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Sample records for bio dosemeters hsp

  1. HSP as bio dosemeters

    International Nuclear Information System (INIS)

    Manzanares A, E.; Vega C, H.R.

    2005-01-01

    A review of the more important passages for the field of the radiological protection, from the discovery, beginnings of the utilization of the radiations emitting, passing to the legislation proposals and the transformations that had been suffer to establish the international standards of radiological protection. The paradigms on the effects and chronologically the emanated discoveries of the cellular research and the measurement of cellular products in the species and the diverse alive beings making emphasis in evaluating the expression of the heat-shock proteins caused by low doses of gamma radiation, these are used as radiation bio monitors and of other agents that cause cellular stress and lastly a prospective of the future of the radiobiology. (Author)

  2. HSP as bio dosemeters; HSP como biodosimetros

    Energy Technology Data Exchange (ETDEWEB)

    Manzanares A, E; Vega C, H R [Grupo Academico de Radiobiologia, UAZ, A.P. 336, 98000 Zacatecas (Mexico)

    2005-07-01

    A review of the more important passages for the field of the radiological protection, from the discovery, beginnings of the utilization of the radiations emitting, passing to the legislation proposals and the transformations that had been suffer to establish the international standards of radiological protection. The paradigms on the effects and chronologically the emanated discoveries of the cellular research and the measurement of cellular products in the species and the diverse alive beings making emphasis in evaluating the expression of the heat-shock proteins caused by low doses of gamma radiation, these are used as radiation bio monitors and of other agents that cause cellular stress and lastly a prospective of the future of the radiobiology. (Author)

  3. Electronic personal dosemeters

    International Nuclear Information System (INIS)

    Marshall, T.O.; Bartlett, D.T.; Burgess, P.H.; Cranston, C.S.; Higginbottom, D.J.; Sutton, K.W.

    1990-01-01

    Personal dosimetry services approved by their national authorities for category A workers, invariably use passive dosemeters incorporating photographic film or thermoluminescent detectors. However, the performance characteristics of electronic dosemeters has improved substantially over the past decade to such an extent that in the opening lecture of the Solid State Dosimetry Conference at Oxford in 1986 the development of an electronic 'smart card' based on a silicon detector was briefly discussed. This idea has been taken up and at least one development programme is in progress aimed at the production of an electronic dosemeter suitable for use as a legal device. The more important performance requirements of personal dosemeters for this purpose are discussed and the earlier electronic dosemeter designs and the latest devices under development to meet this specification are compared. (author)

  4. Comparison test of electronic dosemeters

    International Nuclear Information System (INIS)

    Butterweck, G.; Zimmerli, H.P.; Wernli, C.

    2001-01-01

    To assist with a planned purchase of electronic dosemeters by the Swiss Federal Office for Civil Protection, the calibration laboratory of the Paul Scherrer Institute performed tests on 11 types of electronic dosemeters manufactured by 10 European and American companies. The technical specifications for the World Trade Organisation (WTO) tendering procedure were largely in accord with the specifications of the international standard IEC 61526. First tests were performed with samples from each type of dosemeter. The reproducibility of a dose of 0.1 mSv generated with 137 Cs radiation at a dose rate of 2.1 mSv.h -1 was found adequate for all tested dosemeter types. The response for environmental levels of radiation showed a large variation, indicating insufficient background correction of some dosemeters. A very high dose rate of 10 Sv.h -1 provoked faulty dose readings for more than half of the tested dosemeters. Dosemeter response for low-energy photon radiation was satisfactory for two of the tested dosemeter types. Four dosemeter types were selected for extended technical tests. Three samples of each of these dosemeter types were purchased. For drop and temperature tests the specifications of the WTO tendering procedure outranged the specification of the IEC standard. Whereas even at a temperature of -25 deg. C the tested dosemeters functioned normally, drops from a height of 2 m onto a wooden surface rendered the samples of two dosemeter types inoperative. (author)

  5. Acid dip for dosemeter

    International Nuclear Information System (INIS)

    Stewart, J.C.; McWhan, A.F.

    1982-01-01

    Background signal in a PTFE based dosemeter caused by impurities in the PTFE and in the active component such as lithium fluoride is substantially reduced by treating the dosemeter with acid. The optimum treatment involves use of hydrofluoric acid at room temperature for approximately one minute, followed by thorough washing with methanol, and finally drying. This treatment is best applied after the original manufacture of the dosemeters. It may also be applied to existing dosemeters after they have been in use for some time. The treatment produces a permanent effect in reducing both the light induced signal and the non-light induced signal. The process may be applied to all types of dosemeter manufactured from PTFE or other plastics or resins which are able to resist brief exposure to acid. The treatment works particularly well with dosemeters based on PTFE and lithium fluoride. It is also applicable to dosemeters based on calcium sulphate, lithium borate and magnesium borate. Acids which may be used include hydrofluoric, hydrochloric, nitric, phosphoric and sulphuric. (author)

  6. Study about the feasibility of using an electret dosemeter as a personal dosemeter

    International Nuclear Information System (INIS)

    Leitao, I.P.

    1983-01-01

    A feasibility study of the electret dosemeters as a personnel dosemeter was carried out. Preliminary tests were applied, in order to assess the dosemeter response to radiation, linearity, stability, reproductibility, direcional dependence and energy dependence in energy range from 33 to 1250 KeV. In general the results are in agreement with the recommendations of the Commision of the European Communities (CEC) for the use of this device as a personnel dosemeter with the exception of the energy dependence and the stability at medium term. (Author) [pt

  7. A new electret dosemeter for radiotherapy

    International Nuclear Information System (INIS)

    Rodrigues, L.N.

    1985-01-01

    The results obtained with a new plane electret dosemeter for use in Radiotherapy are presented. The working principle of the electret dosemeter in based on the use of the electret field the ion collecting field, similarly to an ionization chamber, and as charge integrator detector. The dosemeter had, initialy, a cylindrical geometry. The results attained with it's calibration curve concerning the sensitivity, the stability and the reproducibility lead to changes in the dosemeter geometry. A plane geometry dosemeter was built in order to increase the useful exposure range. The plane dosemeter sensitivity dependence was measured versus the electret charging conditions, the chamber volume and wall material (aluminium, brass and stainless steel). The stainless steel dosemeter showed the best results. This dosemeter has the following characteristics: sensitivity 10 -13 C/R, volume 0.20 cm 3 . Compared to the Baldwin-Farmer dosemeter, this results are fairly good. A multiple electret dosemeter was developed to monitor the uniformity of the radiation beam for a Cobalt Teletherapy unit. The intercomparasion with the Baldwin-Farmer unit presented a maximum variation of 3%. (author) [pt

  8. Alarm personal dosemeter

    International Nuclear Information System (INIS)

    Nunomiya, Tomoya; Yamauchi, Hideshi; Shibata, Tetsuo

    2007-01-01

    Fuji Electric advanced the development of the conventional alarm personal dosemeter (APD) by adopting JIS Z 4312 (2002), which reflects IEC61526 (1998), and by improving the radiation performance characteristics, electromagnetic performance characteristics and mechanical performance characteristics of the APD (acquiring a CE marking). This new dosemeter will target overseas market in the future. The APD is a suitable dosemeter for detecting and monitoring radiation exposure to personnel working in the controlled areas of nuclear facilities, such as nuclear power stations. The APD product line includes 'gamma ray', 'gamma ray + beta ray' and 'gamma ray + neutron' models. (author)

  9. Performance tests on the NRPB thermoluminescent dosemeter

    CERN Document Server

    Shaw, K B

    1977-01-01

    Performance tests on the thermoluminescent dosemeter, designed at NRPB for use in the automated personal dosimetry system, are described. An ultra-thin lithium borate dosemeter has been developed for skin absorbed dose measurement. The X-ray, gamma-ray and beta-ray energy response of the dosemeter has been investigated and the angular response for the dosemeter has been examined. The annealing, read-out and stabilisation procedures for the dosemeter are described.

  10. Fast neutron sensitivity of polymer dosemeters

    International Nuclear Information System (INIS)

    Harper, M.W.; Pearson, D.W.; Moran, P.R.

    1975-01-01

    The responses of polymer thermocurrent dosemeters to fission spectrum and 14 MeV neutrons were measured. The dosemeters are in the form of disks 1 cm diam by 0.5 mm thick. Relative to Cobalt 60 gamma responses, teflon PTFE dosemeters show a 6 percent response to 14 MeV neutrons and a 5 percent response to fission neutrons on a tissue rad basis. Polymethylpentene dosemeters show a 49 percent response to 14 MeV neutrons and a 40 percent response to fission neutrons on a tissue rad basis when provided with adequate recoil proton buildup. The sensitivity of these dosemeters is limited to neutron doses greater than 10 rads by spurious background currents

  11. Quality control for dosemeters

    International Nuclear Information System (INIS)

    Di Prinzio, R.

    1988-01-01

    Several tests and intercomparison of the secondary standard dosemeter calibration in Rio de Janeiro are described. Periodical tests, such as leakage current and the comparison between the secondary standard dosemeter in Rio de Janeiro e Sao Paulo are shown. (E.G.) [pt

  12. Personal neutron diode dosemeter

    International Nuclear Information System (INIS)

    Barthe, J.; Lahaye, T.; Moiseev, T.; Portal, G.

    1993-01-01

    The control and management of neutron doses, received by workers in nuclear power or research facilities, requires a knowledge of cumulated dose equivalent or dose equivalent rate in real time. Individual dosemeters so far developed for this purpose are scarce and not very satisfactory. Passive dosemeters such as TLD systems based on the albedo effect, nuclear emulsions or solid track detectors, do not give sufficiently accurate measurements. Furthermore, the increase in the quality factor and the more restrictive new ICRP recommendations diminish the maximum admissible threshold making currently used systems obsolete. Other than bubble dosemeter systems, based on thermodynamic effects of a superheated gel, no simple electronic device is available at the present time. The development of diode based dosimetric gamma badges, having a size similar to that of credit cards, has stimulated us to design and develop a personal neutron dosemeter based on a double diode system. The results obtained are very encouraging and practical models should become available in the near future. (author)

  13. Self-indicating radiation alert dosemeter (SIRAD)

    International Nuclear Information System (INIS)

    Riel, G. K.; Winters, P.; Patel, G.; Patel, P.

    2006-01-01

    In an event of a nuclear or dirty bomb explosion and a radiological accident, there is a need for self-indicating instant radiation dosemeter for monitoring radiation exposure. The self-indicating instant radiation alert dosemeter (SIRAD) is a credit card size radiation dosemeter for monitoring ionising radiation from a few hundredths of a Gray to a few Gray. It is always active and is ready to use. It needs no battery. The dosemeter develops colour instantly upon exposure, and the colour intensifies with dose. It has a colour chart so that the dose on the active element may be read by matching its colour with the chart that is printed next to it on the card. However, in this work, the dose is measured by the optical density of the element. The dosemeter cannot be reset. The response changes by 3 y at room temperature. It contains no hazardous materials. The dosemeter would meet the requirements of instantly monitoring high dose in an event of a nuclear or dirty bomb explosion or a radiation accident. (authors)

  14. Self-indicating radiation alert dosemeter (SIRAD).

    Science.gov (United States)

    Riel, Gordon K; Winters, Patrick; Patel, Gordhan; Patel, Paresh

    2006-01-01

    In an event of a nuclear or dirty bomb explosion and a radiological accident, there is a need for self-indicating instant radiation dosemeter for monitoring radiation exposure. The self-indicating instant radiation alert dosemeter (SIRAD) is a credit card size radiation dosemeter for monitoring ionising radiation from a few hundredths of a Gray to a few Gray. It is always active and is ready to use. It needs no battery. The dosemeter develops colour instantly upon exposure, and the colour intensifies with dose. It has a colour chart so that the dose on the active element may be read by matching its colour with the chart that is printed next to it on the card. However, in this work, the dose is measured by the optical density of the element. The dosemeter cannot be reset. The response changes by 3 y at room temperature. It contains no hazardous materials. The dosemeter would meet the requirements of instantly monitoring high dose in an event of a nuclear or dirty bomb explosion or a radiation accident.

  15. Principle and use of dosemeters

    International Nuclear Information System (INIS)

    Genet, S.; Ribaud, I.

    1997-01-01

    The institute of nuclear physics of Orsay is accepted by the Ministry of Labour to insure the surveillance of workers individual external exposure against the danger of ionizing radiations and to execute monitoring of radiation protection. The dosemeters studied in this report are the photographic film dosemeters ( for x rays, gamma rays and beta - rays), the trace detectors (fast neutrons) and the radio thermo luminescent dosemeters. For each type, the principle and how to use it are given. (N.C.)

  16. Development trends of radiophotoluminescent glass dosemeter

    International Nuclear Information System (INIS)

    Ikegami, T.

    2004-01-01

    RPL glass dosemeter has been recently recognized to have a good performance as accumulation dosemeter and has been routinely used for personal dosimetry and environmental radiation monitoring. Furthermore, its applicable field is being extending to medical radiation measurement. The history of RPL glass dosemeter is very long. It was born in USA in 1950s and after that it was improved in Japan. And it was used as personal dosemeter in 1970s. But, in those days, RPL glass dosemeter was not suitable to low dose measurement due to some handling problems. So, its use had been reduced gradually. The author has broken through any past problems, by mainly realizing the pulsed UV excitation method. In this paper, the development history, principle and features, and the development good results of the pulsed UV excitation method are summarized, including the introduction of recent RPL glass dosimetry products. (author)

  17. Response of electret dosemeter to slow neutrons

    International Nuclear Information System (INIS)

    Ghilardi, A.J.P.; Pela, C.A.; Zimmerman, R.L.

    1987-01-01

    The response of electret dosemeter to slow neutrons exposure is cited, mentioning the preparation and the irradiation of dosemeter with Am-Be source. Some theory considerations about the response of electret dosemeter to slow and fast neutrons are also presented. (C.G.C.) [pt

  18. Optical readout method for solid-state dosemeters

    International Nuclear Information System (INIS)

    McDonald, J.C.; Eichner, F.N.; Stahl, K.A.; Miller, S.D.

    1986-07-01

    The readout of solid-state dosemeters is usually accomplished by heating to produce thermoluminescence. This technique has several disadvantages including stressing the dosemeter crystals, melting Teflon enclosures, and destroying the thin dosemeters designed for beta particle measurements. An optical readout method is being developed to avoid these difficulties. Standard dosemeters were irradiated to a dose of approximately 0.02 Sv with 137 Cs gamma rays. The dosemeters were then irradiated with light produced by a high-intensity xenon lamp. Various wavelength bands, from the ultraviolet through the visible and to the near-infrared, were used. The degree of trap emptying was found to be proportional to the total optical power incident. With the intensities used in the preliminary experiments, over 90% trap emptying was achieved. This new technique will prove useful for dosemeters that are encased in plastic for automatic processing. The details of this optical readout method, along with some possible applications in neutron and beta dosimetry are described. 7 refs., 3 figs

  19. EDEL: ENEA dosemeter for eye lens

    International Nuclear Information System (INIS)

    Ferrari, Paolo; Mariotti, Francesca; Campani, Lorenzo

    2016-01-01

    Since the publication of International Commission on Radiological Protection statement in 2011 on tissue reaction, eye lens radiation protection played an important role in exposed personnel dosimetry. For this reason, the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) Individual Monitoring Service decided to study a prototype to fulfil specific requests (e.g. for survey in interventional department and intercomparisons). On the basis of such preliminary investigation, a new eye lens dosemeter was developed. The new dosemeter, named EDEL (ENEA Dosemeter for Eye Lens), was characterised in terms of H p (3), the operational quantity related to eye lens monitoring. The investigation was performed experimentally and optimised using the Monte Carlo MCNP6 code. The new prototype was thought to fulfil two main requests: the reliability of the dosimetric data and the portability of the dosemeter itself. The new dosemeter will soon be supplied to the collaborating hospitals for workplace test measurements. (authors)

  20. Technical specification of the NRPB Nuclear Emulsion Dosemeter

    International Nuclear Information System (INIS)

    Bartlett, D.T.; Bird, T.V.

    1978-08-01

    This document is a formal specification of the NRPB Nuclear Emulsion Dosemeter. The dosemeter specified in this report replaces the NRPB Fast Neutron Personal Dosemeter specified in NRPB-R50. (author)

  1. Hsp 70 and 90 proteins as bio indicators of stress and protein damage in human lymphocytes exposed to neutrons

    International Nuclear Information System (INIS)

    Delgado, C. E.; Letechipia de L, C.; Vega C, H. R.; Sanchez R, S. H.

    2016-09-01

    Neutrons, when interacting with the cells of the body produce free radicals, so that exposure to high doses of ionizing radiation can cause different damage to the body that can cause cell death, therefore, these effects will depend on the amount of dose, time and individual factors such as gender, age, health status and nutrition. Therefore, knowledge of cellular responses to radiation exposure is critical for developing predictive markers useful for assessing people's exposure to radiation. The purpose of this study was to estimate the cellular protein damage through the Hsp 70 and 90 proteins exposed to neutrons in human lymphocytes from clinically healthy subjects. The cell tissue was obtained by venipuncture, the lymphocytes were separated by Ficoll-Paque concentration gradient, the experimental batches were formed, thus having 5 duplicate samples, subjected to neutron irradiation in a "2"4"2Am-Be at doses of 0.25, 0.50, 0.75, 1 and 1.25 μGy at three distances 20, 21.5 and 23 cm. As a positive control, a sample exposed to heat (40 degrees Celsius) was used for 40 min. The proteins of the experimental batch were analyzed by Western-Blot and protein quantification was analyzed by densitometry, on the other hand the oxidative stress was quantified by Oxi-Blot. Was found that the neutrons at doses of 0.25 and 0.5 μGy over expressed the Hsp-70 proteins, but for Hsp-90 no over-dose expressed, there was no protein damage at the exposure doses that were established. It can be estimated that Hsp-70 proteins can serve as bio indicators of cell stress by exposure doses of 0.25 and 0.5 μGy of neutrons. (Author)

  2. A new extremity dosemeter for beta and gamma radiation

    International Nuclear Information System (INIS)

    Heinzelmann, M.; Pagenkamper, M.

    1988-01-01

    An extremity dosemeter developed at the Juelich Nuclear Research Centre is very well suited for the precise and energy-independent measurement of the skin dose generated by beta or gamma radiation. This is also confirmed by the results of this intercomparison programme. The dosemeter contains three TLDs of LiF in Teflon mounted behind a window of 0.9 mg/cm 2 . The great advantage of this dosemeter is three TLD's enabling statements about the radiation quality. However, the dosemeter has two disadvantages The dosemeter is complicated to manufacture. A very thin plastic foil of 0.9 mg/cm 2 must be attached to a support. This work is difficult and time-consuming and cannot be automated. The window in front of the TLD is not sturdy enough and is occasionally destroyed when the dosemeter is being worn. These two disadvantages prevent this extremity dosemeter from being used more frequently. For this reason, work was begun on developing a new extremity dosemeter without these two disadvantages. The great advantage of the previous dosemeter of obtaining statements about the type of radiation with the aid of readings from three TLD's was to be retained. The improved extremity dosemeter has a more sturdy and thicker window with a similar response as the previous dosemeter with a thinner window

  3. Selected references on thermoluminescent dosemeters for personnel monitoring

    International Nuclear Information System (INIS)

    Lawson, Helen

    1976-08-01

    This bibliography contains references on: specific thermoluminescent dosemeters used for personnel dosimetry; comparisons of thermoluminescent and other dosemeters for personnel monitoring and read-out apparatus for thermoluminescent dosemeters. An appendix contains selected foreign language references. (author)

  4. Calibrations of pocket dosemeters using a comparison method

    International Nuclear Information System (INIS)

    Somarriba V, I.

    1996-01-01

    This monograph is dedicated mainly to the calibration of pocket dosemeters. Various types of radiation sources used in hospitals and different radiation detectors with emphasis on ionization chambers are briefly presented. Calibration methods based on the use of a reference dosemeter were developed to calibrate all pocket dosemeters existing at the Radiation Physics and Metrology Laboratory. Some of these dosemeters were used in personnel dosimetry at hospitals. Moreover, a study was realized about factors that affect the measurements with pocket dosemeters in the long term, such as discharges due to cosmic radiation. A DBASE IV program was developed to store the information included in the hospital's registry

  5. Electret dosemeter for beta radiation

    International Nuclear Information System (INIS)

    Campos, L.L.; Caldas, L.V.E.; Mascarenhas, S.

    The response characteristics of an electret dosemeter for beta radiation are studied. Experiments were performed using different geometries and walls, and it was verified for which geometry the dosemeter sensitivity is greater. Sources of 90 Sr - 90 Y, 204 Tl and 85 Kr were used in the experiments. (I.C.R.) [pt

  6. Comparing different error-conditions in film dosemeter evaluation

    International Nuclear Information System (INIS)

    Roed, H.; Figel, M.

    2007-01-01

    In the evaluation of a film used as a personal dosemeter it may be necessary to mark the dosemeters when possible error-conditions are recognised, such as errors that have an influence on the ability to make a correct evaluation of the dose value. In this project a comparison has been carried out to examine how two individual monitoring services, IMS [National Inst. of Radiation Hygiene (Denmark) (NIRH) and National Research Centre for Environment and Health (Germany) (GSF)], from two different EU countries mark their dosemeters. The IMS are different in size, type of customers and issuing period, but both use films as their primary dosemeters. The error-conditions examined are dosemeters exposed to moisture or light, contaminated dosemeters, films exposed outside the badge, missing filters in the badge, films inserted incorrectly in the badge and dosemeters not returned or returned too late to the IMS. The data are collected for the year 2003 where NIRH evaluated ∼50,000 and GSF ∼1.4 million film dosemeters. The percentage of film dosemeters is calculated for each error-condition as well as the distribution among eight different employee categories, i.e. medicine, nuclear medicine, nuclear industry, industry, radiography, laboratories, veterinary and others. It turned out, that incorrect insertion of the film in the badge was the most common error-condition observed at both IMS and that veterinarians, as the employee category, generally have the highest number of errors. NIRH has a significantly higher relative number of dosemeters in most error-conditions than GSF, which perhaps reflects that a comparison is difficult due to different systemic and methodical differences between the IMS and countries, e.g. regulations and monitoring programs etc. Also the non-existence of a common categorisation method for employee categories contributes to make a comparison like this difficult. (authors)

  7. Passive neutron dosemeter with activation detector

    Energy Technology Data Exchange (ETDEWEB)

    Valero L, C.; Banuelos F, A.; Guzman G, K. A.; Borja H, C. G.; Hernandez D, V. M.; Vega C, H. R., E-mail: fermineutron@yahoo.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2011-10-15

    A passive neutron dosemeter with {sup 197}Au activation detector has been developed. The area dosemeter was made as a 20.5 {phi} x 20.5 cm{sup 2} polyethylene moderator, with a polyethylene pug where a {sup 197}Au foil can be located either parallel or perpendicular to moderator axis. Using Monte Carlo methods, with the MCNP5 code. With the fluence response and the fluence-to-equivalent dose conversion coefficients from ICRP-74, responses to H*(10) were also calculated, these were compared against responses of commercially available neutron area monitors and dosemeters. (Author)

  8. The need for comparison of diagnostic dosemeters

    International Nuclear Information System (INIS)

    Kramer, H.M.

    1989-01-01

    One precondition for successfully implementing quality control in diagnostic radiology is that the measuring instruments used are of adequate quality. Among the measuring instruments used for quality control, dosemeters play a predominant role. Therefore it is essential to know the performance characteristics of a suitable dosemeter and to have information on the uncertainties and measurement errors found during acceptance testing. An outline will be given of the requirements on the accuracy of dosemeters. Such requirements have to address the task of the dosemeter and also take into account their technical feasibility. In order to gather information on the performance characteristics of field instruments, a programme for a European intercomparison has been developed which was carried out in 1988. The programme, together with its underlying ideas and its objectives, is presented in this paper. (author)

  9. New ISO standard - personnel photographic film dosemeters

    International Nuclear Information System (INIS)

    Brabec, D.

    1980-01-01

    The ISO Standard 1757 ''Personnel Photographic Film Dosemeters'', issued in June 1980, is briefly described. UVVVR's own dosemeter developed for use in the national film dosimetry service in Czechoslovakia is evaluated in relation to this ISO Standard. (author)

  10. Application of radiophotoluminescence dosemeters for environmental monitoring

    International Nuclear Information System (INIS)

    Mihara, A.; Tamura, T.; Mochizuki, T.; Numakunai, T.; Yoshida, Y.; Ohi, Y.

    1993-01-01

    Feasibility study has been made on the radiofluorescence glass (RPL) dosemeters for environmental radiation monitoring. Main items in the laboratory tests are batch uniformities of pre-dose and sensitivity, build-up characteristics of RPL intensity, energy and angular responses, stabilities for RPL reading, anneal cycling and climatic conditional changes. We have determined self-irradiation dose and cosmic ray contribution. Radiation monitoring field test for the RPL dosemeters has been conducted in comparison with the present TLD systems. A procedure manual for the environmental monitoring by the use of RPL dosemeters is in preparation

  11. Response of electret dosemeter to slow neutrons

    International Nuclear Information System (INIS)

    Ghilardi, A.J.P.; Pela, C.A.; Zimmerman, R.L.

    1987-01-01

    The response of the electret dosemeter to exposition of slow neutrons is studied. Different external coatings are used on the dosemeter (polyethylene, alminium, polyethylene + boron, aluminium + boron) and exposure curves (with and without water) are compared. (M.A.C.) [pt

  12. Needle-type differential thermoluminescent dosemeter

    International Nuclear Information System (INIS)

    Kubu, M.

    1988-01-01

    The dosemeter serves to measure the depth distribution of absorbed dose in a phantom in mixed neutron and gamma radiation fields. It consists of a stratified cylindrical absorber in which alternate moderator and cadmium layers. Inside are two bores along the longitudinal axis for tubes filled with 6 LiF and 7 LiF powder thermoluminescent dosemeters. The device is easily portable and allows to carry out measurements with a high level of reproducibility. (J.B.). 4 figs

  13. Colour dosemeters for high level radiation dosimetry

    DEFF Research Database (Denmark)

    Schönbacher, H.; Coninckx, F.; Miller, A.

    1990-01-01

    interpretation or a dose measurement with a simple instrument such as a portable reflecting densitometer in the range of 10(3) to 10(6) Gy. Two projects were investigated: (1) a thin plastic film with a self adhesive tape containing a radiochromic dye which induces a colour change when exposed to ionising...... of paint and film dosemeters were installed in the 450 GeV Super Proton Synchrotron (SPS) at CERN and irradiated during operation for more than two years. Within the useful range of the dosemeters, dose comparisons with other dosemeter types gave satisfactory results. Application in other fields...

  14. Evaluation of BICRON NE MCP DXT-RAD passive extremity dosemeter

    CERN Document Server

    Yuen, P S; Frketich, G; Rotunda, J

    1999-01-01

    Passive extremity dosemeters currently used in dosimetry communities worldwide have shortcomings. In general, an extremity dosemeter has too thick a detector element, and the dosemeter response is highly energy dependent for beta rays with energies ranging from 200 keV to 2 MeV. It often does not have dosemeter identification, causing problems in the chain of custody. It is often read manually, rendering reading/packing operations very labour intensive. As a result of collaboration between AECL and BICRON NE, a new extremity dosemeter, incorporating a highly sensitive LiF:Mg,Cu,P TLD and tentatively code named MCP DXT-RAD, was developed. It has been evaluated for radiological performance against an ISO draft standard for extremity dosemeters in twelve categories: homogeneity, detection threshold, beta ray energy response, beta angular response, photon energy response, photon angular response, reproducibility, stability under various climatic conditions, linearity, residue, self irradiation, and effect of ligh...

  15. Factors affecting polyamide prototypes design of Albedo dosemeters

    International Nuclear Information System (INIS)

    Martins, M.M.; Mauricio, C.L.P.; Fonseca, E.S.

    1996-01-01

    This work studies the most important factors which affect the response of albedo neutron dosemeters containing LiF TLDs with the aim to improve their sensitivity. It includes tests of thickness and shape of the polyamide moderator body prototypes, albedo window diameter and TLD position inside the moderator. Analyzing the results, an albedo neutron dosemeter prototype, B 4 C covered, was developed. The prototype has a response three times higher than the albedo dosemeter now in use in Brazil. (author)

  16. Dosimertry characteristics and performance comparisons: Environmental radiophotoluminescent glass dosemeters versus thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Lee, J.H.; Lin, M.S.; Hsu, S.M.; Chen, I.J.; Chen, W.L.; Wang, C.F.

    2009-01-01

    This paper describes the dosimetry characteristic comparison of environmental radiophotoluminescent glass dosemeter (RPLGD) and thermoluminescent dosemeter (TLD) systems employed at the Institute of Nuclear Energy Research (INER, Taiwan). The luminescence centers of TLD disappeared by reading process, and repetition of measurement is impossible. RPLGDs can be repeatedly read and keep the luminescence centers for a long time. The RPLGD fading is about 1% within 30 days after being exposed to ionizing radiation. Environmental cumulative doses measured by a RPLGD and a TLD were compared at the same monitoring points of INER during two years. The sensitivity of TLD decreased with gradual loss due to fading at higher temperatures. The difference between results obtained by RPLGD and TLD is discussed mainly with respect to the dependence on the ambient temperature. In addition, this research also refers to the American National Standard Institute (ANSI) Draft Standard N13.29 (1996) to organize the environmental dosimetry performance tests of the INER's RPLGDs and the TLDs. The results mean that both kinds of dosemeters can meet the performance test criteria. An accreditation procedure for the institutes which provide the environmental dosimetry services in Taiwan was suggested based on the comparison results of these two dosimetry systems

  17. The NRPB automated thermoluminescent dosemeter and dose record keeping system

    International Nuclear Information System (INIS)

    Dennis, J.A.; Marshall, T.O.; Shaw, K.B.

    1975-03-01

    This report describes the thermoluminescent personal radiation dosemeter and its associated automated processing equipment, which are being developed by the National Radiological Protection Board, together with the operation of a computerised dosemeter issue and record keeping system. The main justifications for introducing these systems are improvements in the organizational efficiency of the maintenance of individual dose records, a more flexible and accurate dosimetry system, and economics in operational costs. The dosemeter is based on a numbered aluminium plate containing two lithium fluoride in polytetrafluorethylene disks for the measurement of surface and body dose. This dosemeter is wrapped in thin plastic and labelled with the wearer's name and address. On return, the dosemeter is checked automatically for radioactive contamination; it is unwrapped and evaluated; the dose readings are included in the wearer's stored dose record; the dosemeter is annealed and is then available for re-issue to another wearer. Dose reports and warnings are automatically issued to the wearer or his employer. (author)

  18. Results of the EURATOM programme for comparison of individual dosemeters

    International Nuclear Information System (INIS)

    Julius, H.W.

    1976-01-01

    The results of the EURATOM dosemeter comparison-program for dosemeters used in the member states are given. Especially the results obtained in the Netherlands are examined and evaluated. The design and characteristics of the badge developed by the TNO-RD which are based on a thermoluminescent dosemeter are given

  19. EURADOS intercomparisons on whole body and extremity dosemeters (2008–2009) – Results and comparison of different dosemeter designs

    International Nuclear Information System (INIS)

    Stadtmann, H.; Grimbergen, T.W.M.; Figel, M.; Romero, A.M.; Mcwhan, A.F.

    2011-01-01

    The EURADOS (European Radiation Dosimetry Group) working group (WG2) on Harmonisation of Individual Monitoring in Europe has shown that intercomparisons are fundamental for harmonisation of individual monitoring. As a result of these considerations, EURADOS started to prepare a series of continuous intercomparisons for individual monitoring services (IMS) in Europe. EURADOS has now successfully executed two intercomparison exercises, one for whole body dosemeters (2008) and one for extremity dosemeters (2009). Both exercises were performed without external funding, all costs being covered by the participants’ fees. More than 120 (!) different – mainly passive – dosimetry systems were tested from all over Europe until now and the results were analysed and compared. Although scientific studies were not the primary objective of these exercises specific additional information about the tested systems supplied by the participants for statistical analysis allows a detailed analysis of these results with respect to different parameters like dosemeter type, detector material, filter thickness or others design parameters. The influence of such parameters on the response values of the dosemeters is analysed and discussed in this paper. Both energy response as well as directional response for beta and photon radiation are considered. The influence of different design parameters e.g. detector material, is analysed by comparing the frequency distribution of the response values for different dosemeter groups. Pronounced differences for different detector materials (LiF:Mg,Ti, LiF:Mg,Cu,P and Li 2 B 4 O 7 /CaSO 4 ) were found. The paper gives a comprehensive overview on the performance of various European dosimetry services and the influence of the dosemeter design on the resulting response values.

  20. The new IRSN passive dosemeter using the RPL technique

    International Nuclear Information System (INIS)

    Fraboulet, P.; Cale, E.; Itie, C.; Bottollier-Depois, Jean-Francois

    2008-01-01

    Full text: The Institute for Radiological Protection and Nuclear Safety (IRSN) is the French public organisation in charge of research and expertise into nuclear safety and radiation protection. IRSN provides also services in these areas like dosimetric survey for 150,000 workers liable to be exposed to ionising radiation. At present whole-body dosemeters provided by the IRSN laboratory for photons and beta-particles are based on photographic films. In order to anticipate likely supplying decrease and to improve the service, IRSN has decided to replace photographic films by dosemeters based on the radio-photoluminescence (RPL) technology, supplied by the Japanese Company Chiyoda Technol. RPL was chosen after a thorough comparison with other available passive techniques (thermoluminescent dosemeters: TLD, and optically stimulated luminescence: OSL). Constraints due to large-scale production of dosemeters (packaging, shipping, etc.) were taken into account as well. Irradiation tests for five different dosemeters, based on the 3 available techniques (TLD, OSL, RPL) were performed. The main results of these tests are presented (energy, dose and angular response, detection threshold, etc.) together with main technical characteristics of the new RPL dosemeter (range in energy and dose, homogeneity, reproducibility, re-reading, information about radiation type from reading, etc.). This dosemeter is expected to give significative improvements in the IRSN laboratory's provision of service thanks to better dosimetric performances and because it offers the possibility to get information to analyse over-exposure circumstances. (author)

  1. Glass as a gamma ray dosemeter

    International Nuclear Information System (INIS)

    Sutrisno Puspodikoro.

    1978-01-01

    The advantages of glass as a γ-rays dosemeter are studied. Experiments have shown that ordinary microscope object glass can be used as a dosemeter, which dose range for linear response extends from about 10 4 -10 6 rads. Heat treatment of the irradiated samples accelerates the initial fading of coloration and stabilizes the residual optical density. On the other side cooling of them retards the initial fading. (author)

  2. Hsp 70 and 90 proteins as bio indicators of stress and protein damage in human lymphocytes exposed to neutrons; Proteinas Hsp 70 y 90 como bioindicadores de estres y dano proteico en linfocitos humanos expuestos a neutrones

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, C. E.; Letechipia de L, C.; Vega C, H. R.; Sanchez R, S. H., E-mail: rmfranccesco00223@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2016-09-15

    Neutrons, when interacting with the cells of the body produce free radicals, so that exposure to high doses of ionizing radiation can cause different damage to the body that can cause cell death, therefore, these effects will depend on the amount of dose, time and individual factors such as gender, age, health status and nutrition. Therefore, knowledge of cellular responses to radiation exposure is critical for developing predictive markers useful for assessing people's exposure to radiation. The purpose of this study was to estimate the cellular protein damage through the Hsp 70 and 90 proteins exposed to neutrons in human lymphocytes from clinically healthy subjects. The cell tissue was obtained by venipuncture, the lymphocytes were separated by Ficoll-Paque concentration gradient, the experimental batches were formed, thus having 5 duplicate samples, subjected to neutron irradiation in a {sup 242}Am-Be at doses of 0.25, 0.50, 0.75, 1 and 1.25 μGy at three distances 20, 21.5 and 23 cm. As a positive control, a sample exposed to heat (40 degrees Celsius) was used for 40 min. The proteins of the experimental batch were analyzed by Western-Blot and protein quantification was analyzed by densitometry, on the other hand the oxidative stress was quantified by Oxi-Blot. Was found that the neutrons at doses of 0.25 and 0.5 μGy over expressed the Hsp-70 proteins, but for Hsp-90 no over-dose expressed, there was no protein damage at the exposure doses that were established. It can be estimated that Hsp-70 proteins can serve as bio indicators of cell stress by exposure doses of 0.25 and 0.5 μGy of neutrons. (Author)

  3. Dosimetric characteristics of a TLD dosemeter with extremities

    International Nuclear Information System (INIS)

    Molina P, D.; Diaz B, E.; Lien V, R.

    1999-01-01

    It was designed a TLD dosemeter for the monitoring of the extremities. This one consists in a metallic ring with a circular orifice where is arranged a T L detector of LiF: Mg,Ti (Model JR1152C) 5 x 5 x 0.8 mm 3 covered by a polyethylene fine layer. In this work were studied the dosimetric properties of the dosemeter for its application in the dosimetry of extremities for photonic radiation. the results obtained allow conclude that the designed dosemeter can be used for the extremities monitoring. (Author)

  4. A personal radon dosemeter

    International Nuclear Information System (INIS)

    Oberstedt, S.; Vanmarcke, H.

    1994-03-01

    In the last decade the radon issue has become one of the major problems of radiation protection. Animal studies as well as epidemiological studies showed an increased lung cancer risk. A new personal radon-dosemeter on the basis of a CR-39 (poly-allyl diglycol carbonate) track-etch detector has been developed. The read-out of the detectors is based on the image- processing technique. The actual efficiency of the new dosemeter, obtained with a semi-automatic personal-computer based image-analysis system, is 1.43 +/- 0.15 tracks/cm 2 /(kBq/m 3 h), which is about three times that of the widely used Karlsruhe-type detector based on polycarbonate detectors

  5. Using operational equipment to read accident dosemeters.

    Science.gov (United States)

    Devine, R T; Vigil, M M; Martinez, W A

    2004-01-01

    Analysis of accident dosemeters usually involves the use of laboratory-based counting equipment. Gamma spectrometers are used for indium, copper and gold, and alpha-beta detectors for sulphur. This equipment is usually not easily transported due to the shielding required and the weight and delicacy of the counters. For intercomparison studies that require reading the dosemeters on site, a transportable system is required unless the site operating the study can count samples for all the participants. In the case of an actual accident these systems would have a difficulty in counting a large number of accident dosemeters. In an accident, personnel are usually subdivided according to their level of exposure. Those exposed to higher doses are treated immediately. An alternate system should be made available to handle the dosemeters worn by those personnel are likely to receive lower doses. Improvements in portable operational equipment for gamma and beta monitoring allow their use as spectrometers. Such a system was used for the SILENE intercomparison conducted at IRSN Valduc on 12 June and 19, 2002, and the preliminary results compared well with the other participants.

  6. Calibration of clinical dosemeters in the IAEA water phantom

    International Nuclear Information System (INIS)

    Caldas, L.V.E.; Albuquerque, M.P.P.

    1994-01-01

    The procedures recommended by the IAEA Code of Practice were applied at the Calibration Laboratory of Sao Paulo in order to provide in the future the clinical dosemeters users with absorbed dose to water calibration factors for Cobalt 60 radiation beams. In this work the clinical dosemeters were calibrated free in air and in water, and the results were compared, using conversion factors. The several tested clinical dosemeters of different manufacturers and models belong to the laboratory and to hospitals. For the measurements in water the IAEA cubic water phantom was used. The dosemeters were all calibrated free in air in terms of air kerma, and the calibration factors in terms of absorbed dose to water were obtained through conversion factors. the same dosemeters were also calibrated into the water phantom. Good agreement was found between the two methods, the differences were always less than 0.5%. The data obtained during this work show that when the dosemeters are used only in Cobalt 60 radiation and the users apply in the hospital routine work the IAEA Code of Practice, the calibration can be performed directly in the water phantom. This procedure provides the useful calibration factors in terms of absorbed dose to water

  7. Electron scattering effects on absorbed dose measurements with LiF-dosemeters

    International Nuclear Information System (INIS)

    Bertilsson, G.

    1975-10-01

    The investigation deals with absorbed dose measurements with solid wall-less dosemeters. Electron scattering complicates both measurement of absorbed dose and its theoretical interpretation. The introduction of the dosemeter in a medium causes perturbations of the radiation field. This perturbation and its effect on the distribution of the absorbed dose inside the dosemeter is studied. Plane-parallel LiF-teflon dosemeters (0.005 - 0.1 g.cm -2 ) are irradiated by a photon beam ( 137 Cs) in different media. The investigation shows that corrections must be made for perturbations caused by electron scattering phenomena. Correction factors are given for use in accurate absorbed dose determinations with thermoluminescent dosemeters. (Auth.)

  8. Elaboration And Study Of Transfer Alanine/ESR Dosemeters

    International Nuclear Information System (INIS)

    Torres G, Luz A.

    1996-01-01

    The dosimetry is the dose measure imparted by the energy from the ionizing radiation to the matter. The dosemeters is the means used for the determination of such a dose. Diverse dosimetric classes exist, this classification depends in essence of the energy involved in the irradiation process and of its application necessity. It is as well as in radiological protection movie dosemeter is used, and TLD, in the calibration of units, as those of cobalt, the ionization cameras are used, in the detection of superficial contamination the accountants Geiger Muller and proportional etc. The transfer dosimeter Alanine/ESR is used, object of the present work, is characterized because after reading the registered dose, the information is conserved and it can be transferred and read in any team of ESR. Likewise the following dose that is imparted will be added to the previous one registered, this indicates that the dosemeters is of integral character. In the spectra taken ESR, it is determined that the integral double or area under the curve of the spectrum ESR is proportional to the concentration of free radicals generated by the radiation ionization and in turn this concentration is proportional to the dose received by the pills; in last, these proportionality relationships take to that the area under the curve of the spectrum main ESR is proportional to the radiation dose received by the alanine dosemeters. This dosemeter seeks to be an economic alternative that it will lend the calibration service that today offers the ionization Cameras or the acrylic red industrial dosemeters

  9. Australian participation in international intercomparisons of environmental dosemeters

    International Nuclear Information System (INIS)

    Boas, J.F.; David, R.C.; Jones, J.

    2002-01-01

    The Environmental Measurements Laboratory of the U.S. Department of Energy has conducted international intercomparisons of environmental dosemeters at regular intervals since 1974. This paper reports the results obtained in the 10th and 11th intercomparisons by JFB and JGY at the Australian Radiation Laboratory (in 1992 and 1996 respectively) and in the 12th intercomparison by JFB and DRCT at the Australian Radiation Protection and Nuclear Safety Agency and by JGY and JJ at Australian Radiation Serviceces during 2000 and 2001. The ARL/ARPANSA measurements used a simple dosemeter holder containing two CaSO 4 :Dy impregnated Teflon discs, one unshielded and the other shielded by approximately 2.4 mm of Cu. The ARS measurements used a commercially available TLD badge case containing a CaSO 4 :Dy impregnated Teflon card. The commercial badge case was not symmetrical in design. The filtration in the front and rear sections of the commercial badge case varied from an open area to an area shielded by copper, tin and cadmium. The results obtained were generally within ±15% of the reference values measured by EML using high-pressure ionisation chambers for dosemeters exposed hi the field to environmental radiation and for dosemeters given a single exposure to 137 Cs or 241 Am at EML or an associated laboratory. Similar agreement was obtained for dosemeters exposed in the field and also given a single exposure to 137 Cs radiation. In order to obtain this measure of agreement, the dosemeters were individually calibrated and the readouts corrected for fading. Copyright (2002) Australasian Radiation Protection Society Inc

  10. A new, passive dosemeter for gamma, beta and neutron radiations

    Energy Technology Data Exchange (ETDEWEB)

    Jones, L A; Stokes, R P, E-mail: rpstokes@dstl.gov.uk [Defence Science and Technology Laboratory, Environmental Sciences Department, Alverstoke, Gosport, Hants, PO12 2DL (United Kingdom)

    2011-03-01

    The Defence Science and Technology Laboratory (Dstl) provides personal radiation dosimetry to the UK Ministry of Defence. Dstl has recently developed a dosemeter that is based on a combination of thermoluminescent and etched-track detectors. The Dstl Combined Dosemeter is capable of assessing doses due to photons, beta particles and neutrons. This paper presents the laboratory type testing results for the Combined Dosemeter, and also describes the procedure for calibrating the dosemeter for use in workplace neutron fields. The Combined Dosemeter meets the type test requirements that are relevant to its intended applications, and gives neutron doses that are within 50% of the true dose in the workplaces in which it is used, even when the wearer has the potential to be exposed to a variety of neutron spectra (e.g. on board nuclear-powered submarines).

  11. A new, passive dosemeter for gamma, beta and neutron radiations

    International Nuclear Information System (INIS)

    Jones, L A; Stokes, R P

    2011-01-01

    The Defence Science and Technology Laboratory (Dstl) provides personal radiation dosimetry to the UK Ministry of Defence. Dstl has recently developed a dosemeter that is based on a combination of thermoluminescent and etched-track detectors. The Dstl Combined Dosemeter is capable of assessing doses due to photons, beta particles and neutrons. This paper presents the laboratory type testing results for the Combined Dosemeter, and also describes the procedure for calibrating the dosemeter for use in workplace neutron fields. The Combined Dosemeter meets the type test requirements that are relevant to its intended applications, and gives neutron doses that are within 50% of the true dose in the workplaces in which it is used, even when the wearer has the potential to be exposed to a variety of neutron spectra (e.g. on board nuclear-powered submarines).

  12. Improvement of the calibration technique of clinical dosemeters

    International Nuclear Information System (INIS)

    Ehlin Caldas, L.V.

    1988-08-01

    Clinical dosemeters constituted of ionization chambers connected to electrometers are usually calibrated as whole systems in appropriate radiation fields against secondary standard dosemeters in calibration laboratories. This work reports on a technique of component calibration procedures separately for chambers and electrometers applied in the calibration laboratory of IPEN-CNEN, Brazil. For electrometer calibration, redundancy was established by using a standard capacitor of 1000pF (General Radio, USA) and a standard current source based on air ionization with Sr 90 (PTW, Germany). The results from both methods applied to several electrometers of clinical dosemeters agreed within 0.4%. The calibration factors for the respective chambers were determined by intercomparing their response to the response of a certified calibrated chamber in a Co 60 calibration beam using a Keithley electrometer type 617. Overall calibration factors compared with the product of the respective component calibration factors for the tested dosemeters showed an agreement better than 0.7%. This deviation has to be considered with regard to an uncertainty of 2.5% in routine calibration of clinical dosemeters. Calibration by components permits to calibrate ionization chambers one at a time for those hospitals who have several ionization chambers but only one electrometer (small hospitals, hospitals in developing countries). 6 refs, 2 figs, 2 tabs

  13. Specification for personal photographic dosemeters

    International Nuclear Information System (INIS)

    1981-01-01

    The 1981 British/International Standard Specification, prepared under the direction of the Nuclear Engineering Standards Committee and TC85 of the International Organization for Standardization, is described for personal photographic dosemeters. The Standard specifies classification, characteristics and test procedures to determine absorbed doses due to X or gamma radiations (energy less than 3 MeV) and absorbed doses due to beta radiation (max. energy 0.6 to 3 MeV), whether or not accompanied by X, gamma or bremsstrahlung photon radiation. The Standard is particularly applicable to dosemeters intended to be carried on the chest or wrist. (U.K.)

  14. Calibration of Far West Technology (FWT-60) radiachromic dye dosemeters

    International Nuclear Information System (INIS)

    Mincher, B.J.; Zaidi, M.K.

    1992-01-01

    Radiachromic dye dosimetry was used to measure kilogray doses absorbed by various liquid samples during gamma-ray exposure in a spent nuclear fuel pool. The source of nuclear fuel was the Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory (INEL). Calibrations were performed using a 60 Co source and were run on bare dosemeters, as well as on dosemeters which mocked to simulate the samples. These dosemeters were prepared as a dye-impregnated nylon film and are commercially available. When exposed to gamma-ray doses of 0.5 to 200 kGy, a color change occurs which has an optical density proportional to absorbed dose. The difference in the calibration curves demonstrated the importance of irradiation of dosemeters under conditions as close to the actual samples as possible. Since these dosemeters could not be immersed directly in the organic solutions of interest, they were sandwiched between layers of lucite and stainless steel. This simulated the conditions inside an irradiated sample and provides a practical method of measuring absorbed doses. The reproducibility of measurements using the radiachromic dye dosemeters is also shown. 10 refs

  15. Environmental radiation measurements using lithium fluoride thermoluminescence dosemeters

    Energy Technology Data Exchange (ETDEWEB)

    Driscoll, C.M.H.; Green, B.M.R.; McKinlay, A.F.; Richards, D.J. (National Radiological Protection Board, Harwell (UK))

    1984-01-01

    The National Radiological Protection Board is involved in a large scale environmental survey of radiation levels in homes throughout the United Kingdom. Passive radon and gamma ray dosemeters are posted to a representative sample of households. Lithium fluoride thermoluminescence dosemeters are used to assess natural gamma radiation and are left in the measurement location for a period of six months before being returned to the Board for processing. As a preliminary to the national survey, the Board has been engaged on several limited surveys in regions of igneous and sedimentary geology. Experience gained in these limited surveys and from standardisation studies using environmental dosemeters are reported.

  16. Summary of personal neutron dosemeter results obtained within the EVIDOS project

    International Nuclear Information System (INIS)

    Luszik-Bhadra, M.; Reginatto, M.; Schuhmacher, H.; Bolognese-Milsztajn, T.; Lacoste, V.; Boschung, M.; Fiechtner, A.; Coeck, M.; Vanhavere, F.; Curzio, G.; Errico d', F.; Kylloenen, J.-E.; Lindborg, L.; Bartlett, D.; Tanner, R.

