in the biological effects of terahertz wave radiation

    Institute of Scientific and Technical Information of China (English)

    Li Zhao; Yan-Hui Hao; Rui-Yun Peng

    2014-01-01

    The terahertz (THz) band lies between microwave and infrared rays in wavelength and consists of non-ionizing radiation. Both domestic and foreign research institutions, including the army, have attached considerable importance to the research and development of THz technology because this radiation exhibits both photon-like and electron-like properties, which grant it considerable application value and potential. With the rapid development of THz technology and related applications, studies of the biological effects of THz radiation have become a major focus in the field of life sciences. Research in this field has only just begun, both at home and abroad. In this paper, research progress with respect to THz radiation, including its biological effects, mechanisms and methods of protection, will be reviewed.

  18. On Quantum Effects in a Theory of Biological Evolution

    Science.gov (United States)

    Martin-Delgado, M. A.

    2012-01-01

    We construct a descriptive toy model that considers quantum effects on biological evolution starting from Chaitin's classical framework. There are smart evolution scenarios in which a quantum world is as favorable as classical worlds for evolution to take place. However, in more natural scenarios, the rate of evolution depends on the degree of entanglement present in quantum organisms with respect to classical organisms. If the entanglement is maximal, classical evolution turns out to be more favorable. PMID:22413059

  19. On quantum effects in a theory of biological evolution.

    Science.gov (United States)

    Martin-Delgado, M A

    2012-01-01

    We construct a descriptive toy model that considers quantum effects on biological evolution starting from Chaitin's classical framework. There are smart evolution scenarios in which a quantum world is as favorable as classical worlds for evolution to take place. However, in more natural scenarios, the rate of evolution depends on the degree of entanglement present in quantum organisms with respect to classical organisms. If the entanglement is maximal, classical evolution turns out to be more favorable.

  20. Controlling the biological effects of spermine using a synthetic receptor.

    Science.gov (United States)

    Vial, Laurent; Ludlow, R Frederick; Leclaire, Julien; Pérez-Fernandez, Ruth; Otto, Sijbren

    2006-08-09

    Polyamines play an important role in biology, yet their exact function in many processes is poorly understood. Artificial host molecules capable of sequestering polyamines could be useful tools for studying their cellular function. However, designing synthetic receptors with affinities sufficient to compete with biological polyamine receptors remains a huge challenge. Binding affinities of synthetic hosts are typically separated by a gap of several orders of magnitude from those of biomolecules. We now report that a dynamic combinatorial selection approach can deliver a synthetic receptor that bridges this gap. The selected receptor binds spermine with a dissociation constant of 22 nM, sufficient to remove it from its natural host DNA and reverse some of the biological effects of spermine on the nucleic acid. In low concentrations, spermine induces the formation of left-handed DNA, but upon addition of our receptor, the DNA reverts back to its right-handed form. NMR studies and computer simulations suggest that the spermine complex has the form of a pseudo-rotaxane. The spermine receptor is a promising lead for the development of therapeutics or molecular probes for elucidating spermine's role in cell biology.

  1. Effect of Ceramic Scaffold Architectural Parameters on Biological Response.

    Science.gov (United States)

    Gariboldi, Maria Isabella; Best, Serena M

    2015-01-01

    Numerous studies have focused on the optimization of ceramic architectures to fulfill a variety of scaffold functional requirements and improve biological response. Conventional fabrication techniques, however, do not allow for the production of geometrically controlled, reproducible structures and often fail to allow the independent variation of individual geometric parameters. Current developments in additive manufacturing technologies suggest that 3D printing will allow a more controlled and systematic exploration of scaffold architectures. This more direct translation of design into structure requires a pipeline for design-driven optimization. A theoretical framework for systematic design and evaluation of architectural parameters on biological response is presented. Four levels of architecture are considered, namely (1) surface topography, (2) pore size and geometry, (3) porous networks, and (4) macroscopic pore arrangement, including the potential for spatially varied architectures. Studies exploring the effect of various parameters within these levels are reviewed. This framework will hopefully allow uncovering of new relationships between architecture and biological response in a more systematic way as well as inform future refinement of fabrication techniques to fulfill architectural necessities with a consideration of biological implications.

  2. Effect of Ceramic Scaffold Architectural Parameters on Biological Response

    Directory of Open Access Journals (Sweden)

    Maria Isabella eGariboldi

    2015-10-01

    Full Text Available Numerous studies have focused on the optimization of ceramic architectures to fulfill a variety of scaffold functional requirements and improve biological response. Conventional fabrication techniques, however, do not allow for the production of geometrically controlled, reproducible structures and often fail to allow the independent variation of individual geometric parameters. Current developments in additive manufacturing technologies suggest that 3D printing will allow a more controlled and systematic exploration of scaffold architectures. This more direct translation of design into structure requires a pipeline for design-driven optimization. A theoretical framework for systematic design and evaluation of architectural parameters on biological response is presented. Four levels of architecture are considered, namely (1 surface topography, (2 pore size and geometry, (3 porous networks and (4 macroscopic pore arrangement, including the potential for spatially varied architectures. Studies exploring the effect of various parameters within these levels are reviewed. This framework will hopefully allow uncovering of new relationships between architecture and biological response in a more systematic way, as well as inform future refinement of fabrication techniques to fulfill architectural necessities with a consideration of biological implications.

  3. Effect of pH on biological phosphorus uptake.

    Science.gov (United States)

    Serralta, J; Ferrer, J; Borrás, L; Seco, A

    2006-12-05

    An anaerobic aerobic laboratory scale sequencing batch reactor (SBR) was operated to study the effect of pH on enhanced biological phosphorus removal. Seven steady states were achieved under different operating conditions. In all of them, a slight variation in the pH value was observed during anaerobic phase. However, pH rose significantly during aerobic phase. The increase observed was due to phosphorus uptake and carbon dioxide stripping. When pH was higher than 8.2-8.25 the phosphorus uptake rate clearly decreased. The capability of Activated Sludge Model No. 2d (ASM2d) and Biological Nutrient Removal Model No. 1 (BNRM1) to simulate experimental results was evaluated. Both models successfully characterized the enhanced biological phosphorus removal performance of the SBR. Furthermore, BNRM1 also reproduced the pH variations observed and the decrease in the phosphorus uptake rate. This model includes a switch function in the kinetic expressions to represent the pH inhibition in biological processes. The pH inhibition constants related to polyphosphate storage process were obtained by adjusting model predictions to measured phosphorus concentrations. On the other hand, pH inhibition should be included in ASM2d to accurately simulate experimental phosphorus evolution observed in an A/O SBR.

  4. Case Report: Use of reinforced buccal mucosa graft over gracilis muscle flap in management of post high intensity focused ultrasound (HIFU) rectourethral fistula

    Science.gov (United States)

    Jai, Shrikant; Ganpule, Arvind; Singh, Abhishek; Vijaykumar, Mohankumar; Bopaiah, Vinod; Sabnis, Ravindra; Desai, Mahesh

    2017-01-01

    High intensity focused ultrasound (HIFU) has come forward as alternative treatment for carcinoma of the prostate. Though minimally invasive,HIFUhas potential side effects. Urethrorectal fistula is one such rare side effect. Management of these fistulas has been described by Vanni et al. This case report describes points of technique that will help successful management of resilient rectourethral fistula. Urinary and faecal diversion in the form of suprapubic catheter and colostomy is vital. Adequate time between stoma formation, fistula closure and then finally stoma closure is needed. Lithotomy position and perineal approach gives best exposure to the fistula. The rectum should be dissected 2cm above the fistula; this aids in tension free closure of the rectal defect. Similarly buccal mucosal graft was used on the urethra to achieve tension free closure. A good vascular pedicle gracilis muscle flap is used to interpose between the two repairs. This not only provides a physical barrier but also provides a vascular bed for BMG uptake. Perfect haemostasis is essential, as any collection may become a site of infection thus compromising results.  We strongly recommend rectourethral fistula be directly repaired with gracilis muscle flap with reinforced buccal mucosa graft without attempting any less invasive repairs because the “first chance is the best chance”. PMID:28299181

  5. 高强聚焦超声(HIFU)加热活体组织中的温度分布%Temperature distribution in vivo tissues heated by high intensity focused ultrasound(HIFU)

    Institute of Scientific and Technical Information of China (English)

    钱祖文

    2010-01-01

    在高强聚焦超声(HIFU)加热的情况下,利用多针射频(RF)测温装置测量活体组织内的温度分布,结果表明,温度梯度依赖于局部温度,温度越商,梯度越大.此外,本文还研究了血流对温度梯度的影响,结果似乎证实了理论预测,即血流(或血液灌注)减缓了温度(梯度)的变化.

  6. Intuitive biological thought: Developmental changes and effects of biology education in late adolescence.

    Science.gov (United States)

    Coley, John D; Arenson, Melanie; Xu, Yian; Tanner, Kimberly D

    2017-02-01

    A large body of cognitive research has shown that people intuitively and effortlessly reason about the biological world in complex and systematic ways. We addressed two questions about the nature of intuitive biological reasoning: How does intuitive biological thinking change during adolescence and early adulthood? How does increasing biology education influence intuitive biological thinking? To do so, we developed a battery of measures to systematically test three components of intuitive biological thought: anthropocentric thinking, teleological thinking and essentialist thinking, and tested 8th graders and university students (both biology majors, and non-biology majors). Results reveal clear evidence of persistent intuitive reasoning among all populations studied, consistent but surprisingly small differences between 8th graders and college students on measures of intuitive biological thought, and consistent but again surprisingly small influence of increasing biology education on intuitive biological reasoning. Results speak to the persistence of intuitive reasoning, the importance of taking intuitive knowledge into account in science classrooms, and the necessity of interdisciplinary research to advance biology education. Further studies are necessary to investigate how cultural context and continued acquisition of expertise impact intuitive biology thinking.

  7. Biological effects from electromagnetic field exposure and public exposure standards.

    Science.gov (United States)

    Hardell, Lennart; Sage, Cindy

    2008-02-01

    During recent years there has been increasing public concern on potential health risks from power-frequency fields (extremely low frequency electromagnetic fields; ELF) and from radiofrequency/microwave radiation emissions (RF) from wireless communications. Non-thermal (low-intensity) biological effects have not been considered for regulation of microwave exposure, although numerous scientific reports indicate such effects. The BioInitiative Report is based on an international research and public policy initiative to give an overview of what is known of biological effects that occur at low-intensity electromagnetic fields (EMFs) exposure. Health endpoints reported to be associated with ELF and/or RF include childhood leukaemia, brain tumours, genotoxic effects, neurological effects and neurodegenerative diseases, immune system deregulation, allergic and inflammatory responses, breast cancer, miscarriage and some cardiovascular effects. The BioInitiative Report concluded that a reasonable suspicion of risk exists based on clear evidence of bioeffects at environmentally relevant levels, which, with prolonged exposures may reasonably be presumed to result in health impacts. Regarding ELF a new lower public safety limit for habitable space adjacent to all new or upgraded power lines and for all other new constructions should be applied. A new lower limit should also be used for existing habitable space for children and/or women who are pregnant. A precautionary limit should be adopted for outdoor, cumulative RF exposure and for cumulative indoor RF fields with considerably lower limits than existing guidelines, see the BioInitiative Report. The current guidelines for the US and European microwave exposure from mobile phones, for the brain are 1.6 W/Kg and 2 W/Kg, respectively. Since use of mobile phones is associated with an increased risk for brain tumour after 10 years, a new biologically based guideline is warranted. Other health impacts associated with exposure to

  8. Prostate cancer transrectal HIFU ablation: detection of local recurrences using T2-weighted and dynamic contrast-enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Rouviere, Olivier; Lyonnet, Denis [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urinary and Vascular Radiology, Lyon (France); Universite de Lyon, Lyon (France); Universite de Lyon 1, Faculte de medecine Lyon Nord, Lyon (France); Inserm, U556, Lyon (France); Girouin, Nicolas; Glas, Ludivine; Ben Cheikh, Alexandre [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urinary and Vascular Radiology, Lyon (France); Universite de Lyon, Lyon (France); Universite de Lyon 1, Faculte de medecine Lyon Nord, Lyon (France); Gelet, Albert [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urology, Lyon (France); Inserm, U556, Lyon (France); Mege-Lechevallier, Florence [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Pathology, Lyon (France); Rabilloud, Muriel [Hospices Civils de Lyon, Department of Biostatistics, Lyon (France); Universite de Lyon 1, UMR CNRS, Laboratoire Biostatistiques-Sante, Pierre-Benite (France); Chapelon, Jean-Yves [Inserm, U556, Lyon (France)

    2010-01-15

    The objective was to evaluate T2-weighted (T2w) and dynamic contrast-enhanced (DCE) MRI in detecting local cancer recurrences after prostate high-intensity focused ultrasound (HIFU) ablation. Fifty-nine patients with biochemical recurrence after prostate HIFU ablation underwent T2-weighted and DCE MRI before transrectal biopsy. For each patient, biopsies were performed by two operators: operator 1 (blinded to MR results) performed random and colour Doppler-guided biopsies (''routine biopsies''); operator 2 obtained up to three cores per suspicious lesion on MRI (''targeted biopsies''). Seventy-seven suspicious lesions were detected on DCE images (n=52), T2w images (n=2) or both (n=23). Forty patients and 41 MR lesions were positive at biopsy. Of the 36 remaining MR lesions, 20 contained viable benign glands. Targeted biopsy detected more cancers than routine biopsy (36 versus 27 patients, p=0.0523). The mean percentages of positive cores per patient and of tumour invasion of the cores were significantly higher for targeted biopsies (p<0.0001). The odds ratios of the probability of finding viable cancer and viable prostate tissue (benign or malignant) at targeted versus routine biopsy were respectively 3.35 (95% CI 3.05-3.64) and 1.38 (95% CI 1.13-1.63). MRI combining T2-weighted and DCE images is a promising method for guiding post-HIFU biopsy towards areas containing recurrent cancer and viable prostate tissue. (orig.)

  9. Biological effects of low level exposures to chemicals and radiation

    Energy Technology Data Exchange (ETDEWEB)

    Calabrese, E.J. (ed.)

    1992-01-01

    In May 1990 a group of scientists representing several federal agencies, the International Society of Regulatory Toxicology and Pharmacology, the private sector, and academia met to develop a strategy to encourage the study of the biological effects of low level exposures (BELLE) to chemical agents and radioactivity. A workshop was held in 1991 with seven invited speakers focusing on the toxicological implications of biological adaptations. The selection of topics and speakers was designed to consider critically the concept of hormesis, not only in a broad, conceptual manner, but also at the molecular and biochemical levels. These presentations offered a complementary perspective on the diverse range of molecular mechanisms that can become activated at low levels of toxicant exposure. In addition to chemical toxicology research, an overview of current research on Effects of low-dose radiation on the immune response' was presented as well as Cellular adaptation as an important response during chemical carcinogenesis'. The final presentation was devoted to biostatistical considerations when designing studies that address issues associated with the biological responses to low doses of chemicals and radiation, as well as issues in interpretation of the findings from such studies.

  10. A feasibility study of soft embalmed human breast tissue for preclinical trials of HIFU- preliminary results

    Science.gov (United States)

    Joy, Joyce; Yang, Yang; Purdie, Colin; Eisma, Roos; Melzer, Andreas; Cochran, Sandy; Vinnicombe, Sarah

    2017-03-01

    Breast cancer is the commonest cancer in women in the UK, accounting for 30% of all new cancers in women, with an estimated 49,500 new cases in 20101. With the widespread negative publicity around over-diagnosis and over-treatment of low risk breast cancers, interest in the application of non-invasive treatments such as magnetic resonance imaging (MRI) guided high intensity focused ultrasound (HIFU) has increased. Development has begun of novel US transducers and platforms specifically designed for use with breast lesions, so as to improve the range of breast lesions that can be safely treated. However, before such transducers can be evaluated in patients in clinical trials, there is a need to establish their efficacy. A particular issue is the accuracy of temperature monitoring of FUS with MRI in the breast, since the presence of large amounts of surrounding fat can hinder temperature measurement. An appropriate anatomical model that imposes similar physical constraints to the breast and that responds to FUS in the same way would be extremely advantageous. The aim of this feasibility study is to explore the use of Thiel embalmed cadaveric tissue for these purposes. We report here the early results of laboratory-based experiments sonicating dissected breast samples from a Thiel embalmed soft human cadaver with high body mass index (BMI). A specially developed MRI compatible chamber and sample holder was developed to secure the sample and ensure reproducible sonications at the transducer focus. The efficacy of sonication was first studied with chicken breast and porcine tissue. The experiments were then repeated with the dissected fatty breast tissue samples from the soft-embalmed human cadavers. The sonicated Thiel breast tissue was examined histopathologically, which confirmed the absence of any discrete lesion. To investigate further, fresh chicken breast tissue was embalmed and the embalmed tissue was sonicated with the same parameters. The results confirmed the

  11. Evaluation of HIFU-induced lesion region using temperature threshold and equivalent thermal dose methods

    Science.gov (United States)

    Chang, Shihui; Xue, Fanfan; Zhou, Wenzheng; Zhang, Ji; Jian, Xiqi

    2017-03-01

    Usually, numerical simulation is used to predict the acoustic filed and temperature distribution of high intensity focused ultrasound (HIFU). In this paper, the simulated lesion volumes obtained by temperature threshold (TRT) 60 °C and equivalent thermal dose (ETD) 240 min were compared with the experimental results which were obtained by animal tissue experiment in vitro. In the simulation, the calculated model was established according to the vitro tissue experiment, and the Finite Difference Time Domain (FDTD) method was used to calculate the acoustic field and temperature distribution in bovine liver by the Westervelt formula and Pennes bio-heat transfer equation, and the non-linear characteristics of the ultrasound was considered. In the experiment, the fresh bovine liver was exposed for 8s, 10s, 12s under different power conditions (150W, 170W, 190W, 210W), and the exposure was repeated 6 times under the same dose. After the exposures, the liver was sliced and photographed every 0.2mm, and the area of the lesion region in every photo was calculated. Then, every value of the areas was multiplied by 0.2mm, and summed to get the approximation volume of the lesion region. The comparison result shows that the lesion volume of the region calculated by TRT 60 °C in simulation was much closer to the lesion volume obtained in experiment, and the volume of the region above 60 °C was larger than the experimental results, but the volume deviation was not exceed 10%. The volume of the lesion region calculated by ETD 240 min was larger than that calculated by TRT 60 °C in simulation, and the volume deviations were ranged from 4.9% to 23.7%.

  12. Biological effects of pulsating magnetic fields: role of solitons

    CERN Document Server

    Brizhik, Larissa

    2014-01-01

    In this paper, we analyze biological effects produced by magnetic fields in order to elucidate the physical mechanisms, which can produce them. We show that there is a chierarchy of such mechanisms and that the mutual interplay between them can result in the synergetic outcome. In particular, we analyze the biological effects of magnetic fields on soliton mediated charge transport in the redox processes in living organisms. Such solitons are described by nonlinear systems of equations and represent electrons that are self-trapped in alpha-helical polypeptides due to the moderately strong electron-lattice interaction. They represent a particular type of disssipativeless large polarons in low-dimensional systems. We show that the effective mass of solitons in the is different from the mass of free electrons, and that there is a resonant effect of the magnetic fields on the dynamics of solitons, and, hence, on charge transport that accompanies photosynthesis and respiration. These effects can result in non-therm...

  13. The Biological Effects of Ivabradine in Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Graziano Riccioni

    2012-04-01

    Full Text Available A large number of studies in healthy and asymptomatic subjects, as well as patients with already established cardiovascular disease (CAD have demonstrated that heart rate (HR is a very important and major independent cardiovascular risk factor for prognosis. Lowering heart rate reduces cardiac work, thereby diminishing myocardial oxygen demand. Several experimental studies in animals, including dogs and pigs, have clarified the beneficial effects of ivabradine associated with HR lowering. Ivabradine is a selective inhibitor of the hyperpolarisation activated cyclic-nucleotide-gated funny current (If involved in pacemaker generation and responsiveness of the sino-atrial node (SAN, which result in HR reduction with no other apparent direct cardiovascular effects. Several studies show that ivabradine substantially and significantly reduces major risks associated with heart failure when added to guideline-based and evidence-based treatment. However the biological effect of ivabradine have yet to be studied. This effects can appear directly on myocardium or on a systemic level improving endothelial function and modulating immune cell migration. Indeed ivabradine is an ‘open-channel’ blocker of human hyperpolarization-activated cyclic nucleotide gated channels of type-4 (hHCN4, and a ‘closed-channel’ blocker of mouse HCN1 channels in a dose-dependent manner. At endothelial level ivabradine decreased monocyte chemotactin protein-1 mRNA expression and exerted a potent anti-oxidative effect through reduction of vascular NADPH oxidase activity. Finally, on an immune level, ivabradine inhibits the chemokine-induced migration of CD4-positive lymphocytes. In this review, we discuss the biological effects of ivabradine and highlight its effects on CAD.

  14. Current research on biological effects of low-level exposures

    Energy Technology Data Exchange (ETDEWEB)

    Sagan, L.A.

    1994-12-31

    Rather substantial numbers of industrial chemicals, pharmaceuticals, and radiation display U-shaped or seemingly paradoxical dose-response relationships. A limited listing of studies providing examples of data fitting the U-shaped curve has been published. This array suggests that the U-shaped response is broadly generalizable and therefore potentially of considerable significance in the toxicological and public health domains. In fact, in 1992 and 1993, three conferences (Japan, United States, and China) were held exclusively on the topic of the biological effects of low doses of chemicals and radioactivity with articular emphasis on U-shaped curves. Substantial efforts have been made at understanding this observation.

  15. Hydrodynamic collective effects of active proteins in biological membranes

    CERN Document Server

    Koyano, Yuki; Mikhailov, Alexander S

    2016-01-01

    Lipid bilayers forming biological membranes are known to behave as viscous 2D fluids on submicrometer scales; usually they contain a large number of active protein inclusions. Recently, it has been shown [Proc. Nat. Acad. Sci. USA 112, E3639 (2015)] that such active proteins should in- duce non-thermal fluctuating lipid flows leading to diffusion enhancement and chemotaxis-like drift for passive inclusions in biomembranes. Here, a detailed analytical and numerical investigation of such effects is performed. The attention is focused on the situations when proteins are concentrated within lipid rafts. We demonstrate that passive particles tend to become attracted by active rafts and are accumulated inside them.

  16. Biological activity of selected plants with adaptogenic effect

    Directory of Open Access Journals (Sweden)

    Eva Ivanišová

    2016-05-01

    Full Text Available The aim of this study was to determine biological activity of plants with adaptogenic effect: Panax ginseng Mayer., Withania somnifera L., Eleuterococcus senticosus Rupr. et Maxim., Astragallus membranaceus Fisch. and Codonopsis pilosulae Franch. The antioxidant activity was detected by DPPH and phosphomolybdenum method, total polyphenol content with Folin – Ciocalteu reagent, flavonoids content by aluminium chloride method. The detection of antimicrobial activity was carried out by disc diffusion method against three species of Gram-negative bacteria: Escherichia coli CCM 3988, Salmonella enterica subsp. enterica CCM 3807, Yersinia enterocolitica CCM 5671 and two Gram-positive bacteria: Bacillus thuringiensis CCM 19, Stapylococcus aureus subsp. aureus CCM 2461. Results showed that plants with adaptogenic effect are rich for biologically active substances. The highest antioxidant activity by DPPH method was determined in the sample of Eleuterococcus senticosus (3.15 mg TEAC – Trolox equivalent antioxidant capacity per g of sample and by phosphomolybdenum method in the sample of Codonopsis pilosulae (188.79 mg TEAC per g of sample. In the sample of Panax ginseng was measured the highest content of total polyphenols (8.10 mg GAE – galic acid equivalent per g of sample and flavonoids (3.41 μg QE – quercetin equivalent per g of sample. All samples also showed strong antimicrobial activity with the best results in Panax ginseng and Withania somnifera in particular for species Yersinia enterocolitica CCM 5671 and Salmonella enterica subsp. enterica CCM 3807. The analyzed species of plant with high value of biological activity can be used more in the future, not only in food, but also in cosmetics and pharmaceutical industries.

  17. Conjugated linoleic acid isomers: differences in metabolism and biological effects.

    Science.gov (United States)

    Churruca, Itziar; Fernández-Quintela, Alfredo; Portillo, Maria Puy

    2009-01-01

    The term conjugated linoleic acid (CLA) refers to a mixture of linoleic acid positional and geometric isomers, characterized by having conjugated double bonds, not separated by a methylene group as in linoleic acid. CLA isomers appear as a minor component of the lipid fraction, found mainly in meat and dairy products from cows and sheep. The most abundant isomer is cis-9,trans-11, which represents up to 80% of total CLA in food. These isomers are metabolized in the body through different metabolic pathways, but important differences, that can have physiological consequences, are observed between the two main isomers. The trans-10,cis-12 isomer is more efficiently oxidized than the cis-9,trans-11 isomer, due to the position of its double bounds. Interest in CLA arose in its anticarcinogenic action but there is an increasing amount of specific scientific literature concerning the biological effects and properties of CLA. Numerous biological effects of CLA are due to the separate action of the most studied isomers, cis-9,trans-11 and trans-10,cis-12. It is also likely that some effects are induced and/or enhanced by these isomers acting synergistically. Although the cis-9,trans-11 isomer is mainly responsible for the anticarcinogenic effect, the trans-10,cis-12 isomer reduces body fat and it is referred as the most effective isomer affecting blood lipids. As far as insulin function is concerned, both isomers seem to be responsible for insulin resistance in humans. Finally, with regard to the immune system it is not clear whether individual isomers of CLA could act similarly or differently.

  18. Hafnium oxide nanoparticles: toward an in vitro predictive biological effect?

    Science.gov (United States)

    Marill, Julie; Anesary, Naeemunnisa Mohamed; Zhang, Ping; Vivet, Sonia; Borghi, Elsa; Levy, Laurent; Pottier, Agnes

    2014-06-30

    Hafnium oxide, NBTXR3 nanoparticles were designed for high dose energy deposition within cancer cells when exposed to ionizing radiation. The purpose of this study was to assess the possibility of predicting in vitro the biological effect of NBTXR3 nanoparticles when exposed to ionizing radiation. Cellular uptake of NBTXR3 nanoparticles was assessed in a panel of human cancer cell lines (radioresistant and radiosensitive) by transmission electron microscopy. The radioenhancement of NBTXR3 nanoparticles was measured by the clonogenic survival assay. NBTXR3 nanoparticles were taken up by cells in a concentration dependent manner, forming clusters in the cytoplasm. Differential nanoparticle uptake was observed between epithelial and mesenchymal or glioblastoma cell lines. The dose enhancement factor increased with increase NBTXR3 nanoparticle concentration and radiation dose. Beyond a minimum number of clusters per cell, the radioenhancement of NBTXR3 nanoparticles could be estimated from the radiation dose delivered and the radiosensitivity of the cancer cell lines. Our preliminary results suggest a predictable in vitro biological effect of NBTXR3 nanoparticles exposed to ionizing radiation.

  19. BIOLOGICAL EFFECTS OF MICROWAVE RADIATION ON BRAIN TISSUE IN RATS

    Directory of Open Access Journals (Sweden)

    Boris Đinđić

    2003-04-01

    Full Text Available Exposure to microwave radiation induces multiple organ dysfunctions, especially in CNS.The aim of this work was investigation of biological effects of microwave radiation on rats' brain and determination of increased oxidative stress as a possible pathogenetic's mechanism.Wis tar rats 3 months old were divided in experimental (4 female and 4 male animal and control group (5 female and 4 male. This experimental group was constantly exposed to a magnetic field of 5 mG. We simulated using of mobile phones 30 min every day. The source of NIR emitted MF that was similar to mobile phones at 900 MHz. The rats were killed after 2 months. Biological effects were determined by observation of individual and collective behavior and body mass changes. Lipid per oxidation was determined by measuring quantity of malondialdehyde (MDA in brain homogenate.The animals in experimental group exposed to EMF showed les weight gain. The most important observations were changing of basic behavior models and expression of aggressive or panic behavior. The content of MDA in brain tissue is singificantly higher (1.42 times in rats exposed to electromagnetic fields (3,82±0.65 vs. control 2.69±0.42 nmol/mg proteins, p<0.01.Increased oxidative stress and lipid peroxidation after exposition in EM fields induced disorders of function and structure of brain.

  20. Linking exposure to environmental pollutants with biological effects.

    Science.gov (United States)

    Sørensen, Mette; Autrup, Herman; Møller, Peter; Hertel, Ole; Jensen, Steen Solvang; Vinzents, Peter; Knudsen, Lisbeth E; Loft, Steffen

    2003-11-01

    Exposure to ambient air pollution has been associated with cancer. Ambient air contains a complex mixture of toxics, including particulate matter (PM) and benzene. Carcinogenic effects of PM may relate both to the content of PAH and to oxidative DNA damage generated by transition metals, benzene, metabolism and inflammation. By means of personal monitoring and biomarkers of internal dose, biologically effective dose and susceptibility, it should be possible to characterize individual exposure and identify air pollution sources with relevant biological effects. In a series of studies, individual exposure to PM(2.5), nitrogen dioxide (NO(2)) and benzene has been measured in groups of 40-50 subjects. Measured biomarkers included 1-hydroxypyrene, benzene metabolites (phenylmercapturic acid (PMA) and trans-trans-muconic acid (ttMA)), 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) in urine, DNA strand breaks, base oxidation, 8-oxodG and PAH bulky adducts in lymphocytes, markers of oxidative stress in plasma and genotypes of glutathione transferases (GSTs) and NADPH:quinone reductase (NQO1). With respect to benzene, the main result indicates that DNA base oxidation is correlated with PMA excretion. With respect to exposure to PM, biomarkers of oxidative damage showed significant positive association with the individual exposure. Thus, 8-oxodG in lymphocyte DNA and markers of oxidative damage to lipids and protein in plasma associated with PM(2.5) exposure. Several types of DNA damage showed seasonal variation. PAH adduct levels, DNA strand breaks and 8-oxodG in lymphocytes increased significantly in the summer period, requiring control of confounders. Similar seasonal effects on strand breaks and expression of the relevant DNA repair genes ERCC1 and OGG1 have been reported. In the present setting, biological effects of air pollutants appear mainly related to oxidative stress via personal exposure and not to urban background levels. Future developments include personal time

  1. Arsenic in the aquatic environment - speciation and biological effects

    Energy Technology Data Exchange (ETDEWEB)

    Landner, L. [Swedish Environmental Research Group (MFG)

    1998-03-01

    The present report is a contribution to EC Commission`s undertaking to review existing EC provisions on the substances for which Sweden has been granted transitional provisions. The provisions imply that Sweden may maintain more stringent regulations on four substances until the end of 1998. The present report deals with speciation and biological effects of arsenic in three types of aquatic environments - marine water, estuarine or brackish water and freshwater. The similarity between arsenate and phosphate and the interference in phosphorylation reactions is discussed. It is clear that in Scandinavian inland waters the concentration of phosphorous is on average lower than in most inland waters in continental Europe. However, in most inland waters phosphorus is the limiting factor for phytoplankton development and eutrophication, which means that there is a clear risk for detrimental effects in the great majority of inland waters, also eutrophic waters 167 refs, 27 figs, 12 tabs. Exemption Substances Project (Directive 89/677/EEC)

  2. Modeling of biological doses and mechanical effects on bone transduction

    CERN Document Server

    Rieger, Romain; Jennane, Rachid; 10.1016/j.jtbi.2011.01.003

    2012-01-01

    Shear stress, hormones like parathyroid and mineral elements like calcium mediate the amplitude of stimulus signal which affects the rate of bone remodeling. The current study investigates the theoretical effects of different metabolic doses in stimulus signal level on bone. The model was built considering the osteocyte as the sensing center mediated by coupled mechanical shear stress and some biological factors. The proposed enhanced model was developed based on previously published works dealing with different aspects of bone transduction. It describes the effects of physiological doses variations of Calcium, Parathyroid Hormone, Nitric Oxide and Prostaglandin E2 on the stimulus level sensed by osteocytes in response to applied shear stress generated by interstitial fluid flow. We retained the metabolic factors (Parathyroid Hormone, Nitric Oxide, and Prostaglandin E2) as parameters of bone cell mechanosensitivity because stimulation/inhibition of induced pathways stimulates osteogenic response in vivo. We t...

  3. Biological effects of Echinacea purpurea on human blood cells.

    Science.gov (United States)

    Joksić, Gordana; Petrović, Sandra; Joksić, Ivana; Leskovac, Andreja

    2009-06-01

    The aim of this study was to investigate radioprotective properties of Echinacea purpurea tablets in vivo. We analysed lymphocyte chromosome aberrations (CA), micronuclei (MN), apoptosis of leukocytes and haematological parameters in a group of radiation workers who were identified as carrying dicentric chromosomes in their lymphocytes. All radiation workers were taking two 275 mg Echinacea tablets b.i.d., according to a pharmacist's recommendation. All parameters were analysed before and after the two-week treatment. At the end of the treatment lymphocyte CA frequency dropped significantly, and the number of apoptotic cells increased. The inverse lymphocyte-to-granulocyte ratio at the beginning of the study changed to normal at its end. In conclusion, biological effects observed after administration of Echinacea purpurea preparation suggest that it may be beneficial for the prevention of adverse health effects in workers exposed to ionising radiation.

  4. Late biological effects from internal and external exposure

    Energy Technology Data Exchange (ETDEWEB)

    Adams, W.H.

    1985-01-01

    Information on late biological effects of radiation was obtained from the long-term medical followup of a small population of Marshallese accidentally exposed to radioactive fallout from a thermonuclear test in 1954. Endocrine data are compatible with a sequence of nonstochastic radiation effects. The ingestion of radioisotopes of iodine produced clinical thyroid hypofunction in children, biochemical evidence of thyroid dysfunction in some adults, thyroid adenomatous module formation, and, as a possible indirect effect of thyroid damage, at least two cases of pituitary adenoma. In contrast, the only evidence of a stochastic effect has been a real increase in thyroid cancers among the more highly exposed people of Rongelap, none of whom have evidence of residual disease. While three nonthyroidal cancers which are known to be inducible in humans by external irradiation have been documented in the exposed population, three similar cancers have occurred in an unexposed comparison population of Marshallese. Nonstochastic effects of radiation exposure may be common but subtle. In the Marshallese experience the morbidity of delayed nonstochastic effects far exceeds that of the stochastic. 20 refs., 5 figs., 1 tab.

  5. Effect of Organic Loading on Rotating Biological Contactor Efficiency

    Directory of Open Access Journals (Sweden)

    Kossay K. Al-Ahmady

    2005-12-01

    Full Text Available Organic loading (weight per unit time per volume is useful for the design of rotating biological contactors (RBC and for comparison with the other processes such as activated sludge or oxidation ponds. The present study puts emphasis on the significance of this control or design parameter because it allows direct comparison of the RBC system's performance when operated under various circumstances and with different kinds of wastewater. The results of the paper proved that, the COD removal in rotating biological contactor systems is a function of the organic loading rate. However, each of the wastewater concentration and flow rate are also influence on the system efficiency but theirs impact can be combined by the effect of organic loading. The majority of COD removal (40-85 % of the total removal depending on the organic loading applied occurs in the first stages of the system. There is a strong correlation between the organic loading and the concentration of the suspended solids in the rotating biological contactor basin. At higher loadings higher concentrations noted. At a loading of about, (24 g/m2.d suspended solids were 225, 125, 35, and 25 mg/L in the first, second, third and, the fourth stage respectively. To achieve an effluent quality of (BOD < 25 mg/L, COD < 60 mg/L, the system must be operated on organic loadings of about (22 gBOD/m2.d and 65 gCOD/m2.d respectively. For nitrification process, the system must be designed to operate at organic loading of about (10 g/m2.d or less and, the reactor or basin volume should be designed to achieve a hydraulic loading of about (40 L/m2.d or less.

  6. Enhanced Biological Phosphorus Removal: Metabolic Insights and Salinity Effects

    NARCIS (Netherlands)

    Welles, L.

    2015-01-01

    Enhanced biological phosphorus removal (EBPR) is a biological process for efficient phosphate removal from wastewaters through intracellular storage of polyphosphate by polyphosphate-accumulating organisms (PAO) and subsequent removal of PAO from the system through wastage of sludge. In comparison

  7. The rise of high intensity focused ultrasound (HIFU) non-invasive therapy for solid tumors%高强聚焦超声(HIFU)无创治疗肿瘤技术的崛起

    Institute of Scientific and Technical Information of China (English)

    冯若; 朱辉; 李发琪; 苏海兵; 陈迅

    2011-01-01

    20世纪40年代,美国学者首次提出了高强聚焦超声治疗技术的概念,并进行了初步的工程和临床研究.70、80年代间,治疗肿瘤的温热疗法曾盛行一时.90年代之后,高强聚焦超声外科肿瘤治疗技术在国际上重新崛起,我国率先推出了大型高强聚焦超声肿瘤治疗系统,并成功地应用于临床治疗乳腺癌、骨肿瘤、肝癌等多种实体肿瘤.迄今,该"JC型高强聚焦超声肿瘤治疗系统"已出口到英国、意大利、西班牙、日本、韩国等许多欧亚国家,在诸如欧洲肿瘤治疗中心等20多个医疗中心运行,治疗肿瘤患者达数万例.我国持续保持着引领世界超声无创治疗技术发展的领先地位.%In the 40 years of last centry American scientists put forward a concep of high intensity focused ultrasound (HIFU) therapeutic technique and had done some technical and clinical studies. Since 90 years the HIFU surgery technique treating tumors anew rised abruptly in the world. China firstly put out a comprehensive HIFU tumor treating sistem and successfully treated many solid tumors such as breast cancer, bone tumor, liver cancer etc.. Now the treating sistem has already exported to England, Italy,Spain, Japan, Colea etc. and treated tens thousands tumor patients. In the field of noninvasive ultrasound treating tumor technique China has continually kept the leading position in the world.

  8. Biological effects due to weak magnetic field on plants

    Science.gov (United States)

    Belyavskaya, N. A.

    2004-01-01

    magnetic field may cause different biological effects at the cellular, tissue and organ levels. They may be functionally related to systems that regulate plant metabolism including the intracellular Ca 2+ homeostasis. However, our understanding of very complex fundamental mechanisms and sites of interactions between weak magnetic fields and biological systems is still incomplete and still deserve strong research efforts.

  9. [DIRECTIONALITY OF THE BIOLOGICAL EFFECT OF DRINKING WATER].

    Science.gov (United States)

    Gibert, K K; Karasev, A K; Marasanov, A V; Stekhin, A A; Iakovleva, G V

    2015-01-01

    There have been performed the studies of the dimensional parameters of peroxide associates in drinking water, per- forming regulatory functions in cellular metabolism, that determine the character of the biological response of the human body to drinking water The direction of action of peroxide associates type Σ [(HO2-(*) ... OH-(*) (H2O) tp)]q, (where (H2O) tp is an associate with the tetragonal structure (Walrafen pentamer Is ice VI), q is the degree of association p--parameter of ion coordination) on the cellular structures of the organism is associated with their quantum properties, determining the macroscopic parameters of the electron wave packets. Research has confirmed the addressness of the nonlocal entering electron to certain cellular structures of the body, which is determined by the structural similarity of centers of condensation of electrons in the cells of systems and organs of the body with the parameters of the electron wave packets in the associates. Methodology for the estimation of the orientation of biological effect of the drinking water to the systems of the body on the base of the analysis of variations in heart rhythm under non-contact influence of water on the human body and its relationship with the dimensional parameters and peroxide activity of associates in drinking water can be suggested for the implementation of screening tests for drinking water quality, taking into account both the individualfeatures of responses of body systems to drinking water and its group action.

  10. Biological vs. physical mixing effects on benthic food web dynamics.

    Directory of Open Access Journals (Sweden)

    Ulrike Braeckman

    Full Text Available Biological particle mixing (bioturbation and solute transfer (bio-irrigation contribute extensively to ecosystem functioning in sediments where physical mixing is low. Macrobenthos transports oxygen and organic matter deeper into the sediment, thereby likely providing favourable niches to lower trophic levels (i.e., smaller benthic animals such as meiofauna and bacteria and thus stimulating mineralisation. Whether this biological transport facilitates fresh organic matter assimilation by the metazoan lower part of the food web through niche establishment (i.e., ecosystem engineering or rather deprives them from food sources, is so far unclear. We investigated the effects of the ecosystem engineers Lanice conchilega (bio-irrigator and Abra alba (bioturbator compared to abiotic physical mixing events on survival and food uptake of nematodes after a simulated phytoplankton bloom. The (13C labelled diatom Skeletonema costatum was added to 4 treatments: (1 microcosms containing the bioturbator, (2 microcosms containing the bio-irrigator, (3 control microcosms and (4 microcosms with abiotic manual surface mixing. Nematode survival and subsurface peaks in nematode density profiles were most pronounced in the bio-irrigator treatment. However, nematode specific uptake (Δδ(13C of the added diatoms was highest in the physical mixing treatment, where macrobenthos was absent and the diatom (13C was homogenised. Overall, nematodes fed preferentially on bulk sedimentary organic material rather than the added diatoms. The total C budget (µg C m(-2, which included TO(13C remaining in the sediment, respiration, nematode and macrobenthic uptake, highlighted the limited assimilation by the metazoan benthos and the major role of bacterial respiration. In summary, bioturbation and especially bio-irrigation facilitated the lower trophic levels mainly over the long-term through niche establishment. Since the freshly added diatoms represented only a limited food

  11. Reactive Carbonyl Species In Vivo: Generation and Dual Biological Effects

    Directory of Open Access Journals (Sweden)

    Halyna M. Semchyshyn

    2014-01-01

    Full Text Available Reactive carbonyls are widespread species in living organisms and mainly known for their damaging effects. The most abundant reactive carbonyl species (RCS are derived from oxidation of carbohydrates, lipids, and amino acids. Chemical modification of proteins, nucleic acids, and aminophospholipids by RCS results in cytotoxicity and mutagenicity. In addition to their direct toxicity, modification of biomolecules by RCS gives rise to a multitude of adducts and cross links that are increasingly implicated in aging and pathology of a wide range of human diseases. Understanding of the relationship between metabolism of RCS and the development of pathological disorders and diseases may help to develop effective approaches to prevent a number of disorders and diseases. On the other hand, constant persistence of RCS in cells suggests that they perform some useful role in living organisms. The most beneficial effects of RCS are their establishment as regulators of cell signal transduction and gene expression. Since RCS can modulate different biological processes, new tools are required to decipher the precise mechanisms underlying dual effects of RCS.

  12. Hydrodynamic collective effects of active proteins in biological membranes

    Science.gov (United States)

    Koyano, Yuki; Kitahata, Hiroyuki; Mikhailov, Alexander S.

    2016-08-01

    Lipid bilayers forming biological membranes are known to behave as viscous two-dimensional fluids on submicrometer scales; usually they contain a large number of active protein inclusions. Recently, it was shown [A. S. Mikhailov and R. Kapral, Proc. Natl. Acad. Sci. USA 112, E3639 (2015), 10.1073/pnas.1506825112] that such active proteins should induce nonthermal fluctuating lipid flows leading to diffusion enhancement and chemotaxislike drift for passive inclusions in biomembranes. Here, a detailed analytical and numerical investigation of such effects is performed. The attention is focused on the situations when proteins are concentrated within lipid rafts. We demonstrate that passive particles tend to become attracted by active rafts and are accumulated inside them.

  13. Effect of Computer Animations Upon Student's Achievement of Biology Education

    Directory of Open Access Journals (Sweden)

    Mehmet YAKIŞAN

    2009-08-01

    Full Text Available The prime purpose of this study is to investigate the effect of computer animation supported biology education upon students’ academic achievement. The study was participated by 97 pre service teachers studying in the first year of university. The data were collected by “Cell Achievement Test” There were control and experimental groups formed and the experimental group was taught with computer animations related with diffusion, osmosis, active transport, protein synthesis, mitosis and meiosis phenomena taking place in cell while the control group was taught with traditional method based on question and answer process. The data obtained were evaluated by t- test and represented by tables and graphs. The results of the study indicated significant differences between the academic achievements of control and experimental groups. The difference is in the favor of the experimental group which revealed the fact the computer animations caused a significant increase in the academic achievements of the students.

  14. Investigation on inhibition of biological effects of endothelin

    Institute of Scientific and Technical Information of China (English)

    田青; 赵东; 张继峰; 高连如; 刘胜昔; 杨军; 苏静怡; 张肇康; 汤健; 唐朝枢

    1996-01-01

    The effects of a series of substances on the biological function of endothelin (ET) are reported. The substances used are: synthetic inhibitors of endothelium derived relaxing factors (EDRFs), inhibitor of big-endothelin converting enzyme phosphoramidon, antiserum of endothelin, antagonists of endothelin A receptor BQ123 and JKC301, and two Chinese anti-snake venom herb medicines Lobelia radians Thumb and Taris polyphylla Smith var. chinensis (Franch) Hara. The results showed that inhibiting the production of nitric oxide (NO) could stimulate ET release from vascular endothelium, elevate plasma ET and increase blood pressure. These changes could be reversed by L-arginine (L-Arg), the substrate of nitric oxide synthase (NOS). The amount of ET released by arterial endothelium could be increased or inhibited by inhibiting or stimulating the synthesis of prostacyclin (PGI2). The plasma ET level and blood pressure in both SHR and WKY rats could be decreased by giving phosphoramidon (PhR). The above results i

  15. Biological Effects on Fruit Fly by N+ ion Beam Implantation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Mutation induced by low energy ion beam implantation has beenapplied widely both in plants and microbes. However, due to the vacuum limitation, such ion implantation into animals was never studied except for silkworm. In this study, Pupae of fruit fly were irradiated with different dosage N+ ions at energy 20 KeV to study the biological effect of ion beam on animal. The results showed a saddle-like curve exists between incubate rate and dosage. Damage of pupae by ion beam implantation was observed using scanning electron microscope. Some individuals with incomplete wing were obtained after implantation but no similar character was observed in their offspring. Furthermore, about 5.47% mutants with wide variation appeared in M1 generation. Therefore, ion beam implantation could be widely used for mutation breeding.

  16. Biological effects and equivalent doses in radiotherapy: a software solution

    CERN Document Server

    Voyant, Cyril; Roustit, Rudy; Biffi, Katia; Marcovici, Celine Lantieri

    2013-01-01

    The limits of TDF (time, dose, and fractionation) and linear quadratic models have been known for a long time. Medical physicists and physicians are required to provide fast and reliable interpretations regarding the delivered doses or any future prescriptions relating to treatment changes. We therefore propose a calculation interface under the GNU license to be used for equivalent doses, biological doses, and normal tumor complication probability (Lyman model). The methodology used draws from several sources: the linear-quadratic-linear model of Astrahan, the repopulation effects of Dale, and the prediction of multi-fractionated treatments of Thames. The results are obtained from an algorithm that minimizes an ad-hoc cost function, and then compared to the equivalent dose computed using standard calculators in seven French radiotherapy centers.

  17. Effect of choline carboxylate ionic liquids on biological membranes.

    Science.gov (United States)

    Rengstl, Doris; Kraus, Birgit; Van Vorst, Matthew; Elliott, Gloria D; Kunz, Werner

    2014-11-01

    Choline carboxylates, ChCm, with m=2-10 and choline oleate are known as biocompatible substances, yet their influence on biological membranes is not well-known, and the effect on human skin has not previously been investigated. The short chain choline carboxylates ChCm with m=2, 4, 6 act as hydrotropes, solubilizing hydrophobic compounds in aqueous solution, while the longer chain choline carboxylates ChCm with m=8, 10 and oleate are able to form micelles. In the present study, the cytotoxicity of choline carboxylates was tested using HeLa and SK-MEL-28 cells. The influence of these substances on liposomes prepared from dipalmitoylphosphatidylcholine (DPPC) was also evaluated to provide insights on membrane interactions. It was observed that the choline carboxylates with a chain length of m>8 distinctly influence the bilayer, while the shorter ones had minimal interaction with the liposomes.

  18. Behavioural biology: an effective and relevant conservation tool.

    Science.gov (United States)

    Buchholz, Richard

    2007-08-01

    'Conservation behaviour' is a young discipline that investigates how proximate and ultimate aspects of the behaviour of an animal can be of value in preventing the loss of biodiversity. Rumours of its demise are unfounded. Conservation behaviour is quickly building a capacity to positively influence environmental decision making. The theoretical framework used by animal behaviourists is uniquely valuable to elucidating integrative solutions to human-wildlife conflicts, efforts to reintroduce endangered species and reducing the deleterious effects of ecotourism. Conservation behaviourists must join with other scientists under the multidisciplinary umbrella of conservation biology without giving up on their focus: the mechanisms, development, function and evolutionary history of individual differences in behaviour. Conservation behaviour is an increasingly relevant tool in the preservation of nature.

  19. [The biological effect of fireproof ceramic fibers--literature review].

    Science.gov (United States)

    Krajnow, A

    1996-01-01

    The work presents reports, selected from the world literature, on the studies of biological effect of refractory ceramic fibres, carried out on experimental animals. The discrepancy between the results of studies performed may originate from differences in the distribution of fibre sizes or the durability of fibres in the organism and their surface properties which, in turn, depend on the chemical composition of fibres. In all studies discussed, ceramic fibres generally activated macrophages and they were characterised by a moderate fibrotic activity. A statistically significant increase in the incidence of tumor (mesothelioma) observed in several very important experimental studies may suggest that some types of refractory ceramic fibres show a similar carcinogenic potential to that of natural asbestos: crocidolite or chrysotile.

  20. Effect of Antimicrobial Peptide-Amide: Indolicidin on Biological Membranes

    Directory of Open Access Journals (Sweden)

    Attila Gergely Végh

    2011-01-01

    Full Text Available Indolicidin, a cationic antimicrobial tridecapeptide amide, is rich in proline and tryptophan residues. Its biological activity is intensively studied, but the details how indolicidin interacts with membranes are not fully understood yet. We report here an in situ atomic force microscopic study describing the effect of indolicidin on an artificial supported planar bilayer membrane of dipalmitoyl phosphatidylcholine (DPPC and on purple membrane of Halobacterium salinarum. Concentration dependent interaction of the peptide and membranes was found in case of DPPC resulting the destruction of the membrane. Purple membrane was much more resistant against indolicidin, probably due to its high protein content. Indolicidin preferred the border of membrane disks, where the lipids are more accessible. These data suggest that the atomic force microscope is a powerful tool in the study of indolicidin-membrane interaction.

  1. Interaction mechanisms and biological effects of static magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Tenforde, T.S.

    1994-06-01

    Mechanisms through which static magnetic fields interact with living systems are described and illustrated by selected experimental observations. These mechanisms include electrodynamic interactions with moving, ionic charges (blood flow and nerve impulse conduction), magnetomechanical interactions (orientation and translation of molecules structures and magnetic particles), and interactions with electronic spin states in charge transfer reactions (photo-induced electron transfer in photosynthesis). A general summary is also presented of the biological effects of static magnetic fields. There is convincing experimental evidence for magnetoreception mechanisms in several classes of lower organisms, including bacteria and marine organisms. However, in more highly evolved species of animals, there is no evidence that the interactions of static magnetic fields with flux densities up to 2 Tesla (1 Tesla [T] = 10{sup 4} Gauss) produce either behavioral or physiolocical alterations. These results, based on controlled studies with laboratory animals, are consistent with the outcome of recent epidemiological surveys on human populations exposed occupationally to static magnetic fields.

  2. 21 CFR 601.26 - Reclassification procedures to determine that licensed biological products are safe, effective...

    Science.gov (United States)

    2010-04-01

    ... licensed biological products are safe, effective, and not misbranded under prescribed, recommended, or... Reclassification procedures to determine that licensed biological products are safe, effective, and not misbranded... for the reclassification of all biological products that have been classified into Category IIIA....

  3. Biological effects due to weak magnetic fields on plants

    Science.gov (United States)

    Belyavskaya, N.

    In the evolution process, living organisms have experienced the action of the Earth's magnetic field (MF) that is a natural component of our environment. It is known that a galactic MF induction does not exceed 0.1 nT, since investigations of weak magnetic field (WMF) effects on biological systems have attracted attention of biologists due to planning long-term space flights to other planets where the magnetizing force is near 10-5 Oe. However, the role of WMF and its influence on organisms' functioning are still insufficiently investigated. A large number of experiments with seedlings of different plant species placed in WMF has found that the growth of their primary roots is inhibited during the early terms of germination in comparison with control. The proliferation activity and cell reproduction are reduced in meristem of plant roots under WMF application. The prolongation of total cell reproductive cycle is registered due to the expansion of G phase in1 different plant species as well as of G phase in flax and lentil roots along with2 relative stability of time parameters of other phases of cell cycle. In plant cells exposed to WMF, the decrease in functional activity of genome at early prereplicate period is shown. WMF causes the intensification in the processes of proteins' synthesis and break-up in plant roots. Qualitative and quantitative changes in protein spectrum in growing and differentiated cells of plant roots exposed to WMF are revealed. At ultrastructural level, there are observed such ultrastructural peculiarities as changes in distribution of condensed chromatin and nucleolus compactization in nuclei, noticeable accumulation of lipid bodies, development of a lytic compartment (vacuoles, cytosegresomes and paramural bodies), and reduction of phytoferritin in plastids in meristem cells of pea roots exposed to WMF. Mitochondria are the most sensitive organelle to WMF application: their size and relative volume in cells increase, matrix is electron

  4. Effect of a biological activated carbon filter on particle counts

    Institute of Scientific and Technical Information of China (English)

    Su-hua WU; Bing-zhi DONG; Tie-jun QIAO; Jin-song ZHANG

    2008-01-01

    Due to the importance of biological safety in drinking water quality and the disadvantages which exist in traditional methods of detecting typical microorganisms such as Cryptosporidium and Giardia,it is necessary to develop an alternative.Particle counts is a qualitative measurement of the amount of dissolved solids in water.The removal rate of particle counts was previously used as an indicator of the effectiveness of a biological activated carbon(BAC)filter in removing Cryptosporidium and Giardia.The particle counts in a BAC filter effluent over one operational period and the effects of BAC filter construction and operational parameters were investigated with a 10 m3/h pilot plant.The results indicated that the maximum particle count in backwash remnant water was as high as 1296 count/ml and it needed about 1.5 h to reduce from the maximum to less than 50 count/ml.During the standard filtration period,particle counts stay constant at less than 50 count/ml for 5 d except when influ-enced by sand filter backwash remnant water.The removal rates of particle counts in the BAC filter are related to characteristics of the carbon.For example,a columned carbon and a sand bed removed 33.3% and 8.5% of particles,respectively,while the particle counts in effluent from a cracked BAC filter was higher than that of the influent.There is no significant difference among particle removal rates with different filtration rates.High post-ozone dosage(>2 mg/L)plays an important role in particle count removal;when the dosage was 3 mg/L,the removal rates by carbon layers and sand beds decreased by 17.5% and increased by 9.5%,respectively,compared with a 2 mg/L dosage.

  5. The effect of air supply on nitrogen removal using a biological filter ...

    African Journals Online (AJOL)

    The effect of air supply on nitrogen removal using a biological filter proposed for ventilated pit latrines. ... In this research the nitrogen was removed in a biological filter using a combination of nitrification and denitrification ... Article Metrics.

  6. Mutagenic Effects of Iron Oxide Nanoparticles on Biological Cells.

    Science.gov (United States)

    Dissanayake, Niluka M; Current, Kelley M; Obare, Sherine O

    2015-09-30

    In recent years, there has been an increased interest in the design and use of iron oxide materials with nanoscale dimensions for magnetic, catalytic, biomedical, and electronic applications. The increased manufacture and use of iron oxide nanoparticles (IONPs) in consumer products as well as industrial processes is expected to lead to the unintentional release of IONPs into the environment. The impact of IONPs on the environment and on biological species is not well understood but remains a concern due to the increased chemical reactivity of nanoparticles relative to their bulk counterparts. This review article describes the impact of IONPs on cellular genetic components. The mutagenic impact of IONPs may damage an organism's ability to develop or reproduce. To date, there has been experimental evidence of IONPs having mutagenic interactions on human cell lines including lymphoblastoids, fibroblasts, microvascular endothelial cells, bone marrow cells, lung epithelial cells, alveolar type II like epithelial cells, bronchial fibroblasts, skin epithelial cells, hepatocytes, cerebral endothelial cells, fibrosarcoma cells, breast carcinoma cells, lung carcinoma cells, and cervix carcinoma cells. Other cell lines including the Chinese hamster ovary cells, mouse fibroblast cells, murine fibroblast cells, Mytilus galloprovincialis sperm cells, mice lung cells, murine alveolar macrophages, mice hepatic and renal tissue cells, and vero cells have also shown mutagenic effects upon exposure to IONPs. We further show the influence of IONPs on microorganisms in the presence and absence of dissolved organic carbon. The results shed light on the OPEN ACCESS Int. J. Mol. Sci. 2015, 16 23483 transformations IONPs undergo in the environment and the nature of the potential mutagenic impact on biological cells.

  7. Improved intercostal HIFU ablation using a phased array transducer based on Fermat's spiral and Voronoi tessellation: A numerical evaluation.

    Science.gov (United States)

    Ramaekers, Pascal; Ries, Mario; Moonen, Chrit T W; de Greef, Martijn

    2017-03-01

    A major complication for abdominal High Intensity Focused Ultrasound (HIFU) applications is the obstruction of the acoustic beam path by the thoracic cage, which absorbs and reflects the ultrasonic energy leading to undesired overheating of healthy tissues in the pre-focal area. Prior work has investigated the determination of optimized transducer apodization laws, which allow for a reduced rib exposure whilst (partially) restoring focal point intensity through power compensation. Although such methods provide an excellent means of reducing rib exposure, they generally increase the local energy density in the pre-focal area, which similarly can lead to undesired overheating. Therefore, this numerical study aimed at evaluating whether a novel transducer design could provide improvement for intercostal HIFU applications, in particular with respect to the pre-focal area. A combination of acoustic and thermal simulations was used to evaluate 2 mono-element transducers, 2 clinical phased array transducers, and 4 novel transducers based on Fermat's Spiral (FS), two of which were Voronoi-tessellated (VTFS). Binary apodizations were determined for the phased array transducers using a collision detection algorithm. A tissue geometry was modeled to represent an intercostal HIFU sonication in the liver at 30 and 50 mm behind the ribs, including subsequent layers of gel pad, skin, subcutaneous fat, muscle, and liver tissue. Acoustic simulations were then conducted using propagation of the angular spectrum of plane waves (ASPW). The results of these simulations were used to evaluate pre-focal intensity levels. Subsequently, a finite difference scheme based on the Pennes bioheat equation was used for thermal simulations. The results of these simulations were used to calculate both the energy density in the pre-focal skin, fat, and muscle layers, as well as the energy exposure of the ribs. The acoustic simulations showed that for a sonication in a single point without

  8. The effect of green tea on radiation-induced late biological effect in mice

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Ho; Kim, Se Ra; Lee, Hae June; Jo, Sung Kee [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2004-07-01

    This study was performed to determine the effect of Green tea on the late biological effect of mice irradiated with 3 Gy of gamma-radiation. There were various findings including hematopoietic and lymphoid tumor, lung cancer, ovarian cancer and cancer of other lesions. Further studies are needed to characterize better the protective nature of active compounds.

  9. A drug-perfluorocarbon nanoemulsion with an ultrathin silica coating for the synergistic effect of chemotherapy and ablation by high-intensity focused ultrasound.

    Science.gov (United States)

    Ma, Ming; Xu, Huixiong; Chen, Hangrong; Jia, Xiaoqing; Zhang, Kun; Wang, Qi; Zheng, Shuguang; Wu, Rong; Yao, Minghua; Cai, Xiaojun; Li, Faqi; Shi, Jianlin

    2014-11-19

    The synergistic effect of chemotherapy and ablation using high-intensity focused ultrasound (HIFU) is realized with a newly developed drug-delivery system. The system comprises an ultrathin silica shell surrounding a poly(lactic-co-glycolic acid) nanoemulsion core containing the drug (CPT) and a perfluorocarbon (PFOB). This nanosystem presents many advantages in drug delivery, such as excellent structural stability, high drug-loading capacity, and rapid HIFU-mediated drug release.

  10. New Scientific Pearl about Biologic Effect of Ionizing Radiation

    Directory of Open Access Journals (Sweden)

    S. A. Alamdaran

    2008-01-01

    Full Text Available Soon after the discovery of X-ray by Rontgen in 1895, it became evident that radiation can cause some somatic damage to tissues. The hazards of X-ray exposure were clearly known when many large hospitals had radiology departments. The greatest increased in knowledge about X-ray risks had accrued from the dropping of the two atomic bombs in Japan in 1945 and some other atomic accident. For example, among the Japanese bomb survivors from Hiroshima and Nagasaki, there have been about 400 extra cancer deaths. These were the origin of radiology personnel and people fear from radiation exposure and resistant in against simple X-ray exam (radiophobia. However, new scientific data on the effects radiation on survivors, especially about biologic effect of ionizing rays, background radiation exposure, amount of endogenous radiation, hormosis phenomenon and comparison radiation risk with other risk over lifetime are still being continuously revised and risk estimates updated. Fundamentally, this risk is much"nlower than whatever already estimated and it is insignificant in diagnostic domain. Better perception of physician from these instances help to prevent of false radiophobia and to make proper use of diagnostic and therapeutic advantages of ionizing beam.

  11. Effect of Sedimentation on Treated Greywater Through Rotating Biological Contactor

    Directory of Open Access Journals (Sweden)

    Ashfaque Ahmed Pathan

    2016-06-01

    Full Text Available The aim of this paper was to study the effect of sedimentation on effluent of a pilot scale Rotating Biological Contactor (RBC. The treated greywater was given three hours sedimentation period and samples were analyzed to observe the effect of sedimentations under variousflow rates. Greywater was separated from the black water and collected in the collection tank and then it was pumped to an overhead tank. This tank supplied a regulated continuous flow of greywater into the RBC chamber at the required flow rate ranging between 0.28 to 1.89 l/min. A pilot scale RBC simulator was developed and placed outside a hall of residence at National Center of Excellence in Analytical Chemistry, Sindh University, Jamshoro. The simulator was operated at the rotational speed of discs of 1.7 rpm. The disks were uneven and textured so as to encourage growth of bacteria on them. These discs were immersed about 40 percent in the greywater.The simulator produced effluent of significant quality and was found efficient in removal of BOD5, COD and TSS as 85%, 68% and 95% respectively.

  12. [Effects of decitabine on biological behavior of U266 cells].

    Science.gov (United States)

    Wang, Mei-Fang; Yang, Lin-Hua; Dong, Chun-Xia; Zhang, Rui-Juan; Zhang, Jian-Hua; Guo, Zhi-Ping; Chen, Jian-Fang; Zhagn, Li; Feng, Da-Wei

    2011-08-01

    This study was aimed to explore the effects of decitabine on the biological behaviour of U266 cells in vitro so as to provide a new thinking and experiment basis, as well as new evidences for the pathogenesis of multiple myeloma. MTT and colony formation assays were used to evaluate the impact of decitabine on the ability of proliferation of U266 cells; flow cytometry was used to analyze the cell distribution in cell cycle; transwell chamber and matrigel assays were used to observe the ability of migration and invasion. The results indicated that decitabine could significantly suppress the proliferation of U266 cells in time-and dose-dependent manners. The flow cytometric analysis demonstrated that the cells in G(0)-G(1) phase significantly increased while the cells in S and G(2)/M phase decreased. The migration and matrigel invading tests showed that the number of cells moving into under chamber of transwell decreased after U266 cells treated with decitabine. It is concluded that decitabine may act as an effective drug for MM by inhibiting the proliferation, migration and invasion ability, and the specific mechanism needs to be deeply explored.

  13. Enhanced Biological Phosphorus Removal: Metabolic Insights and Salinity Effects

    NARCIS (Netherlands)

    Welles, L.

    2015-01-01

    Enhanced biological phosphorus removal (EBPR) is a biological process for efficient phosphate removal from wastewaters through intracellular storage of polyphosphate by polyphosphate-accumulating organisms (PAO) and subsequent removal of PAO from the system through wastage of sludge. In comparison t

  14. The biological effects of ionising radiation on Crustaceans: A review

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, Neil; Lerebours, Adélaïde [Institute of Marine Sciences, School of Biological Sciences, University of Portsmouth, Ferry Road, Portsmouth, Hampshire PO4 9LY (United Kingdom); Smith, Jim T. [School of Earth & Environmental Sciences, University of Portsmouth, Burnaby Building, Burnaby Road, Portsmouth, Hampshire PO1 3QL (United Kingdom); Ford, Alex T., E-mail: alex.ford@port.ac.uk [Institute of Marine Sciences, School of Biological Sciences, University of Portsmouth, Ferry Road, Portsmouth, Hampshire PO4 9LY (United Kingdom)

    2015-10-15

    Highlights: • We comprehensively review the effects of ionising radiation in crustaceans. • Current environmental radioprotection levels found to be inadequate in some cases. • Mutation is shown to be a sensitive endpoint of radiation exposure. • Lowest observed effect dose rate varies by orders of magnitude. - Abstract: Historic approaches to radiation protection are founded on the conjecture that measures to safeguard humans are adequate to protect non-human organisms. This view is disparate with other toxicants wherein well-developed frameworks exist to minimise exposure of biota. Significant data gaps for many organisms, coupled with high profile nuclear incidents such as Chernobyl and Fukushima, have prompted the re-evaluation of our approach toward environmental radioprotection. Elucidating the impacts of radiation on biota has been identified as priority area for future research within both scientific and regulatory communities. The crustaceans are ubiquitous in aquatic ecosystems, comprising greater than 66,000 species of ecological and commercial importance. This paper aims to assess the available literature of radiation-induced effects within this subphylum and identify knowledge gaps. A literature search was conducted pertaining to radiation effects on four endpoints as stipulated by a number of regulatory bodies: mortality, morbidity, reproduction and mutation. A major finding of this review was the paucity of data regarding the effects of environmentally relevant radiation doses on crustacean biology. Extremely few studies utilising chronic exposure durations or wild populations were found across all four endpoints. The dose levels at which effects occur was found to vary by orders of magnitude thus presenting difficulties in developing phyla-specific benchmark values and reference levels for radioprotection. Based on the limited data, mutation was found to be the most sensitive endpoint of radiation exposure, with mortality the least sensitive

  15. 11C choline PET guided salvage radiotherapy with volumetric modulation arc therapy and hypofractionation for recurrent prostate cancer after HIFU failure: preliminary results of tolerability and acute toxicity.

    Science.gov (United States)

    Alongi, Filippo; Liardo, Rocco L E; Iftode, Cristina; Lopci, Egesta; Villa, Elisa; Comito, Tiziana; Tozzi, Angelo; Navarria, Pierina; Ascolese, Anna M; Mancosu, Pietro; Tomatis, Stefano; Bellorofonte, Carlo; Arturo, Chiti; Scorsetti, Marta

    2014-10-01

    The purpose of this work was to evaluate tolerance, feasibility and acute toxicity in patients undergoing salvage radiotherapy after high-intensity focused ultrasound (HIFU) failure. From 2005 to 2011 a total of 15 patients were treated with HIFU as primary radical treatment. Between July 2011 and February 2013, all 15 patients presented biochemical relapse after HIFU and 11C choline PET documenting intrapostatic-only failure. Salvage EBRT was performed with moderate hypofractionation schedule in 28 fractions with volumetric modulation arc therapy (VMAT). Genito-urinary (GU) and rectal and bowel toxicity were scored by common terminology criteria for adverse events version 4 (CTCAE V.4) scale. Biochemical response was assessed by ASTRO Phoenix criteria. Median age of patients was 67 years (range: 53-85). The median Gleason score was 7 (range: 6-9). The median prostate specific antigen (PSA) at the time of biochemical relapse after HIFU was 5.2 ng/mL (range: 2-64.2). Seven of the 15 patients received androgen deprivation therapy (ADT) started after HIFU failure, interrupted before 11C choline PET and radiotherapy. Median prescribed dose was 71.4 Gy (range: 71.4-74.2 Gy) in 28 fractions. No radiation related major upper gastrointestinal (GI), rectal and GU toxicity were experienced. GU, acute grade 1 and grade 2 toxicities were recorded in 7/15 and 4/15 respectively; bowel acute grade 1 and grade 2 toxicities in 4/15 and 1/15; rectal acute grade 1 and grade 2 toxicities in 3/15 and 2/15 respectively. No grade 3 or greater acute or late toxicities occurred. Biochemical control was assessed in 12/15 (80%) patients. With a median follow up of 12 months, three out of 15 patients, with biochemical relapse, showed lymph-nodal recurrence. Our early clinical results and biochemical data confirm the feasibility and show a good tolerance of the 11C choline PET guided salvage radiation therapy after HIFU failure. The findings of low acute toxicity is encouraging, but longer

  16. Treatment of hepatic tumors by thermal versus mechanical effects of pulsed high intensity focused ultrasound in vivo

    Science.gov (United States)

    Peng, Song; Zhou, Ping; He, Wei; Liao, Manqiong; Chen, Lili; Ma, C.-M.

    2016-09-01

    The purpose of this study is to comparatively assess the thermal versus mechanical effects of pulsed high intensity focused ultrasound (HIFU) treatment on hepatic tumors in vivo. Forty-five rabbits with hepatic VX2 tumors were randomly separated into three groups (15 animals per group) before HIFU ablation. The total HIFU energy (in situ) of 1250 J was used for each tumor for three groups. In groups I and II, animals were treated with 1 MHz pulsed ultrasound at 1 Hz pulsed repetition frequency (PRF), 0.5 duty cycle (0.5 s on and 0.5 s off) and10 s duration for one spot sonication. For group II, in addition to HIFU treatment, microbubbles (SonoVue, Bracco, Milan, Italy) were injected via vein before sonication acting as a synergist. In group III, animals were treated with 1 MHz pulsed ultrasound at 10 Hz PRF, 0.1 duty cycle (0.1 s on and 0.9 s off) and 10 s duration for one sonication. The total treatment spots were calculated according to the tumor volume. Tumors were examined with contrast-enhanced computed tomography (CECT) immediately prior to and post HIFU treatment. Histopathologic assessment was performed 3 h after treatment. Our study showed that all animals tolerated the HIFU treatment well. Our data showed that mechanical HIFU could lead to controlled injury in rabbit hepatic tumors with different histological changes in comparison to thermal HIFU with or without microbubbles.

  17. The effect of network biology on drug toxicology

    DEFF Research Database (Denmark)

    Gautier, Laurent; Taboureau, Olivier; Audouze, Karine Marie Laure

    2013-01-01

    it with bioinformatics. With this approach, the assessment of chemical safety can be done across multiple scales of complexity from molecular to cellular and system levels in human health. Network biology can be used at several levels of complexity. Areas covered: This review describes the strengths and limitations......Introduction: The high failure rate of drug candidates due to toxicity, during clinical trials, is a critical issue in drug discovery. Network biology has become a promising approach, in this regard, using the increasingly large amount of biological and chemical data available and combining...... of network biology. The authors specifically assess this approach across different biological scales when it is applied to toxicity. Expert opinion: There has been much progress made with the amount of data that is generated by various omics technologies. With this large amount of useful data, network...

  18. Examining the Effect of Multiple Writing Tasks on Year 10 Biology Students' Understandings of Cell and Molecular Biology Concepts

    Science.gov (United States)

    Hand, Brian; Hohenshell, Liesl; Prain, Vaughan

    2007-01-01

    This paper reports on a study that examined the cumulative effects on students' learning of science, and perceptions of the role of writing in learning, when the students engaged in multiple writing tasks with planning strategy support. The study was conducted with Year 10 biology students who completed two consecutive units on Cells and Molecular…

  19. Nanogold – Biological effects and occupational exposure levels

    Directory of Open Access Journals (Sweden)

    Anna Maria Świdwińska-Gajewska

    2017-08-01

    Full Text Available Nanogold has different properties and biological activity compared to metallic gold. It can be applied in many fields, such as medicine, laboratory diagnostics and electronics. Studies on laboratory animals show that nanogold can be absorbed by inhalation and ingestion. It can penetrate deep into the epidermis and dermis, but there is no evidence that it is absorbed through the skin. Gold nanoobjects accumulate mainly in the liver and spleen, but they can also reach other internal organs. Nanogold can cross the blood–brain and blood–placenta barriers. Toxicokinetics of nanogold depends on the particle size, shape and surface charge. In animals exposure to gold nanoparticles via inhalation induces slight changes in the lungs. Exposure to nanogold by the oral route does not cause adverse health effects in rodents. In animals after injection of gold nanoobjects changes in the liver and lungs were observed. Nanogold induced genotoxic effects in cells, but not in animals. No adverse effects on the fetus or reproduction were found. There are no carcinogenicity studies on gold nanoparticles. The mechanism of toxicity may be related to the interaction of gold nanoobjects with proteins and DNA, and it leads to the induction of oxidative stress and genetic material damage. The impact of nanostructures on human health has not yet been fully understood. The person, who works with nanomaterials should exercise extreme caution and apply existing recommendations on the evaluation of nanoobjects exposure. The risk assessment should be the basis for taking appropriate measures to limit potential exposure to nanometals, including nanogold. Med Pr 2017;68(4:545–556

  20. Occurrence and Potential Biological Effects of Amphetamine on Stream Communities.

    Science.gov (United States)

    Lee, Sylvia S; Paspalof, Alexis M; Snow, Daniel D; Richmond, Erinn K; Rosi-Marshall, Emma J; Kelly, John J

    2016-09-06

    The presence of pharmaceuticals, including illicit drugs in aquatic systems, is a topic of environmental significance because of their global occurrence and potential effects on aquatic ecosystems and human health, but few studies have examined the ecological effects of illicit drugs. We conducted a survey of several drug residues, including the potentially illicit drug amphetamine, at 6 stream sites along an urban to rural gradient in Baltimore, Maryland, U.S.A. We detected numerous drugs, including amphetamine (3 to 630 ng L(-1)), in all stream sites. We examined the fate and ecological effects of amphetamine on biofilm, seston, and aquatic insect communities in artificial streams exposed to an environmentally relevant concentration (1 μg L(-1)) of amphetamine. The amphetamine parent compound decreased in the artificial streams from less than 1 μg L(-1) on day 1 to 0.11 μg L(-1) on day 22. In artificial streams treated with amphetamine, there was up to 45% lower biofilm chlorophyll a per ash-free dry mass, 85% lower biofilm gross primary production, 24% greater seston ash-free dry mass, and 30% lower seston community respiration compared to control streams. Exposing streams to amphetamine also changed the composition of bacterial and diatom communities in biofilms at day 21 and increased cumulative dipteran emergence by 65% and 89% during the first and third weeks of the experiment, respectively. This study demonstrates that amphetamine and other biologically active drugs are present in urban streams and have the potential to affect both structure and function of stream communities.

  1. Determining environmental causes of biological effects: the need for a mechanistic physiological dimension in conservation biology

    OpenAIRE

    Seebacher, Frank; Craig E. Franklin

    2012-01-01

    The emerging field of Conservation Physiology links environmental change and ecological success by the application of physiological theory, approaches and tools to elucidate and address conservation problems. Human activity has changed the natural environment to a point where the viability of many ecosystems is now under threat. There are already many descriptions of how changes in biological patterns are correlated with environmental changes. The next important step is to determine the causa...

  2. Relative Biological Effectiveness and Peripheral Damage of Antiproton Annihilation

    CERN Multimedia

    Kavanagh, J N; Kaiser, F; Tegami, S; Schettino, G; Kovacevic, S; Hajdukovic, D; Currell, F J; Toelli, H T; Doser, M; Holzscheiter, M; Herrmann, R; Timson, D J; Alsner, J; Landua, R; Knudsen, H; Comor, J; Moller, S P; Beyer, G

    2002-01-01

    The use of ions to deliver radiation to a body for therapeutic purposes has the potential to be significant improvement over the use of low linear energy transfer (LET) radiation because of the improved energy deposition profile and the enhanced biological effects of ions relative to photons. Proton therapy centers exist and are being used to treat patients. In addition, the initial use of heavy ions such as carbon is promising to the point that new treatment facilities are planned. Just as with protons or heavy ions, antiprotons can be used to deliver radiation to the body in a controlled way; however antiprotons will exhibit additional energy deposition due to annihilation of the antiprotons within the body. The slowing down of antiprotons in matter is similar to that of protons except at the very end of the range beyond the Bragg peak. Gray and Kalogeropoulos estimated the additional energy deposited by heavy nuclear fragments within a few millimeters of the annihilation vertex to be approximately 30 MeV (...

  3. Biological effectiveness of neutron irradiation on animals and man

    Energy Technology Data Exchange (ETDEWEB)

    Straume, T.

    1982-11-01

    Neutron experiments on a highly radiosensitive in vivo system - oocytes in mice - provide new insight into the nature of the radiosensitive targets of these important cells. With the radiobiological literature as background, neutron data from animals and humans are integrated, and the controversial question of radiation protection standards for neutrons is addressed. Oocyte killing in juvenile mice by 0.43-MeV, /sup 252/Cf-fission, and 15 MeV neutrons, compared with that by /sup 60/Co gamma rays, yields unusually low neutron RBEs (relative biological effectiveness). At 0.1 rad of 0.43-MeV neutrons the RBE is only 1.8, contrasting greatly with values of 100 or more reported at low-doses for other endpoints. In mice just prior to birth, however, when oocytes are less radiosensitive, the neutron RBE is much higher, similar to values for most other mammalian endpoints. This dramatic change in neutron RBE with mouse age (occurring within 2 to 3 days) can be explained as the result of a shift from a less radiosensitive target (presumably nuclear DNA) to a much more radiosensitive one (probably the oocyte plasma membrane). Using various approaches, a value for the neutron Quality Factor (Q, a radiation protection standard) is estimated as 17 (+-100%), much lower than 100 which has been suggested. With the large uncertainty, 17 is not markedly different from the value of 10 presently in general use.

  4. Effects of Simulated Rare Earth Recycling Wastewaters on Biological Nitrification.

    Science.gov (United States)

    Fujita, Yoshiko; Barnes, Joni; Eslamimanesh, Ali; Lencka, Malgorzata M; Anderko, Andrzej; Riman, Richard E; Navrotsky, Alexandra

    2015-08-18

    Increasing rare earth element (REE) supplies by recycling and expanded ore processing will result in generation of new wastewaters. In some cases, disposal to a sewage treatment plant may be favored, but plant performance must be maintained. To assess the potential effects of such wastewaters on biological treatment, model nitrifying organisms Nitrosomonas europaea and Nitrobacter winogradskyi were exposed to simulated wastewaters containing varying levels of yttrium or europium (10, 50, and 100 ppm), and the extractant tributyl phosphate (TBP, at 0.1 g/L). Y and Eu additions at 50 and 100 ppm inhibited N. europaea, even when virtually all of the REE was insoluble. Provision of TBP with Eu increased N. europaea inhibition, although TBP alone did not substantially alter activity. For N. winogradskyi cultures, Eu or Y additions at all tested levels induced significant inhibition, and nitrification shut down completely with TBP addition. REE solubility was calculated using the previously developed MSE (Mixed-Solvent Electrolyte) thermodynamic model. The model calculations reveal a strong pH dependence of solubility, typically controlled by the precipitation of REE hydroxides but also likely affected by the formation of unknown phosphate phases, which determined aqueous concentrations experienced by the microorganisms.

  5. Stochastic Effects in Computational Biology of Space Radiation Cancer Risk

    Science.gov (United States)

    Cucinotta, Francis A.; Pluth, Janis; Harper, Jane; O'Neill, Peter

    2007-01-01

    Estimating risk from space radiation poses important questions on the radiobiology of protons and heavy ions. We are considering systems biology models to study radiation induced repair foci (RIRF) at low doses, in which less than one-track on average transverses the cell, and the subsequent DNA damage processing and signal transduction events. Computational approaches for describing protein regulatory networks coupled to DNA and oxidative damage sites include systems of differential equations, stochastic equations, and Monte-Carlo simulations. We review recent developments in the mathematical description of protein regulatory networks and possible approaches to radiation effects simulation. These include robustness, which states that regulatory networks maintain their functions against external and internal perturbations due to compensating properties of redundancy and molecular feedback controls, and modularity, which leads to general theorems for considering molecules that interact through a regulatory mechanism without exchange of matter leading to a block diagonal reduction of the connecting pathways. Identifying rate-limiting steps, robustness, and modularity in pathways perturbed by radiation damage are shown to be valid techniques for reducing large molecular systems to realistic computer simulations. Other techniques studied are the use of steady-state analysis, and the introduction of composite molecules or rate-constants to represent small collections of reactants. Applications of these techniques to describe spatial and temporal distributions of RIRF and cell populations following low dose irradiation are described.

  6. Chemical and biological oxidative effects of carbon black nanoparticles.

    Science.gov (United States)

    Koike, Eiko; Kobayashi, Takahiro

    2006-11-01

    Several studies show that ultrafine particles have a larger surface area than coarse particles, thus causing a greater inflammatory response. In this study, we investigated chemical and biological oxidative effects of nanoparticles in vitro. Carbon black (CB) nanoparticles with mean aerodynamic diameters of 14, 56, and 95nm were examined. The innate oxidative capacity of the CB nanoparticles was measured by consumption of dithiothreitol (DTT) in cell-free system. The expression of heme oxygenase-1 (HO-1) in rat alveolar type II epithelial cell line (SV40T2) and alveolar macrophages (AM) exposed to CB nanoparticles was measured by ELISA. DTT consumption of 14nm CB was higher than that of other CB nanoparticles having the same particle weight. However, DTT consumption was directly proportional to the particle surface area. HO-1 protein in SV40T2 cells was significantly increased by the 14nm and 56nm CB, however, 95nm CB did not affect. HO-1 protein in AM was significantly increased by the 14, 56, and 95nm CB. The increase in HO-1 expression was diminished by N-acetyl-l-cysteine (NAC) treatment of each CB nanoparticles before exposure although the difference between the effects of NAC-treated and untreated 14nm CB did not achieve significant. In conclusion, CB nanoparticles have innate oxidative capacity that may be dependent on the surface area. CB nanoparticles can induce oxidative stress in alveolar epithelial cells and AM that is more prominent with smaller particles. The oxidative stress may, at least partially, be mediated by surface function of particles.