    2005-01-01

    Full text: Within the EC project EVIDOS ('Evaluation of Individual Dosimetry in Mixed Neutron and Photon Radiation Fields'), different types of neutron personal dosemeters were irradiated in workplace fields in nuclear installations in Europe. Mostly electronic personal neutron dosemeters were tested, among them commercial devices (Thermo Electron EPD-N, Aloka PDM-313), devices from first industrial prototype series (Thermo Electron EPD-N2, Saphydose-n) and laboratory prototypes which were already in the stage of lightweight battery-operated instruments (PTB DOS-2002). In addition, dosemeters with (almost) immediate readout (BTI bubble detectors, Rados DIS-N) and passive dosemeters which needed no fielddependent calibration factors (PADC track detectors from PSI and NRPB) were used, as well as those TLD albedo dosemeters which are routinely used in the facilities visited. The results of measurements obtained within the EVIDOS project in workplace fields in nuclear installations in Europe, i.e. at Kruemmel (boiling water reactor, transport cask), at Mol (Venus research reactor, fuel facility Belgonucleaire) and at Ringhals (pressurized water reactor, transport cask) are presented and compared to reference values of personal dose equivalent H p (10) determined by means of Bonner spheres and novel directional spectrometers. In fields with strong back-scatter and moderation of neutrons, several dosemeters showed overreadings by more than a factor of two. In strongly directed fields with neutron dose equivalent peaked at about 1 MeV (MOX fuel), the same dosemeters showed under-readings of about a factor of two. These under- and over-readings in the workplace fields can be explained in terms of the dosemeter response functions for mono-energetic neutrons, which show over-responses in the thermal and intermediate neutron energy region and under-responses at about 1 MeV neutron energy. The dosemeter readings obtained in the workplace fields were checked for consistency by

  17. The evaluation of multi-element personal dosemeters using the linear programming method

    International Nuclear Information System (INIS)

    Kragh, P.; Ambrosi, P.; Boehm, J.; Hilgers, G.

    1996-01-01

    Multi-element dosemeters are frequently used in individual monitoring. Each element can be regarded as an individual dosemeter with its own individual dose measurement value. In general, the individual dose values of one dosemeter vary according to the exposure conditions, i. e. the energy and angle of incidence of the radiation. The (final) dose measurement value of the personal dosemeter is calculated from the individual dose values by means of an evaluation algorithm. The best possible dose value, i.e. that of the smallest systematic (type B) uncertainty if the exposure conditions are changed in the dosemeter's rated range of use, is obtained by the method of linear programming. (author)

  18. Hsp40s specify functions of Hsp104 and Hsp90 protein chaperone machines.

    Directory of Open Access Journals (Sweden)

    Michael Reidy

    2014-10-01

    Full Text Available Hsp100 family chaperones of microorganisms and plants cooperate with the Hsp70/Hsp40/NEF system to resolubilize and reactivate stress-denatured proteins. In yeast this machinery also promotes propagation of prions by fragmenting prion polymers. We previously showed the bacterial Hsp100 machinery cooperates with the yeast Hsp40 Ydj1 to support yeast thermotolerance and with the yeast Hsp40 Sis1 to propagate [PSI+] prions. Here we find these Hsp40s similarly directed specific activities of the yeast Hsp104-based machinery. By assessing the ability of Ydj1-Sis1 hybrid proteins to complement Ydj1 and Sis1 functions we show their C-terminal substrate-binding domains determined distinctions in these and other cellular functions of Ydj1 and Sis1. We find propagation of [URE3] prions was acutely sensitive to alterations in Sis1 activity, while that of [PIN+] prions was less sensitive than [URE3], but more sensitive than [PSI+]. These findings support the ideas that overexpressing Ydj1 cures [URE3] by competing with Sis1 for interaction with the Hsp104-based disaggregation machine, and that different prions rely differently on activity of this machinery, which can explain the various ways they respond to alterations in chaperone function.

  19. Determination of isodose curves in Radiotherapy using an Alanine/ESR dosemeter

    International Nuclear Information System (INIS)

    Chen, F.; Baffa, O.; Graeff, C.F.O.

    1998-01-01

    It was studied the possible use of an Alanine/ESR dosemeter in the isodose curves mapping in normal treatments of Radiotherapy. It was manufactured a lot of 150 dosemeters with base in a mixture of D-L Alanine dust (80 %) and paraffin (20 %). Each dosemeter has 4.7 mm diameter and 12 mm length. A group of 100 dosemeters of the lot were arranged inside 50 holes of the slice 25 of the phantom Rando Man. The phantom irradiation was realized in two opposed projections (AP and PA) in Co-60 equipment. A group of 15 dosemeters was take of the same lot for obtaining the calibration curve in a 1-20 Gy range. After irradiation the signal of each dosemeter was measured in an ESR spectrometer operating in the X-band (∼ 9.5 GHz) and the wideness of Alanine ESR spectra central line was correlated with the radiation dose. The wideness dose calibration curve resulted linear with a correlation coefficient 0.9996. The isodose curves obtained show a profile enough similar at comparing with the theoretical curves. (Author)

  20. Individual monitoring with official electronic dosemeters in Germany - concepts and reality

    International Nuclear Information System (INIS)

    Martini, E.; Wahl, W.; Huebner, S.; Freynhagen, D.; Staemmler, M.

    2005-01-01

    Full text: Active (electronic) personal dosemeters (APD) are radiometers, which are equipped as active or passive dosimeters. They can directly indicate a dose rate and/or the dose integrated during a certain period (direct-indicating, active electronic personal dosemeters mentioned) or only over a separate reader (direct-selectable, passive electronic personal dosemeters mentioned). A concept is presented for the use of passive or active electronic personal dosemeters in Germany as official dosemeters, e.g. in hospitals. The concept features a net-based approach for secure data communication between readers for passive and active electronic personal dosemeters und the official personal dosimetry monitoring service(s), taking the German policies (StrISchV und RoeV in hospitals) into account. The net-based solution includes a processor controlled interface via TCP/IP connected to the dosimetry reader(s), und reader interfaces, an official interim data bank and all the necessary equipment such as PC, Raid-configuration, USV support, network connection and further details. Investigations have been started to achieve highest-level data manipulation security, data completeness und data correctness. (author)

  1. Application of beta transmission for quality assurance of TLD tape dosemeters

    Energy Technology Data Exchange (ETDEWEB)

    Nagpal, J.S.; Gupta, S.K.; Supe, S.J. (Bhabha Atomic Research Centre, Bombay (India). Div. of Radiological Protection)

    1993-03-01

    Transmission of [sup 204]Tl [beta] radiation enables measurement of differences of [+-] 2 mg/cm[sup 2] in thermoluminescent tape dosemeter thickness. This thickness variation gives rise to a maximum variation of [+-] 5% in the TL output per unit area of the dosemeters. Measurements of [beta] transmission on dosemeter samples drawn from several batches of skived tape as well as those prepared by compressing technique have given consistent results. The [beta] transmission method itself can be used for quality assurance and selection of a uniform set of dosemeters over thickness range 30-150 mg/cm[sup 2]. (author).

  2. Gene expression of Hsp70, Hsp90 and Hsp110 families in normal palate and cleft palate during mouse embryogenesis.

    Science.gov (United States)

    Zhu, Yongfei; Ren, Chuanlu; Wan, Xuying; Zhu, Yuping; Zhu, Jiangbo; Zhou, Hongyuan; Zhang, Tianbao

    2013-11-01

    Most previous studies focused on a small number of heat shock proteins (Hsps) and their relationships with embryogenesis, and the actual roles of these Hsps in normal and abnormal embryonic development remain unclear. It was found in the present systemic study that except for Grp170, whose expression was not detectable at GD18, all 19 Hsps of Hsp70, Hsp90 and Hsp110 families were expressed in the normal development of embryonic palate tissue in mice, but their expression patterns varied with different Hsps, presenting as a correlation with the developmental phases. In the treatment group by all-trans retinoic acid (atRA), the messenger RNA (mRNA) abundance of HspA1A, HspA1L, HspA8, HspA9, HspA12A, HspA12B, HspA13, HspA14, Hsp90AA1, Hsp90AB1, Grp94, Trap1, Hsp105, Hsp110 and Grp170 was higher in the palates at GD11 (the beginning of palate development), the mRNA abundance of HspA1A, HspA12A and HspA12B was higher at GD18 (before birth) and an mRNA expression peak of HspA1L, HspA8, HspA9, Hsp90AA1, Grp94, Hsp110 and Grp170 was observed at GD17. The mRNA abundance of most genes in atRA-induced cleft palates of the treatment group was different from that of the control group. Grp78, HspA14 and Hsp105 were closely associated with the normal palate development and cleft palate in mouse embryo, possibly as palate development-related genes. Except Grp170, the other genes may be closely associated with the development of mouse palates through participating in the stress response process and/or the antiapoptosis process.

  3. Personnel monitoring of radiations with thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Miano, S.C.

    1987-01-01

    The basics of personnel dosimetry technics, used by the Radiologic Protetion and Assessorie Service (SAPRA) are presented, consisting on use of thermoluminescent and CaSO 4 :Dy monitors in aggregated pellets by Teflon. The characteristics of this dosemeters, relating to the sensitivity, energetic dependence, spike temperature, characteristic emission curve, decay and light effect are shown. The thermoluminescent dosemeter measure system and the personnel monitoring system are also described. (C.G.C.) [pt

  4. Understanding differences in dose-equivalents reported by passive and electronic personal dosemeters

    International Nuclear Information System (INIS)

    Perks, Christopher A.; Burgess, Peter; Smith, David; Salasky, Mark; Yahnke, Cliff

    2008-01-01

    Full text: In a number of challenging environments, clients occasionally double badge with electronic personal dosemeters (EPDs) to ensure day-to-day management of their employees personal dose-equivalent while using passive (in our case Luxel or InLight) dosemeters for monthly monitoring for approved results for dose record keeping. In some cases there have been significant differences in the cumulative doses recorded by the EPDs and the passive dosemeters. In these circumstances the passive dosemeters usually report a higher dose than the EPD by up to a factor of two, though more commonly 1.3. In this paper we describe the differences seen between EPD and passive dosemeters (in a number of countries). We then examine the possible causes for such discrepancies by comparison with published response function data available for the EPDs and Landauer dosemeters. We have undertaken a number of experiments comparing directly a number of EPDs and passive dosemeter response to a variety of energy and complex angular geometries where the two types of dosimeter have been exposed at the same time. Recommendations will be made on the appropriate use of double badging in difficult environments and interpretation of the results. (author)

  5. Using signal ''KVANT-1'' direct-reading dosemeter for the purposes of personnel monitoring

    International Nuclear Information System (INIS)

    Glinskij, G.A.; Karasev, V.S.; Mukhin, I.E.; Chumak, V.K.

    1977-01-01

    Presented is the description of ''KVANT-1'' dosemeter for monitoring personnel doses of gamma and X radiation. The dosemeter permits to judge on the radiation intensity, to control directly the dose being accumulated, to store the reading of the dose accumulated for a necessary period of time, to obtain sound signal in case of reaching the limit of a pre-set dose. Presented are a general view, block diagram, and the discription of the dosemeter desing and operation. Advantages of the ''KVANT-1'' dosemeter are shown as compared with the conventional personnel monitoring IFK-2,3 and KID-2 dosemeters [ru

  6. A CR-39 track dosemeter for routine individual neutron monitoring

    International Nuclear Information System (INIS)

    Luszik-Bhadra, M.; Alberts, W.G.; Dietz, E.; Guldbakke, S.; Matzke, M.; d'Errico, F.

    1994-01-01

    A personal neutron dosemeter for routine individual monitoring is proposed. It is based on a CR-39 track detector covered on three separate areas by converters with different boron contents and inserted into a commercial TLD albedo dosemeter capsule. The dose readings from three areas of the electrochemically etched CR-39 detector are combined to yield a dose equivalent response which is almost independent of the incident neutron energy in the range from thermal neutrons up to 20 MeV. In addition, the dose contributions of thermal, intermediate and fast neutrons can be determined separately. Unlike the TLD albedo dosemeter, which in general requires prior in-field calibration and whose use is then restricted to that field, this dosemeter can be used in neutron fields without any knowledge of the spectral distribution with the same calibration factor. The angular dependence of the dosemeter's response has been measured and compared with that of the directional dose equivalent H'(10). The lower limit of detection is 0.15 mSv. It is possible to obtain an independent, second dose reading from the same Cr-39 detector for neutron energies above 100 keV. The dosemeter has also been successfully tested for use in accident dosimetry applying chemical etching and an optical density reading of the CR-39 detector. (author)

  7. Calibration of farmer dosemeters

    International Nuclear Information System (INIS)

    Ahmad, S.S.; Anwar, K.; Arshed, W.; Mubarak, M.A.; Orfi, S.D.

    1984-08-01

    The Farmer Dosemeters of Atomic Energy Medical Centre (AEMC) Jamshoro were calibrated in the Secondary Standard Dosimetry Laboratory (SSDL) at PINSTECH, using the NPL Secondary Standard Therapy level X-ray exposure meter. The results are presented in this report. (authors)

  8. Passive dosemeter

    International Nuclear Information System (INIS)

    Hassib, G.; Piesch, E.

    1981-01-01

    The dosemeter will be used for the detection of radon and thoron as well as their daughter products. It consists of two chambers with nuclear trace or alpha detectors. Both chambers are connected with one another at their front sides with a filter arranged in between. One of the chambers has got lateral openings, it is used as a diffusion chamber. In the other chamber exclusively radon and thoron are detected. (DG) [de

  9. About the measurements systems with pen and thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Cortes I, M.E.; Ramirez G, F.P.

    1998-01-01

    In this work it is presented dosimetric data obtained with pen and thermoluminescent dosemeters, which are used by the Occupational Exposure Personnel (OEP) of the Mexican Petroleum Institute (IMP)(1). It was marked several great characteristics as for example, the differences among units which use one and another dosemeter type. Likewise, it is given to know diverse problems that were had in the IMP at relating the data obtained with these dosemeters (which utilizes OEP) and the ICRP 60 recommendations 1990. One of the most important difficulties is to satisfy the recommended limits by ICRP, particularly those that are referring to the units and their complex calculations. With respect to the unities, the ICRP makes reference at the concepts 'dose equivalent' and 'effective dose' with the sievert unit, that the General Regulations for Radiological Safety associates with 'dose equivalent' and 'effective dose equivalent'. It was illustrated the type of dosimetric statistics which are obtained with the TLD lectures and a OEP pen dosemeter during 1997. (Author)

  10. Prediction analysis of dose equivalent responses of neutron dosemeters used at a MOX fuel facility

    International Nuclear Information System (INIS)

    Tsujimura, N.; Yoshida, T.; Takada, C.

    2011-01-01

    To predict how accurately neutron dosemeters can measure the neutron dose equivalent (rate) in MOX fuel fabrication facility work environments, the dose equivalent responses of neutron dosemeters were calculated by the spectral folding method. The dosemeters selected included two types of personal dosemeter, namely a thermoluminescent albedo neutron dosemeter and an electronic neutron dosemeter, three moderator-based neutron survey meters, and one special instrument called an H p (10) monitor. The calculations revealed the energy dependences of the responses expected within the entire range of neutron spectral variations observed in neutron fields at workplaces. (authors)

  11. Dose equivalent response of personal neutron dosemeters as a function of angle

    International Nuclear Information System (INIS)

    Tanner, J.E.; McDonald, J.C.; Stewart, R.D.; Wernli, C.

    1997-01-01

    The measured and calculated dose equivalent response as a function of angle has been examined for an albedo-type thermoluminescence dosemeter (TLD) that was exposed to unmoderated and D 2 O-moderated 252 Cf neutron sources while mounted on a 40 x 40 15 cm 3 polymethylmethacrylate phantom. The dosemeter used in this study is similar to many neutron personal dosemeters currently in use. The detailed construction of the dosemeter was modelled, and the dose equivalent response was calculated, using the MCNP code. Good agreement was found between the measured and calculated values of the relative dose equivalent angular response for the TLD albedo dosemeter. The relative dose equivalent angular response was also compared with the values of directional and personal dose equivalent as a function of angle published by Siebert and Schuhmacher. (author)

  12. Evaluation of film dosemeters by linear programming

    International Nuclear Information System (INIS)

    Kragh, P.; Nitschke, J.

    1992-01-01

    An evaluation method for multi-component dosemeters is described which uses linear programming in order to decrease the dependence on energy and direction. The results of this method are more accurate than those obtained with the evaluation methods so far applied in film dosimetry. In addition, systematic errors can be given when evaluating individual measurements. Combined linear programming, as a special case of the presented method, is described taking a film dosemeter of particular type as an example. (orig.) [de

  13. Dosemeter calibration in X-ray and in cobalt-60

    International Nuclear Information System (INIS)

    Silva, T.A. da

    1988-01-01

    Some tests about quality security for clinical dosemeter calibration in secondary standard dosimetry laboratory are described. The tests in gama calibration system, in X-ray calibration, in secondary standard dosimeter, in the dosemeter that will be calibrated, during the calibration and after the calibration are shown. (C.G.C.) [pt

  14. Characterization of the personal thermoluminescent dosemeter of LiF: Mg, Ti + Ptfe

    International Nuclear Information System (INIS)

    Azorin N, J.; Gutierrez C, A.; Gonzalez M, P.

    1991-01-01

    The objective of this work is to characterize the thermoluminescent dosemeters taken place in the laboratory in form of pellets of LiF: Mg, Ti + Ptfe like personal dosemeters, subjecting them to the operation tests proposed by the international standards and comparing them with the TLD-100, the Tl dosemeter more used at the moment for personal dosimetry

  15. The influence of the energy distribution of workplace fields on neutron personal dosemeter reading

    International Nuclear Information System (INIS)

    Tanner, R.J.; Thomas, D.J.; Bartlett, D.T.; Hager, L.G.; Horwood, N.A.

    2002-01-01

    Variations in the energy dependence of response of neutron personal dosemeters cause systematic errors in the readings obtained in workplace fields. The magnitude of these errors has been determined theoretically by folding measured and calculated workplace energy distributions with dosemeter response functions, to determine the response of a given personal dosemeter in that field. These results have been analysed with consideration of the dosemeter response to various calibration spectra, and with reference to different workplaces. The dosemeters in the study are discussed in terms of the workplaces for which they can be suitably calibrated. Deficiencies in the published neutron energy distributions are identified

  16. Dosimetric of extremities with Dosemeters thermoluminescent in Cuba

    International Nuclear Information System (INIS)

    Molina Perez, D.; Diaz Bernal, E.; Vera Alonso, L.

    1998-01-01

    From final of the year 1995 in the CPHR implement the service of monitoring of the extremities using Dosemeter thermoluminescent (TL). The dosemeter consists on a metallic ring with a circular hole where a detector of LiF:Mg,Ti is placed (model JR1152C) of 5x5x0.9 mm 3 , covered by a fine layer of polyethylene. In the work the characteristic dosimetric as of the dosemeter is studied it satisfies the main requirements for their use in the monitoring from the exhibition to radiation photonic of the extremities. The doses are also presented registered during the first two years of operation of the service. The results obtained until the moment point out to you practice them of nuclear medicine, radiotherapy and production of substances radioactive how as of more contribution

  17. Automated read-out of thermoluminescence dosemeters in a centralized individual monitoring service

    International Nuclear Information System (INIS)

    Toivonen, M.

    The organizational problems in maintaining centralized individual monitoring service with erasable and re-usable dosemeters are evaluated. Design criteria for an automated thermoluminescence reader are laid down. It is characteristic for the planning of the monitoring system that the issuing of dosemeters can be arranged without having two dosemeters for each worker. A home made reader designed to fullfil these criteria is presented. The use of a standard barcode and a standard optical barcode reader in identification of dosemeters is described. A method of using a minicomputer in preparing the self-fastening identification labels, in printing mailing lists and in printing results is described

  18. A study of the irradiation temperature coefficient for L-alanine and DL-alanine dosemeters

    International Nuclear Information System (INIS)

    Desrosiers, M. F.; Lin, M.; Cooper, S. L.; Cui, Y.; Chen, K.

    2006-01-01

    Alanine dosimetry is now well established both as a reference and routine dosemeter for industrial irradiation processing. Accurate dosimetry under the relatively harsh conditions of industrial processing requires a characterisation of the parameters that influence the dosemeter response. The temperature of the dosemeter during irradiation is a difficult quantity to measure so that the accuracy of the temperature coefficient that governs the dosemeter response becomes a critical factor. Numerous publications have reported temperature coefficients for several types of alanine dosemeters. The observed differences in the measured values were commonly attributed to the differences in the polymer binder or the experimental design of the measurement. However, the data demonstrated a consistent difference in the temperature coefficients between L-alanine and DL-alanine. Since there were no commonalities in the dosemeter composition or the measurement methods applied, a clear conclusion is not possible. To resolve this issue, the two isomeric forms of alanine dosemeters were prepared and irradiated in an identical manner. The results indicated that the DL-alanine temperature coefficient is more than 50% higher than the L-alanine temperature coefficient. (authors)

  19. Characteristics of dosemeter types for skin dose measurements in practice

    International Nuclear Information System (INIS)

    Van, D. J.; Bosmans, H.; Marchal, G.; Wambersie, A.

    2005-01-01

    A growing number of papers report deterministic effects in the skin of patients who have undergone interventional radiological procedures. Dose measurements, and especially skin dose measurements, are therefore increasingly important. Methods and acceptable dosemeters are, however, not clearly defined. This paper is the result of a literature overview with regard to assessing the entrance skin dose during radiological examinations by putting a dosemeter on the patient's skin. The relevant intrinsic characteristics, as well as some examples of clinical use of the different detector types, are presented. In this respect, thermoluminescence, scintillation, semiconductor and film dosemeters are discussed and compared with respect to their practical use. (authors)

  20. A gamma/neutron-discriminating, Cooled, Optically Stimulated Luminescence (COSL) dosemeter

    International Nuclear Information System (INIS)

    Eschbach, P.A.; Miller, S.D.

    1992-07-01

    The Cooled Optically Stimulated Luminescence (COSL) of CaF 2 :Mn (grain sizes from 0.1 to 100 microns) powder embedded in a hydrogenous matrix is reported as a function of fast-neutron dose. When all the CaF 2 :Mn grains are interrogated at once, the COSL plastic dosemeters have a minimum detectable limit of 1 cSv fast neutrons; the gamma component from the bare 252 cf exposure was determined with a separate dosemeter. We report here on a proton-recoil-based dosemeter that generates pulse height spectra, much like the scintillator of Hornyak, (2) to provide information on both the neutron and gamma dose

  1. Numerical and experimental results of the operational neutron dosemeter 'Saphydose-N'

    International Nuclear Information System (INIS)

    Lahaye, T.; Chau, Q.; Menard, S.; Ndontcheung-Moyo, M.; Bolognese-Milsztajn, T.; Rannou, A.

    2004-01-01

    Since 1993, the Inst. for Radiological Protection and Nuclear Safety (IRSN) has lead, in association with Electricite de France (EDF), a R and D study of a neutron personal electronic dosemeter. This dosemeter, called 'Saphydose-N', is manufactured by the SAPHYMO company. This paper presents first the optimisation of some detector components using Monte Carlo calculations, and second the test of the manufactured Saphydose-N under radiation following the IEC 1323 standard's recommendations for active personal neutron dosemeters. The measurements with the manufactured dosemeter were performed on the one hand at PTB (Physikalisch-Technische Bundesanstalt) in mono-energetic neutron fields and, on the other hand at IRSN in neutron fields generated by a thermal facility (SIGMA), radionuclide ISO sources and a realistic spectrum (CANEL/T400). The manufactured dosemeter Saphydose-N was also tested during measurement campaigns of the European programme EVIDOS ('Evaluation of Individual Dosimetry in Mixed Neutron and Photon Radiation Fields') at different nuclear workplaces. The study showed that Saphydose-N complies with the recommendations of standard IEC 1323 and can be used at any workplace with no previous knowledge of the neutron field characteristics. (authors)

  2. The right choice: extremity dosemeter for different radiation fields

    International Nuclear Information System (INIS)

    Brasik, N.; Stadtmann, H.; Kindl, P.

    2005-01-01

    Full text: Measurements of weakly penetrating radiation in personal dosimetry present problems in the design of suitable detectors and in the interpretation of their readings. For the measurement of the individual beta radiation dose, personal dosemeter for the fingers/tips are required. In general, the dosemeters currently used for personal monitoring of beta and low energy photon doses suffer from an energy threshold problem because the detector and/or the filter are too thick. TLDs of a standard thickness can seriously underestimate personal skin doses, especially in external fields of weakly penetrating radiation fields. LiF:Mg, Cu, P is a promising TL material which allows the production of thin detectors with sufficient sensitivity. Dosimetric properties of two different types of extremity dosemeters, designed to measure the personal dose equivalent Hp(0.07), have been compared: LiF:Mg, Ti (TLD100) and LiF:Mg, Cu, P (TLD700H). The first one consists of 100 mg.cm -2 LiF:Mg, Ti (TLD 100) chip and a 35mg. cm -2 cap, the other consists of a 7mg. cm -2 layer of LiF:Mg, Cu, P (TLD-700H) powder and a 5mg. cm -2 cap. The evaluation was done in two steps: performance tests (ISO-12794) and measurements in real workplaces. In the first step type test results for beta calibration were compared. In addition calibration for low energy photon radiation according to ISO 4037-3 was carried out. In the second step, simultaneous measurements with both types of dosemeters were performed at workplaces, where radiopharmaceuticals containing different radioisotopes are prepared and applied. Practices in these fields are characterized by handling of high activities at very small distances between source and skin. The results from the comparison of the two dosemeter types are presented and analyzed with respect to different radiation fields. Experiments showed a satisfactory sensitivity for the thinner dosemeter (TLD 700H) for detecting beta radiation at protection levels and a good

  3. The NRPB nuclear emission dosemeter

    International Nuclear Information System (INIS)

    Bartlett, D.T.; Bird, T.V.; Miles, J.C.H.

    1980-03-01

    The NRPB nuclear emulsion dosemeter is designed such that the thermal neutron response is similar to the fast neutron response. This report gives details of the dependence of response on incident neutron energy and on neutron angle of incidence. (author)

  4. Evaluation of personal dosemeters and comparative measurements performed by PTB in the years 1979 through 1984. Pt. 1

    International Nuclear Information System (INIS)

    Boehm, J.; Buchholz, G.

    1986-01-01

    Comparison measurements of the official individual dosemeters performed in the PTB from 1979 to 1984 are described. Also a number of other, unofficial individual dosemeters participated. The performance of the comparison measurements and the types of the individual dosemeters are described. Tables show the values measured with the film dosemeters, with film and TLD dosemeters, and TLD dosemeters as well as dosimetric probes for whole-body and partial body dose measurement. (DG) [de

  5. Application of chemical dosemeters during the irradiation of agricultural products

    Energy Technology Data Exchange (ETDEWEB)

    Kovacs, A; Stenger, V; Foeldiak, G [Magyar Tudomanyos Akademia, Budapest. Izotopintezete

    1983-09-01

    The joint recommedation by the FAO, WHO and IAEA in 1981 proposed the unrestricted permission of food irradiation under the dose value of 10 kGy (1 Mrd). The chemical dosemeters presented in the paper cover the dose range of 30 Gy to 1 MGy for use to food irradiation safety measurements. The Fricke dosemeter was used in the 50-400 Gy range at radappertization operations of onion, poppy and potato. The alcoholic chlorobenzene dosemeter with oscillometric analysis was applied successfully at low (0.4-4 kGy) ranges, primarily for irradiation dose monitoring of fruits, vegetables, refrigerated poultry etc. The conductometry could be used for dosimetry in the range of 60 Gy to 1 MGy.

  6. Whey protein hydrolysate enhances HSP90 but does not alter HSP60 and HSP25 in skeletal muscle of rats.

    Directory of Open Access Journals (Sweden)

    Carolina Soares Moura

    Full Text Available Whey protein hydrolysate (WPH intake has shown to increase HSP70 expression. The aim of the present study was to investigate whether WPH intake would also influences HSP90, HSP60 and HSP25 expression, as well as associated parameters. Forty-eight male Wistar rats were divided into sedentary (unstressed and exercised (stressed groups, and were fed with three different sources of protein: whey protein (WP, whey protein hydrolysate (WPH and casein (CAS as a control, based on the AIN93G diet for 3 weeks. WPH intake increased HSP90 expression in both sedentary and exercised animals compared to WP or CAS, however no alteration was found from exercise or diet to HSP60 or HSP25. Co-chaperone Aha1 and p-HSF1 were also increased in the exercised animals fed with WPH in comparison with WP or CAS, consistent with enhanced HSP90 expression. VEGF and p-AKT were increased in the WPH exercised group. No alteration was found in BCKDH, PI3-Kinase (p85, GFAT, OGT or PGC for diet or exercise. The antioxidant system GPx, catalase and SOD showed different responses to diet and exercise. The data indicate that WPH intake enhanced factors related to cell survival, such as HSP90 and VEGF, but does not alter HSP60 or HSP25 in rat skeletal muscle.

  7. Solid thermoluminescent dosemeter of sodium tetraborate and brazilian fluorite sensible to thermic neutrons

    International Nuclear Information System (INIS)

    Fratin, L.; Cruz, M.T. da

    1987-01-01

    The production of solid thermoluminescent dosemeters sensible to thermic neutrons is described. The stages of the production are described: vitrification of sodium tetraborate, mixture and cold pressing, syntherization. The obtention of a CaF 2 : natural dosemeter with NaCl which presents sensibility to gamma radiation similar to CaF 2 : natural dosemeter with Na 2 B 4 O 7 is studied. (M.A.C.) [pt

  8. Plasmodium falciparum Hsp70-z, an Hsp110 homologue, exhibits independent chaperone activity and interacts with Hsp70-1 in a nucleotide-dependent fashion.

    Science.gov (United States)

    Zininga, Tawanda; Achilonu, Ikechukwu; Hoppe, Heinrich; Prinsloo, Earl; Dirr, Heini W; Shonhai, Addmore

    2016-05-01

    The role of molecular chaperones, among them heat shock proteins (Hsps), in the development of malaria parasites has been well documented. Hsp70s are molecular chaperones that facilitate protein folding. Hsp70 proteins are composed of an N-terminal nucleotide binding domain (NBD), which confers them with ATPase activity and a C-terminal substrate binding domain (SBD). In the ADP-bound state, Hsp70 possesses high affinity for substrate and releases the folded substrate when it is bound to ATP. The two domains are connected by a conserved linker segment. Hsp110 proteins possess an extended lid segment, a feature that distinguishes them from canonical Hsp70s. Plasmodium falciparum Hsp70-z (PfHsp70-z) is a member of the Hsp110 family of Hsp70-like proteins. PfHsp70-z is essential for survival of malaria parasites and is thought to play an important role as a molecular chaperone and nucleotide exchange factor of its cytosolic canonical Hsp70 counterpart, PfHsp70-1. Unlike PfHsp70-1 whose functions are fairly well established, the structure-function features of PfHsp70-z remain to be fully elucidated. In the current study, we established that PfHsp70-z possesses independent chaperone activity. In fact, PfHsp70-z appears to be marginally more effective in suppressing protein aggregation than its cytosol-localized partner, PfHsp70-1. Furthermore, based on coimmunoaffinity chromatography and surface plasmon resonance analyses, PfHsp70-z associated with PfHsp70-1 in a nucleotide-dependent fashion. Our findings suggest that besides serving as a molecular chaperone, PfHsp70-z could facilitate the nucleotide exchange function of PfHsp70-1. These dual functions explain why it is essential for parasite survival.

  9. Thermoluminescence sensitivity variations in LiF PTFE dosemeters incurred by improper handling procedures

    CERN Document Server

    Mason, E W; MacKinlay, Alistair F; Saunders, D

    1975-01-01

    A systematic study of some anomalous darkening effects and thermoluminescence sensitivity variations observed in LiF:PTFE thermoluminescent dosemeters is described. Various likely causes of such effects have been investigated. The manufacturer's recommended cleaning procedures have been found to be inadequate and, in some cases, have been found to actually promote discolouration of the dosemeters. Recommendations are given for the successful use of LiF:PTFE thermoluminescent dosemeters in personal dosimetry.

  10. EURADOS intercomparison 2012 for neutron dosemeters

    International Nuclear Information System (INIS)

    Fantuzzi, E.; Chevallier, M.A.; Cruz-Suarez, R.; Luszik-Bhadra, M.; Mayer, S.; Thomas, D.J.; Tanner, R.; Vanhavere, F.

    2014-11-01

    EURADOS, within the work performed by Working Group 2 - Harmonization of Individual Monitoring in Europe, has started a self-sustained programme of regular intercomparisons and has successfully executed three intercomparisons for whole body photon dosemeters (IC2008, IC2010, IC2012) and one intercomparison for extremity dosemeters for photon and beta fields (IC2009). In 2012, the EURADOS intercomparison IC2012n was launched for personal neutron dosemeters routinely used to measure personal dose equivalent, Hp(10), in individual monitoring. No systems under development were allowed to participate. IC2012n was carried out by a EURADOS nominated Organization Group (OG) consisting of: Marie- Anne Chevallier (IRSN, F), Rodolfo Cruz-Suarez (IAEA, UN-Vienna), Marlies Luszik-Bhadra (PTB, D), Sabine Mayer (PSI, CH), David J. Thomas (NPL, UK), Rick Tanner (PHE, UK), Filip Vanhavere (SCK-CEN, B) led by a Coordinator, Elena Fantuzzi (ENEA, I). 31 participants registered for the comparison, with 34 dosimetry systems. In total 816 dosemeters were irradiated in selected neutron fields on an ISO slab phantom. The irradiations were performed at 2 European accredited laboratories which are both National Primary Metrology Laboratories for ionizing radiation: NPL (National Physical Laboratory, UK) and PTB (Physikalisch-Technische Bundesanstalt, D). All irradiations were carried out according to the irradiation plan developed by the OG. The overall results show that most, although not all, dosimetric systems perform acceptably well (within a factor of 2) for irradiations with a bare radionuclide source ( 252 Cf at 0 ), whilst more than half of the systems underestimate the reference value for irradiations from non-normal angles of incidence irradiations ( 252 Cf at 45 ) or for simulated workplace fields ( 252 Cf(D 2 O) or 252 Cf source behind a shadow cone). The performance for 250 keV mono-energetic neutron irradiations varies mainly reflecting the detection principle on which the

  11. Measurement of gamma radiation doses at the RA reactor by thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Prokic, M.

    1974-01-01

    This paper presents the procedures and gamma radiation doses measured at the exit from the horizontal experimental channel HK-5, vertical experimental channel VK-5 and in the thermal column of the RA reactor in Vinca. Measurement of gamma radiation dose in the mixed intense gamma and neutron radiation field was done by two types of thermoluminescent dosemeters, LiF (TLD-700) and CaF 2 (TLD-08). Gamma dose in the VK-5 was measured in the air and on the bottle filled with tissue-equivalent solution. Increase of the dose on the surface of the bottle was 2.3 compared to the gamma dose value in the air. Correction for the influence of neutrons having different energies was done by using the known sensitivity values of both TL dosemeter types for thermal, intermediate and fast neutrons. Results showed that the TLD-700 dosemeter contains 5 time more Li-6 isotopes (0.035%) than the declared value causing increased neutron sensitivity of this dosemeter. This paper includes numerical sensitivity data for neutrons of different energies for both types of TL dosemeters. Neutron sensitivity values for TLD-700 are related to LiF with 0.035% of Li-6 isotope. Result of measurement have also shown that the CaF 2 :Mn (TLD-08) thermoluminescent dosemeter is more suitable for gamma radiation dose measurements in mixed n-gamma fields with intensive neutron fluxes due to lower neutron sensitivity compared to TLD-700 [sr

  12. Solid thermoluminescent dosemeter of sodium tetraborate and brazilian fluorite sensible to thermal neutrons

    International Nuclear Information System (INIS)

    Fratin, L.; Cruz, M.T. da

    1987-01-01

    A solid termoluminescent dosemeter of sodium tetraborate and brazilian fluorite sensible to thermal neutrons is described. The nuclears reactions 1) 10 B + n → 7 Li + He + Q1 (6,1%) where: Q1=2,79 MeV and Eα1 = 1,758 MeV and 2) 10 B + n → 7 Li* + 4 He + Q2 (93,9%) where: Q2 = 2,316 MeV and E2α 2 = 1,474 MeV are responsible by the thermoluminescent response of the thermal neutrons dosemeters. The stages in the fabrication process of this dosemeter of which are:1) sodium tetraborate vitrification, 2) mixture and pressing 3) sintering are cited. The obtainment of a natural fluorite dosemeter with sodium chloride is also shown. (C.G.C.) [pt

  13. Radiological environmental monitoring with LiF-700-H dosemeters

    International Nuclear Information System (INIS)

    Scarnichia, E.; Levanon, I.; Andres, P.; Miani, C.; Ramirez, S.

    2011-10-01

    Since 2008 a radiological environmental monitoring with LiF-700-H has been carried out as a result of increasing the Ra-6 research reactor core power. The information obtained is used to evaluate and to quantify analytically the air kerma rate, the fading and the associated uncertainty by developing software tools (deconvolution and uncertainty algorithms). LiF-700-H dosemeters were chosen because of their high sensitivity to low air kerma rates. They show a very good stability and a negligible fading for two-month working periods. The air kerma rate detection limit (based on the 3σ criterion) during these working periods is about 0.4 n Gy/h. Air kerma rates of about 70 n Gy/h are measured with this detection limit. Following the Nist guidelines, an algorithm was developed in order to find the associated uncertainty. It considers several aspects, such as the source activity decay, distance source-dosemeter during the calibration procedure, irradiation time, calibration factor, dosemeter readout, dosemeter sensitivity, TLD reader stability and fading. The associated uncertainty is found to be about 25% for a 95% confidence interval (k = 2.025), which can be considered acceptable when taking into account the very low air kerma rates estimated. The LiF-700-H response to different energies and its relationship with climate changes over the calendar year are planned as future tasks. (Author)

  14. Development and testing of a thermoluminescent dosemeter for mixed neutron-photon-beta radiation fields

    International Nuclear Information System (INIS)

    Zummo, J.J.; Liu, J.C.

    1998-08-01

    A new four-element thermoluminescent (TL) dosemeter and dose evaluation algorithm have been developed and tested to better characterize personnel exposure in mixed neutron-photon-beta radiation fields. The prototype dosemeter is based on a commercially available TL card (with three LiF-7 chips and one LiF-6 chip) and modified filtration elements. The new algorithm takes advantage of the high temperature peak characteristics of the LiF-6 element to better quantify the neutron dose component. The dosemeter was tested in various radiation fields, consisting of mixtures of two radiation types typically used for dosemeter performance testing, as well as mixtures of three radiation types to simulate possible exposure conditions. The new dosemeter gave superior performance, based on the tolerance levels, when using the new algorithm as compared to a conventional algorithm that did not use the high temperature peak methodology. The limitations and further improvements are discussed

  15. Validation of response simulation methodology of Albedo dosemeter

    International Nuclear Information System (INIS)

    Freitas, B.M.; Silva, A.X. da

    2016-01-01

    The Instituto de Radioprotecao e Dosimetria developed and runs a neutron TLD albedo individual monitoring service. To optimize the dose calculation algorithm and to infer new calibration factors, the response of this dosemeter was simulated. In order to validate this employed methodology, it was applied in the simulation of the problem of the QUADOS (Quality Assurance of Computational Tools for Dosimetry) intercomparison, aimed to evaluate dosimetric problems, one being to calculate the response of a generic albedo dosemeter. The obtained results were compared with those of other modeling and the reference one, with good agreements. (author)

  16. Calibration of a scintillation dosemeter for beta rays using an extrapolation ionization chamber

    International Nuclear Information System (INIS)

    Hakanen, A.T.; Sipilae, P.M.; Kosunen, A.

    2004-01-01

    A scintillation dosemeter is calibrated for 90 Sr/ 90 Y beta rays from an ophthalmic applicator, using an extrapolation ionization chamber as a reference instrument. The calibration factor for the scintillation dosemeter agrees with that given by the manufacturer of the dosemeter within ca. 2%. The estimated overall uncertainty of the present calibration is ca. 6% (2 sd). A calibrated beta-ray ophthalmic applicator can be used as a reference source for further calibrations performed in the laboratory or in the hospital

  17. Measurements of environmental gamma-ray spectra using a multi-element TL dosemeter

    International Nuclear Information System (INIS)

    Furuta, Sadaaki; Boetter-Jensen, L.; Nielsen, S.P.

    1986-12-01

    A method to estimate the energy distribution and dose of environmental gamma radiation was developed using a multielement TL dosemeter. Experimentally obtained energy responses from a multi-element TL dosemeter with different kinds of filters were used to calculate the energy distribution and related dose by the SAND-II computer code. The code was originally developed to estimate the neutron flux using a multiple foil activation method. Measurements were made at several locations with the multi-element TL dosemeter and comparisons were made with results from a NaI(Tl) scintillation detector and a high-pressure ionization chamber. (author)

  18. EURADOS intercomparison 2012 for neutron dosemeters

    Energy Technology Data Exchange (ETDEWEB)

    Fantuzzi, E. [ENEA-Radiation Protection Institute, Bologna (Italy); Chevallier, M.A. [Institut de Radioprotection et de Surete Nucleaire (IRSN), Fontenay-aux-Roses (France); Cruz-Suarez, R. [International Atomic Energy Agency, Vienna (Austria); Luszik-Bhadra, M. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Mayer, S. [Paul Scherrer Institute (PSI), Villigen (Switzerland); Thomas, D.J. [National Physical Laboratory (NPL), Teddington (United Kingdom); Tanner, R. [Public Health England, Oxon (United Kingdom); Vanhavere, F. [SCK-CEN, Belgian Nuclear Research Centre, Mol (Belgium)

    2014-11-15

    EURADOS, within the work performed by Working Group 2 - Harmonization of Individual Monitoring in Europe, has started a self-sustained programme of regular intercomparisons and has successfully executed three intercomparisons for whole body photon dosemeters (IC2008, IC2010, IC2012) and one intercomparison for extremity dosemeters for photon and beta fields (IC2009). In 2012, the EURADOS intercomparison IC2012n was launched for personal neutron dosemeters routinely used to measure personal dose equivalent, Hp(10), in individual monitoring. No systems under development were allowed to participate. IC2012n was carried out by a EURADOS nominated Organization Group (OG) consisting of: Marie- Anne Chevallier (IRSN, F), Rodolfo Cruz-Suarez (IAEA, UN-Vienna), Marlies Luszik-Bhadra (PTB, D), Sabine Mayer (PSI, CH), David J. Thomas (NPL, UK), Rick Tanner (PHE, UK), Filip Vanhavere (SCK-CEN, B) led by a Coordinator, Elena Fantuzzi (ENEA, I). 31 participants registered for the comparison, with 34 dosimetry systems. In total 816 dosemeters were irradiated in selected neutron fields on an ISO slab phantom. The irradiations were performed at 2 European accredited laboratories which are both National Primary Metrology Laboratories for ionizing radiation: NPL (National Physical Laboratory, UK) and PTB (Physikalisch-Technische Bundesanstalt, D). All irradiations were carried out according to the irradiation plan developed by the OG. The overall results show that most, although not all, dosimetric systems perform acceptably well (within a factor of 2) for irradiations with a bare radionuclide source ({sup 252}Cf at 0 ), whilst more than half of the systems underestimate the reference value for irradiations from non-normal angles of incidence irradiations ({sup 252}Cf at 45 ) or for simulated workplace fields ({sup 252}Cf(D{sub 2}O) or {sup 252}Cf source behind a shadow cone). The performance for 250 keV mono-energetic neutron irradiations varies mainly reflecting the detection

  19. Thermoluminescence dosemeter for personal dose equivalent assessment

    International Nuclear Information System (INIS)

    Silva, T.A. da; Rosa, L.A.R. da; Campos, L.L.

    1995-01-01

    The possibility was investigated of utilising a Brazilian thermoluminescence individual dosemeter, usually calibrated in terms of photon dose equivalent, for the assessment of the personal dose equivalent, H p (d), at depths of 0.07 and 10 mm. The dosemeter uses four CaSO 4 :Dy thermoluminescent detectors, between different filters, as the sensitive materials. It was calibrated in gamma and X radiation fields in the energy range from 17 to 1250 keV. Linear combinations of the responses of three detectors, in this energy range, allow the evaluation of H p (0.07) and H p (10), for radiation incidence angles varying from 0 to 60 degrees, with an accuracy better than 35%. The method is not applicable to mixed photon-beta fields. (author)

  20. On the calibration of radiotherapy dosemeters in Australia

    International Nuclear Information System (INIS)

    Huntley, R.; Kotler, L.; Webb, D.

    2000-01-01

    Full text: Dosemeters for external beam radiotherapy are calibrated in Australia by ARPANSA, against the national primary standards of exposure and absorbed dose. The primary standards are free air chambers for exposure at low and medium energy X-rays, a graphite cavity chamber for exposure at 60 Co, and a graphite calorimeter for absorbed dose at 60 Co and high energy (MV) X -rays. Radiotherapy dosemeters are calibrated against these standards using a well documented formalism to provide calibration factors suitable for use with dosimetry protocols. A dosemeter usually comprises an ionization chamber connected to an independent electrometer. These are calibrated separately if possible. A combined calibration factor is reported together with the electrometer calibration factor (sensitivity). The dosimetry protocol used in radiotherapy centres in Australia and New Zealand is currently the simplified version of the IAEA TRS277 protocol, published by the New Zealand NRL and recommended by the ACPSEM. This protocol requires the use of an exposure or air kerma calibration factor at 60 Co (Nx or Nk) to evaluate the absorbed dose to air calibration factor N D . The chamber is then placed in a water phantom with its centre displaced from the reference point by p eff . ARPANSA can also supply calibration factors in absorbed dose to water (N D,w ), as required as input to the new IAEA CoP. If an absorbed dose to water calibration factor is used by the radiotherapy centre, the chamber should be placed with its centre at the reference point in the water phantom. ARPANSA has for some years coordinated the participation of Australian radiotherapy centres in the IAEA TLD Quality Audit service. Note that this service does not represent a calibration and should not be referred to as such. The only calibration is that provided by ARPANSA for a reference dosemeter at each radiotherapy centre. As soon as the ANSTO SSDL is operational, calibrations of reference dosemeters will also be

  1. How do hospital sterilisation procedures affect the response of personal extremity rings and of eye lens TL dosemeters?

    International Nuclear Information System (INIS)

    Kopec, Renata; Bubak, Anna; Budzanowski, Maciej; Sas-Bieniarz, Anna; Szumska, Agnieszka

    2016-01-01

    Stringent standards of hygiene must be applied in medical institutions, especially at operating blocks or during interventional radiology procedures. Medical equipment, including personal dosemeters that have to be worn by medical staff during such procedures, needs therefore to be sterilised. In this study, the effect of various sterilisation procedures has been tested on the dose response of extremity rings and of eye lens dosemeters in which thermoluminescent (TL) detectors (of types MTS-N and MCP-N, respectively) are used. The effects of medical sterilisation procedures were studied: by chemicals, by steam or by ultraviolet (UV), on the dose assessment by extremity rings and by eye lens dosemeters. Since it often happens that a dosemeter is accidentally machine-washed together with protective clothing, the effect of laundering on dose assessment by these dosemeters was also tested. The sterilisation by chemicals is mostly safe for TL detectors assuming that the dosemeters are waterproofed. Following sterilisation by water vapour, the response of these dosemeters diminished by some 30 %, irrespectively of the period of sterilisation; therefore, this method is not recommended. UV sterilisation can be applied to EYE-D TM eye lens dosemeters if their encapsulation is in black. The accidental dosemeter laundry in a washing machine has no impact on measured dose. (authors)

  2. C-program LINOP for the evaluation of film dosemeters by linear optimization. User manual

    International Nuclear Information System (INIS)

    Kragh, P.

    1995-11-01

    Linear programming results in an optimal measuring value for film dosemeters. The Linop program was developed to be used for linear programming. The program permits the evaluation and control of film dosemeters and of all other multi-component dosemeters. This user manual for the Linop program contains the source program, a description of the program and installation and use instructions. The data sets with programs and examples are available upon request. (orig.) [de

  3. Development of radiophotometric dosemeters of high sensitivity using plastic scintillators as light intensifiers

    International Nuclear Information System (INIS)

    Mesquita, C.H. de; Hamada, M.M.

    1987-01-01

    The use of rectangular plates of plastic scintillators as film holders in conventional photographic dosemeters is reported. The efficiency of their use as light converters for increase the sensitivity of these dosemeters are studied. (M.A.C.) [pt

  4. Thermoluminescent dosemeters of CaSO4: Dy + Teflon

    International Nuclear Information System (INIS)

    Campos, L.L.