  7. Tea polyphenols, their biological effects and potential molecular targets.

    Science.gov (United States)

    Chen, D; Milacic, V; Chen, M S; Wan, S B; Lam, W H; Huo, C; Landis-Piwowar, K R; Cui, Q C; Wali, A; Chan, T H; Dou, Q P

    2008-04-01

    Tea is the most popular beverage in the world, second only to water. Tea contains an infusion of the leaves from the Camellia sinensis plant rich in polyphenolic compounds known as catechins, the most abundant of which is (-)-EGCG. Although tea has been consumed for centuries, it has only recently been studied extensively as a health-promoting beverage that may act to prevent a number of chronic diseases and cancers. The results of several investigations indicate that green tea consumption may be of modest benefit in reducing the plasma concentration of cholesterol and preventing atherosclerosis. Additionally, the cancer-preventive effects of green tea are widely supported by results from epidemiological, cell culture, animal and clinical studies. In vitro cell culture studies show that tea polyphenols potently induce apoptotic cell death and cell cycle arrest in tumor cells but not in their normal cell counterparts. Green tea polyphenols were shown to affect several biological pathways, including growth factor-mediated pathway, the mitogen-activated protein (MAP) kinase-dependent pathway, and ubiquitin/proteasome degradation pathways. Various animal studies have revealed that treatment with green tea inhibits tumor incidence and multiplicity in different organ sites such as skin, lung, liver, stomach, mammary gland and colon. Recently, phase I and II clinical trials have been conducted to explore the anticancer effects of green tea in humans. A major challenge of cancer prevention is to integrate new molecular findings into clinical practice. Therefore, identification of more molecular targets and biomarkers for tea polyphenols is essential for improving the design of green tea trials and will greatly assist in a better understanding of the mechanisms underlying its anti-cancer activity.

  8. Effectiveness of a biological control agent Palexorista gilvoides in ...

    African Journals Online (AJOL)

    ACSS

    Uganda Journal of Agricultural Sciences by National Agricultural Research Organisation is licensed under a ... gilvoides as a potential biological control agent for G. podocarpi. Field and .... are related to stress factors and are considered ...

  9. Sex matters: The effects of biological sex on adipose tissue biology and energy metabolism

    Directory of Open Access Journals (Sweden)

    Teresa G. Valencak

    2017-08-01

    Full Text Available Adipose tissue is a complex and multi-faceted organ. It responds dynamically to internal and external stimuli, depending on the developmental stage and activity of the organism. The most common functional subunits of adipose tissue, white and brown adipocytes, regulate and respond to endocrine processes, which then determine metabolic rate as well as adipose tissue functions. While the molecular aspects of white and brown adipose biology have become clearer in the recent past, much less is known about sex-specific differences in regulation and deposition of adipose tissue, and the specific role of the so-called pink adipocytes during lactation in females. This review summarises the current understanding of adipose tissue dynamics with a focus on sex-specific differences in adipose tissue energy metabolism and endocrine functions, focussing on mammalian model organisms as well as human-derived data. In females, pink adipocytes trans-differentiate during pregnancy from subcutaneous white adipocytes and are responsible for milk-secretion in mammary glands. Overlooking biological sex variation may ultimately hamper clinical treatments of many aspects of metabolic disorders.

  10. The Effects of Ultrasound on Biological Systems: Site

    Science.gov (United States)

    El-Karmi, Anan M.

    vs. 18 minutes). This demonstrates that the biological effects of ultrasound are influenced by Ca^ {2+}. The larger increases in G _{rm t} and the time constants confirm other studies addressing the role of Ca ^{2+} in potentiating lipid peroxidation by free radicals, and the role of calcium ions in the formation of tight junctions.

  11. Penetration and propagation into biological matter and biological effects of high-power ultra-wideband pulses: a review.

    Science.gov (United States)

    Schunck, Thérèse; Bieth, François; Pinguet, Sylvain; Delmote, Philippe

    2016-01-01

    Systems emitting ultra-wideband high power microwave (HP/UWB) pulses are developed for military and civilian applications. HP/UWB pulses typically have durations on the order of nanoseconds, rise times of picoseconds and amplitudes around 100 kV m(-1). This article reviews current research on biological effects from HP/UWB exposure. The different references were classified according to endpoints (cardiovascular system, central nervous system, behavior, genotoxicity, teratology …). The article also reviews the aspects of mechanisms of interactions and tissue damage as well as the numerical work that has been done for studying HP/UWB pulse propagation and pulse energy deposition inside biological tissues. The mechanisms proposed are the molecular conformation change, the modification of chemical reaction rates, membrane excitation and breakdown and direct electrical forces on cells or cell constituents, and the energy deposition. As regards the penetration of biological matter and the deposited energy, mainly computations were published. They have shown that the EM field inside the biological matter is strongly modified compared to the incident EM field and that the energy absorption for HP/UWB pulses occurs in the same way as for continuous waves. However, the energy carried by a HP/UWB pulse is very low and the deposited energy is low. The number of published studies dealing with the biological effects is small and only a few pointed out slight effects. It should be further noted that the animal populations used in the studies were not always large, the statistical analyses not always relevant and the teams involved in this research rather limited in number.

  12. Fast lesion mapping during HIFU treatment using harmonic motion imaging guided focused ultrasound (HMIgFUS) in vitro and in vivo

    Science.gov (United States)

    Han, Yang; Wang, Shutao; Payen, Thomas; Konofagou, Elisa

    2017-04-01

    The successful clinical application of high intensity focused ultrasound (HIFU) ablation depends on reliable monitoring of the lesion formation. Harmonic motion imaging guided focused ultrasound (HMIgFUS) is an ultrasound-based elasticity imaging technique, which monitors HIFU ablation based on the stiffness change of the tissue instead of the echo intensity change in conventional B-mode monitoring, rendering it potentially more sensitive to lesion development. Our group has shown that predicting the lesion location based on the radiation force-excited region is feasible during HMIgFUS. In this study, the feasibility of a fast lesion mapping method is explored to directly monitor the lesion map during HIFU. The harmonic motion imaging (HMI) lesion map was generated by subtracting the reference HMI image from the present HMI peak-to-peak displacement map, as streamed on the computer display. The dimensions of the HMIgFUS lesions were compared against gross pathology. Excellent agreement was found between the lesion depth (r 2  =  0.81, slope  =  0.90), width (r 2  =  0.85, slope  =  1.12) and area (r 2  =  0.58, slope  =  0.75). In vivo feasibility was assessed in a mouse with a pancreatic tumor. These findings demonstrate that HMIgFUS can successfully map thermal lesions and monitor lesion development in real time in vitro and in vivo. The HMIgFUS technique may therefore constitute a novel clinical tool for HIFU treatment monitoring.

  13. Countermeasures for Space Radiation Induced Malignancies and Acute Biological Effects

    Science.gov (United States)

    Kennedy, Ann

    The hypothesis being evaluated in this research program is that control of radiation induced oxidative stress will reduce the risk of radiation induced adverse biological effects occurring as a result of exposure to the types of radiation encountered during space travel. As part of this grant work, we have evaluated the protective effects of several antioxidants and dietary supplements and observed that a mixture of antioxidants (AOX), containing L-selenomethionine, N-acetyl cysteine (NAC), ascorbic acid, vitamin E succinate, and alpha-lipoic acid, is highly effective at reducing space radiation induced oxidative stress in both in vivo and in vitro systems, space radiation induced cytotoxicity and malignant transformation in vitro [1-7]. In studies designed to determine whether the AOX formulation could affect radiation induced mortality [8], it was observed that the AOX dietary supplement increased the 30-day survival of ICR male mice following exposure to a potentially lethal dose (8 Gy) of X-rays when given prior to or after animal irradiation. Pretreatment of animals with antioxidants resulted in significantly higher total white blood cell and neutrophil counts in peripheral blood at 4 and 24 hours following exposure to doses of 1 Gy and 8 Gy. Antioxidant treatment also resulted in increased bone marrow cell counts following irradiation, and prevented peripheral lymphopenia following 1 Gy irradiation. Supplementation with antioxidants in irradiated animals resulted in several gene expression changes: the antioxidant treatment was associated with increased Bcl-2, and decreased Bax, caspase-9 and TGF-β1 mRNA expression in the bone marrow following irradiation. These results suggest that modulation of apoptosis may be mechanistically involved in hematopoietic system radioprotection by antioxidants. Maintenance of the antioxidant diet was associated with improved recovery of the bone marrow following sub-lethal or potentially lethal irradiation. Taken together

  14. Essential Oils from Thyme (Thymus vulgaris): Chemical Composition and Biological Effects in Mouse Model.

    Science.gov (United States)

    Vetvicka, Vaclav; Vetvickova, Jana

    2016-12-01

    Thymus species are popular spices and contain volatile oils as main chemical constituents. Recently, plant-derived essential oils are gaining significant attention due to their significant biological activities. Seven different thymus-derived essential oils were compared in our study. First, we focused on their chemical composition, which was followed up by testing their effects on phagocytosis, cytokine production, chemotaxis, edema inhibition, and liver protection. We found limited biological activities among tested oils, with no correlation between composition and biological effects. Similarly, no oils were effective in every reaction. Based on our data, the tested biological use of these essential oils is questionable.

  15. Effect of Process-Oriented Guided-Inquiry Learning on Non-majors Biology Students' Understanding of Biological Classification

    Science.gov (United States)

    Wozniak, Breann M.

    The purpose of this study was to examine the effect of process-oriented guided-inquiry learning (POGIL) on non-majors college biology students' understanding of biological classification. This study addressed an area of science instruction, POGIL in the non-majors college biology laboratory, which has yet to be qualitatively and quantitatively researched. A concurrent triangulation mixed methods approach was used. Students' understanding of biological classification was measured in two areas: scores on pre and posttests (consisting of 11 multiple choice questions), and conceptions of classification as elicited in pre and post interviews and instructor reflections. Participants were Minnesota State University, Mankato students enrolled in BIOL 100 Summer Session. One section was taught with the traditional curriculum (n = 6) and the other section in the POGIL curriculum (n = 10) developed by the researcher. Three students from each section were selected to take part in pre and post interviews. There were no significant differences within each teaching method (p vs. M = 7.330 +/- .330; z =-1.729, p = .084) and the traditional group may have scored higher on the pretest than the posttest (M = 8.333 +/- .333 vs M = 7.333 +/- .333; z = -1.650 , p = .099). Two themes emerged after the interviews and instructor reflections: 1) After instruction students had a more extensive understanding of classification in three areas: vocabulary terms, physical characteristics, and types of evidence used to classify. Both groups extended their understanding, but only POGIL students could explain how molecular evidence is used in classification. 2) The challenges preventing students from understanding classification were: familiar animal categories and aquatic habitats, unfamiliar organisms, combining and subdividing initial groupings, and the hierarchical nature of classification. The POGIL students were the only group to surpass these challenges after the teaching intervention. This

  16. Biological effects of low-dose ionizing radiation exposure; Biologische Wirkungen niedriger Dosen ionisierender Strahlung

    Energy Technology Data Exchange (ETDEWEB)

    Reinoehl-Kompa, Sabine; Baldauf, Daniela; Heller, Horst (comps.)

    2009-07-01

    The report on the meeting of the Strahlenschutzkommission 2007 concerning biological effects of low-dose ionizing radiation exposure includes the following contributions: Adaptive response. The importance of DNA damage mechanisms for the biological efficiency of low-energy photons. Radiation effects in mammography: the relative biological radiation effects of low-energy photons. Radiation-induced cataracts. Carcinomas following prenatal radiation exposure. Intercellular apoptosis induction and low-dose irradiation: possible consequences for the oncogenesis control. Mechanistic models for the carcinogenesis with radiation-induced cell inactivation: application to all solid tumors in the Japanese atomic bomb survivors. Microarrays at low radiation doses. Mouse models for the analysis of biological effects of low-dose ionizing radiation. The bystander effect: observations, mechanisms and implications. Lung carcinoma risk of Majak workers - modeling of carcinogenesis and the bystander effect. Microbeam studies in radiation biology - an overview. Carcinogenesis models with radiation-induced genomic instability. Application to two epidemiological cohorts.

  17. Radon exposure of the skin: I. Biological effects

    Energy Technology Data Exchange (ETDEWEB)

    Charles, M W [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2007-09-15

    Radon progeny can plate out on skin and give rise to exposure of the superficial epidermis from alpha emitters Po-218 (7.7 MeV, range {approx}66 {mu}m) and Po-214 (6 MeV, range {approx}44 {mu}m). Dose rates from beta/gamma emitters Pb-214 and Bi-214 are low and only predominate at depths in excess of the alpha range. This paper reviews the evidence for a causal link between exposure from radon and its progeny, and deterministic and stochastic biological effects in human skin. Radiation induced skin effects such as ulceration and dermal atrophy, which require irradiation of the dermis, are ruled out for alpha irradiation from radon progeny because the target cells are considerably deeper than the range of alpha particles. They have not been observed in man or animals. Effects such as erythema and acute epidermal necrosis have been observed in a few cases of very high dose alpha particle exposures in man and after acute high dose exposure in animals from low energy beta radiations with similar depth doses to radon progeny. The required skin surface absorbed doses are in excess of 100 Gy. Such effects would require extremely high levels of radon progeny. They would involve quite exceptional circumstances, way outside the normal range of radon exposures in man. There is no definitive identification of the target cells for skin cancer induction in animals or man. The stem cells in the basal layer which maintain the epidermis are the most plausible contenders for target cells. The majority of these cells are near the end of the range of radon progeny alpha particles, even on the thinnest body sites. The nominal depth of these cells, as recommended by the International Commission on Radiological Protection (ICRP), is 70 {mu}m. There is evidence however that some irradiation of the hair follicles and/or the deeper dermis, as well as the inter-follicular epidermis, is also necessary for skin cancer induction. Alpha irradiation of rodent skin that is restricted to the

  18. Radioprotection, biological effects of the radiations and security in the handling of radioactive material

    CERN Document Server

    Teran, M

    2000-01-01

    The development of the philosophy of the radioprotection is dependent on the understanding of the effects of the radiation in the man. Behind the fact that the radiation is able to produce biological damages there are certain factors with regard to the biological effects of the radiations that determine the boarding of the radioprotection topics.

  19. Controlling the Biological Effects of Spermine Using a Synthetic Receptor

    NARCIS (Netherlands)

    Vial, Laurent; Ludlow, R. Frederick; Leclaire, Julien; Pérez-Fernández, Ruth; Otto, Sijbren

    2006-01-01

    Polyamines play an important role in biology, yet their exact function in many processes is poorly understood. Artificial host molecules capable of sequestering polyamines could be useful tools for studying their cellular function. However, designing synthetic receptors with affinities sufficient to

  20. Biological and technological effects of some mulberry varieties and ...

    African Journals Online (AJOL)

    egyptian hak

    Approaches for improving the nutritional wellbeing of humans such as food diversification, supplementation with capsules or syrups, molecular biology and industrial food ... To record growth, yield attributes and yields of corn, five plants were randomly selected ..... FAO (1996) Human vitamin and mineral requirements. No.

  1. Effect of sulphide on enhanced biological phosphorus removal

    NARCIS (Netherlands)

    Rubio Rincon, F.J.

    2017-01-01

    The enhanced biological removal of phosphorus (EBPR) is a popular process due to high removal efficiency, low operational costs, and the possibility of phosphorus recovery. Nevertheless, the stability of the EBPR depends on different factors such as: temperature, pH, and the presence of toxic

  2. Biological Effects of Electromagnetic Radiation. Volume II, Number 4.

    Science.gov (United States)

    1975-12-01

    produce meat cubes and similar ingredients f or p ies , ready meals , and Alan H. Barrett and Philip C. Meyers of MIT have de— canned products. It can also...area and may cause hormonal and biochemical Cross e , Wisc.) and A. Prieto , Jr. Biologic and Cli~— changes . A series of p i l o t hormonal screening

  3. High-intensity focused ultrasound (HIFU) using Sonablate{trade mark, serif} devices for the treatment of localized prostate cancer: 13-year experience

    Science.gov (United States)

    Uchida, Toyoaki; Tomonaga, Tetsuro; Shoji, Sunao; Kim, Hakushi; Nagata, Yoshihiro

    2012-11-01

    To report on the long-term results of high-intensity focused ultrasound (HIFU) in the treatment of localized prostate cancer. Eight hundred and eighty-four men with prostate cancer treated with Sonablate® (SB) devices were included. All patients were followed for more than 2 years. The patients were divided into three groups: in the first group, 419 patients were treated with SB200/500 from 1999 to 2006; in the second group, 263 patients were treated with SB 500 ver. 4 from 2005 to 2009: in the third group, 202 patients were treated with SB 500 TCM from 2007 up to present. Biochemical failure was defined according to the Phoenix definition (PSA nadir + 2 ng/ml). The mean age, PSA, Gleason score, operation time, and follow-up period in each group were 68, 66 and 67 years, 11.2, 9.7 and 9.3 ng/ml, 6.2, 6.6 and 6.7, 167, 101 and 106 min, and 56, 48 and 36 months, respectively. The biochemical disease-free rate (bDFR) in each group at 5 years was, respectively, 54%, 61% and 84%, and was 50% at 10 years in the SB200/500 group (prisk groups in all patients at 10 years were 72% and 58%, 44%, respectively (prisk groups in the SB500 TCM group at 5 years were 97%, 83%, and 74% (p=0.0056). The negative prostate biopsy rates in 3 groups were 81%, 92% and 88%, respectively. As post HIFU complications, urethral stricture, acute epididymitis and urinary incontinence were noted in 18.0%, 6.2% and 1.9%, respectively. Rectourethral fistula was occurred in 0.6% in the first HIFU cases, Postoperative erectile dysfunction was noted in 27% of patients at 2 years after HIFU. HIFU therapy appears to be minimally invasive, efficacious, and safe for patients with localized prostate cancer. Technological advances as well as cultural and economic vectors have caused a shift from to minimally invasive techniques.

  4. Multi-parametric monitoring and assessment of high-intensity focused ultrasound (HIFU) boiling by harmonic motion imaging for focused ultrasound (HMIFU): an ex vivo feasibility study.

    Science.gov (United States)

    Hou, Gary Y; Marquet, Fabrice; Wang, Shutao; Konofagou, Elisa E

    2014-03-07

    Harmonic motion imaging for focused ultrasound (HMIFU) is a recently developed high-intensity focused ultrasound (HIFU) treatment monitoring method with feasibilities demonstrated in vitro and in vivo. Here, a multi-parametric study is performed to investigate both elastic and acoustics-independent viscoelastic tissue changes using the Harmonic Motion Imaging (HMI) displacement, axial compressive strain and change in relative phase shift during high energy HIFU treatment with tissue boiling. Forty three (n = 43) thermal lesions were formed in ex vivo canine liver specimens (n = 28). Two-dimensional (2D) transverse HMI displacement maps were also obtained before and after lesion formation. The same method was repeated in 10 s, 20 s and 30 s HIFU durations at three different acoustic powers of 8, 10, and 11 W, which were selected and verified as treatment parameters capable of inducing boiling using both thermocouple and passive cavitation detection (PCD) measurements. Although a steady decrease in the displacement, compressive strain, and relative change in the focal phase shift (Δϕ) were obtained in numerous cases, indicating an overall increase in relative stiffness, the study outcomes also showed that during boiling, a reverse lesion-to-background displacement contrast was detected, indicating potential change in tissue absorption, geometrical change and/or, mechanical gelatification or pulverization. Following treatment, corresponding 2D HMI displacement images of the thermal lesions also mapped consistent discrepancy in the lesion-to-background displacement contrast. Despite the expectedly chaotic changes in acoustic properties with boiling, the relative change in phase shift showed a consistent decrease, indicating its robustness to monitor biomechanical properties independent of the acoustic property changes throughout the HIFU treatment. In addition, the 2D HMI displacement images confirmed and indicated the increase in the thermal lesion size with

  5. Multi-parametric monitoring and assessment of High Intensity Focused Ultrasound (HIFU) boiling by Harmonic Motion Imaging for Focused Ultrasound (HMIFU): An ex vivo feasibility study

    Science.gov (United States)

    Hou, Gary Y.; Marquet, Fabrice; Wang, Shutao; Konofagou, Elisa E.

    2014-01-01

    Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a recently developed high-intensity focused ultrasound (HIFU) treatment monitoring method with feasibilities demonstrated in vitro and in vivo. Here, a multi-parametric study is performed to investigate both elastic and acoustics-independent viscoelastic tissue changes using the Harmonic Motion Imaging (HMI) displacement, axial compressive strain and change in relative phase-shift during high energy HIFU treatment with tissue boiling. Forty three (n=43) thermal lesions were formed in ex vivo canine liver specimens (n=28). Two dimensional (2D) transverse HMI displacement maps were also obtained before and after lesion formation. The same method was repeated in 10-s, 20-s and 30-s HIFU durations at three different acoustic powers of 8, 10, and 11W, which were selected and verified as treatment parameters capable of inducing boiling using both thermocouple and Passive Cavitation Detection (PCD) measurements. Although a steady decrease in the displacement, compressive strain, and relative change in the focal phase shift (Δφ) were obtained in numerous cases, indicating an overall increase in relative stiffness, the study outcomes also showed that during boiling, a reverse lesion-to-background displacement contrast was detected, indicating potential change in tissue absorption, geometrical change and/or, mechanical gelatification or pulverization. Following treatment, corresponding 2D HMI displacement images of the thermal lesions also mapped consistent discrepancy in the lesion-to-background displacement contrast. Despite unpredictable changes in acoustic properties with boiling, the relative change in phase shift showed a consistent decrease, indicating its robustness to monitor biomechanical properties independent of the acoustic property change throughout the HIFU treatment. In addition, the 2D HMI displacement images confirmed and indicated the increase in the thermal lesion size with treatment duration

  6. K-shell ionization and biological effects; Ionisation en couche K et effet biologique

    Energy Technology Data Exchange (ETDEWEB)

    L' Hoir, A.; Herve du Penhoat, M.A.; Champion, C.; Fayard, B.; Touati, A.; Abel, F.; Politis, M.F.; Chetioui, A. [Paris-7 Univ., 75 (France); Paris-6 Univ., 75 (France); Despiney-Bailly, I. [CEA Bruyeres-le-Chatel, 91 (France); Sabatier, L. [CEA Fontenay-aux-Roses, 92 (France). Direction des Sciences du Vivant

    1998-04-01

    Initial steps of radiation action mechanism on biological targets are still unknown. The strong correlation observed between inactivation cross sections by heavy ions and K-vacancy production cross sections has drawn the attention on this process. Although quite minor in the energy deposition of these particles, the K-ionization process gives rise to quite efficient ionization clusters. Values of K-ionization biological effectivenesses extracted from measured relative biological efficiencies of ultra soft X-rays support the idea of a major -may be a dominant- contribution of the K-vacancy process to the biological effect of heavy ions. (authors)

  7. Biological Effects of Listeriolysin O: Implications for Vaccination

    Directory of Open Access Journals (Sweden)

    K. G. Hernández-Flores

    2015-01-01

    Full Text Available Listeriolysin O (LLO is a thiol-activated cholesterol-dependent pore-forming toxin and the major virulence factor of Listeria monocytogenes (LM. Extensive research in recent years has revealed that LLO exerts a wide array of biological activities, during the infection by LM or by itself as recombinant antigen. The spectrum of biological activities induced by LLO includes cytotoxicity, apoptosis induction, endoplasmic reticulum stress response, modulation of gene expression, intracellular calcium oscillations, and proinflammatory activity. In addition, LLO is a highly immunogenic toxin and the major target for innate and adaptive immune responses in different animal models and humans. Recently, the crystal structure of LLO has been published in detail. Here, we review the structure-function relationship for this fascinating microbial molecule, highlighting the potential uses of LLO in the fields of biomedicine and biotechnology, particularly in vaccination.

  8. Dehydroepiandrosterone biosynthesis, metabolism, biological effects, and clinical use (analytical review)

    OpenAIRE

    Goncharov, N. P.; G. V. Katsiya

    2015-01-01

    The review presents the fundamental information on the metabolism of dehydroepiandrosterone (DHEA), its biological role and possibilities of its use for replacement therapy. There were studied species differences in the synthesis of DHEA in the adrenal cortex. It was found that DHEA and DHEA-sulfate are produced only by the adrenal glands of humans and monkeys, including lower monkeys. Their biosynthesis involves the following steps: cholesterol → pregnenolone → 17-hydroxypregnenolone → DHEA....

  9. Resurrecting the body: Has portmodernism had any effect on biology?

    Science.gov (United States)

    Gilbert, S F

    1995-01-01

    While postmodernism has had very little influence in biology (for reasons discussed in the paper), it can provide a framework for discussing the context in which biology is done. Here, four biological views of the body/self are contrasted: the neural, immunological, genetic, and phenotypic bodies. Each physical view of the body extrapolates into a different model of the body politic, and each posits a different relationship between bodies of knowledge. The neural view of the body models a body politic wherein society is defined by its culture and laws. The genetic view privileges views of polities based on ethnicity and race. The immune body extrapolates into polities that can defend themselves against other such polities. The phenotypic view of the body politic stands in opposition to these three major perspectives and integrates them without giving any predominance. The view of science as a "neural" body of knowledge contends that science is aperspectival and objective. The perspective of the "immune" body is that science exists to defend the interests of its creataors. The genetic view of science is that science is the basis of all culture. The extrapolation of the phenotypic body to science insists upon the utilitarian rationale for scientific interprises. In all instances, the genetic view of the body/body politic/body of science is presently in ascendance.

  10. Integrated Network Analysis and Effective Tools in Plant Systems Biology

    Directory of Open Access Journals (Sweden)

    Atsushi eFukushima

    2014-11-01

    Full Text Available One of the ultimate goals in plant systems biology is to elucidate the genotype-phenotype relationship in plant cellular systems. Integrated network analysis that combines omics data with mathematical models has received particular attention. Here we focus on the latest cutting-edge computational advances that facilitate their combination. We highlight (1 network visualization tools, (2 pathway analyses, (3 genome-scale metabolic reconstruction, and (4 the integration of high-throughput experimental data and mathematical models. Multi-omics data that contain the genome, transcriptome, proteome, and metabolome and mathematical models are expected to integrate and expand our knowledge of complex plant metabolisms.

  11. Biological influences on hydrogen effects in steel in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Edyvean, R.G.J.; Benson, J.; Thomas, C.J. [Univ. of Sheffield (United Kingdom). Dept. of Chemical and Process Engineering; Beech, I.B. [Univ. of Portsmouth (United Kingdom). Dept. of Chemistry; Videla, H.A. [Univ. of La Plata (Argentina). Dept. of Chemistry

    1997-08-01

    Conditions conducive to the enhancement of corrosion-fatigue crack growth and of hydrogen embrittlement can be generated by the activity of sulfate-reducing bacterial. However, while the presence of bacteria encourages more hydrogen entry into susceptible metals when compared to similar levels of sulfide generated abiotically, corrosion-fatigue crack growth rates are slower in biological environments than the equivalent abiological environment. These results are discussed in the light of recent findings on the enhancement and inhibition of surface corrosion by bacterial biofilms.

  12. Effects of outside air temperature on the preparation of antineoplastic drug solutions in biological safety cabinets.

    Science.gov (United States)

    Umemura, Masayuki; Itoh, Akio; Ando, Yuichi; Yamada, Kiyofumi; Wakiya, Yoshifumi; Nabeshima, Toshitaka

    2015-08-01

    In Japan, biological safety cabinets are commonly used by medical staff to prepare antineoplastic agents. At the Division of Chemotherapy for Outpatients, Nagoya University Hospital, a class II B2 biological safety cabinet is used. The temperature inside this biological safety cabinet decreases in winter. In this study, we investigated the effect of low outside air temperature on the biological safety cabinet temperature, time required to admix antineoplastic agents, and accuracy of epirubicin weight measurement. Studies were conducted from 1 January to 31 March 2008 (winter). The outside air temperature near the biological safety cabinet intake nozzle was compared with the biological safety cabinet temperature. The correlation between the outside air temperature and the biological safety cabinet temperature, time for cyclophosphamide and gemcitabine solubilization, and accuracy of epirubicin weight measurement were investigated at low and high biological safety cabinet temperatures. The biological safety cabinet temperature correlated with the outside air temperature of 5-20℃ (p antineoplastic agents. We suggest that a decrease in biological safety cabinet temperature may increase the time required to admix antineoplastic agents, thereby increasing the time for which outpatients must wait for chemotherapy. © The Author(s) 2014.

  13. Gender Inequality in Biology Classes in China and Its Effects on Students' Short-Term Outcomes

    Science.gov (United States)

    Liu, Ning; Neuhaus, Birgit

    2014-01-01

    This study investigated gender inequality in biology lessons and analysed the effects of the observed inequality on students' short-term knowledge achievement, situational interest and students' evaluation of teaching (SET). Twenty-two biology teachers and 803 7th-grade students from rural and urban classrooms in China participated in the study.…

  14. A Study of the Probe Effect on the Apparent Image of Biological Atomic Force Microscopy

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The probe effect on the apparent image of biological atomic force microscopy was explored in this study, and the potential of AFM in conformational study of gene related biological processes was illustrated by the specific nanostructural information of a new antitumor drug binding to DNA.

  15. Indirect ecological effects in invaded landscapes: Spillover and spillback from biological control agents to native analogues

    Science.gov (United States)

    Biological control remains an effective option for managing large-scale weed problems in natural areas. The predation or parasitism of biological control agents by other species present in the introduced range (biotic resistance) is well studied and is often cited as the cause for a lack of establis...

  16. Adverse effects of biologics: a network meta-analysis and Cochrane overview

    DEFF Research Database (Denmark)

    Singh, J. A.; Wells, G. A.; Christensen, Robin Daniel Kjersgaard

    2011-01-01

    Background Biologics are used for the treatment of rheumatoid arthritis and many other conditions. While the efficacy of biologics has been established, there is uncertainty regarding the adverse effects of this treatment. Since serious risks such as tuberculosis (TB) reactivation, serious infect...

  17. Biological Effects of TMPRSS2/ERG Fusion Isoforms in Human Prostate Cancer

    Science.gov (United States)

    2009-02-01

    TITLE: Biological Effects of TMPRSS2/ERG Fusion Isoforms in Human Prostate Cancer PRINCIPAL INVESTIGATOR: Jianghua Wang, M.D...6 JAN 2009 / / /4. TITLE AND SUBTITLE Biological Effects of TMPRSS2/ERG Fusion Isoforms in Human Prostate Cancer 5a. CONTRACT NUMBER W81XWH...quantitative RT-PCR arrays we have identified candidate mediators of these phenotypic effects . We propose to extend these studies to primary prostate epithelial

  18. Biological effects of an impulse current according to laboratory researches of electroshock devices

    Directory of Open Access Journals (Sweden)

    Grigoryev О.A.

    2013-12-01

    Full Text Available The federal law "About Weapons" permits the use of electroshock devices if they are safe for people. We developed requirements for the procedure medical-biological testing on the safety of electroshock devices. We did an experimental study assessing medical-biological safety of electroshock devices. The assessment is based on a point system, which use ranges of biological effects. The experiments were performed in rabbits. We used 13 electroshock devices with different characteristics. Electroshock devices were made in Russia. We found that the response of a biological object to inrush current included convulsions, respiratory and cardiac activity. We analyzed the biological effects of pulsed current electroshock device obtained in experimental conditions. It is concluded that the characteristic clinical and physiological response to the action of electric current is pulsepolyparametric and depending on a combination of characteristics and condition of the electric impulse influence object.

  19. Biological methanogenesis and the CO2 greenhouse effect

    Science.gov (United States)

    Guthrie, P. D.

    1986-01-01

    It is well established that plants tend to increase net photosynthesis under increased carbon dioxide. It is also well established that a large fraction of atmospheric methane is produced by microbial metabolism of organic sediments in paddies and freshwater wetlands, where a major source of organic debris is local plant growth. As CO2 increases, it may lead to increased methane production and a resulting enhancement of the expected greenhouse warming. A rough estimate of the present rate of this biologically mediated feedback on the climate system indicates that it might account for as much as 30 percent of the observed methane increase and speed up the greenhouse forcing by as much as 15 percent.

  20. Effects of Oxidative Stress on Mesenchymal Stem Cell Biology

    Science.gov (United States)

    2016-01-01

    Mesenchymal stromal/stem cells (MSCs) are multipotent stem cells present in most fetal and adult tissues. Ex vivo culture-expanded MSCs are being investigated for tissue repair and immune modulation, but their full clinical potential is far from realization. Here we review the role of oxidative stress in MSC biology, as their longevity and functions are affected by oxidative stress. In general, increased reactive oxygen species (ROS) inhibit MSC proliferation, increase senescence, enhance adipogenic but reduce osteogenic differentiation, and inhibit MSC immunomodulation. Furthermore, aging, senescence, and oxidative stress reduce their ex vivo expansion, which is critical for their clinical applications. Modulation of sirtuin expression and activity may represent a method to reduce oxidative stress in MSCs. These findings have important implications in the clinical utility of MSCs for degenerative and immunological based conditions. Further study of oxidative stress in MSCs is imperative in order to enhance MSC ex vivo expansion and in vivo engraftment, function, and longevity. PMID:27413419

  1. Dehydroepiandrosterone biosynthesis, metabolism, biological effects, and clinical use (analytical review

    Directory of Open Access Journals (Sweden)

    N. P. Goncharov

    2015-04-01

    Full Text Available The review presents the fundamental information on the metabolism of dehydroepiandrosterone (DHEA, its biological role and possibilities of its use for replacement therapy. There were studied species differences in the synthesis of DHEA in the adrenal cortex. It was found that DHEA and DHEA-sulfate are produced only by the adrenal glands of humans and monkeys, including lower monkeys. Their biosynthesis involves the following steps: cholesterol → pregnenolone → 17-hydroxypregnenolone → DHEA. The adrenal glands of other species, including rats and mice do not synthesize DHEA. At the same time, in certain brain structures not only in man and monkey, but also in other animals DHEA and its precursors are synthesized de novo which are denoted as neurosteroids. It was demonstrated that Purkinje cells which play an important role in memory formation and learning are mainly place neurosteroid formation in mammals and other vertebrates. To establish the relationship of age and the level of DHEA and other steroids we studied the dynamics of their levels at different periods of postnatal development of people. Peak concentration DHEA observed in aged 25–30 years. In the interval from 20 to 90 years in humans the level falls approximately for 90 %. Cortisol levels in blood does not vary with age, leading to an imbalance in the ratio of cortisol/DHEA. Proved a major role of DHEA as a source (precursor for the synthesis of biologically active sex steroids – testosterone, estradiol and estrone in peripheral tissues. This review presents the bioavailability of DHEA in various physiological and pathological processes in humans and animals. In animal experiments has shown a higher bioavailability of DHEA in transdermal administration as compared with oral administration as in this case there is no steroid rapid inactivation in the liver during its first passage. According to recent studies there is a pronounced dependence of bioavailability of DHEA

  2. Dehydroepiandrosterone biosynthesis, metabolism, biological effects, and clinical use (analytical review

    Directory of Open Access Journals (Sweden)

    N. P. Goncharov

    2015-01-01

    Full Text Available The review presents the fundamental information on the metabolism of dehydroepiandrosterone (DHEA, its biological role and possibilities of its use for replacement therapy. There were studied species differences in the synthesis of DHEA in the adrenal cortex. It was found that DHEA and DHEA-sulfate are produced only by the adrenal glands of humans and monkeys, including lower monkeys. Their biosynthesis involves the following steps: cholesterol → pregnenolone → 17-hydroxypregnenolone → DHEA. The adrenal glands of other species, including rats and mice do not synthesize DHEA. At the same time, in certain brain structures not only in man and monkey, but also in other animals DHEA and its precursors are synthesized de novo which are denoted as neurosteroids. It was demonstrated that Purkinje cells which play an important role in memory formation and learning are mainly place neurosteroid formation in mammals and other vertebrates. To establish the relationship of age and the level of DHEA and other steroids we studied the dynamics of their levels at different periods of postnatal development of people. Peak concentration DHEA observed in aged 25–30 years. In the interval from 20 to 90 years in humans the level falls approximately for 90 %. Cortisol levels in blood does not vary with age, leading to an imbalance in the ratio of cortisol/DHEA. Proved a major role of DHEA as a source (precursor for the synthesis of biologically active sex steroids – testosterone, estradiol and estrone in peripheral tissues. This review presents the bioavailability of DHEA in various physiological and pathological processes in humans and animals. In animal experiments has shown a higher bioavailability of DHEA in transdermal administration as compared with oral administration as in this case there is no steroid rapid inactivation in the liver during its first passage. According to recent studies there is a pronounced dependence of bioavailability of DHEA

  3. Biological Effects of Laser Radiation. Volume I. Review of the Literature on Biological Effects of Laser Radiation-to 1965.

    Science.gov (United States)

    1978-10-17

    Microbeam 51 7. Embryology 82 8. Studies on Normal Animals 91 9. Tumor Studies 159 10. Clinical Studies 188 11. Ophthalmology 232 12. Dental Studies 263...o f e:xnosures 7wacs cad st. Cn3 side of the lesion was Mnainted w-ith 1 7=ns blue. I-oia=io wsCarried out in a fch.eck-er- boar-d ditiuinZt 1...ocular structures. Abstr. - Biological sessions - Boston laser conference, Northeastern University, Boston, Mass. Aug 5-7, 1964. 53. Polyak , S.L.: The

  4. Risk of serious adverse effects of biological and targeted drugs in patients with rheumatoid arthritis

    DEFF Research Database (Denmark)

    Tarp, Simon; Eric Furst, Daniel; Boers, Maarten

    2016-01-01

    OBJECTIVES: To determine possible differences in serious adverse effects among the 10 currently approved biological and targeted synthetic DMARDs (b/ts-DMARDs) for RA. METHODS: Systematic review in bibliographic databases, trial registries and websites of regulatory agencies identified randomized...

  5. Sequestration of mitochondrial iron by silica particles initiates a biological effect.

    Science.gov (United States)

    Summary Inhalation of particulate matter has presented a challenge to human health for thousands of years. The underlying mechanism for biological effect following particle exposure is incompletely understood. We tested the postulate that particle sequestration of cell and mit...

  6. Effects of cage fish culture on water quality and selected biological ...

    African Journals Online (AJOL)

    Effects of cage fish culture on water quality and selected biological ... varied spatially and temporally but were generally within safe ranges for freshwater habitats. ... and depressed zooplankton diversity at WC suggested impacts from the fish ...

  7. Professional development strategies for teaching urban biology teachers to use concept maps effectively

    Science.gov (United States)

    McGregor Petgrave, Dahlia M.

    Many teachers are not adequately prepared to help urban students who have trouble understanding conceptual ideas in biology because these students have little connection to the natural world. This study explored potential professional development strategies to help urban biology teachers use concept maps effectively with various topics in the biology curriculum. A grounded theory approach was used to develop a substantive professional development model for urban biology teachers. Qualitative data were collected through 16 semi-structured interviews of professional developers experienced in working with concept maps in the urban context. An anonymous online survey was used to collect quantitative data from 56 professional developers and teachers to support the qualitative data. The participants were from New York City, recruited through the NY Biology-Chemistry Professional Development Mentor Network and the NY Biology Teachers' Association. According to the participants, map construction, classroom applications, lesson planning, action research, follow-up workshops, and the creation of learning communities are the most effective professional development strategies. The interviewees also proposed English language learning strategies such as picture maps, native word maps, and content reading materials with underlined words. This study contributes to social change by providing a professional development model to use in planning workshops for urban teachers. Urban teachers improve their own conceptual understanding of biology while learning how to implement concept mapping strategies in the classroom. Students whose teachers are better prepared to teach biology in a conceptual manner have the potential of growing into more scientifically literate citizens.

  8. Effectiveness and biological compatibility of different generations of dentin adhesives.

    Science.gov (United States)

    da Silva, João M F; Rodrigues, José R; Camargo, Carlos H R; Fernandes, Virgilio Vilas Boas; Hiller, Karl-Anton; Schweikl, Helmut; Schmalz, Gottfried

    2014-01-01

    Besides possessing good mechanical properties, dental materials should present a good biological behavior and should not injure the involved tissues. Bond strength and biocompatibility are both highly significant properties of dentin adhesives. For that matter, these properties of four generations of adhesive systems (Multi-Purpose/Single Bond/SE Plus/Easy Bond) were evaluated. Eighty bovine teeth had their dentin exposed (500- and 200-μm thickness). Adhesive was applied on the dentin layer of each specimen. Following that, the microshearing test was performed for all samples. A dentin barrier test was used for the cytotoxicity evaluation. Cell cultures (SV3NeoB) were collected from testing materials by means of 200- or 500-μm-thick dentin slices and placed in a cell culture perfusion chamber. Cell viability was measured 24 h post-exposition by means of a photometrical test (MTT test). The best bonding performance was shown by the single-step adhesive Easy Bond (21 MPa, 200 μm; 27 MPa, 500 μm) followed by Single Bond (15.6 MPa, 200 μm; 23.4 MPa, 500 μm), SE Plus (18.2 MPa, 200 μm; 20 MPa, 500 μm), and Multi-Purpose (15.2 MPa, 200 μm; 17.9 MPa, 500 μm). Regarding the cytotoxicity, Multi-Purpose slightly reduced the cell viability to 92% (200 μm)/93% (500 μm). Single Bond was reasonably cytotoxic, reducing cell viability to 71% (200 μm)/64% (500 μm). The self-etching adhesive Scotchbond SE decreased cell viability to 85% (200 μm)/71% (500 μm). Conversely, Easy Bond did not reduce cell viability in this test, regardless of the dentin thickness. Results showed that the one-step system had the best bond strength performance and was the least toxic to pulp cells. In multiple-step systems, a correct bonding technique must be done, and a pulp capping strategy is necessary for achieving good performance in both properties. The study showed a promising system (one-step self-etching), referring to it as a good alternative for specific cases, mainly due to its

  9. The role of biological rates in the simulated warming effect on oceanic CO2 uptake

    Science.gov (United States)

    Cao, Long; Zhang, Han

    2017-05-01

    Marine biology plays an important role in the ocean carbon cycle. However, the effect of warming-induced changes in biological rates on oceanic CO2 uptake has been largely overlooked. We use an Earth system model of intermediate complexity to investigate the effect of temperature-induced changes in biological rates on oceanic uptake of atmospheric CO2 and compare it with the effects from warming-induced changes in CO2 solubility and ocean mixing and circulation. Under the representative CO2 concentration pathway RCP 8.5 and its extension, by year 2500, relative to the simulation without warming effect on the ocean carbon cycle, CO2-induced warming reduces cumulative oceanic CO2 uptake by 469 Pg C, of which about 20% is associated with the warming-induced change in marine biological rates. In our simulations, the bulk effect of biological-mediated changes on CO2 uptake is smaller than that mediated by changes in CO2 solubility and ocean mixing and circulation. However, warming-induced changes in individual biological rates, including phytoplankton growth, phytoplankton mortality, and detritus remineralization, are found to affect oceanic CO2 uptake by an amount greater than or comparable to that caused by changes in CO2 solubility and ocean physics. Our simulations, which include only a few temperature-dependent biological processes, demonstrate the important role of biological rates in the oceanic CO2 uptake. In reality, many more complicated biological processes are sensitive to temperature change, and their responses to warming could substantially affect oceanic uptake of atmospheric CO2.

  10. Bioaccumulation and biological effects in the earthworm Eisenia fetida exposed to natural and depleted uranium

    Energy Technology Data Exchange (ETDEWEB)

    Giovanetti, Anna, E-mail: anna.giovanetti@enea.i [ENEA, Institute of Radiation Protection, CR Casaccia Via Anguillarese 301, 00123 Rome (Italy); Fesenko, Sergey [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria); Cozzella, Maria L. [ENEA, National Institute for Metrology of Ionizing Radiation, CR Casaccia Via Anguillarese 301, 00123 Rome (Italy); Asencio, Lisbet D. [Centro de Estudios Ambientales, Carretera a Castillo de Jagua, CP. 59350 C. Nuclear, Cienfuegos (Cuba); Sansone, Umberto [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria)

    2010-06-15

    The accumulations of both natural (U) and depleted (DU) uranium in the earthworms (Eisenia fetida) were studied to evaluate corresponding biological effects. Concentrations of metals in the experimental soil ranged from 1.86 to 600 mg kg{sup -1}. Five biological endpoints: mortality, animals' weight increasing, lysosomal membrane stability by measuring the neutral red retention time (the NRRT), histological changes and genetic effects (Comet assay) were used to evaluate biological effects in the earthworms after 7 and 28 days of exposure. No effects have been observed in terms of mortality or weight reduction. Cytotoxic and genetic effects were identified at quite low U concentrations. For some of these endpoints, in particular for genetic effects, the dose (U concentration)-effect relationships have been found to be non-linear. The results have also shown a statistically significant higher level of impact on the earthworms exposed to natural U compared to depleted U.

  11. III. Biological effects of radiation from external and internal sources

    Energy Technology Data Exchange (ETDEWEB)

    Stone, R.S.

    1948-05-24

    This report focuses on the hemotological effects of total body irradiation from external and internal sources observed in patients treated for arthritis with radioactive phosphorus administered intravenously.

  12. Soil degradation effect on biological activity in Mediterranean calcareous soils

    Science.gov (United States)

    Roca-Pérez, L.; Alcover-Sáez, S.; Mormeneo, S.; Boluda, R.

    2009-04-01

    Soil degradation processes include erosion, organic matter decline, compaction, salinization, landslides, contamination, sealing and biodiversity decline. In the Mediterranean region the climatological and lithological conditions, together with relief on the landscape and anthropological activity are responsible for increasing desertification process. It is therefore considered to be extreme importance to be able to measure soil degradation quantitatively. We studied soil characteristics, microbiological and biochemical parameters in different calcareous soil sequences from Valencia Community (Easter Spain), in an attempt to assess the suitability of the parameters measured to reflect the state of soil degradation and the possibility of using the parameters to assess microbiological decline and soil quality. For this purpose, forest, scrubland and agricultural soil in three soil sequences were sampled in different areas. Several sensors of the soil biochemistry and microbiology related with total organic carbon, microbial biomass carbon, soil respiration, microorganism number and enzyme activities were determined. The results show that, except microorganism number, these parameters are good indicators of a soil biological activity and soil quality. The best enzymatic activities to use like indicators were phosphatases, esterases, amino-peptidases. Thus, the enzymes test can be used as indicators of soil degradation when this degradation is related with organic matter losses. There was a statistically significant difference in cumulative O2 uptake and extracellular enzymes among the soils with different degree of degradation. We would like to thank Spanish government-MICINN for funding and support (MICINN, project CGL2006-09776).

  13. Medical-biological aspects of radiation effects in Daphnia magna

    Science.gov (United States)

    Sarapultseva, E.; Uskalova, D.; Savina, N.; Ustenko, K.

    2017-01-01

    We have shown that γ-irradiation at doses of 100 and 1000 mGy significantly compromised fecundity and reproductive success of the directly exposed D. magna. These effects were also observed among the non-exposed first-generation progeny of irradiated parents, thus implying the manifestation of transgenerational effects in Daphnia. We have also shown that compromised viability of irradiated D. magna can be attributed cytotoxic effects of irradiation. It would therefore appear that the compromised viability may be attributed to the cytotoxic effects resulted from epigenetic changes affecting some metabolic pathways involved in detoxification of free-radicals. Additionally we have analyzed more distant progeny of irradiated at doses of 10, 100 and 1000 mGy Daphnia. Our data demonstrated that multicellular crustacean D. magna represent a very useful experimental model for analyse of long-term effects of ionising radiation at the organismal level.

  14. Sensitivity analysis of the relative biological effectiveness predicted by the local effect model.

    Science.gov (United States)

    Friedrich, T; Grün, R; Scholz, U; Elsässer, T; Durante, M; Scholz, M

    2013-10-07

    The relative biological effectiveness (RBE) is a central quantity in particle radiobiology and depends on many physical and biological factors. The local effect model (LEM) allows one to predict the RBE for radiobiologic experiments and particle therapy. In this work the sensitivity of the RBE on its determining factors is elucidated based on monitoring the RBE dependence on the input parameters of the LEM. The relevance and meaning of all parameters are discussed within the formalism of the LEM. While most of the parameters are fixed by experimental constraints, one parameter, the threshold dose Dt, may remain free and is then regarded as a fit parameter to the high LET dose response curve. The influence of each parameter on the RBE is understood in terms of theoretic considerations. The sensitivity analysis has been systematically carried out for fictitious in vitro cell lines or tissues with α/β = 2 Gy and 10 Gy, either irradiated under track segment conditions with a monoenergetic beam or within a spread out Bragg peak. For both irradiation conditions, a change of each of the parameters typically causes an approximately equal or smaller relative change of the predicted RBE values. These results may be used for the assessment of treatment plans and for general uncertainty estimations of the RBE.

  15. The biological effects of five feline IFN-alpha subtypes.

    Science.gov (United States)

    Baldwin, Susan L; Powell, Tim D; Sellins, Karen S; Radecki, Steven V; Cohen, J John; Milhausen, Michael J

    2004-06-01

    IFN-alpha has been shown to induce both antiviral and antiproliferative activities in animals. This report describes the biological activity of five recently identified feline IFN-alpha subtypes expressed in the Chinese hamster ovary (CHO) cell line (rfeIFN-alpha1[CHO], rfeIFN-alpha2[CHO], rfeIFN-alpha3[CHO], rfeIFN-alpha5[CHO] and rfeIFN-alpha6[CHO]) and the feIFN-alpha6 subtype expressed in and purified from Pichia pastoris (rfeIFN-alpha6[P. pastoris]). The rfeIFN-alpha[CHO] subtypes were tested for antiviral activity against either Vesicular stomatitis virus (VSV) or feline calicivirus (FCV) infected feline embryonic fibroblast cell line (AH927) or Crandell feline kidney cell line (CRFK). Antiviral activity was induced against both VSV and FCV infected AH927 cells and VSV infected CRFK cells by all five of the rfeIFN-alpha[CHO] subtypes and rfeIFN-alpha6[P. pastoris]. In addition, the IFN-alpha inducible Mx gene (associated with antiviral activity) was upregulated in vivo 24 h following treatment with rfeIFN-alpha6[P. pastoris], compared to baseline levels seen prior to treatment. All of the rfeIFN-alpha[CHO] subtypes and rfeIFN-alpha6[P. pastoris] exhibited antiproliferative activity in the FeT-J cell line (an IL-2 independent feline T-cell line). Both necrosis and apoptosis were observed in rfeIFN-alpha6[P. pastoris]-treated FeT-J cells. The rfeIFN-alpha3[CHO] subtype consistently exhibited lower antiviral and antiproliferative activity compared to that observed with the other four rfeIFN-alpha[CHO] subtypes. In summary, this paper demonstrates that five previously described feIFN-alpha subtypes induce both antiviral and antiproliferative activities in vitro and are capable of upregulating the feMx gene in vivo.

  16. Biological and technological effects of some mulberry varieties and ...

    African Journals Online (AJOL)

    egyptian hak

    Plant growth, yield attributes, yield and net ... nutrient cycle in agro-ecosystems, and could be utilized along with chemical fertilizers. ..... Choudhury ATMA & Khanif YM (2001) Evaluation of the effects of nitrogen and magnesium fertilization on ...

  17. MICROWAVE SYSTEM FOR RESEARCH BIOLOGICAL EFFECTS ON LABORATORY ANIMALS

    OpenAIRE

    Kopylov, Alexei; Kruglik, Olga; Khlebopros, Rem

    2014-01-01

    This research is concerned with development of the microwave system for research the radiophysical microwave radiation effects on laboratory animals. The frequency was 1 GHz. The results obtained demonstrate the metabolic changes in mice under the electromagnetic field influence.

  18. Radioprotective effect and other biological benefits associated with ...

    African Journals Online (AJOL)

    fields including military, medicine, agriculture and industry. As a result, humans ... plant stems, leaves, and fruits, and generally exist in the plant ... effects of bailcalein on DNA damage in irradiated mice. The study ..... electric current production.

  19. Psychological Effects towards Humans Living in the Environment Made of Biological Concrete in Malaysia at 2015

    Directory of Open Access Journals (Sweden)

    Amirreza Talaiekhozani

    2017-01-01

    Full Text Available In day-to-day life concrete become a compulsory material in the construction field as to make it a real concern among researchers for producing concrete with improved properties. Biological method is one of the new methods to improve concrete properties. Although, much research about biological concrete has been carried out, but till now nobody has not studied for the psychological effects of using a house or offices made up of biological concrete. The aim of this study is to investigate and find out the person's opinion about staying in a house or offices made up of biological concrete. In this study, a questionnaire containing eight questions was prepared and distributed among 21 persons in Malaysia University of Technology including students, academic and non-academic staffs among which few of them was an expert in the field of biological concrete and others did not have any knowledge about the bioconcrete. Finally, the results obtained from the questionnaires were analyzed. The results showed that 81% of participants in this study would like to stay in a house or office made up of biological concrete. However, 38% of participants believe that staying in a house or office made of biological concrete can cause health related problems. The current research paper can be considered significant for architects and civil engineers to have the insight to look into the psychological aspects of using biological concrete for various applications in the field of construction.

  20. Examining the effects of students' classroom expectations on undergraduate biology course reform

    Science.gov (United States)

    Hall, Kristi Lyn

    In this dissertation, I perform and compare three studies of introductory biology students' classroom expectations -- what students expect to be the nature of the knowledge that they are learning, what they think they should be (or are) doing in order to learn, and what they think they should be (or are) doing in order to be successful. Previous work has shown that expectations can impact how students approach learning, yet biology education researchers have been reluctant to acknowledge or address the effects of student expectations on curricular reform (NRC, 2012). Most research in biology education reform has focused on students' conceptual understandings of biology and the efficacy of specific changes to content and pedagogy. The current research is lacking a deeper understanding of how students perceive the classroom environment and how those perceptions can shape students' interactions with the content and pedagogy. For present and future reforms in biology to reach their full potential, I argue that biology education should actively address the different ways students think about and approach learning in biology classes. The first study uses a Likert-scale instrument, adapted from the Maryland Physics Expectations Survey (Redish, Saul, & Steinberg, 1998). This new survey, the Maryland Biology Expectations Survey (MBEX) documents two critical results in biology classrooms: (i) certain student-centered pedagogical contexts can produce favorable changes in students' expectations, and (ii) more traditional classroom contexts appear to produce negative epistemological effects. The second study utilizes a modified version of the MBEX and focuses on students' interdisciplinary views. This study documents that: (i) biology students have both discipline-specific and context-specific classroom expectations, (ii) students respond more favorably to interdisciplinary content in the biology courses we surveyed (as opposed to biology content introduced into the physics

  1. A theoretical framework for biological control of soil-borne plant pathogens: Identifying effective strategies.

    Science.gov (United States)

    Cunniffe, Nik J; Gilligan, Christopher A

    2011-06-07

    We develop and analyse a flexible compartmental model of the interaction between a plant host, a soil-borne pathogen and a microbial antagonist, for use in optimising biological control. By extracting invasion and persistence thresholds of host, pathogen and biological control agent, performing an equilibrium analysis, and numerical investigation of sensitivity to parameters and initial conditions, we determine criteria for successful biological control. We identify conditions for biological control (i) to prevent a pathogen entering a system, (ii) to eradicate a pathogen that is already present and, if that is not possible, (iii) to reduce the density of the pathogen. Control depends upon the epidemiology of the pathogen and how efficiently the antagonist can colonise particular habitats (i.e. healthy tissue, infected tissue and/or soil-borne inoculum). A sharp transition between totally effective control (i.e. eradication of the pathogen) and totally ineffective control can follow slight changes in biologically interpretable parameters or to the initial amounts of pathogen and biological control agent present. Effective biological control requires careful matching of antagonists to pathosystems. For preventative/eradicative control, antagonists must colonise susceptible hosts. However, for reduction in disease prevalence, the range of habitat is less important than the antagonist's bulking-up efficiency.

  2. Biological effects of lysophosphatidic acid in the nervous system.

    Science.gov (United States)

    Frisca, Frisca; Sabbadini, Roger A; Goldshmit, Yona; Pébay, Alice

    2012-01-01

    Lysophosphatidic acid (LPA) is a bioactive lipid that regulates a broad range of cellular effects in various cell types, leading to a variety of responses in tissues, including in the nervous system. LPA and its receptors are found in the nervous system, with different cellular and temporal profiles. Through its ability to target most cells of the nervous system and its induction of pleiotropic effects, LPA mediates events during neural development and adulthood. In this review, we summarize the current knowledge on the effects of LPA in the nervous system, during development and adulthood, and in various pathologies of the nervous system. We also explore potential LPA intervention strategies for anti-LPA therapeutics.

  3. Which chemicals drive biological effects in wastewater and recycled water?

    Science.gov (United States)

    Tang, Janet Y M; Busetti, Francesco; Charrois, Jeffrey W A; Escher, Beate I

    2014-09-01

    Removal of organic micropollutants from wastewater during secondary treatment followed by reverse osmosis and UV disinfection was evaluated by a combination of four in-vitro cell-based bioassays and chemical analysis of 299 organic compounds. Concentrations detected in recycled water were below the Australian Guidelines for Water Recycling. Thus the detected chemicals were considered not to pose any health risk. The detected pesticides in the wastewater treatment plant effluent and partially advanced treated water explained all observed effects on photosynthesis inhibition. In contrast, mixture toxicity experiments with designed mixtures containing all detected chemicals at their measured concentrations demonstrated that the known chemicals explained less than 3% of the observed cytotoxicity and less than 1% of the oxidative stress response. Pesticides followed by pharmaceuticals and personal care products dominated the observed mixture effects. The detected chemicals were not related to the observed genotoxicity. The large proportion of unknown toxicity calls for effect monitoring complementary to chemical monitoring.

  4. Some features of irradiated chitosan and its biological effect

    Energy Technology Data Exchange (ETDEWEB)

    Hai, Le; Hien, Nguyen Quoc; Luan, Le Quang; Hanh, Truong Thi; Man, Nguyen Tan; Ha, Pham Thi Le; Thuy, Tran Thi [Nuclear Research Institute, VAEC, Dalat (Viet Nam); Yoshii, Fumio; Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2001-03-01

    Preparation of chitosan oligomer by radiation degradation was carried out on the gamma Co-60 source. The radiation degradation yield (G{sub d}) of the chitosan was found to be of 1.03. The oligochitosan with 50% of dp>8 fraction was obtained by irradiating the 10% (w/v) chitosan solution in 5% acetic acid at 45 kGy for the chitosan having the initial viscometric average molecular weight, Mv=60,000. Irradiated chitosan showed higher antifungal effect than that of unirradiated one. Furthermore, the irradiated chitosan also showed the growth-promotion effect for plants. (author)

  5. Electrical and Biological Effects of Transmission Lines: A Review.

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jack M.

    1989-06-01

    This review describes the electrical properties of a-c and d-c transmission lines and the resulting effects on plants, animals, and people. Methods used by BPA to mitigate undesirable effects are also discussed. Although much of the information in this review pertains to high-voltage transmission lines, information on distribution lines and electrical appliances is included. The electrical properties discussed are electric and magnetic fields and corona: first for alternating-current (a-c) lines, then for direct current (d-c).

  6. Effect of solids retention time and wastewater characteristics on biological phosphorus removal

    DEFF Research Database (Denmark)

    Henze, Mogens; Aspegren, H.; Jansen, J.l.C.

    2002-01-01

    The paper deals with the effect of wastewater, plant design and operation in relation to biological nitrogen and phosphorus removal and the possibilities to model the processes. Two Bio-P pilot plants were operated for 2.5 years in parallel receiving identical wastewater. The plants had SRT of 4...... with time which has importance in relation to modelling. The overall conclusion of the comparison between the two plants is that the biological phosphorus removal efficiency under practical operating conditions is affected by the SRT in the plant and the wastewater composition. Thus great care should...... in verification of models for Nitrogen and Enhanced Biological Phosphorus Removal....

  7. Investigations on the heating effect of PE-LD induced by high-intensity focused ultrasound.

    Science.gov (United States)

    Oehm, Lukas; Bach, Sascha; Majschak, Jens-Peter

    2016-08-01

    High-intensity focused ultrasound is widely applied in tissue treatment as well as for heating of solid polymer materials. Previous studies investigating the heating effect in polymer materials utilized sound transmission through water or other fluids at low HIFU power. In this study, the ultrasonic transducer possesses a solid sound conductor made of aluminum and a high HIFU power of above 100W was applied to heat solid PE-LD samples. Temperature measurements were performed by calibrated non-invasive infrared thermal imaging. A strong heating effect with heating above melting temperature and evaporation temperature within less than 1s of irradiation was observed. Furthermore, the acoustic coupling defined by the force applied by the ultrasonic applicator to the polymer material was found to be fundamental to induce the heating effect. This investigation reveals HIFU for new applications in the field of polymer processing.

  8. Biological effects of ionizing radiations; Effets biologiques des rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Nenot, J.C. [CEA Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire]|[Commission Internationale de protection radiologique (France)]|[Association Internationale de Radiopathologie (France)

    1999-01-01

    Since ten years the ionizing radiations are more and more often used in various domains as medical, industrial or research sector. In the same way, these radiation impacts on the environment and the living organisms, have been studied intensively. The effects mechanism knowledge improved considerably and allowed to better protect the workers and the public. (A.L.B.)

  9. Biological Effects of Electromagnetic Fields on Cellular Growth

    Science.gov (United States)

    Eftekhari, Beheshte; Wilson, James; Masood, Samina

    2012-10-01

    The interaction of organisms with environmental magnetic fields at the cellular level is well documented, yet not fully understood. We review the existing experimental results to understand the physics behind the effects of ambient magnetic fields on the growth, metabolism, and proliferation of in vitro cell cultures. Emphasis is placed on identifying the underlying physical principles responsible for alterations to cell structure and behavior.

  10. Biological and technological effects of some mulberry varieties and ...

    African Journals Online (AJOL)

    egyptian hak

    albino rats over two and five days, and also the effects of a two-week recovery period. Methomyl ... rabbits at a dose of 10 mg/kg body wt for seven days produced significant decrease in red blood cell ... role of vitamins on Japanese quails.

  11. Biological and technological effects of some mulberry varieties and ...

    African Journals Online (AJOL)

    egyptian hak

    The effect of light intensities (1500-6000 lux) and temperature (20-40 ... harvested in the exponential phase of growth by pelleting at high speed (8000 rpm) for 20 .... Figure 3: Biocidal activity (measured as zone of inhibition) of crude extract of ...

  12. Nanoscaled biological gated field effect transistors for cytogenetic analysis

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Dimaki, Maria; Andersen, Karsten Brandt;

    2014-01-01

    Cytogenetic analysis is the study of chromosome structure and function, and is often used in cancer diagnosis, as many chromosome abnormalities are linked to the onset of cancer. A novel label free detection method for chromosomal translocation analysis using nanoscaled field effect transistors...

  13. Resource Letter BELFEF-1: Biological effects of low-frequency electromagnetic fields

    Science.gov (United States)

    Hafemeister, David

    1996-08-01

    This Resource Letter provides a guide to the literature on the interaction of extremely low-frequency electromagnetic field (ELF/EMF) interactions with biological matter, and on the possibility that such interactions could have a harmful effect on human health. Journal articles and books are cited for the following topics: ELF/EMF theoretical interactions with biological cells, organs and organisms, magnetic dipole interactions, sensing by animals, biomedical-biophysical experiments, epidemiology, and litigation-mitigation risk issues.

  14. High school and college biology: A multi-level model of the effects of high school biology courses on student academic performance in introductory college biology courses

    Science.gov (United States)

    Loehr, John Francis

    The issue of student preparation for college study in science has been an ongoing concern for both college-bound students and educators of various levels. This study uses a national sample of college students enrolled in introductory biology courses to address the relationship between high school biology preparation and subsequent introductory college biology performance. Multi-Level Modeling was used to investigate the relationship between students' high school science and mathematics experiences and college biology performance. This analysis controls for student demographic and educational background factors along with factors associated with the college or university attended. The results indicated that high school course-taking and science instructional experiences have the largest impact on student achievement in the first introductory college biology course. In particular, enrollment in courses, such as high school Calculus and Advanced Placement (AP) Biology, along with biology course content that focuses on developing a deep understanding of the topics is found to be positively associated with student achievement in introductory college biology. On the other hand, experiencing high numbers of laboratory activities, demonstrations, and independent projects along with higher levels of laboratory freedom are associated with negative achievement. These findings are relevant to high school biology teachers, college students, their parents, and educators looking beyond the goal of high school graduation.

  15. Biological activities and health effects of terpenoids from marine fungi.

    Science.gov (United States)

    Kim, Se-Kwon; Li, Yong-Xin

    2012-01-01

    Recently, a great deal of interest has been developed by the consumers toward natural bioactive compounds as functional ingredients in the nutraceutical, cosmeceutical, and pharmaceutical products due to their various health beneficial effects. Hence, it can be suggested that bioactive functional ingredients from marine bioresources and their by-products are alternative sources for synthetic ingredients that can contribute to consumer's well-being, as a part of nutraceuticals and functional foods. Marine-derived fungi produce a vast array of secondary metabolites including terpenes, steroids, polyketides, peptides, alkaloids, and polysaccharides. These secondary metabolites serve many biopharmaceutical purposes. This chapter discusses about marine fungi-derived terpenoids and presents an overview of their beneficial health effects.

  16. Biological Effects of Nonionizing Electromagnetic Radiation. Volume V, Number 1.

    Science.gov (United States)

    1980-09-01

    7 Hz: field estimates were shorter than no-field killing fungi and retarding the fermentation of must. estimates. The differences were in the same...a photodiode detector association of t-caprolactam in cyclohexane. the The signal is processed and displayed as a digital association of n- butanol in... acetone effects c! Jirect current magnetic fields on E. coliare every second day) to induce skin cancer, and then much le..s than those reported by

  17. BIOLOGICAL EFFECTS OF TNF-BINDING VARIOLAVIRUS RECOMBINANT PROTEIN

    Directory of Open Access Journals (Sweden)

    I. A. Orlovskaya

    2012-01-01

    Full Text Available Abstract. This review presents a summary of our data concerning in vivo and in vitro effects of recombinant TNF-binding protein from variola virus (VARVCrmB upon TNF-induced functional changes of human and murine cells. VARV-CrmB protein blocks TNF-induced production of IL-1β and IL-6 by human mononuclear cells, and their in vitro oxidation-related metabolic (OM activity. VARV-CrmB protein restores TNF-induced reduction of BFU-E+CFU-E colony-forming activity and normalizes TNF-induced effects upon CFU-GM formation in a colony-forming model of human and murine bone morrow cells (BMC. VARV-CrmB protein displays a pronounced in vivo alleviation of LPS-induced endotoxic shock symptoms in SPF BALB/C mice thus significantly increasing survival of experimental animals. Moreover, VARV-CrmBprotein decreases intensity of collagen-induced arthritis at early terms. Application of VARV-CrmB protein results in normalization of TNF-induced increase of migratory and OM activity of murine leukocytes, and exerts corrective effects upon colony-forming ability of murine hematopoietic precursors. Skin application of VARV-CrmB protein decreases leukocyte migration from a skin scrap in afferent phase of DNCB-induced contact reaction, as well as “ear oedema” index. Our results demonstrate TNF-blocking properties of VARVCrmB protein. In summary, our data allow to consider a recombinant variola virus VARV-CrmB as a new potential TNF-antagonist. Its effects can be explained by its ability of neutralizing TNF-induced activation of oxidation-related metabolic, cytokine-producing and migratory functions of effector cells in therapy of pathological inflammatory processes.

  18. Biologic Effects of Dopamine on Tumor Vasculature in Ovarian Carcinoma

    Directory of Open Access Journals (Sweden)

    Myrthala Moreno-Smith

    2013-05-01

    Full Text Available Chronic sympathetic nervous system activation results in increased angiogenesis and tumor growth in orthotopic mouse models of ovarian carcinoma. However, the mechanistic effects of such activation on the tumor vasculature are not well understood. Dopamine (DA, an inhibitory catecholamine, regulates the functions of normal and abnormal blood vessels. Here, we examined whether DA, an inhibitory catecholamine, could block the effects of chronic stress on tumor vasculature and tumor growth. Exogenous administration of DA not only decreased tumor microvessel density but also increased pericyte coverage of tumor vessels following daily restraint stress in mice. Daily restraint stress resulted in significantly increased tumor growth in the SKOV3ip1 and HeyA8 ovarian cancer models. DA treatment blocked stress-mediated increases in tumor growth and increased pericyte coverage of tumor endothelial cells. Whereas the antiangiogenic effect of DA is mediated by dopamine receptor 2 (DR2, our data indicate that DA, through DR1, stimulates vessel stabilization by increasing pericyte recruitment to tumor endothelial cells. DA significantly stimulated migration of mouse 10T1/2 pericyte-like cells in vitro and increased cyclic adenosine mono-phosphate (cAMP levels in these cells. Moreover, DA or the DR1 agonist SKF 82958 increased platinum concentration in SKOV3ip1 tumor xenografts following cisplatin administration. In conclusion, DA stabilizes tumor blood vessels through activation of pericyte cAMP-protein kinase A signaling pathway by DR1. These findings could have implications for blocking the stimulatory effects of chronic stress on tumor growth.

  19. [Effects and Biological Response on Bioremediation of Petroleum Contaminated Soil].

    Science.gov (United States)

    Yang, Qian; Wu, Man-li; Nie, Mai-qian; Wang, Ting-ting; Zhang, Ming-hui

    2015-05-01

    Bioaugmentation and biostimulation were used to remediate petroleum-contaminated soil which were collected from Zichang city in North of Shaanxi. The optimal bioremediation method was obtained by determining the total petroleum hydrocarbon(TPH) using the infrared spectroscopy. During the bioremediation, number of degrading strains, TPH catabolic genes, and soil microbial community diversity were determined by Most Probable Number (MPN), polymerase chain reaction (PCR) combined agarose electrophoresis, and PCR-denaturing gradient electrophoresis (DGGE). The results in different treatments showed different biodegradation effects towards total petroleum hydrocarbon (TPH). Biostimulation by adding N and P to soils achieved the best degradation effects towards TPH, and the bioaugmentation was achieved by inoculating strain SZ-1 to soils. Further analysis indicated the positive correlation between catabolic genes and TPH removal efficiency. During the bioremediation, the number of TPH and alkanes degrading strains was higher than the number of aromatic degrading strains. The results of PCR-DGGE showed microbial inoculums could enhance microbial community functional diversity. These results contribute to understand the ecologically microbial effects during the bioremediation of petroleum-polluted soil.

  20. Biological Effects of Culture Substrates on Human Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Yohei Hayashi

    2016-01-01

    Full Text Available In recent years, as human pluripotent stem cells (hPSCs have been commonly cultured in feeder-free conditions, a number of cell culture substrates have been applied or developed. However, the functional roles of these substrates in maintaining hPSC self-renewal remain unclear. Here in this review, we summarize the types of these substrates and their effect on maintaining hPSC self-renewal. Endogenous extracellular matrix (ECM protein expression has been shown to be crucial in maintaining hPSC self-renewal. These ECM molecules interact with integrin cell-surface receptors and transmit their cellular signaling. We discuss the possible effect of integrin-mediated signaling pathways on maintaining hPSC self-renewal. Activation of integrin-linked kinase (ILK, which transmits ECM-integrin signaling to AKT (also known as protein kinase B, has been shown to be critical in maintaining hPSC self-renewal. Also, since naïve pluripotency has been widely recognized as an alternative pluripotent state of hPSCs, we discuss the possible effects of culture substrates and integrin signaling on naïve hPSCs based on the studies of mouse embryonic stem cells. Understanding the role of culture substrates in hPSC self-renewal and differentiation enables us to control hPSC behavior precisely and to establish scalable or microfabricated culture technologies for regenerative medicine and drug development.

  1. Radioactivity in the ocean: laws and biological effects

    Energy Technology Data Exchange (ETDEWEB)

    Hunsaker, C.T.

    1985-01-01

    This paper summarizes the literature on US laws and international agreements, experimental and monitoring data, and ongoing studies to provide background information for environmental assessment and regulatory compliance activities for ocean dumping of low-level radioactive waste. The Marine Protection, Research, and Sanctuaries Act is the major US legislation governing ocean disposal of radioactive waste. The major international agreement on ocean dumping is the Convention on the Prevention of Marine Pollution by Dumping of Wastes and other Matter. The United States ended its ocean dumping of radioactive wastes in 1970, but other countries have continued ocean dumping under international supervision in the northeast Atlantic. Monitoring of former US disposal sites has neither revealed significant effects on marine biota nor indicated a hazard to human health. Also, no effects on marine organisms have been found that could be attributed to routine discharges into the Irish Sea from the Windscale reprocessing plant. We must improve our ability to predict the oceanic carrying capacity and the fate and effects of ionizing radiation in the marine environment.

  2. Potential biological and ecological effects of flickering artificial light.

    Directory of Open Access Journals (Sweden)

    Richard Inger

    Full Text Available Organisms have evolved under stable natural lighting regimes, employing cues from these to govern key ecological processes. However, the extent and density of artificial lighting within the environment has increased recently, causing widespread alteration of these regimes. Indeed, night-time electric lighting is known significantly to disrupt phenology, behaviour, and reproductive success, and thence community composition and ecosystem functioning. Until now, most attention has focussed on effects of the occurrence, timing, and spectral composition of artificial lighting. Little considered is that many types of lamp do not produce a constant stream of light but a series of pulses. This flickering light has been shown to have detrimental effects in humans and other species. Whether a species is likely to be affected will largely be determined by its visual temporal resolution, measured as the critical fusion frequency. That is the frequency at which a series of light pulses are perceived as a constant stream. Here we use the largest collation to date of critical fusion frequencies, across a broad range of taxa, to demonstrate that a significant proportion of species can detect such flicker in widely used lamps. Flickering artificial light thus has marked potential to produce ecological effects that have not previously been considered.

  3. Therapeutic Effects of Microbubbles Added to Combined High-Intensity Focused Ultrasound and Chemotherapy in a Pancreatic Cancer Xenograft Model

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Mi Hye [Department of Radiology, Konkuk University Medical Center, Seoul 05030 (Korea, Republic of); Lee, Jae Young [Department of Radiology, Seoul National University Hospital, Seoul 03080 (Korea, Republic of); Kim, Hae Ri [Department of Pre-Dentistry, Gangneung-Wonju National University College of Dentistry, Gangneung 25457 (Korea, Republic of); Kim, Bo Ram; Park, Eun-Joo; Kim, Hoe Suk; Han, Joon Koo [Department of Radiology, Seoul National University Hospital, Seoul 03080 (Korea, Republic of); Choi, Byung Ihn [Department of Radiology, Chung-Ang University Hospital, Seoul 06973 (Korea, Republic of)

    2016-11-01

    To investigate whether high-intensity focused ultrasound (HIFU) combined with microbubbles enhances the therapeutic effects of chemotherapy. A pancreatic cancer xenograft model was established using BALB/c nude mice and luciferase-expressing human pancreatic cancer cells. Mice were randomly assigned to five groups according to treatment: control (n = 10), gemcitabine alone (GEM; n = 12), HIFU with microbubbles (HIFU + MB, n = 11), combined HIFU and gemcitabine (HIGEM; n = 12), and HIGEM + MB (n = 13). After three weekly treatments, apoptosis rates were evaluated using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay in two mice per group. Tumor volume and bioluminescence were monitored using high-resolution 3D ultrasound imaging and in vivo bioluminescence imaging for eight weeks in the remaining mice. The HIGEM + MB group showed significantly higher apoptosis rates than the other groups (p < 0.05) and exhibited the slowest tumor growth. From week 5, the tumor-volume-ratio relative to the baseline tumor volume was significantly lower in the HIGEM + MB group than in the control, GEM, and HIFU + MB groups (p < 0.05). Despite visible distinction, the HIGEM and HIGEM + MB groups showed no significant differences. High-intensity focused ultrasound combined with microbubbles enhances the therapeutic effects of gemcitabine chemotherapy in a pancreatic cancer xenograft model.

  4. Therapeutic effects of microbubble added to combined high-intensity focused ultrasound and chemotherapy in a pancreatic cancer xenograft model

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Mi Hye [Dept. of Radiology, Konkuk University Medical Center, Seoul (Korea, Republic of); Lee, Jae Young; Kim, Bo Ram; Park, Eun Joo; Kim, Hoe Suk; Han, Joon Koo [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); Kim, Hae Ri [Dept. of Pre-Dentistry, Gangneung-Wonju National University College of Dentistry, Gangneung (Korea, Republic of); Choi, Byung Ihn [Dept. of Radiology, Chung-Ang University Hospital, Seoul (Korea, Republic of)

    2016-09-15

    To investigate whether high-intensity focused ultrasound (HIFU) combined with microbubbles enhances the therapeutic effects of chemotherapy. A pancreatic cancer xenograft model was established using BALB/c nude mice and luciferase-expressing human pancreatic cancer cells. Mice were randomly assigned to five groups according to treatment: control (n = 10), gemcitabine alone (GEM; n = 12), HIFU with microbubbles (HIFU + MB, n = 11), combined HIFU and gemcitabine (HIGEM; n = 12), and HIGEM + MB (n = 13). After three weekly treatments, apoptosis rates were evaluated using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay in two mice per group. Tumor volume and bioluminescence were monitored using high-resolution 3D ultrasound imaging and in vivo bioluminescence imaging for eight weeks in the remaining mice. The HIGEM + MB group showed significantly higher apoptosis rates than the other groups (p < 0.05) and exhibited the slowest tumor growth. From week 5, the tumor-volume-ratio relative to the baseline tumor volume was significantly lower in the HIGEM + MB group than in the control, GEM, and HIFU + MB groups (p < 0.05). Despite visible distinction, the HIGEM and HIGEM + MB groups showed no significant differences. High-intensity focused ultrasound combined with microbubbles enhances the therapeutic effects of gemcitabine chemotherapy in a pancreatic cancer xenograft model.

  5. Neutron Exposures in Human Cells: Bystander Effect and Relative Biological Effectiveness

    Science.gov (United States)

    Seth, Isheeta; Schwartz, Jeffrey L.; Stewart, Robert D.; Emery, Robert; Joiner, Michael C.; Tucker, James D.

    2014-01-01

    Bystander effects have been observed repeatedly in mammalian cells following photon and alpha particle irradiation. However, few studies have been performed to investigate bystander effects arising from neutron irradiation. Here we asked whether neutrons also induce a bystander effect in two normal human lymphoblastoid cell lines. These cells were exposed to fast neutrons produced by targeting a near-monoenergetic 50.5 MeV proton beam at a Be target (17 MeV average neutron energy), and irradiated-cell conditioned media (ICCM) was transferred to unirradiated cells. The cytokinesis-block micronucleus assay was used to quantify genetic damage in radiation-naïve cells exposed to ICCM from cultures that received 0 (control), 0.5, 1, 1.5, 2, 3 or 4 Gy neutrons. Cells grown in ICCM from irradiated cells showed no significant increase in the frequencies of micronuclei or nucleoplasmic bridges compared to cells grown in ICCM from sham irradiated cells for either cell line. However, the neutron beam has a photon dose-contamination of 5%, which may modulate a neutron-induced bystander effect. To determine whether these low doses of contaminating photons can induce a bystander effect, cells were irradiated with cobalt-60 at doses equivalent to the percent contamination for each neutron dose. No significant increase in the frequencies of micronuclei or bridges was observed at these doses of photons for either cell line when cultured in ICCM. As expected, high doses of photons induced a clear bystander effect in both cell lines for micronuclei and bridges (pbystander effect in these cells. Finally, neutrons had a relative biological effectiveness of 2.0±0.13 for micronuclei and 5.8±2.9 for bridges compared to cobalt-60. These results may be relevant to radiation therapy with fast neutrons and for regulatory agencies setting standards for neutron radiation protection and safety. PMID:24896095

  6. Neutron exposures in human cells: bystander effect and relative biological effectiveness.

    Science.gov (United States)

    Seth, Isheeta; Schwartz, Jeffrey L; Stewart, Robert D; Emery, Robert; Joiner, Michael C; Tucker, James D

    2014-01-01

    Bystander effects have been observed repeatedly in mammalian cells following photon and alpha particle irradiation. However, few studies have been performed to investigate bystander effects arising from neutron irradiation. Here we asked whether neutrons also induce a bystander effect in two normal human lymphoblastoid cell lines. These cells were exposed to fast neutrons produced by targeting a near-monoenergetic 50.5 MeV proton beam at a Be target (17 MeV average neutron energy), and irradiated-cell conditioned media (ICCM) was transferred to unirradiated cells. The cytokinesis-block micronucleus assay was used to quantify genetic damage in radiation-naïve cells exposed to ICCM from cultures that received 0 (control), 0.5, 1, 1.5, 2, 3 or 4 Gy neutrons. Cells grown in ICCM from irradiated cells showed no significant increase in the frequencies of micronuclei or nucleoplasmic bridges compared to cells grown in ICCM from sham irradiated cells for either cell line. However, the neutron beam has a photon dose-contamination of 5%, which may modulate a neutron-induced bystander effect. To determine whether these low doses of contaminating photons can induce a bystander effect, cells were irradiated with cobalt-60 at doses equivalent to the percent contamination for each neutron dose. No significant increase in the frequencies of micronuclei or bridges was observed at these doses of photons for either cell line when cultured in ICCM. As expected, high doses of photons induced a clear bystander effect in both cell lines for micronuclei and bridges (pbystander effect in these cells. Finally, neutrons had a relative biological effectiveness of 2.0 ± 0.13 for micronuclei and 5.8 ± 2.9 for bridges compared to cobalt-60. These results may be relevant to radiation therapy with fast neutrons and for regulatory agencies setting standards for neutron radiation protection and safety.