    1989-01-01

    The development of a pellet dosemeter of CaSO 4 : Dy + Teflon at the Dosimetric Materials Production Laboratory - IPEN/Brazilian CNEN-SP is presented. The pellets were produced by cold pressing and sintering a mixture of CaSO 4 : Dy and Teflon powders. The pellet characteristics from the point of view of dosimetry. A filter combination providing an energy independent response from 20 KeV to 1,25 MeV was obtained. The dosemeter consists of three pellets sealed between two thin plastic sheets and placed under plastic and lead filters. The combination of these three filters allows to determine the energy of an unknown source. (author) [pt

  5. Chaperone-Mediated Regulation of Choline Acetyltransferase Protein Stability and Activity by HSC/HSP70, HSP90, and p97/VCP

    Directory of Open Access Journals (Sweden)

    Trevor M. Morey

    2017-12-01

    Full Text Available Choline acetyltransferase (ChAT synthesizes the neurotransmitter acetylcholine in cholinergic neurons, and mutations of this enzyme are linked to the neuromuscular disorder congenital myasthenic syndrome (CMS. One CMS-related mutation, V18M, reduces ChAT enzyme activity and cellular protein levels, and is located within a highly-conserved N-terminal proline-rich motif at residues 14PKLPVPP20. We showed previously that disruption of this proline-rich motif by either proline-to-alanine mutation (P17A/P19A or mutation of residue Val18 (V18M enhances ubiquitination and degradation of these mutant ChAT proteins expressed in cholinergic SN56 cells by an unknown mechanism. In this study, using proximity-dependent biotin identification (BioID, co-immunoprecipitation and in situ proximity-ligation assay (PLA, we identified the heat shock proteins (HSPs HSC/HSP70 and HSP90 as novel ChAT protein-interactors. These molecular chaperones are well-known for promoting the folding and stabilization of cellular proteins. Thus, we found that inhibition of HSPs by treatment of cells with either the HSC/HSP70 inhibitors 2-phenylethynesulfonamide (PES or VER-155008, or the HSP90 inhibitor 17-AAG reduced cellular ChAT activity and solubility, and enhanced the ubiquitination and proteasome-dependent loss of ChAT protein. Importantly, the effects of HSP inhibition were greater for mutant ChAT proteins (P17A/P19A-ChAT and CMS-related V18M- and A513T-ChAT compared to wild-type ChAT. HSPs can promote ubiquitination and degradation of terminally misfolded proteins through cooperative interaction with the E3 ubiquitin ligase CHIP/Stub1, and while we show that ChAT interacts with CHIP in situ, siRNA-mediated knock-down of CHIP had no effect on either wild-type or mutant ChAT protein levels. However, inhibition of the endoplasmic reticulum (ER- and HSP-associated co-chaperone p97/VCP prevented degradation of ubiquitinated ChAT. Together, these results identify novel mechanisms

  6. Neutron dosemeter responses in workplace fields and the implications of using realistic neutron calibration fields

    International Nuclear Information System (INIS)

    Thomas, D.J.; Horwood, N.; Taylor, G.C.

    1999-01-01

    The use of realistic neutron calibration fields to overcome some of the problems associated with the response functions of presently available dosemeters, both area survey instruments and personal dosemeters, has been investigated. Realistic calibration fields have spectra which, compared to conventional radionuclide source based calibration fields, more closely match those of the workplace fields in which dosemeters are used. Monte Carlo simulations were performed to identify laboratory systems which would produce appropriate workplace-like calibration fields. A detailed analysis was then undertaken of the predicted under- and over-responses of dosemeters in a wide selection of measured workplace field spectra assuming calibration in a selection of calibration fields. These included both conventional radionuclide source calibration fields, and also several proposed realistic calibration fields. The present state of the art for dosemeter performance, and the possibilities of improving accuracy by using realistic calibration fields are both presented. (author)

  7. A personal dosemeter of radon daughter products

    International Nuclear Information System (INIS)

    Burian, I.; Richter, M.; Ochec, J.; Dohnal, J.

    1990-01-01

    The OD 88 personal dosemeter for radon daughter products uses an alpha particle track detector and is of active type, with forced air aspiration through the detecting system. The pumping device consists of a miniature membrane pump and an electronic speed controller. The air flow rate is little affected by normal changes in supply voltage and/or pneumatic resistance of the pump circuit. The dosemeter is embedded in a miner's lamp and is fed from its accumulator battery. The pumping device is activated as the lamp is taken out of the charger and deactivated as it is slid into the charger again. The dosemeter head accommodates an AFPC filter on which the radon daughter products deposit. The energy of the alpha particles is reduced by an air layer and a Makrofol decelerating foil. The particles hitting the detector give rise to defects with an intensity proportional to the total linear stopping power at the moment of incidence; ideal tracks 10 μm in size require incident energy of 1.1 to 1.3 MeV. The detector is replaced in a month and worked up in an etching vessel, making use of the higher solubility of the detecting layer of the foil in NaOH at the spot of the alpha particle incidence. (P.A.). 4 figs., 17 refs

  8. HOW DO HOSPITAL STERILISATION PROCEDURES AFFECT THE RESPONSE OF PERSONAL EXTREMITY RINGS AND OF EYE LENS TL DOSEMETERS?

    Science.gov (United States)

    Kopeć, Renata; Bubak, Anna; Budzanowski, Maciej; Sas-Bieniarz, Anna; Szumska, Agnieszka

    2016-09-01

    Stringent standards of hygiene must be applied in medical institutions, especially at operating blocks or during interventional radiology procedures. Medical equipment, including personal dosemeters that have to be worn by medical staff during such procedures, needs therefore to be sterilised. In this study, the effect of various sterilisation procedures has been tested on the dose response of extremity rings and of eye lens dosemeters in which thermoluminescent (TL) detectors (of types MTS-N and MCP-N, respectively) are used. The effects of medical sterilisation procedures were studied: by chemicals, by steam or by ultraviolet (UV), on the dose assessment by extremity rings and by eye lens dosemeters. Since it often happens that a dosemeter is accidentally machine-washed together with protective clothing, the effect of laundering on dose assessment by these dosemeters was also tested. The sterilisation by chemicals is mostly safe for TL detectors assuming that the dosemeters are waterproofed. Following sterilisation by water vapour, the response of these dosemeters diminished by some 30 %, irrespectively of the period of sterilisation; therefore, this method is not recommended. UV sterilisation can be applied to EYE-D™ eye lens dosemeters if their encapsulation is in black. The accidental dosemeter laundry in a washing machine has no impact on measured dose. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Micro-dosemeter instrument (MIDN) for assessing risk in space

    International Nuclear Information System (INIS)

    Pisacane, V. L.; Dolecek, Q. E.; Malak, H.; Cucinotta, F. A.; Zaider, M.; Rosenfeld, A. B.; Rusek, A.; Sivertz, M.; Dicello, J. F.

    2011-01-01

    Radiation in space generally produces higher dose rates than that on the Earth's surface, and contributions from primary galactic and solar events increase with altitude within the magnetosphere. Presently, no personnel monitor is available to astronauts for real-time monitoring of dose, radiation quality and regulatory risk. This group is developing a prototypic instrument for use in an unknown, time-varying radiation field. This micro-dosemeter-dosemeter nucleon instrument is for use in a space-suit, spacecraft, remote rover and other applications. It provides absorbed dose, dose rate and dose equivalent in real time so that action can be taken to reduce exposure. Such a system has applications in health physics, anti-terrorism and radiation-hardening of electronics as well. The space system is described and results of ground-based studies are presented and compared with predictions of transport codes. An early prototype in 2007 was successfully launched, the only solid-state micro-dosemeter to have flown in space. Published by Oxford Univ. Press on behalf of the US Government 2011. (authors)

  10. Operational trials of single- and multi-element CR-39 dosemeters for the DIDO and PLUTO reactors at the Harwell Laboratory

    International Nuclear Information System (INIS)

    Gallacher, G.G.; Perks, C.A.

    1993-01-01

    Single- and multi-element CR-39 dosemeters, developed at the Harwell Laboratory, and a commercially available multi-element CR-39 dosemeter (obtained from Track Analysis Systems Ltd), were evaluated for their potential as neutron dosemeters for personnel working at Harwell Laboratory's research reactors. Owing to the angular dependence of the CR-39 (processed using electrochemical etching), the single-element dosemeter was found to be impractical. Consequently, a multi-element dosemeter was developed, which consisted of a cube of side 36 mm with CR-39 elements (also processed using electrochemical etching) attached to each of the sides. Although this dosemeter was technically suitable for this type of dosimetry, it was considered to be unacceptably bulky in personnel trials. The commercially available CR-39 dosemeter tested was much smaller (the CR-39 was only chemically etched) and this was considered to be acceptable as a personnel dosemeter. In addition, trials with personnel working at active handling glove boxes indicated that single-element dosemeters might be adequate, but further work would be needed to verify this. (author)

  11. Characteristic of the dosemeter used by the service of film dosimetry in the CPHR

    International Nuclear Information System (INIS)

    Capote Ferrera, E.A.; Diaz Bernal, E.; Manzano de Armas, J.F.

    1998-01-01

    Characteristic of the dosemeter used by the service of dosimetria filmica of the CPHR.The use of film dosemeter brings I get the aquisition first it gives data that it includes its evaluation regarding the calibration magnitude and second the interpretation of these data in terms of the magnitude of personal dose, such as the equivalent dose (ICRU 47) or to the effective dose (ICRP 60). presently work the results of the study of the characteristics of the dosemeters are picked up

  12. Energy dependence of pMOS dosemeters

    International Nuclear Information System (INIS)

    Savic, Z.; Stankovic, S.; Kovacevic, M.; Petrovic, M.

    1996-01-01

    The results are presented of experimental work and numerical simulations of the energy response for pMOS dosimetric transistors in their custom packages. Specially produced radiation soft pMOS transistors were used in this experimental work. The irradiation of pMOS dosemeters was done using 60 Co and 137 Cs sources, a dosimetric X ray unit, and a radiotherapeutic linear accelerator in the range of photon energies from 21 keV to 8 MeV. The results show that package geometry and materials can significantly affect and smooth the energy dependence of pMOS transistors and that in custom transistor packages they are not tissue-equivalent dosemeters. Their response in the photon energy range of 45 to 250 keV is significantly larger than it should be (maximum dose enhancement factor can be as high as 8) and some energy compensation techniques must be used in order to fulfill the requirements of corresponding standards. (Author)

  13. Energy dependence of pMOS dosemeters

    Energy Technology Data Exchange (ETDEWEB)

    Savic, Z. [Military Technical Institute, Belgrade (Yugoslavia); Stankovic, S.; Kovacevic, M.; Petrovic, M. [Institute of Nuclear Sciences, Belgrade (Yugoslavia). Radiation Protection Dept.

    1996-10-01

    The results are presented of experimental work and numerical simulations of the energy response for pMOS dosimetric transistors in their custom packages. Specially produced radiation soft pMOS transistors were used in this experimental work. The irradiation of pMOS dosemeters was done using {sup 60}Co and {sup 137}Cs sources, a dosimetric X ray unit, and a radiotherapeutic linear accelerator in the range of photon energies from 21 keV to 8 MeV. The results show that package geometry and materials can significantly affect and smooth the energy dependence of pMOS transistors and that in custom transistor packages they are not tissue-equivalent dosemeters. Their response in the photon energy range of 45 to 250 keV is significantly larger than it should be (maximum dose enhancement factor can be as high as 8) and some energy compensation techniques must be used in order to fulfill the requirements of corresponding standards. (Author).

  14. Hsp90 depletion goes wild

    OpenAIRE

    Siegal, Mark L; Masel, Joanna

    2012-01-01

    Abstract Hsp90 reveals phenotypic variation in the laboratory, but is Hsp90 depletion important in the wild? Recent work from Chen and Wagner in BMC Evolutionary Biology has discovered a naturally occurring Drosophila allele that downregulates Hsp90, creating sensitivity to cryptic genetic variation. Laboratory studies suggest that the exact magnitude of Hsp90 downregulation is important. Extreme Hsp90 depletion might reactivate transposable elements and/or induce aneuploidy, in addition to r...

  15. Calibration of personal dosemeters in terms of the ICRU operational quantities

    International Nuclear Information System (INIS)

    McDonald, J.C.; Hertel, N.E.

    1992-05-01

    The International Commission on Radiological Units and Measurements (ICRU) has defined several new operational quantities for radiation protection purposes. The quantities to be used for personal monitoring are defined at depths in the human body. Because these quantities are impossible to measure directly, the ICRU has recommended that personal dosemeters should be calibrated under simplified conditions on an appropriate phantom, such as the ICRU sphere. The US personal dosimetry accreditation programs make use of a 30 x 30 x 15 cm polymethymethacrylate (PMMA) phantom, therefore it is necessary to relate the response of dosemeters calibrated on this phantom to the ICRU operational quantities. Calculations of the conversion factors to compute dosemeter response in terms of the operational quantities have been performed using the code MCNP. These calculations have also been compared to experimental measurements using thermoluminescent (TLD) detectors

  16. Hsp70 cochaperones HspBP1 and BAG-1M differentially regulate steroid hormone receptor function.

    Directory of Open Access Journals (Sweden)

    Regina T Knapp

    Full Text Available Hsp70 binding protein 1 (HspBP1 and Bcl2-associated athanogene 1 (BAG-1, the functional orthologous nucleotide exchange factors of the heat shock protein 70 kilodalton (Hsc70/Hsp70 chaperones, catalyze the release of ADP from Hsp70 while inducing different conformational changes of the ATPase domain of Hsp70. An appropriate exchange rate of ADP/ATP is crucial for chaperone-dependent protein folding processes. Among Hsp70 client proteins are steroid receptors such as the glucocorticoid receptor (GR, the mineralocorticoid receptor (MR, and the androgen receptor (AR. BAG-1 diversely affects steroid receptor activity, while to date the influence of HspBP1 on steroid receptor function is mostly unknown. Here, we compared the influence of HspBP1 and BAG-1M on Hsp70-mediated steroid receptor folding complexes and steroid receptor activity. Coimmunoprecipitation studies indicated preferential binding of Hsp40 and the steroid receptors to BAG-1M as compared to HspBP1. Furthermore, Hsp70 binding to the ligand-binding domain of GR was reduced in the presence of HspBP1 but not in the presence of BAG-1M as shown by pull-down assays. Reporter gene experiments revealed an inhibitory effect on GR, MR, and AR at a wide range of HspBP1 protein levels and at hormone concentrations at or approaching saturation. BAG-1M exhibited a transition from stimulatory effects at low BAG-1M levels to inhibitory effects at higher BAG-1M levels. Overall, BAG-1M and HspBP1 had differential impacts on the dynamic composition of steroid receptor folding complexes and on receptor function with important implications for steroid receptor physiology.

  17. Hsp10, Hsp70, and Hsp90 immunohistochemical levels change in ulcerative colitis after therapy

    Directory of Open Access Journals (Sweden)

    G. Tomasello

    2011-10-01

    Full Text Available Ulcerative colitis (UC is a form of inflammatory bowel disease (IBD characterized by damage of large bowel mucosa and frequent extra-intestinal autoimmune comorbidities. The role played in IBD pathogenesis by molecular chaperones known to interact with components of the immune system involved in inflammation is unclear. We previously demonstrated that mucosal Hsp60 decreases in UC patients treated with conventional therapies (mesalazine, probiotics, suggesting that this chaperonin could be a reliable biomarker useful for monitoring response to treatment, and that it might play a role in pathogenesis. In the present work we investigated three other heat shock protein/molecular chaperones: Hsp10, Hsp70, and Hsp90. We found that the levels of these proteins are increased in UC patients at the time of diagnosis and decrease after therapy, supporting the notion that these proteins deserve attention in the study of the mechanisms that promote the development and maintenance of IBD, and as biomarkers of this disease (e.g., to monitor response to treatment at the histological level.

  18. Verification of Ca F2:Mn type of dosemeters for personal dosimetry purposes

    International Nuclear Information System (INIS)

    Misovic, M.; Boskovic, Z.; Spasic-Jokic, V.

    1995-01-01

    Verification results of CaF2:Mn type of dosemeters for personal dosimetry purposes are presented in this paper. Tree types of irradiations are proceeded due to verification of relevant features of TLD. It is concluded that mentioned type of dosemeter can be used for purpose of personal dosimetry. (author)

  19. Feasibility study of extremity dosemeter based on polyallyl-diglycol-carbonate (CR-39) for neutron exposure

    International Nuclear Information System (INIS)

    Chau, Q.; Bruguier, P.

    2007-01-01

    In nuclear facilities, some activities such as reprocessing, recycling and production of bare fuel rods expose the workers to mixed neutron-photon fields. For several workplaces, particularly in glove boxes, some workers expose their hands to mixed fields. The mastery of the photon extremity dosimetry is relatively good, whereas the neutron dosimetry still raises difficulties. In this context, the Inst. for Radiological Protection and Nuclear Safety (IRSN) has proposed a study on a passive neutron extremity dosemeter based on chemically etched CR-39 (PADC: polyallyl-diglycol-carbonate), named PN-3, already used in routine practice for whole body dosimetry. This dosemeter is a chip of plastic sensitive to recoil protons. The chemical etching process amplifies the size of the impact. The reading system for tracks counting is composed of a microscope, a video camera and an image analyser. This system is combined with the dose evaluation algorithm. The performance of the dosemeter PN-3 has been largely studied and proved by several laboratories in terms of passive individual neutron dosemeter which is used in routine production by different companies. This study focuses on the sensitivity of the extremity dosemeter, as well as its performance in the function of the level of the neutron energy. The dosemeter was exposed to monoenergetic neutron fields in laboratory conditions and to mixed fields in glove boxes at workplaces. (authors)

  20. The expression of HSP60 and HSP10 in large bowel carcinomas with lymph node metastase

    International Nuclear Information System (INIS)

    Cappello, Francesco; David, Sabrina; Rappa, Francesca; Bucchieri, Fabio; Marasà, Lorenzo; Bartolotta, Tommaso E; Farina, Felicia; Zummo, Giovanni

    2005-01-01

    The involvement of Heat Shock Proteins (HSP) in cancer development and progression is a widely debated topic. The objective of the present study was to evaluate the presence and expression of HSP60 and HSP10 in a series of large bowel carcinomas and locoregional lymph nodes with and without metastases. 82 Astler and Coller's stage C2 colorectal cancers, of which 48 well-differentiated and 34 poorly-differentiated, were selected along with 661 lymph nodes, including 372 with metastases and 289 with reactive hyperplasia only, from the same tumours. Primitive tumours and both metastatic and reactive lymph nodes were studied; specifically, three different compartments of the lymph nodes, secondary follicle, paracortex and medullary sinus, were also analysed. An immunohistochemical research for HSP60 and HSP10 was performed and the semiquantitative results were analysed by statistical analysis to determine the correlation between HSPs expression and 1) tumour grading; 2) degree of inflammation; 3) number of lymph nodes involved; 4) lymph node compartment hyperplasia. Moreover, western blotting was performed on a smaller group of samples to confirm the immunohistochemical results. Our data show that the expression of HSP60, in both primary tumour and lymph node metastasis, is correlated with the tumoral grade, while the HSP10 expression is not. Nevertheless, the levels of HSP10 are commonly higher than the levels of HSP60. In addition, statistical analyses do not show any correlation between the degree of inflammation and the immunopositivity for both HSP60 and HSP10. Moreover, we find a significant correlation between the presence of lymph node metastases and the positivity for both HSP60 and HSP10. In particular, metastatic lymph nodes show a higher percentage of cells positive for both HSP60 and HSP10 in the secondary follicles, and for HSP10 in the medullary sinuses, when compared with hyperplastic lymph nodes. HSP60 and HSP10 may have diagnostic and prognostic

  1. Eurados trial performance test for personal dosemeters for external beta radiation

    DEFF Research Database (Denmark)

    Christensen, P.; Bordy, J.M.; Ambrosi, P.

    2001-01-01

    On the initiative of the European Dosimetry Group (EURADOS) action group 'Harmonisation and Dosimetric Quality Assurance in Individual Monitoring for External Radiation' a trial performance test for whole-body and extremity personal dosemeters broadly representative of those in use in the EU...... the results obtained from the exercise. In particular, based on the replies to a questionnaire issued to each participant, the results are analysed in relation to important design characteristics of the dosemeters taking part in the test....

  2. TL response of LiF: Mg, Cu, P dosemeters in function of the photon energy

    International Nuclear Information System (INIS)

    Gonzalez, P.R.; Azorin, J.; Furetta, C.

    2005-01-01

    In this work the obtained results of studying the response of dosemeters of LiF: Mg, Cu, P + Ptfe, developed in the ININ, commercial dosemeters GR200A (LiF: Mg, Cu, P) of chinese manufacture and TLD-100 (LiF: Mg, Ti) US are presented, when irradiating them with X rays 16, 24, 34.5, 42, 100 and 145 keV of effective energy, with gamma rays of 662 keV ( 137 Cs) and 1252 keV ( 60 Co). The results are presented in function of the sensitivity that the dosemeters showed normalized to gamma radiation of 60 Co. It was appreciated that the dosemeters more equivalent to the tissue, they were those of LiF: Mg, Cu, P + Ptfe, while the less equivalent ones were the TLD-100. (Author)

  3. Hsp90 depletion goes wild

    Directory of Open Access Journals (Sweden)

    Siegal Mark L

    2012-02-01

    Full Text Available Abstract Hsp90 reveals phenotypic variation in the laboratory, but is Hsp90 depletion important in the wild? Recent work from Chen and Wagner in BMC Evolutionary Biology has discovered a naturally occurring Drosophila allele that downregulates Hsp90, creating sensitivity to cryptic genetic variation. Laboratory studies suggest that the exact magnitude of Hsp90 downregulation is important. Extreme Hsp90 depletion might reactivate transposable elements and/or induce aneuploidy, in addition to revealing cryptic genetic variation. See research article http://wwww.biomedcentral.com/1471-2148/12/25

  4. CaSO4: Dy + Teflon thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Campos, L.L.

    1986-01-01

    A pellet dosemeter of CaSO 4 : Dy + Teflon was developed at IPEN. CaSO 4 : Dy thermoluminescent phosphor, grown in the Dosimetric Materials Production Laboratory was chosen, due to its high sensitivity, ease of preparation and comparatively low cost. Pellets were produced by cold pressing and sintering a mixture of CaSO 4 : Dy and Teflon powders. Extensive work was done to study in detail all CaSO 4 : Dy pellets characteristics from the point of view of dosimetry with the purpose of introducing it in the routine use. A filter combination providing an energy independent response from 20 KeV to 1,25 MeV was obtained. The dosemeter consists of three pellets sealed between two thin plastic sheets and placed under plastic and lead filters. The combination of these tree filters allows the exposure as well as the energy determination of an unknown source. (Author) [pt

  5. Fourth intercomparison of personal dosemeters used in US Department of Energy accelerator facilities

    CERN Document Server

    Stewart, R D; Otto, T; Loesch, R M

    2000-01-01

    Personal neutron dosemeters from seven US Department of Energy (DOE) laboratories were mailed to the European Laboratory for Particle Physics (CERN) and irradiated using the well-characterised CERN reference radiation facility (CERF). Neutron dose equivalents determined using the DOE personal dosemeters have been compared to the reference dose equivalent as determined using a tissue-equivalent proportional counter (TEPC). In the 0.5 to 5 mSv dose equivalent range, the comparison of results suggests that the neutron personal dosemeters in use at DOE facilities are capable of estimating dose equivalents for high energy neutrons to within a factor of at least 2 or 3. If a field-specific calibration factor is used to correct the dose equivalent responses, the agreement with the reference dose equivalent for these dosemeters can be improved to better than about 25 to 65at is decoupled from the core in /sup 183,185/Au, becomes the 3/2[532] state (h9/2 parentage) strongly coupled in the doubly-odd /sup 184/Au nucleu...

  6. Altered Cross-linking of HSP27 by Zerumbone as a Novel Strategy for Overcoming HSP27- mediated Resistance

    International Nuclear Information System (INIS)

    Choi, Seo Hyun; Lee, Yoon Jin; Lee, Hae June; Lee, Yun Sil; Kim, Joon; Seo, Woo Duck; Nam, Joo Won; Lee, Yoo Jin; Seo, Eun Kyung

    2010-01-01

    HSPs have diverse roles in the regulation of signal transduction and in numerous aspects of cell growth and death. Indeed, HSP90, HSP70, and HSP27 have each been implicated in promoting cancer. Most HSP27 exists as large oligomeric complexes ranging from 100- 800 kDa, which are probably stabilized by complex interactions between dimeric building blocks. The functional properties of HSP27 are dependent on the quaternary structure of the protein. For example, HSP27 acts as a chaperone and binds to cytochrome c or Daxx as a dimer. Therefore, the oligomerization pattern of HPS27 is believed to have HSP27-mediated protective functions. In this study, zerumbone (ZER), the cytotoxic component isolated from Zingiber zerumbet Smith, induced cross-linking of HSP27 protein by its insertion between the disulfide bond of HSP27, and ZERmediated altered cross-linking of HSP27 modified normal HSP27 dimerization, which resulted in a sensitizing effect to tumors after treatment with radiation. Therefore, altered cross-linking by ZER may be a novel strategy for inhibition of HSP27-mediated resistance

  7. The development of a personal dosemeter for use by aircraft crew

    International Nuclear Information System (INIS)

    Stokes, R.P.; Talbot, L.

    2000-01-01

    This paper describes preliminary work to develop a cosmic-radiation dosemeter for use by military aircraft crew. The dosemeter is based on a combination of CR-39 etched-track detectors and TLD-700 thermoluminescent detectors. It is intended that the CR-39 be used to assess the neutron dose, while the TLD-700 is used to assess the photon and charged particle dose. The sensitivity of CR-39 to the neutron component of cosmic radiation was estimated by irradiating samples of the plastic at the CERN-CEC High Energy Reference Field Facility. This facility produced a radiation field with a neutron spectrum resembling that of the neutron component of cosmic radiation a typical airflight altitudes. The response of the CR-39 was linear over the range of doses studied (0.2-6.0 mSv) and there was no significant fading in the six-month period after irradiation. The TLD-700 component of the dosemeter was calibrated using 137 Cs gamma rays. The response of the TLD-700 was linear over the range of doses studied (0-1.1 mSv) with no significant fade in the six-month period after irradiation. It was concluded that a combination of CR-39 and TLD-700 detectors would provide an effective cosmic-radiation dosemeter for use by military aircraft crew. (author)

  8. An RNA aptamer specific to Hsp70-ATP conformation inhibits its ATPase activity independent of Hsp40.

    Science.gov (United States)

    Thirunavukarasu, Deepak; Shi, Hua

    2015-04-01

    The highly conserved and ubiquitous molecular chaperone heat shock protein 70 (Hsp70) plays a critical role in protein homeostasis (proteostasis). Controlled by its ATPase activity, Hsp70 cycles between two conformations, Hsp70-ATP and Hsp70-ADP, to bind and release its substrate. Chemical tools with distinct modes of action, especially those capable of modulating the ATPase activity of Hsp70, are being actively sought after in the mechanistic dissection of this system. Here, we report a conformation-specific RNA aptamer that binds only to Hsp70-ATP but not to Hsp70-ADP. We have refined this aptamer and demonstrated its inhibitory effect on Hsp70's ATPase activity. We have also shown that this inhibitory effect on Hsp70 is independent of its interaction with the Hsp40 co-chaperone. As Hsp70 is increasingly being recognized as a drug target in a number of age related diseases such as neurodegenerative, protein misfolding diseases and cancer, this aptamer is potentially useful in therapeutic applications. Moreover, this work also demonstrates the feasibility of using aptamers to target ATPase activity as a general therapeutic strategy.

  9. Calibration procedures for mammography dosemeters in Poland

    International Nuclear Information System (INIS)

    Gwiazdowska, B.; Ulkowski, P.; Tolwinski, J.; Bulski, W.

    2002-01-01

    Breast cancer is the most frequent tumour in women and the effectiveness of the treatment depends dramatically on the early detection of the disease. That is the reason why in Poland the mammography control examinations are strongly supported by the Centre of Oncology. In Poland there are over 400 mammography units which account for about 300,000 examinations per year. An investigation performed by the Medical Physics Department of the Centre of Oncology in Warsaw at about 100 mammography facilities proved that in most cases the doses absorbed by the patients could be reduced without decrease of image quality. This is one of the reasons why the Polish Secondary Standard Dosimetry Laboratory (SSDL) dealing mainly with calibration of radiotherapy dosemeters is extending its activities and therefore new facilities and equipment adapted for calibration of mammographic dosemeters have been installed. The mammography dosimetry calibration equipment is permanently installed in the same laboratory room where the radiotherapy dosemeters are calibrated. A base of a mammography unit no longer in clinical use, together with its movable system has been adapted to handle ionization chamber holders. An X-ray tube with a 50 kV high frequency generator was also installed. The tube, a Varian type OEG-50-2, (designed for laboratory applications) with molybdenum anode of an anode angle 23,7 deg. and with a large focus, effective size approximately 5 mm 2 , has an inherent filtration of 0,25 mm beryllium. It is installed in a housing with 2mm lead shielding; a cone shaped beam is formed by a system of three collimators

  10. Basic requirements of dosemeter systems for individual monitoring of external radiation

    International Nuclear Information System (INIS)

    Boehm, J.; Ambrosi, P.

    1985-01-01

    A plea is made for detailed detector independent requirements for dosemeter systems for individual monitoring of external radiation. These requirements should have their origin in the fundamental aspects and concepts of radiation protection for workers, and should be something like a translation of the general principles of individual monitoring into a language easily understandable by producers and users. This work comprises a summary of the general objectives of individual monitoring and discussion of some relevant requirements for dosemeter systems. (orig.) [de

  11. Conformational Activation of Argonaute by Distinct yet Coordinated Actions of the Hsp70 and Hsp90 Chaperone Systems.

    Science.gov (United States)

    Tsuboyama, Kotaro; Tadakuma, Hisashi; Tomari, Yukihide

    2018-05-17

    Loading of small RNAs into Argonaute, the core protein in RNA silencing, requires the Hsp70/Hsp90 chaperone machinery. This machinery also activates many other clients, including steroid hormone receptors and kinases, but how their structures change during chaperone-dependent activation remains unclear. Here, we utilized single-molecule Förster resonance energy transfer (smFRET) to probe the conformational changes of Drosophila Ago2 mediated by the chaperone machinery. We found that empty Ago2 exists in various closed conformations. The Hsp70 system (Hsp40 and Hsp70) and the Hsp90 system (Hop, Hsp90, and p23) together render Ago2 into an open, active form. The Hsp70 system, but not the Hsp90 system alone, is sufficient for Ago2 to partially populate the open form. Instead, the Hsp90 system is required to extend the dwell time of Ago2 in the open state, which must be transiently primed by the Hsp70 system. Our data uncover distinct and coordinated actions of the chaperone machinery, where the Hsp70 system expands the structural ensembles of Ago2 and the Hsp90 system captures and stabilizes the active form. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. The role of phantom parameters on the response of the AEOI Neutriran Albedo Neutron Personnel Dosemeter

    International Nuclear Information System (INIS)

    Sohrabi, M.; Katouzi, M.

    1992-01-01

    The response of the AEOI Neutriran Albedo Neutron Personnel Dosemeter (NANPD) which can also be used for other albedo dosemeter types was determined on 18 different phantom configurations. The effects of type, geometry, material, thickness, dosemeter-to-phantom angle in particular with the presence of legs were investigated using a Pu-Be neutron source. It was concluded that the slab phantoms (single or double) and circular and elliptical cylinder phantoms seemed to provide a better response, whereas the ICRU sphere geometry does not seem to be appropriate for the calibration of albedo dosemeters. It is interesting to note that the presence of legs maintains the constancy of the response in a situation when a radiation worker bends down during work. (author)

  13. Energy dependence of ulrathin LiF-dosemeters for high energy electrons and high energy X-radiation

    International Nuclear Information System (INIS)

    Kupfer, T.

    1977-02-01

    The energy dependence of ultrathin LiF-dosemeters for high energy electrons (5-40 MeV) and high energy X-radiation (6 MV, 42 MV) is experimentally determined. The experimental values are compared to values calculted earlier by other authors. The influence of the thickness of the dosemeters have been considered by comparison of experimental values for 0.03 mm thick dosemeters and theoretical values for 0.13 mm and 0.38 mm thick ones. Also different commersially available dosemeters have been compared by experiments. It is difficult to draw any other conclutions about the energy dependence than that the variation of the relative responce is within +- 3 percent (2S). However the results seems to be sulficient for clinical applications

  14. The use of active personal dosemeters as a personal monitoring device: Comparison with TL dosimetry

    International Nuclear Information System (INIS)

    Boziari, A.; Koukorava, C.; Carinou, E.; Hourdakis, C. J.; Kamenopoulou, V.

    2011-01-01

    The use of active personal dosemeters (APDs) not only as a warning device but also, in some cases, as an official and hence stand-alone dosemeter is rapidly increasing. A comparison in terms of dose, energy and angle dependence, among different types of APD and a routinely used whole-body thermoluminescence dosemeter (TLD) has been performed. Significant differences were found between the TLD readings and mainly some not commonly used APDs. The importance of choosing the best adapted APD according to the radiation field characteristics is pointed out. (authors)

  15. Mesothelioma Cells Escape Heat Stress by Upregulating Hsp40/Hsp70 Expression via Mitogen-Activated Protein Kinases

    Directory of Open Access Journals (Sweden)

    Michael Roth

    2009-01-01

    Full Text Available Therapy with hyperthermal chemotherapy in pleural diffuse malignant mesothelioma had limited benefits for patients. Here we investigated the effect of heat stress on heat shock proteins (HSP, which rescue tumour cells from apoptosis. In human mesothelioma and mesothelial cells heat stress (39–42°C induced the phosphorylation of two mitogen activated kinases (MAPK Erk1/2 and p38, and increased Hsp40, and Hsp70 expression. Mesothelioma cells expressed more Hsp40 and were less sensitive to heat stress compared to mesothelial cells. Inhibition of Erk1/2 MAPK by PD98059 or by Erk1 siRNA down-regulated heat stress-induced Hsp40 and Hsp70 expression and reduced mesothelioma cell survival. Inhibition of p38MAPK by SB203580 or siRNA reduced Hsp40, but not Hsp70, expression and also increased mesothelioma cell death. Thus hyperthermia combined with suppression of p38 MAPK or Hsp40 may represent a novel approach to improve mesothelioma therapy.

  16. Targeting Hsp90-Cdc37: A Promising Therapeutic Strategy by Inhibiting Hsp90 Chaperone Function.

    Science.gov (United States)

    Wang, Lei; Li, Li; Gu, Kai; Xu, Xiao-Li; Sun, Yuan; You, Qi-Dong

    2017-01-01

    The Hsp90 chaperone protein regulates the folding, maturation and stability of a wide variety of oncoproteins. In recent years, many Hsp90 inhibitors have entered into the clinical trials while all of them target ATPase showing similar binding capacity and kinds of side-effects so that none have reached to the market. During the regulation progress, numerous protein- protein interactions (PPI) such as Hsp90 and client proteins or cochaperones are involved. With the Hsp90-cochaperones PPI networks being more and more clear, many cancerous proteins have been reported to be tightly correlated to Hsp90-cochaperones PPI. Among them, Hsp90-Cdc37 PPI has been widely reported to associate with numerous protein kinases, making it a novel target for the treatment of cancers. In this paper, we briefly review the strategies and modulators targeting Hsp90-Cdc37 complex including direct and indirect regulation mechanism. Through these discussions we expect to present inspirations for new insights into an alternative way to inhibit Hsp90 chaperone function. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. Intracellular dynamics of the Hsp90 co-chaperone p23 is dictated by Hsp90

    International Nuclear Information System (INIS)

    Picard, Didier

    2006-01-01

    p23 is a component of the Hsp90 molecular chaperone machine. It binds and stabilizes the ATP-bound dimeric form of Hsp90. Since Hsp90 binds protein substrates in the ATP conformation, p23 has been proposed to stabilize Hsp90-substrate complexes. In addition, p23 can also function as a molecular chaperone by itself and even possesses an unrelated enzymatic activity. Whether it fulfills the latter functions in cells while bound to Hsp90 remains unknown and is difficult to extrapolate from cell-free biochemical experiments. Using the 'fluorescence recovery after photobleaching' (FRAP) technology, I have examined the dynamics of human p23, expressed as a fusion protein with the green fluorescent protein (GFP), in living human HeLa cells. GFP-p23 is distributed throughout the cell, and its mobility is identical in the cytoplasm and in the nucleus. When the Hsp90 interaction is disrupted either with the Hsp90 inhibitor geldanamycin or by introduction of point mutations into p23, the mobility of p23 is greatly accelerated. Under these conditions, its intracellular movement may be diffusion-controlled. In contrast, when wild-type p23 is able to bind Hsp90, a more complex FRAP behavior is observed, suggesting that it is quantitatively bound in Hsp90 complexes undergoing a multitude of other interactions

  18. Synergistic role of HSP90α and HSP90β to promote myofibroblast persistence in lung fibrosis.

    Science.gov (United States)

    Bellaye, Pierre-Simon; Shimbori, Chiko; Yanagihara, Toyoshi; Carlson, David A; Hughes, Philip; Upagupta, Chandak; Sato, Seidai; Wheildon, Nolan; Haystead, Timothy; Ask, Kjetil; Kolb, Martin

    2018-02-01

    Idiopathic pulmonary fibrosis (IPF) is a progressive disease of the lung parenchyma, causing significant morbidity through worsening dyspnoea and overall functional decline. IPF is characterised by apoptosis-resistant myofibroblasts, which are a major source for the excessive production of extracellular matrix (ECM) overtaking normal lung tissue. We sought to study the role of heat shock protein (HSP) isoforms HSP90α and HSP90β, whose distinct roles in lung fibrogenesis remain elusive.We determined the level of circulating HSP90α in IPF patients (n=31) and age-matched healthy controls (n=9) by ELISA. The release of HSP90α and HSP90β was evaluated in vitro in primary IPF and control lung fibroblasts and ex vivo after mechanical stretch on fibrotic lung slices from rats receiving adenovector-mediated transforming growth factor-β1.We demonstrate that circulating HSP90α is upregulated in IPF patients in correlation with disease severity. The release of HSP90α is enhanced by the increase in mechanical stress of the fibrotic ECM. This increase in extracellular HSP90α signals through low-density lipoprotein receptor-related protein 1 (LRP1) to promote myofibroblast differentiation and persistence. In parallel, we demonstrate that the intracellular form of HSP90β stabilises LRP1, thus amplifying HSP90α extracellular action.We believe that the specific inhibition of extracellular HSP90α is a promising therapeutic strategy to reduce pro-fibrotic signalling in IPF. Copyright ©ERS 2018.

  19. The Malarial Exported PFA0660w Is an Hsp40 Co-Chaperone of PfHsp70-x.

    Directory of Open Access Journals (Sweden)

    Michael O Daniyan

    Full Text Available Plasmodium falciparum, the human pathogen responsible for the most dangerous malaria infection, survives and develops in mature erythrocytes through the export of proteins needed for remodelling of the host cell. Molecular chaperones of the heat shock protein (Hsp family are prominent members of the exportome, including a number of Hsp40s and a Hsp70. PFA0660w, a type II Hsp40, has been shown to be exported and possibly form a complex with PfHsp70-x in the infected erythrocyte cytosol. However, the chaperone properties of PFA0660w and its interaction with human and parasite Hsp70s are yet to be investigated. Recombinant PFA0660w was found to exist as a monomer in solution, and was able to significantly stimulate the ATPase activity of PfHsp70-x but not that of a second plasmodial Hsp70 (PfHsp70-1 or a human Hsp70 (HSPA1A, indicating a potential specific functional partnership with PfHsp70-x. Protein binding studies in the presence and absence of ATP suggested that the interaction of PFA0660w with PfHsp70-x most likely represented a co-chaperone/chaperone interaction. Also, PFA0660w alone produced a concentration-dependent suppression of rhodanese aggregation, demonstrating its chaperone properties. Overall, we have provided the first biochemical evidence for the possible role of PFA0660w as a chaperone and as co-chaperone of PfHsp70-x. We propose that these chaperones boost the chaperone power of the infected erythrocyte, enabling successful protein trafficking and folding, and thereby making a fundamental contribution to the pathology of malaria.

  20. Development of radiophotometric dosemeters with high sensitivity using plastic scintillators as a light intensifier

    International Nuclear Information System (INIS)

    Mesquita, C.H. de; Hamada, M.M.

    1987-01-01

    Rectangular plates of plastic scintillators are developed and their effect as light converter evaluated, when used as film-holder in conventional photography dosemeters. In this dosemeter, the radiation that not interacts in the photographic film can be detected by light photons generation in the plastic scintillators, sensitizing the film. (C.G.C.) [pt

  1. Personal radiation monitoring with thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Miano, S.C.

    1987-01-01

    The technique of personal dosimetry used by SAPRA (Servico de Assessoria e Protecao Radiologica S/C Ltda., Brazil) is presented. Thermoluminescent monitors and CaSO 4 : Dy are used in pastilles united by teflon. Characteristics of the dosemeters are briefly reported. The system of thermoluminescent measurement, designed and constructed by SAPRA, and the system of personal monitoring are described. (M.A.C.) [pt

  2. Energy and angular dependence of the personal dosemeter in use at ITN-DPRSN

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Joao G. [Departamento de Proteccao Radiologica e Seguranca Nuclear, Instituto Tecnologico e Nuclear, EN 10, 2686-953 Sacavem (Portugal)], E-mail: jgalves@itn.pt; Calado, Ana M.; Cardoso, Joao V.; Santos, Luis M. [Departamento de Proteccao Radiologica e Seguranca Nuclear, Instituto Tecnologico e Nuclear, EN 10, 2686-953 Sacavem (Portugal)

    2008-02-15

    In this paper the characterization of the dosimetry system and of the personal dosemeter in terms of the stability of the reader calibration factors and of the linearity of the response for the 137Cs reference radiation is presented. The energy and angular dependence of the whole body dosemeter are also shown. The energy dependence was determined performing irradiations with the X-ray narrow series beams N30, N40, N60, N80, N100, N120 and with the gamma reference radiations of 137Cs and 60Co [ISO 4037-1, 1996. X and Gamma Reference Radiation for Calibrating Dosemeters and Doserate Meters and for Determining Their Response as a Function of Photon Energy-Part 1: Radiation Characteristics and Production Methods. International Organization for Standardization, Geneva] in terms of Hp(10) incident on the ISO water slab phantom. The angular dependence of the dosemeter was determined for the angles 0 deg., {+-}20 deg., {+-}40 deg. and {+-}60 deg. with normal using the above mentioned radiation fields. All irradiations were performed at the Laboratorio de Metrologia das Radiacoes lonizantes of ITN-DPRSN. The experiments presented in this paper show the thermoluminescence dosimetry (TLD) system is stable and presents a linear behaviour over and extended dose range. The measurements allowed the determination of the energy dependence at normal incidence and of the angular dependence of the dosemeter currently in use. Further studies are being carried out in order to implement correction factors for supralinearity and low energy measurements.

  3. One year of a thermoluminescent dosemeter and dose record keeping service

    International Nuclear Information System (INIS)

    Dennis, J.A.

    1979-01-01

    A brief description is given of the National Radiological Protection Board's (NRPB) thermoluminescent dosemeter. The automated processing of these dosemeters is linked to a computer-based system of dose records. The postal system is currently used by about 10% of the establishments for which the NRPB provides a personnel monitoring service, but it will soon be extended to other establishments. The distributions of individual whole body doses in 1977 are tabulated. The significant advantage of this new system lies in the improvements in accuracy, completeness, and convenience to the employers of record keeping. (U.K.)

  4. Ammonia stress under high environmental ammonia induces Hsp70 and Hsp90 in the mud eel, Monopterus cuchia.

    Science.gov (United States)

    Hangzo, Hnunlalliani; Banerjee, Bodhisattwa; Saha, Shrabani; Saha, Nirmalendu

    2017-02-01

    The obligatory air-breathing mud eel (Monopterus cuchia) is frequently being challenged with high environmental ammonia (HEA) exposure in its natural habitats. The present study investigated the possible induction of heat shock protein 70 and 90 (hsp70, hsc70, hsp90α and hsp90β) genes and more expression of Hsp70 and Hsp90 proteins under ammonia stress in different tissues of the mud eel after exposure to HEA (50 mM NH 4 Cl) for 14 days. HEA resulted in significant accumulation of toxic ammonia in different body tissues and plasma, which was accompanied with the stimulation of oxidative stress in the mud eel as evidenced by more accumulation of malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2 ) during exposure to HEA. Further, hyper-ammonia stress led to significant increase in the levels of mRNA transcripts for inducible hsp70 and hsp90α genes and also their translated proteins in different tissues probably as a consequence of induction of hsp70 and hsp90α genes in the mud eel. However, hyper-ammonia stress was neither associated with any significant alterations in the levels of mRNA transcripts for constitutive hsc70 and hsp90β genes nor their translated proteins in any of the tissues studied. More abundance of Hsp70 and Hsp90α proteins might be one of the strategies adopted by the mud eel to defend itself from the ammonia-induced cellular damages under ammonia stress. Further, this is the first report of ammonia-induced induction of hsp70 and hsp90α genes under hyper-ammonia stress in any freshwater air-breathing teleost.

  5. Altered Cross-Linking of HSP27 by Zerumbone as a Novel Strategy for Overcoming HSP27-Mediated Radioresistance

    International Nuclear Information System (INIS)

    Choi, Seo-Hyun; Lee, Yoon-Jin; Seo, Woo Duck; Lee, Hae-June; Nam, Joo-Won; Lee, Yoo Jin; Kim, Joon; Seo, Eun-Kyoung; Lee, Yun-Sil

    2011-01-01

    Purpose: HSP27 or HSP25 negatively regulates apoptosis pathways after radiation or chemotherapeutic agents. Abrogation of HSP27 function may be a candidate target for overcoming radio- and chemoresistance. Methods and Materials: Zerumbone (ZER), a cytotoxic component isolated from Zingiber zerumbet smith. Clonogenic survival assay and flow cytometry after Annexin V staining were performed to determine in vitro sensitization effects of ZER with ionizing radiation. A nude mouse xenografting system was also applied to detect in vivo radiosensitizing effects of ZER. Results: ZER produced cross-linking of HSP27, which was dependent on inhibition of the monomeric form of HSP27. ZER was directly inserted between the disulfide bond in the HSP27 dimer and modified normal HSP27 dimerization. Pretreatment with ZER before radiation inhibited the binding affinity between HSP27 and apoptotic molecules, such as cytochrome c and PKCδ, and induced sensitization in vitro and in an in vivo xenografted nude mouse system. Structural analogs lacking only the carbonyl group in ZER, such as α-humulene (HUM) and 8-hydroxy-humulen (8-OH-HUM), did not affect normal cross-linking of HSP27 and did not induce radiosensitization. Conclusions: We suggest that altered cross-linking of HSP27 by ZER is a good strategy for abolishing HSP27-mediated resistance.

  6. Imaging of Hsp70-positive tumors with cmHsp70.1 antibody-conjugated gold nanoparticles

    Directory of Open Access Journals (Sweden)

    Gehrmann MK

    2015-09-01

    Full Text Available Mathias K Gehrmann,1 Melanie A Kimm,2 Stefan Stangl,1 Thomas E Schmid,1 Peter B Noël,2 Ernst J Rummeny,2 Gabriele Multhoff11Department of Radiation Oncology, 2Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, Technische Universität München, Munich, GermanyAbstract: Real-time imaging of small tumors is still one of the challenges in cancer diagnosis, prognosis, and monitoring of clinical outcome. Targeting novel biomarkers that are selectively expressed on a large variety of different tumors but not normal cells has the potential to improve the imaging capacity of existing methods such as computed tomography. Herein, we present a novel technique using cmHsp70.1 monoclonal antibody-conjugated spherical gold nanoparticles for quantification of the targeted uptake of gold nanoparticles into membrane Hsp70-positive tumor cells. Upon binding, cmHsp70.1-conjugated gold nanoparticles but not nanoparticles coupled to an isotype-matched IgG1 antibody or empty nanoparticles are rapidly taken up by highly malignant Hsp70 membrane-positive mouse tumor cells. After 24 hours, the cmHsp70.1-conjugated gold nanoparticles are found to be enriched in the perinuclear region. Specificity for membrane Hsp70 was shown by using an Hsp70 knockout tumor cell system. Toxic side effects of the cmHsp70.1-conjugated nanoparticles are not observed at a concentration of 1–10 µg/mL. Experiments are ongoing to evaluate whether cmHsp70.1 antibody-conjugated gold nanoparticles are suitable for the detection of membrane-Hsp70-positive tumors in vivo.Keywords: heat shock protein 70, tumor biomarker, theranostics, multimodal CT, multispectral CT, k-edge

  7. Detection of irradiation-induced, membrane heat shock protein 70 (Hsp70) in mouse tumors using Hsp70 Fab fragment

    International Nuclear Information System (INIS)

    Stangl, Stefan; Themelis, George; Friedrich, Lars; Ntziachristos, Vasilis; Sarantopoulos, Athanasios; Molls, Michael; Skerra, Arne; Multhoff, Gabriele

    2011-01-01

    Background and purpose: The major stress-inducible heat shock protein 70 (Hsp70) is frequently overexpressed in highly aggressive tumors, and elevated intracellular Hsp70 levels mediate protection against apoptosis. Following therapeutic intervention, such as ionizing irradiation, translocation of cytosolic Hsp70 to the plasma membrane is selectively increased in tumor cells and therefore, membrane Hsp70 might serve as a therapy-inducible, tumor-specific target structure. Materials and methods: Based on the IgG1 mouse monoclonal antibody (mAb) cmHsp70.1, we produced the Hsp70-specific recombinant Fab fragment (Hsp70 Fab), as an imaging tool for the detection of membrane Hsp70 positive tumor cells in vitro and in vivo. Results: The binding characteristics of Hsp70 Fab towards mouse colon (CT26) and pancreatic (1048) carcinoma cells at 4 deg. C were comparable to that of cmHsp70.1 mAb, as determined by flow cytometry. Following a temperature shift to 37 deg. C, Hsp70 Fab rapidly translocates into subcellular vesicles of mouse tumor cells. Furthermore, in tumor-bearing mice Cy5.5-conjugated Hsp70 Fab, but not unrelated IN-1 control Fab fragment (IN-1 ctrl Fab), gradually accumulates in CT26 tumors between 12 and 55 h after i.v. injection. Conclusions: In summary, the Hsp70 Fab provides an innovative, low immunogenic tool for imaging of membrane Hsp70 positive tumors, in vivo.