  7. Biological effect of non-ionizing radiations on microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Kikuo; Yamamoto, Takayoshi [Osaka Univ., Radioisotope Research Center, Suita, Osaka (Japan); Nakaoka, Yasuo [Osaka Univ., Graduate School of Engineering Science, Department of Biophysical Engineering, Toyonaka, Osaka (Japan)

    2000-05-01

    We studied the effect of extremely low frequency magnetic fields (ELF-MF) of 60-Hz and 500 mT on the growth and the mutation frequency of the budding yeast S.cerevisiae and on the behavior of the ciliate Paramecium multimicronucleatum. The growth rate and mutation frequencies of several strains of S.cerevisiae (wild type and radiation sensitive mutants, rad or rev) were examined but no significant difference was observed. Moreover, the behavior of P.multimicronucleatum under the ELF-MF was examined. When exposed to a vertical field of 0.6 T, the cells accumulated at the upper end of the cuvette. (author)

  8. Behavioral and Biological Effects of Resonant Electromagnetic Absorption in Rats.

    Science.gov (United States)

    1976-11-01

    C) -c C) C) C) tj~ C) C) -c C -C C C’: k ~ ~f jt~ - 39 - anesthetized wits Nembuta] 𔃿 mg/kg). !he LCOF temperature probe1 0 " ] a,, 7 : t. ’on.. enI...Animals with and wit ,.hout Ground Effects", to be submitted for publication to IEEEr Trcznsac -ions or IMior’clave Theory and T,,chriques. 2. 0. P. G... B17 ... .- .- 20 Value for various regions of the leg * aValue for various regions of the arm 10 Ci a U 6 *\\ , c0 0.3 0.6 0.9 1.5 3.0 2 Cross

  9. Effect of biologic therapy on radiological progression in rheumatoid arthritis: what does it add to methotrexate?

    Directory of Open Access Journals (Sweden)

    Jones G

    2012-07-01

    Full Text Available Graeme Jones, Erica Darian-Smith, Michael Kwok, Tania WinzenbergMenzies Research Institute, University of Tasmania, Tasmania, AustraliaAbstract: There have been substantial advances in the treatment of rheumatoid arthritis in recent years. Traditional disease-modifying antirheumatic drugs (DMARDs have been shown to have small effects on the progression of radiographic damage. This quantitative overview summarizes the evidence for biologic DMARDS and radiographic damage either alone or in combination with methotrexate. Two outcomes were used (standardized mean difference and odds of progression. A total of 21 trials were identified of which 18 had useable data. For biologic monotherapy, tocilizumab, adalimumab, and etanercept were significantly better than methotrexate, with tocilizumab ranking first in both outcomes while golimumab was ineffective in both outcomes. For a biologic in combination with methotrexate compared with methotrexate alone, most therapies studied (etanercept, adalimumab, infliximab, certolizumab, tocilizumab, and rituximab were effective at slowing X-ray progression using either outcome, with infliximab ranking first in both outcomes. The exceptions to this were golimumab (no effect on standardized mean difference and abatacept (no effect on odds of progression. This effect was additional to methotrexate; thus, the overall benefit is moderate to large in magnitude, which is clearly of major clinical significance for sufferers of rheumatoid arthritis and supports the use of biologic DMARDs in those with a poor disease prognosis.Keywords: rheumatoid, trials, meta-analysis, radiographs, biologic, disease-modifying antirheumatic drugs, DMARDs

  10. EFFECTS OF 5E LEARNING CYCLE ON STUDENTS ACHIEVEMENT IN BIOLOGY AND CHEMISTRY

    Directory of Open Access Journals (Sweden)

    Patrick Osawaru Ajaja,

    2012-01-01

    Full Text Available The major purpose of this study was to determine the effects of learning cycle as an instructional strategy on biology andchemistry students achievement. To guide this study, six research hypotheses were stated and tested at 0.05 level ofsignificance. The design of this study was 2x2x3x6 Pre-test Post-test non-equivalent control group quasi experimental design.These included two instructional groups (experimental and control groups, sex (male and female, repeated testing (Pre,Post and follow-up tests, and six weeks of experience. The samples of the study included six senior secondary schools, 112science students, and 12 biology and chemistry teachers. The instruments used for this study were: teacher’s questionnaireon knowledge and use of learning cycle (KULC; and Biology and Chemistry Achievement Test (BCAT. The data collected wereanalyzed with simple percentage, Analysis of Covariance (ANCOVA and student t-test statistics. The major findings of thestudy included that only 30.43% and 26.31% of biology and chemistry teachers have the knowledge that learning cycle is aninstructional method; all the biology and chemistry teachers sampled have never used learning cycle as an instructionalmethod; learning cycle had a significant effect on students achievement in biology and chemistry; students taught withlearning cycle significantly achieved better in biology/chemistry Post-test than those taught with lecture method; the posttestscores of students in the learning cycle group increased over the period of experience; non-significant difference in Posttestscores between males and females taught with learning cycle; non-significant interaction effect between method andsex on achievement; and a significant higher retention of biology and chemistry knowledge by students taught with learningcycle than those taught with lecture method. It was concluded that the method seems an appropriate instructional modelthat could be used to solve the problems of

  11. Catalytically and noncatalytically treated automobile exhaust: biological effects in rats

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, G.P. (Univ. of Cincinnati); Lewkowski, J.P.; Hastings, L.; Malanchuk, M.

    1977-12-01

    Chronic exposure to catalytically treated or noncatalytically treated automobile exhaust significantly depressed the spontaneous locomotor activity (SLA) of rats. Exposure to H/sub 2/SO/sub 4/ alone or CO at comparable levels did not alter the SLA. Exposure to noncatalytically treated exhaust resulted in significant reductions in growth rate and food and water intake. However, these effects were not evident in the exposure to catalytically treated exhaust or in the control H/sub 2/SO/sub 4/ and CO exposures. Blood acid-base analyses indicated that exposure to either catalytically treated exhaust or H/sub 2/SO/sub 4/ elicits a metabolic alkalosis, while exposure to CO alone results in a metabolic acidosis. All acid-base parameters were within the normal range several weeks after the termination of exposure.

  12. Oil spills: Biological effects. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    The bibliography contains citations concerning the biological and ecological effects of oil spills. Citations discuss effects on microorganisms, plants, and animals. Damage assessment, ecological modeling, and environmental impact statements are included. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  13. Low power laser therapy — an introduction and a review of some biological effects

    OpenAIRE

    Thiel, Haymo

    1986-01-01

    This report gives a brief introduction to the characteristics of therapeutic low power laser devices. Absorption, tissue penetration and physiological mechanisms of laser irradiation are discussed. The biological effects of low power laser light are reviewed in the areas of collagen metabolism, woundhealing, inflammation and pain control. Contraindications, precautions and side effects of low power laser irradiation are discussed.

  14. Biological effect markers for exposure to carcinogenic compound and their relevance for risk assessment

    NARCIS (Netherlands)

    Delft, J.H.M. van; Baan, R.A.; Roza, L.

    1998-01-01

    In this review data are summarized on biomarkers that are used for biological effect monitoring of human populations exposed to genotoxic carcinogens. The biomarkers are DNA and protein adducts and cytogenetic effects. Most of these biomarkers are relevant for the process of carcinogenesis. Emphasis

  15. The First Time Ever I Saw Your Feet: Inversion Effect in Newborns' Sensitivity to Biological Motion

    Science.gov (United States)

    Bardi, Lara; Regolin, Lucia; Simion, Francesca

    2014-01-01

    Inversion effect in biological motion perception has been recently attributed to an innate sensitivity of the visual system to the gravity-dependent dynamic of the motion. However, the specific cues that determine the inversion effect in naïve subjects were never investigated. In the present study, we have assessed the contribution of the local…

  16. [Adipogenic function and other biologic effects of insulin].

    Science.gov (United States)

    Pankov, Y A

    2016-01-01

    Studies on experimental animals with knockout of the insulin receptor gene Insr (in the whole body or in certain tissues) and/or related genes encoding proteins involved in realization of insulin signal transduction in target cells, have made an important contribution to the elucidation of insulin regulation of metabolism, particularly fat metabolism. Since the whole insulin secreted by b-cells, together with the products of gastrointestinal tract digestion of proteins, fats, and carbohydrates reach the liver, the latter is the first organ on which this hormone acts. The liver employs released amino acids for synthesis of proteins, including apoproteins for various lipoproteins. Glucose is used for synthesis of glycogen, fatty acids, and triglycerides, which enter all the organs in very low density lipoproteins (VLDL). The LIRKO mice with knockout of the Insr gene in the liver demonstrated inhibition of synthesis of macromolecular compounds from amino acids, glucose, and fatty acids. Low molecular weight substances demonstrated increased entry to circulation, and together with other disorders induced hyperglycemia. In LIRKO mice blood glucose levels and glucose tolerance demonstrated time-dependent normalization and at later stages the increase in glucose levels was replaced by hypoglycemia. These changes can be well explained if we take into consideration that one of the main functions of insulin consists in stimulation of energy accumulation by means of activation of triglyceride deposition in adipose tissue. FIRKO mice with selective knockout of adipose tissue Insr were characterized by decreased uptake of glucose in adipocytes, and its transformation into lipids. However, the level of body fat in animals remained normal, possibly due to preserved insulin receptor in the liver and insulin-induced activation of triglyceride production which maintained normal levels of body fat stores, the effective functioning of adipose tissue and secretion of leptin by

  17. [Quality of interior air: biological contaminants and their effects on health; bioaerosols and gathering techniques].

    Science.gov (United States)

    Bălan, Gabriela

    2007-01-01

    Indoor Air Quality: biological contaminants and health effects; airborne organisms and sampling instruments. Biological contaminants include bacteria, molds, viruses, animal dander and cat saliva, house dust, mites, cockroaches and pollen. Symptoms of health problems caused by biological pollutants include sneezing, watery eyes, coughing, shortness of breath, dizziness, lethargy, fevers. Children, elderly people with breathing problems, allergies and lung diseases are particularly susceptible to disease-causing biological agents in the indoor air. It is convenient to consider microbiological samplers for collecting organisms in air as falling into several broad categories. Many popular microbiological air samplers use the principle of impaction to trap the organisms by impacting them directly on to agar. Further distinct groups are the impingers, which operate by impinging organisms into liquid.

  18. Biologic effects of fenbendazole in rats and mice: a review.

    Science.gov (United States)

    Villar, David; Cray, Carolyn; Zaias, Julia; Altman, Norman H

    2007-11-01

    This review summarizes findings from toxicologic, carcinogenic, immunologic, and metabolic studies on fenbendazole (FBZ). Currently, FBZ is used to treat or prevent pinworm outbreaks in laboratory rodents. Because antiparasitic treatments usually are not part of experimental designs, interactions from the medication on the outcomes of ongoing experiments are a concern. At therapeutic levels, FBZ does not alter the total content of cytochromes P450 but does induce certain hepatic cytochrome P450 isoforms, namely 1A1, 1A2, and 2B1. Although expressed constitutively at low or undetectable levels, these isoforms particularly are known for bioactivating a number of procarcinogens. Lifetime studies in rats have shown that FBZ is not a carcinogen but that it may behave as a tumor promoter when given after certain initiators. Unlike in other animal species, FBZ treatment-associated myelosuppression has not been reported to occur in rodents. The few currently available immunologic studies in mice, including an autoimmune model, have not shown effects on selected immune responses. However, data from other animal species suggest that the ability of B and T lymphocytes to proliferate in the secondary immune response may be suppressed during treatment with FBZ.

  19. Bioaccumulation and biological effects of cigarette litter in marine worms

    Science.gov (United States)

    Wright, Stephanie L.; Rowe, Darren; Reid, Malcolm J.; Thomas, Kevin V.; Galloway, Tamara S.

    2015-01-01

    Marine debris is a global environmental issue. Smoked cigarette filters are the predominant coastal litter item; 4.5 trillion are littered annually, presenting a source of bioplastic microfibres (cellulose acetate) and harmful toxicants to marine environments. Despite the human health risks associated with smoking, little is known of the hazards cigarette filters present to marine life. Here we studied the impacts of smoked cigarette filter toxicants and microfibres on the polychaete worm Hediste diversicolor (ragworm), a widespread inhabitant of coastal sediments. Ragworms exposed to smoked cigarette filter toxicants in seawater at concentrations 60 fold lower than those reported for urban run-off exhibited significantly longer burrowing times, >30% weight loss, and >2-fold increase in DNA damage compared to ragworms maintained in control conditions. In contrast, ragworms exposed to smoked cigarette filter microfibres in marine sediment showed no significant effects. Bioconcentration factors for nicotine were 500 fold higher from seawater than from sediment. Our results illustrate the vulnerability of organisms in the water column to smoking debris and associated toxicants, and highlight the risks posed by smoked cigarette filter debris to aquatic life. PMID:26369692

  20. Biological effects of exposure to intermediate neutron and repair mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Utsumi, Hiroshi; Sasaki, Masao [Kyoto Univ. (Japan); Onishi, Takeo; Onizuka, Masahiko

    2000-01-01

    An investigation was made on cytotoxic effects of neutron capture using chicken B-cell line mutants, DT40, KURO{sup -/-}, RAD54 {sup -/-} and KU70{sup -/-} / RAD54{sup -/-}. Suspensions of these cells were exposed to two times X-radiation at various doses and the cell surviving was evaluated. The sensitivity to radiation was highest in the double defective mutant, KU70{sup -/-} / RAD54{sup -/-} and followed by that of RAD54 {sup -/-}, a homologous recombination mutant, whereas KURO {sup -/-} cell, a non-homologous end-joining mutant showed a peculiar surviving curve composed of two phases and the cell was highly sensitive to a low-dose radiation. This indicates that there are two different DNA repair systems for double-strand breaks and the system for non-homologous end-joining repair can be involved in all phases of cell cycle, but the system for the homologous one is involved only in S-phase. Therefore, it was thought that variation of sensitivity to radiation exposure depending to the phase of cell cycle might explain the alternation of repair system depending to the phase progressing of cell cycle. It was thus likely that the recovery from radiation injury, which is still a black box might be explained with the double strand breaks of DNA. (M.N.)

  1. The biological effect and medical functions of the Infrared Rays

    Institute of Scientific and Technical Information of China (English)

    PANG Xiao-feng

    2001-01-01

    The quantum vibrational energy-spectra including high excited states of the protein molecules have been calculated by new theory of bio-energy transport along the protein molecules and its dynamic equation, discrete nonlinear Schrodinger equation, appropriate to the protein molecules on the basis of the level of molecular structure. This energy-spectra obtained are basically consistent with the experimental values by infrared absorption and radiated measurement of person's hands and laser-Raman spectrum from metabolically active E. Coli.. From this energy-spectra we know that the infrared lights with (1-3)x1000nm and (5-7)x1000nm wavelength can be absorbed by the protein molecules in the living systems.In accordance with the non-linear theory of the bio-energy transport we know that the energy of the infrared light absorbed by the proteins can result in vibrations of amide-I in amino acids and can facilitate the bio-energy transport along the protein molecular chains from one place to other for the growth of living bodies. This processe is non-thermal. This is just non-thermal effect of the infrared lights. According to the mechanism we explained further the medical functions of the infrared lights absorbed.

  2. Cardiometabolic risk in psoriasis: differential effects of biologic agents

    Directory of Open Access Journals (Sweden)

    Mariana J Kaplan

    2008-12-01

    Full Text Available Mariana J KaplanDepartment of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USAAbstract: Psoriasis is associated to an increased risk of cardiovascular (CV complications. Overall, the pathogenic mechanisms involved in premature CV complications in psoriasis appear to be complex and multifactorial, with traditional and nontraditional risk factors possibly contributing to the increased risk. Based on what is known about the pathogenesis of psoriasis and extrapolating the current knowledge on CV complications in other inflammatory diseases, studies are needed to investigate if appropriate control of the inflammatory, immunologic and metabolic disturbances present in psoriasis can prevent the development of this potentially lethal complication. It is clear that there is a great need for heightened awareness of the increased risk for vascular damage in patients with psoriasis. It is also crucial to closely monitor patients with psoriasis for CV risk factors including obesity, hypertension, diabetes, and hyperlipidemia. Whether treatment regimens that effectively manage systemic inflammation will lead to prevention of CV complications in psoriasis needs to be investigated. Clearly, studies should focus on establishing the exact mechanisms that determine CV risk in psoriasis so that appropriate preventive strategies and treatment guidelines can be established.Keywords: psoriasis, atherosclerosis, inflammation, vascular

  3. Effects of Magnetic Field on Biological Cells and Applications

    Science.gov (United States)

    Chen, Ching-Jen

    2001-03-01

    While there has been extensive research performed in the physics of magnetic fields and the physics and chemistry in life sciences, independent of each other, there has been a paucity of scientific research and development investigating the possible applications of magnetic fields in life sciences. The focus of this presentation is to present the stimulation mechanism by which magnetic fields affect (a) yeast cells (b) plant cells and (c) mammalian normal and cancer cells. Recently we have found that the Saccharomyces Cerevsa yeast growth increases by about 30to a 1 tesla field and the production of CO2 increases by about 30of yeast metabolism may be due to an increase in intercellular interaction and protein channel alignment, the introduction of an alteration in the DNA from the magnetic field exposure or a combination of these mechanisms. We also have found that the application of high magnetic fields (1 tesla and above) can have marked effects on the germination and growth of plants, especially corn, beans and peas. This finding has opened up the possibility of technology developments in botanical growth systems to accelerate seed germination and crop harvesting. Most recently we have investigated the application of high magnetic fields on leukemia, CaCoII and HEP G2 cancer cell lines. We found that when leukemia are exposed to a 12 tesla field for 2 hours has an increase in cell death by about 30that were not exposed to the magnetic field. Viability of CaCoII cells sandwiched between permanent magnets of maximum strength of 1.2 tesla was measured. A decrease in viable cells by 33unexposed cells. HSP 70 was measured for HEPG2 cells that were exposed to permanent magnetic field of 1.2 tesla for 40 minutes and for unexposed cells. It was found that the exposed cells produce 19 times more HSP70 compared to unexposed cells. Our results together with other investigators report suggest a strong evidence of a reduction in the cell growth rate for cancer cells when

  4. Noninvasive MR-Guided HIFU Therapy of TSC-Associated Renal Angiomyolipomas

    Science.gov (United States)

    2014-09-01

    schematic design of the "double" shear mode ME sensor, the polling of piezo layer (PVDF) is in the -x direction and the magnetization of the magnetoelastic...that the shear mode piezo -magnetic constant d15 is much larger than d33 and d31, while the piezo -charge constant is a little smaller than d33 but...sensor project. Fig.1 Schematic representation of the ME effect in the composites utilizing the product property 12 Piezo

  5. Allee effects in tritrophic food chains: some insights in pest biological control.

    Science.gov (United States)

    Costa, Michel Iskin da S; Dos Anjos, Lucas

    2016-12-01

    Release of natural enemies to control pest populations is a common strategy in biological control. However, its effectiveness is supposed to be impaired, among other factors, by Allee effects in the biological control agent and by the fact that introduced pest natural enemies interact with some native species of the ecosystem. In this work, we devise a tritrophic food chain model where the assumptions previously raised are proved correct when a hyperpredator attacks the introduced pest natural enemy by a functional response type 2 or 3. Moreover, success of pest control is shown to be related to the release of large amounts (i.e., inundative releases) of natural enemies.

  6. Temperature elevation by HIFU in ex vivo porcine muscle: MRI measurement and simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Solovchuk, Maxim A., E-mail: solovchuk@gmail.com [Center for Advanced Study in Theoretical Sciences (CASTS), National Taiwan University, Taipei 10617, Taiwan (China); Hwang, San Chao; Chang, Hsu [Medical Engineering Research Division, National Health Research Institute, Miaoli 35053, Taiwan (China); Thiriet, Marc [Sorbonne Universités, UPMC Univ Paris 06, UMR 7598, Laboratoire Jacques-Louis Lions, F-75005, Paris (France); Sheu, Tony W. H., E-mail: twhsheu@ntu.edu.tw [Department of Engineering Science and Ocean Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan, Republic of China and Center for Advanced Study in Theoretical Sciences (CASTS), National Taiwan University, Taipei 10617, Taiwan (China)

    2014-05-15

    Purpose: High-intensity focused ultrasound is a rapidly developing medical technology with a large number of potential clinical applications. Computational model can play a pivotal role in the planning and optimization of the treatment based on the patient's image. Nonlinear propagation effects can significantly affect the temperature elevation and should be taken into account. In order to investigate the importance of nonlinear propagation effects, nonlinear Westervelt equation was solved. Weak nonlinear propagation effects were studied. The purpose of this study was to investigate the correlation between the predicted and measured temperature elevations and lesion in a porcine muscle. Methods: The investigated single-element transducer has a focal length of 12 cm, an aperture of 8 cm, and frequency of 1.08 MHz. Porcine muscle was heated for 30 s by focused ultrasound transducer with an acoustic power in the range of 24–56 W. The theoretical model consists of nonlinear Westervelt equation with relaxation effects being taken into account and Pennes bioheat equation. Results: Excellent agreement between the measured and simulated temperature rises was found. For peak temperatures above 85–90 °C “preboiling” or cavitation activity appears and lesion distortion starts, causing small discrepancy between the measured and simulated temperature rises. From the measurements and simulations, it was shown that distortion of the lesion was caused by the “preboiling” activity. Conclusions: The present study demonstrated that for peak temperatures below 85–90 °C numerical simulation results are in excellent agreement with the experimental data in three dimensions. Both temperature rise and lesion size can be well predicted. Due to nonlinear effect the temperature in the focal region can be increased compared with the linear case. The current magnetic resonance imaging (MRI) resolution is not sufficient. Due to the inevitable averaging the measured

  7. Study of complex matrix effect on solid phase microextraction for biological sample analysis.

    Science.gov (United States)

    Jiang, Ruifen; Xu, Jianqiao; Zhu, Fang; Luan, Tiangang; Zeng, Feng; Shen, Yong; Ouyang, Gangfeng

    2015-09-11

    Solid phase microextraction (SPME) has become a useful tool for in vivo monitoring the behavior of environmental organic pollutants in biological species due to its simplicity, relatively non-invasive, and cost-effective manner. However, the complex matrices in biological samples could significantly influence the extraction kinetic, and bias the quantification result. In this study, we investigated the effect of complex matrix on the extraction kinetic of SPME for biological sample analysis. Two sample matrices, phosphate-buffered saline (PBS) with bovine serum albumin (BSA) and agarose gel with BSA were used to simulate the biological fluid and tissue. Results showed that the addition of BSA significantly enhanced the mass transfer of organic compounds onto SPME fiber in both PBS buffer and gel sample. Enhancement factors ranging from 1.3 to 27, and 2.0 to 80 were found for all selected polyaromatic hydrocarbons (PAHs) in PBS buffer and agarose gel with BSA concentration of 0.1-5%, respectively. Then, an improved theoretical model was applied to quantify the observed enhancement effect, and the result showed that the predicted sampling time constant agreed well with the experimental one in complex matrix. Furthermore, a simplified equation was proposed for the real biological sample analysis.

  8. Nonlinear effects of the finite amplitude ultrasound wave in biological tissues

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Nonlinear effects will occur during the transmission of the finite amplitude wave in biological tissues.The theoretical prediction and experimental demonstration of the nonlinear effects on the propagation of the finite amplitude wave at the range of biomedical ultrasound frequency and intensity are studied.Results show that the efficiency factor and effective propagation distance will decrease while the attenuation coefficient increases due to the existence of nonlinear effects.The experimental results coincided quite well with the theory.This shows that the effective propagation distance and efficiency factor can be used to describe quantitatively the influence of nonlinear effects on the propagation of the finite amplitude sound wave in biological tissues.

  9. ICBEN review of research on the biological effects of noise 2011-2014.

    Science.gov (United States)

    Basner, Mathias; Brink, Mark; Bristow, Abigail; de Kluizenaar, Yvonne; Finegold, Lawrence; Hong, Jiyoung; Janssen, Sabine A; Klaeboe, Ronny; Leroux, Tony; Liebl, Andreas; Matsui, Toshihito; Schwela, Dieter; Sliwinska-Kowalska, Mariola; Sörqvist, Patrik

    2015-01-01

    The mandate of the International Commission on Biological Effects of Noise (ICBEN) is to promote a high level of scientific research concerning all aspects of noise-induced effects on human beings and animals. In this review, ICBEN team chairs and co-chairs summarize relevant findings, publications, developments, and policies related to the biological effects of noise, with a focus on the period 2011-2014 and for the following topics: Noise-induced hearing loss; nonauditory effects of noise; effects of noise on performance and behavior; effects of noise on sleep; community response to noise; and interactions with other agents and contextual factors. Occupational settings and transport have been identified as the most prominent sources of noise that affect health. These reviews demonstrate that noise is a prevalent and often underestimated threat for both auditory and nonauditory health and that strategies for the prevention of noise and its associated negative health consequences are needed to promote public health.

  10. Effective identification of conserved pathways in biological networks using hidden Markov models.

    Directory of Open Access Journals (Sweden)

    Xiaoning Qian

    Full Text Available BACKGROUND: The advent of various high-throughput experimental techniques for measuring molecular interactions has enabled the systematic study of biological interactions on a global scale. Since biological processes are carried out by elaborate collaborations of numerous molecules that give rise to a complex network of molecular interactions, comparative analysis of these biological networks can bring important insights into the functional organization and regulatory mechanisms of biological systems. METHODOLOGY/PRINCIPAL FINDINGS: In this paper, we present an effective framework for identifying common interaction patterns in the biological networks of different organisms based on hidden Markov models (HMMs. Given two or more networks, our method efficiently finds the top matching paths in the respective networks, where the matching paths may contain a flexible number of consecutive insertions and deletions. CONCLUSIONS/SIGNIFICANCE: Based on several protein-protein interaction (PPI networks obtained from the Database of Interacting Proteins (DIP and other public databases, we demonstrate that our method is able to detect biologically significant pathways that are conserved across different organisms. Our algorithm has a polynomial complexity that grows linearly with the size of the aligned paths. This enables the search for very long paths with more than 10 nodes within a few minutes on a desktop computer. The software program that implements this algorithm is available upon request from the authors.

  11. Waist circumference as a mediator of biological maturation effect on the motor coordination in children

    Directory of Open Access Journals (Sweden)

    Leonardo G.O. Luz

    Full Text Available Abstract Objective: The present study aimed to: 1 examine the association of biological maturation effect on performance at a motor coordination battery and 2 to assess whether the association between biological maturation and scores obtained in motor coordination tests is mediated by some anthropometric measurement. Methods: The convenience sample consisted of 73 male children aged 8 years old. Anthropometric data considered the height, body mass, sitting height, waist circumference, body mass index, fat mass and fat-free mass estimates. Biological maturation was assessed by the percentage of the predicted mature stature. Motor coordination was tested by the Körperkoordinationstest für Kinder. A partial correlation between anthropometric measurements, z-score of maturation and the motor coordination tests were performed, controlling for chronological age. Finally, causal mediation analysis was performed. Results: Height, body mass, waist circumference and fat mass showed a slight to moderate inverse correlation with motor coordination. Biological maturation was significantly associated with the balance test with backward walking (r=-0.34. Total mediation of the waist circumference was identified in the association between biological maturation and balance test with backward walking (77%. Conclusions: We identified an association between biological maturation and KTK test performance in male children and also verified that there is mediation of waist circumference. It is recommended that studies be carried out with female individuals and at other age ranges.

  12. A Study Assessing the Potential of Negative Effects in Interdisciplinary Math–Biology Instruction

    Science.gov (United States)

    Madlung, Andreas; Bremer, Martina; Himelblau, Edward; Tullis, Alexa

    2011-01-01

    There is increasing enthusiasm for teaching approaches that combine mathematics and biology. The call for integrating more quantitative work in biology education has led to new teaching tools that improve quantitative skills. Little is known, however, about whether increasing interdisciplinary work can lead to adverse effects, such as the development of broader but shallower skills or the possibility that math anxiety causes some students to disengage in the classroom, or, paradoxically, to focus so much on the mathematics that they lose sight of its application for the biological concepts in the center of the unit at hand. We have developed and assessed an integrative learning module and found disciplinary learning gains to be equally strong in first-year students who actively engaged in embedded quantitative calculations as in those students who were merely presented with quantitative data in the context of interpreting biological and biostatistical results. When presented to advanced biology students, our quantitative learning tool increased test performance significantly. We conclude from our study that the addition of mathematical calculations to the first year and advanced biology curricula did not hinder overall student learning, and may increase disciplinary learning and data interpretation skills in advanced students. PMID:21364099

  13. Waist circumference as a mediator of biological maturation effect on the motor coordination in children

    Science.gov (United States)

    Luz, Leonardo G.O.; Seabra, André; Padez, Cristina; Duarte, João P.; Rebelo-Gonçalves, Ricardo; Valente-dos-Santos, João; Luz, Tatiana D.D.; Carmo, Bruno C.M.; Coelho-e-Silva, Manuel

    2016-01-01

    Abstract Objective: The present study aimed to: 1) examine the association of biological maturation effect on performance at a motor coordination battery and 2) to assess whether the association between biological maturation and scores obtained in motor coordination tests is mediated by some anthropometric measurement. Methods: The convenience sample consisted of 73 male children aged 8 years old. Anthropometric data considered the height, body mass, sitting height, waist circumference, body mass index, fat mass and fat-free mass estimates. Biological maturation was assessed by the percentage of the predicted mature stature. Motor coordination was tested by the Körperkoordinationstest für Kinder. A partial correlation between anthropometric measurements, z-score of maturation and the motor coordination tests were performed, controlling for chronological age. Finally, causal mediation analysis was performed. Results: Height, body mass, waist circumference and fat mass showed a slight to moderate inverse correlation with motor coordination. Biological maturation was significantly associated with the balance test with backward walking (r=-0.34). Total mediation of the waist circumference was identified in the association between biological maturation and balance test with backward walking (77%). Conclusions: We identified an association between biological maturation and KTK test performance in male children and also verified that there is mediation of waist circumference. It is recommended that studies be carried out with female individuals and at other age ranges. PMID:26972616

  14. Waist circumference as a mediator of biological maturation effect on the motor coordination in children.

    Science.gov (United States)

    Luz, Leonardo G O; Seabra, André; Padez, Cristina; Duarte, João P; Rebelo-Gonçalves, Ricardo; Valente-Dos-Santos, João; Luz, Tatiana D D; Carmo, Bruno C M; Coelho-E-Silva, Manuel

    2016-09-01

    The present study aimed to: 1) examine the association of biological maturation effect on children's performance at a motor coordination battery and 2) to assess whether the association between biological maturation and scores obtained in motor coordination tests is mediated by some anthropometric measurement. The convenience sample consisted of 73 male children aged 8 years old. Anthropometric data considered the height, body mass, sitting height, waist circumference, body mass index, fat mass and fat-free mass estimates. Biological maturation was assessed by the percentage of the predicted mature stature. Motor coordination was tested by the Körperkoordinationstest für Kinder. A partial correlation between anthropometric measurements, z-score of maturation and the motor coordination tests were performed, controlling for chronological age. Finally, causal mediation analysis was performed. Height, body mass, waist circumference and fat mass showed a slight to moderate inverse correlation with motor coordination. Biological maturation was significantly associated with the balance test with backward walking (r=-0.34). Total mediation of the waist circumference was identified in the association between biological maturation and balance test with backward walking (77%). We identified an association between biological maturation and KTK test performance in male children and also verified that there is mediation of waist circumference. It is recommended that studies be carried out with female individuals and at other age ranges. Copyright © 2016 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

  15. Modeling prostate anatomy from multiple view TRUS images for image-guided HIFU therapy.

    Science.gov (United States)

    Penna, Michael A; Dines, Kris A; Seip, Ralf; Carlson, Roy F; Sanghvi, Narendra T

    2007-01-01

    Current planning methods for transrectal high-intensity focused ultrasound treatment of prostate cancer rely on manually defining treatment regions in 15-20 sector transrectal ultrasound (TRUS) images of the prostate. Although effective, it is desirable to reduce user interaction time by identifying functionally related anatomic structures (segmenting), then automatically laying out treatment sites using these structures as a guide. Accordingly, a method has been developed to effectively generate solid three-dimensional (3-D) models of the prostate, urethra, and rectal wall from boundary trace data. Modeling the urethra and rectal wall are straightforward, but modeling the prostate is more difficult and has received much attention in the literature. New results presented here are aimed at overcoming many of the limitations of previous approaches to modeling the prostate while using boundary traces obtained via manual tracing in as few as 5 sector and 3 linear images. The results presented here are based on a new type of surface, the Fourier ellipsoid, and the use of sector and linear TRUS images. Tissue-specific 3-D models will ultimately permit finer control of energy deposition and more selective destruction of cancerous regions while sparing critical neighboring structures.

  16. Neutron exposures in human cells: bystander effect and relative biological effectiveness.

    Directory of Open Access Journals (Sweden)

    Isheeta Seth

    Full Text Available Bystander effects have been observed repeatedly in mammalian cells following photon and alpha particle irradiation. However, few studies have been performed to investigate bystander effects arising from neutron irradiation. Here we asked whether neutrons also induce a bystander effect in two normal human lymphoblastoid cell lines. These cells were exposed to fast neutrons produced by targeting a near-monoenergetic 50.5 MeV proton beam at a Be target (17 MeV average neutron energy, and irradiated-cell conditioned media (ICCM was transferred to unirradiated cells. The cytokinesis-block micronucleus assay was used to quantify genetic damage in radiation-naïve cells exposed to ICCM from cultures that received 0 (control, 0.5, 1, 1.5, 2, 3 or 4 Gy neutrons. Cells grown in ICCM from irradiated cells showed no significant increase in the frequencies of micronuclei or nucleoplasmic bridges compared to cells grown in ICCM from sham irradiated cells for either cell line. However, the neutron beam has a photon dose-contamination of 5%, which may modulate a neutron-induced bystander effect. To determine whether these low doses of contaminating photons can induce a bystander effect, cells were irradiated with cobalt-60 at doses equivalent to the percent contamination for each neutron dose. No significant increase in the frequencies of micronuclei or bridges was observed at these doses of photons for either cell line when cultured in ICCM. As expected, high doses of photons induced a clear bystander effect in both cell lines for micronuclei and bridges (p<0.0001. These data indicate that neutrons do not induce a bystander effect in these cells. Finally, neutrons had a relative biological effectiveness of 2.0 ± 0.13 for micronuclei and 5.8 ± 2.9 for bridges compared to cobalt-60. These results may be relevant to radiation therapy with fast neutrons and for regulatory agencies setting standards for neutron radiation protection and safety.

  17. Methods for studying and criteria for evaluating the biological effects of electric fields of industrial frequency

    Energy Technology Data Exchange (ETDEWEB)

    Savin, B.M.; Shandala, M.G.; Nikonova, K.V.; Morozov, Yu.A.

    1978-10-01

    Data are reviewed from a number of USSR research studies on the biological effects of electric power transmission lines of 1150 Kv and above. Effects on man, plants, animals, and terrestrial ecosystems are reported. Existing health standards in the USSR for the exposure of personnel working in electric fields are included. It is concluded that high-voltage electric fields have a harmful effect on man and his environment.

  18. Design of a HIFU array for the treatment of deep venous thrombosis: a simulation study

    Science.gov (United States)

    Smirnov, Petr; Hynynen, Kullervo

    2017-08-01

    Deep venous thrombosis of the iliofemoral veins is a common and morbid disease, with the recommended interventional treatment carrying a high risk of hemorrhaging and complications. High intensity focused ultrasound delivered with a single element transducer has been shown to successfully precipitate thrombolysis non-invasively in vitro and in vivo. However, in all previous studies damage to the veins or surrounding tissue has been observed. Using a simulation model of the human thigh, this study investigated whether a phased array device could overcome the large focal region limitations faced by single transducer treatment devices. Effects of the size, shape and frequency of the array on its focal region were considered. It was found that a λ/2 spaced array of 7680 elements operating at 500 kHz could consistently focus to a region fully contained within the femoral vein. Furthermore, it is possible to reduce the number of elements required by building arrays operating at lower frequencies. The results suggest that phased transducer arrays hold potential for developing a safe, non-invasive treatment of thrombolysis.

  19. Biologically templated assembly of hybrid semiconducting nanomesh for high performance field effect transistors and sensors

    Science.gov (United States)

    Byeon, Hye-Hyeon; Lee, Seung-Woo; Lee, Eun-Hee; Kim, Woong; Yi, Hyunjung

    2016-10-01

    Delicately assembled composites of semiconducting nanomaterials and biological materials provide an attractive interface for emerging applications, such as chemical/biological sensors, wearable health monitoring devices, and therapeutic agent releasing devices. The nanostructure of composites as a channel and a sensing material plays a critical role in the performance of field effect transistors (FETs). Therefore, it is highly desirable to prepare elaborate composite that can allow the fabrication of high performance FETs and also provide high sensitivity and selectivity in detecting specific chemical/biological targets. In this work, we demonstrate that high performance FETs can be fabricated with a hydrodynamically assembled composite, a semiconducting nanomesh, of semiconducting single-walled carbon nanotubes (S-SWNTs) and a genetically engineered M13 phage to show strong binding affinity toward SWNTs. The semiconducting nanomesh enables a high on/off ratio (~104) of FETs. We also show that the threshold voltage and the channel current of the nanomesh FETs are sensitive to the change of the M13 phage surface charge. This biological gate effect of the phage enables the detection of biologically important molecules such as dopamine and bisphenol A using nanomesh-based FETs. Our results provide a new insight for the preparation of composite material platform for highly controllable bio/electronics interfaces.

  20. Predator interference effects on biological control: The "paradox" of the generalist predator revisited

    Science.gov (United States)

    Parshad, Rana D.; Bhowmick, Suman; Quansah, Emmanuel; Basheer, Aladeen; Upadhyay, Ranjit Kumar

    2016-10-01

    An interesting conundrum in biological control questions the efficiency of generalist predators as biological control agents. Theory suggests, generalist predators are poor agents for biological control, primarily due to mutual interference. However field evidence shows they are actually quite effective in regulating pest densities. In this work we provide a plausible answer to this paradox. We analyze a three species model, where a generalist top predator is introduced into an ecosystem as a biological control, to check the population of a middle predator, that in turn is depredating on a prey species. We show that the inclusion of predator interference alone, can cause the solution of the top predator equation to blow-up in finite time, while there is global existence in the no interference case. This result shows that interference could actually cause a population explosion of the top predator, enabling it to control the target species, thus corroborating recent field evidence. Our results might also partially explain the population explosion of certain species, introduced originally for biological control purposes, such as the cane toad (Bufo marinus) in Australia, which now functions as a generalist top predator. We also show both Turing instability and spatio-temporal chaos in the model. Lastly we investigate time delay effects.

  1. Biologically templated assembly of hybrid semiconducting nanomesh for high performance field effect transistors and sensors

    Science.gov (United States)

    Byeon, Hye-Hyeon; Lee, Seung-Woo; Lee, Eun-Hee; Kim, Woong; Yi, Hyunjung

    2016-01-01

    Delicately assembled composites of semiconducting nanomaterials and biological materials provide an attractive interface for emerging applications, such as chemical/biological sensors, wearable health monitoring devices, and therapeutic agent releasing devices. The nanostructure of composites as a channel and a sensing material plays a critical role in the performance of field effect transistors (FETs). Therefore, it is highly desirable to prepare elaborate composite that can allow the fabrication of high performance FETs and also provide high sensitivity and selectivity in detecting specific chemical/biological targets. In this work, we demonstrate that high performance FETs can be fabricated with a hydrodynamically assembled composite, a semiconducting nanomesh, of semiconducting single-walled carbon nanotubes (S-SWNTs) and a genetically engineered M13 phage to show strong binding affinity toward SWNTs. The semiconducting nanomesh enables a high on/off ratio (~104) of FETs. We also show that the threshold voltage and the channel current of the nanomesh FETs are sensitive to the change of the M13 phage surface charge. This biological gate effect of the phage enables the detection of biologically important molecules such as dopamine and bisphenol A using nanomesh-based FETs. Our results provide a new insight for the preparation of composite material platform for highly controllable bio/electronics interfaces. PMID:27762315

  2. Biologically effective doses of postoperative radiotherapy in the prevention of keloids. Dose-effect relationship

    Energy Technology Data Exchange (ETDEWEB)

    Kal, H.B.; Veen, R.E. [University Medical Center Utrecht (Netherlands). Dept. of Radiotherapy

    2005-11-01

    Purpose: To review the recurrence rates of keloids after surgical excision followed by radiotherapy, and to answer the question whether after normalization of the dose, a dose-effect relationship could be derived. Material and Methods: A literature search was performed to identify studies dealing with the efficacy of various irradiation regimes for the prevention of keloids after surgery. Biologically effective doses (BEDs) of the various irradiation regimens were calculated using the linear-quadratic concept. A distinction between recurrence rates of keloids in the face and neck region and those in other parts of the body was made. Results: 31 reports were identified with PubMed with the search terms keloids, surgery, radiation therapy, radiotherapy. 13 reports were excluded, because no link could be found between recurrence rate and dose, or if less than ten patients per dose group. The recurrence rate for surgery only was 50-80%. For BED values >10 Gy the recurrence rate decreased as a function of BED. For BED values >30 Gy the recurrence rate was <10%. For a given dose, the recurrence rates of keloids in the sites with high stretch tension were not significantly higher than in sites without stretch tension. Conclusion: The results of this study indicate that for effectively treating keloids postoperatively, a relatively high dose must be applied in a short overall treatment time. The optimal treatment probably is an irradiation scheme resulting in a BED value of at least 30 Gy. A BED value of 30 Gy can be obtained with, for instance, a single acute dose of 13 Gy, two fractions of 8 Gy two fractions of 8 Gy or three fractions of 6 Gy, or a single dose of 27 Gy at low dose rate. The radiation treatment should be administered within 2 days after surgery. (orig.)

  3. Simulation of the radiation effects on biological objects; Simulation der Strahlenwirkung auf biologische Objekte

    Energy Technology Data Exchange (ETDEWEB)

    Bug, Marion; Nettelbeck, Heidi [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany). Arbeitsgruppe ' Biologische Wirksamkeit Ionisierender Strahlung'

    2013-06-15

    The simulation of biological radiation effects by means of the electron transport in water and DNA and the cross sections for elastic scattering, electronic excitation, and ionization in electron collisions with tetrahydrofuran molecules is described, whereby the strand-breaking probabilities are determined. (HSI)

  4. Genotoxic exposure and biological effects in the rubber manufacturing industry. Relevance of the dermal route

    NARCIS (Netherlands)

    Vermeulen, R.

    2001-01-01

    This thesis describes an industry wide survey on genotoxic exposure and biological effects in the rubber manifacturing industry. Chapters are devoted to long-term trends in inhalable and dermal contamination levels, identification of dermal exposure pathways and the assessment of mutagenic

  5. Fertility among HIV-infected Indian women Indian women : the biological effect and its implications

    NARCIS (Netherlands)

    Darak, Shrinivas; Janssen, Fanny; Hutter, Inge

    In India, nearly one million women of childbearing age are infected with HIV. This study sought to examine the biological effect of HIV on the fertility of HIV-infected Indian women. This is relevant for the provision of pregnancy-related counselling and care to the infected women, and for

  6. Effects of Developed Electronic Instructional Medium on Students' Achievement in Biology

    Science.gov (United States)

    Chinna, Nsofor Caroline; Dada, Momoh Gabriel

    2013-01-01

    The study investigated the effects of developed electronic instructional medium (video DVD instructional package) on students' achievement in Biology. It was guided by two research questions and two hypotheses, using a quasi-experimental, pretest-postest control group design. The sample comprised of 180 senior secondary, year two students from six…

  7. Fertility among HIV-infected Indian women Indian women : the biological effect and its implications

    NARCIS (Netherlands)

    Darak, Shrinivas; Janssen, Fanny; Hutter, Inge

    2011-01-01

    In India, nearly one million women of childbearing age are infected with HIV. This study sought to examine the biological effect of HIV on the fertility of HIV-infected Indian women. This is relevant for the provision of pregnancy-related counselling and care to the infected women, and for estimatin

  8. Effects of organic versus conventional management on chemical and biological parameters in agricultural soils

    NARCIS (Netherlands)

    Diepeningen, van A.D.; Vos, de O.J.; Korthals, G.W.; Bruggen, van A.H.C.

    2006-01-01

    A comparative study of organic and conventional arable farming systems was conducted in The Netherlands to determine the effect of management practices on chemical and biological soil properties and soil health. Soils from thirteen accredited organic farms and conventionally managed neighboring farm

  9. Effectiveness of the Biology PTechLS Module in a Felda Science Centre

    Science.gov (United States)

    Alias, Norlidah; DeWitt, Dorothy; Rahman, Mohd Nazri Abdul; Gelamdin, Rashidah Begum; Rauf, Rose Amnah Abd; Siraj, Saedah

    2014-01-01

    The PTechLS module combines learning styles with the use of technology to increase students' learning experience, especially in learning abstract concepts. The PTechLS module prototype was developed by Norlidah Alias (2010). The aim of this study is to evaluate the implementation effectiveness of the Biology PTechLS module in a Felda Learning…

  10. The Effectiveness of the New 9th Grade Biology Curriculum on Students' Environmental Awareness

    Science.gov (United States)

    Cetin, Gulcan; Nisanci, Seda Hilal

    2010-01-01

    The aim of this study was to examine the effectiveness of a new 9th grade biology curriculum on students' environmental awareness. Participants included 91 ninth grade students in a high school in Balikesir during the spring semester of the 2008-2009 academic years. Two classrooms, including 22 and 24 students respectively, were randomly assigned…

  11. Effect of temperature on the biology of Paracoccus marginatus Williams and Granara de Willink (Homoptera: Pseudococcidae).

    Science.gov (United States)

    Abstract: Effect of temperature on the biology of Paracoccus marginatus was investigated. P. marginatus was able to develop and complete its life cycle at 18°, 20°, 25° and 30°C. At 15°, 34° and 35°C eggs hatched, but further development was arrested. Approximately 80 -90% of the eggs survived betw...

  12. The Effectiveness of a Virtual Field Trip (VFT) Module in Learning Biology

    Science.gov (United States)

    Haris, Norbaizura; Osman, Kamisah

    2015-01-01

    Virtual Field Trip is a computer aided module of science developed to study the Colonisation and Succession in Mangrove Swamps, as an alternative to the real field trip in Form for Biology. This study is to identify the effectiveness of the Virtual Field Trip (VFT) module towards the level of achievement in the formative test for this topic. This…

  13. Effectiveness of Blended Cooperative Learning Environment in Biology Teaching: Classroom Community Sense, Academic Achievement and Satisfaction

    Science.gov (United States)

    Yapici, I. Ümit

    2016-01-01

    The aim of this study was to examine the effect of Blended Cooperative Learning Environment (BCLE) in biology teaching on students' classroom community sense, their academic achievement and on their levels of satisfaction. In the study, quantitative and qualitative research methods were used together. The study was carried out with 30 students in…

  14. Why magnetic and electromagnetic effects in biology are irreproducible and contradictory?

    Science.gov (United States)

    Buchachenko, Anatoly

    2016-01-01

    The main source of magnetic and electromagnetic effects in biological systems is now generally accepted and demonstrated in this paper to be radical pair mechanism which implies pairwise generation of radicals in biochemical reactions. This mechanism was convincingly established for enzymatic adenosine triphosphate (ATP) and desoxynucleic acid (DNA) synthesis by using catalyzing metal ions with magnetic nuclei ((25)Mg, (43)Ca, (67)Zn) and supported by magnetic field effects on these reactions. The mechanism, is shown to function in medicine as a medical remedy or technology (trans-cranial magnetic stimulation, nuclear magnetic control of the ATP synthesis in heart muscle, the killing of cancer cells by suppression of DNA synthesis). However, the majority of magnetic effects in biology remain to be irreproducible, contradictory, and enigmatic. Three sources of such a state are shown in this paper to be: the presence of paramagnetic metal ions as a component of enzymatic site or as an impurity in an uncontrollable amount; the property of the radical pair mechanism to function at a rather high concentration of catalyzing metal ions, when at least two ions enter into the catalytic site; and the kinetic restrictions, which imply compatibility of chemical and spin dynamics in radical pair. It is important to keep in mind these factors to properly understand and predict magnetic effects in magneto-biology and biology itself and deliberately use them in medicine.

  15. Biological effects from electric fields associated with high voltage transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    1983-11-01

    Efforts during the past year by the US Department of Energy and the Electric Power Research Institute-funded laboratories to investigate the biological effects from electric fields are described in resume form. Investigations generally have been summarized with objectives, accomplishments of the past year, and some indication of projected studies.

  16. Effects of Conceptual Change Text Based Instruction on Ecology, Attitudes toward Biology and Environment

    Science.gov (United States)

    Çetin, Gülcan; Ertepinar, Hamide; Geban, Ömer

    2015-01-01

    The purpose of this study is to investigate the effects of the conceptual change text based instruction on ninth grade students' understanding of ecological concepts, and attitudes toward biology and environment. Participants were 82 ninth grade students in a public high school in the Northwestern Turkey. A treatment was employed over a five-week…

  17. Biological assessment of effects of combined sewer overflows and storm water discharges.

    NARCIS (Netherlands)

    Lijklema, L.; Roijackers, R.M.M.; Cuppen, J.G.M.

    1989-01-01

    The biological effects of discharges from combined or separated sewer systems are difficult to assess or to predict due to variahilities in concentrations, environmental conditions, morphometry, susceptibility of organisms, seasonality and other factors. A general discussion of the problem results i

  18. Wood smoke particle sequesters cell iron to impact a biological effect.

    Science.gov (United States)

    The biological effect of an inorganic particle (i.e., silica) can be associated with a disruption in cell iron homeostasis. Organic compounds included in particles originating from combustion processes can also complex sources of host cell iron to disrupt metal homeostasis. We te...

  19. Static magnetic fields: A summary of biological interactions, potential health effects, and exposure guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Tenforde, T.S.

    1992-05-01

    Interest in the mechanisms of interaction and the biological effects of static magnetic fields has increased significantly during the past two decades as a result of the growing number of applications of these fields in research, industry and medicine. A major stimulus for research on the bioeffects of static magnetic fields has been the effort to develop new technologies for energy production and storage that utilize intense magnetic fields (e.g., thermonuclear fusion reactors and superconducting magnet energy storage devices). Interest in the possible biological interactions and health effects of static magnetic fields has also been increased as a result of recent developments in magnetic levitation as a mode of public transportation. In addition, the rapid emergence of magnetic resonance imaging as a new clinical diagnostic procedure has, in recent years, provided a strong rationale for defining the possible biological effects of magnetic fields with high flux densities. In this review, the principal interaction mechanisms of static magnetic fields will be described, and a summary will be given of the present state of knowledge of the biological, environmental, and human health effects of these fields.

  20. Synergistic effect of high-intensity focused ultrasound and low-fluence Q-switched Nd:YAG laser in the treatment of the aging neck and décolletage.

    Science.gov (United States)

    Nam, Jae-Hui; Choi, Young-Jun; Lim, Jae Yun; Min, Joon Hong; Kim, Won-Serk

    2017-01-01

    High-intensity focused ultrasound (HIFU) is regarded as an effective skin-lifting device; however, literature regarding treatment of the aging neck and décolletage with HIFU is scarce. Our study aimed to evaluate the efficacy of combination with HIFU and low-fluence Q-switched Nd:YAG (LQSNY) laser on the aging neck and décolletage. Nineteen women were assessed. HIFU at two visits and LQSNY laser at six visits were used to irradiate the neck and chest. At week 16, improvements were rated using the Dedo classification, Fabi/Bolton Chest Wrinkle Scale (FBCWS), and Global Aesthetic Improvement Scales (GAIS). Erythema and melanin indices (EMIs) and cervicomental angle were measured. Subject GAIS and satisfaction were evaluated at follow-up visits. At week 16, neck sagging and chest rhytides were improved on Dedo classification and FBCWS, respectively. Pigmentation and rhytides of the neck and chest were rated as improved in 30 % or more of the subjects by physician GAIS and in approximately 80 % of the subjects by subject GAIS. The above differences seemed to be attributable to the initial expectation level and mild severity pertaining to dress custom in Korea. Eighty-four percent of subjects were satisfied with treatment outcomes. EMIs were decreased on the chest. The combination of HIFU and LQSNY is an effective treatment option to mitigate rhytides and pigmentation of the neck and décolletage.

  1. EFFECTS OF POLLUTANTS ON BIOLOGICAL SYSTEMS. CHAPTER FROM THE ENERGY AND ENVIRONMENT DIVISION ANNUAL REPORT 1979

    Energy Technology Data Exchange (ETDEWEB)

    Authors, Various

    1980-10-01

    Planning a rational energy future requires anticipating the environmental consequences of various technologies. This is difficult to do with precision as the effects of pollutants are often determined by interactions between and among complex physical (abiotic) and biological (biotic) systems. A given pollutant may affect human beings through direct exposure or indirectly through inducing changes to biological systems which humans need to utilize. The concentration of a toxin in the food chain or the destruction of organisms necessary for the maintenance of high quality water are examples of indirect effects. Pollutants can be transformed and/or degraded as they establish residence in various components of an ecosystem. Anticipation and amelioration of pollutant effects involves the integration of a vast range of data. This data includes: (1) physical and chemical characterization cf the pollutant as it enters the environment; (2) determining effects on the various components (biotic and abiotic) within the context of the functioning ecosystem of interest; (3) transformation in movements and/or degradation of the pollutant within that ecosystem and within specific organisms and physical components; and (4) determining a detailed biochemical and biological picture of the interactions of pollutants with particular organisms and/or their cellular components judged salient for various processes. The major programs described below are designed to answer parts of the above fundamental questions relevant to pollutants generated by energy related technologies. Their emphasis is on anticipating consequences to the biological components of various ecosystems. The work ranges from studies involving parts of a single cell (the membranes) to studies involving the whole ecosystem (in the pelagic zone of a lake). The programs take advantage of expertise and technical abilities present at LBL. Two small exploratory projects which were of brief duration and not related to

  2. Information on biological health effects of ionizing radiation and radionuclides: the rule of a web site

    Energy Technology Data Exchange (ETDEWEB)

    Comte, A.; Gaillard-Lecanu, E.; Flury-Herard, A. [CEA Fontenay aux Roses, 92 (France); Ourly, F. [CEA Saclay, 91 - Gif sur Yvette (France); Hemidy, P.; Lallemand, J. [Electricite de France (EDF), Service de Radioprotection, 75 - Paris (France)

    2006-07-01

    The purpose of this project is to provide a source of information on biological and health effects of radionuclides and ionizing radiation in an easy to use format. Reported work is made up of two distinct parts: data sheets for selected radionuclides and a web file. Data sheets: Specific radiation data sheets provide an overview of the properties, the environmental behaviour, the different pathways of human exposure and the biological and health consequences of selected radionuclides. Radionuclides that have been selected are those commonly dealt with in nuclear industry (and in other areas such as medicine) and released to the environment or naturally occurring (plutonium, tritium, carbon 14). Data sheets corresponding to the different radionuclides are based on the main sources of scientific information in dosimetry, epidemiology, radiobiology and radiation protection. These data sheets are intended for radiation protection specialists and physicians. They include: main physical and chemical characteristics, main radiation protection data: dose coefficients (public, workers), dose limits sources, total released estimate (nuclear industry, atmospheric tests, main pathway of human exposure and biological behaviour, biological and health effects, medical supervision, treatment a list of the main references, appendix providing accurate information. Web file: http://www-dsv.cea.fr/doc/carmin{sub e}xt/fond.php This web file provides a source of information on biological and health effects of ionizing radiation and biological basic knowledge of radiation protection. Available for consultation via Internet, compiled information provides, in a same file, subjects as varied as biological mechanisms, ionizing radiations action, biological and health effects, risk assessment This file is mainly intended to assist in informing and training of non-specialist readership (students, teaching on radiation protection basic knowledge. This electronic document is divided in three

  3. STUDY ON THE RELATIONSHIP OF ARSENIC TRIOXIDE-INDUCED BIOLOGICAL EFFECTS AND DEGRADATIONOF PML PROTEINS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To understand whether arsenic trioxide (As2O3)-induced biological effects are associated with degradation of PML proteins. Methods Acute promyelocytic leukemia (APL) cell line NB4, acute T-lymphocytic leukemia cell line Jurkat, acute myeloid leukemia cell line U937, and chronic myelocytic leukemia blast crisis cell line K562 were used as in vitro models. In different cell lines, the As2O3-induced bio- logical effects were determined by cell growth, cell viability, cell morphology, and flow cytometry assay on sub- G1 cell content. The alteration of PML proteins was analyzed by immunofluorescence. Results In terms of growth inhibition and apoptosis induction, 1.0μmol/L As2O3 had different effects on different cell lines. However, degradation of PML proteins occurred in all the cell lines with As2O3 treatment. Conclusion As2O3-induced biological effects may be independent of PML protein degradation.

  4. Status of study on biological and toxicological effects of nanoscale materials

    Institute of Scientific and Technical Information of China (English)

    WANG; Bing; FENG; Weiyue; ZHAO; Yuliang; XING; Gengmei; CH

    2005-01-01

    Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the environment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some exclusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new research field are also discussed.

  5. Biological effects of mercury pollution. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The bibliography contains citations concerning biological and biochemical effects of mercury pollutants on humans, animals, and plants. References cover long-term and short-term experiments, biochemical reaction kinetics, pollution sources, and ecosystems. Mercury poisoning, metabolism, and related diseases are described. Carcinogenicity testing, health risk and assessment, and the effects on food chains are examined. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  6. Biological effects of low-level exposures: a perspective from U.S. EPA scientists.

    OpenAIRE

    Davis, J M; Farland, W H

    1998-01-01

    Biological effects of low-level exposures (BELLE) may be very important in characterizing the potential health risks of environmental pollutants. Before some features of BELLE, such as effects that may be modulated by adaptive or defense mechanisms, can be taken into greater consideration in U.S. Environmental Protection Agency risk assessments, however adequate information on a toxicant's mode of action and answers to other questions are needed.

  7. Biological effects of atmospheric particles on human bronchial epithelial cells. Comparison with diesel exhaust particles.

    Science.gov (United States)

    Baulig, Augustin; Sourdeval, Matthieu; Meyer, Martine; Marano, Francelyne; Baeza-Squiban, Armelle

    2003-01-01

    Epidemiological studies have associated the increase of respiratory disorders with high levels of ambient particulate matter (PM) levels although the underlying biological mechanisms are unclear. PM are a complex mixture of particles with different origins but in urban areas, they mainly contain soots from transport like Diesel exhaust particles (DEP). In order to determine whether PM biological effects can be explained by the presence of DEP, the effects of urban PM, DEP and carbon black particles (CB) were compared on a human bronchial epithelial cell line (16-HBE14o-). Two types of PM were used : reference material (RPM) and PM with an aerodynamic diameter particles. However, DEP and to a lower extent PM inhibited cell proliferation, induced the release of a pro-inflammatory cytokine, GM-CSF, and generated a pro-oxidant state as shown by the increased intracellular peroxides production. By contrast, CB never induced such effects. Nevertheless CB are more endocytosed than DEP whereas PM are the less endocytosed particles. In conclusion, PM induced to a lower extent the same biological effects than DEP in 16-HBE cells suggesting that particle characteristics should be thoroughly considered in order to clearly correlate adverse effects of PM to their composition and to clarify the role of DEP in PM effects.

  8. Is ground cover vegetation an effective biological control enhancement strategy against olive pests?

    Directory of Open Access Journals (Sweden)

    Daniel Paredes

    Full Text Available Ground cover vegetation is often added or allowed to generate to promote conservation biological control, especially in perennial crops. Nevertheless, there is inconsistent evidence of its effectiveness, with studies reporting positive, nil or negative effects on pest control. This might arise from differences between studies at the local scale (e.g. orchard management and land use history, the landscape context (e.g. presence of patches of natural or semi-natural vegetation near the focal orchard, or regional factors, particularly climate in the year of the study. Here we present the findings from a long-term regional monitoring program conducted on four pest species (Bactrocera oleae, Prays oleae, Euphyllura olivina, Saissetia oleae in 2,528 olive groves in Andalusia (Spain from 2006 to 2012. Generalized linear mixed effect models were used to analyze the effect of ground cover on different response variables related to pest abundance, while accounting for variability at the local, landscape and regional scales. There were small and inconsistent effects of ground cover on the abundance of pests whilst local, landscape and regional variability explained a large proportion of the variability in pest response variables. This highlights the importance of local and landscape-related variables in biological control and the potential effects that might emerge from their interaction with practices, such as groundcover vegetation, implemented to promote natural enemy activity. The study points to perennial vegetation close to the focal crop as a promising alternative strategy for conservation biological control that should receive more attention.

  9. Is ground cover vegetation an effective biological control enhancement strategy against olive pests?

    Science.gov (United States)

    Paredes, Daniel; Cayuela, Luis; Gurr, Geoff M; Campos, Mercedes

    2015-01-01

    Ground cover vegetation is often added or allowed to generate to promote conservation biological control, especially in perennial crops. Nevertheless, there is inconsistent evidence of its effectiveness, with studies reporting positive, nil or negative effects on pest control. This might arise from differences between studies at the local scale (e.g. orchard management and land use history), the landscape context (e.g. presence of patches of natural or semi-natural vegetation near the focal orchard), or regional factors, particularly climate in the year of the study. Here we present the findings from a long-term regional monitoring program conducted on four pest species (Bactrocera oleae, Prays oleae, Euphyllura olivina, Saissetia oleae) in 2,528 olive groves in Andalusia (Spain) from 2006 to 2012. Generalized linear mixed effect models were used to analyze the effect of ground cover on different response variables related to pest abundance, while accounting for variability at the local, landscape and regional scales. There were small and inconsistent effects of ground cover on the abundance of pests whilst local, landscape and regional variability explained a large proportion of the variability in pest response variables. This highlights the importance of local and landscape-related variables in biological control and the potential effects that might emerge from their interaction with practices, such as groundcover vegetation, implemented to promote natural enemy activity. The study points to perennial vegetation close to the focal crop as a promising alternative strategy for conservation biological control that should receive more attention.

  10. The role of cell hydration in realization of biological effects of non-ionizing radiation (NIR).

    Science.gov (United States)

    Ayrapetyan, Sinerik

    2015-09-01

    The weak knowledge on the nature of cellular and molecular mechanisms of biological effects of NIR such as static magnetic field, infrasound frequency of mechanical vibration, extremely low frequency of electromagnetic fields and microwave serves as a main barrier for adequate dosimetry from the point of Public Health. The difficulty lies in the fact that the biological effects of NIR depend not only on their thermodynamic characteristics but also on their frequency and intensity "windows", chemical and physical composition of the surrounding medium, as well as on the initial metabolic state of the organism. Therefore, only biomarker can be used for adequate estimation of biological effect of NIR on organisms. Because of the absence of such biomarker(s), organizations having the mission to monitor hazardous effects of NIR traditionally base their instruction on thermodynamic characteristics of NIR. Based on the high sensitivity to NIR of both aqua medium structure and cell hydration, it is suggested that cell bathing medium is one of the primary targets and cell hydration is a biomarker for NIR effects on cells and organisms. The purpose of this article is to present a short review of literature and our own experimental data on the effects of NIR on plants' seeds germination, microbe growth and development, snail neurons and heart muscle, rat's brain and heart tissues.

  11. Benthic biological effects of seasonal hypoxia in a eutrophic estuary predate rapid coastal development

    Science.gov (United States)

    Bishop, Melanie J.; Powers, Sean P.; Porter, Hugh J.; Peterson, Charles H.

    2006-11-01

    Nutrient and organic loading associated with escalating human activities increases biological oxygen demand from microbial decomposition. In the Neuse River estuary, North Carolina, recurrent nuisance algal blooms, bottom-water hypoxic events, and fish kills during summers of the 1990s suggest that uncapped nutrient loading may have increased the frequency, duration, and/or spatial scope of important biological effects of hypoxia during summer, when persistent water column stratification can occur and microbial metabolism is greatest. We test the hypothesis that the severity of benthic biological effects of hypoxia in this estuary has increased over a 30-year period of dramatic human population growth in eastern North Carolina by comparing survival over summer of the benthic bivalve Macoma spp. between historical (1968-1970) and recent (1997-1998) years. Macoma is a demonstrated indicator of oxygen availability, the benthic biomass dominant in the Neuse and other temperate estuaries and the major prey link to higher trophic levels. All three historical summers exhibited patterns of collapse in Macoma populations indistinguishable from the recent summer of severe hypoxia (1997) but distinct from the modest changes documented during the mildly hypoxic summer of 1998. The only Macoma to survive any severely hypoxic summer were those in shallows where oxygen could be renewed by surface mixing. Thus, the biological effects of hypoxia observed in the Neuse River estuary in the late 1990s appear no more severe than 30 years before. Historic rates of organic loading to the Neuse River estuary may have been sufficient to induce widespread and intense hypoxia beneath the surface mixed layer, implying that even if algal blooms are diminished through nutrient reductions, the severity of biological effects of bottom-water hypoxia may not change detectably.

  12. Assessment of the Effectiveness of the Studio Format in Introductory Undergraduate Biology

    Science.gov (United States)

    Rintoul, David A.; Williams, Larry G.

    2008-01-01

    Kansas State University converted its introductory biology course, previously taught as an audio-tutorial (A-T), to a studio format in 1997. We share with others information about the process involved and present assessment data for the studio format course that address 1) student exam performance in A-T and studio; 2) student course grades in A-T and studio; 3) student and instructor perceptions and attitudes for A-T and studio; 4) student performance in subsequent biology courses for A-T and studio; and 5) gains in student learning for the studio course and other traditional lecture/lab courses. Collectively, these measures demonstrate that the studio format is as effective as or more effective (for some measures) than the A-T approach and traditional approaches in providing an effective learning environment. We discuss the issues involved in comparing course formats. PMID:18519615

  13. Plant ecdysteroids: plant sterols with intriguing distributions, biological effects and relations to plant hormones.

    Science.gov (United States)

    Tarkowská, Danuše; Strnad, Miroslav

    2016-09-01

    The present review summarises current knowledge of phytoecdysteroids' biosynthesis, distribution within plants, biological importance and relations to plant hormones. Plant ecdysteroids (phytoecdysteroids) are natural polyhydroxylated compounds that have a four-ringed skeleton, usually composed of either 27 carbon atoms or 28-29 carbon atoms (biosynthetically derived from cholesterol or other plant sterols, respectively). Their physiological roles in plants have not yet been confirmed and their occurrence is not universal. Nevertheless, they are present at high concentrations in various plant species, including commonly consumed vegetables, and have a broad spectrum of pharmacological and medicinal properties in mammals, including hepatoprotective and hypoglycaemic effects, and anabolic effects on skeletal muscle, without androgenic side-effects. Furthermore, phytoecdysteroids can enhance stress resistance by promoting vitality and enhancing physical performance; thus, they are considered adaptogens. This review summarises current knowledge of phytoecdysteroids' biosynthesis, distribution within plants, biological importance and relations to plant hormones.

  14. Distinct biological effects of different nanoparticles commonly used in cosmetics and medicine coatings

    Directory of Open Access Journals (Sweden)

    Yu Julia X

    2011-05-01

    Full Text Available Abstract Background Metal oxides in nanoparticle form such as zinc oxide and titanium dioxide now appear on the ingredient lists of household products as common and diverse as cosmetics, sunscreens, toothpaste, and medicine. Previous studies of zinc oxide and titanium dioxide in non-nanoparticle format using animals have found few adverse effects. This has led the FDA to classify zinc oxide as GRAS (generally recognized as safe for use as a food additive. However, there is no regulation specific for the use of these chemicals in nanoparticle format. Recent studies, however, have begun to raise concerns over the pervasive use of these compounds in nanoparticle forms. Unfortunately, there is a lack of easily-adaptable screening methods that would allow for the detection of their biological effects. Results We adapted two image-based assays, a fluorescence resonance energy transfer-based caspase activation assay and a green fluorescent protein coupled-LC3 assay, to test for the biological effects of different nanoparticles in a high-throughput format. We show that zinc oxide nanoparticles are cytotoxic. We also show that titanium dioxide nanoparticles are highly effective in inducing autophagy, a cellular disposal mechanism that is often activated when the cell is under stress. Conclusion We suggest that these image-based assays provide a method of screening for the biological effects of similar compounds that is both efficient and sensitive as well as do not involve the use of animals.

  15. Biological Effect of Ultraviolet Photocatalysis on Nanoscale Titanium with a Focus on Physicochemical Mechanism.

    Science.gov (United States)

    Wu, Jingyi; Zhou, Lei; Ding, Xianglong; Gao, Yan; Liu, Xiangning

    2015-09-15

    Physicochemical properties, regulated by various surface modifications, influence the biological performance of materials. The interaction between surface charge and biomolecules is key to understanding the mechanism of surface-tissue integration. The objective of this study was to evaluate the biological response to a nanoscale titanium surface after ultraviolet (UVC, λ = 250 ± 20 nm) irradiation and to analyze the effects via a physicochemical mechanism. The surface characteristics were evaluated by field-emission scanning electron microscopy, X-ray photoelectron spectroscopy, surface profilometry, and contact angle assay. In addition, we applied the zeta-potential, a direct method to measure the electrostatic charge on UV-treated and UV-untreated titanium nanotube surfaces. The effect of the Ti surface after UV treatment on the biological process was determined by analyzing bovine serum albumin (BSA) adsorption and osteoblast-like MG-63 early adhesion, morphology, cytoskeletal arrangement, proliferation, and focal adhesion. Compared to an anodized titanium nanotube coating, UV irradiation altered the contact angles on the control surface from 51.5° to 6.2° without changing the surface topography or roughness. Furthermore, titanium nanotubes after UV treatment showed a significant reduction in the content of acidic hydroxyl groups and held less negative charge than the anodized coating. With regard to the biological response, along with an enhanced capability to adsorb BSA, osteoblasts exhibited higher colonization and viability on the UV-treated material. The results suggest that UV treatment enhances the biocompatibility by reducing the electrostatic repulsion between biomaterials and biomolecules.

  16. In vitro cultured cells as probes for space radiation effects on biological systems

    Energy Technology Data Exchange (ETDEWEB)

    Meli, A.; Perrella, G.; Curcio, F.; Ambesi-Impiombato, F.S. [Dipartimento di Patologia e Medicina Sperimentale e Clinica, Universita di Udine, P.le S. Maria della Misericordia, 33100 Udine (Italy)

    1999-12-06

    Near future scenarios of long-term and far-reaching manned space missions, require more extensive knowledge of all possible biological consequences of space radiation, particularly in humans, on both a long-term and a short-term basis. In vitro cultured cells have significantly contributed to the tremendous advancement of biomedical research. It is therefore to be expected that simple biological systems such as cultured cells, will contribute to space biomedical sciences. Space represents a novel environment, to which life has not been previously exposed. Both microgravity and space radiation are the two relevant components of such an environment, but biological adaptive mechanisms and efficient countermeasures can significantly minimize microgravity effects. On the other hand, it is felt that space radiation risks may be more relevant and that defensive strategies can only stem from our deeper knowledge of biological effects and of cellular repair mechanisms. Cultured cells may play a key role in such studies. Particularly, thyroid cells may be relevant because of the exquisite sensitivity of the thyroid gland to radiation. In addition, a clone of differentiated, normal thyroid follicular cells (FRTL5 cells) is available in culture, which is well characterized and particularly fit for space research.

  17. The effect of cosmic rays on biological systems - an investigation during GLE events

    Science.gov (United States)

    Belisheva, N. K.; Lammer, H.; Biernat, H. K.; Vashenuyk, E. V.

    2012-01-01

    In this study, first direct and circumstantial evidences of the effects of cosmic rays (CR) on biological systems are presented. A direct evidence of biological effects of CR is demonstrated in experiments with three cellular lines growing in culture during three events of Ground Level Enhancement (GLEs) in the neutron count rate detected by ground-based neutron monitor in October 1989. Various phenomena associated with DNA lesion on the cellular level demonstrate coherent dynamics of radiation effects in all cellular lines coincident with the time of arrival of high-energy solar particles to the near-Earth space and with the main peak in GLE. These results were obtained in the course of six separate experiments, with partial overlapping of the time of previous and subsequent experiments, which started and finished in the quiet period of solar activity (SA). A significant difference between the values of multinuclear cells in all cellular lines in the quiet period and during GLE events indicates that the cause of radiation effects in the cell cultures is an exposure of cells to the secondary solar CR near the Earth's surface. The circumstantial evidence was obtained by statistical analysis of cases of congenital malformations (CM) at two sites in the Murmansk region. The number of cases of all classes of CM reveals a significant correlation with the number of GLE events. The number of cases of CM with pronounced chromosomal abnormalities clearly correlates with the GLE events that occurred a year before the birth of a child. We have found a significant correlation between modulations of the water properties and daily background variations of CR intensity. We believe that the effects of CR on biological systems can be also mediated by fluctuations in water properties, considered as one of possible mechanisms controlling the effects of CRs on biological systems.

  18. Effectiveness of biological surrogates for predicting patterns of marine biodiversity: a global meta-analysis.

    Directory of Open Access Journals (Sweden)

    Camille Mellin

    Full Text Available The use of biological surrogates as proxies for biodiversity patterns is gaining popularity, particularly in marine systems where field surveys can be expensive and species richness high. Yet, uncertainty regarding their applicability remains because of inconsistency of definitions, a lack of standard methods for estimating effectiveness, and variable spatial scales considered. We present a Bayesian meta-analysis of the effectiveness of biological surrogates in marine ecosystems. Surrogate effectiveness was defined both as the proportion of surrogacy tests where predictions based on surrogates were better than random (i.e., low probability of making a Type I error; P and as the predictability of targets using surrogates (R(2. A total of 264 published surrogacy tests combined with prior probabilities elicited from eight international experts demonstrated that the habitat, spatial scale, type of surrogate and statistical method used all influenced surrogate effectiveness, at least according to either P or R(2. The type of surrogate used (higher-taxa, cross-taxa or subset taxa was the best predictor of P, with the higher-taxa surrogates outperforming all others. The marine habitat was the best predictor of R(2, with particularly low predictability in tropical reefs. Surrogate effectiveness was greatest for higher-taxa surrogates at a <10-km spatial scale, in low-complexity marine habitats such as soft bottoms, and using multivariate-based methods. Comparisons with terrestrial studies in terms of the methods used to study surrogates revealed that marine applications still ignore some problems with several widely used statistical approaches to surrogacy. Our study provides a benchmark for the reliable use of biological surrogates in marine ecosystems, and highlights directions for future development of biological surrogates in predicting biodiversity.

  19. Biological effects of exposure to static electric fields in humans and vertebrates: a systematic review.

    Science.gov (United States)

    Petri, Anne-Kathrin; Schmiedchen, Kristina; Stunder, Dominik; Dechent, Dagmar; Kraus, Thomas; Bailey, William H; Driessen, Sarah

    2017-04-17

    High-voltage direct current (HVDC) lines are the technology of choice for the transport of large amounts of energy over long distances. The operation of these lines produces static electric fields (EF), but the data reviewed in previous assessments were not sufficient to assess the need for any environmental limit. The aim of this systematic review was to update the current state of research and to evaluate biological effects of static EF. Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) recommendations, we collected and evaluated experimental and epidemiological studies examining biological effects of exposure to static EF in humans (n = 8) and vertebrates (n = 40). There is good evidence that humans and animals are able to perceive the presence of static EF at sufficiently high levels. Hair movements caused by electrostatic forces may play a major role in this perception. A large number of studies reported responses of animals (e.g., altered metabolic, immunologic or developmental parameters) to a broad range of static EF strengths as well, but these responses are likely secondary physiological responses to sensory stimulation. Furthermore, the quality of many of the studies reporting physiological responses is poor, which raises concerns about confounding. The weight of the evidence from the literature reviewed did not indicate that static EF have adverse biological effects in humans or animals. The evidence strongly supported the role of superficial sensory stimulation of hair and skin as the basis for perception of the field, as well as reported indirect behavioral and physiological responses. Physical considerations also preclude any direct effect of static EF on internal physiology, and reports that some physiological processes are affected in minor ways may be explained by other factors. While this literature does not support a level of concern about biological effects of exposure to static EF, the conditions

  20. State-of-the-art exposure chamber for highly controlled and reproducible THz biological effects studies

    Science.gov (United States)

    Cerna, Cesario Z.; Elam, David P.; Echchgadda, Ibtissam; Sloan, Mark A.; Wilmink, Gerald J.

    2014-03-01

    Terahertz (THz) imaging and sensing technologies are increasingly being used at international airports for security screening purposes and at major medical centers for cancer and burn diagnosis. The emergence of new THz applications has directly resulted in an increased interest regarding the biological effects associated with this frequency range. Knowledge of THz biological effects is also desired for the safe use of THz systems, identification of health hazards, and development of empirically-based safety standards. In this study, we developed a state-of-the-art exposure chamber that allowed for highly controlled and reproducible studies of THz biological effects. This innovative system incorporated an industry grade cell incubator system that permitted a highly controlled exposure environment, where temperatures could be maintained at 37 °C +/- 0.1 °C, carbon dioxide (CO2) levels at 5% +/- 0.1%, and relative humidity (RH) levels at 95% +/- 1%. To maximize the THz power transmitted to the cell culture region inside the humid incubator, a secondary custom micro-chamber was fabricated and incorporated into the system. This micro-chamber shields the THz beam from the incubator environment and could be nitrogen-purged to eliminate water absorption effects. Additionally, a microscope that allowed for real-time visualization of the live cells before, during, and after THz exposure was integrated into the exposure system.

  1. The Cost-Effectiveness of Biologics for the Treatment of Rheumatoid Arthritis: A Systematic Review

    Science.gov (United States)

    Joensuu, Jaana T.; Huoponen, Saara; Aaltonen, Kalle J.; Konttinen, Yrjö T.; Nordström, Dan; Blom, Marja

    2015-01-01

    Background and Objectives Economic evaluations provide information to aid the optimal utilization of limited healthcare resources. Costs of biologics for Rheumatoid arthritis (RA) are remarkably high, which makes these agents an important target for economic evaluations. This systematic review aims to identify existing studies examining the cost-effectiveness of biologics for RA, assess their quality and report their results systematically. Methods A literature search covering Medline, Scopus, Cochrane library, ACP Journal club and Web of Science was performed in March 2013. The cost-utility analyses (CUAs) of one or more available biological drugs for the treatment of RA in adults were included. Two independent investigators systematically collected information and assessed the quality of the studies. To enable the comparison of the results, all costs were converted to 2013 euro. Results Of the 4890 references found in the literature search, 41 CUAs were included in the current systematic review. While considering only direct costs, the incremental cost-effectiveness ratio (ICER) of the tumor necrosis factor inhibitors (TNFi) ranged from 39,000 to 1 273,000 €/quality adjusted life year (QALY) gained in comparison to conventional disease-modifying antirheumatic drugs (cDMARDs) in cDMARD naïve patients. Among patients with an insufficient response to cDMARDs, biologics were associated with ICERs ranging from 12,000 to 708,000 €/QALY. Rituximab was found to be the most cost-effective alternative compared to other biologics among the patients with an insufficient response to TNFi. Conclusions When 35,000 €/QALY is considered as a threshold for the ICER, TNFis do not seem to be cost-effective among cDMARD naïve patients and patients with an insufficient response to cDMARDs. With thresholds of 50,000 to 100,000 €/QALY biologics might be cost-effective among patients with an inadequate response to cDMARDs. Standardization of multiattribute utility instruments

  2. The cost-effectiveness of biologics for the treatment of rheumatoid arthritis: a systematic review.

    Directory of Open Access Journals (Sweden)

    Jaana T Joensuu

    Full Text Available Economic evaluations provide information to aid the optimal utilization of limited healthcare resources. Costs of biologics for Rheumatoid arthritis (RA are remarkably high, which makes these agents an important target for economic evaluations. This systematic review aims to identify existing studies examining the cost-effectiveness of biologics for RA, assess their quality and report their results systematically.A literature search covering Medline, Scopus, Cochrane library, ACP Journal club and Web of Science was performed in March 2013. The cost-utility analyses (CUAs of one or more available biological drugs for the treatment of RA in adults were included. Two independent investigators systematically collected information and assessed the quality of the studies. To enable the comparison of the results, all costs were converted to 2013 euro.Of the 4890 references found in the literature search, 41 CUAs were included in the current systematic review. While considering only direct costs, the incremental cost-effectiveness ratio (ICER of the tumor necrosis factor inhibitors (TNFi ranged from 39,000 to 1,273,000 €/quality adjusted life year (QALY gained in comparison to conventional disease-modifying antirheumatic drugs (cDMARDs in cDMARD naïve patients. Among patients with an insufficient response to cDMARDs, biologics were associated with ICERs ranging from 12,000 to 708,000 €/QALY. Rituximab was found to be the most cost-effective alternative compared to other biologics among the patients with an insufficient response to TNFi.When 35,000 €/QALY is considered as a threshold for the ICER, TNFis do not seem to be cost-effective among cDMARD naïve patients and patients with an insufficient response to cDMARDs. With thresholds of 50,000 to 100,000 €/QALY biologics might be cost-effective among patients with an inadequate response to cDMARDs. Standardization of multiattribute utility instruments and a validated standard conversion method

  3. Elucidation of the role of biological factors and device design in cerebral NIRS using an in vivo hematoma model based on high-intensity focused ultrasound

    Science.gov (United States)

    Wang, Jianting; Huang, Stanley; Myers, Matthew; Chen, Yu; Welle, Cristin; Pfefer, Joshua

    2016-03-01

    Near-Infrared Spectroscopy (NIRS) is an emerging medical countermeasure for rapid, field detection of hematomas caused by traumatic brain injury (TBI). Bench and animal tests to determine NIRS sensitivity and specificity are needed. However, current animal models involving non-invasively induced, localized neural damage are limited. We investigated an in vivo murine hematoma model in which cerebral hemorrhage was induced noninvasively by high-intensity focused ultrasound (HIFU) with calibrated positioning and parameters. To characterize the morphology of induced hematomas, we used skull-intact histological evaluation. A multi-wavelength fiber-optic NIRS system with three source-detector separation distances was used to detect hematoma A 1.1 MHz transducer produced consistent small-to-medium hematoma localized to a single hemisphere, along with bruising of the scalp, with a low mortality rate. A 220 kHz transducer produced larger, more diffuse hematomas, with higher variability in size and a correspondingly higher mortality rate. No skin bruising or blood accumulation between the skin and skull was observed following injury application with the 220 kHz transducer. Histological analysis showed higher sensitivity for larger hematomas (>4x4 mm2). NIRS optical density change after HIFU was able to detect all hematomas, with sensitivity dependent on wavelength and separation distance. While improvements in methods for validating cerebral blood distribution are needed, the HIFU hematoma model provided useful insights that will inform development of biologically relevant, performance test methods for cerebral NIRS systems.

  4. Effective diffusion coefficient of biological liquids in porous calcium phosphate coatings

    Science.gov (United States)

    Nazarenko, N. N.; Knyazeva, A. G.

    2016-11-01

    The study offers a method to estimate effective diffusion coefficients for transfer of biological liquids in porous materials. The method is based on the analysis of areas occupied by pores and solid materials on slice images. The possibility is shown for ascertaining a correlation between the effective coefficient and technological conditions because different structure and porosity are observed experimentally. The correlations of effective diffusion coefficients with the production voltage for different coating-base compositions, on which the coating was grown, have been built.

  5. Genomic instability and bystander effects: a paradigm shift in radiation biology?

    Science.gov (United States)

    Morgan, William F.

    2002-01-01

    A basic paradigm in radiobiology is that, following exposure to ionizing radiation, the deposition of energy in the cell nucleus and the resulting damage to DNA, the principal target, are responsible for the radiation's deleterious biological effects. Findings in two rapidly expanding fields of research--radiation-induced genomic instability and bystander effects--have caused us to reevaluate these central tenets. In this article, the potential influence of induced genomic instability and bystander effects on cellular injury after exposure to low-level radiation will be reviewed.

  6. Effect of some botanical materials on certain biological aspects of the house fly, Musca domestica L

    Directory of Open Access Journals (Sweden)

    Nabawy A. I. Elkattan, Khalafalla S. Ahmed, Saadya M. Elbermawy and Rabab

    2011-04-01

    Full Text Available The effects of Lantana camara (leaves, Pelargonium zonale (leaves, Cupressus macrocarpa (leaves, Cyperus rotundus (whole plant and Acacia nilotica (seeds powders on some biological aspects of house fly, M. domestica L. were tested. The effects of three lethal concentrations LC25, LC50 and LC75 on the larval duration, pupation percent, pupal weight, pupal duration, adult emergence percent, sex ratio, adult longevity, and fecundity were determined. The induced malformed larvae, pupae and adults were recorded and photographed. The powders of the five plants were found to have promising effects in controlling this insect.

  7. Glyphosate accumulation, translocation, and biological effects in Coffea arabica after single and multiple exposures

    DEFF Research Database (Denmark)

    Schrübbers, Lars Christoph; Valverde, Bernal E.; Strobel, Bjarne W.