  8. Dosimetric characteristics of a TLD dosemeter with extremities; Caracteristicas dosimetricas de un dosimetro TLD de extremidades

    Energy Technology Data Exchange (ETDEWEB)

    Molina P, D.; Diaz B, E.; Lien V, R. [Centro de Proteccion e Higiene de las Radiaciones, CPHR, Apdo.Postal 6195, Habana 6, CP 10600, Ciudad Habana (Cuba)

    1999-07-01

    It was designed a TLD dosemeter for the monitoring of the extremities. This one consists in a metallic ring with a circular orifice where is arranged a T L detector of LiF: Mg,Ti (Model JR1152C) 5 x 5 x 0.8 mm{sup 3} covered by a polyethylene fine layer. In this work were studied the dosimetric properties of the dosemeter for its application in the dosimetry of extremities for photonic radiation. the results obtained allow conclude that the designed dosemeter can be used for the extremities monitoring. (Author)

  9. Performance testing of personal dosemeters from eleven dosimetry services in Sweden

    International Nuclear Information System (INIS)

    Lund, E.; Kylloenen, J.-E.; Grindborg, J.-E.; Lindborg, L.

    2001-01-01

    The Swedish regulation, SSI FS 98:5, requires that radiological workers of category A use dosemeters from an approved personal dosimetry service. The 11 services operating in Sweden at the moment use five different types of dosemeter. All have been tested for their ability to determine H p (10) and some of them to determine H p (0.07) according to the European Commission report Radiation Protection 73, EUR 14852, of 1994. The five unique systems have been tested regarding the angular and energy dependence of the response of the dosemeters. The test points for the determination of H p (10) are all, except one, within the trumpet curve and for the unique systems it is shown that the uncertainty related to angular response at three different energies is within the required ±40% except for the lowest X ray quality 40 kV. The energy dependence dominates over the directional dependence and the choice of radiation quality for calibration is of great importance for the system performance. (author)

  10. Validation of a MOSFET dosemeter system for determining the absorbed and effective radiation doses in diagnostic radiology.

    Science.gov (United States)

    Manninen, A-L; Kotiaho, A; Nikkinen, J; Nieminen, M T

    2015-04-01

    This study aimed to validate a MOSFET dosemeter system for determining absorbed and effective doses (EDs) in the dose and energy range used in diagnostic radiology. Energy dependence, dose linearity and repeatability of the dosemeter were examined. The absorbed doses (ADs) were compared at anterior-posterior projection and the EDs were determined at posterior-anterior, anterior-posterior and lateral projections of thoracic imaging using an anthropomorphic phantom. The radiation exposures were made using digital radiography systems. This study revealed that the MOSFET system with high sensitivity bias supply set-up is sufficiently accurate for AD and ED determination. The dosemeter is recommended to be calibrated for energies 80 kVp. The entrance skin dose level should be at least 5 mGy to minimise the deviation of the individual dosemeter dose. For ED determination, dosemeters should be implanted perpendicular to the surface of the phantom to prevent the angular dependence error. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Comparative measurements of external radiation exposure using mobile phones, dental ceramic, household salt and conventional personal dosemeters

    International Nuclear Information System (INIS)

    Ekendahl, Daniela; Bulánek, Boris; Judas, Libor

    2015-01-01

    Because retrospective dosimetry utilises commonly occurring materials and objects, it is particularly useful in cases of large-scale radiation accidents or malevolent acts with radioactive materials where casualties are inflicted on the general public and first emergency responders. The aim of this study was to investigate whether retrospective dosemeters can provide dose estimates with comparable accuracy like conventional personal dosemeters. Using an external source of radiation 137 Cs and an anthropomorphic phantom, we simulated serious irradiation of a human body in anterior-posterior and rotational geometries. Retrospective luminescence dosimetry objects, such as mobile phones, dental ceramic and household salt, and conventional personal dosemeters (thermoluminescent and electronic) were fixed to the anthropomorphic phantom. The doses obtained were compared with specific reference values. In most cases, relative deviations between the measured doses and the reference values did not exceed 20%. As the retrospective and conventional dosemeters show no significant differences in laboratory conditions, the retrospective luminescence dosimetry objects represent a very promising tool if handled properly. - Highlights: • A serious external exposure of human body was simulated. • Doses were measured using both retrospective and conventional dosemeters. • Utilised retrospective dosimetry materials were alumina resistors from mobile phones, household salt and dental ceramic. • Doses obtained were compared with reference values. • Both retrospective and conventional dosemeters gave similar results

  12. Dose estimation by simultaneous measurement of the radon/thoron concentration and the equilibrium factors in air using a passive dosemeter

    International Nuclear Information System (INIS)

    Urban, M.

    1984-03-01

    Responsible for an increased radiation exposure is the inhalation of radon and its short lived daughters. A time integrating passive dosemeter was developed to determine the concentrations of the radon isotopes as well as their equilibrium factors. The α energy spectrum inside a dosemeter is measured by means of a nuclear track detector. The concentrations in air and the equilibrium factors are calculated by using a new mathematical dosemeter model. A small pilot study in houses was done to test the dosemeter. (orig.) [de

  13. Individual TL detector characteristics in automated processing of personnel dosemeters: correction factors as extension to identity codes of dosemeter cards

    International Nuclear Information System (INIS)

    Toivonen, Matti.

    1979-07-01

    One, two and three-component dosemeter cards and their associated processing equipment were developed for personnel monitoring. A novel feature of the TLD system is that the individual sensitivity correction factors of TL detectors for β/γ radiation dosimetry and special timing factors for the readout of neutron detectors are stored on dosemeter cards as an extension of the identity codes. These data are utilized in the automatic TL reading process with the aim of cancelling out the influence of the individual detector characteristics on the measuring results. Stimulation of TL is done with hot nitrogen without removing the detectors from their cards and without any metal contact. Changes in detector characteristics are thus improbable. The reading process can be adjusted in a variety of ways. For example, each detector in the same card can be processed with optimal heating and the specific 250 deg C glow peak of neutron radiation can be roughly separated from the main LiF glow peaks. (author)

  14. Performance of a PADC personal neutron dosemeter at simulated and real workplace fields of the nuclear industry

    International Nuclear Information System (INIS)

    Fiechtner, A.; Boschung, M.; Wernli, C.

    2007-01-01

    In the framework of the EVIDOS (Evaluation of Individual Dosimetry in Mixed Neutron and Photon Radiation Fields) project, funded by the EC, measurements with PADC personal neutron dosemeters were carried out at several workplace fields of the nuclear industry and at simulated workplace fields. The measured personal neutron dose equivalents of the PADC personal neutron dosemeter are compared with values that were assessed within the EVIDOS project by other partners. The detection limits for different spectra types are given. In cases were the neutron dose was too low to be measured by the PADC personal neutron dosemeter, the response is estimated by convoluting the responses to monoenergetic neutrons with the dose energy distribution measured within EVIDOS. The advantages and limitations of the PADC personal neutron dosemeter are discussed. (authors)

  15. Improvement of personal dosimetry - Digital pocket dosemeter

    International Nuclear Information System (INIS)

    Radalj, Z.; Cerovac, Z.; Cerovac, H.; Brumen, V.; Prlic, I.

    1996-01-01

    Physical dosimetric surveillance of professional groups working with various radiation sources is a regular procedure in Croatia, established almost 40 years ago. Data available point out that the majority of professionals under surveillance are those employed in medical facilities, most of them working with X-ray sources. Depending on the nature of professional activities, personnel occupationally exposed to radiation sources are obliged to wear either film badge, TLD or film+TLD badge. Unfortunately, due to the line of data processing, all standard dosemeters have the same disadvantage i.e. up to 40 days delay in dose reporting, regarding the time of actual exposure. The significance of such a delay raises in cases when radiation dose was received within the short time or when technical failure on the operating unit(s) is suspected. Bearing this in mind, the additional dosimetric monitoring becomes an imperative. Therefore, we decided to introduce a palette of digital pocket dosemeters, meant to be used in different workplaces in the radiation zone, each of them being adjusted to the specificities of a particular workplace

  16. A neutron dosemeter for nuclear criticality accidents.

    Science.gov (United States)

    d'Errico, F; Curzio, G; Ciolini, R; Del Gratta, A; Nath, R

    2004-01-01

    A neutron dosemeter which offers instant read-out has been developed for nuclear criticality accidents. The system is based on gels containing emulsions of superheated dichlorodifluoromethane droplets, which vaporise into bubbles upon neutron irradiation. The expansion of these bubbles displaces an equivalent volume of gel into a graduated pipette, providing an immediate measure of the dose. Instant read-out is achieved using an array of transmissive optical sensors which consist of coupled LED emitters and phototransistor receivers. When the gel displaced in the pipette crosses the sensing region of the photomicrosensors, it generates a signal collected on a computer through a dedicated acquisition board. The performance of the device was tested during the 2002 International Accident Dosimetry Intercomparison in Valduc, France. The dosemeter was able to follow the initial dose gradient of a simulated accident, providing accurate values of neutron kerma; however, the emulsion was rapidly depleted of all its drops. A model of the depletion effects was developed and it indicates that an adequate dynamic range of the dose response can be achieved by using emulsions of smaller droplets.

  17. A neutron dosemeter for nuclear criticality accidents

    International Nuclear Information System (INIS)

    D'Errico, F.; Curzio, G.; Ciolini, R.; Del Gratta, A.; Nath, R.

    2004-01-01

    A neutron dosemeter which offers instant read-out has been developed for nuclear criticality accidents. The system is based on gels containing emulsions of superheated dichlorodifluoromethane droplets, which vaporise into bubbles upon neutron irradiation. The expansion of these bubbles displaces an equivalent volume of gel into a graduated pipette, providing an immediate measure of the dose. Instant read-out is achieved using an array of transmissive optical sensors which consist of coupled LED emitters and phototransistor receivers. When the gel displaced in the pipette crosses the sensing region of the photo microsensors, it generates a signal collected on a computer through a dedicated acquisition board. The performance of the device was tested during the 2002 International Accident Dosimetry Intercomparison in Valduc (France)). The dosemeter was able to follow the initial dose gradient of a simulated accident, providing accurate values of neutron kerma; however, the emulsion was rapidly depleted of all its drops. A model of the depletion effects was developed and it indicates that an adequate dynamic range of the dose response can be achieved by using emulsions of smaller droplets. (authors)

  18. C-terminal sequences of hsp70 and hsp90 as non-specific anchors for tetratricopeptide repeat (TPR) proteins.

    Science.gov (United States)

    Ramsey, Andrew J; Russell, Lance C; Chinkers, Michael

    2009-10-12

    Steroid-hormone-receptor maturation is a multi-step process that involves several TPR (tetratricopeptide repeat) proteins that bind to the maturation complex via the C-termini of hsp70 (heat-shock protein 70) and hsp90 (heat-shock protein 90). We produced a random T7 peptide library to investigate the roles played by the C-termini of the two heat-shock proteins in the TPR-hsp interactions. Surprisingly, phages with the MEEVD sequence, found at the C-terminus of hsp90, were not recovered from our biopanning experiments. However, two groups of phages were isolated that bound relatively tightly to HsPP5 (Homo sapiens protein phosphatase 5) TPR. Multiple copies of phages with a C-terminal sequence of LFG were isolated. These phages bound specifically to the TPR domain of HsPP5, although mutation studies produced no evidence that they bound to the domain's hsp90-binding groove. However, the most abundant family obtained in the initial screen had an aspartate residue at the C-terminus. Two members of this family with a C-terminal sequence of VD appeared to bind with approximately the same affinity as the hsp90 C-12 control. A second generation pseudo-random phage library produced a large number of phages with an LD C-terminus. These sequences acted as hsp70 analogues and had relatively low affinities for hsp90-specific TPR domains. Unfortunately, we failed to identify residues near hsp90's C-terminus that impart binding specificity to individual hsp90-TPR interactions. The results suggest that the C-terminal sequences of hsp70 and hsp90 act primarily as non-specific anchors for TPR proteins.

  19. Tl response of LiF: Mg, Cu, P + PTFE (Mexico) and GR200A (China) dosemeters

    International Nuclear Information System (INIS)

    Gonzalez M, P.R.; Azorin N, J.; Furetta, C.

    2003-01-01

    TLD-100 was the commercial dosemeter more known since some decades ago. This dosemeter was considered for many research groups as the reference material for developing new Tl materials for ionizing radiation dosimetry. Actually it seems that TLD-100 is going to be replaced by the Chinese material GR200A, as reference material due that this material in addition to be considered as a tissue equivalent material, is 30 to 35 times more sensitive that TLD- 100. Results of the study of the Tl response of LiF: Mg, Cu, P + Ptfe developed at ININ-Mexico, comparing them with those of GR200A are presented. These results showed that the sensitivity (s = Tl intensity/weight x dose) to gamma radiation of the LiF: Mg, Cu, P + Ptfe dosimeters was 4.34 meanwhile that of the commercial dosemeter was 3.41. Detection threshold of the dosemeters studied was 2.22 and 0.52 μGy respectively Repeatability after 10 cycles Irradiation-reading-annealing was ±1.39% and ±1.86% respectively. Both types of dosemeters presented a linear response as a function of gamma radiation in the range from 0.02 mGy and 100 Gy. (Author)

  20. Official dosimetry with individual electronic dosemeters - the concept in Germany

    International Nuclear Information System (INIS)

    Czarwinski, R.; Kaulard, J.; Pfeffer, W.

    2005-01-01

    Full text: Presently, in Germany passive dosemeters (film batches, RPL, TLD) are used for the official individual monitoring of occupational exposed personal. The application of electronic individual dosemeters (EPD) is carried out mainly for the operative radiation protection control particularly in nuclear power engineering companies, big hospitals und research centres. This means in such institutions double monitoring exists - legally and operatively. A crucial advantage of EPD compared to passive dosemeter is the possibility to adapt the monitoring period to the working time in the control area, e.g. a job related monitoring is available. Germany started a project for an optimized implementation of EPD into the official dosimetry. Objective of the project whose results will be described in the paper is the harmonization of radiation protection of companies workers and outside workers concerning the record of individual and job related exposures. The approval of the EPD by the Federal and Laender authorities as an official dosimetric system demands the implementation of special requirements concerning the data acquisition, data transfer and data evaluation. These issues are focuses of the Federal research project, supervised by the Federal Office for Radiation Protection (BfS) and performed by the Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS), Cologne to develop a concept in the first stage. (author)

  1. Development of an improved dosemeter for assessments of risk to the eye

    International Nuclear Information System (INIS)

    Eakins, J.S.; Gilvin, P.J.; Hager, L.G.; Tanner, R.J.

    2014-01-01

    To develop an improved dosemeter to assess photon and beta exposures of the eye lens, and in response to issues surrounding the preferred values of H lens to be used for guiding operational radiation protection, a programme of re-optimization of the current PHE thermoluminescence dosemeter has been performed. In particular, refinements of the filter located in front of the sensitive 7 LiF:Mg,Cu,P element have been considered, so that the dose response characteristics of the device provide a better and more conservative estimate of risk. The investigation was performed using the Monte Carlo modelling software MCNP5, to produce a final design that featured a filter containing a 9.5 mm diameter polypropylene hemisphere truncated to a maximum thickness of 3.0 mm. The responses of this design in photon and electron fields are presented here, contrasted against those of the existing PHE eye dosemeter, with respect to the operational quantity H p (3,E,θ) and both current and suggested values for the absorbed dose per fluence risk profile for the lens of the eye. - Highlights: • A programme of re-optimization of the current PHE eye dosemeter has been performed. • A design featuring a truncated hemispherical filter was found to be optimal. • The shape of the filter better resembles the rotational profile of the eye. • Response characteristics depend on the calibration conditions taken to provide the best risk estimate

  2. The Future of Bio-technology

    Science.gov (United States)

    Trent, Jonathan

    2005-01-01

    Hosts of technologies, most notably in electronics, have been on the path of miniaturization for decades and in 2005 they have crossed the threshold of the nano-scale. Crossing the nano-scale threshold is a milestone in miniaturization, setting impressive new standards for component-packing densities. It also brings technology to a scale at which quantum effects and fault tolerance play significant roles and approaches the feasible physical limit form many conventional "top-down" manufacturing methods. I will suggest that the most formidable manufacturing problems in nanotechnology will be overcome and major breakthroughs will occur in a host of technologies, when nanotechnology converges with bio-technology; i.e. I will argue that the future of bio-technology is in nanotechnology. In 2005, methods in molecular biology, microscopy, bioinformatics, biochemistry, and genetic engineering have focused considerable attention on the nano-scale. On this scale, biology is a kind of recursive chemistry in which molecular recognition, self-assembly, self-organization and self-referencing context-control lead to the emergence of the complexity of structures and processes that are fundamental to all life forms. While we are still far from understanding this complexity, we are on the threshold of being able to use at least some of these biological properties for .technology. I will discuss the use of biomolecules, such as DNA, RNA, and proteins as "tools" for the bio-technologist of the future. More specifically, I will present in some detail an example of how we are using a genetically engineered 60-kDa protein (HSP60) from an organism living in near boiling sulfuric acid to build nano-scale templates for arranging metallic nanoparticles. These "extremophile" HSP60s self-assemble into robust double-ring structures called "chaperonins," which further assemble into filaments and arrays with nanometer accuracy. I will discuss our efforts to use chaperonins to organize quantum

  3. Calibration of thermoluminescence skin dosemeter response to beta emitters found in Ontario Hydro nuclear power stations

    International Nuclear Information System (INIS)

    Walsh, M.L.; Agnew, D.A.; Donnelly, K.E.

    1984-01-01

    The response of the Ontario Hydro Thermoluminescence Dosimetry System to beta radiation in nuclear power station environments was evaluated. Synthetic beta spectra were constructed, based on activity samples from heat transport systems and fuelling machine contamination smears at nuclear power stations. Using these spectra and dosemeter energy response functions, an overall response factor for the skin dosemeter relative to skin dose at 7 mg.cm -2 was calculated. This calculation was done assuming three specific geometries: (1) an infinite uniformly contaminated plane source at a distance of 33 cm (50 mg.cm -2 total shielding) from the receptor; (2) an infinite cloud surrounding the receptor; (3) a point source at 33 cm. Based on these calculations, a conservative response factor of 0.7 has been chosen. This provides an equation for skin dose assignment, i.e. Skin Dose = 1.4 x Skin Dosemeter Reading when the skin dosemeter is directly calibrated in mGy(gamma). (author)

  4. Development of CaSO4:Dy based ring dosemeter for extremity monitoring of radiation workers in India

    International Nuclear Information System (INIS)

    Srivastava, Kshama; Meenal, P.; Bhagat, R.V.; Singh, R.; Kolambe, D.H.; Chougaonkar, M.P.; Sapra, B.K.

    2014-01-01

    Extremity dosemeters are required to be worn in cases where the dose to extremities is expected to be significantly greater than the dose to the whole body. In India, CaSO 4 :Dy based three element personnel monitoring TLD badge worn at chest and wrist level are used for whole body and extremity monitoring, respectively. Presently no official/legal finger dosemeter is available for extremity monitoring for radiation workers in the country. To cater to the long standing requirement of finger dosimeter, a new compact three-element Extremity Ring Badge Dosemeter (ERBD) has been developed for measurement of the equivalent doses received by the extremities of radiation workers in terms of operational quantity Hp(0.07). It was aimed to meet the performance requirement of IEC/ISO standards. This paper gives the design detail and result of experimental studies of ERB dosemeter

  5. Comparative baseline levels of mercury, Hsp 70 and Hsp 60 in subsistence fish from the Yukon-Kuskokwim delta region of Alaska.

    Science.gov (United States)

    Duffy, L K; Scofield, E; Rodgers, T; Patton, M; Bowyer, R T

    1999-10-01

    In subsistence fish; northern pike (Esox lucius), burbot (Lota lota), whitefish (Coregonus nelsoni), grayling (Thymallus arcticus) and sheefish (Stenodus lencichthys), we determined the Hsp 60 and Hsp 70 levels in 31 samples from adult fish gills. A dot-blot analysis using antibodies to either Hsp 70 or Hsp 60 showed the average Hsp 70 concentration was 9.1 microg/mg protein, while the average Hsp 60 concentration was 147.4 microg/mg protein. Mercury levels in muscle tissue in these fish averaged 0.382 ppm. Using a subset of samples (n = 24), we determined that the major component in the muscle of Alaskan subsistence fish was methyl mercury. No correlation was observed between Hsp 60 or Hsp 70 expression in gill tissue and mercury concentrations in muscle tissue. Hsp 60 and Hsp 70 protein levels in the gills were correlated.

  6. Systematic processing of the external individual monitoring data obtained by photographic film and capacitor dosemeters

    International Nuclear Information System (INIS)

    Krueger, F.; Shtuk, D.

    1983-01-01

    Individual radiation load measurements have been carried out both with photographic film and capacitor type dosemeters (CD). Systematic statistics methods were applied for the obtained data processing. The CD data were shown to exceed those measured with the film dosemeters. Specific features of the CD application are revealed that should be taken into account in practice [ru

  7. New generation of ''legal'' dosemeters

    International Nuclear Information System (INIS)

    Fletcher, R.

    1991-01-01

    In the early 1980s research at the National Radiological Protection Board in the UK proved the feasibility of using solid state electronics in an entirely new dosimetry technology - capable of reaching right down into the low energy photon ranges, and able to detect beta radiation. In 1988 the NRPB undertook a joint venture with Siemens Plessey Controls to develop a marketable personal dosemeter meeting full Health and Safety Executive approval as a ''legal'' instrument. The Electronic Personal Dosemeter (EPD) was thus conceived, and will reach the pre-production stage early this year. The EPD makes use of state-of-the-art silicon integrated circuit technology, with a custom amplifier and microprocessor system. The liquid crystal display continuously shows the accumulated short-term penetrating dose in terms of the Hp (10) unit, and can also show superficial dose and dose rates. Because the EPD must be continuously powered, the custom lithium battery was commissioned to ensure a minimum service interval of 12 months. The EPD is the size and weight of a small pocket pager. Although dose data can be read directly from the EPD, a comprehensive data management system is needed to effect real-life use in industry. The EPD thus communicates by infra-red link to a reader unit which interfaces an IBM-compatible PC, allowing authorized personnel to read the dose memories and perform dose alarm threshold settings. (author)

  8. Heat shock protein (Hsp) 40 mutants inhibit Hsp70 in mammalian cells

    NARCIS (Netherlands)

    Michels, AA; Kanon, B; Bensaude, O; Kampinga, HH

    1999-01-01

    Heat shock protein (Hsp) 70 and Hsp40 expressed in mammalian cells had been previously shown to cooperate in accelerating the reactivation of heat-denatured firefly luciferase (Michels, A. A., Kanon, B., Konings, A. W. T., Ohtsuka, K,, Bensaude, O., and Kampinga, H. H. (1997) J. Biol. Chem. 272,

  9. Unbiased metal oxide semiconductor ionising radiation dosemeter

    International Nuclear Information System (INIS)

    Kumurdjian, N.; Sarrabayrouse, G.J.

    1995-01-01

    To assess the application of MOS devices as low dose rate dosemeters, the sensitivity is the major factor although little studies have been performed on that subject. It is studied here, as well as thermal stability and linearity of the response curve. Other advantages are specified such as large measurable dose range, low cost, small size, possibility of integration. (D.L.)

  10. Performance tests of a CaSO4:Dy based thermoluminescence personal dosemeter

    International Nuclear Information System (INIS)

    Azorin, J.; Gutierrez, A.; Niewiadomski, T.

    1986-01-01

    In order to replace LiF commercial thermoluminescence dosemeters (TLDs) now used in personnel monitoring, we developed a TLD personnel monitoring badge based on pellets of CaSO 4 :Dy bound in pure KBr placed in plastic holders provided with 0.8 mm Pb filters to compensate for the energy dependence of CaSO 4 :Dy. Performance tests, based on the proposals of international standards for TLDs intended to be used as general deep tissue personal dosemeters, were done by developing the detailed test methods both for the tests required by the International Atomic Energy Agency (fading, linearity, effect of fluorescent light and sunlight and stability under standard climatic conditions) and to meet the requirements of the International Electrotechnical Commission (batch homogeneity, detection threshold, stability of zero point repeatibility and residual). Initial tests showed a high residual and an increase of inhomogeneity. However, these drawbacks were overcome by changing the annealing procedure and the readout conditions. Using these new conditions TLDs met all the requirements for personal dosemeters. (author)

  11. Cloning of three heat shock protein genes (HSP70, HSP90α and HSP90β) and their expressions in response to thermal stress in loach (Misgurnus anguillicaudatus) fed with different levels of vitamin C.

    Science.gov (United States)

    Yan, Jie; Liang, Xiao; Zhang, Yin; Li, Yang; Cao, Xiaojuan; Gao, Jian

    2017-07-01

    Heat shock protein 70 (HSP70) and 90 (HSP90) are the most broadly studied proteins in HSP families. They play key roles in cells as molecular chaperones, in response to stress conditions such as thermal stress. In this study, full-length cDNA sequences of HSP70, HSP90α and HSP90β from loach Misgurnus anguillicaudatus were cloned. The full-length cDNA of HSP70 in loach was 2332bp encoding 644 amino acids, while HSP90α and HSP90β were 2586bp and 2678bp in length, encoding 729 and 727 amino acids, respectively. The deduced amino acid sequences of HSP70 in loach shared the highest identity with those of Megalobrama amblycephala and Cyprinus carpio. The deduced amino acid sequences of HSP90α and HSP90β in loach both shared the highest identity with those of M. amblycephala. Their mRNA tissue expression results showed that the maximum expressions of HSP70, HSP90α and HSP90β were respectively present in the intestine, brain and kidney of loach. Quantitative real-time PCR was employed to analyze the temporal expressions of HSP70, HSP90α and HSP90β in livers of loaches fed with different levels of vitamin C under thermal stress. Expression levels of the three HSP genes in loach fed the diet without vitamin C supplemented at 0 h of thermal stress were significantly lower than those at 2 h, 6 h, 12 h and 24 h of thermal stress. It indicated that expressions of the three HSP genes were sensitive to thermal stress in loach. The three HSP genes in loaches fed with 1000 mg/kg vitamin C expressed significantly lower than other vitamin C groups at many time points of thermal stress, suggesting 1000 mg/kg dietary vitamin C might decrease the body damages caused by the thermal stress. This study will be of value for further studies into thermal stress tolerance in loach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Deletion in HSP110 T17: correlation with wild-type HSP110 expression and prognostic significance in microsatellite-unstable advanced gastric cancers.

    Science.gov (United States)

    Kim, Kyung-Ju; Lee, Tae Hun; Kim, Jung Ho; Cho, Nam-Yun; Kim, Woo Ho; Kang, Gyeong Hoon

    2017-09-01

    Deletion of the HSP110 T 17 mononucleotide repeat has recently been identified as a prognostic marker that is correlated with wild-type HSP110 (HSP110wt) expression in microsatellite instability-high (MSI-H) colorectal cancers. The aim of this study was to assess the correlation between deletion of the HSP110 T 17 repeat and expression of HSP110wt using DNA testing and immunohistochemistry and to determine the prognostic implications of HSP110 T 17 deletion in MSI-H advanced gastric cancers (GCs). The status of HSP110wt expression was evaluated by immunohistochemistry using an HSP110wt-specific antibody in 142 MSI-H advanced GCs. The size of the HSP110 T 17 repeat deletion was analyzed in 96 MSI-H advanced GCs; deletions were divided into small (0-2base pairs) and large deletions (3-5base pairs). Low and high expressions of HSP110wt were detected in 38 (26.8%) and 104 (73.2%) of the 142 cases, respectively. The HSP110 T 17 deletion was observed in 45 (46.9%) of the 96 MSI-H GC samples. Tumors with high expression of HSP110wt showed a tendency to have small or no deletion of HSP110 T 17 . In Kaplan-Meier survival analysis, tumors with a large HSP110 T 17 deletion were associated with favorable overall survival and disease-free survival compared with those with small/no deletion of HSP110 T 17 . However, HSP110 T 17 deletion size was not an independent prognostic factor in multivariate analysis. In summary, deletion of the HSP110 T 17 repeat was frequently observed in MSI-H GCs, and HSP110 T 17 deletion size was inversely correlated with HSP110wt expression status. Large HSP110 T 17 was not a prognostic indicator in MSI-H GCs. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Jasmonate signalling in Arabidopsis involves SGT1b-HSP70-HSP90 chaperone complexes.

    Science.gov (United States)

    Zhang, Xue-Cheng; Millet, Yves A; Cheng, Zhenyu; Bush, Jenifer; Ausubel, Frederick M

    Plant hormones play pivotal roles in growth, development and stress responses. Although it is essential to our understanding of hormone signalling, how plants maintain a steady state level of hormone receptors is poorly understood. We show that mutation of the Arabidopsis thaliana co-chaperone SGT1b impairs responses to the plant hormones jasmonate, auxin and gibberellic acid, but not brassinolide and abscisic acid, and that SGT1b and its homologue SGT1a are involved in maintaining the steady state levels of the F-box proteins COI1 and TIR1, receptors for jasmonate and auxin, respectively. The association of SGT1b with COI1 is direct and is independent of the Arabidopsis SKP1 protein, ASK1. We further show that COI1 is a client protein of SGT1b-HSP70-HSP90 chaperone complexes and that the complexes function in hormone signalling by stabilizing the COI1 protein. This study extends the SGT1b-HSP90 client protein list and broadens the functional scope of SGT1b-HSP70-HSP90 chaperone complexes.

  14. Measurements of eye lens doses in interventional cardiology using OSL and electronic dosemeters

    International Nuclear Information System (INIS)

    Sanchez, R.M.; Vano, E.; Fernandez, J.M.; Ginjaume, M.; Duch, M.A.

    2014-01-01

    The purpose of this paper is to test the appropriateness of OSL and electronic dosemeters to estimate eye lens doses at interventional cardiology environment. Using TLD as reference detectors, personal dose equivalent was measured in phantoms and during clinical procedures. For phantom measurements, OSL dose values resulted in an average difference of 215 % vs. TLD. Tests carried out with other electronic dosemeters revealed differences up to ±20 % versus TLD. With dosemeters positioned outside the goggles and when TLD doses were >20 μSv, the average difference OSL vs. TLD was 29 %. Eye lens doses of almost 700 μSv per procedure were measured in two cases out of a sample of 33 measurements in individual clinical procedures, thus showing the risk of high exposure to the lenses of the eye when protection rules are not followed. The differences found between OSL and TLD are acceptable for the purpose and range of doses measured in the survey (authors)

  15. Field calibration of a TLD albedo dosemeter in the high-energy neutron field of CERF

    International Nuclear Information System (INIS)

    Haninger, T.; Kleinau, P.; Haninger, S.

    2017-01-01

    The new albedo dosemeter-type AWST-TL-GD 04 has been calibrated in the CERF neutron field (CERN-EU high-energy Reference Field). This type of albedo dosemeter is based on thermoluminescent detectors (TLDs) and used by the individual monitoring service of the Helmholtz Zentrum Muenchen (AWST) since 2015 for monitoring persons, who are exposed occupationally against photon and neutron radiation. The motivation for this experiment was to gain a field specific neutron correction factor N n for workplaces at high-energy particle accelerators. N n is a dimensionless factor relative to a basic detector calibration with 137 Cs and is used to calculate the personal neutron dose in terms of H p (10) from the neutron albedo signal. The results show that the sensitivity of the albedo dosemeter for this specific neutron field is not significantly lower as for fast neutrons of a radionuclide source like 252 Cf. The neutron correction factor varies between 0.73 and 1.16 with a midrange value of 0.94. The albedo dosemeter is therefore appropriate to monitor persons, which are exposed at high-energy particle accelerators. (authors)

  16. Two miniature electronic dosemeters Yperwatch - Gamcard

    International Nuclear Information System (INIS)

    Clavel, B.; Jaillon, J.

    1993-01-01

    Yperwatch and Gamcard were miniature electronic gamma personal dose and dose rate monitors. The Yperwatch is mounted in a wristwatch and the Gamcard in a case of the size of a standard credit card. The technology provides users with all the performance of a standard professional electronic dosemeter (integrated dose, dose rate, audible alarms, time in use). Yperwatch and Gamcard are based on well-proven electronic dosimetry technology, but with a greater ease of use. (author)

  17. Individual monitoring and its quality assurance using thermoluminescent CaSO[sub 4]:Dy Teflon tape dosemeters in India

    Energy Technology Data Exchange (ETDEWEB)

    Nagpal, J.S.; Popli, K.L.; Varadharajan, G.; Kher, R.K.; Venkataraman, G. (Bhabha Atomic Research Centre, Bombay (India). Div. of Radiological Protection)

    1994-01-01

    CaSO[sub 4]:Dy Teflon thermoluminscence dosemeters have been fabricated indigenously in continuous tape form. TL response of the tape dosemeters to [beta] and [gamma] radiations has been studied as a function of the dosemeter thickness to arrive at its optimum value. A single 80 mg.cm[sup -2] thick tape dosemeter (51 mm x 17 mm) along with a mica strip replaces the earlier use of three 200 mg.cm[sup -2] thick disc dosemeters for routine individual monitoring. The tape cards have been in field use for two and half years. The performance characteristics of the cards under laboratory and field conditions are discussed. Dose computation algorithms have been developed to give whole-body dose (mGy) and skin dose (mGy)for photons and [beta] radiation respectively from the TL outputs of three dosimetric elements under 1000 mg.cm[sup -2] Cu + Al composite filter, 180 mg.cm[sup -2] Perspex and an open region in a cardholder. Results of the Quality Assurance Programme, covering various TL monitoring stations in India, are also presented. Based on ANSI criteria, only one outlier was observed over the past seven years. (Author).

  18. Evaluations of absorbed dose ratio factor of Al2O3 dosemeter in radiotherapy photon beams using cavity theory

    International Nuclear Information System (INIS)

    Zhu, J.; Chen, S.; Chen, L.; Liu, X.

    2012-01-01

    The aim of the work was to evaluate the absorbed dose ratio factor f md of an Al 2 O 3 dosemeter to water in photon radiotherapy beams using cavity theory. Burlin theory was used for calculating of this ratio. The effective mass attenuation coefficient β was obtained by comparing Monte Carlo simulations in monoenergetic photon beams. The evaluations of the absorbed dose ratio factor f md were studied for Al 2 O 3 dosemeters of different sizes, which were placed at various depths of the water phantom in different radiation field sizes of Mohan's 6, 10 and 15-MV X-rays. Beyond the build-up region, the variation of f md increases by 0.25 % as the depth increases from 4 to 10 cm. The maximum variation due to different dosemeter sizes is 8.3 %. The difference in the f md due to different radiation field sizes is 1.5 %. The effect of the dosemeter size cannot be neglected. The difference in the f md due to the radiation field sizes of different beams would increase as the dosemeter size increases. (authors)

  19. Genome-wide identification of heat shock proteins (Hsps) and Hsp interactors in rice: Hsp70s as a case study.

    Science.gov (United States)

    Wang, Yongfei; Lin, Shoukai; Song, Qi; Li, Kuan; Tao, Huan; Huang, Jian; Chen, Xinhai; Que, Shufu; He, Huaqin

    2014-05-07

    Heat shock proteins (Hsps) perform a fundamental role in protecting plants against abiotic stresses. Although researchers have made great efforts on the functional analysis of individual family members, Hsps have not been fully characterized in rice (Oryza sativa L.) and little is known about their interactors. In this study, we combined orthology-based approach with expression association data to screen rice Hsps for the expression patterns of which strongly correlated with that of heat responsive probe-sets. Twenty-seven Hsp candidates were identified, including 12 small Hsps, six Hsp70s, three Hsp60s, three Hsp90s, and three clpB/Hsp100s. Then, using a combination of interolog and expression profile-based methods, we inferred 430 interactors of Hsp70s in rice, and validated the interactions by co-localization and function-based methods. Subsequent analysis showed 13 interacting domains and 28 target motifs were over-represented in Hsp70s interactors. Twenty-four GO terms of biological processes and five GO terms of molecular functions were enriched in the positive interactors, whose expression levels were positively associated with Hsp70s. Hsp70s interaction network implied that Hsp70s were involved in macromolecular translocation, carbohydrate metabolism, innate immunity, photosystem II repair and regulation of kinase activities. Twenty-seven Hsps in rice were identified and 430 interactors of Hsp70s were inferred and validated, then the interacting network of Hsp70s was induced and the function of Hsp70s was analyzed. Furthermore, two databases named Rice Heat Shock Proteins (RiceHsps) and Rice Gene Expression Profile (RGEP), and one online tool named Protein-Protein Interaction Predictor (PPIP), were constructed and could be accessed at http://bioinformatics.fafu.edu.cn/.

  20. The former tests realized to a personal neutron dosemeter based on solid nuclear tracks detector

    International Nuclear Information System (INIS)

    Camacho, M.E.; Tavera, L.; Balcazar, M.

    1997-01-01

    Due to the increase in the use of neutron radiation a personal neutron dosemeter based on solid nuclear tracks detector (DSTN) was designed and constructed. The personal dosemeter design consists of three arrangements. The first one consists of a plastic nuclear tracks detector (LR115 or CR39) in contact with a LiF pellet. The second one is the same that above but it placed among two cadmium pellets and, the third one is formed by the alone detector without converter neither neutron absorber. The three arrangements are placed inside a plastic porta detector hermetically closed to avoid the bottom produced by environmental radon whichever both detectors (LR115 and CR39) are sensitive. In this work the former tests realized to that dosemeter are presented. (Author)

  1. Use of digital dosemeters for supporting staff radiation safety in paediatric interventional radiology suites

    International Nuclear Information System (INIS)

    McNeil, S. M.; Lai, P.; Connolly, B. L.; Gordon, C. L.

    2013-01-01

    Modern-day interventional radiology (IR) procedures impart a wide range of occupational radiation doses to team members. Unlike thermoluminescent badges, digital dosemeters provide real-time dose readings, making them ideal for identifying different components during IR procedures, which influence staff radiation safety. This study focused solely on paediatric IR (PIR) cases. Digital dosemeters measured the impact of imaging modality, shielding, patient and operator specific factors, on the radiation dose received during various simulated and real live PIR procedures. They recorded potential dose reductions of 10-to 100-fold to each staff member with appropriate use of shielding, choice of imaging method, staff position in the room and complex interplay of other factors. The digital dosemeters were well tolerated by staff. Results highlight some unique radiation safety challenges in PIR that arise from dose increases with magnification use and close proximity of staff to the X-ray beam. (authors)

  2. Use of digital dosemeters for supporting staff radiation safety in paediatric interventional radiology suites.

    Science.gov (United States)

    McNeil, Sarah M; Lai, Priscilla; Connolly, Bairbre L; Gordon, Christopher L

    2013-12-01

    Modern-day interventional radiology (IR) procedures impart a wide range of occupational radiation doses to team members. Unlike thermoluminescent badges, digital dosemeters provide real-time dose readings, making them ideal for identifying different components during IR procedures, which influence staff radiation safety. This study focused solely on paediatric IR (PIR) cases. Digital dosemeters measured the impact of imaging modality, shielding, patient and operator specific factors, on the radiation dose received during various simulated and real live PIR procedures. They recorded potential dose reductions of 10- to 100-fold to each staff member with appropriate use of shielding, choice of imaging method, staff position in the room and complex interplay of other factors. The digital dosemeters were well tolerated by staff. Results highlight some unique radiation safety challenges in PIR that arise from dose increases with magnification use and close proximity of staff to the X-ray beam.

  3. Identification of the key structural motifs involved in HspB8/HspB6-Bag3 interaction

    NARCIS (Netherlands)

    Fuchs, Margit; Poirier, Dominic J.; Seguin, Samuel J.; Lambert, Herman; Carra, Serena; Charette, Steve J.; Landry, Jacques

    2010-01-01

    The molecular chaperone HspB8 [Hsp (heat-shock protein) B8] is member of the B-group of Hsps. These proteins bind to unfolded or misfolded proteins and protect them from aggregation. HspB8 has been reported to form a stable molecular complex with the chaperone cohort protein Bag3 (Bcl-2-associated

  4. Photon and fast neutron dosimetry using aluminium oxide thermoluminescence dosemeters in a pool-type research reactor

    International Nuclear Information System (INIS)

    Santos, J.P.; Marques, J.G.; Fernandes, A.C.; Osvay, M.

    2007-01-01

    Al 2 O 3 :Mg,Y thermoluminescence (TL) dosemeters were used to measure photon and fast neutron doses in the mixed radiation field of the Portuguese Research Reactor. The dosemeters were irradiated in core positions under a photon dose rate of the order of 10 4 Gy/h and a fast neutron flux in the range of 10 9 -10 11 n/cm 2 /s. In order to evaluate the ability of the TL dosemeters for mixed field dosimetry at the research reactor, the measurements were compared with results obtained via conventional methods. The agreement between the different methods is better than 13% for the determination of photon doses and within 5% for the determination of neutron fluxes in mixed fields

  5. Effect of some parameters in the response of the Perspex 3042, Lot L amber dosemeters

    International Nuclear Information System (INIS)

    Prieto M, E.F.; Barrera G, G.

    2004-01-01

    The answer of the dosimetric systems is affected by several factors, for what should know as these factors they influence in each one of the different dosimetric systems and by this way to minimize its effect in the value of the absorbed dose and to obtain exact dose values. One of the dosimetric systems more used in the high dose dosimetry like routine dosemeter for the control of the irradiation process are the Perspex dosemeters, for their speed in the obtaining the information, their easy manipulation and the precision that they present. To this dosemeters group they belong the same as the Red and Clear the Amber, which are adequate for the measurement of the radiation dose in the range of high doses. The objective of the present work is to obtain the calibration curves of the dosemeters Amber Perspex 3042, Lot L under our work conditions, like they are the irradiation temperatures and of storage and to know the influence of the rate dose in the value of the absorbed dose for different measurement wavelengths, as well as, the relationship among the one post-irradiation time and the specific absorbance value induced in function of the absorbed dose. (Author)

  6. Identification of the divergent calmodulin binding motif in yeast Ssb1/Hsp75 protein and in other HSP70 family members.

    Science.gov (United States)

    Heinen, R C; Diniz-Mendes, L; Silva, J T; Paschoalin, V M F

    2006-11-01

    Yeast soluble proteins were fractionated by calmodulin-agarose affinity chromatography and the Ca2+/calmodulin-binding proteins were analyzed by SDS-PAGE. One prominent protein of 66 kDa was excised from the gel, digested with trypsin and the masses of the resultant fragments were determined by MALDI/MS. Twenty-one of 38 monoisotopic peptide masses obtained after tryptic digestion were matched to the heat shock protein Ssb1/Hsp75, covering 37% of its sequence. Computational analysis of the primary structure of Ssb1/Hsp75 identified a unique potential amphipathic alpha-helix in its N-terminal ATPase domain with features of target regions for Ca2+/calmodulin binding. This region, which shares 89% similarity to the experimentally determined calmodulin-binding domain from mouse, Hsc70, is conserved in near half of the 113 members of the HSP70 family investigated, from yeast to plant and animals. Based on the sequence of this region, phylogenetic analysis grouped the HSP70s in three distinct branches. Two of them comprise the non-calmodulin binding Hsp70s BIP/GR78, a subfamily of eukaryotic HSP70 localized in the endoplasmic reticulum, and DnaK, a subfamily of prokaryotic HSP70. A third heterogeneous group is formed by eukaryotic cytosolic HSP70s containing the new calmodulin-binding motif and other cytosolic HSP70s whose sequences do not conform to those conserved motif, indicating that not all eukaryotic cytosolic Hsp70s are target for calmodulin regulation. Furthermore, the calmodulin-binding domain found in eukaryotic HSP70s is also the target for binding of Bag-1 - an enhancer of ADP/ATP exchange activity of Hsp70s. A model in which calmodulin displaces Bag-1 and modulates Ssb1/Hsp75 chaperone activity is discussed.

  7. Identification of the divergent calmodulin binding motif in yeast Ssb1/Hsp75 protein and in other HSP70 family members

    Directory of Open Access Journals (Sweden)

    R.C. Heinen

    2006-11-01

    Full Text Available Yeast soluble proteins were fractionated by calmodulin-agarose affinity chromatography and the Ca2+/calmodulin-binding proteins were analyzed by SDS-PAGE. One prominent protein of 66 kDa was excised from the gel, digested with trypsin and the masses of the resultant fragments were determined by MALDI/MS. Twenty-one of 38 monoisotopic peptide masses obtained after tryptic digestion were matched to the heat shock protein Ssb1/Hsp75, covering 37% of its sequence. Computational analysis of the primary structure of Ssb1/Hsp75 identified a unique potential amphipathic alpha-helix in its N-terminal ATPase domain with features of target regions for Ca2+/calmodulin binding. This region, which shares 89% similarity to the experimentally determined calmodulin-binding domain from mouse, Hsc70, is conserved in near half of the 113 members of the HSP70 family investigated, from yeast to plant and animals. Based on the sequence of this region, phylogenetic analysis grouped the HSP70s in three distinct branches. Two of them comprise the non-calmodulin binding Hsp70s BIP/GR78, a subfamily of eukaryotic HSP70 localized in the endoplasmic reticulum, and DnaK, a subfamily of prokaryotic HSP70. A third heterogeneous group is formed by eukaryotic cytosolic HSP70s containing the new calmodulin-binding motif and other cytosolic HSP70s whose sequences do not conform to those conserved motif, indicating that not all eukaryotic cytosolic Hsp70s are target for calmodulin regulation. Furthermore, the calmodulin-binding domain found in eukaryotic HSP70s is also the target for binding of Bag-1 - an enhancer of ADP/ATP exchange activity of Hsp70s. A model in which calmodulin displaces Bag-1 and modulates Ssb1/Hsp75 chaperone activity is discussed.

  8. A portable versatile x-and γ-ray dosemeter with digital display for medical use

    International Nuclear Information System (INIS)

    Sankaran, A.; Gangadharan, P.

    1980-01-01

    A multipurpose dosemeter based on analogue-to-digital (A-D) conversion has been developed using solid state devices, micropower integrated circuits and displays. The A-D converter combines the features of a MOSFET electrometer, a voltage-to-frequency converter, the automatic Townsend balance, LED(LCD) display for exposure, analogue output and has a voltage-measuring accuracy of +-O.1% FS+-1 digit. The dosemeter which is designed to measure a wide range of X- and γ-ray exposure rates (1 mRh -1 to 1000 R min -1 ) and exposures (1 mR to 1000 R) with a variety of air-equivalent ionisation chambers, is compact, rugged and battery or AC mains powered. It is designed to provide trouble-free performance, easy operation and maintenance and to be independent of climatic conditions. Combining the features of a survey meter, dosemeter and a radioisotope calibrator, it can be fabricated using the facilities locally available in hospitals or universities. (author)

  9. Viability of the Fricke dosemeter doped with methylene blue

    International Nuclear Information System (INIS)

    Souza, V.L.B.; Santos, C.D.A.; Rodrigues, K.R.G.; Cunha, M.S.; Figueiredo, M.D.C.; Melo, R.T.

    2009-01-01

    This work aims to find the possible utilization of the Fricke dosemeter doped with methylene blue (FMB) for the dosimetry of photodynamic therapy. The FMB was irradiated wit X rays and light emitted diodes demonstrating positive answers to the stimulus, being probably to be used for dosimetric objectives

  10. Exposure levels to radiation in a nuclear medicine laboratory: measurements with thermoluminescence dosemeters

    International Nuclear Information System (INIS)

    Ruiz J, A.

    2000-01-01

    Since 1996 in the Nuclear medicine Department and another routine and research departments of the National Institute of Medical and Nutrition Sciences (INCMNSZ) are working at least with 12 radioactive sources opened and sealed. However, it was unknown if with the Tl personal dosemeters with lithium fluoride crystals (LiF), could be possible to receive information about the equivalent dose for each radionuclide or if there was some radionuclide that by being low energy emissor or beta energy emissor, it did not represent an ionization power sufficient to excite the crystals of the thermoluminescent dosemeters (DTL). In this work the obtained results with control dosemeters of diverse source opened or sealed are shown, which were put at 1 cm of the LiF crystals during a time exposure 18 hours. Therefore the objective of this work is to verify which sources excite or not to DTL crystals and taking the pertinent safety measures for each radionuclide. The conclusion is that the majority of dosemeters were excited by beta or gamma radiation of the radionuclides and that LiF crystals are able to receive equivalent doses until 1200 mSv, being this a guarantee for the staff, that in an any moment could be exposed to high dose in his working day. Also it was corroborated that the radionuclides more energizer are: iodine-131, iodine-125 and sodium-22 while the phosphorus-32 must be managed with careful, since the exposure to hands can result significant, just like the technetium-99m ( 99m Tc). (Author)

  11. HSP90 Shapes the Consequences of Human Genetic Variation.

    Science.gov (United States)

    Karras, Georgios I; Yi, Song; Sahni, Nidhi; Fischer, Máté; Xie, Jenny; Vidal, Marc; D'Andrea, Alan D; Whitesell, Luke; Lindquist, Susan

    2017-02-23

    HSP90 acts as a protein-folding buffer that shapes the manifestations of genetic variation in model organisms. Whether HSP90 influences the consequences of mutations in humans, potentially modifying the clinical course of genetic diseases, remains unknown. By mining data for >1,500 disease-causing mutants, we found a strong correlation between reduced phenotypic severity and a dominant (HSP90 ≥ HSP70) increase in mutant engagement by HSP90. Examining the cancer predisposition syndrome Fanconi anemia in depth revealed that mutant FANCA proteins engaged predominantly by HSP70 had severely compromised function. In contrast, the function of less severe mutants was preserved by a dominant increase in HSP90 binding. Reducing HSP90's buffering capacity with inhibitors or febrile temperatures destabilized HSP90-buffered mutants, exacerbating FA-related chemosensitivities. Strikingly, a compensatory FANCA somatic mutation from an "experiment of nature" in monozygotic twins both prevented anemia and reduced HSP90 binding. These findings provide one plausible mechanism for the variable expressivity and environmental sensitivity of genetic diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Study of a selection of 10 historical types of dosemeter: variation of the response to Hp(10) with photon energy and geometry of exposure.