    2016-01-01

    In perennial crops like coffee, glyphosate drift exposure can occur multiple times during its commercial life span. Due to limited glyphosate degradation in higher plants, a potential accumulation of glyphosate could lead to increased biological effects with increased exposure frequency....... In this study, we investigated glyphosate translocation over time, and its concentration and biological effects after single and multiple simulated spray-drift exposures. Additionally, shikimic acid/glyphosate ratios were used as biomarkers for glyphosate binding to its target enzyme.Four weeks after...... the exposure, glyphosate was continuously translocated. Shikimic acid levels were lin-ear correlated with glyphosate levels. After two months, however, glyphosate appeared to have reduced activity. In the greenhouse, multiple applications resulted in higher internal glyphosate concentrations.The time...

  8. Characterization of the angular memory effect of scattered light in biological tissues

    CERN Document Server

    Schott, Sam; Léger, Jean-Francois; Bourdieu, Laurent; Gigan, Sylvain

    2015-01-01

    High resolution optical microscopy is essential in neuroscience but suffers from scattering in biological tissues. It therefore grants access to superficial layers only. Recently developed techniques use scattered photons for imaging by exploiting angular correlations in transmitted light and could potentially increase imaging depths. But those correlations (`angular memory effect') are of very short range and, in theory, only present behind and not inside scattering media. From measurements on neural tissues and complementary simulations, we find that strong forward scattering in biological tissues can enhance the memory effect range (and thus the possible field-of-view) by more than an order of magnitude compared to isotropic scattering for $\\sim$1\\,mm thick tissue layers.

  9. Biological effects induced by K photo-ionisation in and near constituent atoms of DNA

    Energy Technology Data Exchange (ETDEWEB)

    Touati, A.; Herve du Penhoot, M.A.; Fayard, B.; Champion, C.; Abel, F.; Gobert, F.; Lamoureux, M.; Politis, M.F.; Martins, L.; Ricoul, M.; Sabatier, L.; Sage, E.; Chetioui, A

    2002-07-01

    In order to assess the lethal efficiency and other biological effects of inner shell ionisations of constituent atoms of DNA ('K' events), experiments were developed at the LURE synchrotron facility using ultrasoft X rays as a probe of K events. The lethal efficiency of ultrasoft X rays above the carbon K threshold was especially investigated using V79 cells and compared with their efficiency to induce double strand breaks in dry plasmid-DNA. A correlation between the K event efficiencies for these processes is shown. Beams of 340 eV were found to be twice as efficient at killing cells than were beams at 250 eV. In addition, a rough two-fold increase of the relative biological effectiveness for dicentric+ring induction has also been observed between 250 and 340 eV radiations. (author)

  10. Characterization of the angular memory effect of scattered light in biological tissues

    Science.gov (United States)

    Schott, Sam; Bertolotti, Jacopo; Léger, Jean-Francois; Bourdieu, Laurent; Gigan, Sylvain

    2015-05-01

    High resolution optical microscopy is essential in neuroscience but suffers from scattering in biological tissues. It therefore grants access to superficial layers only. Recently developed techniques use scattered photons for imaging by exploiting angular correlations in transmitted light and could potentially increase imaging depths. But those correlations (`angular memory effect') are of very short range and, in theory, only present behind and not inside scattering media. From measurements on neural tissues and complementary simulations, we find that strong forward scattering in biological tissues can enhance the memory effect range (and thus the possible field-of-view) by more than an order of magnitude compared to isotropic scattering for $\\sim$1\\,mm thick tissue layers.

  11. Characterization of the angular memory effect of scattered light in biological tissues.

    Science.gov (United States)

    Schott, Sam; Bertolotti, Jacopo; Léger, Jean-Francois; Bourdieu, Laurent; Gigan, Sylvain

    2015-05-18

    High resolution optical microscopy is essential in neuroscience but suffers from scattering in biological tissues and therefore grants access to superficial brain layers only. Recently developed techniques use scattered photons for imaging by exploiting angular correlations in transmitted light and could potentially increase imaging depths. But those correlations ('angular memory effect') are of a very short range and should theoretically be only present behind and not inside scattering media. From measurements on neural tissues and complementary simulations, we find that strong forward scattering in biological tissues can enhance the memory effect range and thus the possible field-of-view by more than an order of magnitude compared to isotropic scattering for ∼1 mm thick tissue layers.

  12. Computation of the effective mechanical response of biological networks accounting for large configuration changes.

    Science.gov (United States)

    El Nady, K; Ganghoffer, J F

    2016-05-01

    The asymptotic homogenization technique is involved to derive the effective elastic response of biological membranes viewed as repetitive beam networks. Thereby, a systematic methodology is established, allowing the prediction of the overall mechanical properties of biological membranes in the nonlinear regime, reflecting the influence of the geometrical and mechanical micro-parameters of the network structure on the overall response of the equivalent continuum. Biomembranes networks are classified based on nodal connectivity, so that we analyze in this work 3, 4 and 6-connectivity networks, which are representative of most biological networks. The individual filaments of the network are described as undulated beams prone to entropic elasticity, with tensile moduli determined from their persistence length. The effective micropolar continuum evaluated as a continuum substitute of the biological network has a kinematics reflecting the discrete network deformation modes, involving a nodal displacement and a microrotation. The statics involves the classical Cauchy stress and internal moments encapsulated into couple stresses, which develop internal work in duality to microcurvatures reflecting local network undulations. The relative ratio of the characteristic bending length of the effective micropolar continuum to the unit cell size determines the relevant choice of the equivalent medium. In most cases, the Cauchy continuum is sufficient to model biomembranes. The peptidoglycan network may exhibit a re-entrant hexagonal configuration due to thermal or pressure fluctuations, for which micropolar effects become important. The homogenized responses are in good agreement with FE simulations performed over the whole network. The predictive nature of the employed homogenization technique allows the identification of a strain energy density of a hyperelastic model, for the purpose of performing structural calculations of the shape evolutions of biomembranes.

  13. Cumulative and Synergistic Effects of Physical, Biological, and Acoustic Signals on Marine Mammal Habitat Use

    Science.gov (United States)

    2013-10-28

    seasonal breakup of the ice has begun. The bowhead whales detections finally disappear as these mammals begin their annual migration to the Arctic Ocean...Final Report Cumulative and Synergistic Effects of Physical, Biological, and Acoustic Signals on Marine Mammal Habitat Use Jeffrey A Nystuen...signals impact marine mammal habitat use. This is especially critical in areas like the Bering Sea where global climate change can lead to rapid changes

  14. Effectiveness of Biology-Based Methods for Inhibiting Orthodontic Tooth Movement. A Systematic Review.

    Science.gov (United States)

    Cadenas de Llano-Pérula, M; Yañez-Vico, R M; Solano-Reina, E; Palma-Fernandez, J C; Iglesias-Linares, A

    2017-09-22

    Several experimental studies in the literature have tested different biology-based methods for inhibiting or decreasing orthodontic tooth movement (OTM) in humans. This systematic review investigated the effects of these interventions on the rate of tooth movement. Electronic [MedLine; SCOPUS; Cochrane Library; OpenGrey;Web of Science] and manual searches were conducted up to January 26th, 2016 in order to identify publications of clinical trials that compared the decreasing or inhibiting effects of different biology-based methods over OTM in humans. A primary outcome (rate of OTM deceleration/inhibition) and a number of secondary outcomes were examined (clinical applicability, orthodontic force used, possible side effects). Two reviewers selected the studies complying with the eligibility criteria (PICO format) and assessed risk of bias [Cochrane Collaboration's tool]. Data collection and analysis were performed following the Cochrane recommendations. From the initial electronic search, 3726 articles were retrieved and 5 studies were finally included. Two types of biology-based techniques used to reduce the rate of OTM in humans were described: pharmacological and low-level laser therapy. In the first group, human Relaxin was compared to a placebo and administered orally. It was described as having no effect on the inhibition of OTM in humans after 32 days, while the drug tenoxicam, injected locally, inhibited the rate of OTM by up to 10% in humans after 42 days. In the second group, no statistically significant differences were reported, compared to placebo, for the rate of inhibition of OTM in humans after 90 days of observation when a 860 nm continuous wave GaAlA slow-level laser was used. The currently available data do not allow us to draw definitive conclusions about the use of various pharmacological substances and biology-based therapies in humans able to inhibit or decrease the OTM rate. There is an urgent need for more sound well-designed randomized

  15. Effects of organic amendment on soil quality as assessed by biological indicators

    OpenAIRE

    Sultana, Salma

    2011-01-01

    Soil quality decline is one of the most predominant effect deriving from human activities. In particular, intensive agricultural management can affect negatively soils, principally due to rapid depletion of soil organic matter, that affects, in turn, soil physical, chemical and biological properties. The declining trend of soil quality coupled with mismanagement of agricultural production is pose a serious threat to sustainability of intensive agriculture. Sustainable intensive agriculture is...

  16. Effect of non-crop vegetation types on conservation biological control of pests in olive groves

    OpenAIRE

    2013-01-01

    Conservation biological control (CBC) is an environmentally sound potential alternative to the use of chemical insecticides. It involves modifications of the environment to promote natural enemy activity on pests. Despite many CBC studies increasing abundance of natural enemies, there are far fewer demonstrations of reduced pest density and very little work has been conducted in olive crops. In this study we investigated the effects of four forms of non-crop vegetation on the abundance of two...

  17. Biological Effects of Short, High-Level Exposure to Gases: Nitrogen Oxides.

    Science.gov (United States)

    1980-07-01

    SUPPLEMENTARY NOT ES3 This project was one of four under the same contract; the others covered ammonia , carbon monoxide, and sulfur dioxide. 3 IS. KEY wOROS...characterize the biological responses to short, high-level exposures to four gases associated with certain Army weapons systems ( ammonia , carbon monoxide...20- i --- 7 (2) Biochemical and Other Effects Buckley and BalchumlO found biochemical changes, principally in enzyme activity of the liver, spleen

  18. [Properties and biological effect of dust of various artificial mineral fibers].

    Science.gov (United States)

    Elovskaja, L T; Werner, I; Kupina, L M; Loscilov, J A; Efremov, L D

    1990-09-01

    Developments and use of man-made mineral fibres are important for the progress in some technical fields. In the last years the number of man-made mineral fibres increased extraordinarily. For the medical evaluation it is necessary to determine the physico-chemical characteristics of the man-made mineral fibre dust and its biological effects in animal experiments. The results of the investigations are described.

  19. Effect of the flavonoid rutin on the biology of Spodoptera frugiperda (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    Talita Roberta Ferreira Borges Silva

    2016-04-01

    Full Text Available The fall armyworm Spodoptera frugiperda (J.E. Smith (Lepidoptera: Noctuidae is a major pest of maize crops in Brazil. The effects of plant metabolites on the biology and behavior of insects is little studied. The aim of the study was to evaluate the activity of rutin on the biology of the S. frugiperda by using artificial diets containing rutin. The study evaluated four treatments: regular diet (control group and diets containing 1.0, 2.0 and 3.0 mg g-1 of rutin. The following biological variables parameters of the larvae were evaluated daily: development time (days, larval and pupal weight (g and viability (%, adult longevity and total life cycle (days. A completely randomized experimental design was used with 25 replication. The rutin flavonoid negatively affected the biology of S. frugiperda by prolonging the larval development time, reducing the weight of larvae and pupae and decreasing the viability of the pupae. The addition of different concentrations of rutin prolonged the S. frugiperda life cycle. The use of plant with insecticidal activity has the potential with strategy in IPM.

  20. Effectiveness of computer-assisted learning in biology teaching in primary schools in Serbia

    Directory of Open Access Journals (Sweden)

    Županec Vera

    2013-01-01

    Full Text Available The paper analyzes the comparative effectiveness of Computer-Assisted Learning (CAL and the traditional teaching method in biology on primary school pupils. A stratified random sample consisted of 214 pupils from two primary schools in Novi Sad. The pupils in the experimental group learned the biology content (Chordate using CAL, whereas the pupils in the control group learned the same content using traditional teaching. The research design was the pretest-posttest equivalent groups design. All instruments (the pretest, the posttest and the retest contained the questions belonging to three different cognitive domains: knowing, applying, and reasoning. Arithmetic mean, standard deviation, and standard error were analyzed using the software package SPSS 14.0, and t-test was used in order to establish the difference between the same statistical indicators. The analysis of results of the post­test and the retest showed that the pupils from the CAL group achieved significantly higher quantity and quality of knowledge in all three cognitive domains than the pupils from the traditional group. The results accomplished by the pupils from the CAL group suggest that individual CAL should be more present in biology teaching in primary schools, with the aim of raising the quality of biology education in pupils. [Projekat Ministarstva nauke Republike Srbije, br. 179010: Quality of Educational System in Serbia in the European Perspective

  1. On the effect of prestrain and residual stress in thin biological membranes.

    Science.gov (United States)

    Rausch, Manuel K; Kuhl, Ellen

    2013-09-01

    Understanding the difference between ex vivo and in vivo measurements is critical to interpret the load carrying mechanisms of living biological systems. For the past four decades, the ex vivo stiffness of thin biological membranes has been characterized using uniaxial and biaxial tests with remarkably consistent stiffness parameters, even across different species. Recently, the in vivo stiffness was characterized using combined imaging techniques and inverse finite element analyses. Surprisingly, ex vivo and in vivo stiffness values differed by up to three orders of magnitude. Here, for the first time, we explain this tremendous discrepancy using the concept of prestrain. We illustrate the mathematical modeling of prestrain in nonlinear continuum mechanics through the multiplicative decomposition of the total elastic deformation into prestrain-induced and load-induced parts. Using in vivo measured membrane kinematics and associated pressure recordings, we perform an inverse finite element analysis for different prestrain levels and show that the resulting membrane stiffness may indeed differ by four orders of magnitude depending on the prestrain level. Our study motivates the hypothesis that prestrain is important to position thin biological membranes in vivo into their optimal operating range, right at the transition point of the stiffening regime. Understanding the effect of prestrain has direct clinical implications in regenerative medicine, medical device design, and and tissue engineering of replacement constructs for thin biological membranes.

  2. Deciphering the biological effects of acupuncture treatment modulating multiple metabolism pathways.

    Science.gov (United States)

    Zhang, Aihua; Yan, Guangli; Sun, Hui; Cheng, Weiping; Meng, Xiangcai; Liu, Li; Xie, Ning; Wang, Xijun

    2016-02-16

    Acupuncture is an alternative therapy that is widely used to treat various diseases. However, detailed biological interpretation of the acupuncture stimulations is limited. We here used metabolomics and proteomics technology, thereby identifying the serum small molecular metabolites into the effect and mechanism pathways of standardized acupuncture treatments at 'Zusanli' acupoint which was the most often used acupoint in previous reports. Comprehensive overview of serum metabolic profiles during acupuncture stimulation was investigated. Thirty-four differential metabolites were identified in serum metabolome and associated with ten metabolism pathways. Importantly, we have found that high impact glycerophospholipid metabolism, fatty acid metabolism, ether lipid metabolism were acutely perturbed by acupuncture stimulation. As such, these alterations may be useful to clarify the biological mechanism of acupuncture stimulation. A series of differentially expressed proteins were identified and such effects of acupuncture stimulation were found to play a role in transport, enzymatic activity, signaling pathway or receptor interaction. Pathway analysis further revealed that most of these proteins were found to play a pivotal role in the regulation of multiple metabolism pathways. It demonstrated that the metabolomics coupled with proteomics as a powerful approach for potential applications in understanding the biological effects of acupuncture stimulation.

  3. Relative biological effectiveness for photons: implication of complex DNA double-strand breaks as critical lesions

    Science.gov (United States)

    Liang, Ying; Fu, Qibin; Wang, Xudong; Liu, Feng; Yang, Gen; Luo, Chunxiong; Ouyang, Qi; Wang, Yugang

    2017-03-01

    Current knowledge in radiobiology ascribes the adverse biological effects of ionizing radiation primarily to the induction of DNA double-strand breaks (DSBs), which is supposed to be potentially lethal and may be converted to lethal damage due to misrepair. Soft and ultrasoft x-rays have been found to bear elevated biological effectiveness for cell killing compared with conventional x-rays or 60Co γ-rays. This phenomenon is qualitatively interpreted as the increased level of DSB induction for low energy photons, however, a thorough quantitative reasoning is lacking. Here, we systematically compared the relative biological effectiveness (RBE) with relative DSB induction for photons from several hundreds of eV up to MeV. Although there is an approximate two-fold increase in the yields of DSB for low energy photons found in our calculation and a large number of experimental measurements, it is far from enough to account for the three- to four-fold increase in RBE. Further theoretical investigations show that DSB complexity (additional single-strand breaks and base damage within 10 base pairs) increases notably for low energy photons, which largely reconciles the discrepancy between RBE and DSB induction. Our theoretical results are in line with accumulating experimental evidence that complex DSBs are refractory to repair machinery and may contribute predominantly to the formation of lethal damage.

  4. Analysis of MIR-18 results for physical and biological dosimetry: radiation shielding effectiveness in LEO

    Science.gov (United States)

    Cucinotta, F. A.; Wilson, J. W.; Williams, J. R.; Dicello, J. F.

    2000-01-01

    We compare models of radiation transport and biological response to physical and biological dosimetry results from astronauts on the Mir space station. Transport models are shown to be in good agreement with physical measurements and indicate that the ratio of equivalent dose from the Galactic Cosmic Rays (GCR) to protons is about 3/2:1 and that this ratio will increase for exposures to internal organs. Two biological response models are used to compare to the Mir biodosimetry for chromosome aberration in lymphocyte cells; a track-structure model and the linear-quadratic model with linear energy transfer (LET) dependent weighting coefficients. These models are fit to in vitro data for aberration formation in human lymphocytes by photons and charged particles. Both models are found to be in reasonable agreement with data for aberrations in lymphocytes of Mir crew members: however there are differences between the use of LET dependent weighting factors and track structure models for assigning radiation quality factors. The major difference in the models is the increased effectiveness predicted by the track model for low charge and energy ions with LET near 10 keV/micrometers. The results of our calculations indicate that aluminum shielding, although providing important mitigation of the effects of trapped radiation, provides no protective effect from the galactic cosmic rays (GCR) in low-earth orbit (LEO) using either equivalent dose or the number of chromosome aberrations as a measure until about 100 g/cm 2 of material is used.

  5. Nanometallomics: an emerging field studying the biological effects of metal-related nanomaterials.

    Science.gov (United States)

    Li, Yu-Feng; Gao, Yuxi; Chai, Zhifang; Chen, Chunying

    2014-02-01

    Metallomics, focusing on the global and systematic understanding of the metal uptake, trafficking, role and excretion in biological systems, has attracted more and more attention. Metal-related nanomaterials, including metallic and metal-containing nanomaterials, have unique properties compared to their micro-scaled counterparts and therefore require special attention. The small size effect, surface effect, and quantum size effect directly influence the physicochemical properties of nanostructured materials and their fate and behavior in biota. However, to our knowledge, the metallomics itself did not touch this special category of materials yet. Therefore, the term "nanometallomics" is proposed and the systematic study on the absorption, distribution, metabolism, excretion (ADME) behavior of metal-related nanomaterials in biological systems and their interactions with genes, proteins and other biomolecules will be reviewed. The ADME behavior of metal-related nanomaterials in the biological systems is influenced by their physicochemical properties, the exposure route, and the microenvironment of the deposition site. Nanomaterials may not only interact directly or indirectly with genes, proteins and other molecules to cause DNA damage, genotoxicity, immunotoxicity, and cytotoxicity, but also stimulate the immune responses, circumvent tumor resistance and inhibit tumor metastasis. Nanometallomics needs to be integrated with other omics sciences, such as genomics, proteomics and metabolomics, to explore the biomedical data and obtain the overall knowledge of underlying mechanisms, and therefore to improve the application performance and to reduce the potential risk of metal-related nanomaterials.

  6. New insight into the molecular mechanisms of the biological effects of DNA minor groove binders.

    Directory of Open Access Journals (Sweden)

    Xinbo Zhang

    Full Text Available BACKGROUND: Bisbenzimides, or Hoechst 33258 (H258, and its derivative Hoechst 33342 (H342 are archetypal molecules for designing minor groove binders, and widely used as tools for staining DNA and analyzing side population cells. They are supravital DNA minor groove binders with AT selectivity. H342 and H258 share similar biological effects based on the similarity of their chemical structures, but also have their unique biological effects. For example, H342, but not H258, is a potent apoptotic inducer and both H342 and H258 can induce transgene overexpression in in vitro studies. However, the molecular mechanisms by which Hoechst dyes induce apoptosis and enhance transgene overexpression are unclear. METHODOLOGY/PRINCIPAL FINDINGS: To determine the molecular mechanisms underlying different biological effects between H342 and H258, microarray technique coupled with bioinformatics analyses and multiple other techniques has been utilized to detect differential global gene expression profiles, Hoechst dye-specific gene expression signatures, and changes in cell morphology and levels of apoptosis-associated proteins in malignant mesothelioma cells. H342-induced apoptosis occurs in a dose-dependent fashion and is associated with morphological changes, caspase-3 activation, cytochrome c mitochondrial translocation, and cleavage of apoptosis-associated proteins. The antagonistic effect of H258 on H342-induced apoptosis indicates a pharmacokinetic basis for the two dyes' different biological effects. Differential global gene expression profiles induced by H258 and H342 are accompanied by unique gene expression signatures determined by DNA microarray and bioinformatics software, indicating a genetic basis for their different biological effects. CONCLUSIONS/SIGNIFICANCE: A unique gene expression signature associated with H342-induced apoptosis provides a new avenue to predict and classify the therapeutic class of minor groove binders in the drug

  7. Novel Biological Approaches for Testing the Contributions of Single DSBs and DSB Clusters to the Biological Effects of High LET Radiation.

    Science.gov (United States)

    Mladenova, Veronika; Mladenov, Emil; Iliakis, George

    2016-01-01

    The adverse biological effects of ionizing radiation (IR) are commonly attributed to the generation of DNA double-strand breaks (DSBs). IR-induced DSBs are generated by clusters of ionizations, bear damaged terminal nucleotides, and frequently comprise base damages and single-strand breaks in the vicinity generating a unique DNA damage-clustering effect that increases DSB "complexity." The number of ionizations in clusters of different radiation modalities increases with increasing linear energy transfer (LET), and is thought to determine the long-known LET-dependence of the relative biological effectiveness (RBE). Multiple ionizations may also lead to the formation of DSB clusters, comprising two or more DSBs that destabilize chromatin further and compromise overall processing. DSB complexity and DSB-cluster formation are increasingly considered in the development of mathematical models of radiation action, which are then "tested" by fitting available experimental data. Despite a plethora of such mathematical models the ultimate goal, i.e., the "a priori" prediction of the radiation effect, has not yet been achieved. The difficulty partly arises from unsurmountable difficulties in testing the fundamental assumptions of such mathematical models in defined biological model systems capable of providing conclusive answers. Recently, revolutionary advances in methods allowing the generation of enzymatic DSBs at random or in well-defined locations in the genome, generate unique testing opportunities for several key assumptions frequently fed into mathematical modeling - including the role of DSB clusters in the overall effect. Here, we review the problematic of DSB-cluster formation in radiation action and present novel biological technologies that promise to revolutionize the way we address the biological consequences of such lesions. We describe new ways of exploiting the I-SceI endonuclease to generate DSB-clusters at random locations in the genome and describe the

  8. Biological Maturity Status Strongly Intensifies the Relative Age Effect in Alpine Ski Racing.

    Science.gov (United States)

    Müller, Lisa; Müller, Erich; Hildebrandt, Carolin; Raschner, Christian

    2016-01-01

    The relative age effect (RAE) is a well-documented phenomenon in youth sports. This effect exists when the relative age quarter distribution of selected athletes shows a biased distribution with an over-representation of relatively older athletes. In alpine ski racing, it exists in all age categories (national youth levels up to World Cup). Studies so far could demonstrate that selected ski racers are relatively older, taller and heavier. It could be hypothesized that relatively younger athletes nearly only have a chance for selection if they are early maturing. However, surprisingly this influence of the biological maturity status on the RAE could not be proven, yet. Therefore, the aim of the present study was to investigate the influence of the biological maturity status on the RAE in dependence of the level of competition. The study investigated 372 elite youth ski racers: 234 provincial ski racers (P-SR; high level of competition) and 137 national ski racers (N-SR; very high level of competition). Anthropometric characteristics were measured to calculate the age at peak height velocity (APHV) as an indicator of the biological maturity status. A significant RAE was present among both P-SR and N-SR, with a larger effect size among the latter group. The N-SR significantly differed in APHV from the P-SR. The distribution of normal, early and late maturing athletes significantly differed from the expected normal distribution among the N-SR, not among the P-SR. Hardly any late maturing N-SR were present; 41.7% of the male and 34% of the female N-SR of the last relative age quarter were early maturing. These findings clearly demonstrate the significant influence of the biological maturity status on the selection process of youth alpine ski racing in dependence of the level of competition. Relatively younger athletes seem to have a chance of selection only if they are early maturing.

  9. Effects of transgenic Bt cotton on soil fertility and biology under field conditions in subtropical inceptisol.

    Science.gov (United States)

    Singh, Raman Jeet; Ahlawat, I P S; Singh, Surender

    2013-01-01

    Although there is large-scale adoption of Bt cotton by the farmers because of immediate financial gain, there is concern that Bt crops release Bt toxins into the soil environment which reduces soil chemical and biological activities. However, the majorities of such studies were mainly performed under pot experiments, relatively little research has examined the direct and indirect effects of associated cover crop of peanut with fertilization by combined application of organic and inorganic sources of nitrogen under field conditions. We compared soil chemical and biological parameters of Bt cotton with pure crop of peanut to arrive on a valid conclusion. Significantly higher dehydrogenase enzyme activity and KMnO(4)-N content of soil were observed in Bt cotton with cover crop of peanut over pure Bt cotton followed by pure peanut at all the crop growth stages. However, higher microbial population was maintained by pure peanut over intercropped Bt cotton, but these differences were related to the presence of high amount of KMnO(4)-N content of soil. By growing cover crop of peanut between Bt cotton rows, bacteria, fungi, and actinomycetes population increased by 60%, 14%, and 10%, respectively, over Bt cotton alone. Bt cotton fertilized by combined application of urea and farm yard manure (FYM) maintained higher dehydrogenase enzyme activity, KMnO(4)-N content of soil and microbial population over urea alone. Significant positive correlations were observed for dry matter accumulation, dehydrogenase enzyme activity, KMnO(4)-N content, and microbial population of soil of Bt cotton, which indicates no harmful effects of Bt cotton on soil biological parameters and associated cover crop. Our results suggest that inclusion of cover crop of peanut and FYM in Bt cotton enhanced soil chemical and biological parameters which can mask any negative effect of the Bt toxin on microbial activity and thus on enzymatic activities.

  10. Systems Biology and Biomarkers of Early Effects for Occupational Exposure Limit Setting.

    Science.gov (United States)

    DeBord, D Gayle; Burgoon, Lyle; Edwards, Stephen W; Haber, Lynne T; Kanitz, M Helen; Kuempel, Eileen; Thomas, Russell S; Yucesoy, Berran

    2015-01-01

    In a recent National Research Council document, new strategies for risk assessment were described to enable more accurate and quicker assessments. This report suggested that evaluating individual responses through increased use of bio-monitoring could improve dose-response estimations. Identification of specific biomarkers may be useful for diagnostics or risk prediction as they have the potential to improve exposure assessments. This paper discusses systems biology, biomarkers of effect, and computational toxicology approaches and their relevance to the occupational exposure limit setting process. The systems biology approach evaluates the integration of biological processes and how disruption of these processes by chemicals or other hazards affects disease outcomes. This type of approach could provide information used in delineating the mode of action of the response or toxicity, and may be useful to define the low adverse and no adverse effect levels. Biomarkers of effect are changes measured in biological systems and are considered to be preclinical in nature. Advances in computational methods and experimental -omics methods that allow the simultaneous measurement of families of macromolecules such as DNA, RNA, and proteins in a single analysis have made these systems approaches feasible for broad application. The utility of the information for risk assessments from -omics approaches has shown promise and can provide information on mode of action and dose-response relationships. As these techniques evolve, estimation of internal dose and response biomarkers will be a critical test of these new technologies for application in risk assessment strategies. While proof of concept studies have been conducted that provide evidence of their value, challenges with standardization and harmonization still need to be overcome before these methods are used routinely.

  11. Biological Maturity Status Strongly Intensifies the Relative Age Effect in Alpine Ski Racing

    Science.gov (United States)

    Müller, Lisa; Müller, Erich; Hildebrandt, Carolin; Raschner, Christian

    2016-01-01

    The relative age effect (RAE) is a well-documented phenomenon in youth sports. This effect exists when the relative age quarter distribution of selected athletes shows a biased distribution with an over-representation of relatively older athletes. In alpine ski racing, it exists in all age categories (national youth levels up to World Cup). Studies so far could demonstrate that selected ski racers are relatively older, taller and heavier. It could be hypothesized that relatively younger athletes nearly only have a chance for selection if they are early maturing. However, surprisingly this influence of the biological maturity status on the RAE could not be proven, yet. Therefore, the aim of the present study was to investigate the influence of the biological maturity status on the RAE in dependence of the level of competition. The study investigated 372 elite youth ski racers: 234 provincial ski racers (P-SR; high level of competition) and 137 national ski racers (N-SR; very high level of competition). Anthropometric characteristics were measured to calculate the age at peak height velocity (APHV) as an indicator of the biological maturity status. A significant RAE was present among both P-SR and N-SR, with a larger effect size among the latter group. The N-SR significantly differed in APHV from the P-SR. The distribution of normal, early and late maturing athletes significantly differed from the expected normal distribution among the N-SR, not among the P-SR. Hardly any late maturing N-SR were present; 41.7% of the male and 34% of the female N-SR of the last relative age quarter were early maturing. These findings clearly demonstrate the significant influence of the biological maturity status on the selection process of youth alpine ski racing in dependence of the level of competition. Relatively younger athletes seem to have a chance of selection only if they are early maturing. PMID:27504832

  12. Biological Effects of Gamma-Ray Bursts: Critical distances for severe damage on the biota

    CERN Document Server

    Galante, D; Galante, Douglas; Horvath, Jorge Ernesto

    2005-01-01

    We present in this work a unified, quantitative synthesis of analytical and numerical calculations of the effects caused on an Earth-like planet by a Gamma-Ray Burst (GRB), considering atmospheric and biological implications. The main effects of the illumination by a GRB are classified in four distinct ones and analyzed separately, namely the direct gamma radiation transmission, UV flash, ozone layer depletion and cosmic rays. The effectiveness of each of these effects is compared and lethal distances for significant biological damage are given for each one. We find that the first three effects have potential to cause global environmental changes and biospheric damages, even if the source is located at great distances (perhaps up to ~ 100 kpc). Instead, cosmic rays would only be a serious threat for very close sources. As a concrete example of a recorded similar event, the effects of the giant flare from SGR1806-20 of Dec 27, 2004 could cause on the biosphere are addressed. In spite of not belonging to the so...

  13. The study of biological effects of electromagnetic mobile phone radiation on experimental animals by combining numerical modeling and experimental research

    Directory of Open Access Journals (Sweden)

    Dejan Krstić

    2012-12-01

    Full Text Available In order to study biological effects of electromagneticradiation, it is essential to know the real values of field componentsthat penetrated the tissue. The study of biological effects is usuallyperformed on experimental animals. The biological effects observedon experimental animals should be linked with penetrating field inthe tissue. The penetrating electromagnetic field is almost impossibleto measure; therefore, modeling process must be carried out and thefield components in models of experimental animals could becalculated. This paper presents an approach to modeling of fieldpenetration and gives contribution to understanding the real effects of the fields and the sensitivity of tissues to electromagnetic radiation generated by mobile phone.

  14. Comparing Effects of Biologic Agents in Treating Patients with Rheumatoid Arthritis: A Multiple Treatment Comparison Regression Analysis.

    Directory of Open Access Journals (Sweden)

    Ingunn Fride Tvete

    Full Text Available Rheumatoid arthritis patients have been treated with disease modifying anti-rheumatic drugs (DMARDs and the newer biologic drugs. We sought to compare and rank the biologics with respect to efficacy. We performed a literature search identifying 54 publications encompassing 9 biologics. We conducted a multiple treatment comparison regression analysis letting the number experiencing a 50% improvement on the ACR score be dependent upon dose level and disease duration for assessing the comparable relative effect between biologics and placebo or DMARD. The analysis embraced all treatment and comparator arms over all publications. Hence, all measured effects of any biologic agent contributed to the comparison of all biologic agents relative to each other either given alone or combined with DMARD. We found the drug effect to be dependent on dose level, but not on disease duration, and the impact of a high versus low dose level was the same for all drugs (higher doses indicated a higher frequency of ACR50 scores. The ranking of the drugs when given without DMARD was certolizumab (ranked highest, etanercept, tocilizumab/ abatacept and adalimumab. The ranking of the drugs when given with DMARD was certolizumab (ranked highest, tocilizumab, anakinra/rituximab, golimumab/ infliximab/ abatacept, adalimumab/ etanercept [corrected]. Still, all drugs were effective. All biologic agents were effective compared to placebo, with certolizumab the most effective and adalimumab (without DMARD treatment and adalimumab/ etanercept (combined with DMARD treatment the least effective. The drugs were in general more effective, except for etanercept, when given together with DMARDs.

  15. Effect of radiation and fungal treatment on ligno celluloses and their biological activity

    Energy Technology Data Exchange (ETDEWEB)

    Lam, N.D.; Nagasawa, Naotsugu; Kume, Tamikazu E-mail: kume@taka.jaeri.go.jp

    2000-10-01

    Effects of high-dose irradiation and fungal treatment on some kinds of lignocellulose material were investigated in order to assess the potential effects of bioactive substances on plants. Each treatment and combination of treatments significantly altered the components of lignocellulose materials. Irradiation strongly affected all plant materials, causing a series of changes in physico-chemical parameters such as solubilization during solvent extraction and losses of fibre components. By these degradations, certain biologically active substances formed and acted as antagonists of auxin-induced growth.

  16. Lethal and Sublethal Effects of Fenpropathrin on the Biological Performance of Scolothrips longicornis (Thysanoptera: Thripidae)

    DEFF Research Database (Denmark)

    Pakyari, Hajar; Enkegaard, Annie

    2013-01-01

    affected the biological characteristics of treated females of S. longicornis, the most noticeable effects being a shortening of female life span by >70% accompanied by large reductions in oviposition period and fecundity. The offspring of females treated with low-lethal concentrations of fenpropathrin...... likewise had significantly reduced longevity, oviposition period, and fecundity, although not to the same extent as experienced by their mothers. Their juvenile development time was, however, not affected. These effects on the offspring were reflected in reduced rates of population increase and increased...

  17. Cost-effective management alternatives for Snake river chinook salmon: A biological-economic synthesis

    Science.gov (United States)

    Halsing, D.L.; Moore, M.R.

    2008-01-01

    The mandate to increase endangered salmon populations in the Columbia River Basin of North America has created a complex, controversial resource-management issue. We constructed an integrated assessment model as a tool for analyzing biological-economic trade-offs in recovery of Snake River spring- and summer-run chinook salmon (Oncorhynchus tshawytscha). We merged 3 frameworks: a salmon-passage model to predict migration and survival of smolts; an age-structured matrix model to predict long-term population growth rates of salmon stocks; and a cost-effectiveness analysis to determine a set of least-cost management alternatives for achieving particular population growth rates. We assessed 6 individual salmon-management measures and 76 management alternatives composed of one or more measures. To reflect uncertainty, results were derived for different assumptions of effectiveness of smolt transport around dams. Removal of an estuarine predator, the Caspian Tern (Sterna caspia), was cost-effective and generally increased long-term population growth rates regardless of transport effectiveness. Elimination of adult salmon harvest had a similar effect over a range of its cost estimates. The specific management alternatives in the cost-effective set depended on assumptions about transport effectiveness. On the basis of recent estimates of smolt transport effectiveness, alternatives that discontinued transportation or breached dams were prevalent in the cost-effective set, whereas alternatives that maximized transportation dominated if transport effectiveness was relatively high. More generally, the analysis eliminated 80-90% of management alternatives from the cost-effective set. Application of our results to salmon management is limited by data availability and model assumptions, but these limitations can help guide research that addresses critical uncertainties and information. Our results thus demonstrate that linking biology and economics through integrated models can

  18. Effects of physical therapy for the management of patients with ankylosing spondylitis in the biological era.

    Science.gov (United States)

    Giannotti, Erika; Trainito, Sabina; Arioli, Giovanni; Rucco, Vincenzo; Masiero, Stefano

    2014-09-01

    Exercise is considered a fundamental tool for the management of ankylosing spondylitis (AS), in combination with pharmacological therapy that with the advent of biological therapy has improved dramatically the control of signs and symptoms of this challenging disease. Current evidence shows that a specific exercise protocol has not been validated yet. The purpose of this review is to update the most recent evidence (July 2010-November 2013) about physiotherapy in AS, analyzing the possible role and synergistic interactions between exercise and biological drugs. From 117 studies initially considered, only 15 were included in the review. The results support a multimodal approach, including educational sessions, conducted in a group setting, supervised by a physiotherapist and followed by a maintaining home-based regimen. Spa exercise and McKenzie, Heckscher, and Pilates methods seem promising in AS rehabilitation, but their effectiveness should be further investigated in future randomized controlled trials (RCTs). When performed in accordance with the American College of Sports Medicine guidelines, cardiovascular training has been proven safe and effective and should be included in AS rehabilitation protocols. Exercise training plays an important role in the biological era, being now applicable to stabilized patients, leading ultimately to a better management of AS by physiatrists and rheumatologists throughout the world. On the basis of the current evidence, further research should aim to determine which exercise protocols should be recommended.

  19. eQTL epistasis: detecting epistatic effects and inferring hierarchical relationships of genes in biological pathways.

    Science.gov (United States)

    Kang, Mingon; Zhang, Chunling; Chun, Hyung-Wook; Ding, Chris; Liu, Chunyu; Gao, Jean

    2015-03-01

    Epistasis is the interactions among multiple genetic variants. It has emerged to explain the 'missing heritability' that a marginal genetic effect does not account for by genome-wide association studies, and also to understand the hierarchical relationships between genes in the genetic pathways. The Fisher's geometric model is common in detecting the epistatic effects. However, despite the substantial successes of many studies with the model, it often fails to discover the functional dependence between genes in an epistasis study, which is an important role in inferring hierarchical relationships of genes in the biological pathway. We justify the imperfectness of Fisher's model in the simulation study and its application to the biological data. Then, we propose a novel generic epistasis model that provides a flexible solution for various biological putative epistatic models in practice. The proposed method enables one to efficiently characterize the functional dependence between genes. Moreover, we suggest a statistical strategy for determining a recessive or dominant link among epistatic expression quantitative trait locus to enable the ability to infer the hierarchical relationships. The proposed method is assessed by simulation experiments of various settings and is applied to human brain data regarding schizophrenia. The MATLAB source codes are publicly available at: http://biomecis.uta.edu/epistasis. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. Quantum effects in biology: golden rule in enzymes, olfaction, photosynthesis and magnetodetection

    Science.gov (United States)

    Brookes, Jennifer C.

    2017-05-01

    Despite certain quantum concepts, such as superposition states, entanglement, `spooky action at a distance' and tunnelling through insulating walls, being somewhat counterintuitive, they are no doubt extremely useful constructs in theoretical and experimental physics. More uncertain, however, is whether or not these concepts are fundamental to biology and living processes. Of course, at the fundamental level all things are quantum, because all things are built from the quantized states and rules that govern atoms. But when does the quantum mechanical toolkit become the best tool for the job? This review looks at four areas of `quantum effects in biology'. These are biosystems that are very diverse in detail but possess some commonality. They are all (i) effects in biology: rates of a signal (or information) that can be calculated from a form of the `golden rule' and (ii) they are all protein-pigment (or ligand) complex systems. It is shown, beginning with the rate equation, that all these systems may contain some degree of quantumeffect, and where experimental evidence is available, it is explored to determine how the quantum analysis aids in understanding of the process.

  1. Biological Effects of Cloth Containing Specific Ore Powder in Patients with Pollen Allergy

    Institute of Scientific and Technical Information of China (English)

    Suni LEE; YasuzoKIRITA; YoshioFUJII; TakemiOTSUKI; HitoshiOKAMOTO; ShokoYAMAMOTO; TamayoHATAYAMA; HidenoriMATSUZAKI; Naoko KUMAGAI-TAKEI; KeiYOSHITOME; YasumitsuNISHIMURA; ToshiakiSATO

    2016-01-01

    ObjectiveThe custom-homebuilding company, Cosmic Garden Co. Ltd., located in Okayama City, Japan was established in 1997 and uses specific natural ore powder (SNOP) in wall materials and surveys customers in order to improve allergic symptoms. MethodsTo investigate the biological effects of SNOP, patients with a pollen allergy were recruited to stay in a room surrounded by cloth containing SNOP (CCSNOP), and their symptoms and various biological parameters were compared with those of individuals staying in a room surrounded by control non-woven cloth (NWC). Each stay lasted 60 min. Before and immediately after the stay, a questionnaire regarding allergic symptoms, as well as POMS (Profile of Mood Status) and blood sampling, was performed. Post-stay minus pre-stay values were calculated and compared between CCSNOP and NWC groups. ResultsResults indicated that some symptoms, such as nasal obstruction and lacrimation, improved, and POMS evaluation showed that patients were calmer following a stay in CCSNOP. Relative eosinophils, non-specific Ig E, epidermal growth factor, monocyte chemotactic protein-1, and tumor necrosis factor-α increased following a stay in CCSNOP. ConclusionThis ore powder improved allergic symptoms, and long-term monitoring involving 1 to 2 months may be necessary to fully explore the biological and physical effects of SNOP on allergic patients.

  2. High school teachers' perspectives on effective approaches for teaching biology to students with special needs

    Science.gov (United States)

    Kos, Agnieszka

    The demands of national educational reforms require high school biology teachers to provide high quality instruction to students with and without special needs. The reforms, however, do not provide teachers with adequate teaching strategies to meet the needs of all students in the same context. The purpose of this grounded theory study was to understand high school biology teachers' perspectives, practices, and challenges in relation to teaching students with special needs. This approach was used to develop a substantive model for high school biology teachers who are challenged with teaching students with and without special needs. Data were collected via in-depth interviews with 15 high school teachers in a Midwestern school district. The data were analyzed using open coding, axial coding, and selective coding procedures in accordance with the grounded theory approach. Essential model components included skills and training for teachers, classroom management strategies, teaching strategies, and student skills. The emergent substantive theory indicated that that teacher preparation and acquired skills greatly influence the effectiveness of inclusion implementation. Key findings also indicated the importance of using of a variety of instructional strategies and classroom management strategies that address students' special needs and their learning styles. This study contributes to social change by providing a model for teaching students and effectively implementing inclusion in regular science classrooms. Following further study, this model may be used to support teacher professional development and improve teaching practices that in turn may improve science literacy supported by the national educational reforms.

  3. The origin of neutron biological effectiveness as a function of energy

    Science.gov (United States)

    Baiocco, G.; Barbieri, S.; Babini, G.; Morini, J.; Alloni, D.; Friedland, W.; Kundrát, P.; Schmitt, E.; Puchalska, M.; Sihver, L.; Ottolenghi, A.

    2016-01-01

    The understanding of the impact of radiation quality in early and late responses of biological targets to ionizing radiation exposure necessarily grounds on the results of mechanistic studies starting from physical interactions. This is particularly true when, already at the physical stage, the radiation field is mixed, as it is the case for neutron exposure. Neutron Relative Biological Effectiveness (RBE) is energy dependent, maximal for energies ~1 MeV, varying significantly among different experiments. The aim of this work is to shed light on neutron biological effectiveness as a function of field characteristics, with a comprehensive modeling approach: this brings together transport calculations of neutrons through matter (with the code PHITS) and the predictive power of the biophysical track structure code PARTRAC in terms of DNA damage evaluation. Two different energy dependent neutron RBE models are proposed: the first is phenomenological and based only on the characterization of linear energy transfer on a microscopic scale; the second is purely ab-initio and based on the induction of complex DNA damage. Results for the two models are compared and found in good qualitative agreement with current standards for radiation protection factors, which are agreed upon on the basis of RBE data. PMID:27654349

  4. Cellular burdens and biological effects on tissue level caused by inhaled radon progenies

    CERN Document Server

    Madas, Balázs G; Farkas, Árpád; Szőke, István

    2014-01-01

    In the case of radon exposure, the spatial distribution of deposited radioactive particles is highly inhomogeneous in the central airways. The objective of this research is to investigate the consequences of this heterogeneity regarding cellular burdens in the bronchial epithelium and to study the possible biological effects on tissue level. Applying a computational fluid dynamics program, the deposition distribution of inhaled radon daughters has been determined in a bronchial airway model for 23 minutes of work in the New Mexico uranium mine corresponding to 0.0129 WLM exposure. A numerical epithelium model based on experimental data has been utilized in order to quantify cellular hits and doses. Finally, a carcinogenesis model considering cell death induced cell cycle shortening has been applied to assess the biological responses. Computations present, that cellular dose may reach 1.5 Gy, which is several orders of magnitude higher than tissue dose. The results are in agreement with the histological findin...

  5. The Biological Effects of Sex Hormones on Rabbit Articular Chondrocytes from Different Genders

    Directory of Open Access Journals (Sweden)

    Shwu Jen Chang

    2014-01-01

    Full Text Available The aim of this study was to investigate the biological effects of sex hormones (17β-estradiol and testosterone on rabbit articular chondrocytes from different genders. We cultured primary rabbit articular chondrocytes from both genders with varying concentration of sex hormones. We evaluate cell proliferation and biochemical functions by MTT and GAG assay. The chondrocyte function and phenotypes were analyzed by mRNA level using RT-PCR. Immunocytochemical staining was also used to evaluate the generation of collagen-II. This study demonstrated that 17β-estradiol had greater positive regulation on the biological function and gene expressions of articular chondrocytes than testosterone, with the optimal concentrations of 10−6 and 10−7 M, particularly for female chondrocytes.

  6. Biological effects of high strength electric fields. Second interim progress report, September 1976--March 1977

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, R.D.; Kaune, W.T.

    1977-05-01

    This report describes progress made on the Project during the period of September 9, 1976 to March 31, 1977 towards the determination of the biological effects of high strength electric fields on small laboratory animals. The efforts to date can be divided into five categories: (1) the design, construction, and testing of a prototype and special studies exposure system; (2) the design and construction of exposure systems for rats and mice; (3) dosimetry; (4) experiments to determine the maximum field strength which does not produce corona discharge, ozone formation, shocks to the animal, hair stimulation, or a behavioral preference by rats to avoid exposure to the field; and (5) preparations for the biological screening experiments.

  7. Biological Matrix Effects in Quantitative Tandem Mass Spectrometry-Based Analytical Methods: Advancing Biomonitoring

    Science.gov (United States)

    Panuwet, Parinya; Hunter, Ronald E.; D’Souza, Priya E.; Chen, Xianyu; Radford, Samantha A.; Cohen, Jordan R.; Marder, M. Elizabeth; Kartavenka, Kostya; Ryan, P. Barry; Barr, Dana Boyd

    2015-01-01

    The ability to quantify levels of target analytes in biological samples accurately and precisely, in biomonitoring, involves the use of highly sensitive and selective instrumentation such as tandem mass spectrometers and a thorough understanding of highly variable matrix effects. Typically, matrix effects are caused by co-eluting matrix components that alter the ionization of target analytes as well as the chromatographic response of target analytes, leading to reduced or increased sensitivity of the analysis. Thus, before the desired accuracy and precision standards of laboratory data are achieved, these effects must be characterized and controlled. Here we present our review and observations of matrix effects encountered during the validation and implementation of tandem mass spectrometry-based analytical methods. We also provide systematic, comprehensive laboratory strategies needed to control challenges posed by matrix effects in order to ensure delivery of the most accurate data for biomonitoring studies assessing exposure to environmental toxicants. PMID:25562585

  8. Across the Great Divide: The Effects of Technology in Secondary Biology Classrooms

    Science.gov (United States)

    Worley, Johnny Howard, II

    This study investigates the relationship between technology use and student achievement in public high school across North Carolina. The purpose of this study was to determine whether a digital divide (differences in technology utilization based on student demographics of race/ethnicity, gender, socioeconomic status, and municipality) exists among schools and whether those differences relate to student achievement in high school biology classrooms. The study uses North Carolina end-of-course (EOC) data for biology to analyze student demographic data and assessment results from the 2010-2011 school year from the North Carolina Department of Public Instruction. The data analyses use descriptive and factorial univariate statistics to determine the existence of digital divides and their effects on biology achievement. Analysis of these data described patterns of technology use to determine whether potential variances resulted in a digital divide. Specific technology uses were identified in the data and then their impact on biology achievement scores within various demographic groups was examined. Research findings revealed statistically significant variations of use within different population groups. Despite being statistically significant, the relevance of the association in the variations was minimal at best -- based on the effect scale established by Cohen (1988). Additional factorial univariate analyses were employed to determine potential relationships between technology use and student achievement. The data revealed that technology use did not influence the variation of student achievement scale scores as much as race/ethnicity and socioeconomic status. White students outperformed Hispanic students by an average of three scale score points and Black students by an average of six scale score points. Technology use alone averaged less than a one point difference in mean scale scores, and only when interacting with race, gender, and/or SES did the mean difference

  9. RANTES/CCL5 mediated-biological effects depend on the syndecan-4/PKCα signaling pathway

    Directory of Open Access Journals (Sweden)

    Loïc Maillard

    2014-09-01

    Full Text Available The perpetuation of angiogenesis is involved in certain chronic inflammatory diseases. The accelerated neovascularisation may result from an inflammatory status with a response of both endothelial cells and monocytes to inflammatory mediators such as chemokines. We have previously described in vitro and in vivo the pro-angiogenic effects of the chemokine Regulated on Activation, Normal T Cell Expressed and Secreted (RANTES/CCL5. The effects of RANTES/CCL5 may be related to its binding to G protein-coupled receptors and to proteoglycans such as syndecan-1 and -4. The aim of this study was to evaluate the functionality of syndecan-4 as a co-receptor of RANTES/CCL5 by the use of mutated syndecan-4 constructs. Our data demonstrate that site-directed mutations in syndecan-4 modify RANTES/CCL5 biological activities in endothelial cells. The SDC4S179A mutant, associated with an induced protein kinase C (PKCα activation, leads to higher RANTES/CCL5 pro-angiogenic effects, whereas the SDC4L188QQ and the SDC4A198del mutants, leading to lower phosphatidylinositol 4,5-bisphosphate (PIP2 binding or to lower PDZ protein binding respectively, are associated with reduced RANTES/CCL5 cellular effects. Moreover, our data highlight that the intracellular domain of SDC-4 is involved in RANTES/CCL5-induced activation of the PKCα signaling pathway and biological effect. As RANTES/CCL5 is involved in various physiopathological processes, the development of a new therapeutic strategy may be reliant on the mechanism by which RANTES/CCL5 exerts its biological activities, for example by targeting the binding of the chemokine to its proteoglycan receptor.

  10. Effect of capping agents: Structural, optical and biological properties of ZnO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Javed, Rabia [Department of Biotechnology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Usman, Muhammad, E-mail: uk_phy@yahoo.com [Department of Physics, Faculty of Natural Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Department of Physics, School of Science and Engineering, Lahore University of Management Sciences, Lahore 54729 (Pakistan); Tabassum, Saira; Zia, Muhammad [Department of Biotechnology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan)

    2016-11-15

    Highlights: • ZnO nanoparticles have been effectively capped with polyethylene glycol (PEG) and polyvinyl pyrrolidone (PVP) shown by the data of XRD, FTIR and UV–visible spectroscopy. • Reduction in size occurred from 34 nm to 26 nm due to capping agent and band gap energy increases with the decrease in the particle size. • Antibacterial activity against Gram-positive bacteria is greater than the Gram-negative bacteria. • All biological assays reveal highest activities in capped ZnO nanoparticles as compared to the uncapped ZnO nanoparticles. • Highest antibacterial activity has been exhibited by ZnO-PVP while highest antioxidant and antidiabetic activities have been conferred by ZnO- PEG. - Abstract: Different biological activities of capped and uncapped ZnO nanoparticles were investigated, and the effects of potential capping agents on these biological activities were studied. ZnO nanoparticles were synthesized and capped by polyethylene glycol (PEG) and polyvinyl pyrrolidone (PVP) using a simple chemical method of co-precipitation. Characterization by X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR) and UV–vis spectroscopy confirmed the crystallinity, size, functional group, and band gap of synthesized nanoparticles. Reduction in size occurred from 34 nm to 26 nm due to surfactant. Results of all biological activities indicated significantly higher values in capped as compared to uncapped nanoparticles. Antibacterial activity against Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633), Escherichia coli (ATCC15224), and Acetobacter was obtained. This activity was more prominent against Gram-positive bacteria, and ZnO-PVP nanoparticles elucidated highest antibacterial activity (zone of inhibition 17 mm) against Gram-positive, Bacillus subtilis species. Antioxidant activities including total flavonoid content, total phenolic content, total antioxidant capacity, total reducing power and %age inhibition of DPPH, and

  11. Heavy-ion radiobiology: new approaches to delineate mechanisms underlying enhanced biological effectiveness.

    Science.gov (United States)

    Blakely, E A; Kronenberg, A

    1998-11-01

    Shortly after the discovery of polonium and radium by Marie Curie and her husband and colleague, Pierre Curie, it was learned that exposure to these alpha-particle emitters produced deleterious biological effects. The mechanisms underlying the increased biological effectiveness of densely ionizing radiations, including alpha particles, neutrons and highly energetic heavy charged particles, remain an active area of investigation. In this paper, we review recent advances in several areas of the radiobiology of these densely ionizing radiations, also known as heavy ions. Advances are described in the areas of DNA damage and repair, chromosome aberrations, mutagenesis, neoplastic transformation in vitro, genomic instability, normal tissue radiobiology and carcinogenesis in vivo. We focus on technical innovations, including novel applications of pulsed-field gel electrophoresis, fluorescence in situ hybridization (FISH), linkage analysis, and studies of gene expression and protein expression. We also highlight the use of new cellular and animal systems, including those with defined DNA repair deficiencies, as well as epithelial cell model systems to assess neoplastic transformation both in vitro and in vivo. The studies reviewed herein have had a substantial impact on our understanding of the genotoxic effects of heavy ions as well as their distinct effects on tissue homeostasis. The use of these radiations in cancer therapy is also discussed. The use of both heavy-ion and proton therapy is on the upswing in several centers around the world, due to their unique energy deposition characteristics that enhance the therapeutic effect and help reduce damage to normal tissue.

  12. Heavy-ion radiobiology: new approaches to delineate mechanisms underlying enhanced biological effectiveness

    Science.gov (United States)

    Blakely, E. A.; Kronenberg, A.; Chatterjee, A. (Principal Investigator)

    1998-01-01

    Shortly after the discovery of polonium and radium by Marie Curie and her husband and colleague, Pierre Curie, it was learned that exposure to these alpha-particle emitters produced deleterious biological effects. The mechanisms underlying the increased biological effectiveness of densely ionizing radiations, including alpha particles, neutrons and highly energetic heavy charged particles, remain an active area of investigation. In this paper, we review recent advances in several areas of the radiobiology of these densely ionizing radiations, also known as heavy ions. Advances are described in the areas of DNA damage and repair, chromosome aberrations, mutagenesis, neoplastic transformation in vitro, genomic instability, normal tissue radiobiology and carcinogenesis in vivo. We focus on technical innovations, including novel applications of pulsed-field gel electrophoresis, fluorescence in situ hybridization (FISH), linkage analysis, and studies of gene expression and protein expression. We also highlight the use of new cellular and animal systems, including those with defined DNA repair deficiencies, as well as epithelial cell model systems to assess neoplastic transformation both in vitro and in vivo. The studies reviewed herein have had a substantial impact on our understanding of the genotoxic effects of heavy ions as well as their distinct effects on tissue homeostasis. The use of these radiations in cancer therapy is also discussed. The use of both heavy-ion and proton therapy is on the upswing in several centers around the world, due to their unique energy deposition characteristics that enhance the therapeutic effect and help reduce damage to normal tissue.

  13. Leishmania tropica: the effect of darkness and light on biological activities in vitro.

    Science.gov (United States)

    Allahverdiyev, Adil M; Koc, Rabia Cakir; Ates, Sezen Canim; Bagirova, Malahat; Elcicek, Serhat; Oztel, Olga Nehir

    2011-08-01

    Leishmania parasites can be exposed to effects of light in their vectors and hosts, at various periods. However, there is no information about the effects of light on Leishmania parasites. The aim of this study is to investigate the effects of light on various cell parameters of Leishmania tropica, in vitro. All experiments were conducted on L. tropica promastigotes and amastigote-macrophage cultures, using flow cytometric analysis, MTT and phenol-sulfuric acid assay, DAPI and Giemsa. The results showed that the morphology of parasites has changed; the cell cycle has been affected and this caused parasites to remain at G0/G1 phase. Furthermore the proliferation, infectivity, glucose consumption and mitochondrial dehydrogenase activities of parasites were decreased. Thus, for the first time, in this study, the effects of light on biological activities of Leishmania parasites were shown. These new information about parasites' biology, would be very important to investigate the effects of light on the parasites in infected vectors and hosts.

  14. Track Structure and the Biological Effectiveness of Accelerated Particles for the Induction of Chromosome Damage

    Science.gov (United States)

    George, K.; Hada, M.; Chappell, L.; Cucinotta, F. A.

    2011-01-01

    Track structure models predict that at a fixed value of LET, particles with lower charge number, Z will have a higher biological effectiveness compared to particles with a higher Z. In this report we investigated how track structure effects induction of chromosomal aberration in human cells. Human lymphocytes were irradiated in vitro with various energies of accelerated iron, silicon, neon, or titanium ions and chromosome damage was assessed in using three color FISH chromosome painting in chemically induced PCC samples collected a first cell division post irradiation. The LET values for these ions ranged from 30 to195 keV/micron. Of the particles studied, Neon ions have the highest biological effectiveness for induction of total chromosome damage, which is consistent with track structure model predictions. For complex-type exchanges 64 MeV/ u Neon and 450 MeV/u Iron were equally effective and induced the most complex damage. In addition we present data on chromosomes exchanges induced by six different energies of protons (5 MeV/u to 2.5 GeV/u). The linear dose response term was similar for all energies of protons suggesting that the effect of the higher LET at low proton energies is balanced by the production of nuclear secondaries from the high energy protons.

  15. The Effects of Using Concept Mapping for Improving Advanced Level Biology Students' Lower- and Higher-Order Cognitive Skills

    Science.gov (United States)

    Bramwell-Lalor, Sharon; Rainford, Marcia

    2014-01-01

    This paper reports on teachers' use of concept mapping as an alternative assessment strategy in advanced level biology classes and its effects on students' cognitive skills on selected biology concepts. Using a mixed methods approach, the study employed a pre-test/post-test quasi-experimental design involving 156 students and 8 teachers from…

  16. Biological monitoring of non-thermal effects of mobile phone radiation: recent approaches and challenges.

    Science.gov (United States)

    Gaestel, Matthias

    2010-08-01

    This review describes recent developments in analysing the influence of radio-frequency electromagnetic fields (RF-EMFs ) on biological systems by monitoring the cellular stress response as well as overall gene expression. Recent data on the initiation and modulation of the classical cellular stress response by RF-EMFs, comprising expression of heat shock proteins and stimulation of stress-activated protein kinases, are summarised and evaluated. Since isothermic RF-EMF exposure is assumed rather than proven there are clear limitations in using the stress response to describe non-thermal effects of RF-EMFs. In particular, further experiments are needed to characterise better the threshold of the thermal heat shock response and the homogeneity of the cellular response in the whole sample for each biological system used. Before then, it is proposed that the absence of the classical stress response can define isothermal experimental conditions and qualifies other biological effects of RF-EMFs detected under these conditions to be of non-thermal origin. To minimise the probability that by making this assumption valuable insights into the nature of biological effects of RF-EMFs could be lost, proteotoxic non-thermal RF-EMF effects should also be monitored by measuring activities of labile intracellular enzymes and/or levels of their metabolites before the threshold for the heat shock response is reached. In addition, non-thermal induction of the stress response via promoter elements distinct from the heat shock element (HSE) should be analysed using HSE-mutated heat shock promoter reporter constructs. Screening for non-thermal RF-EMF effects in the absence of a classical stress response should be performed by transcriptomics and proteomics. Recent approaches demonstrate that due to their high-throughput characteristics, these methods inherently generate false positive results and require statistical evaluation based on quantitative expression analysis from a sufficient

  17. Effective automated feature construction and selection for classification of biological sequences.

    Directory of Open Access Journals (Sweden)

    Uday Kamath

    Full Text Available Many open problems in bioinformatics involve elucidating underlying functional signals in biological sequences. DNA sequences, in particular, are characterized by rich architectures in which functional signals are increasingly found to combine local and distal interactions at the nucleotide level. Problems of interest include detection of regulatory regions, splice sites, exons, hypersensitive sites, and more. These problems naturally lend themselves to formulation as classification problems in machine learning. When classification is based on features extracted from the sequences under investigation, success is critically dependent on the chosen set of features.We present an algorithmic framework (EFFECT for automated detection of functional signals in biological sequences. We focus here on classification problems involving DNA sequences which state-of-the-art work in machine learning shows to be challenging and involve complex combinations of local and distal features. EFFECT uses a two-stage process to first construct a set of candidate sequence-based features and then select a most effective subset for the classification task at hand. Both stages make heavy use of evolutionary algorithms to efficiently guide the search towards informative features capable of discriminating between sequences that contain a particular functional signal and those that do not.To demonstrate its generality, EFFECT is applied to three separate problems of importance in DNA research: the recognition of hypersensitive sites, splice sites, and ALU sites. Comparisons with state-of-the-art algorithms show that the framework is both general and powerful. In addition, a detailed analysis of the constructed features shows that they contain valuable biological information about DNA architecture, allowing biologists and other researchers to directly inspect the features and potentially use the insights obtained to assist wet-laboratory studies on retainment or modification

  18. Combined exposures: an update from the International Commission on Biological Effects of Noise.

    Science.gov (United States)

    Leroux, Tony; Klaeboe, Ronny

    2012-01-01

    International Commission on Biological Effects of Noise (ICBEN) Team 8 deals with the effects of combined "agents" in the urban and work place settings. Results presented at the ICBEN conference indicate that some pesticides, more specifically the organophosphates, and a wider range of industrial chemicals are harmful to the auditory system at concentrations often found in occupational settings. Effects of occupational noise on hearing are exacerbated by toluene and possibly by carbon monoxide. Several of the chemicals studied found to be potentially toxic not only to hair cells in the cochlea but also to the auditory nerve. In urban environments, team 8 focuses on additive and synergetic effects of ambient stressors. It was argued that noise policies need to pay attention to grey areas with intermediate noise levels. Noteworthy is also stronger reactions to vibrations experienced in the evening and during the night. An innovative event-based model for sound perception was presented.

  19. Assessment of the biological effects of 'strange' radiation

    Energy Technology Data Exchange (ETDEWEB)

    Pryakhin, E.A.; Tryapitsina, G.A. [Chelyabinsk State University, Chelyabinsk (Russian Federation); Urutskoyev, L.I. [RECOM Company, Kurchatov Russian Research Institute, Moscow (Russian Federation); Akleyev, A.V. [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation)

    2006-07-01

    The results from studies of the effects produced by electrical explosions of foils made from super pure materials in water point to the emergence of new chemical elements. An additional finding was the discharge of 'strange' radiation accompanying the transformation of chemical elements. However, currently, the mechanism involved in the interaction between 'strange' radiation and a substance or a biological entity remains obscure. Therefore, the aim of the present research is to investigate the biological effects of the 'strange' radiation. Pilot studies were performed at the RECOM RRC 'Kurchatov Institute' in April-May of 2004. The animals used in the experiment were female mice of C57Bl/6 line aged 80 days with body weight 16-18 g. The animals were exposed to radiation discharged during explosions of Ti foils in water and aqueous solutions. The cages with animals were placed at 1 m from the epicenter of the explosion. Explosions were carried out on the 19. (3 explosions), 20. (4 explosions) and 22. (3 explosions) of April, 2004 (explosions No1373 - No1382, respectively). The animals were assigned to 4 experimental groups comprised of 17-20 mice per group. The animals received experimental exposure within 1, 2 and 3 days of the experiment. In total, the experimental groups were exposed to 3, 7 and 10 explosions, respectively. In order to identify the biological reactions, the following parameters were estimated: number of nucleated cells in the bone marrow, number of CFU in the spleen after additional gamma-irradiation (6 Gy), cell composition of the bone marrow, the rate of erythrocytes with the different level of maturation in the bone marrow, the rate of erythrocytes with the micronuclei in the bone marrow, the reaction of bone marrow cells to additional gamma-irradiation (2 Gy), number of leucocytes in the peripheral blood, and cell composition of the peripheral blood. The following conclusions were drawn from these

  20. Biological therapies (immunomodulatory drugs), worsening of psoriasis and rebound effect: new evidence of similitude.

    Science.gov (United States)

    Teixeira, Marcus Zulian

    2016-11-01

    Employing the secondary action or adaptative reaction of the organism as therapeutic response, homeopathy uses the treatment by similitude (similia similibus curentur) administering to sick individuals the medicines that caused similar symptoms in healthy individuals. Such homeostatic or paradoxical reaction of the organism is scientifically explained through the rebound effect of drugs, which cause worsening of symptoms after withdrawal of several palliative treatments. Despite promoting an improvement in psoriasis at the beginning of the treatment, modern biological therapies provoke worsening of the psoriasis (rebound psoriasis) after discontinuation of drugs. Exploratory qualitative review of the literature on the occurrence of the rebound effect with the use of immunomodulatory drugs [T-cell modulating agents and tumor necrosis factor (TNF) inhibitors drugs] in the treatment of psoriasis. Several researches indicate the rebound effect as the mechanism of worsening of psoriasis with the use of efalizumab causing the suspension of its marketing authorization in 2009, in view of some severe cases. Other studies also have demonstrated the occurrence of rebound psoriasis with the use of alefacept, etanercept and infliximab. As well as studied in other classes of drugs, the rebound effect of biologic agents supports the principle of similitude (primary action of the drugs followed by secondary action and opposite of the organism). Copyright © 2016 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

  1. [EFFECT OF MICROSYMBIONTS ON THE ABILITY OF VAGINAL EPITHELIOCYTES TO MODIFY BIOLOGICAL PROPERTIES OF BACTERIA].

    Science.gov (United States)

    Kremleva, E A; Sgibnev, A V; Cherkasov, S V

    2015-01-01

    Study regularities of effects of various types of vaginal microsymbionts on the ability of mucosal epitheliocytes of the vagina to modify biological properties of bacteria. Effect of thermo-inactivated cells of Staphylococcus aureus, Escherichia coli, H2O2-producing and H2O2-non-producing lactobacilli on the ability of primary vaginal epitheliocytes to alter growth and antagonistic activity of Staphylococcus aureus, Escherichia colt, H2O2-producing and H2O2-nonproducing lactobacilli was studied using a multi-component module system. Alterations of composition of vaginal epitlieliocyte exometabolites under the effect of S. aureus and E. coli was established to result in a pronounced stimulation of antagonistic activity of H2O2-producing and an increase of the number of H2O2-nonproducing lactobacilli. Thermo-inactivated cells of lactobacilli stimulated production of metabolites by epitheliocytes, that suppress the growth and antagonistic activity of allochthonous microflora and stimulate similar parameters of lactobacilli. The strongest effects on the ability of vaginal epitheliocytes to alter biological properties of bacteria were rendered by H2O2-producing lactobacilli. The regularities identified allow to examine epitheliocytes and normoflora of vagina as a symbiotic system, the coordinated interaction of its components is directed on maintaining microecological stability of female reproductive tract.

  2. Relative Biological Effectiveness of HZE Particles for Chromosomal Exchanges and Other Surrogate Cancer Risk Endpoints

    Science.gov (United States)

    Cacao, Eliedonna; Hada, Megumi; Saganti, Premkumar B.; George, Kerry A.; Cucinotta, Francis A.

    2016-01-01

    The biological effects of high charge and energy (HZE) particle exposures are of interest in space radiation protection of astronauts and cosmonauts, and estimating secondary cancer risks for patients undergoing Hadron therapy for primary cancers. The large number of particles types and energies that makeup primary or secondary radiation in HZE particle exposures precludes tumor induction studies in animal models for all but a few particle types and energies, thus leading to the use of surrogate endpoints to investigate the details of the radiation quality dependence of relative biological effectiveness (RBE) factors. In this report we make detailed RBE predictions of the charge number and energy dependence of RBE’s using a parametric track structure model to represent experimental results for the low dose response for chromosomal exchanges in normal human lymphocyte and fibroblast cells with comparison to published data for neoplastic transformation and gene mutation. RBE’s are evaluated against acute doses of γ-rays for doses near 1 Gy. Models that assume linear or non-targeted effects at low dose are considered. Modest values of RBE (10) are predicted at low doses <0.1 Gy. The radiation quality dependence of RBE’s against the effects of acute doses γ-rays found for neoplastic transformation and gene mutation studies are similar to those found for simple exchanges if a linear response is assumed at low HZE particle doses. Comparisons of the resulting model parameters to those used in the NASA radiation quality factor function are discussed. PMID:27111667

  3. Relative Biological Effectiveness of HZE Particles for Chromosomal Exchanges and Other Surrogate Cancer Risk Endpoints.

    Directory of Open Access Journals (Sweden)

    Eliedonna Cacao

    Full Text Available The biological effects of high charge and energy (HZE particle exposures are of interest in space radiation protection of astronauts and cosmonauts, and estimating secondary cancer risks for patients undergoing Hadron therapy for primary cancers. The large number of particles types and energies that makeup primary or secondary radiation in HZE particle exposures precludes tumor induction studies in animal models for all but a few particle types and energies, thus leading to the use of surrogate endpoints to investigate the details of the radiation quality dependence of relative biological effectiveness (RBE factors. In this report we make detailed RBE predictions of the charge number and energy dependence of RBE's using a parametric track structure model to represent experimental results for the low dose response for chromosomal exchanges in normal human lymphocyte and fibroblast cells with comparison to published data for neoplastic transformation and gene mutation. RBE's are evaluated against acute doses of γ-rays for doses near 1 Gy. Models that assume linear or non-targeted effects at low dose are considered. Modest values of RBE (10 are predicted at low doses <0.1 Gy. The radiation quality dependence of RBE's against the effects of acute doses γ-rays found for neoplastic transformation and gene mutation studies are similar to those found for simple exchanges if a linear response is assumed at low HZE particle doses. Comparisons of the resulting model parameters to those used in the NASA radiation quality factor function are discussed.

  4. Comparison of ethanol, methanol and succinate effects as carbon sources on effluent biological denitrification

    Directory of Open Access Journals (Sweden)

    abbas Rezaee

    2008-04-01

    Full Text Available Abstract Background: Increase of nitrate concentration in water sources is becoming a serious problem in many parts of the world. Nitrogen containing compounds released into environment can create serious problems, such as eutrophication of water sources and hazard potential to human health, because it has potency of causing methemoglubinemia disease and cancer. Between recommended methods, biological denitrification is an effective method to remove nitrate from water and wastewater. Materials and methods: In this study, biological nitrogen removal process was evaluated using ethanol, methanol and succinate as different organic carbon sources in batch scale. The different parameters, carbon source, initial nitrate concentration, pH, and inoculated of bacteria were evaluated. Results: The experimental results were showed that bacteria can not use methanol as carbon source. The dinitrifyers bacteria can dissimilate 200 mg/L No3-N, in the optimum condition: 28 ºC, pH 7.2 and initial inoculation of 3×108 CFU/ml, respectively. In the process, produced nitrate-N was less than 1 mg/l. Conclusion: The bacterium Pseudomonas stutzeri can use ethanol as carbon source for biological denitrification, but efficiency of succinate was better than ethanol.

  5. Effect of capping agents: Structural, optical and biological properties of ZnO nanoparticles

    Science.gov (United States)

    Javed, Rabia; Usman, Muhammad; Tabassum, Saira; Zia, Muhammad

    2016-11-01

    Different biological activities of capped and uncapped ZnO nanoparticles were investigated, and the effects of potential capping agents on these biological activities were studied. ZnO nanoparticles were synthesized and capped by polyethylene glycol (PEG) and polyvinyl pyrrolidone (PVP) using a simple chemical method of co-precipitation. Characterization by X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR) and UV-vis spectroscopy confirmed the crystallinity, size, functional group, and band gap of synthesized nanoparticles. Reduction in size occurred from 34 nm to 26 nm due to surfactant. Results of all biological activities indicated significantly higher values in capped as compared to uncapped nanoparticles. Antibacterial activity against Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633), Escherichia coli (ATCC15224), and Acetobacter was obtained. This activity was more prominent against Gram-positive bacteria, and ZnO-PVP nanoparticles elucidated highest antibacterial activity (zone of inhibition 17 mm) against Gram-positive, Bacillus subtilis species. Antioxidant activities including total flavonoid content, total phenolic content, total antioxidant capacity, total reducing power and %age inhibition of DPPH, and antidiabetic activity against α-amylase enzyme found to be exhibited highest by ZnO-PEG nanoparticles.

  6. Protective Effect of Selected Medicinal Plants against Hydrogen Peroxide Induced Oxidative Damage on Biological Substrates

    Directory of Open Access Journals (Sweden)

    Namratha Pai Kotebagilu

    2014-01-01

    Full Text Available Oxidative stress is developed due to susceptibility of biological substrates to oxidation by generation of free radicals. In degenerative diseases, oxidative stress level can be reduced by antioxidants which neutralize free radicals. Primary objective of this work was to screen four medicinal plants, namely, Andrographis paniculata, Costus speciosus, Canthium parviflorum, and Abrus precatorius, for their antioxidant property using two biological substrates—RBC and microsomes. The antioxidative ability of three solvent extracts, methanol (100% and 80% and aqueous leaf extracts, was studied at different concentrations by thiobarbituric acid reactive substances method using Fenton’s reagent to induce oxidation in the substrates. The polyphenol and flavonoid content were analyzed to relate with the observed antioxidant effect of the extracts. The phytochemical screening indicated the presence of flavonoids, polyphenols, tannins, and β-carotene in the samples. In microsomes, 80% methanol extract of Canthium and Costus and, in RBC, 80% methanol extract of Costus showed highest inhibition of oxidation and correlated well with the polyphenol and flavonoid content. From the results it can be concluded that antioxidants from medicinal plants are capable of inhibiting oxidation in biological systems, suggesting scope for their use as nutraceuticals.

  7. Effects of gentle remediation technologies on soil biological and biochemical activities - a review.

    Science.gov (United States)

    Marschner, B.; Haag, R.; Renella, G.

    2009-04-01

    Remediation technologies for contaminated sites are generally designed to reduce risks for human health, groundwater or plant quality. While some drastic remediation measures such as soil excavation, thermal treatment or soil washing eliminate or strongly reduce soil life, in-situ treatments involving plants or immobilizing additives may also restore soil functionality by establishing or promoting a well structured and active community of soil organisms. Biological parameters that are sensitive to contaminants and other pedo-environmental conditions and which contribute to biogeochemical nutrient cycles, can be used as synthetic indicators of the progress and also the efficiency of given remediation approaches. Data from long-term studies on re-vegetated mine spoils show that biological and biochemical activity is enhanced with increasing plant density and diversity. Among the soil amendments, most measures that introduce organic matter or alkalinity to the contaminated soils also improve microbial or faunal parameters. Only few amendments, such as phosphates and chelators have deleterious effects on soil biota. In this review, soil microbial biomass and the activity of the enzymes phosphatase and arylsulphatase are identified as suitable and sensitive biological indicators for soil health. The results and future research needs are are summarized.

  8. Leukemia, an effective model for chemical biology and target therapy1

    Institute of Scientific and Technical Information of China (English)

    Guo-qiang CHEN; Li-shun WANG; Ying-li WU; Yun YU

    2007-01-01

    The rapid rise of chemical biology aimed at studying signaling networks for basic cellular activities using specific, active small molecules as probes has greatly accelerated research on pathological mechanisms and target therapy of diseases.This research is especially important for malignant tumors such as leukemia, a heterogeneous group of hematopoietic malignancies that occurs worldwide. With the use of a chemical approach combined with genetic manipulation, great progresshas been achieved over the past few decades on the biological, molecular and cytogenetic aspects of leukemia, and in its diagnosis and therapy. In particular,discoveries of the clinical effectiveness of all-trans rctinoic acid and arsenic trioxide in the treatment of acute promyelocytic leukemia and the kinase inhibitorsImatinib and Dasatinib in the treatment of chronic myelogenous leukemia not only make target therapy of leukemia a reality, but also push mechanisms of leukemo-genesis and leukemic cell activities forward. This review will outline advances in chemical biology that help our understanding of the molecular mechanisms of cell differentiation and apoptosis induction and target therapy of leukemia.

  9. The effect of teaching methods on cognitive achievement, retention, and attitude among in biology studying

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    Snezana Stavrova Veselinovskaa

    2011-12-01

    Full Text Available The purpose of this paper is to determine the effects of usage of sequential teaching method on the academic achievement and retention level of students. Three student groups of biology students in University “Goce Delcev”, Faculty of Natural and Technical Sciences, Institute of Biology, - Stip, R. Macedonia were offered a topic on general characteristics of Proteins: Their Biological Functions and Primary Structure with different sequences of 3 teaching methods. The teaching methods were Laboratory method (student experiment, slide demonstration and lecture method. The first group started to course with experiments in the laboratory, then the relevant theory of proteins was given lecture method, and then the slides was shown (Group I. The sequence of these three teaching methods used in the first group was changed in both second and third group as follow: The lecture methods, slide show and experiment in Group II, and slide show, experiment and lecture method in Group III, respectively. Laboratory method used in the study was focused on the topic of this diversity and abundance reflect the central role of proteins in virtually all aspects of cell structure and function. Achievement test contained 20 questions, testing the knowledge of facts as well as the ability to transfer the knowledge and problem solving ability. This test was used as pre-test before methods’ application, post-test after the methods’ application and retention test after 30 days from methods’ applied.

  10. Physico-chemical properties and biological effects of diesel and biomass particles.

    Science.gov (United States)

    Longhin, Eleonora; Gualtieri, Maurizio; Capasso, Laura; Bengalli, Rossella; Mollerup, Steen; Holme, Jørn A; Øvrevik, Johan; Casadei, Simone; Di Benedetto, Cristiano; Parenti, Paolo; Camatini, Marina

    2016-08-01

    Diesel combustion and solid biomass burning are the major sources of ultrafine particles (UFP) in urbanized areas. Cardiovascular and pulmonary diseases, including lung cancer, are possible outcomes of combustion particles exposure, but differences in particles properties seem to influence their biological effects. Here the physico-chemical properties and biological effects of diesel and biomass particles, produced under controlled laboratory conditions, have been characterized. Diesel UFP were sampled from a Euro 4 light duty vehicle without DPF fuelled by commercial diesel and run over a chassis dyno. Biomass UFP were collected from a modern automatic 25 kW boiler propelled by prime quality spruce pellet. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images of both diesel and biomass samples showed aggregates of soot particles, but in biomass samples ash particles were also present. Chemical characterization showed that metals and PAHs total content was higher in diesel samples compared to biomass ones. Human bronchial epithelial (HBEC3) cells were exposed to particles for up to 2 weeks. Changes in the expression of genes involved in xenobiotic metabolism were observed after exposure to both UFP already after 24 h. However, only diesel particles modulated the expression of genes involved in inflammation, oxidative stress and epithelial-to-mesenchymal transition (EMT), increased the release of inflammatory mediators and caused phenotypical alterations, mostly after two weeks of exposure. These results show that diesel UFP affected cellular processes involved in lung and cardiovascular diseases and cancer. Biomass particles exerted low biological activity compared to diesel UFP. This evidence emphasizes that the study of different emission sources contribution to ambient PM toxicity may have a fundamental role in the development of more effective strategies for air quality improvement.

  11. Physico-chemical properties and biological effects of diesel and biomass particles

    KAUST Repository

    Longhin, Eleonora

    2016-05-15

    © 2016 Elsevier Ltd. Diesel combustion and solid biomass burning are the major sources of ultrafine particles (UFP) in urbanized areas. Cardiovascular and pulmonary diseases, including lung cancer, are possible outcomes of combustion particles exposure, but differences in particles properties seem to influence their biological effects.Here the physico-chemical properties and biological effects of diesel and biomass particles, produced under controlled laboratory conditions, have been characterized. Diesel UFP were sampled from a Euro 4 light duty vehicle without DPF fuelled by commercial diesel and run over a chassis dyno. Biomass UFP were collected from a modern automatic 25 kW boiler propelled by prime quality spruce pellet. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images of both diesel and biomass samples showed aggregates of soot particles, but in biomass samples ash particles were also present. Chemical characterization showed that metals and PAHs total content was higher in diesel samples compared to biomass ones.Human bronchial epithelial (HBEC3) cells were exposed to particles for up to 2 weeks. Changes in the expression of genes involved in xenobiotic metabolism were observed after exposure to both UFP already after 24 h. However, only diesel particles modulated the expression of genes involved in inflammation, oxidative stress and epithelial-to-mesenchymal transition (EMT), increased the release of inflammatory mediators and caused phenotypical alterations, mostly after two weeks of exposure.These results show that diesel UFP affected cellular processes involved in lung and cardiovascular diseases and cancer. Biomass particles exerted low biological activity compared to diesel UFP. This evidence emphasizes that the study of different emission sources contribution to ambient PM toxicity may have a fundamental role in the development of more effective strategies for air quality improvement.

  12. Effect of iron oxide and gold nanoparticles on bacterial growth leading towards biological application

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    Bandyopadhyay Arghya

    2011-08-01

    Full Text Available Abstract Background Nanoparticle-metal oxide and gold represents a new class of important materials that are increasingly being developed for use in research and health related activities. The biological system being extremely critical requires the fundamental understanding on the influence of inorganic nanoparticles on cellular growth and functions. Our study was aimed to find out the effect of iron oxide (Fe3O4, gold (Au nanoparticles on cellular growth of Escherichia coli (E. coli and also try to channelize the obtained result by functionalizing the Au nanoparticle for further biological applications. Result Fe3O4 and Au nanoparticles were prepared and characterized using Transmission electron microscopy (TEM and Dynamic Light Scattering (DLS. Preliminary growth analysis data suggest that the nanoparticles of iron oxide have an inhibitory effect on E. coli in a concentration dependant manner, whereas the gold nanoparticle directly showed no such activity. However the phase contrast microscopic study clearly demonstrated that the effect of both Fe3O4 and Au nanoparticle extended up to the level of cell division which was evident as the abrupt increase in bacterial cell length. The incorporation of gold nanoparticle by bacterial cell was also observed during microscopic analysis based on which glutathione functionalized gold nanoparticle was prepared and used as a vector for plasmid DNA transport within bacterial cell. Conclusion Altogether the study suggests that there is metal nanoparticle-bacteria interaction at the cellular level that can be utilized for beneficial biological application but significantly it also posses potential to produce ecotoxicity, challenging the ecofriendly nature of nano