    Science.gov (United States)

    Thierry-Chef, I; Pernicka, F; Marshall, M; Cardis, E; Andreo, P

    2002-01-01

    An international collaborative study of cancer risk among workers in the nuclear industry is tinder way to estimate direetly the cancer risk following protracted low-dose exposure to ionising radiation. An essential aspect of this study is the characterisation and quantification of errors in available dose estimates. One major source of errors is dosemeter response in workplace exposure conditions. Little information is available on energy and geometry response for most of the 124 different dosemeters used historically in participating facilities. Experiments were therefore set up to assess this. using 10 dosemeter types representative of those used over time. Results show that the largest errors were associated with the response of early dosemeters to low-energy photon radiation. Good response was found with modern dosemeters. even at low energy. These results are being used to estimate errors in the response for each dosemeter type, used in the participating facilities, so that these can be taken into account in the estimates of cancer risk.

  13. Expression of HSP27, HSP72 and MRP proteins in in vitro co-culture ...

    Indian Academy of Sciences (India)

    We studied the expression of inducible heat shock protein (HSP27, HSP72) and multidrug-resistance protein (MRP) in co-cultures of human colon carcinoma cell spheroids obtained from different grades of tumour with normal human colon epithelium, myofibroblast and endothelial cell monolayers. We also measured the ...

  14. Effect of vibrational stress and spaceflight on regulation of heat shock proteins hsp70 and hsp27 in human lymphocytes (Jurkat)

    Science.gov (United States)

    Cubano, L. A.; Lewis, M. L.

    2001-01-01

    Heat shock protein levels are increased in cells as a result of exposure to stress. To determine whether heat shock protein regulation could be used to evaluate stress in cells during spaceflight, the response of Jurkat cells to spaceflight and simulated space shuttle launch vibration was investigated by evaluating hsp70 and hsp27 gene expression. Gene expression was assessed by reverse transcription-polymerase chain reaction using mRNA extracted from vibrated, nonvibrated, space-flown, and ground control cells. Results indicate that mechanical stresses of vibration and low gravity do not up-regulate the mRNA for hsp70, although the gene encoding hsp27 is up-regulated by spaceflight but not by vibration. In ground controls, the mRNA for hsp70 and hsp27 increased with time in culture. We conclude that hsp70 gene expression is a useful indicator of stress related to culture density but is not an indicator of the stresses of launch vibration or microgravity. Up-regulation of hsp27 gene expression in microgravity is a new finding.

  15. Characterization of a two-component thermoluminescent albedo dosemeter according to ISO 21909

    Energy Technology Data Exchange (ETDEWEB)

    Martins, M.M., E-mail: marcelo@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN), Av. Salvador Allende s/n, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Mauricio, C.L.P., E-mail: claudia@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN), Av. Salvador Allende s/n, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Pereira, W.W., E-mail: walsan@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN), Av. Salvador Allende s/n, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Silva, A.X. da, E-mail: ademir@con.ufrj.b [Coordenacao dos Programas de Pos-Graduacao em Engenharia, COPPE/PEN Caixa Postal 68509, CEP 21941-972, Rio de Janeiro, RJ (Brazil)

    2011-05-15

    A two-component thermoluminescent albedo neutron monitoring system was developed at Instituto de Radioprotecao e Dosimetria, Brazil. As there is no Brazilian regulation for neutron individual monitoring service, the system was tested according to the ISO 21909 standard. This standard provides performance and test requirements for determining the acceptability of personal neutron dosemeters to be used for the measurement of personal dose equivalent, H{sub p}(10), in neutron fields with energies ranging from thermal to 20 MeV. Up to 40 dosemeters were used in order to accomplish satisfactorily the requirements of some tests. Despite operational difficulties, this albedo system passed all ISO 21909 performance requirements. The results and problems throughout this characterization are discussed in this paper.

  16. Overexpression of GmHsp90s, a heat shock protein 90 (Hsp90 gene family cloning from soybean, decrease damage of abiotic stresses in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Jinyan Xu

    Full Text Available Hsp90 is one of the most conserved and abundant molecular chaperones and is an essential component of the protective stress response; however, its roles in abiotic stress responses in soybean (Glycine max remain obscure. Here, 12 GmHsp90 genes from soybean were identified and found to be expressed and to function differentially under abiotic stresses. The 12 GmHsp90 genes were isolated and named GmHsp90A1-GmHsp90A6, GmHsp90B1, GmHsp90B2, GmHsp90C1.1, GmHsp90C1.2, GmHsp90C2.1 and GmHsp90C2.2 based on their characteristics and high homology to other Hsp90s according to a new nomenclature system. Quantitative real-time PCR expression data revealed that all the genes exhibited higher transcript levels in leaves and could be strongly induced under heat, osmotic and salt stress but not cold stress. Overexpression of five typical genes (GmHsp90A2, GmHsp90A4, GmHsp90B1, GmHsp90C1.1 and GmHsp90C2.1 in Arabidopsis thaliana provided useful evidences that GmHsp90 genes can decrease damage of abiotic stresses. In addition, an abnormal accumulation of proline was detected in some transgenic Arabidopsis plants suggested overexpressing GmHsp90s may affect the synthesis and response system of proline. Our work represents a systematic determination of soybean genes encoding Hsp90s, and provides useful evidence that GmHsp90 genes function differently in response to abiotic stresses and may affect the synthesis and response system of proline.

  17. Study on routines and procedures of calibration of clinical dosemeter on gamma radiation beams at the IPEN-CNEN/SP, Brazil

    International Nuclear Information System (INIS)

    Damatto, Willian B.; Potiens, Maria da Penha A.; Santos, Gelson P.; Vivolo, Vitor

    2009-01-01

    The calibration consists in the comparison of the equipment to be calibrated with other equipment already calibrated by another standard, which means the equipment that will accomplish shall be considered secondary or tertiary, depending on the calibration that will be accomplished. As the clinical dosemeters are used for quality control services in the hospitals, these dosemeters need a reliable measurement precision. Therefore, this work intends to demonstrate the importance of the clinical dosemeter and the calibration, requiring special care face to all clinical set

  18. Hsp70/Hsp90 organising protein (hop): beyond interactions with chaperones and prion proteins.

    Science.gov (United States)

    Baindur-Hudson, Swati; Edkins, Adrienne L; Blatch, Gregory L

    2015-01-01

    The Hsp70/Hsp90 organising protein (Hop), also known as stress-inducible protein 1 (STI1), has received considerable attention for diverse cellular functions in both healthy and diseased states. There is extensive evidence that intracellular Hop is a co-chaperone of the major chaperones Hsp70 and Hsp90, playing an important role in the productive folding of Hsp90 client proteins. Consequently, Hop is implicated in a number of key signalling pathways, including aberrant pathways leading to cancer. However, Hop is also secreted and it is now well established that Hop also serves as a receptor for the prion protein, PrP(C). The intracellular and extracellular forms of Hop most likely represent two different isoforms, although the molecular determinants of these divergent functions are yet to be identified. There is also a growing body of research that reports the involvement of Hop in cellular activities that appear independent of either chaperones or PrP(C). While Hop has been shown to have various cellular functions, its biological function remains elusive. However, recent knockout studies in mammals suggest that Hop has an important role in embryonic development. This review provides a critical overview of the latest molecular, cellular and biological research on Hop, critically evaluating its function in healthy systems and how this function is adapted in diseases states.

  19. Performance of Panasonic ZP-1460 Electronic Personal Dosemeter under Exposure Conditions Likely to be Found at Fukushima Daiichi Nuclear Power Plant

    Science.gov (United States)

    Tsujimura, Norio; Yoshida, Tadayoshi; Hoshi, Katsuya; Momose, Takumaro

    A study on the performance of the Panasonic ZP-1460 electronic personal dosemeter, the model used in the aftermath of the Fukushima Daiichi nuclear power plant accident in March 2011, was conducted under actual exposure situations likely encountered in the plant. The tests pertained to (1) the dose rate response over dose rates >100 mSv/h and (2) the angular response on an anthropomorphic phantom exposed to the rotational and isotropic irradiation geometries. The test results confirmed that the dosemeter provides Hp(10) as a reasonably close estimate of the effective dose for any exposure geometries. The dosemeter response data evaluated in this study can be utilized for converting dosemeter readings to the absorbed dose to any organs and tissues for epidemiologic purposes.

  20. Calibration of a special neutron dosemeter based on solid-state track detectors and fission radiators in various neutron fields

    International Nuclear Information System (INIS)

    Doerschel, B.; Krusche, M.; Schuricht, V.

    1980-01-01

    The calibration of a personnel neutron dosemeter in different neutron fields is described. The badge-like dosemeter contains 5 detectors: polycarbonate foil (10 μm, Makrofol KG), 232 Th, natural uranium, natural uranium with boron, and natural uranium with cadmium. Detector sensitivity and calibration factors have been calculated and measured in radiation fields of 252 Cf fission neutrons, WWR-S reactor neutrons with and without Cd and Fe shielding, 3-MeV (d,t) generator neutrons, and 238 PuBe neutrons. Measurement range and achievable accuracy are discussed from the point of view of applying the dosemeter in routine and emergency uses

  1. The expression and correlation of Hsp 70 and Hsp 27 in serous middle ear effusion fluids of pediatric patients-a preliminary study.

    Science.gov (United States)

    Min, Hyun Jin; Choe, Ji Won; Chang, Moon Young; Kim, Kyung Soo; Lee, Sei Young; Mun, Seog-Kyun

    2017-10-01

    Several cytokines and innate immune-associated molecules are present in middle ear effusions, but damage-associated molecular patterns (DAMPs) in middle ear effusion have not been studied. Therefore, we evaluated the role of heat shock proteins (Hsps) in the development of otitis media with effusion (OME). Serous middle ear effusions from 22 pediatric patients who were diagnosed with OME and underwent ventilation tube insertion from June 2015 to March 2017 were evaluated in our study. The levels of Hsp 90, 70, 27, IL-8, and TNF-α in effusion fluids were evaluated by enzyme-linked immunosorbent assays. The associations between the levels of these molecules and the degree of tympanic membrane inflammation were statistically evaluated. Finally, the relationships among these molecules were also evaluated. Hsp 70 and Hsp 27 were detected in all middle ear effusions, but Hsp 90 was detected in only five effusion fluid samples. IL-8 was also detected in all middle ear effusions, but TNF-α was detected in only four effusion fluid samples. When we compared the degree of tympanic membrane inflammation with the levels of Hsp 70, Hsp 27, and IL-8, which were detected in all effusion fluids, we could not find statistical significance. However, Hsp 70, Hsp 27, and IL-8 were significantly associated with each other (p effusions. Furthermore, the levels of Hsp 70 and Hsp 27 were positively correlated with each other, and were also positively associated with the neutrophil chemoattractant, IL-8. Our findings suggested that Hsp 70 and Hsp 27 might be involved in the pathophysiology of pediatric OME. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Imbalance of Hsp70 family variants fosters tau accumulation.

    Science.gov (United States)

    Jinwal, Umesh K; Akoury, Elias; Abisambra, Jose F; O'Leary, John C; Thompson, Andrea D; Blair, Laura J; Jin, Ying; Bacon, Justin; Nordhues, Bryce A; Cockman, Matthew; Zhang, Juan; Li, Pengfei; Zhang, Bo; Borysov, Sergiy; Uversky, Vladimir N; Biernat, Jacek; Mandelkow, Eckhard; Gestwicki, Jason E; Zweckstetter, Markus; Dickey, Chad A

    2013-04-01

    Dysfunctional tau accumulation is a major contributing factor in tauopathies, and the heat-shock protein 70 (Hsp70) seems to play an important role in this accumulation. Several reports suggest that Hsp70 proteins can cause tau degradation to be accelerated or slowed, but how these opposing activities are controlled is unclear. Here we demonstrate that highly homologous variants in the Hsp70 family can have opposing effects on tau clearance kinetics. When overexpressed in a tetracycline (Tet)-based protein chase model, constitutive heat shock cognate 70 (Hsc70) and inducible Hsp72 slowed or accelerated tau clearance, respectively. Tau synergized with Hsc70, but not Hsp72, to promote microtubule assembly at nearly twice the rate of either Hsp70 homologue in reconstituted, ATP-regenerating Xenopus extracts supplemented with rhodamine-labeled tubulin and human recombinant Hsp72 and Hsc70. Nuclear magnetic resonance spectroscopy with human recombinant protein revealed that Hsp72 had greater affinity for tau than Hsc70 (I/I0 ratio difference of 0.3), but Hsc70 was 30 times more abundant than Hsp72 in human and mouse brain tissue. This indicates that the predominant Hsp70 variant in the brain is Hsc70, suggesting that the brain environment primarily supports slower tau clearance. Despite its capacity to clear tau, Hsp72 was not induced in the Alzheimer's disease brain, suggesting a mechanism for age-associated onset of the disease. Through the use of chimeras that blended the domains of Hsp72 and Hsc70, we determined that the reason for these differences between Hsc70 and Hsp72 with regard to tau clearance kinetics lies within their C-terminal domains, which are essential for their interactions with substrates and cochaperones. Hsp72 but not Hsc70 in the presence of tau was able to recruit the cochaperone ubiquitin ligase CHIP, which is known to facilitate the ubiquitination of tau, describing a possible mechanism of how the C-termini of these homologous Hsp70 variants

  3. Involvement of p27CIP/KIP in HSP25 or HSP70 Mediated Adaptive Response by Low Dose Radiation

    International Nuclear Information System (INIS)

    Seo, Hang Rhan; Lee, Yoon Jin; Lee, Su Jae; Bae, Sang woo; Lee, Yun Sil

    2005-01-01

    Adaptive responses that reduce the harmful effects of subsequent exposure to high-dose radiation have demonstrated in chromosome aberration, cell survival, sister chromatid exchanges, micronucleus induction, mutation and neoplastic transformation. The mechanisms and conditions for the adaptive response to radiation have not been clarified, although the continuous production of free radicals from radiation and other sources has stimulated cells to evolve a repair system for chromosome breaks. An alteration of the DNA molecule triggers the repair system, and frequent activation may increase the general repair capacity, irrespective of the cause of the damage. Besides, cell cycle regulation systems, antioxidant defense systems, molecular chaperone or stress-response systems. Our previous data showed that when cells were preirradiated with 1cGy, they showed the adaptive response. A reduction of apoptosis by low-dose preirradiation is another potential mechanism for this effect. We previously demonstrated that mouse RIF cells, which did not induce HSP25 and HSP70 did not exhibit a adaptive response after 1cGy preirradiation. whereas the thermoresistant TR cells, which expressed inducible HSP25 and HSP70 showed a response. Moreover, when HSP70 and HSP25 were transfected to RIF cells, the cells acquired adaptive response. In this study, to elucidate the mechanisms in induction of adaptiveresponse, we compared cell cycle distribution by low dose radiation after HSP25 or HSP70 transfected cells and p27CIP/KIP is responsible for the different induction of adaptive response

  4. Graphite mixed magnesium borate TL dosemeters for beta ray dosimetry

    DEFF Research Database (Denmark)

    Prokic, M; Christensen, Poul

    1984-01-01

    Sintered MgB4O7:Dy dosemeters with graphite contents from 1 to 10% were investigated for application for personnel dosimetry. Data are given on dose response, dose threshold, reproducibility, beta energy response and fading. Furthermore, results from practical field experiments are presented...

  5. Epigallocatechin-3-gallate suppresses the expression of HSP70 and HSP90 and exhibits anti-tumor activity in vitro and in vivo

    International Nuclear Information System (INIS)

    Tran, Phan LCHB; Kim, Soo-A; Choi, Hong Seok; Yoon, Jung-Hoon; Ahn, Sang-Gun

    2010-01-01

    Epigallocatechin-3-gallate (EGCG), one of the major catechins in green tea, is a potential chemopreventive agent for various cancers. The aim of this study was to examine the effect of EGCG on the expression of heat shock proteins (HSPs) and tumor suppression. Cell colony formation was evaluated by a soft agar assay. Transcriptional activity of HSP70 and HSP90 was determined by luciferase reporter assay. An EGCG-HSPs complex was prepared using EGCG attached to the cyanogen bromide (CNBr)-activated Sepharose 4B. In vivo effect of EGCG on tumor growth was examined in a xenograft model. Treatment with EGCG decreased cell proliferation and colony formation of MCF-7 human breast cancer cells. EGCG specifically inhibited the expression of HSP70 and HSP90 by inhibiting the promoter activity of HSP70 and HSP90. Pretreatment with EGCG increased the stress sensitivity of MCF-7 cells upon heat shock (44°C for 1 h) or oxidative stress (H 2 O 2 , 500 μM for 24 h). Moreover, treatment with EGCG (10 mg/kg) in a xenograft model resulted in delayed tumor incidence and reduced tumor size, as well as the inhibition of HSP70 and HSP90 expression. Overall, these findings demonstrate that HSP70 and HSP90 are potent molecular targets of EGCG and suggest EGCG as a drug candidate for the treatment of human cancer

  6. Crystal structures of the ATPase domains of four human Hsp70 isoforms: HSPA1L/Hsp70-hom, HSPA2/Hsp70-2, HSPA6/Hsp70B', and HSPA5/BiP/GRP78.

    Directory of Open Access Journals (Sweden)

    Magdalena Wisniewska

    2010-01-01

    Full Text Available The 70-kDa heat shock proteins (Hsp70 are chaperones with central roles in processes that involve polypeptide remodeling events. Hsp70 proteins consist of two major functional domains: an N-terminal nucleotide binding domain (NBD with ATPase activity, and a C-terminal substrate binding domain (SBD. We present the first crystal structures of four human Hsp70 isoforms, those of the NBDs of HSPA1L, HSPA2, HSPA5 and HSPA6. As previously with Hsp70 family members, all four proteins crystallized in a closed cleft conformation, although a slight cleft opening through rotation of subdomain IIB was observed for the HSPA5-ADP complex. The structures presented here support the view that the NBDs of human Hsp70 function by conserved mechanisms and contribute little to isoform specificity, which instead is brought about by the SBDs and by accessory proteins.This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1.

  7. Crystal structures of the ATPase domains of four human Hsp70 isoforms: HSPA1L/Hsp70-hom, HSPA2/Hsp70-2, HSPA6/Hsp70B', and HSPA5/BiP/GRP78.

    Science.gov (United States)

    Wisniewska, Magdalena; Karlberg, Tobias; Lehtiö, Lari; Johansson, Ida; Kotenyova, Tetyana; Moche, Martin; Schüler, Herwig

    2010-01-11

    The 70-kDa heat shock proteins (Hsp70) are chaperones with central roles in processes that involve polypeptide remodeling events. Hsp70 proteins consist of two major functional domains: an N-terminal nucleotide binding domain (NBD) with ATPase activity, and a C-terminal substrate binding domain (SBD). We present the first crystal structures of four human Hsp70 isoforms, those of the NBDs of HSPA1L, HSPA2, HSPA5 and HSPA6. As previously with Hsp70 family members, all four proteins crystallized in a closed cleft conformation, although a slight cleft opening through rotation of subdomain IIB was observed for the HSPA5-ADP complex. The structures presented here support the view that the NBDs of human Hsp70 function by conserved mechanisms and contribute little to isoform specificity, which instead is brought about by the SBDs and by accessory proteins. This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1.

  8. Systematic Proteomic Identification of the Heat Shock Proteins (Hsp) that Interact with Estrogen Receptor Alpha (ERα) and Biochemical Characterization of the ERα-Hsp70 Interaction.

    Science.gov (United States)

    Dhamad, Ahmed E; Zhou, Zhenqi; Zhou, Jianhong; Du, Yuchun

    2016-01-01

    Heat shock proteins (Hsps) are known to associate with estrogen receptors (ER) and regulate ER-mediated cell proliferation. Historically, the studies in this area have focused on Hsp90. However, some critical aspects of the Hsp-ERα interactions remain unclear. For example, we do not know which Hsps are the major or minor ERα interactants and whether or not different Hsp isoforms associate equally with ERα. In the present study, through a quantitative proteomic method we found that 21 Hsps and 3 Hsp cochaperones were associated with ERα in human 293T cells that were cultured in a medium containing necessary elements for cell proliferation. Four Hsp70s (Hsp70-1, Hsc70, Grp75, and Grp78) were the most abundant Hsps identified to associate with ERα, followed by two Hsp90s (Hsp90α and Hsp90β) and three Hsp110s (Hsp105, HspA4, and HspA4L). Hsp90α was found to be 2-3 times more abundant than Hsp90β in the ERα-containing complexes. Among the reported Hsp cochaperones, we detected prostaglandin E synthase 3 (p23), peptidyl-prolyl cis-trans isomerase FKBP5 (FKBP51), and E3 ubiquitin-protein ligase CHIP (CHIP). Studies with the two most abundant ERα-associated Hsps, Hsp70-1 and Hsc70, using human breast cancer MCF7 cells demonstrate that the two Hsps interacted with ERα in both the cytoplasm and nucleus when the cells were cultured in a medium supplemented with fetal bovine serum and phenol red. Interestingly, the ERα-Hsp70-1/Hsc70 interactions were detected only in the cytoplasm but not in the nucleus under hormone starvation conditions, and stimulation of the starved cells with 17β-estradiol (E2) did not change this. In addition, E2-treatment weakened the ERα-Hsc70 interaction but had no effect on the ERα-Hsp70-1 interaction. Further studies showed that significant portions of Hsp70-1 and Hsc70 were associated with transcriptionally active chromatin and inactive chromatin, and the two Hsps interacted with ERα in both forms of the chromatins in MCF7 cells.

  9. Cloning and expression of the coding regions of the heat shock proteins HSP10 and HSP16 from Piscirickettsia salmonis

    Directory of Open Access Journals (Sweden)

    VIVIAN WILHELM

    2003-01-01

    Full Text Available The genes encoding the heat shock proteins HSP10 and HSP16 of the salmon pathogen Piscirickettsia salmonis have been isolated and sequenced. The HSP10 coding sequence is located in an open reading frame of 291 base pairs encoding 96 aminoacids. The HSP16 coding region was isolated as a 471 base pair fragment encoding a protein of 156 aminoacids. The deduced aminoacid sequences of both proteins show a significant homology to the respective protein from other prokaryotic organisms. Both proteins were expressed in E. coli as fusion proteins with thioredoxin and purified by chromatography on Ni-column. A rabbit serum against P. salmonis total proteins reacts with the recombinant HSP10 and HSP16 proteins. Similar reactivity was determined by ELISA using serum from salmon infected with P. salmonis. The possibility of formulating a vaccine containing these two proteins is discussed

  10. ANTI-HSP60 and ANTI-HSP70 antibody levels and micro/ macrovascular complications in type 1 diabetes: the EURODIAB Study

    DEFF Research Database (Denmark)

    Gruden, G.; Bruno, G.; Chaturvedi, N.

    2009-01-01

    OBJECTIVES: The heat shock proteins 60 and 70 (HSP60, HSP70) play an important role in cytoprotection. Under stress conditions they are released into the circulation and elicit an immune response. Anti-HSP60 and anti-HSP70 antibody levels have been associated with cardiovascular disease. Type 1......-control study from the EURODIAB Study of 531 type 1 diabetic patients was performed. SUBJECTS: Cases (n = 363) were defined as those with one or more complications of diabetes; control subjects (n = 168) were all those with no evidence of any complication. We measured anti-HSP60 and anti-HSP70 antibody levels...... quartiles were associated with a 47% reduced odds ratio of micro/macrovascular complications, independently of conventional risk factors, markers of inflammation and endothelial dysfunction [odds ratio (OR) = 0.53, 95% confidence intervals (CI): 0.28-1.02]. CONCLUSIONS: In this large cohort of type 1...

  11. Determination of isodose curves in Radiotherapy using an Alanine/ESR dosemeter; Determinacion de curvas de isodosis en Radioterapia usando un dosimetro de Alanina/ESR

    Energy Technology Data Exchange (ETDEWEB)

    Chen, F.; Baffa, O.; Graeff, C.F.O. [Departamento de Fisica e Matematica. Universidade de Sao Paulo FFCLRP. 14040-901 Ribeirao Preto-SP (Brazil)

    1998-12-31

    It was studied the possible use of an Alanine/ESR dosemeter in the isodose curves mapping in normal treatments of Radiotherapy. It was manufactured a lot of 150 dosemeters with base in a mixture of D-L Alanine dust (80 %) and paraffin (20 %). Each dosemeter has 4.7 mm diameter and 12 mm length. A group of 100 dosemeters of the lot were arranged inside 50 holes of the slice 25 of the phantom Rando Man. The phantom irradiation was realized in two opposed projections (AP and PA) in Co-60 equipment. A group of 15 dosemeters was take of the same lot for obtaining the calibration curve in a 1-20 Gy range. After irradiation the signal of each dosemeter was measured in an ESR spectrometer operating in the X-band ({approx} 9.5 GHz) and the wideness of Alanine ESR spectra central line was correlated with the radiation dose. The wideness dose calibration curve resulted linear with a correlation coefficient 0.9996. The isodose curves obtained show a profile enough similar at comparing with the theoretical curves. (Author)

  12. Systematic errors in the readings of track etch neutron dosemeters caused by the energy dependence of response

    International Nuclear Information System (INIS)

    Tanner, R.J.; Thomas, D.J.; Bartlett, D.T.; Horwood, N.

    1999-01-01

    A study has been performed to assess the extent to which variations in the energy dependence of response of neutron personal dosemeters can cause systematic errors in readings obtained in workplace fields. This involved a detailed determination of the response functions of personal dosemeters used in the UK. These response functions were folded with workplace spectra to ascertain the under- or over-response in workplace fields

  13. Systematic errors in the readings of track etch neutron dosemeters caused by the energy dependence of response

    CERN Document Server

    Tanner, R J; Bartlett, D T; Horwood, N

    1999-01-01

    A study has been performed to assess the extent to which variations in the energy dependence of response of neutron personal dosemeters can cause systematic errors in readings obtained in workplace fields. This involved a detailed determination of the response functions of personal dosemeters used in the UK. These response functions were folded with workplace spectra to ascertain the under- or over-response in workplace fields.

  14. Use of a robotic manipulator in the simulation of the automation of a calibration process of dosemeters

    International Nuclear Information System (INIS)

    Benitez R, J.S.; Najera H, M.C.

    2002-01-01

    The development of a system based in a manipulative robot which simulates the operative sequence in a calibration process of dosemeters is presented. In this process it is performed the monitoring of the dosemeter positions and the calibrator by mean of an arm of articulated robot which develops the movement sequences and the taking a decision based on the information coming from the external sensors. (Author)

  15. Thermoluminescent dosemeters (TLD) exposed to high fluxes of gamma radiation, thermal neutrons and protons

    International Nuclear Information System (INIS)

    Gambarini, G.; Martini, M.; Meinardi, F.; Raffaglio, C.; Salvadori, P.; Scacco, A.; Sichirollo, A.E.

    1996-01-01

    Thermoluminescent dosemeters (TLD), widely experimented and utilized in personal dosimetry, have some advantageous characteristics which induce one to employ them also in radiotherapy. The new radiotherapy techniques are aimed at selectively depositing a high dose in cancerous tissues. This goal is reached by utilising both conventional and other more recently proposed radiation, such as thermal neutrons and heavy charged particles. In these inhomogeneous radiation fields a reliable mapping of the spatial distribution of absorbed dose is desirable, and the utilized dosemeters have to give such a possibility without notably perturbing the radiation field with the materials of the dosemeters themselves. TLDs, for their small dimension and their tissue equivalence for most radiation, give good support in the mapping of radiation fields. After exposure to the high fluxes of therapeutic beams, some commercial TL dosemeters have shown a loss of reliability. An investigation has therefore be performed, both on commercial and on laboratory made phosphors, in order to investigate their behaviour in such radiation fields. In particular the thermal neutron and gamma ray mixed field of the thermal column of a nuclear reactor, of interest for Boron Neutron Capture Therapy (B.N.C.T.) and a proton beam, of interest for proton therapy, were considered. Here some results obtained with new TL phosphors exposed in such radiation fields are presented, after a short description of some radiation damage effect on commercial LiF TLDs exposed in the (n th ,γ) field of the thermal column of a reactor. (author)

  16. Stressing Out Hsp90 in Neurotoxic Proteinopathies.

    Science.gov (United States)

    Inda, Carmen; Bolaender, Alexander; Wang, Tai; Gandu, Srinivasa R; Koren, John

    2016-01-01

    A toxic accumulation of proteins is the hallmark pathology of several neurodegenerative disorders. Protein accumulation is regularly prevented by the network of molecular chaperone proteins, including and especially Hsp90. For reasons not yet elucidated, Hsp90 and the molecular chaperones interact with, but do not degrade, these toxic proteins resulting in the pathogenic accumulation of proteins such as tau, in Alzheimer's Disease, and α-synuclein, in Parkinson's Disease. In this review, we describe the associations between Hsp90 and the pathogenic and driver proteins of several neurodegenerative disorders. We additionally describe how the inhibition of Hsp90 promotes the degradation of both mutant and pathogenic protein species in models of neurodegenerative diseases. We also examine the current state of Hsp90 inhibitors capable of crossing the blood-brain barrier; compounds which may be capable of slowing, preventing, and possible reversing neurodegenerative diseases.

  17. Molecular mechanisms of canalization: Hsp90 and beyond

    Indian Academy of Sciences (India)

    2006-03-26

    Mar 26, 2006 ... ... and regulatory circuits, accounting for the important role Hsp90 plays in ... by environmental stress, genetic or pharmaceutical targeting of Hsp90. The ... Here, we discuss the role of Hsp90 in canalization and organismal ...

  18. Influence of the PMMA and the ISO slab phantom for calibrating personal dosemeters

    International Nuclear Information System (INIS)

    Ginjaume, M.; Ortega, X.; Barbosa, A.

    2000-01-01

    Wide agreement has been achieved among the main Bodies and Organisations involved in standardisation of radiation protection, related to the operational quantities for personal dosimetry. Since their definition in 1985, several reports have been published to clarify and define the experimental set up to be used for the calibration of dosemeters in terms of the above-mentioned quantities. Among these lines, ICRU 47 has listed five different phantoms that are used for calibration and whose results were accurate, within accepted uncertainties. However, to achieve uniformity in calibration procedures, the 30 cm x 30 cm x 15 cm PMMA slab phantom was recommended. The secondary calibration Laboratory from the Institut de Techniques Energetiques at the Technical University of Catalonia (UPC) agreed with the Spanish Nacional Laboratory to adopt the recommended PMMA phantom but to improve the accuracy of the calibration procedure, by introducing a correction factor for backscatter differences in a PMMA and an ICRU slab phantom. Such corrections were of the order of 8% for the low-energy X-ray qualities. Recently, ISO in ISO 4037-3, has proposed the ISO water slab phantom which consists of a 30 cm x 30 cm x 15 cm water phantom with PMMA walls (front wall 2.5 mm thick). This new phantom could be substituted by the above mentioned PMMA phantom for radiation qualities with mean energy equal or above that of 137 Cs. The aim of this work is to compare the influence of both phantoms when calibrating personal dosemeters with photons. A set of four TL personal dosemeters that are used in the UPC personal dosimetry Service and an electronic personal dosemeter (SIEMENS EPD-2) were calibrated in terms of H p (10) and H p (0.07) using the two proposed phantoms. Calibration factors for ISO X-ray narrow spectra, 137 Cs and 60 Co were experimentally obtained for each phantom and compared. In the TL measurements, differences were found to be within TL statistical uncertainty, provided that a

  19. Use of bubbles dosemeters to measure the neutrons leakage radiations around a medical accelerator

    International Nuclear Information System (INIS)

    Bourgois, L.

    1999-01-01

    In this study, the neutron component has been determined on a medical accelerator (Saturne 43F type accelerator) with the help of bubbles detectors marketed by the Bubble Technology Industry society. BD-PND type dosemeters with sensitivities from 0.1 to 0.23 bubbles/micro sievert have been used. These dosemeters have important advantages: they are small enough and then, homogeneously irradiated, they are insensitive to intense electromagnetic fields and to photons and electrons, they can used several times by compression, the reading of the device does not need expensive means and it is possible to multiply the measure points. (N.C.)

  20. Substrate Discrimination by ClpB and Hsp104

    Directory of Open Access Journals (Sweden)

    Danielle M. Johnston

    2017-05-01

    Full Text Available ClpB of E. coli and yeast Hsp104 are homologous molecular chaperones and members of the AAA+ (ATPases Associated with various cellular Activities superfamily of ATPases. They are required for thermotolerance and function in disaggregation and reactivation of aggregated proteins that form during severe stress conditions. ClpB and Hsp104 collaborate with the DnaK or Hsp70 chaperone system, respectively, to dissolve protein aggregates both in vivo and in vitro. In yeast, the propagation of prions depends upon Hsp104. Since protein aggregation and amyloid formation are associated with many diseases, including neurodegenerative diseases and cancer, understanding how disaggregases function is important. In this study, we have explored the innate substrate preferences of ClpB and Hsp104 in the absence of the DnaK and Hsp70 chaperone system. The results suggest that substrate specificity is determined by nucleotide binding domain-1.

  1. Hsp90: Friends, clients and natural foes.

    Science.gov (United States)

    Verma, Sharad; Goyal, Sukriti; Jamal, Salma; Singh, Aditi; Grover, Abhinav

    2016-08-01

    Hsp90, a homodimeric ATPase, is responsible for the correct folding of a number of newly synthesized polypeptides in addition to the correct folding of denatured/misfolded client proteins. It requires several co-chaperones and other partner proteins for chaperone activity. Due to the involvement of Hsp90-dependent client proteins in a variety of oncogenic signaling pathways, Hsp90 inhibition has emerged as one of the leading strategies for anticancer chemotherapeutics. Most of Hsp90 inhibitors blocks the N terminal ATP binding pocket and prevents the conformational changes which are essential for the loading of co-chaperones and client proteins. Several other inhibitors have also been reported which disrupt chaperone cycle in ways other than binding to N terminal ATP binding pocket. The Hsp90 inhibition is associated with heat shock response, mediated by HSF-1, to overcome the loss of Hsp90 and sustain cell survival. This review is an attempt to give an over view of all the important players of chaperone cycle. Copyright © 2016 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  2. Characterization of workplaces in interventional radiology using active dosemeters ALARA OD

    International Nuclear Information System (INIS)

    Prlic, I.; Milkovic-Kraus, S.; Mestrovic, T.; Suric-Mihic, M.; Vrtar, M.

    2005-01-01

    Full text: Because of progressive development and extended use of interventional radiology procedures it is highly recommended that all individuals involved in the process should be aware of the potential for both stochastic and deterministic effects due to occupational exposure. Interventional radiology procedures are essentially therapeutic and are performed by various medical specialists, not only by properly educated radiologists. As the procedures are performed in such a manner that certain number of medical staff are always needed near the patient, near the x- ray unit, ensuring 'safe' working environment in such radiation x-ray field geometry is a new challenge to regular radiation protection. In this work we are not primary concerned in relatively high doses delivered to patients undergoing interventional procedures. The patient is rather regarded as a secondary radiation source which emits scattered x-rays. The working staff, moving in mixed, primary and scattered x-ray field, is expected to be exposed to higher occupational doses due to combination of extended fluoroscopy times, elevated fluoroscopy currents and larger amount of radiographic images required. The protection of both patients and staff is to be upgraded. As passive dosemetes will give us clear knowledge only about the monthly integrated occupational dose, a reasonable doubt exists about the frequency and duration, of receiving the dose. Measuring dose rate is not a part of regular passive dosemeters monitoring systems. This is why we have developed active - electronic dosemeter device which provides us with additional dosimetry data about the frequency and duration of professional exposure burden. Digital dosemeter ALARA OD will record and integrate any occupational dose including the normal radiation background in the working area. It will record the time and duration of any fluoroscopic exposure done. This gives us the data about the dose rate of occupational radiation and frequency of

  3. Plasma Hsp72 (HSPA1A) and Hsp27 (HSPB1) expression under heat stress: influence of exercise intensity.

    Science.gov (United States)

    Périard, Julien D; Ruell, Patricia; Caillaud, Corinne; Thompson, Martin W

    2012-05-01

    Extracellular heat-shock protein 72 (eHsp72) expression during exercise-heat stress is suggested to increase with the level of hyperthermia attained, independent of the rate of heat storage. This study examined the influence of exercise at various intensities to elucidate this relationship, and investigated the association between eHsp72 and eHsp27. Sixteen male subjects cycled to exhaustion at 60% and 75% of maximal oxygen uptake in hot conditions (40°C, 50% RH). Core temperature, heart rate, oxidative stress, and blood lactate and glucose levels were measured to determine the predictor variables associated with eHsp expression. At exhaustion, heart rate exceeded 96% of maximum in both conditions. Core temperature reached 39.7°C in the 60% trial (58.9 min) and 39.0°C in the 75% trial (27.2 min) (P exercise may relate to the duration (i.e., core temperature attained) and intensity (i.e., rate of increase in core temperature) of exercise. Thus, the immuno-inflammatory release of eHsp72 and eHsp27 in response to exercise in the heat may be duration and intensity dependent.

  4. Eye lens monitoring for interventional radiology personnel: dosemeters, calibration and practical aspects of Hp(3) monitoring. A 2015 review

    International Nuclear Information System (INIS)

    Carinou, Eleftheria; Ferrari, Paolo; Bjelac, Olivera Ciraj; Gingaume, Merce; Merce, Marta Sans; O’Connor, Una

    2015-01-01

    A thorough literature review about the current situation on the implementation of eye lens monitoring has been performed in order to provide recommendations regarding dosemeter types, calibration procedures and practical aspects of eye lens monitoring for interventional radiology personnel. Most relevant data and recommendations from about 100 papers have been analysed and classified in the following topics: challenges of today in eye lens monitoring; conversion coefficients, phantoms and calibration procedures for eye lens dose evaluation; correction factors and dosemeters for eye lens dose measurements; dosemeter position and influence of protective devices. The major findings of the review can be summarised as follows: the recommended operational quantity for the eye lens monitoring is H p (3). At present, several dosemeters are available for eye lens monitoring and calibration procedures are being developed. However, in practice, very often, alternative methods are used to assess the dose to the eye lens. A summary of correction factors found in the literature for the assessment of the eye lens dose is provided. These factors can give an estimation of the eye lens dose when alternative methods, such as the use of a whole body dosemeter, are used. A wide range of values is found, thus indicating the large uncertainty associated with these simplified methods. Reduction factors from most common protective devices obtained experimentally and using Monte Carlo calculations are presented. The paper concludes that the use of a dosemeter placed at collar level outside the lead apron can provide a useful first estimate of the eye lens exposure. However, for workplaces with estimated annual equivalent dose to the eye lens close to the dose limit, specific eye lens monitoring should be performed. Finally, training of the involved medical staff on the risks of ionising radiation for the eye lens and on the correct use of protective systems is strongly recommended. (review)

  5. In-vivo dosimetry in radiotherapy: a comparison of the response of semiconductor and thermoluminescence (TLD700) dosemeters

    Energy Technology Data Exchange (ETDEWEB)

    Vynckier, S [Universite Catholique de Louvain, Brussels (Belgium). Cliniques Universitaires St. Luc; Greffe, J L; Loncol, T; Vanneste, F; Octave-Prignot, M; Denis, J M; De Patoul, N

    1995-12-01

    Semiconductor dosemeters and thermoluminescence dosemeters were calibrated in view of in-vivo dosimetry. Their response in a 8 MV photon beam and the respective correction factors for the treatment conditions were systematically studied. A total of 249 entrance and exit measurements with this dual detector combination were performed, mainly for treatments of the head and neck region. The resulting entrance and exit doses were compared with the expected doses at these positions, calculated on basis of the treatment and patient parameters. The results at the entrance showed a value of 1.010 (2.8% for the ratio of the measured to the calculated dose by diodes, 1.013) 4.9% for the ratio of the measured to the calculated dose by TLD and 1.003 (3.6% for the ratio of the measured dose by TLD to diodes. With respect the exit dose, the results were 0.998) 4.9%, 1.016 (7.7% and 1.019) 7.0% respectively after correction for the heterogeneity`s. Although the standard deviation for the TLD dosemeters is systematically larger than the standard deviation for the diodes, it is concluded that both dosemeters will yield similar results for-in-vivo dosimetry, if utilized under the same conditions.

  6. Production and immune response of recombinant Hsp60 and Hsp70 from the salmon pathogen Piscirickettsia salmonis

    Directory of Open Access Journals (Sweden)

    VIVIAN WILHELM

    2005-01-01

    Full Text Available We have isolated and sequenced the genes encoding the heat shock proteins 60 (Hsp60 and 70 (Hsp70 of the salmon pathogen Piscirickettsia salmonis. The sequence analysis revealed the expected two open reading frames that encode proteins with calculated molecular weights of 60,060 and 70,400. The proteins exhibit a 70-80% homology with other known prokaryotic Hsp60 and Hsp70 sequences. The coding regions have been expressed in E. coli as thioredoxin fusion proteins. Both recombinant proteins were shown to elicit a humoral response when injected intraperitoneally in Atlantic salmon and also conferred protection to fish challenged with P. salmonis. The present data will facilitate further studies on the involvement of heat shock proteins in protective immunity of fish to infection by P. salmonis and their potential use in recombinants vaccines against this intracellular pathogen.

  7. Mensuration of equivalent dose with personal dosemeters and instruments of radiological protection in the new operative magnitudes ICRU, for external fields of beta radiation. Part I. Study of the homogeneity of the response personal dosemeters leaves (cards G-1, TLD-100), in radiation fields of Co60

    International Nuclear Information System (INIS)

    Alvarez R, J.T.

    1994-01-01

    A sample of 40 composed personal dosemeters by cards model: G-l, (each card is made up of two TLD-100 crystals encapsulated in teflon), Harshaw trademark; those personal dosemeters present a free window and another with a filter of A1 of 171.7 mg cm -2 of mass thickness.The objective of the work is to select of this sample of 40 personal dosemeters a population with the same stocking and standard deviation. The technique used is that of comparison of stockings, (ANOVA; Variance Analysis, when samples of the same one were had size; and/or GLM, Widespread Lineal Models, when the samples were of different size), by means of the use of those Duncan statistics, SNK, Tukey, Gabriel; the results are validated proving the kindness of adjustment of the experimental data to a Normal distribution by means of the Shapiro-Wilks statistics.The experimental design used consists on a test of two vias: a via is the variable card with two levels, (crystal 1 and 2), the other via is the variable irradiation position with four levels, (LS=left superior, SR= right superior, LI= left Inferior, IR = right inferior). The irradiations carried out in blocks of four personal dosemeters in a gamma radiation beam range of Cobalt 60; carrying out three repetitions of the design. With object of proving the homogeneity of the filter of A1 in those personal dosemeters the experimental design was executed for those cards without personal dosemeters.They were also carried out tests of stockings to the readings of bottom and sensibility of the reader equipment, (Harshaw, model marks 2271), certain that doesn t exist differences for sequence of reading, but if in the stockings of the sensibility, (they were 4 different populations). The responses of the dosemeters were corrected subtracting him the reading correspondence of bottom and by sensibility of the reader equipment before subjecting them to the tests of stockings mentioned. Of the results of the tests of stockings for the cards with and

  8. Calibration of PADC-based neutron area dosemeters in the neutron field produced in the treatment room of a medical LINAC

    International Nuclear Information System (INIS)

    Bedogni, R.; Domingo, C.; Esposito, A.; Gentile, A.; García-Fusté, M.J.; San-Pedro, M. de; Tana, L.; D’Errico, F.; Ciolini, R.; Di Fulvio, A.

    2013-01-01

    PADC-based nuclear track detectors have been widely used as convenient ambient dosemeters in many working places. However, due to the large energy dependence of their response in terms of ambient dose equivalent (H ∗ (10)) and to the diversity of workplace fields in terms of energy distribution, the appropriate calibration of these dosemeters is a delicate task. These are among the reasons why ISO has introduced the 12789 Series of Standards, where the simulated workplace neutron fields are introduced and their use to calibrate neutron dosemeters is recommended. This approach was applied in the present work to the UAB PADC-based nuclear track detectors. As a suitable workplace, the treatment room of a 15 MV Varian CLINAC DHX medical accelerator, located in the Ospedale S. Chiara (Pisa), was chosen. Here the neutron spectra in two points of tests (1.5 m and 2 m from the isocenter) were determined with the INFN-LNF Bonner Sphere Spectrometer equipped with Dysprosium activation foils (Dy-BSS), and the values of H ∗ (10) were derived on this basis. The PADC dosemeters were exposed in these points. Their workplace specific H*(10) responses were determined and compared with those previously obtained in different simulated workplace or reference (ISO 8529) neutron fields. - Highlights: ► The neutron field of a medical LINAC was used to calibrate PADC neutron dosemeters. ► The neutron spectra were derived with a Dy-foil based Bonner Sphere Spectrometer. ► Workplace specific calibration factor were derived for the PADC dosemeters. ► These factors were compared with those obtained in reference neutron fields

  9. HSP20 phosphorylation and airway smooth muscle relaxation

    Directory of Open Access Journals (Sweden)

    Mariam Ba

    2009-06-01

    Full Text Available Mariam Ba1, Cherie A Singer1, Manoj Tyagi2, Colleen Brophy3, Josh E Baker4, Christine Cremo4, Andrew Halayko5, William T Gerthoffer21Department of Pharmacology, University of Nevada School of Medicine, Reno, NV, USA; 2Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, AL, USA; 3Harrington Department of Biochemistry, Arizona State University, Tempe, AZ, USA; 4Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV, USA; 5Departments of Physiology and Internal Medicine, University of Manitoba, Winnipeg, MB, CanadaAbstract: HSP20 (HSPB6 is a small heat shock protein expressed in smooth muscles that is hypothesized to inhibit contraction when phosphorylated by cAMP-dependent protein kinase. To investigate this hypothesis in airway smooth muscle (ASM we showed that HSP20 was constitutively expressed as well as being inducible in cultured hASM cells by treatment with 1 µM isoproterenol or 10 µM salmeterol. In contrast, a mixture of proinflammatory mediators (interleukin-1β, tumor necrosis factor α, and interferon γ inhibited expression of HSP20 by about 50% in 48 hours. To determine whether phosphorylation of HSP20 is sufficient to induce relaxation, canine tracheal smooth muscle was treated with a cell permeant phosphopeptide that mimics the phosphorylation of HSP20. The HSP20 phosphopeptide antagonized carbacholinduced contraction by 60% with no change in myosin light chain phosphorylation. Recombinant full length HSP20 inhibited skeletal actin binding to smooth muscle myosin subfragment 1 (S1, and recombinant cell permeant TAT-HSP20 S16D mutant reduced F-actin filaments in cultured hASM cells. Carbachol stimulation of canine tracheal smooth muscle tissue caused redistribution of HSP20 from large macromolecular complexes (200–500 kDa to smaller complexes (<60 kDa. The results are consistent with HSP20 expression and macromolecular structure being dynamically regulated in airway

  10. Intercomparison of Environmental Dosemeters Using Various TL Materials and Dosimetry Systems

    International Nuclear Information System (INIS)

    Crnic, B.; Gobec, S.; Zorko, B.; Knezevic, Z.; Majer, M.; Ranogajec-Komor, M.

    2013-01-01

    The aim of the present work was to compare the ambient dose equivalent (H*(10)) values determined at 20 sites around NPP Krško, using different thermoluminescence (TL) materials and various dosimetry systems. The H*(10) was measured by the CaF 2 :Mn (TLD-400) provided by the Jozef Stefan Institute (JSI) Ljubljana, Slovenia. These dosemeters were deployed in the environment in plastic bags and suspended inside the plastic bottles. On the other hand the Ruder Boskovic Institute (RBI), Zagreb, Croatia applied LiF:Mg,Cu,P (TLD-100H), CaF 2 :Mn, Al 2 O 3 :C TL detectors and radiophotoluminescence (RPL) glass dosemeters type SG1. They were placed at the same locations in as much as possible same conditions as JSI detectors. According to the protocol established for this intercomparison, the control and transport detectors (not deployed in the environment) were held in dark storage containers and used to determine the background radiation. The TL responses were corrected for individual sensitivity of the TL detectors which is an important factor after the calibration irradiations. The calibration irradiations were performed by 137Cs sources provided in Secondary Standard Dosimetry Laboratory facilities at the JSI and RBI. The results obtained by different TL materials and different dosimetry systems show interesting features especially concerning local environmental peculiarities. The H*(10) obtained by the dosemeters of various types deployed in the countryside fluctuate less than 10 %. The outcome should emphasize also in the manner that the results obtained and reported in the intercomparison are traceable to the primary standards.(author)

  11. Reduced Hsp70 and Glutamine in Pediatric Severe Malaria Anemia

    DEFF Research Database (Denmark)

    Kempaiah, Prakasha; Dokladny, Karol; Karim, Zachary

    2016-01-01

    by decreased HSPA1A, a heat shock protein (Hsp) 70 coding gene. Hsp70 is a ubiquitous chaperone that regulates Nuclear Factor-kappa B (NF-κB) signaling and production of pro-inflammatory cytokines known to be important in malaria pathogenesis (e.g., IL-1β, IL-6 and TNF-α). Since the role of host Hsp70...... in malaria pathogenesis is unexplored, we investigated Hsp70 and molecular pathways in children with SMA. Validation experiments revealed that leukocytic HSP70 transcripts were reduced in SMA relative to non-severe malaria, and that intraleukocytic hemozoin (PfHz) was associated with lower HSP70. HSP70...... was correlated with reticulocyte production and Hb. Since glutamine (Gln) up-regulates Hsp70, modulates NF-κB activation, and attenuates over-expression of pro-inflammatory cytokines, circulating Gln was measured in children with malaria. Reduced Gln was associated with increased risk of developing SMA...

  12. Role of membrane Hsp70 in radiation sensitivity of tumor cells

    International Nuclear Information System (INIS)

    Murakami, Naoya; Kühnel, Annett; Schmid, Thomas E.; Ilicic, Katarina; Stangl, Stefan; Braun, Isabella S.; Gehrmann, Mathias; Molls, Michael; Itami, Jun; Multhoff, Gabriele

    2015-01-01

    The major stress-inducible heat shock protein 70 (Hsp70) is frequently overexpressed in the cytosol and integrated in the plasma membrane of tumor cells via lipid anchorage. Following stress such as non-lethal irradiation Hsp70 synthesis is up-regulated. Intracellular located Hsp70 is known to exert cytoprotective properties, however, less is known about membrane (m)Hsp70. Herein, we investigate the role of mHsp70 in the sensitivity towards irradiation in tumor sublines that differ in their cytosolic and/or mHsp70 levels. The isogenic human colon carcinoma sublines CX + with stable high and CX − with stable low expression of mHsp70 were generated by fluorescence activated cell sorting, the mouse mammary carcinoma sublines 4 T1 (4 T1 ctrl) and Hsp70 knock-down (4 T1 Hsp70 KD) were produced using the CRISPR/Cas9 system, and the Hsp70 down-regulation in human lung carcinoma sublines H1339 ctrl/H1339 HSF-1 KD and EPLC-272H ctrl/EPLC-272H HSF-1 KD was achieved by small interfering (si)RNA against Heat shock factor 1 (HSF-1). Cytosolic and mHsp70 was quantified by Western blot analysis/ELISA and flow cytometry; double strand breaks (DSBs) and apoptosis were measured by flow cytometry using antibodies against γH2AX and real-time PCR (RT-PCR) using primers and antibodies directed against apoptosis related genes; and radiation sensitivity was determined using clonogenic cell surviving assays. CX + /CX − tumor cells exhibited similar cytosolic but differed significantly in their mHsp70 levels, 4 T1 ctrl/4 T1 Hsp70 KD cells showed significant differences in their cytosolic and mHsp70 levels and H1339 ctrl/H1339 HSF-1 KD and EPLC-272H ctrl/EPLC-272H HSF-1 KD lung carcinoma cell sublines had similar mHsp70 but significantly different cytosolic Hsp70 levels. γH2AX was significantly up-regulated in irradiated CX − and 4 T1 Hsp70 KD with low basal mHsp70 levels, but not in their mHsp70 high expressing counterparts, irrespectively of their cytosolic Hsp70 content. After

  13. Conversion factors for the ICRU dose equivalent quantities for calibrating radiation dosemeters

    International Nuclear Information System (INIS)

    Grosswendt, B.; Hohlfeld, K.; Kramer, H.M.; Selbach, H.J.

    1985-02-01

    Report describing the application of conversion factors for monoenergetic photon radiation and for X and gamma reference radiation used for dosemeter calibration with the aid of spherical or rectangular phantoms (environmental and individual monitoring). (DG) [de

  14. Improved Metabolic Control in Diabetes, HSP60, and Proinflammatory Mediators

    Directory of Open Access Journals (Sweden)

    Claudio Blasi

    2012-01-01

    Full Text Available The diabetes-atherosclerosis relationship remains to be fully defined. Repeated prolonged hyperglycemia, increased ROS production and endothelial dysfunction are important factors. One theory is that increased blood levels of heat shock protein (HSP60 are proinflammatory, through activation of innate immunity, and contribute to the progression of vascular disease. It was hypothesized that improvement of diabetes control in patients presenting with metabolic syndrome would lower HSP60, and anti-HSP60 antibody levels and decrease inflammatory markers. Paired sera of 17 Italian patients, before and after intensive treatment, were assayed for cytokines, HSP60 and anti-HSP60 antibodies. As expected, intensive treatment was associated with a decrease in HgbA1C (P<0.001 and BMI (P<0.001. After treatment, there was a significant decrease in IL-6 (P<0.05. HSP60 levels were before treatment −6.9+1.9, after treatment −7.1+2.0 ng/mL (P=ns. Overall HSP60 concentrations were lower than published reports. Anti-HSP60 antibody titers were high and did not decrease with treatment. In conclusion, improvement of diabetic control did not alter HSP60 concentrations or antiHSP60 antibody titers, but led to a reduction of IL-6 levels.

  15. Individual dosemeter with ionization chamber for intervention

    International Nuclear Information System (INIS)

    Prigent, M.

    1982-01-01

    The altogether intervention ratemeter-dosemeter is a device for work condition control and for dosimetry of intervention gang in hostile medium. A portable irradiation marker with ionization chamber either carried by staff, either put at the work post, delivers an information function of the surrounding irradiation field in which moves the intervention staff. The information is processed so as the absorbed dose rate and the absorbed dose are given simultaneously. The connection between the marker and the process device is made by a cable (up to 100m) or by radio link [fr

  16. EURADOS intercomparisons in external radiation dosimetry: similarities and differences among exercises for whole-body photon, whole-body neutron, extremity, eye-lens and passive area dosemeters

    International Nuclear Information System (INIS)

    Romero, Ana M.; Grimbergen, Tom; McWhan, Andrew; Stadtmann, Hannes; Fantuzzi, Elena; Clairand, Isabelle; Neumaier, Stefan; Dombrowski, Harald; Figel, Markus

    2016-01-01

    The European Radiation Dosimetry Group (EURADOS) has been organising dosimetry intercomparisons for many years in response to an identified requirement from individual monitoring services (IMS) for independent performance tests for dosimetry systems. The participation in intercomparisons gives IMS the opportunity to show compliance with their own quality management system, compare results with other participants and develop plans for improving their dosimetry systems. In response to growing demand, EURADOS has increased the number of intercomparisons for external radiation dosimetry. Most of these fit into the programme of self-financing intercomparisons for dosemeters routinely used by IMS. This programme is being coordinated by EURADOS working group 2 (WG2). Up to now, this programme has included four intercomparisons for whole-body dosemeters in photon fields, one for extremity dosemeters in photon and beta fields, and one for whole-body dosemeters in neutron fields. Other EURADOS working groups have organised additional intercomparisons including events in 2014 for eye-lens dosemeters and passive area dosemeters for environmental monitoring. In this paper, the organisation and achievements of these intercomparisons are compared in detail focusing on the similarities and differences in their execution. (authors)

  17. Re-assessment of dose from the Vinten extremity dosemeter

    International Nuclear Information System (INIS)

    O'Hagan, J.B.; Pearson, A.J.; Dutt, J.C.

    1989-01-01

    A procedure is described for re-assessing the dose from the Vinten extremity dosemeter using phototransferred thermoluminescence. The technique produces a linear response up to 50 Sv. The re-assessment efficiency is approximately 10% for the first re-assessment and 3-5% for the second re-assessment. The detection threshold values (at the 95% confidence level) are 3 mSv and 9 mSv respectively. (author)

  18. Systemic and mucosal immunization with Candida albicans hsp90 elicits hsp90-specific humoral response in vaginal mucosa which is further enhanced during experimental vaginal candidiasis.

    Science.gov (United States)

    Raska, Milan; Belakova, Jana; Horynova, Milada; Krupka, Michal; Novotny, Jiri; Sebestova, Martina; Weigl, Evzen

    2008-08-01

    The Candida albicans heat shock protein 90 kDa (hsp90-CA) is an important target for protective antibodies in disseminated candidiasis of experimental mice and humans. Hsp90-CA is present in the cell wall of Candida pseudohyphae or hyphae--typical pathogenic morphotypes in both mucosal and systemic Candida infections. However, the potential protective effects of hsp90-CA-specific antibodies in vaginal candidiasis has not yet been reported. In the present study we used various vaccine formulations (recombinant hsp90-CA protein and hsp90-CA-encoding DNA vaccine) and routes of administration (intradermal, intranasal, and intravenous) to induce both hsp90-CA-specific systemic and vaginal mucosa immune responses in experimental BALB/c mice. The results showed that intradermal recombinant hsp90-CA protein priming, followed by intranasal or intradermal recombinant hsp90-CA protein boosting induced significant increases in both serum and vaginal hsp90-CA-specific IgG and IgA antibodies compared to the control group, as well as enhanced hsp90-CA-specific splenocyte responses in vitro. In the intradermally boosted group, subsequent experimental vaginal Candida infection induced additional increases in the hsp90-CA specific IgG isotype, suggesting that Candida has the ability to induce a local hsp90-specific antibody (IgG) response during vulvovaginal candidiasis. Further work is required to elucidate the importance of immunity to highly conserved antigens during infection of the human female reproductive tract where a balance between immunity to and tolerance for commonly antigens such as hsp90 is necessary for the maintenance of fertility.

  19. A low-cost personal dosemeter based on optically stimulated luminescence (OSL) of common household salt (NaCl)

    International Nuclear Information System (INIS)

    Ekendahl, Daniela; Bulánek, Boris; Judas, Libor

    2016-01-01

    Salt represents a radiation sensitive material that can be used for dosimetry. The objective of this experimental study was to test a low-cost salt dosemeter that was designed for personnel that are not radiation workers, but can operate in low probability events resulting in a serious external radiation exposure. The dosemeter is based on use of optically stimulated luminescence (OSL) of a common household salt. Attention was concentrated on its energy and angular responses. The dosemeter was fixed to the ICRU slab phantom and irradiated by photons of reference radiation qualities (ISO 4037-1) with mean energies between 33 and 1250 keV. Angular response was investigated for angles of incidence from 0° to 80° for radiation qualities of N-150 (∼118 keV) and S-Cs (∼662 keV). Single-Aliquot Regenerative-dose analytical protocol was employed for dose reconstruction. The results were evaluated with respect to H_p(10) measurement. The salt dosemeter can provide reliable or reasonably conservative H_p(10) estimates in radiation fields where photon energies > 100 keV predominate, radiation incidence angles are from 0° to 80° and also for rotational geometry. Furthermore, a personal dose reconstruction trial was demonstrated. Relative deviation between the measured and reference H_p(10) values was 5.5%. A practical disadvantage of the method is the more demanding analytical protocol. - Highlights: • Common salt has a considerable potential for dosimetry based on use of OSL. • A simple salt personal dosemeter was designed and tested. • Photon energy and angular responses were satisfactory for purposes of accidental dosimetry. • Dose reconstruction trial proved the potential for reliable estimate of personal doses.

  20. Feasibility of a neutron detector-dosemeter based on single-event upsets in dynamic random-access memories

    International Nuclear Information System (INIS)

    Phillips, G.W.; August, R.A.; Campbell, A.B.; Nelson, M.E.; Guardala, N.A.; Price, J.L.; Moscovitch, M.

    2002-01-01

    The feasibility was investigated of a solid-state neutron detector/dosemeter based on single-event upset (SEU) effects in dynamic random-access memories (DRAMs), commonly used in computer memories. Such a device, which uses a neutron converter material to produce a charged particle capable of causing an upset, would be light-weight, low-power, and could be read simply by polling the memory for bit flips. It would have significant advantages over standard solid-state neutron dosemeters which require off-line processing for track etching and analysis. Previous efforts at developing an SEU neutron detector/dosemeter have suffered from poor response, which can be greatly enhanced by selecting a modern high-density DRAM chip for SEU sensitivity and by using a thin 10 B film as a converter. Past attempts to use 10 B were not successful because the average alpha particle energy was insufficient to penetrate to the sensitive region of the memory. This can be overcome by removing the surface passivation layer before depositing the 10 B film or by implanting 10B directly into the chip. Previous experimental data show a 10 3 increase in neutron sensitivity by chips containing borosilicate glass, which could be used in an SEU detector. The results are presented of simulations showing that the absolute efficiency of an SEU neutron dosemeter can be increased by at least a factor of 1000 over earlier designs. (author)

  1. Structure, Function and Regulation of the Hsp90 Machinery

    Directory of Open Access Journals (Sweden)

    Jing Li

    2013-06-01

    Full Text Available Heat shock protein 90 (Hsp90 is an ATP-dependent molecular chaperone which is essential in eukaryotes. It is required for the activation and stabilization of a wide variety of client proteins and many of them are involved in important cellular pathways. Since Hsp90 affects numerous physiological processes such as signal transduction, intracellular transport, and protein degradation, it became an interesting target for cancer therapy. Structurally, Hsp90 is a flexible dimeric protein composed of three different domains which adopt structurally distinct conformations. ATP binding triggers directionality in these conformational changes and leads to a more compact state. To achieve its function, Hsp90 works together with a large group of cofactors, termed co-chaperones. Co-chaperones form defined binary or ternary complexes with Hsp90, which facilitate the maturation of client proteins. In addition, posttranslational modifications of Hsp90, such as phosphorylation and acetylation, provide another level of regulation. They influence the conformational cycle, co-chaperone interaction, and inter-domain communications. In this review, we discuss the recent progress made in understanding the Hsp90 machinery.

  2. The Complex Function of Hsp70 in Metastatic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Juhasz, Kata; Lipp, Anna-Maria; Nimmervoll, Benedikt; Sonnleitner, Alois; Hesse, Jan; Haselgruebler, Thomas; Balogi, Zsolt, E-mail: zsolt.balogi@cbl.at [Center for Advanced Bioanalysis GmbH, Gruberstr. 40-42, A-4020 Linz (Austria)

    2013-12-20

    Elevated expression of the inducible heat shock protein 70 (Hsp70) is known to correlate with poor prognosis in many cancers. Hsp70 confers survival advantage as well as resistance to chemotherapeutic agents, and promotes tumor cell invasion. At the same time, tumor-derived extracellular Hsp70 has been recognized as a “chaperokine”, activating antitumor immunity. In this review we discuss localization dependent functions of Hsp70 in the context of invasive cancer. Understanding the molecular principles of metastasis formation steps, as well as interactions of the tumor cells with the microenvironment and the immune system is essential for fighting metastatic cancer. Although Hsp70 has been implicated in different steps of the metastatic process, the exact mechanisms of its action remain to be explored. Known and potential functions of Hsp70 in controlling or modulating of invasion and metastasis are discussed.

  3. Effective dose assessment in the maxillofacial region using thermoluminescent (TLD) and metal oxide semiconductor field-effect transistor (MOSFET) dosemeters: a comparative study

    NARCIS (Netherlands)

    Koivisto, J.; Schulze, D.; Wolff, J.E.H.; Rottke, D.

    2014-01-01

    Objectives: The objective of this study was to compare the performance of metal oxide semiconductor field-effect transistor (MOSFET) technology dosemeters with thermoluminescent dosemeters (TLDs) (TLD 100; Thermo Fisher Scientific, Waltham, MA) in the maxillofacial area. Methods: Organ and effective

  4. About the measurements systems with pen and thermoluminescent dosemeters; Sobre los sistemas de medicion con dosimetros de pluma y los termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Cortes I, M.E.; Ramirez G, F.P. [Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas 152. 07730 Mexico D.F. (Mexico)

    1998-12-31

    In this work it is presented dosimetric data obtained with pen and thermoluminescent dosemeters, which are used by the Occupational Exposure Personnel (OEP) of the Mexican Petroleum Institute (IMP)(1). It was marked several great characteristics as for example, the differences among units which use one and another dosemeter type. Likewise, it is given to know diverse problems that were had in the IMP at relating the data obtained with these dosemeters (which utilizes OEP) and the ICRP 60 recommendations 1990. One of the most important difficulties is to satisfy the recommended limits by ICRP, particularly those that are referring to the units and their complex calculations. With respect to the unities, the ICRP makes reference at the concepts `dose equivalent` and `effective dose` with the sievert unit, that the General Regulations for Radiological Safety associates with `dose equivalent` and `effective dose equivalent`. It was illustrated the type of dosimetric statistics which are obtained with the TLD lectures and a OEP pen dosemeter during 1997. (Author)

  5. Accumulation of hepatic Hsp70 and plasma cortisol in Oreochromis ...

    African Journals Online (AJOL)

    The hepatic isoforms Hsp70, Hsp74 and Hsp76 were identified and quantified from copper exposures. Long-term DDT exposure did not result in significant induction of hepatic Hsp70. An increase in plasma cortisol concentration was associated with a decrease in heat shock protein accumulation after cadmium exposure, ...

  6. PREFERENTIAL SECRETION OF INDUCIBLE HSP70 BY VITILIGO MELANOCYTES UNDER STRESS

    Science.gov (United States)

    Mosenson, Jeffrey A.; Flood, Kelsey; Klarquist, Jared; Eby, Jonathan M.; Koshoffer, Amy; Boissy, Raymond E.; Overbeck, Andreas; C.Tung, Rebecca; Poole, I. Caroline Le

    2014-01-01

    SUMMARY Inducible HSP70 (HSP70i) chaperones peptides from stressed cells, protecting them from apoptosis. Upon extracellular release, HSP70i serves an adjuvant function, enhancing immune responses to bound peptides. We questioned whether HSP70i differentially protects control and vitiligo melanocytes from stress and subsequent immune responses. We compared expression of HSP70i in skin samples, evaluated the viability of primary vitiligo and control melanocytes exposed to bleaching phenols, and measured secreted HSP70i. We determined whether HSP70i traffics to melanosomes to contact immunogenic proteins by cell fractionation, western blotting, electron microscopy and confocal microscopy. Viability of vitiligo and control melanocytes was equally affected under stress. However, vitiligo melanocytes secreted increased amounts of HSP70i in response to MBEH, corroborating with aberrant HSP70i expression in patient skin. Intracellular HSP70i colocalized with melanosomes, and more so in response to MBEH in vitiligo melanocytes. Thus whereas either agent is cytotoxic to melanocytes, MBEH preferentially induces immune responses to melanocytes. PMID:24354861

  7. Crystal structures of Hsp104 N-terminal domains from Saccharomyces cerevisiae and Candida albicans suggest the mechanism for the function of Hsp104 in dissolving prions

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Peng; Li, Jingzhi; Weaver, Clarissa; Lucius, Aaron; Sha, Bingdong

    2017-03-31

    Hsp104 is a yeast member of the Hsp100 family which functions as a molecular chaperone to disaggregate misfolded polypeptides. To understand the mechanism by which the Hsp104 N-terminal domain (NTD) interacts with its peptide substrates, crystal structures of the Hsp104 NTDs fromSaccharomyces cerevisiae(ScHsp104NTD) andCandida albicans(CaHsp104NTD) have been determined at high resolution. The structures of ScHsp104NTD and CaHsp104NTD reveal that the yeast Hsp104 NTD may utilize a conserved putative peptide-binding groove to interact with misfolded polypeptides. In the crystal structures ScHsp104NTD forms a homodimer, while CaHsp104NTD exists as a monomer. The consecutive residues Gln105, Gln106 and Lys107, and Lys141 around the putative peptide-binding groove mediate the monomer–monomer interactions within the ScHsp104NTD homodimer. Dimer formation by ScHsp104NTD suggests that the Hsp104 NTD may specifically interact with polyQ regions of prion-prone proteins. The data may reveal the mechanism by which Hsp104 NTD functions to suppress and/or dissolve prions.

  8. Evaluation of two personal dosemeters in polyenergetic mono- and multi-directional neutron fields

    International Nuclear Information System (INIS)

    Nunes, J. C.; Surette, R. A.

    2005-01-01

    The neutron dose-equivalent response of two commercially available electronic personal neutron dosemeters was studied in several laboratory-produced broad-spectrum neutron fields. Fluence-weighted mean energies ranged from 200 keV to 4 MeV; personal dose-equivalent rates ranged from 75 to 10 mSv h -1 ; and angles of incidence were multidirectional, 0 deg., 30 deg. and 60 deg.. Three of these fields have been shown previously to resemble ones found in CANDU (Canadian Deuterium Uranium is a registered trademark of the Atomic Energy of Canada Limited) power plant workplaces. Both dosemeters were found to perform reasonably well across the range of energy spectra and angles of incidence. One type of dosemeter displayed values of the personal dose equivalent that were, at worst, within a factor of ∼2 of the reference values and, at best, within a few per cent of the reference values. The other type displayed values of the personal dose equivalent that were consistently within unity and 20% of the reference values. Although the radiological performance of one was found to be more accurate, this device was also found to be the less rugged of the two. Some of the data acquired in this work were compared with results previously published by others. There was consistency between these sets of data. (authors)

  9. Quercetin suppresses heat shock-induced nuclear translocation of Hsp72

    Directory of Open Access Journals (Sweden)

    Antoni Gawron

    2011-08-01

    Full Text Available The effect of quercetin and heat shock on the Hsp72 level and distribution in HeLa cells was studied by Western blotting, indirect immunofluorescence and immunogold electron microscopy. In control cells and after quercetin treatment, Hsp72 was located both in the cytoplasm and in the nucleus in comparable amounts. After hyperthermia, the level of nuclear Hsp72 raised dramatically. Expression of Hsp72 in cytoplasm was also higher but not to such extent as that observed in the nucleus. Preincubation of heated cells with quercetin inhibited strong Hsp72 expression observed after hyperthermia and changed the intracellular Hsp72 distribution. The cytoplasmic level of protein exceeded the nuclear one, especially around the nucleus, where the coat of Hsp72 was noticed. Observations indicating that quercetin was present around and in the nuclear envelope suggested an involvement of this drug in the inhibition of nuclear translocation. Our results indicate that pro-apoptotic activity of quercetin may be correlated not only with the inhibition of Hsp72 expression but also with suppression of its migration to the nucleus.

  10. Hsp100/ClpB Chaperone Function and Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Vierling, Elizabeth [Univ. of Massachusetts, Amherst, MA (United States). Dept. of Biochemistry and Molecular Biology

    2015-01-27

    The supported research investigated the mechanism of action of a unique class of molecular chaperones in higher plants, the Hsp100/ClpB proteins, with the ultimate goal of defining how these chaperones influence plant growth, development, stress tolerance and productivity. Molecular chaperones are essential effectors of cellular “protein quality control”, which comprises processes that ensure the proper folding, localization, activation and turnover of proteins. Hsp100/ClpB proteins are required for temperature acclimation in plants, optimal seed yield, and proper chloroplast development. The model plant Arabidopsis thaliana and genetic and molecular approaches were used to investigate two of the three members of the Hsp100/ClpB proteins in plants, cytosolic AtHsp101 and chloroplast-localized AtClpB-p. Investigating the chaperone activity of the Hsp100/ClpB proteins addresses DOE goals in that this activity impacts how “plants generate and assemble components” as well as “allowing for their self repair”. Additionally, Hsp100/ClpB protein function in plants is directly required for optimal “utilization of biological energy” and is involved in “mechanisms that control the architecture of energy transduction systems”.

  11. Characteristics and performance of the Sunna high dose dosemeter using green photoluminescence and UV absorption readout methods

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S.D.; Murphy, M.K.; Tinker, M.R.; Kovacs, A.; McLaughlin, W

    2002-07-01

    Growth in the use of ionising radiation for medical sterilisation and the potential for wide-scale international food irradiation have created the need for robust, mass-producible, inexpensive, and highly accurate radiation dosemeters. The Sunna dosemeter, lithium fluoride injection-moulded in a polyethylene matrix, can be read out using either green photoluminescence or ultraviolet (UV) absorption. The Sunna dosemeter can be mass-produced inexpensively with high precision. Both the photoluminescent and the UV absorption reader are simple and inexpensive. Both methods of analysis display negligible humidity effects, minimal dose rate dependence, acceptable post-irradiation effects, and permit measurements with a precision of nearly 1% 1s. The UV method shows negligible irradiation temperature effects from -30 deg. C to +60 deg. C. The photoluminescence method shows negligible irradiation temperature effects above room temperature for sterilisation dose levels and above. The dosimetry characteristics of these two readout methods are presented along with performance data in commercial sterilisation facilities. (author)

  12. RNAi knockdown of Hop (Hsp70/Hsp90 organising protein) decreases invasion via MMP-2 down regulation.

    LENUS (Irish Health Repository)

    Walsh, Naomi

    2011-07-28

    We previously identified Hop as over expressed in invasive pancreatic cancer cell lines and malignant tissues of pancreatic cancer patients, suggesting an important role for Hop in the biology of invasive pancreatic cancer. Hop is a co-chaperone protein that binds to both Hsp70\\/Hsp90. We hypothesised that by targeting Hop, signalling pathways modulating invasion and client protein stabilisation involving Hsp90-dependent complexes may be altered. In this study, we show that Hop knockdown by small interfering (si)RNA reduces the invasion of pancreatic cancer cells, resulting in decreased expression of the downstream target gene, matrix metalloproteinases-2 (MMP-2). Hop in conditioned media co-immunoprecipitates with MMP-2, implicating a possible extracellular function for Hop. Knockdown of Hop expression also reduced expression levels of Hsp90 client proteins, HER2, Bcr-Abl, c-MET and v-Src. Furthermore, Hop is strongly expressed in high grade PanINs compared to lower PanIN grades, displaying differential localisation in invasive ductal pancreatic cancer, indicating that the localisation of Hop is an important factor in pancreatic tumours. Our data suggests that the attenuation of Hop expression inactivates key signal transduction proteins which may decrease the invasiveness of pancreatic cancer cells possibly through the modulation of Hsp90 activity. Therefore, targeting Hop in pancreatic cancer may constitute a viable strategy for targeted cancer therapy.

  13. Neonatal Death and Heart Failure in Mouse with Transgenic HSP60 Expression

    Directory of Open Access Journals (Sweden)

    Tsung-Hsien Chen

    2015-01-01

    Full Text Available Mitochondrial heat shock proteins, such as HSP60, are chaperones responsible for the folding, transport, and quality control of mitochondrial matrix proteins and are essential for maintaining life. Both prosurvival and proapoptotic roles have been proposed for HSP60, and HSP60 is reportedly involved in the initiation of autoimmune, metabolic, and cardiovascular diseases. The role of HSP60 in pathogenesis of these diseases remains unclear, partly because of the lack of mouse models expressing HSP60. In this study we generated HSP60 conditional transgenic mice suitable for investigating in vivo outcomes by expressing HSP60 at the targeted organ in disease models. Ubiquitous HSP60 induction in the embryonic stage caused neonatal death in mice at postnatal day 1. A high incidence of atrial septal defects was observed in HSP60-expressing mice, with increased apoptosis and myocyte degeneration that possibly contributed to massive hemorrhage and sponge-like cardiac muscles. Our results showed that neonatal heart failure through HSP60 induction likely involves developmental defects and excessive apoptosis. The conditional HSP60 mouse model is useful for studying crucial biological questions concerning HSP60.

  14. Determination of the dose rapidity of a 90 Sr beta radiation source using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Gonzalez M, P.R.; Azorin N, J.; Rivera M, T.

    2000-01-01

    The thermoluminescent dosemeters developed in Mexico, have been used efficiently in environmental and personal dosimetry. When the dose rate of some source is not known can be estimated with the use of thermoluminescent dosemeters taking in account the geometrical array used in the irradiations for reproducibility of the results in posterior irradiations. In this work it was estimated the dose rate of a 90 Sr- 90 Y beta radiation source which is property of the Nuclear Sciences Institute, UNAM, therefore it was l ended to the Metropolitan Autonomous University- Iztapalapa Unit for the characterization of new Tl materials, taking account of the institutional collaboration agreements. (Author)

  15. HDJC9, a novel human type C DnaJ/HSP40 member interacts with and cochaperones HSP70 through the J domain

    International Nuclear Information System (INIS)

    Han Chaofeng; Chen Taoyong; Li Nan; Yang Mingjin; Wan Tao; Cao Xuetao

    2007-01-01

    HSP40s are a subfamily of heat shock proteins (HSPs) and play important roles in regulation of cell proliferation, survival and apoptosis by serving as chaperones for HSP70s. Up to date hundreds of HSP40 proteins derived from various species ranging from Escherichia coli to homo sapiens have been identified. Here we report the cloning and characterization of a novel human type C DnaJ homologue, HDJC9, containing a typical N-terminal J domain. HDJC9 is upregulated at both mRNA and protein levels upon various stress and mitogenic stimulations. HDJC9 is mainly localized in cell nuclei under normal culture conditions while it is transported into cytoplasm and plasma membrane upon heat shock stress through a non-classical and lipid-dependent pathway. HDJC9 can interact with HSP70s and activate the ATPase activity of HSP70s, both of which are dependent on the J domain. Our data suggest that HDJC9 is a novel cochaperone for HSP70s

  16. Characteristics and performances of electronic personal dosemeters

    International Nuclear Information System (INIS)

    Aubert, B.

    2002-01-01

    The regulations have made obligation for 2 years to measure and analyse the amounts of radiations actually received during an operation. The whole of these measurements taken uninterrupted for an immediate reading is indicated like the operational dosimetry, which is carried out with the means of personal electronic dosemeters. This study analyses the legislation relating to this type of dosimetry as well as the requirements in medical environment, and presents an assessment of the characteristics and performances of the devices available on the French market at the beginning of 2002 starting from the information provided by the various manufacturers. (author)

  17. Exploring the Functional Complementation between Grp94 and Hsp90.

    Directory of Open Access Journals (Sweden)

    Kevin A Maharaj

    Full Text Available Grp94 and Hsp90 are the ER and cytoplasmic paralog members, respectively, of the hsp90 family of molecular chaperones. The structural and biochemical differences between Hsp90 and Grp94 that allow each paralog to efficiently chaperone its particular set of clients are poorly understood. The two paralogs exhibit a high degree of sequence similarity, yet also display significant differences in their quaternary conformations and ATPase activity. In order to identify the structural elements that distinguish Grp94 from Hsp90, we characterized the similarities and differences between the two proteins by testing the ability of Hsp90/Grp94 chimeras to functionally substitute for the wild-type chaperones in vivo. We show that the N-terminal domain or the combination of the second lobe of the Middle domain plus the C-terminal domain of Grp94 can functionally substitute for their yeast Hsp90 counterparts but that the equivalent Hsp90 domains cannot functionally replace their counterparts in Grp94. These results also identify the interface between the Middle and C-terminal domains as an important structural unit within the Hsp90 family.

  18. Plant Hsp90 Proteins Interact with B-Cells and Stimulate Their Proliferation

    Science.gov (United States)

    Corigliano, Mariana G.; Maglioco, Andrea; Laguía Becher, Melina; Goldman, Alejandra; Martín, Valentina; Angel, Sergio O.; Clemente, Marina

    2011-01-01

    Background The molecular chaperone heat shock protein 90 (Hsp90) plays an important role in folding stabilization and activation of client proteins. Besides, Hsp90 of mammals and mammalian pathogens displays immunostimulatory properties. Here, we investigated the role of plant-derived Hsp90s as B-cell mitogens by measuring their proliferative responses in vitro. Methodology Plant cytosolic Hsp90 isoforms from Arabidopsis thaliana (AtHsp81.2) and Nicotiana benthamiana (NbHsp90.3) were expressed in E. coli. Over-expression of recombinant plant Hsp90s (rpHsp90s) was confirmed by SDS-PAGE and western blot using and anti-AtHsp81.2 polyclonal anti-body. Both recombinant proteins were purified by Ni-NTA affinity chromatography and their identity confirmed by MALDI-TOF-TOF. Recombinant AtHsp81.2 and NbHsp90.3 proteins induced prominent proliferative responses in spleen cells form BALB/c mice. Polymyxin-B, a potent inhibitor of lipopolysaccharide (LPS), did not eliminate the rpHsp90-induced proliferation. In addition, in vitro incubation of spleen cells with rpHsp90 led to the expansion of CD19-bearing populations, suggesting a direct effect of these proteins on B lymphocytes. This effect was confirmed by immunofluorescence analysis, where a direct binding of rpHsp90 to B- but not to T-cells was observed in cells from BALB/c and C3H/HeN mice. Finally, we examined the involvement of Toll Like Receptor 4 (TLR4) molecules in the rpHsp90s induction of B-cell proliferation. Spleen cells from C3H/HeJ mice, which carry a point mutation in the cytoplasmic region of TLR4, responded poorly to prAtHsp90. However, the interaction between rpHsp90 and B-cells from C3H/HeJ mice was not altered, suggesting that the mutation on TLR4 would be affecting the signal cascade but not the rpHsp90-TLR4 receptor interaction. Conclusions Our results show for the first time that spleen cell proliferation can be stimulated by a non-pathogen-derived Hsp90. Furthermore, our data provide a new example of

  19. Method of making isodose curve using thermoluminescence dosemeter

    International Nuclear Information System (INIS)

    Bakar Ramain, A.

    1975-01-01

    Line source of 60 Co in the form of needles and tubes are extensively used in radiotherapy in moulds, implants, and intracavitary techniques for the treatment of malignant lesions. It is important to have isodose distributions in tissue for those source for purposes of treatment planning. The isodose distributions have been obtained experimentally by using tinny lithium-fluoride (Lsub(i)F) thermoluminescent dosemeters (TLD) and they are compared to the theoretical results. The distinct advantages of Lsub(i)F (TLD) in such measurements are briefly discussed. (author)

  20. New KID dosemeter for measurement of cosmic dosimetry

    International Nuclear Information System (INIS)

    Peksova, D.; Kakona, M.; Krist, P.; Kocur, Z.; Larina, K. V.; Ploc, O.

    2018-01-01

    The KID dosemeter is a small semiconductor low-power detector developed for common use. The current design is special designed after measuring cosmic rays on aircraft decks. The design concept is the same world-class devices Internet of Things (IoT). As a detection element detector were tested three variants a) PIN HAMAMATSU S2744-09 photodiode, b) 9 parallel Vishay photodiodes TEMD5080X01, c) 16 Vishay photodiode TEMD5080X01 again in parallel connection. All variants are silicon PIN photodiode. (authors)

  1. Evaluation of influence by room-scattered neutrons and source-to-phantom geometrical effect for calibration of personal neutron dosemeters

    International Nuclear Information System (INIS)

    Yoshida, Tadayoshi; Tsujimura, Norio

    2005-01-01

    Correction for the influence of room-scattered neutrons in irradiation rooms is essential in the case of calibrating neutron dosemeters. The ISO8529-2 recommends some correction method such as the shadow-cone method and the generalized-fit method for the calibration of neutron ambient dose equivalent (rate) meters. However, the ISO standard does not describe the correction methods for personal neutron dosemeters in detail. The authors investigated the variation of responses of neutron detectors mounted on phantom as a function of source-to-phantom distance, and discussed the applicability of the shadow-cone method and generalized-fit method for calibrating personal neutron dosemeters. The measurements were carried out using 3 He and hydrogen-filled proportional counters as surrogates of albedo and recoil-proton type dosemeters, respectively, at different distances ranging from 30 cm to 400 cm. As a result, it was clarified that both correction methods are applicable for recoil-proton type detectors over any distance. Contrarily, for albedo-type detectors, the variation of response does not follow the curve predicted from the generalized fit method at distances smaller than 70 cm. This result strongly suggests that the correction for source-to-phantom geometry effect should be made for calibrating albedo-type detectors at smaller distances. (author)

  2. Hsp90 selectively modulates phenotype in vertebrate development.

    Directory of Open Access Journals (Sweden)

    Patricia L Yeyati

    2007-03-01

    Full Text Available Compromised heat shock protein 90 (Hsp90 function reveals cryptic phenotypes in flies and plants. These observations were interpreted to suggest that this molecular stress-response chaperone has a capacity to buffer underlying genetic variation. Conversely, the protective role of Hsp90 could account for the variable penetrance or severity of some heritable developmental malformations in vertebrates. Using zebrafish as a model, we defined Hsp90 inhibitor levels that did not induce a heat shock response or perturb phenotype in wild-type strains. Under these conditions the severity of the recessive eye phenotype in sunrise, caused by a pax6b mutation, was increased, while in dreumes, caused by a sufu mutation, it was decreased. In another strain, a previously unobserved spectrum of severe structural eye malformations, reminiscent of anophthalmia, microphthalmia, and nanophthalmia complex in humans, was uncovered by this limited inhibition of Hsp90 function. Inbreeding of offspring from selected unaffected carrier parents led to significantly elevated malformation frequencies and revealed the oligogenic nature of this phenotype. Unlike in Drosophila, Hsp90 inhibition can decrease developmental stability in zebrafish, as indicated by increased asymmetric presentation of anophthalmia, microphthalmia, and nanophthalmia and sunrise phenotypes. Analysis of the sunrise pax6b mutation suggests a molecular mechanism for the buffering of mutations by Hsp90. The zebrafish studies imply that mild perturbation of Hsp90 function at critical developmental stages may underpin the variable penetrance and expressivity of many developmental anomalies where the interaction between genotype and environment plays a major role.

  3. Selection Transforms the Landscape of Genetic Variation Interacting with Hsp90.

    Science.gov (United States)

    Geiler-Samerotte, Kerry A; Zhu, Yuan O; Goulet, Benjamin E; Hall, David W; Siegal, Mark L

    2016-10-01

    The protein-folding chaperone Hsp90 has been proposed to buffer the phenotypic effects of mutations. The potential for Hsp90 and other putative buffers to increase robustness to mutation has had major impact on disease models, quantitative genetics, and evolutionary theory. But Hsp90 sometimes contradicts expectations for a buffer by potentiating rapid phenotypic changes that would otherwise not occur. Here, we quantify Hsp90's ability to buffer or potentiate (i.e., diminish or enhance) the effects of genetic variation on single-cell morphological features in budding yeast. We corroborate reports that Hsp90 tends to buffer the effects of standing genetic variation in natural populations. However, we demonstrate that Hsp90 tends to have the opposite effect on genetic variation that has experienced reduced selection pressure. Specifically, Hsp90 tends to enhance, rather than diminish, the effects of spontaneous mutations and recombinations. This result implies that Hsp90 does not make phenotypes more robust to the effects of genetic perturbation. Instead, natural selection preferentially allows buffered alleles to persist and thereby creates the false impression that Hsp90 confers greater robustness.

  4. Spatio-temporal regulation of Hsp90-ligand complex leads to immune activation.

    Directory of Open Access Journals (Sweden)

    Yasuaki eTamura

    2016-05-01

    Full Text Available Hsp90 is the most abundant cytosolic HSP and is known to act as a molecular chaperone. We found that an Hsp90-cancer antigen peptide complex was efficiently cross-presented by human monocyte-derived dendritic cells and induced peptide-specific cytotoxic T lymphocytes. Furthermore, we observed that the internalized Hsp90-peptide complex was strictly sorted to the Rab5+, EEA1+ static early endosome and the Hsp90-chaperoned peptide was processed and bound to MHC class I molecules through a endosome-recycling pathway. We also found that extracellular Hsp90 complexed with CpG-A or self-DNA stimulates production of a large amount of IFN-α from pDCs via static early endosome targeting. Thus, extracellular Hsp90 can target the antigen or nucleic acid to a static early endosome by spatio-temporal regulation. Moreover, we showed that Hsp90 associates with and delivers TLR7/9 from the ER to early endosomes for ligand recognition. Hsp90 inhibitor, geldanamycin derivative inhibited the Hsp90 association with TLR7/9, resulting in inhibition IFN-α production, leading to improvement of SLE symptoms. Interstingly, we observed that serum Hsp90 is clearly increased in patients with active SLE compared with that in patients with inactive disease. Serum Hsp90 detected in SLE patients binds to self-DNA and/or anti-DNA Ab, thus leading to stimulation of pDCs to produce IFN-α. Thus, Hsp90 plays a crucial role in the pathogenesis of SLE and that an Hsp90 inhibitor will therefore provide a new therapeutic approach to SLE and other nucleic acid-related autoimmune diseases. We will discuss how spatio-temporal regulation of Hsp90-ligand complexes within antigen-presenting cells affects the innate immunity and adaptive immunity.

  5. Hsp90 Is Essential under Heat Stress in the Bacterium Shewanella oneidensis

    Directory of Open Access Journals (Sweden)

    Flora Ambre Honoré

    2017-04-01

    Full Text Available The Hsp90 chaperone is essential in eukaryotes and activates a large array of client proteins. In contrast, its role is still elusive in bacteria, and only a few Hsp90 bacterial clients are known. Here, we found that Hsp90 is essential in the model bacterium Shewanella oneidensis under heat stress. A genetic screen for Hsp90 client proteins identified TilS, an essential protein involved in tRNA maturation. Overexpression of TilS rescued the growth defect of the hsp90 deletion strain under heat stress. In vivo, the activity and the amount of TilS were significantly reduced in the absence of Hsp90 at high temperature. Furthermore, we showed that Hsp90 interacts with TilS, and Hsp90 prevents TilS aggregation in vitro at high temperature. Together, our results indicate that TilS is a client of Hsp90 in S. oneidensis. Therefore, our study links the essentiality of bacterial Hsp90 at high temperature with the identification of a client.

  6. Hsp70-Bag3 interactions regulate cancer-related signaling networks.

    Science.gov (United States)

    Colvin, Teresa A; Gabai, Vladimir L; Gong, Jianlin; Calderwood, Stuart K; Li, Hu; Gummuluru, Suryaram; Matchuk, Olga N; Smirnova, Svetlana G; Orlova, Nina V; Zamulaeva, Irina A; Garcia-Marcos, Mikel; Li, Xiaokai; Young, Z T; Rauch, Jennifer N; Gestwicki, Jason E; Takayama, Shinichi; Sherman, Michael Y

    2014-09-01

    Bag3, a nucleotide exchange factor of the heat shock protein Hsp70, has been implicated in cell signaling. Here, we report that Bag3 interacts with the SH3 domain of Src, thereby mediating the effects of Hsp70 on Src signaling. Using several complementary approaches, we established that the Hsp70-Bag3 module is a broad-acting regulator of cancer cell signaling by modulating the activity of the transcription factors NF-κB, FoxM1, Hif1α, the translation regulator HuR, and the cell-cycle regulators p21 and survivin. We also identified a small-molecule inhibitor, YM-1, that disrupts the Hsp70-Bag3 interaction. YM-1 mirrored the effects of Hsp70 depletion on these signaling pathways, and in vivo administration of this drug was sufficient to suppress tumor growth in mice. Overall, our results defined Bag3 as a critical factor in Hsp70-modulated signaling and offered a preclinical proof-of-concept that the Hsp70-Bag3 complex may offer an appealing anticancer target. ©2014 American Association for Cancer Research.

  7. Decreased Hsp90 expression in infiltrative lobular carcinoma: an immunohistochemical study

    International Nuclear Information System (INIS)

    Zagouri, Flora; Patsouris, Effstratios; Zografos, George; Sergentanis, Theodoros; Nonni, Afrodite; Papadimitriou, Christos; Pazaiti, Anastasia; Michalopoulos, Nikolaos V; Safioleas, Panagiotis; Lazaris, Andreas; Theodoropoulos, George

    2010-01-01

    Elevated Hsp90 expression has been documented in breast ductal carcinomas, whereas decreased Hsp90 expression has been reported in precursor lobular lesions. This study aims to assess Hsp90 expression in infiltrative lobular carcinomas of the breast. Tissue specimens were taken from 32 patients with infiltrative lobular carcinoma. Immunohistochemical assessment of Hsp90 was performed both in the lesion and the adjacent normal breast ducts and lobules; the latter serving as control. Concerning Hsp90 assessment: i) the percentage of positive cells and ii) the intensity were separately analyzed. Subsequently, the Allred score was adopted and calculated. The intensity was treated as an ordinal variable-score (0: negative, low: 1, moderate: 2, high: 3). Statistical analysis followed. All infiltrative lobular carcinoma foci mainly presented with a positive cytoplasmic immunoreaction for Hsp90. Compared to the adjacent normal ducts and lobules, infiltrative lobular carcinoma exhibited a statistically significant decrease in Hsp90 expression, both in terms of Hsp90 positive cells (%) and Allred score (74.2 ± 11.2 vs. 59.1 ± 14.2 p = 0.0001; 7.00 ± 0.95 vs. 6.22 ± 1.01, p = 0.007, Wilcoxon matched-pairs signed-ranks test). Concerning the intensity of Hsp90 immunostaining only a marginal decrease was noted (2.16 ± 0.68 vs. 1.84 ± 0.63, p = 0.087, Wilcoxon matched-pairs signed-ranks test). ILC lesions seem to exhibit decreased Hsp90 expression, a finding contrary to what might have been expected, given that high Hsp90 expression is a trait of invasive ductal carcinomas

  8. A novel biomarker for marine environmental pollution of HSP90 from Mytilus coruscus

    International Nuclear Information System (INIS)

    Liu, Huihui; Wu, Jiong; Xu, Mengshan; He, Jianyu

    2016-01-01

    Heat shock protein 90 (HSP90) is a conserved molecular chaperone contributing to cell cycle control, organism development and the proper regulation of cytosolic proteins. The full-length HSP90 cDNA of Mytilus coruscus (McHSP90, KT946644) was 2420 bp, including an ORF of 2169 bp encoding a polypeptide of 722 amino acids with predicted pI/MW 4.89/83.22 kDa. BLASTp analysis and phylogenetic relationship strongly suggested McHSP90 was a member of HSP90 family, and it was highly conserved with other known HSP90, especially in the HSP90 family signatures, ATP/GTP-Binding sites and ‘EEVD’ motif. The mRNA of McHSP90 in haemolymph was upregulated in all treatments including Vibrio alginolyticus and Vibrio harveyi challenge, metals stresses (copper and cadmium) and 180 CST fuel exposure. All the results implied the expression of McHSP90 could be affected by Vibrio challenge and environmental stress, which might help us gain more insight into the molecular mechanism of HSP against adverse stresses in mollusca. - Highlights: • A novel HSP90 (McHSP90) was identified from Mytilus coruscus. • McHSP90 significantly affected by Vibrio challenge for immune defense. • McHSP90 mRNA was obviously up-regulated under stress of heavy metals and 180CST fuel. • McHSP90 might be an ideal marine pollution indicator.

  9. Aluminium nitrate ceramics: A potential UV dosemeter material

    DEFF Research Database (Denmark)

    Trinkler, L.; Bøtter-Jensen, L.; Berzina, B.

    2002-01-01

    The ceramic material AIN-Y2O3 is proposed as a potential ultraviolet radiation (UVR) dosemeter using optically stimulated luminescence (OSL) and thermally stimulated luminescence (TL). Experimental studies have shown that AIN ceramics exhibit attractive characteristics suitable for practical UV...... dosimetry applications. The features are: (1) the spectral sensitivity covers the 200-350 nm range, in the UV-B region it is similar to that of human skin: (2) the angular dependence of the incident radiation follows the cosine law; (3) high yields of both UVR-induced OSL and TL signals compared to those...

  10. Results of the IAEA/RCA personal dosemeter intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    Tsujimura, Norio; Momose, Takumaro; Hayashi, Naomi [Environment and Safety Division, Tokai Works, Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

    2000-06-01

    The intercomparison of personal dosemeters for photon was carried out between 1990 and 1996 as part of the IAEA/RCA 'strengthening of radiation protection infrastructure' project. Japan Nuclear Cycle Development Institute participated in the intercomparison as one of the in-house personal dosimetry service organizations in Japan and also served the host irradiating laboratory. This report summarizes the dose evaluation results obtained from the JNC-TLD badges in the past four intercomparison programs. In the latest intercomparison the evaluated doses agreed to the reference doses with an accuracy of 10%. (author)

  11. The Hsp60C gene in the 25F cytogenetic region in Drosophila ...

    Indian Academy of Sciences (India)

    Unknown

    Earlier studies have shown that of the four genes (Hsp60A, Hsp60B, Hsp60C, Hsp60D genes) predicted to encode the conserved Hsp60 family chaperones in Drosophila melanogaster, the ..... C. Genomic organization and the predicted.

  12. Genome-wide analysis of the Hsp70 family genes in pepper (Capsicum annuum L.) and functional identification of CaHsp70-2 involvement in heat stress.

    Science.gov (United States)

    Guo, Meng; Liu, Jin-Hong; Ma, Xiao; Zhai, Yu-Fei; Gong, Zhen-Hui; Lu, Ming-Hui

    2016-11-01

    Hsp70s function as molecular chaperones and are encoded by a multi-gene family whose members play a crucial role in plant response to stress conditions, and in plant growth and development. Pepper (Capsicum annuum L.) is an important vegetable crop whose genome has been sequenced. Nonetheless, no overall analysis of the Hsp70 gene family is reported in this crop plant to date. To assess the functionality of Capsicum annuum Hsp70 (CaHsp70) genes, pepper genome database was analyzed in this research. A total of 21 CaHsp70 genes were identified and their characteristics were also described. The promoter and transcript expression analysis revealed that CaHsp70s were involved in pepper growth and development, and heat stress response. Ectopic expression of a cytosolic gene, CaHsp70-2, regulated expression of stress-related genes and conferred increased thermotolerance in transgenic Arabidopsis. Taken together, our results provide the basis for further studied to dissect CaHsp70s' function in response to heat stress as well as other environmental stresses. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Dose profile measurement in computerized axial tomography equipment using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Azorin V, J.C.; Falcony, C.; Azorin N, J.

    2000-01-01

    In this work are presented the results about measuring the radiation dose profile in two equipment of computerized axial tomography (Tac). Thermoluminescent dosemeters (Dtl) of LiF, Mg, Cu, P + Ptfe in form of disks were used which were developed and made in Mexico. The results showed that Dtl are appropriated for these type of studies. (Author)

  14. Protective Role of Hsp27 Protein Against Gamma Radiation-Induced Apoptosis and Radiosensitization Effects of Hsp27 Gene Silencing in Different Human Tumor Cells

    International Nuclear Information System (INIS)

    Aloy, Marie-Therese; Hadchity, Elie; Bionda, Clara; Diaz-Latoud, Chantal; Claude, Line; Rousson, Robert; Arrigo, Andre-Patrick; Rodriguez-Lafrasse, Claire

    2008-01-01

    Purpose: The ability of heat shock protein 27 (Hsp27) to protect cells from stressful stimuli and its increased levels in tumors resistant to anticancer therapeutics suggest that it may represent a target for sensitization to radiotherapy. In this study, we investigate the protective role of Hsp27 against radiation-induced apoptosis and the effect of its attenuation in highly expressing radioresistant cancer cell lines. Methods and Materials: We examined clonogenic death and the kinetics of apoptotic events in different tumor cell lines overexpressing or underexpressing Hsp27 protein irradiated with photons. The radiosensitive Jurkat cell line, which does not express Hsp27 constitutively or in response to γ-rays, was stably transfected with Hsp27 complementary DNA. Attenuation of Hsp27 expression was accomplished by antisense or RNAi (interfering RNA) strategies in SQ20B head-and-neck squamous carcinoma, PC3 prostate cancer, and U87 glioblastoma radioresistant cells. Results: We measured concentration-dependent protection against the cytotoxic effects of radiation in Jurkat-Hsp27 cells, which led to a 50% decrease in apoptotic cells at 48 hours in the highest expressing cells. Underlying mechanisms leading to radiation resistance involved a significant increase in glutathione levels associated with detoxification of reactive oxygen species, a delay in mitochondrial collapse, and caspase activation. Conversely, attenuation of Hsp27 in SQ20B cells, characterized by their resistance to apoptosis, sensitizes cells to irradiation. This was emphasized by increased apoptosis, decreased glutathione basal level, and clonogenic cell death. Sensitization to irradiation was confirmed in PC3 and U87 radioresistant cells. Conclusion: Hsp27 gene therapy offers a potential adjuvant to radiation-based therapy of resistant tumors

  15. Sequential folding of UmuC by the Hsp70 and Hsp60 chaperone complexes of Escherichia coli.

    Science.gov (United States)

    Petit, M A; Bedale, W; Osipiuk, J; Lu, C; Rajagopalan, M; McInerney, P; Goodman, M F; Echols, H

    1994-09-23

    Replication-blocking lesions generate a signal in Escherichia coli that leads to the induction of the multigene SOS response. Among the SOS-induced genes are umuD and umuC, whose products are necessary for the increased mutation rate in induced bacteria. The mutations are likely to result from replication across the DNA lesion, and such a bypass event has been reconstituted in vitro (Rajagopalan, M., L, C., Woodgate, R., O'Donnel, M., Goodman, M. F., Echols, H. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 10777-10781). In this work, we show that the chaperone proteins promote the proper folding of UmuC protein in vitro. We treated purified and inactive UmuC with Hsp70 and Hsp60. After Hsp70 treatment, the DNA binding activity of UmuC was recovered, but the ability to promote replication across DNA lesions was not. However, lesion bypass activity was recovered upon further treatment with Hsp60. The biological significance of such a folding pathway for UmuC protein is strengthened by in vivo evidence for a role of DnaK in UV-induced mutagenesis.

  16. Operational comparison of TLD albedo dosemeters and etched-track detectors in the PuO2-UO2 mixed oxide fuel fabrication facilities

    International Nuclear Information System (INIS)

    Tsujimura, N.; Takada, C.; Yoshida, T.; Momose, T.

    2005-01-01

    Full text: The authors carried out an operational study that compared the use of TLD albedo dosemeters with etched-track detector in plutonium environments of Japan Nuclear Cycle Development Institute, Tokai Works. A selected group of workers engaged in the fabrication process of MOX (PuO 2 -UO 2 mixed oxide) fuel wore both TLD albedo dosemeters and etched-track detectors over a period from 1991 to 1993. The TLD albedo dosemeter is the Panasonic model UD-809P and the etched-track detector is the NEUTRAK (polyallyl diglycol carbonate + 1mm-t polyethylene radiator) commercially available from Nagase-Landauer Ltd. Both dosemeters were issued and read monthly. It was found that the TL readings were generally proportional to the counted etch-pits, and thus the dose equivalent results obtained from TLD albedo dosemeter agreed with those from etched-track detector within a factor of 1.5. This result indicates that, in the workplaces of the MOX plants, the neutron spectrum remained almost constant in terms of time and space, and the appropriate range of field-specific correction with spectrum variations could be small in albedo dosimetry. In addition, the calibrations of both dosemeters in the workplaces and in a bare and moderated 252 Cf calibration field were performed for quantitative validation for the results from the operational comparison. In the former experiments, locations were selected that were representative of typical neutron measurements according to the prior neutron spectra measurements with the multi-sphere spectrometer. In the latter experiments, the workplace environments were simulated by using a 252 Cf source surrounded with cylindrical steel/PMMA moderators. From both experiments, the relationship between TL readings and counted etch-pits with neutron spectrum variation was determined. As expected, the relationship obtained from the simulated workplace field calibration reproduced that from the operational comparison. (author)

  17. Decreased Hsp90 expression in infiltrative lobular carcinoma: an immunohistochemical study

    Directory of Open Access Journals (Sweden)

    Zagouri Flora

    2010-08-01

    Full Text Available Abstract Background Elevated Hsp90 expression has been documented in breast ductal carcinomas, whereas decreased Hsp90 expression has been reported in precursor lobular lesions. This study aims to assess Hsp90 expression in infiltrative lobular carcinomas of the breast. Methods Tissue specimens were taken from 32 patients with infiltrative lobular carcinoma. Immunohistochemical assessment of Hsp90 was performed both in the lesion and the adjacent normal breast ducts and lobules; the latter serving as control. Concerning Hsp90 assessment: i the percentage of positive cells and ii the intensity were separately analyzed. Subsequently, the Allred score was adopted and calculated. The intensity was treated as an ordinal variable-score (0: negative, low: 1, moderate: 2, high: 3. Statistical analysis followed. Results All infiltrative lobular carcinoma foci mainly presented with a positive cytoplasmic immunoreaction for Hsp90. Compared to the adjacent normal ducts and lobules, infiltrative lobular carcinoma exhibited a statistically significant decrease in Hsp90 expression, both in terms of Hsp90 positive cells (% and Allred score (74.2 ± 11.2 vs. 59.1 ± 14.2 p = 0.0001; 7.00 ± 0.95 vs. 6.22 ± 1.01, p = 0.007, Wilcoxon matched-pairs signed-ranks test. Concerning the intensity of Hsp90 immunostaining only a marginal decrease was noted (2.16 ± 0.68 vs. 1.84 ± 0.63, p = 0.087, Wilcoxon matched-pairs signed-ranks test. Conclusion ILC lesions seem to exhibit decreased Hsp90 expression, a finding contrary to what might have been expected, given that high Hsp90 expression is a trait of invasive ductal carcinomas.

  18. Thermoluminescent response of dosemeters TLD-100 exposed to distinct baker protocols, irradiation and reading

    International Nuclear Information System (INIS)

    Estrada E, D.

    2002-01-01

    The interest that motivated the realization of this work is the opposing discrepancy among the values of the efficiency thermoluminescent of heavy charged particles (PCP) regarding gamma radiation (η PCP , γ) reported in different works and gathered recently for Horowitz (Ho 01). The measures of relative thermoluminescent efficiency have importance in relation to the dosimetry associated to medical therapy with heavy charged particle. The measurement of η PCP , γ depends of multiple experimental factors. To understand this dependence it was quantified the effect of using different procedures experimental in the estimate of the relative thermoluminescent efficiency of dosemeters TLD-100 (LiF: Ti; Mg) for protons of 3 MeV regarding gamma rays of 60 Co (η PCP , γ), varying the lot, the presentation, the one baked and the team reader. When was used the same global procedure values they were obtained for (η PCP , γ) inside the interval [0.30, 0.58] for the peak 5 and [0.35, 0.76] for the total thermoluminescent signal (Tl). At the use different equipment, baked and lot are obtained maximum differences of 30%, 12% and 6% respectively in the values of (η PCP , γ) for the peak 5, and 25%, 28% and 7% for the total Tl signal. The changes more significant of 36% and 44% for peak 5 and total signal respectively are obtained when changing the presentation of the dosemeter. As a complementary investigation it was studied the distribution of the Tl signal of each peak in the deconvolution of the curve of brightness with regard to the total signal in exposed dosemeters to high fluence of protons (1x10 10 p/cm 2 ) varying the experimental protocol. It was found that the distribution of the Tl signal has a difference of the order of 5% when changing the used reading team. It was observed that the contribution of the peak 5 regarding the total signal are preserved when changing baked and that it results to be 8% greater for the presentation in dosemeters of 1 x 1 x 1 mm 3

  19. Stability of the Human Hsp90-p50Cdc37 Chaperone Complex against Nucleotides and Hsp90 Inhibitors, and the Influence of Phosphorylation by Casein Kinase 2

    Directory of Open Access Journals (Sweden)

    Sanne H. Olesen

    2015-01-01

    Full Text Available The molecular chaperone Hsp90 is regulated by co-chaperones such as p50Cdc37, which recruits a wide selection of client protein kinases. Targeted disruption of the Hsp90-p50Cdc37 complex by protein–protein interaction (PPI inhibitors has emerged as an alternative strategy to treat diseases characterized by aberrant Hsp90 activity. Using isothermal microcalorimetry, ELISA and GST-pull down assays we evaluated reported Hsp90 inhibitors and nucleotides for their ability to inhibit formation of the human Hsp90β-p50Cdc37 complex, reconstituted in vitro from full-length proteins. Hsp90 inhibitors, including the proposed PPI inhibitors gedunin and H2-gamendazole, did not affect the interaction of Hsp90 with p50Cdc37 in vitro. Phosphorylation of Hsp90 and p50Cdc37 by casein kinase 2 (CK2 did not alter the thermodynamic signature of complex formation. However, the phosphorylated complex was vulnerable to disruption by ADP (IC50 = 32 µM, while ATP, AMPPNP and Hsp90 inhibitors remained largely ineffective. The differential inhibitory activity of ADP suggests that phosphorylation by CK2 primes the complex for dissociation in response to a drop in ATP/ADP levels. The approach applied herein provides robust assays for a comprehensive biochemical evaluation of potential effectors of the Hsp90-p50Cdc37 complex, such as phosphorylation by a kinase or the interaction with small molecule ligands.

  20. Proteomics shows Hsp70 does not bind peptide sequences indiscriminately in vivo

    International Nuclear Information System (INIS)

    Grossmann, Michael E.; Madden, Benjamin J.; Gao, Fan; Pang, Yuan-Ping; Carpenter, John E.; McCormick, Daniel; Young, Charles Y.F.

    2004-01-01

    Heat shock protein 70 (Hsp70) binds peptide and has several functions that include protein folding, protein trafficking, and involvement with immune function. However, endogenous Hsp70-binding peptides had not previously been identified. Therefore, we eluted and identified several hundred endogenously bound peptides from Hsp70 using liquid chromatography ion trap mass spectrophotometry (LC-ITMS). Our work shows that the peptides are capable of binding Hsp70 as previously described. They are generally 8-26 amino acids in length and correspond to specific regions of many proteins. Through computationally assisted analysis of peptides eluted from Hsp70 we determined variable amino acid sequences, including a 5 amino acid core sequence that Hsp70 favorably binds. We also developed a computer algorithm that predicts Hsp70 binding within proteins. This work helps to define what peptides are bound by Hsp70 in vivo and suggests that Hsp70 facilitates peptide selection by aiding a funneling mechanism that is flexible but allows only a limited number of peptides to be processed

  1. The MCNP-4C2 design of a two element photon/electron dosemeter that uses magnesium/copper/phosphorus doped lithium fluoride.

    Science.gov (United States)

    Eakins, J S; Bartlett, D T; Hager, L G; Molinos-Solsona, C; Tanner, R J

    2008-01-01

    The Health Protection Agency is changing from using detectors made from 7LiF:Mg,Ti in its photon/electron personal dosemeters, to 7LiF:Mg,Cu,P. Specifically, the Harshaw TLD-700H card is to be adopted. As a consequence of this change, the dosemeter holder is also being modified not only to accommodate the shape of the new card, but also to optimize the photon and electron response characteristics of the device. This redesign process was achieved using MCNP-4C2 and the kerma approximation, electron range/energy tables with additional electron transport calculations, and experimental validation, with different potential filters compared; the optimum filter studied was a polytetrafluoroethylene disc of diameter 18 mm and thickness 4.3 mm. Calculated relative response characteristics at different angles of incidence and energies between 16 and 6174 keV are presented for this new dosemeter configuration and compared with measured type-test results. A new estimate for the energy-dependent relative light conversion efficiency appropriate to the 7LiF:Mg,Cu,P was also derived for determining the correct dosemeter response.

  2. Tumor imaging and targeting potential of an Hsp70-derived 14-mer peptide.

    Directory of Open Access Journals (Sweden)

    Mathias Gehrmann

    Full Text Available We have previously used a unique mouse monoclonal antibody cmHsp70.1 to demonstrate the selective presence of a membrane-bound form of Hsp70 (memHsp70 on a variety of leukemia cells and on single cell suspensions derived from solid tumors of different entities, but not on non-transformed cells or cells from corresponding 'healthy' tissue. This antibody can be used to image tumors in vivo and target them for antibody-dependent cellular cytotoxicity. Tumor-specific expression of memHsp70 therefore has the potential to be exploited for theranostic purposes. Given the advantages of peptides as imaging and targeting agents, this study assessed whether a 14-mer tumor penetrating peptide (TPP; TKDNNLLGRFELSG, the sequence of which is derived from the oligomerization domain of Hsp70 which is expressed on the cell surface of tumor cells, can also be used for targeting membrane Hsp70 positive (memHsp70+ tumor cells, in vitro.The specificity of carboxy-fluorescein (CF- labeled TPP (TPP to Hsp70 was proven in an Hsp70 knockout mammary tumor cell system. TPP specifically binds to different memHsp70+ mouse and human tumor cell lines and is rapidly taken up via endosomes. Two to four-fold higher levels of CF-labeled TPP were detected in MCF7 (82% memHsp70+ and MDA-MB-231 (75% memHsp70+ cells compared to T47D cells (29% memHsp70+ that exhibit a lower Hsp70 membrane positivity. After 90 min incubation, TPP co-localized with mitochondrial membranes in memHsp70+ tumors. Although there was no evidence that any given vesicle population was specifically localized, fluorophore-labeled cmHsp70.1 antibody and TPP preferentially accumulated in the proximity of the adherent surface of cultured cells. These findings suggest a potential association between membrane Hsp70 expression and cytoskeletal elements that are involved in adherence, the establishment of intercellular synapses and/or membrane reorganization.This study demonstrates the specific binding and rapid

  3. Effects of Thermal Stress on the mRNA Expression of SOD, HSP90, and HSP70 in the Spotted Sea Bass ( Lateolabrax maculatus)

    Science.gov (United States)

    Shin, Moon-Kyeong; Park, Ho-Ra; Yeo, Won-Jun; Han, Kyung-Nam

    2018-03-01

    The aim of this study was to elucidate the molecular mechanisms underlying the thermal stress response in the spotted sea bass ( Lateolabrax maculatus). Spotted sea basses were exposed to 4 different water temperatures (20, 22, 24, and 28°C) in increasing increments of 2°C/h from 18°C (control) for different time periods (0, 6, 12, 24, 48, 72, and 96 h). Subsequently, 3 tissues (liver, muscle, and gill) were isolated, and the levels of SOD, HSP90, and HSP70 mRNA were assessed. SOD mRNA expression was maintained at baseline levels of control fish at all water temperatures in the liver, while muscle and gill tissue showed an increase followed by a decrease over each certain time with higher water temperature. HSP90 mRNA expression increased in the liver at ≤ 24°C over time, but maintained baseline expression at 28°C. In muscle, HSP90 mRNA expression gradually increased at all water temperatures, but increased and then decreased at ≥ 24°C in gill tissue. HSP70 mRNA expression exhibited an increase and then a decrease in liver tissue at 28°C, but mainly showed similar expression patterns to HSP90 in all tissues. These results suggest the activity of a defense mechanism using SOD, HSP90, and HSP70 in the spotted sea bass upon rapid increases in water temperature, where the expression of these genes indicated differences between tissues in the extent of the defense mechanisms. Also, these results indicate that high water temperature and long-term thermal stress exposure can inhibit physiological defense mechanisms.

  4. Test of ring, eye lens and whole body dosemeters for the dose quantity Hp(3) to be used in interventional radiology

    Science.gov (United States)

    Szumska, A.; Budzanowski, M.; Kopeć, R.

    2017-11-01

    In its statement on tissue reactions approved on 21st April 2011, the International Commission on Radiological Protection (ICRP, 2012) reviewed its recommendation concerning the equivalent dose limit for the eye lens and reduced the dose limits for occupationally exposed persons to 20 mSv in a year, averaged over defined periods of 5 years, with no single year exceeding 50 mSv. This limit was approved and written down in the new EURATOM (European Atomic Energy Community) directive 2013/59 and in the IAEA (International Atomic Energy Agency) BSS (Basic Safety Standard) of July 2014. For that reason, the necessity to monitor the eye lens may become more important than it was before. However, specially dedicated dosemeters for the dose quantity Hp(3) are using very rarely. Commonly use are only whole body personal dosemeters for the personal dose equivalent quantities Hp(10) worn on the trunk and ring dosemeters worn on finger to measure the quantity Hp(0.07). Therefore, in this work it was investigated whether dosemeters from routine use calibrated in terms of Hp(10) and Hp(0.07) and worn on thyroid collar and protective apron could deliver similar results like dedicated eye lens dosemeter worn close to the eyes. The results show that the best method if dedicated eye lens dosimeters is not used is to measure doses in terms of Hp(0.07) on the thyroid collar (Pearson product, r=0.85). Obtained results shows also importance of proper localization of eye lens dosimeter (close to the eye, from side of the X-ray source).

  5. Regulation of Hsp27 and Hsp70 expression in human and mouse skin construct models by caveolae following exposure to the model sulfur mustard vesicant, 2-chloroethyl ethyl sulfide

    International Nuclear Information System (INIS)

    Black, Adrienne T.; Hayden, Patrick J.; Casillas, Robert P.; Heck, Diane E.; Gerecke, Donald R.; Sinko, Patrick J.; Laskin, Debra L.; Laskin, Jeffrey D.

    2011-01-01

    Dermal exposure to the vesicant sulfur mustard causes marked inflammation and tissue damage. Basal keratinocytes appear to be a major target of sulfur mustard. In the present studies, mechanisms mediating skin toxicity were examined using a mouse skin construct model and a full-thickness human skin equivalent (EpiDerm-FT TM ). In both systems, administration of the model sulfur mustard vesicant, 2-chloroethyl ethyl sulfide (CEES, 100-1000 μM) at the air surface induced mRNA and protein expression of heat shock proteins 27 and 70 (Hsp27 and Hsp70). CEES treatment also resulted in increased expression of caveolin-1, the major structural component of caveolae. Immunohistochemistry revealed that Hsp27, Hsp70 and caveolin-1 were localized in basal and suprabasal layers of the epidermis. Caveolin-1 was also detected in fibroblasts in the dermal component of the full thickness human skin equivalent. Western blot analysis of caveolar membrane fractions isolated by sucrose density centrifugation demonstrated that Hsp27 and Hsp70 were localized in caveolae. Treatment of mouse keratinocytes with filipin III or methyl-β-cyclodextrin, which disrupt caveolar structure, markedly suppressed CEES-induced Hsp27 and Hsp70 mRNA and protein expression. CEES treatment is known to activate JNK and p38 MAP kinases; in mouse keratinocytes, inhibition of these enzymes suppressed CEES-induced expression of Hsp27 and Hsp70. These data suggest that MAP kinases regulate Hsp 27 and Hsp70; moreover, caveolae-mediated regulation of heat shock protein expression may be important in the pathophysiology of vesicant-induced skin toxicity.

  6. Measuring radiation exposure during percutaneous drainages: can shoulder dosemeters be used to estimate finger doses?

    International Nuclear Information System (INIS)

    Vehmas, Tapio; Tikkanen, Heikki

    1992-01-01

    To assess the need for extra finger dosemeters, radiologists' and assistants' radiation exposure at both shoulders and at the third fingers of both hands were recorded using thermoluminescent dosemeters during 27 interventional drainage procedures. Under couch screening was used. Mean dose rates were calculated by dividing dose by screening time. The radiologists' bilateral finger dose rates did not correlate with each other; nor did dose rates between the left shoulder and the right hand. The radiologists' dose rates at both shoulders, correlated with each other, as did shoulder dose rates with dose rates at the ispilateral hand. The right shoulder dose rates correlated with the left hand dose rates. The assistants' dose rates at places of measurement showed significant correlations with each other. (Author)

  7. Calibration of personal dosemeters for extremities of fields of radiation gamma

    International Nuclear Information System (INIS)

    Papadopulos, S.; Gregori, S.; Moreno, B.; Guillen, J.

    1998-01-01

    In this work the conversion factors are presented obtained experimentally of kerma in free air in equivalent dose H(d,O o ) in finger and in arm for fields of radiation gamma of normal incidence dosemeters of extremities was irradiated, based on detecting TL of LIF 7 (TLD-700, Harshaw), placed on the surface of the finger phantom and arm

  8. The role of HSP70 in mediating age-dependent mortality in sepsis

    Science.gov (United States)

    McConnell, Kevin W.; Fox, Amy C.; Clark, Andrew T.; Chang, Nai-Yuan Nicholas; Dominguez, Jessica A.; Farris, Alton B.; Buchman, Timothy G.; Hunt, Clayton R.; Coopersmith, Craig M.

    2011-01-01

    Sepsis is primarily a disease of the aged, with increased incidence and mortality occurring in aged hosts. Heat shock protein (HSP) 70 plays an important role in both healthy aging and the stress response to injury. The purpose of this study was to determine the role of HSP70 in mediating mortality and the host inflammatory response in aged septic hosts. Sepsis was induced in both young (6–12week old) and aged (16–17 month old) HSP70−/− and wild type (WT) mice to determine if HSP70 modulated outcome in an age-dependent fashion. Young HSP70−/− and WT mice subjected to cecal ligation and puncture (CLP), Pseudomonas aeruginosa pneumonia or Streptococcus pneumoniae pneumonia had no differences in mortality, suggesting HSP70 does not mediate survival in young septic hosts. In contrast, mortality was higher in aged HSP70−/− mice than aged WT mice subjected to CLP (p=0.01), suggesting HSP70 mediates mortality in sepsis in an age-dependent fashion. Compared to WT mice, aged septic HSP70−/− mice had increased gut epithelial apoptosis and pulmonary inflammation. In addition, HSP70−/−mice had increased systemic levels of TNF-α, IL-6, IL-10 and IL-1β compared to WT mice. These data demonstrate that HSP70 is a key determinant of mortality in aged but not young hosts in sepsis. HSP70 may play a protective role in an age-dependent response to sepsis by preventing excessive gut apoptosis and both pulmonary and systemic inflammation. PMID:21296977

  9. Molecular mechanisms of canalization: Hsp90 and beyond

    Indian Academy of Sciences (India)

    Madhu Sudhan

    2007-03-26

    Mar 26, 2007 ... In plants, Hsp90 function remained little characterized until recent .... unknown if Hsp90 and chromatin remodeling factors act independently or in ..... protein 90 in plant disease resistance; EMBO J. 22 5690–5699. Maloof J N ...

  10. Effect of the energy dependence of response of neutron personal dosemeters routinely used in the UK on the accuracy of dose estimation

    CERN Document Server

    Tanner, R J; Thomas, D J

    2002-01-01

    A large set of neutron energy distributions have been classified by workplace to provide a guide to the neutron fields to which workers in particular industries are likely to be exposed. These have been combined (folded) with the results of a major programme of neutron personal dosemeter response function measurements, to provide results for the systematic errors that those dosemeters would give in workplaces. Data for neutron doses recorded for UK classified workers have been taken from the CIDI tables, and related to the results from the folding process. It has hence been possible to draw conclusions about the probable systematic errors that result from the use of the currently available neutron personal dosemeters, which have inherent problems associated with their energy dependence of response.

  11. Effect of the energy dependence of response of neutron personal dosemeters routinely used in the UK on the accuracy of dose estimation

    International Nuclear Information System (INIS)

    Tanner, R.J.; Thomas, D.J.; Bartlett, D.T.

    2002-01-01

    A large set of neutron energy distributions have been classified by workplace to provide a guide to the neutron fields to which workers in particular industries are likely to be exposed. These have been combined (folded) with the results of a major programme of neutron personal dosemeter response function measurements, to provide results for the systematic errors that those dosemeters would give in workplaces. Data for neutron doses recorded for UK classified workers have been taken from the CIDI tables, and related to the results from the folding process. It has hence been possible to draw conclusions about the probable systematic errors that result from the use of the currently available neutron personal dosemeters, which have inherent problems associated with their energy dependence of response. (author)

  12. Cloning and Expression of a Cytosolic HSP90 Gene in Chlorella vulgaris

    Directory of Open Access Journals (Sweden)

    Zhengyi Liu

    2014-01-01

    Full Text Available Heat shock protein 90 (HSP90, a highly conserved molecular chaperone, plays essential roles in folding, keeping structural integrity, and regulating the subset of cytosolic proteins. We cloned the cDNA of Chlorella vulgaris HSP90 (named CvHSP90 by combining homology cloning with rapid amplification of cDNA ends (RACE. Sequence analysis indicated that CvHSP90 is a cytosolic member of the HSP90 family. Quantitative RT-PCR was applied to determine the expression level of messenger RNA (mRNA in CvHSP90 under different stress conditions. C. vulgaris was kept in different temperatures (5–45°C for 1 h. The mRNA expression level of CvHSP90 increased with temperature from 5 to 10°C, went further from 35 to 40°C, and reached the maximum at 40°C. On the other hand, for C. vulgaris kept at 35°C for different durations, the mRNA expression level of CvHSP90 increased gradually and reached the peak at 7 h and then declined progressively. In addition, the expression level of CvHSP90 at 40 or 45 in salinity (‰ was almost fourfold of that at 25 in salinity (‰ for 2 h. Therefore, CvHSP90 may be a potential biomarker to monitor environment changes.

  13. The Type II Hsp40 Sis1 cooperates with Hsp70 and the E3 ligase Ubr1 to promote degradation of terminally misfolded cytosolic protein.

    Directory of Open Access Journals (Sweden)

    Daniel W Summers

    Full Text Available Mechanisms for cooperation between the cytosolic Hsp70 system and the ubiquitin proteasome system during protein triage are not clear. Herein, we identify new mechanisms for selection of misfolded cytosolic proteins for degradation via defining functional interactions between specific cytosolic Hsp70/Hsp40 pairs and quality control ubiquitin ligases. These studies revolved around the use of S. cerevisiae to elucidate the degradation pathway of a terminally misfolded reporter protein, short-lived GFP (slGFP. The Type I Hsp40 Ydj1 acts with Hsp70 to suppress slGFP aggregation. In contrast, the Type II Hsp40 Sis1 is required for proteasomal degradation of slGFP. Sis1 and Hsp70 operate sequentially with the quality control E3 ubiquitin ligase Ubr1 to target slGFP for degradation. Compromise of Sis1 or Ubr1 function leads slGFP to accumulate in a Triton X-100-soluble state with slGFP degradation intermediates being concentrated into perinuclear and peripheral puncta. Interestingly, when Sis1 activity is low the slGFP that is concentrated into puncta can be liberated from puncta and subsequently degraded. Conversely, in the absence of Ubr1, slGFP and the puncta that contain slGFP are relatively stable. Ubr1 mediates proteasomal degradation of slGFP that is released from cytosolic protein handling centers. Pathways for proteasomal degradation of misfolded cytosolic proteins involve functional interplay between Type II Hsp40/Hsp70 chaperone pairs, PQC E3 ligases, and storage depots for misfolded proteins.

  14. A primate specific extra domain in the molecular chaperone Hsp90.

    Directory of Open Access Journals (Sweden)

    Vishwadeepak Tripathi

    Full Text Available Hsp90 (heat shock protein 90 is an essential molecular chaperone that mediates folding and quality control of client proteins. Many of them such as protein kinases, steroid receptors and transcription factors are involved in cellular signaling processes. Hsp90 undergoes an ATP hydrolysis dependent conformational cycle to assist folding of the client protein. The canonical Hsp90 shows a typical composition of three distinct domains and interacts with individual cochaperone partners such as Hop, Cdc37 and Aha1 (activator of Hsp90 ATPase that regulate the reaction cycle of the molecular chaperone. A bioinformatic survey identified an additional domain of 122 amino acids in front of the canonical Hsp90 sequence. This extra domain (E domain is specific to the Catarrhini or drooping nose monkeys, a subdivision of the higher primates that includes man, the great apes and the old world monkeys but is absent from all other species. Our biochemical analysis reveals that Hsp103 associates with cochaperone proteins such as Hop, Cdc37 and Aha1 similar to Hsp90. However, the extra domain reduces the ATP hydrolysis rate to about half when compared to Hsp90 thereby acting as a negative regulator of the molecular chaperonés intrinsic ATPase activity.

  15. Study of teflon pads as high doses dosemeters

    International Nuclear Information System (INIS)

    Teixeira, Maria Ines; Caldas, Linda V.E.

    2013-01-01

    The aim of this work is to study the Teflon, which is used as a binder in the manufacture of dosimetric tablets, for the feasibility of this material as high dose dosemeter. In this paper we used the technique of thermally stimulated luminescence (OSL) to characterize the dosimetric properties of Teflon. Teflon samples were exposed to different doses of radiation, using a source of gamma radiation ( 60 Co). It was obtained dose-response curve between 100 Gy to 50 kGy and reproducibility of OSL response. The preliminary results show that Teflon is a useful material to high dose dosimetry

  16. Changes in HSP gene and protein expression in natural scrapie with brain damage

    Science.gov (United States)

    2011-01-01

    Heat shock proteins (Hsp) perform cytoprotective functions such as apoptosis regulation and inflammatory response control. These proteins can also be secreted to the extracellular medium, acting as inflammatory mediators, and their chaperone activity permits correct folding of proteins and avoids the aggregation of anomalous isoforms. Several studies have proposed the implication of Hsp in prion diseases. We analysed the gene expression and protein distribution of different members of the Hsp27, Hsp70, and Hsp90 families in the central nervous system of sheep naturally infected with scrapie. Different expression profiles were observed in the areas analysed. Whereas changes in transcript levels were not observed in the cerebellum or medulla oblongata, a significant decrease in HSP27 and HSP90 was detected in the prefrontal cortex. In contrast, HSP73 was over-expressed in diencephalons of scrapie animals. Western blotting did not reveal significant differences in Hsp90 and Hsp70 protein expression between scrapie and control animals. Expression rates identified by real-time RT-PCR and western blotting were compared with the extent of classical scrapie lesions using stepwise regression. Changes in Hsp gene and protein expression were associated with prion protein deposition, gliosis and spongiosis rather than with apoptosis. Finally, immunohistochemistry revealed intense Hsp70 and Hsp90 immunolabelling in Purkinje cells of scrapie sheep. In contrast, controls displayed little or no staining in these cells. The observed differences in gene expression and protein distribution suggest that the heat shock proteins analysed play a role in the natural form of the disease. PMID:21314976

  17. Changes in HSP gene and protein expression in natural scrapie with brain damage

    Directory of Open Access Journals (Sweden)

    Serrano Carmen

    2011-01-01

    Full Text Available Abstract Heat shock proteins (Hsp perform cytoprotective functions such as apoptosis regulation and inflammatory response control. These proteins can also be secreted to the extracellular medium, acting as inflammatory mediators, and their chaperone activity permits correct folding of proteins and avoids the aggregation of anomalous isoforms. Several studies have proposed the implication of Hsp in prion diseases. We analysed the gene expression and protein distribution of different members of the Hsp27, Hsp70, and Hsp90 families in the central nervous system of sheep naturally infected with scrapie. Different expression profiles were observed in the areas analysed. Whereas changes in transcript levels were not observed in the cerebellum or medulla oblongata, a significant decrease in HSP27 and HSP90 was detected in the prefrontal cortex. In contrast, HSP73 was over-expressed in diencephalons of scrapie animals. Western blotting did not reveal significant differences in Hsp90 and Hsp70 protein expression between scrapie and control animals. Expression rates identified by real-time RT-PCR and western blotting were compared with the extent of classical scrapie lesions using stepwise regression. Changes in Hsp gene and protein expression were associated with prion protein deposition, gliosis and spongiosis rather than with apoptosis. Finally, immunohistochemistry revealed intense Hsp70 and Hsp90 immunolabelling in Purkinje cells of scrapie sheep. In contrast, controls displayed little or no staining in these cells. The observed differences in gene expression and protein distribution suggest that the heat shock proteins analysed play a role in the natural form of the disease.

  18. Cell stress promotes the association of phosphorylated HspB1 with F-actin.

    Directory of Open Access Journals (Sweden)

    Joseph P Clarke

    Full Text Available Previous studies have suggested that the small heat shock protein, HspB1, has a direct influence on the dynamics of cytoskeletal elements, in particular, filamentous actin (F-actin polymerization. In this study we have assessed the influence of HspB1 phosphorylation on its interaction(s with F-actin. We first determined the distribution of endogenous non-phosphorylated HspB1, phosphorylated HspB1 and F-actin in neuroendocrine PC12 cells by immunocytochemistry and confocal microscopy. We then investigated a potential direct interaction between HspB1 with F-actin by precipitating F-actin directly with biotinylated phalloidin followed by Western analyses; the reverse immunoprecipitation of HspB1 was also carried out. The phosphorylation influence of HspB1 in this interaction was investigated by using pharmacologic inhibition of p38 MAPK. In control cells, HspB1 interacts with F-actin as a predominantly non-phosphorylated protein, but subsequent to stress there is a redistribution of HspB1 to the cytoskeletal fraction and a significantly increased association of pHspB1 with F-actin. Our data demonstrate HspB1 is found in a complex with F-actin both in phosphorylated and non-phosphorylated forms, with an increased association of pHspB1 with F-actin after heat stress. Overall, our study combines both cellular and biochemical approaches to show cellular localization and direct demonstration of an interaction between endogenous HspB1 and F-actin using methodolgy that specifically isolates F-actin.

  19. Utilization of thermoluminescent dosemeters for determination of exposure or absorbed dose in a radiation gamma or X radiation field with unknown spectral distribution

    International Nuclear Information System (INIS)

    Rosa, L.A.R. da.

    1981-06-01

    Having in view the choice of the best pair of dosemeters to be used in the 'Tandem' method, the main response characteristics of LiF:Mg, Ti, Li 2 B 4 O 7 :Mn, CaSO 4 Dy, CaF 2 :Mn and CaF 2 :Dy thermoluminescent dosemeters and also some critical parameters in their calibration and evaluation processes were studied. Three different physical forms of TLD's were investigated: hot pressed chips, disc teflon dosemeters and glass mini TLD's. Their calibration factors were obtained for the energy of Cobalt-60 gamma rays. Their energy dependences normalized to 60 Co radiation were determined using spectral width as parameter. 'Tandens' formed by all TLD's evaluated were compaired. (E.G.) [pt

  20. Rice sHsp genes: genomic organization and expression profiling under stress and development

    Directory of Open Access Journals (Sweden)

    Grover Anil

    2009-08-01

    Full Text Available Abstract Background Heat shock proteins (Hsps constitute an important component in the heat shock response of all living systems. Among the various plant Hsps (i.e. Hsp100, Hsp90, Hsp70 and Hsp20, Hsp20 or small Hsps (sHsps are expressed in maximal amounts under high temperature stress. The characteristic feature of the sHsps is the presence of α-crystallin domain (ACD at the C-terminus. sHsps cooperate with Hsp100/Hsp70 and co-chaperones in ATP-dependent manner in preventing aggregation of cellular proteins and in their subsequent refolding. Database search was performed to investigate the sHsp gene family across rice genome sequence followed by comprehensive expression analysis of these genes. Results We identified 40 α-crystallin domain containing genes in rice. Phylogenetic analysis showed that 23 out of these 40 genes constitute sHsps. The additional 17 genes containing ACD clustered with Acd proteins of Arabidopsis. Detailed scrutiny of 23 sHsp sequences enabled us to categorize these proteins in a revised scheme of classification constituting of 16 cytoplasmic/nuclear, 2 ER, 3 mitochondrial, 1 plastid and 1 peroxisomal genes. In the new classification proposed herein nucleo-cytoplasmic class of sHsps with 9 subfamilies is more complex in rice than in Arabidopsis. Strikingly, 17 of 23 rice sHsp genes were noted to be intronless. Expression analysis based on microarray and RT-PCR showed that 19 sHsp genes were upregulated by high temperature stress. Besides heat stress, expression of sHsp genes was up or downregulated by other abiotic and biotic stresses. In addition to stress regulation, various sHsp genes were differentially upregulated at different developmental stages of the rice plant. Majority of sHsp genes were expressed in seed. Conclusion We identified twenty three sHsp genes and seventeen Acd genes in rice. Three nucleocytoplasmic sHsp genes were found only in monocots. Analysis of expression profiling of sHsp genes revealed

  1. Thermoluminescent dosemeter in a X-ray diffractometer

    International Nuclear Information System (INIS)

    Mendoza A, D.; Gonzalez M, P.; Falcon B, T.; Castano, V.M.

    1999-01-01

    In this work it was presented the results obtained of the dosimetry which was realized in a X-ray diffractometer for powders, trademark Siemens D5000, using the thermoluminescent signal generated by the X-rays in the commercial dosemeter TLD-100 of Harshaw, US. In according to the results obtained, the radiation quantity received by an analysed material in the diffractometer, will be proportional to exposure time and it can vary from unities until tenths of grays. These results are very outstanding when are analysed crystalline materials in a diffractometer, for knowing the present crystalline phases, mainly if these are highly sensitive to the ionizing radiation, as it is the case of the thermoluminescent materials. (Author)

  2. Active electronic personal dosemeter in interventional radiology

    International Nuclear Information System (INIS)

    Prlic, I.; Suric Mihic, M.; Vucic, Z.

    2008-01-01

    A recently developed active electronic personal dosemeter (AEPD) was utilised in order to measure the levels and the structure of occupational exposure to scattered X-ray radiation of medical staff who performed percutaneous revascularisation therapy that involves interventional radiology (IR) on the pelvis and upper leg arteries. The AEPDs, placed on the operators' and assistants' chests, that is, above the protective apron, continuously measured and recorded the received doses and, as a novelty, dose rates as a function of time, thus yielding a unique record of occupational doses and dose rates pattern at the working place. This paper presents and discusses one typical daily pattern in which seven percutaneous interventions were performed. (authors)

  3. State of the art in thermoluminescent dosimetry using dosemeters with automated read-out

    International Nuclear Information System (INIS)

    Regulla, D.F.

    1979-01-01

    In the beginning, the results obtained with automated read-out TLD have been quite disappointing, both for manufacturers and users. In response to this, industry then seeked advice and assistance from those experienced in the practical use of dosemeters, and the development of the second generation of automated TLD has been a common task of manufacturers and purchosers. As a preliminary achievement of development work along this line, a dosemeter has been presented by a Japanese manufacturer, meeting the requirements in quite a satisfactory way. The device is characterized by a frequency of disturbance of -5 , a microprocessor for controlling the measuring and control functions, possibility of active input of device parameters and boundary conditions, extensive self-control of operating functions, complete data protection, and thin-film detector technique. Pursuing this line of development, and taking into account future recommentations, automated thermoluminescent dosimetry does seem to be a promising alternative to current measuring techniques in personnel monitoring. (orig./RW) [de

  4. Hsp90: A New Player in DNA Repair?

    Directory of Open Access Journals (Sweden)

    Rosa Pennisi

    2015-10-01

    Full Text Available Heat shock protein 90 (Hsp90 is an evolutionary conserved molecular chaperone that, together with Hsp70 and co-chaperones makes up the Hsp90 chaperone machinery, stabilizing and activating more than 200 proteins, involved in protein homeostasis (i.e., proteostasis, transcriptional regulation, chromatin remodeling, and DNA repair. Cells respond to DNA damage by activating complex DNA damage response (DDR pathways that include: (i cell cycle arrest; (ii transcriptional and post-translational activation of a subset of genes, including those associated with DNA repair; and (iii triggering of programmed cell death. The efficacy of the DDR pathways is influenced by the nuclear levels of DNA repair proteins, which are regulated by balancing between protein synthesis and degradation as well as by nuclear import and export. The inability to respond properly to either DNA damage or to DNA repair leads to genetic instability, which in turn may enhance the rate of cancer development. Multiple components of the DNA double strand breaks repair machinery, including BRCA1, BRCA2, CHK1, DNA-PKcs, FANCA, and the MRE11/RAD50/NBN complex, have been described to be client proteins of Hsp90, which acts as a regulator of the diverse DDR pathways. Inhibition of Hsp90 actions leads to the altered localization and stabilization of DDR proteins after DNA damage and may represent a cell-specific and tumor-selective radiosensibilizer. Here, the role of Hsp90-dependent molecular mechanisms involved in cancer onset and in the maintenance of the genome integrity is discussed and highlighted.

  5. X and gamma reference radiation for calibrating dosemeters and doserate meters and for determining their response as a function of photon energy - Part 4: Calibration of area and personal dosemeters in low energy X reference radiation fields

    International Nuclear Information System (INIS)

    2004-01-01

    ISO 4037 consists of the following parts, under the general title X and gamma reference radiation for calibrating dosemeters and doserate meters and for determining their response as a function of photon energy: Part 1: Radiation characteristics and production methods; Part 2: Dosimetry for radiation protection over the energy ranges from 8 keV to 1,3 MeV and 4 MeV to 9 MeV; Part 3: Calibration of area and personal dosemeters and the measurement of their response as a function of energy and angle of incidence; Part 4: Calibration of area and personal dosemeters in low energy X reference radiation fields. This part 4. of ISO 4037 gives guidelines on additional aspects of the characterization of low energy photon radiations. This part of ISO 4037 also describes procedures for calibration and determination of the response of area and personal dose(rate)meters as a function of photon energy and angle of incidence. This part of ISO 4037 concentrates on the accurate determination of conversion coefficients from air kerma to Hp(10) and H*(10) for the spectra of low energy photon radiations. As an alternative to the use of conversion coefficients, the direct calibration in terms of these quantities by means of appropriate reference instruments is described

  6. Personal neutron dosemeter of the Czech Republic: Review of basic properties, results of recent tests

    Czech Academy of Sciences Publication Activity Database

    Trousil, J.; Spurný, František; Plichta, J.

    2006-01-01

    Roč. 14, 7/8 (2006), s. 246-253 ISSN 1210-7085 Institutional research plan: CEZ:AV0Z10480505 Keywords : detectors * dosemeters * personal dosimetry Subject RIV: DN - Health Impact of the Environment Quality

  7. Cell-surface expression of Hsp70 on hematopoietic cancer cells after inhibition of HDAC activity

    DEFF Research Database (Denmark)

    Jensen, Helle; Andresen, Lars; Hansen, Karen Aagaard

    Heat shock proteins (HSPs) are highly conserved molecules, which support folding of proteins under physiological conditions and mediate protection against lethal damage after various stress stimuli. Five HSP families exist defined by their molecular size (i.e. HSP100, HSP90, HSP70, HSP60, and the......Heat shock proteins (HSPs) are highly conserved molecules, which support folding of proteins under physiological conditions and mediate protection against lethal damage after various stress stimuli. Five HSP families exist defined by their molecular size (i.e. HSP100, HSP90, HSP70, HSP60...... clinically applied reagents, such as alkyl-lysophospholipides, chemotherapeutic agents, and anti-inflammatory reagents, have been found to enhance Hsp70 surface expression on cancer cells. We have found that inhibition of histone deacetylase (HDAC) activity leads to surface expression of Hsp70 on various...... hematopoietic cancer cells, an occurance that was not observed on naïve or activated peripheral blood cells. HDAC-inhibitor mediated Hsp70 surface expression was confined to the apoptotic Annexin V positive cells and blocked by inhibition of apoptosis. Other chemotherapeutic inducers of apoptosis...

  8. Effective dose assessment in the maxillofacial region using thermoluminescent (TLD) and metal oxide semiconductor field-effect transistor (MOSFET) dosemeters: a comparative study.

    Science.gov (United States)

    Koivisto, J; Schulze, D; Wolff, J; Rottke, D

    2014-01-01

    The objective of this study was to compare the performance of metal oxide semiconductor field-effect transistor (MOSFET) technology dosemeters with thermoluminescent dosemeters (TLDs) (TLD 100; Thermo Fisher Scientific, Waltham, MA) in the maxillofacial area. Organ and effective dose measurements were performed using 40 TLD and 20 MOSFET dosemeters that were alternately placed in 20 different locations in 1 anthropomorphic RANDO(®) head phantom (the Phantom Laboratory, Salem, NY). The phantom was exposed to four different CBCT default maxillofacial protocols using small (4 × 5 cm) to full face (20 × 17 cm) fields of view (FOVs). The TLD effective doses ranged between 7.0 and 158.0 µSv and the MOSFET doses between 6.1 and 175.0 µSv. The MOSFET and TLD effective doses acquired using four different (FOV) protocols were as follows: face maxillofacial (FOV 20 × 17 cm) (MOSFET, 83.4 µSv; TLD, 87.6 µSv; -5%); teeth, upper jaw (FOV, 8.5 × 5.0 cm) (MOSFET, 6.1 µSv; TLD, 7.0 µSv; -14%); tooth, mandible and left molar (FOV, 4 × 5 cm) (MOSFET, 10.3 µSv; TLD, 12.3 µSv; -16%) and teeth, both jaws (FOV, 10 × 10 cm) (MOSFET, 175 µSv; TLD, 158 µSv; +11%). The largest variation in organ and effective dose was recorded in the small FOV protocols. Taking into account the uncertainties of both measurement methods and the results of the statistical analysis, the effective doses acquired using MOSFET dosemeters were found to be in good agreement with those obtained using TLD dosemeters. The MOSFET dosemeters constitute a feasible alternative for TLDs for the effective dose assessment of CBCT devices in the maxillofacial region.

  9. Hsp27, Hsp70 and mismatch repair proteins hMLH1 and hMSH2 expression in peripheral blood lymphocytes from healthy subjects and cancer patients.

    Science.gov (United States)

    Nadin, Silvina Beatriz; Vargas-Roig, Laura M; Drago, Gisela; Ibarra, Jorge; Ciocca, Daniel R

    2007-07-08

    Mismatch repair (MMR) deficiency and higher expression levels of heat shock proteins (Hsps) have been implicated with drug resistance to topoisomerase II poisons (doxorubicin) and to platinum compounds (cisplatin). This study was designed to determine individual influences of doxorubicin and cisplatin treatment on the expression of Hsp27, Hsp70, hMLH1 and hMSH2 proteins and in the DNA damage status in peripheral blood lymphocytes (PBLs). In addition, we studied whether these proteins and the DNA damage correlated with the survival of cancer patients. PBLs from 10 healthy donors and 25 cancer patients (before and after three cycles of chemotherapy) were exposed to in vitro treatments: C (control), HS (heat shock at 42 degrees C), Do or Pt (doxorubicin or cisplatin alone), and HS+Do or HS+Pt (heat shock+doxorubicin or heat shock+cisplatin). PBLs were collected at time 0 (T0: immediately after drug treatment) and after 24h of repair (T24). Hsp27, Hsp70, hMLH1 and hMSH2 were studied by immunocytochemistry and the DNA damage by alkaline comet assay. Immunofluorescence studies and confocal microscopy revealed that hMLH1 and hMSH2 colocalized with Hsp27 and Hsp72 (inducible form of Hsp70). hMLH1 and hMSH2 were significantly induced by Pt and HS+Pt at T24 in cancer patients, but only modestly influenced by Do. Cancer patients presented higher basal expression of total and nuclear Hsp27 and Hsp70 than controls, and these proteins were also increased by HS, Do and HS+Do. The Hsp70 induction by Pt and HS+Pt was noted in cancer patients, especially nuclear Hsp70. In cancer patients, basal DNA damage was slightly higher than in healthy persons; and after Pt and HS+Pt treatments, DNA migration and number of apoptotic cells were higher than controls. Hsps accomplished a cytoprotective function in pre-chemotherapy PBLs (HS before Do or Pt), but not in post-chemotherapy samples. In Pt-treated patients the ratio N/C (nuclear/cytoplasmic) of Hsp27 was related to disease free survival

  10. Study of some characteristic dosimetric of the LIF:Mg, You (JR1152C) for their employment as environmental dosemeter

    International Nuclear Information System (INIS)

    Molina Perez, D.; Diaz Bernal, E.; Prendes Alonso, M.

    1998-01-01

    As the interest grows in knowing the effects on the health of the drops dose of natural or artificial radiation, it is made but necessary a system dosimetric able to measure those dose levels accurately. P but of twenty years the dosemeters thermoluminescent (TL) they have constituted a simple and beautiful method for such mensurations. In the work the rehearsals of homogeneity, reproducibility, line lay, detection threshold, auto irradiation, residual, fading and angular dependence are described. The results demonstrate that the dosemeter satisfies the main requirements to be an employee in the environmental monitoring

  11. Stress-induced localization of HSPA6 (HSP70B') and HSPA1A (HSP70-1) proteins to centrioles in human neuronal cells.

    Science.gov (United States)

    Khalouei, Sam; Chow, Ari M; Brown, Ian R

    2014-05-01

    The localization of yellow fluorescent protein (YFP)-tagged HSP70 proteins was employed to identify stress-sensitive sites in human neurons following temperature elevation. Stable lines of human SH-SY5Y neuronal cells were established that expressed YFP-tagged protein products of the human inducible HSP70 genes HSPA6 (HSP70B') and HSPA1A (HSP70-1). Following a brief period of thermal stress, YFP-tagged HSPA6 and HSPA1A rapidly appeared at centrioles in the cytoplasm of human neuronal cells, with HSPA6 demonstrating a more prolonged signal compared to HSPA1A. Each centriole is composed of a distal end and a proximal end, the latter linking the centriole doublet. The YFP-tagged HSP70 proteins targeted the proximal end of centrioles (identified by γ-tubulin marker) rather than the distal end (centrin marker). Centrioles play key roles in cellular polarity and migration during neuronal differentiation. The proximal end of the centriole, which is involved in centriole stabilization, may be stress-sensitive in post-mitotic, differentiating human neurons.

  12. Perbedaan Kadar HSP90 pada Preeklamsi Berat dengan Kehamilan Normal

    Directory of Open Access Journals (Sweden)

    Soetrisno

    2015-06-01

    Full Text Available Severe pre-eclampsia is the second highest cause of maternal mortality. Free radicals that stimulate heat shock protein 90 (HSP 90 are believed to determine severe pre-eclampsia. HSP90 is an important protein that helps the establishment and maintenance of other proteins. It also increases the life time of cells after various pathological conditions (chaperone function. The chaperone function is the adaptation key factor to endogenous stress in tissues. By recognizing HSP90 level in early detection of severe pre-eclampsia, prevention and management can be started early. This study aimed to prove that the HSP90 level in pregnancy with severe pre-eclampsia is higher than normal pregnancy. This was a quantitative study using cross sectional approach by testing the HSP90 level. The study was conducted during the period of September to November 2013, at the Obstetrics and Gynecological Unit, Moewardi Hospital Surakarta and Prodia Laboratory Jakarta. The number of subjects was 30 patients, consisting of 15 normal pregnant mothers and 15 pregnant mothers with pre-eclampsia . The calculation of serum HSP90 level was conducted using enzyme-linked immunosorbent assay (ELISA. Data were analyzed using t-test using SPSS for Windows version 17 for Windows. The mean of HSP90 in the severe pre-eclampsia group was 131.91±26.66 while the mean in the normal pregnancy group was 80.28±13.39 with p=0.00 (p<0.05. Level of HSP90 serum in severe pre-eclampsia is higher than in normal pregnancy, due to the occurrence of oxidative stress in severe pre-eclampsia

  13. Identification and in silico analysis of the Citrus HSP70 molecular chaperone gene family

    Directory of Open Access Journals (Sweden)

    Luciano G. Fietto

    2007-01-01

    Full Text Available The completion of the genome sequencing of the Arabidopsis thaliana model system provided a powerful molecular tool for comparative analysis of gene families present in the genome of economically relevant plant species. In this investigation, we used the sequences of the Arabidopsis Hsp70 gene family to identify and annotate the Citrus Hsp70 genes represented in the CitEST database. Based on sequence comparison analysis, we identified 18 clusters that were further divided into 5 subgroups encoding four mitochondrial mtHsp70s, three plastid csHsp70s, one ER luminal Hsp70 BiP, two HSP110/SSE-related proteins and eight cytosolic Hsp/Hsc70s. We also analyzed the expression profile by digital Northern of each Hsp70 transcript in different organs and in response to stress conditions. The EST database revealed a distinct population distribution of Hsp70 ESTs among isoforms and across the organs surveyed. The Hsp70-5 isoform was highly expressed in seeds, whereas BiP, mitochondrial and plastid HSp70 mRNAs displayed a similar expression profile in the organs analyzed, and were predominantly represented in flowers. Distinct Hsp70 mRNAs were also differentially expressed during Xylella infection and Citrus tristeza viral infection as well as during water deficit. This in silico study sets the groundwork for future investigations to fully characterize functionally the Citrus Hsp70 family and underscores the relevance of Hsp70s in response to abiotic and biotic stresses in Citrus.

  14. Expression of Hsp27 and Hsp70 and vacuolization in the pituitary glands in cases of fatal hypothermia.

    Science.gov (United States)

    Doberentz, Elke; Markwerth, Philipp; Wagner, Rebecca; Madea, Burkhard

    2017-09-01

    Hypothermia causes systemic cellular stress. The pituitary gland is an endocrine gland and plays an important role in thermoregulation. When the core body temperature drops, the pituitary gland is activated by stimulation of hypothalamic hormones. In this study, we investigated morphological alterations of the pituitary gland in cases of fatal hypothermia. Several morphological alterations of the anterior lobe of the pituitary gland, such as hemorrhage, vacuolization, and hyperemia, have been previously described in fatal hypothermia. However, the diagnostic value of these findings is controversial. We compared 11 cases of fatal hypothermia with 10 cases lacking antemortem hypothermic influences. In the presence of thermal cellular stress, the expression of heat shock proteins increases to protect cellular structures. Therefore, we immunohistochemically analyzed Hsp27 and Hsp70. Hsp27 expression was detected in 27.3% of the cases of fatal hypothermia and in 10.0% of the control cases, whereas Hsp70 expression was not detected in any case. Additionally, Sudan staining was performed to quantify fatty degeneration. A positive reaction was found in 45.5% of the study group and in 10.0% of the control group. This indicates that fatty degeneration might be a valuable marker when other macroscopic signs of hypothermia are absent.

  15. Cat exposure induces both intra- and extracellular Hsp72: the role of adrenal hormones.

    Science.gov (United States)

    Fleshner, Monika; Campisi, Jay; Amiri, Leila; Diamond, David M

    2004-10-01

    Heat-shock proteins (Hsp) play an important role in stress physiology. Exposure to a variety of stressors will induce intracellular Hsp72, and this induction is believed to be beneficial for cell survival. In contrast, Hsp72 released during stress (extracellular Hsp72; eHsp72) activates pro-inflammatory responses. Clearly, physical stressors such as heat, cold, H(2)O(2), intense exercise and tail shock will induce both intra- and extracellular Hsp72. The current study tested whether a psychological stressor, cat exposure, would also trigger this response. In addition, the potential role of adrenal hormones in the Hsp72 response was examined. Adult, male Sprague Dawley rats were either adrenalectomized (ADX) or sham operated. Ten days post-recovery, rats were exposed to either a cat with no physical contact or control procedures (n = 5-6/group) for 2 h. Levels of intracellular Hsp72 were measured in the brain (frontal cortex, hippocampus, hypothalamus, dorsal vagal complex) and pituitary (ELISA). Levels of eHsp72 (ELISA) and corticosterone (RIA) were measured from serum obtained at the end of the 2-h stress period. Rats that were exposed to a cat had elevated intracellular Hsp72 in hypothalamus and dorsal vagal complex, and elevated eHsp72 and corticosterone in serum. Both the intra- and extracellular Hsp72 responses were blocked or attenuated by ADX. This study demonstrates that cat exposure can stimulate the Hsp72 response and that adrenal hormones contribute to this response.

  16. Comprehensive identification and expression analysis of Hsp90s gene family in Solanum lycopersicum.

    Science.gov (United States)

    Zai, W S; Miao, L X; Xiong, Z L; Zhang, H L; Ma, Y R; Li, Y L; Chen, Y B; Ye, S G

    2015-07-14

    Heat shock protein 90 (Hsp90) is a protein produced by plants in response to adverse environmental stresses. In this study, we identified and analyzed Hsp90 gene family members using a bioinformatic method based on genomic data from tomato (Solanum lycopersicum L.). The results illustrated that tomato contains at least 7 Hsp90 genes distributed on 6 chromosomes; protein lengths ranged from 267-794 amino acids. Intron numbers ranged from 2-19 in the genes. The phylogenetic tree revealed that Hsp90 genes in tomato (Solanum lycopersicum L.), rice (Oryza sativa L.), and Arabidopsis (Arabidopsis thaliana L.) could be divided into 5 groups, which included 3 pairs of orthologous genes and 4 pairs of paralogous genes. Expression analysis of RNA-sequence data showed that the Hsp90-1 gene was specifically expressed in mature fruits, while Hsp90-5 and Hsp90-6 showed opposite expression patterns in various tissues of cultivated and wild tomatoes. The expression levels of the Hsp90-1, Hsp90-2, and Hsp90- 3 genes in various tissues of cultivated tomatoes were high, while both the expression levels of genes Hsp90-3 and Hsp90-4 were low. Additionally, quantitative real-time polymerase chain reaction showed that these genes were involved in the responses to yellow leaf curl virus in tomato plant leaves. Our results provide a foundation for identifying the function of the Hsp90 gene in tomato.

  17. Noradrenaline increases the expression and release of Hsp72 by human neutrophils.

    Science.gov (United States)

    Giraldo, E; Multhoff, G; Ortega, E

    2010-05-01

    The blood concentration of extracellular 72kDa heat shock protein (eHsp72) increases under conditions of stress, including intense exercise. However, the signal(s), source(s), and secretory pathways in its release into the bloodstream have yet to be clarified. The aim of the present study was to evaluate the role of noradrenaline (NA) as a stress signal on the expression and release of Hsp72 by circulating neutrophils (as a source), all within a context of the immunophysiological regulation during exercise-induced stress in sedentary and healthy young (21-26years) women. The expression of Hsp72 on the surface of isolated neutrophils was determined by flow cytometry, and its release by cultured isolated neutrophils was determined by ELISA. Incubation with cmHsp70-FITC showed that neutrophils express Hsp72 on their surface under basal conditions. In addition, cultured isolated neutrophils (37 degrees C and 5% CO(2)) also released Hsp72 under basal conditions, with this release increasing from 10min to 24h in the absence of cell damage. NA at 10(-9)-10(-5)M doubled the percentage of neutrophils expressing Hsp72 after 60min and 24h incubation. NA also stimulated (by about 20%) the release of Hsp72 after 10min of incubation. (1) Hsp72 is expressed on the surface of isolated neutrophils under basal conditions, and this expression is augmented by NA. (2) Isolated neutrophils can also release Hsp72 under cultured basal conditions in the absence of cell death, and NA can increase this release. These results may contribute to confirming the hypothesis that NA can act as a "stress signal" for the increased eHsp72 in the context of exercise stress, with a role for neutrophils as a source for the expression and, to a lesser degree, the release of Hsp72 after activation by NA. Copyright 2010 Elsevier Inc. All rights reserved.

  18. Preparation of the FXG gel dosemeter and studying its response for low and medium energy X-rays

    International Nuclear Information System (INIS)

    Bero, M.; Kharita, M. H.

    2008-02-01

    Gel dosimetry method was found to be capable of addressing complicated issues related to dose measurements particularly in modern sophisticated radiotherapy applications. Ferrous-sulphate Xylenol-orange and Gelatin (FXG) radiochromic gel dosemeter is one of the systems used for such applications. Some chemical dosemeters show different response for low and medium energies X-rays in comparison with high energy-photons. The energy and dose rate dependence of the FXG dose response was examined. In addition to the detector response other important dosimetric properties of the system were investigated for different X-ray beam qualities with tube voltages in the range 100 - 300 kv. An orthovoltage X-ray therapy unit was used to irradiate standard sized samples of FXG from different batches for radiation doses in the range 0 - 8 Gy. This work includes in the first stage the preparation of the radiochromic gel dosemeter (FXG) as well as its calibration in gamma radiation field. Furthermore, the stability and reproducibility of measurements were tested. The obtained results were found to be suitable as a basis to carry on the next stage of this study. The second phase was centred about the delivery of radiation doses from X-ray source that has increasing energy and evaluating the gel material properties as a dosemeter in this case, with concentration on finding the changes of the gel material response with the changes in the applied X-ray energy. Therefore establishing the response radiation energy dependence and comparing the measurement results with other results taken from other known dosimetry system such as ion chambers. Experiments shows that the FXG gel detector has a dynamic rage suitable for the dose delivered in radiotherapy treatment; its response as a function of the dose rate is also stable in the range of radiation energies applied.(Author)

  19. KADAR MDA DAN HSP 70 PADA PLASENTA PENDERITA PREEKLAMPSIA

    Directory of Open Access Journals (Sweden)

    Arleni

    2008-12-01

    Full Text Available The MDA and HSP70 Concentration in Preeclamptic Patient Placenta’s. Objective: Preeclampsia is a disease in pregnancy and characterized by hypertension and proteinuria. Preeclampsia and eclampsia are the most causes of maternal and fetal mortality and morbidity in Indonesia. Placental and systemic oxidative stress caused endothelial cell dysfunction and injury. Placental oxidative stress also linked to fetal growth restriction. HSP70 is essential for cellular recovery, survival and maintenance of homeostasis. The purpose of this study was to compare the MDA, a marker for oxidative stress and HSP70 production in placental of severe preeclampsia, mild preeclampsia and normotensive pregnant women. Placenta were collected after delivery from normotensive pregnancies (N=10, severe preeclampsia (N=10 and mild preeclampsia (N=10. Placenta was cultured in RPMI and 20% FBS, and supernatant were collected in day 3. MDA was measured using spectrophotometer and absorbance read in 530nm. HSP70 was measured using enzyme-linked immunosorbent assay. The mean MDA concentration did not differ significantly between patients with severe preeclampsia (7.13+5.36 nmol/ml and mild preeclampsia (4.82+2.47 nmol/ml when compared with normotensive pregnancies (4.57+2.4 nmol/ml. The mean HSP70 concentration in mild preeclampsia is highest (10.15+12.39 nmo/ml when compared with severe preeclampsia (3.78 +3.07 nmol/ml and normotensive pregnant women (3.76+4.65nmol/ml, but the difference was not significant. Although the difference was not significant, is indicates homeostasis response in mild preclampsia women is relative good. This response was abated in severe preeclampstic women. Although MDA and HSP70 concentration did not differ significantly between groups, however the high HSP70 concentration is indicates homeostasis response relatively good in mild preeclamptic women.

  20. A measurement of the response to fast neutrons of several materials dosemeters

    International Nuclear Information System (INIS)

    Jones, L.T.; Kitching, S.J.; Lewis, T.A.; Playle, T.S.

    1986-07-01

    The response to fast neutrons was measured for three types of materials testing dosemeters: fast neutron dosimetry silicon diodes; beryllia, alumina and calcium fluoride TLDs; graphite walled ionisation chambers. The calibrations were made using a 3MW positive ion accelerator. The arrangement of the target, beam monitor and devices is described, and the measured fast neutron sensitivities are presented. (UK)

  1. Expression profile of HSP genes during different seasons in goats (Capra hircus).

    Science.gov (United States)

    Dangi, Satyaveer Singh; Gupta, Mahesh; Maurya, Divakar; Yadav, Vijay Prakash; Panda, Rudra Prasanna; Singh, Gyanendra; Mohan, Nitai Haridas; Bhure, Sanjeev Kumar; Das, Bikash Chandra; Bag, Sadhan; Mahapatra, Ramkrishna; Taru Sharma, Guttalu; Sarkar, Mihir

    2012-12-01

    The present study has demonstrated the expression of HSP60, HSP70, HSP90, and UBQ in peripheral blood mononuclear cells (PBMCs) during different seasons in three different age groups (Groups I, II, and III with age of 0-2, 2-5, and >5 years, respectively) of goats of tropical and temperate regions. Real-time polymerase chain reaction was applied to investigate mRNA expression of examined factors. Specificity of the desired products was documented using analysis of the melting temperature and high-resolution gel electrophoresis to verify that the transcripts are of the exact molecular size predicted. The mRNA expression of HSP60, HSP90, and UBQ was significantly higher (P tropical and temperate region goats. HSP70 mRNA expression was significantly higher (P tropical region goats. However, in the temperate region, in goats from all the three age groups studied, a non-significant difference of HSP70 expression between summer and winter seasons was noticed. In conclusion, results demonstrate that (1) HSP genes are expressed in caprine PBMCs and (2) higher expression of HSPs during thermal stress suggest possible involvement of them to ameliorate deleterious effect of thermal stress so as to maintain cellular integrity and homeostasis in goats.

  2. Heat Shock Protein 90 (Hsp90 Expression and Breast Cancer

    Directory of Open Access Journals (Sweden)

    Christos A. Papadimitriou

    2012-09-01

    Full Text Available Hsp90 is an abundant protein in mammalian cells. It forms several discrete complexes, each containing distinct groups of co-chaperones that assist protein folding and refolding during stress, protein transport and degradation. It interacts with a variety of proteins that play key roles in breast neoplasia including estrogen receptors, tumor suppressor p53 protein, angiogenesis transcription factor HIF-1alpha, antiapoptotic kinase Akt, Raf-1 MAP kinase and a variety of receptor tyrosine kinases of the erbB family. Elevated Hsp90 expression has been documented in breast ductal carcinomas contributing to the proliferative activity of breast cancer cells; whilst a significantly decreased Hsp90 expression has been shown in infiltrative lobular carcinomas and lobular neoplasia. Hsp90 overexpression has been proposed as a component of a mechanism through which breast cancer cells become resistant to various stress stimuli. Therefore, pharmacological inhibition of HSPs can provide therapeutic opportunities in the field of cancer treatment. 17-allylamino,17-demethoxygeldanamycin is the first Hsp90 inhibitor that has clinically been investigated in phase II trial, yielding promising results in patients with HER2-overexpressing metastatic breast cancer, whilst other Hsp90 inhibitors (retaspimycin HCL, NVP-AUY922, NVP-BEP800, CNF2024/BIIB021, SNX-5422, STA-9090, etc. are currently under evaluation.

  3. Heat Shock Protein HSP27 Secretion by Ovarian Cancer Cells Is Linked to Intracellular Expression Levels, Occurs Independently of the Endoplasmic Reticulum Pathway and HSP27’s Phosphorylation Status, and Is Mediated by Exosome Liberation

    Directory of Open Access Journals (Sweden)

    Matthias B. Stope

    2017-01-01

    Full Text Available The heat shock protein HSP27 has been correlated in ovarian cancer (OC patients with aggressiveness and chemoresistance and, therefore, represents a promising potential biomarker for OC diagnosis, prognosis, and treatment response. Notably, secretion of soluble HSP27 has been described by a few cell types and may take place as well in OC cells. Therefore, we studied HSP27 secretion mechanisms under diverse cellular conditions in an OC cell model system. Secretion of HSP27 was characterized after overexpression of HSP27 by transfected plasmids and after heat shock. Intra- and extracellular HSP27 amounts were assessed by Western blotting and ELISA. Protein secretion was blocked by brefeldin A and the impact of the HSP27 phosphorylation status was analyzed overexpressing HSP27 phosphomutants. The present study demonstrated that HSP27 secretion by OVCAR-3 and SK-OV-3 cells depends on intracellular HSP27 concentrations. Moreover, HSP27 secretion is independent of the endoplasmic reticulum secretory pathway and HSP27 phosphorylation. Notably, analysis of OC cell-born exosomes not only confirmed the concentration-dependent correlation of HSP27 expression and secretion but also demonstrated a concentration-dependent incorporation of HSP27 protein into exosomes. Thus, secreted HSP27 may become more important as an extracellular factor which controls the tumor microenvironment and might be a noninvasive biomarker.

  4. High mobility group protein DSP1 negatively regulates HSP70 transcription in Crassostrea hongkongensis

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Zongyu; Xu, Delin; Cui, Miao; Zhang, Qizhong, E-mail: zhangqzdr@126.com

    2016-06-10

    HSP70 acts mostly as a molecular chaperone and plays important roles in facilitating the folding of nascent peptides as well as the refolding or degradation of the denatured proteins. Under stressed conditions, the expression level of HSP70 is upregulated significantly and rapidly, as is known to be achieved by various regulatory factors controlling the transcriptional level. In this study, a high mobility group protein DSP1 was identified by DNA-affinity purification from the nuclear extracts of Crassostrea hongkongensis using the ChHSP70 promoter as a bait. The specific interaction between the prokaryotically expressed ChDSP1 and the FITC-labeled ChHSP70 promoter was confirmed by EMSA analysis. ChDSP1 was shown to negatively regulate ChHSP70 promoter expression by Luciferase Reporter Assay in the heterologous HEK293T cells. Both ChHSP70 and ChDSP1 transcriptions were induced by either thermal or CdCl{sub 2} stress, while the accumulated expression peaks of ChDSP1 were always slightly delayed when compared with that of ChHSP70. This indicates that ChDSP1 is involved, very likely to exert its suppressive role, in the recovery of the ChHSP70 expression from the induced level to its original state. This study is the first to report negative regulator of HSP70 gene transcription, and provides novel insights into the mechanisms controlling heat shock protein expression. -- Highlights: •HMG protein ChDSP1 shows affinity to ChHSP70 promoter in Crassostrea hongkongensis. •ChDSP1 negatively regulates ChHSP70 transcription. •ChHSP70 and ChDSP1 transcriptions were coordinately induced by thermal/Cd stress. •ChDSP1 may contribute to the recovery of the induced ChHSP70 to its original state. •This is the first report regarding negative regulator of HSP70 transcription.

  5. Hsp90 governs echinocandin resistance in the pathogenic yeast Candida albicans via calcineurin.

    Directory of Open Access Journals (Sweden)

    Sheena D Singh

    2009-07-01

    Full Text Available Candida albicans is the leading fungal pathogen of humans, causing life-threatening disease in immunocompromised individuals. Treatment of candidiasis is hampered by the limited number of antifungal drugs whose efficacy is compromised by host toxicity, fungistatic activity, and the emergence of drug resistance. We previously established that the molecular chaperone Hsp90, which regulates the form and function of diverse client proteins, potentiates resistance to the azoles in C. albicans and in the model yeast Saccharomyces cerevisiae. Genetic studies in S. cerevisiae revealed that Hsp90's role in azole resistance is to enable crucial cellular responses to the membrane stress exerted by azoles via the client protein calcineurin. Here, we demonstrate that Hsp90 governs cellular circuitry required for resistance to the only new class of antifungals to reach the clinic in decades, the echinocandins, which inhibit biosynthesis of a critical component of the fungal cell wall. Pharmacological or genetic impairment of Hsp90 function reduced tolerance of C. albicans laboratory strains and resistance of clinical isolates to the echinocandins and created a fungicidal combination. Compromising calcineurin function phenocopied compromising Hsp90 function. We established that calcineurin is an Hsp90 client protein in C. albicans: reciprocal co-immunoprecipitation validated physical interaction; Hsp90 inhibition blocked calcineurin activation; and calcineurin levels were depleted upon genetic reduction of Hsp90. The downstream effector of calcineurin, Crz1, played a partial role in mediating calcineurin-dependent stress responses activated by echinocandins. Hsp90's role in echinocandin resistance has therapeutic potential given that genetic compromise of C. albicans HSP90 expression enhanced the efficacy of an echinocandin in a murine model of disseminated candidiasis. Our results identify the first Hsp90 client protein in C. albicans, establish an entirely

  6. Validation of response simulation methodology of Albedo dosemeter; Validacao da metodologia de simulacao de resposta de dosimetro de Albedo

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, B.M.; Silva, A.X. da, E-mail: bfreitas@nuclear.ufrj.br [Coordenacao do Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Mauricio, C.L.P. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2016-07-01

    The Instituto de Radioprotecao e Dosimetria developed and runs a neutron TLD albedo individual monitoring service. To optimize the dose calculation algorithm and to infer new calibration factors, the response of this dosemeter was simulated. In order to validate this employed methodology, it was applied in the simulation of the problem of the QUADOS (Quality Assurance of Computational Tools for Dosimetry) intercomparison, aimed to evaluate dosimetric problems, one being to calculate the response of a generic albedo dosemeter. The obtained results were compared with those of other modeling and the reference one, with good agreements. (author)

  7. Effects of HSP27 chaperone on THP-1 tumor cell apoptosis.

    Science.gov (United States)

    Kaigorodova, E V; Ryazantseva, N V; Novitskii, V V; Maroshkina, A N; Belkina, M V

    2012-11-01

    The role of Hsp27 (heat shock protein 27) chaperone in regulation of THP-1 tumor cell apoptosis was studied. Realization of tumor cell apoptosis under conditions of in vitro culturing with Hsp27 specific inhibitor (KRIBB3) was evaluated by fluorescent microscopy with FITC-labeled annexin V and propidium iodide. Measurements of Bcl-2 family proteins (Bcl-2, Bax, Bad) in tumor cells incubated with Hsp27 inhibitor were carried out by Western blotting. Chaperone Hsp27 acted as apoptosis inhibitor in THP-1 tumor cells modulating the proportion of antiapoptotic (Bcl-2) and proapoptotic (Bax and Bad) proteins.

  8. Type testing of the Siemens Plessey electronic personal dosemeter.

    Science.gov (United States)

    Hirning, C R; Yuen, P S

    1995-07-01

    This paper presents the results of a laboratory assessment of the performance of a new type of personal dosimeter, the Electronic Personal Dosemeter made by Siemens Plessey Controls Limited. Twenty pre-production dosimeters and a reader were purchased by Ontario Hydro for the assessment. Tests were performed on radiological performance, including reproducibility, accuracy, linearity, detection threshold, energy response, angular response, neutron response, and response time. There were also tests on the effects of a variety of environmental factors, such as temperature, humidity, pulsed magnetic and electric fields, low- and high-frequency electromagnetic fields, light exposure, drop impact, vibration, and splashing. Other characteristics that were tested were alarm volume, clip force, and battery life. The test results were compared with the relevant requirements of three standards: an Ontario Hydro standard for personal alarming dosimeters, an International Electrotechnical Commission draft standard for direct reading personal dose monitors, and an International Electrotechnical Commission standard for thermoluminescence dosimetry systems for personal monitoring. In general, the performance of the Electronic Personal Dosemeter was found to be quite acceptable: it met most of the relevant requirements of the three standards. However, the following deficiencies were found: slow response time; sensitivity to high-frequency electromagnetic fields; poor resistance to dropping; and an alarm that was not loud enough. In addition, the response of the electronic personal dosimeter to low-energy beta rays may be too low for some applications. Problems were experienced with the reliability of operation of the pre-production dosimeters used in these tests.

  9. Review: The HSP90 molecular chaperone-an enigmatic ATPase.

    Science.gov (United States)

    Pearl, Laurence H

    2016-08-01

    The HSP90 molecular chaperone is involved in the activation and cellular stabilization of a range of 'client' proteins, of which oncogenic protein kinases and nuclear steroid hormone receptors are of particular biomedical significance. Work over the last two decades has revealed a conformational cycle critical to the biological function of HSP90, coupled to an inherent ATPase activity that is regulated and manipulated by many of the co-chaperones proteins with which it collaborates. Pharmacological inhibition of HSP90 ATPase activity results in degradation of client proteins in vivo, and is a promising target for development of new cancer therapeutics. Despite this, the actual function that HSP90s conformationally-coupled ATPase activity provides in its biological role as a molecular chaperone remains obscure. © 2016 Wiley Periodicals, Inc. Biopolymers 105: 594-607, 2016. © 2016 The Authors. Biopolymers Published by Wiley Periodicals, Inc.

  10. Increased levels of IgG antibodies against human HSP60 in patients with spondyloarthritis

    DEFF Research Database (Denmark)

    Hjelholt, Astrid; Carlsen, Thomas Gelsing; Deleuran, Bent Winding

    2013-01-01

    Introduction: Spondyloarthritis (SpA) comprises a heterogeneous group of inflammatory diseases, with strong association to human leukocyte antigen (HLA)-B27. SpA is suggested triggered by bacterial infection, and bacterial heat shock protein (HSP) seems to be a strong T cell antigen. Since...... against human HSP60, but not antibodies against bacterial HSP60, were elevated in the SpA group compared with the control group. Association between IgG3 antibodies against human HSP60 and BASMI was shown in HLA-B27+ patients. Only weak correlation between antibodies against bacterial and human HSP60...... was seen, and there was no indication of cross-reaction. Conclusion: These results suggest that antibodies against human HSP60 is associated with SpA, however, the theory that antibodies against human HSP60 is a specific part of the aetiology, through cross-reaction to bacterial HSP60, cannot be supported...

  11. Recovery From Radiation-induced Bone Marrow Damage by HSP25 Through Tie2 Signaling

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hae-June [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kwon, Hee-Chung [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Chung, Hee-Yong [College of Medicine, Hanyang University, Seoul (Korea, Republic of); Lee, Yoon-Jin [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Yun-Sil, E-mail: yslee0425@ewha.ac.kr [College of Pharmacy and Division of Life and Pharmaceutical Sciences, Ewha Woman' s University, Seoul (Korea, Republic of)

    2012-09-01

    Purpose: Whole-body radiation therapy can cause severe injury to the hematopoietic system, and therefore it is necessary to identify a novel strategy for overcoming this injury. Methods and Materials: Mice were irradiated with 4.5 Gy after heat shock protein 25 (HSP25) gene transfer using an adenoviral vector. Then, peripheral blood cell counts, histopathological analysis, and Western blotting on bone marrow (BM) cells were performed. The interaction of HSP25 with Tie2 was investigated with mouse OP9 and human BM-derived mesenchymal stem cells to determine the mechanism of HSP25 in the hematopoietic system. Results: HSP25 transfer increased BM regeneration and reduced apoptosis following whole-body exposure to ionizing radiation (IR). The decrease in Tie2 protein expression that followed irradiation of the BM was blocked by HSP25 transfer, and Tie2-positive cells were more abundant among the BM cells of HSP25-transferred mice, even after IR exposure. Following systemic RNA interference of Tie2 before IR, HSP25-mediated radioprotective effects were partially blocked in both mice and cell line systems. Stability of Tie2 was increased by HSP25, a response mediated by the interaction of HSP25 with Tie2. IR-induced tyrosine phosphorylation of Tie2 was augmented by HSP25 overexpression; downstream events in the Tie2 signaling pathway, including phosphorylation of AKT and EKR1/2, were also activated. Conclusions: HSP25 protects against radiation-induced BM damage by interacting with and stabilizing Tie2. This may be a novel strategy for HSP25-mediated radioprotection in BM.

  12. Recruitment of phosphorylated small heat shock protein Hsp27 to nuclear speckles without stress

    International Nuclear Information System (INIS)

    Bryantsev, A.L.; Chechenova, M.B.; Shelden, E.A.

    2007-01-01

    During stress, the mammalian small heat shock protein Hsp27 enters cell nuclei. The present study examines the requirements for entry of Hsp27 into nuclei of normal rat kidney (NRK) renal epithelial cells, and for its interactions with specific nuclear structures. We find that phosphorylation of Hsp27 is necessary for the efficient entry into nuclei during heat shock but not sufficient for efficient nuclear entry under control conditions. We further report that Hsp27 is recruited to an RNAse sensitive fraction of SC35 positive nuclear speckles, but not other intranuclear structures, in response to heat shock. Intriguingly, Hsp27 phosphorylation, in the absence of stress, is sufficient for recruitment to speckles found in post-anaphase stage mitotic cells. Additionally, pseudophosphorylated Hsp27 fused to a nuclear localization peptide (NLS) is recruited to nuclear speckles in unstressed interphase cells, but wildtype and nonphosphorylatable Hsp27 NLS fusion proteins are not. The expression of NLS-Hsp27 mutants does not enhance colony forming abilities of cells subjected to severe heat shock, but does regulate nuclear speckle morphology. These data demonstrate that phosphorylation, but not stress, mediates Hsp27 recruitment to an RNAse soluble fraction of nuclear speckles and support a site-specific role for Hsp27 within the nucleus

  13. The Effects of Hsp90α1 Mutations on Myosin Thick Filament Organization.

    Science.gov (United States)

    He, Qiuxia; Liu, Kechun; Tian, Zhenjun; Du, Shao Jun

    2015-01-01

    Heat shock protein 90α plays a key role in myosin folding and thick filament assembly in muscle cells. To assess the structure and function of Hsp90α and its potential regulation by post-translational modification, we developed a combined knockdown and rescue assay in zebrafish embryos to systematically analyze the effects of various mutations on Hsp90α function in myosin thick filament organization. DNA constructs expressing the Hsp90α1 mutants with altered putative ATP binding, phosphorylation, acetylation or methylation sites were co-injected with Hsp90α1 specific morpholino into zebrafish embryos. Myosin thick filament organization was analyzed in skeletal muscles of the injected embryos by immunostaining. The results showed that mutating the conserved D90 residue in the Hsp90α1 ATP binding domain abolished its function in thick filament organization. In addition, phosphorylation mimicking mutations of T33D, T33E and T87E compromised Hsp90α1 function in myosin thick filament organization. Similarly, K287Q acetylation mimicking mutation repressed Hsp90α1 function in myosin thick filament organization. In contrast, K206R and K608R hypomethylation mimicking mutations had not effect on Hsp90α1 function in thick filament organization. Given that T33 and T87 are highly conserved residues involved post-translational modification (PTM) in yeast, mouse and human Hsp90 proteins, data from this study could indicate that Hsp90α1 function in myosin thick filament organization is potentially regulated by PTMs involving phosphorylation and acetylation.

  14. Structural model of dodecameric heat-shock protein Hsp21

    DEFF Research Database (Denmark)

    Rutsdottir, Gudrun; Härmark, Johan; Weide, Yoran

    2017-01-01

    for investigating structure-function relationships of Hsp21 and understanding these sequence variations, we developed a structural model of Hsp21 based on homology modeling, cryo-EM, cross-linking mass spectrometry, NMR, and small-angle X-ray scattering. Our data suggest a dodecameric arrangement of two trimer...

  15. The expression of HSP27 is associated with poor clinical outcome in intrahepatic cholangiocarcinoma

    International Nuclear Information System (INIS)

    Romani, Antonello A; Crafa, Pellegrino; Desenzani, Silvia; Graiani, Gallia; Lagrasta, Costanza; Sianesi, Mario; Soliani, Paolo; Borghetti, Angelo F

    2007-01-01

    The heat shock proteins (HSPs) 27-kDa (HSP27) and 72-kDa (HSP72), are ubiquitous chaperone molecules inducible in cells exposed to different stress conditions. Increased level of HSPs are reported in several human cancers, and found to be associated with the resistance to some anticancer treatments and poor prognosis. However, there is no study of the relationship between HSPs expression and patient's prognosis in intrahepatic cholangiocarcinoma (IHCCA). In this exploratory retrospective study, we investigated the expressions of HSP27 and HSP72 as potential prognostic factors in IHCCA. Thirty-one paraffin-embedded samples were analyzed by immunohistochemical methods using HSP27 and HSP72 monoclonal antibodies. Proliferation rate was assessed in the same specimens by using monoclonal antibody against phosphorylated histone H3 (pHH3). Fisher's exact test was used to assess the hypothesis of independence between categorical variables in 2 × 2 tables. The ANOVA procedure was used to evaluate the association between ordinal and categorical variables. Estimates of the survival probability were calculated using the Kaplan-Meier method, and the log rank test was employed to test the null hypothesis of equality in overall survival among groups. The hazard ratio associated with HSP27 and HSP72 expression was estimated by Cox hazard-proportional regression. The expression of HSP27 was related to mitotic index, tumor greatest dimension, capsular and vascular invasion while the expression of HSP72 was only related to the presence of necrosis and the lymphoid infiltration. Kaplan-Maier analysis suggested that the expression of HSP27 significantly worsened the patients' median overall survival (11 ± 3.18 vs 55 ± 4.1 months, P-value = 0.0003). Moreover HSP27-positive patients exhibited the worst mean survival (7.0 ± 3.2 months) in the absence of concomitant HSP72 expression. The expression of HSP27, likely increasing cell proliferation, tumor mass, vascular and

  16. Chlamydia trachomatis Infection and Anti-Hsp60 Immunity: The Two Sides of the Coin

    Science.gov (United States)

    Cappello, Francesco; Conway de Macario, Everly; Di Felice, Valentina; Zummo, Giovanni; Macario, Alberto J. L.

    2009-01-01

    Chlamydia trachomatis (CT) infection is one of the most common causes of reproductive tract diseases and infertility. CT-Hsp60 is synthesized during infection and is released in the bloodstream. As a consequence, immune cells will produce anti-CT-Hsp60 antibodies. Hsp60, a ubiquitous and evolutionarily conserved chaperonin, is normally sequestered inside the cell, particularly into mitochondria. However, upon cell stress, as well as during carcinogenesis, the chaperonin becomes exposed on the cell surface (sf-Hsp60) and/or is secreted from cells into the extracellular space and circulation. Reports in the literature on circulating Hsp and anti-Hsp antibodies are in many cases short on details about Hsp60 concentrations, and about the specificity spectra of the antibodies, their titers, and their true, direct, pathogenetic effects. Thus, more studies are still needed to obtain a definitive picture on these matters. Nevertheless, the information already available indicates that the concurrence of persistent CT infection and appearance of sf-Hsp60 can promote an autoimmune aggression towards stressed cells and the development of diseases such as autoimmune arthritis, multiple sclerosis, atherosclerosis, vasculitis, diabetes, and thyroiditis, among others. At the same time, immunocomplexes composed of anti-CT-Hsp60 antibodies and circulating Hsp60 (both CT and human) may form deposits in several anatomical locations, e.g., at the glomerular basal membrane. The opposite side of the coin is that pre-tumor and tumor cells with sf-Hsp60 can be destroyed with participation of the anti-Hsp60 antibody, thus stopping cancer progression before it is even noticed by the patient or physician. PMID:19714222

  17. Chlamydia trachomatis infection and anti-Hsp60 immunity: the two sides of the coin.

    Directory of Open Access Journals (Sweden)

    Francesco Cappello

    2009-08-01

    Full Text Available Chlamydia trachomatis (CT infection is one of the most common causes of reproductive tract diseases and infertility. CT-Hsp60 is synthesized during infection and is released in the bloodstream. As a consequence, immune cells will produce anti-CT-Hsp60 antibodies. Hsp60, a ubiquitous and evolutionarily conserved chaperonin, is normally sequestered inside the cell, particularly into mitochondria. However, upon cell stress, as well as during carcinogenesis, the chaperonin becomes exposed on the cell surface (sf-Hsp60 and/or is secreted from cells into the extracellular space and circulation. Reports in the literature on circulating Hsp and anti-Hsp antibodies are in many cases short on details about Hsp60 concentrations, and about the specificity spectra of the antibodies, their titers, and their true, direct, pathogenetic effects. Thus, more studies are still needed to obtain a definitive picture on these matters. Nevertheless, the information already available indicates that the concurrence of persistent CT infection and appearance of sf-Hsp60 can promote an autoimmune aggression towards stressed cells and the development of diseases such as autoimmune arthritis, multiple sclerosis, atherosclerosis, vasculitis, diabetes, and thyroiditis, among others. At the same time, immunocomplexes composed of anti-CT-Hsp60 antibodies and circulating Hsp60 (both CT and human may form deposits in several anatomical locations, e.g., at the glomerular basal membrane. The opposite side of the coin is that pre-tumor and tumor cells with sf-Hsp60 can be destroyed with participation of the anti-Hsp60 antibody, thus stopping cancer progression before it is even noticed by the patient or physician.

  18. Broadening the functionality of a J-protein/Hsp70 molecular chaperone system.

    Science.gov (United States)

    Schilke, Brenda A; Ciesielski, Szymon J; Ziegelhoffer, Thomas; Kamiya, Erina; Tonelli, Marco; Lee, Woonghee; Cornilescu, Gabriel; Hines, Justin K; Markley, John L; Craig, Elizabeth A

    2017-10-01

    By binding to a multitude of polypeptide substrates, Hsp70-based molecular chaperone systems perform a range of cellular functions. All J-protein co-chaperones play the essential role, via action of their J-domains, of stimulating the ATPase activity of Hsp70, thereby stabilizing its interaction with substrate. In addition, J-proteins drive the functional diversity of Hsp70 chaperone systems through action of regions outside their J-domains. Targeting to specific locations within a cellular compartment and binding of specific substrates for delivery to Hsp70 have been identified as modes of J-protein specialization. To better understand J-protein specialization, we concentrated on Saccharomyces cerevisiae SIS1, which encodes an essential J-protein of the cytosol/nucleus. We selected suppressors that allowed cells lacking SIS1 to form colonies. Substitutions changing single residues in Ydj1, a J-protein, which, like Sis1, partners with Hsp70 Ssa1, were isolated. These gain-of-function substitutions were located at the end of the J-domain, suggesting that suppression was connected to interaction with its partner Hsp70, rather than substrate binding or subcellular localization. Reasoning that, if YDJ1 suppressors affect Ssa1 function, substitutions in Hsp70 itself might also be able to overcome the cellular requirement for Sis1, we carried out a selection for SSA1 suppressor mutations. Suppressing substitutions were isolated that altered sites in Ssa1 affecting the cycle of substrate interaction. Together, our results point to a third, additional means by which J-proteins can drive Hsp70's ability to function in a wide range of cellular processes-modulating the Hsp70-substrate interaction cycle.

  19. Determination of the dose index in computerized tomography using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Azorin, J.C.; Calderon, A.; Azorin, J.

    2004-01-01

    In this work the obtained results of the determination of the dose index are presented in thorax studies in computed tomography and helical tomography carried out in Mexico using thermoluminescent dosemeters of LiF: Mg,Cu,P + Ptfe developed and manufactured in our country. The results showed that under similar conditions of irradiation and operation (pitch = 1), significant differences don't exist among the doses absorbed measures in the phantom due to the two types of used tomographs. (Author)

  20. Possibility of the use of PVC plastics as a ray dosemeter

    International Nuclear Information System (INIS)

    Amri Ayat; Sutrisno Puspodikoro.

    1978-01-01

    The use of plastics as a radiation dosemeter for measurement of γ-rays is very attractive to be studied. In the work presented here commercial PVC film with the trade-mark ''Takiron'' is used for Co-60 radiation dosimetry. According to the experiments the useful dose range extends over 0.15-1.2 Mrads. Fading of the coloration with time after radiation exposure can be stabilised by heat treatment (60 deg C for 30 minutes). (author)

  1. A role for anti-HSP60 antibodies in arthritis

    DEFF Research Database (Denmark)

    Carlsen, Thomas Gelsing; Bennike, Tue; Christiansen, Gunna

    2013-01-01

    As a result of the high sequence similarity between HSP60 proteins, found in both prokaryotic and eukaryotic cells, it has been suggested, but never concluded, that anti-HSP60 antibodies could be of importance in the pathology of arthritis diseases explained by a concept named molecular mimicry...

  2. Molecular mechanism of bacterial Hsp90 pH-dependent ATPase activity.

    Science.gov (United States)

    Jin, Yi; Hoxie, Reyal S; Street, Timothy O

    2017-06-01

    Hsp90 is a dimeric molecular chaperone that undergoes an essential and highly regulated open-to-closed-to-open conformational cycle upon ATP binding and hydrolysis. Although it has been established that a large energy barrier to closure is responsible for Hsp90's low ATP hydrolysis rate, the specific molecular contacts that create this energy barrier are not known. Here we discover that bacterial Hsp90 (HtpG) has a pH-dependent ATPase activity that is unique among other Hsp90 homologs. The underlying mechanism is a conformation-specific electrostatic interaction between a single histidine, H255, and bound ATP. H255 stabilizes ATP only while HtpG adopts a catalytically inactive open configuration, resulting in a striking anti-correlation between nucleotide binding affinity and chaperone activity over a wide range of pH. Linkage analysis reveals that the H255-ATP salt bridge contributes 1.5 kcal/mol to the energy barrier of closure. This energetic contribution is structurally asymmetric, whereby only one H255-ATP salt-bridge per dimer of HtpG controls ATPase activation. We find that a similar electrostatic mechanism regulates the ATPase of the endoplasmic reticulum Hsp90, and that pH-dependent activity can be engineered into eukaryotic cytosolic Hsp90. These results reveal site-specific energetic information about an evolutionarily conserved conformational landscape that controls Hsp90 ATPase activity. © 2017 The Protein Society.

  3. Design and validation of a single sphere multi-detector neutron spectrometer based on LiF: Mg,Cu,P thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Gomez-Ros, Jose Maria; Bedogni, Roberto; Moraleda, Montserrat; Romero, Ana; Delgado, Antonio; Esposito, Adolfo

    2010-01-01

    This communication describes a new neutron spectrometer consisting of pairs of 7 Li and 6 Li based thermoluminescent dosemeters (MCP-6, MCP-7) located at selected positions within a single moderating polyethylene sphere. The spatial arrangement of the dosemeters has been designed using the MCNPX Monte Carlo code to calculate the response matrix in order to obtain a nearly isotropic response for neutrons in the energy range up to 20 MeV. A partial validation of the calculated response matrix has been performed with the calibrated 241 Am-Be neutron source at the INFN-LNF Laboratory, using the shadow cone technique.

  4. Dissolution behaviour of 238U, 234U and 230Th deposited on filters from personal dosemeters

    International Nuclear Information System (INIS)

    Beckova, V.; Malatova, I.

    2008-01-01

    Kinetics of dissolution of 238 U, 234 U and 230 Th dust deposited on filters from personal alpha dosemeters was studied by means of a 26-d in vitro dissolution test with a serum ultra-filtrate simulant. Dosemeters had been used by miners at the uranium mine 'Dolni Rozinka' at Rozna, Czech Republic. The sampling flow-rate as declared by the producer is 4 l h -1 and the sampling period is typically 1 month. Studied filters contained 125 ± 6 mBq 238 U in equilibrium with 234 U and 230 Th; no 232 Th series nuclides were found. Half-time of rapid dissolution of 1.4 d for 238 U and 234 U and slow dissolution half-times of 173 and 116 d were found for 238 U and 234 U, respectively. No detectable dissolution of 230 Th was found. (authors)

  5. Adenoviral transfer of HSP-70 into pulmonary epithelium ameliorates experimental acute respiratory distress syndrome.

    Science.gov (United States)

    Weiss, Yoram G; Maloyan, Alina; Tazelaar, John; Raj, Nichelle; Deutschman, Clifford S

    2002-09-01

    The acute respiratory distress syndrome (ARDS) provokes three pathologic processes: unchecked inflammation, interstitial/alveolar protein accumulation, and destruction of pulmonary epithelial cells. The highly conserved heat shock protein HSP-70 can limit all three responses but is not appropriately expressed in the lungs after cecal ligation and double puncture (2CLP), a clinically relevant model of ARDS. We hypothesize that restoring expression of HSP-70 using adenovirus-mediated gene therapy will limit pulmonary pathology following 2CLP. We administered a vector containing the porcine HSP-70 cDNA driven by a CMV promoter (AdHSP) into the lungs of rats subjected to 2CLP or sham operation. Administration of AdHSP after either sham operation or 2CLP increased HSP-70 protein expression in lung tissue, as determined by immunohistochemistry and Western blot hybridization. Administration of AdHSP significantly attenuated interstitial and alveolar edema and protein exudation and dramatically decreased neutrophil accumulation, relative to a control adenovirus. CLP-associated mortality at 48 hours was reduced by half. Modulation of HSP-70 production reduces pathologic changes and may improve outcome in experimental ARDS.

  6. Silencing of Hsp27 and Hsp72 in glioma cells as a tool for programmed cell death induction upon temozolomide and quercetin treatment

    Energy Technology Data Exchange (ETDEWEB)

    Jakubowicz-Gil, Joanna, E-mail: jjgil@poczta.umcs.lublin.pl [Department of Comparative Anatomy and Anthropology, Maria Curie-Sklodowska University, Akademicka 19, 20-033 Lublin (Poland); Langner, Ewa [Department of Medical Biology, Institute of Agricultural Medicine, Jaczewskiego 2, 20-950 Lublin (Poland); Bądziul, Dorota [Department of Comparative Anatomy and Anthropology, Maria Curie-Sklodowska University, Akademicka 19, 20-033 Lublin (Poland); Wertel, Iwona [1st Department of Gynaecology, University School of Medicine, Staszica 16, 20-081 Lublin (Poland); Rzeski, Wojciech [Department of Medical Biology, Institute of Agricultural Medicine, Jaczewskiego 2, 20-950 Lublin (Poland); Department of Immunology and Virology, Maria Curie-Sklodowska University, Akademicka 19, 20-033 Lublin (Poland)

    2013-12-15

    The aim of the present study was to investigate whether silencing of Hsp27 or Hsp72 expression in glioblastoma multiforme T98G and anaplastic astrocytoma MOGGCCM cells increases their sensitivity to programmed cell death induction upon temozolomide and/or quercetin treatment. Transfection with specific siRNA was performed for the Hsp gene silencing. As revealed by microscopic observation and flow cytometry, the inhibition of Hsp expression was correlated with severe apoptosis induction upon the drug treatment studied. No signs of autophagy were detected. This was correlated with a decreased mitochondrial membrane potential, increased level of cytochrome c in the cytoplasm, and activation of caspase 3 and caspase 9. All these results suggest that the apoptotic signal was mediated by an internal pathway. Additionally, in a large percentage of cells treated with temozolomide, with or without quercetin, granules within the ER system were found, which was accompanied by an increased level of caspase 12 expression. This might be correlated with ER stress. Quercetin and temozolomide also changed the shape of nuclei from circular to “croissant like” in both transfected cell lines. Our results indicate that blocking of Hsp27 and Hsp72 expression makes T98G cells and MOGGCCM cells extremely vulnerable to apoptosis induction upon temozolomide and quercetin treatment and that programmed cell death is initiated by an internal signal. - Highlights: • Hsps gene silencing induced severe apoptosis upon temozolomide–quercetin treatment • Apoptosis in transfected glioma cells was initiated by internal signal • Programmed cell death was preceded by ER stress • Temozolomide–quercetin treatment changed nuclei shape in transfected glioma cells.

  7. Radiofrequency detection by bubble dosemeter technology

    International Nuclear Information System (INIS)

    Olsen, R.G.

    1990-01-01

    In an initial attempt to utilise solid state dosimetric technology for non-ionizing radiation, planar bubble type detectors were irradiated with microwave energy at 2.38 GHz. Individual devices were produced as thin discs (8 cm diam. x 0.6 cm) rather than in the normal test-tube configuration. Both aqueous and non-aqueous-based devices were exposed to plane-wave irradiation inside a microwave anechoic chamber at power densities ranging from 40 to 80 mW.cm -2 . Specific absorption rate (SAR) in the disc shaped devices was thermometrically determined with the aid of a non-perturbing temperature probe and was approximately 0.3 (W.kg -1 )(mW.cm -2 ). Results showed the irradiation-induced bubble response to be relatively uniform in both types of devices, but the sensitivity was lower than that needed in a practical microwave dosemeter. We believe that improved sensitivity will be obtained by adding materials with a high microwave absorption cross section. (author)

  8. Hsp27, Hsp70, and metallothionein in MDCK and LLC-PK1 renal epithelial cells: effects of prolonged exposure to cadmium

    International Nuclear Information System (INIS)

    Bonham, Rita T.; Fine, Michael R.; Pollock, Fiona M.; Shelden, Eric A.

    2003-01-01

    Cadmium is a widely distributed industrial and environmental toxin. The principal target organ of chronic sublethal cadmium exposure is the kidney. In renal epithelial cells, acute high-dose cadmium exposure induces differential expression of proteins, including heat shock proteins. However, few studies have examined heat shock protein expression in cells after prolonged exposure to cadmium at sublethal concentrations. Here, we assayed total cell protein, neutral red uptake, cell death, and levels of metallothionein and heat shock proteins Hsp27 and inducible Hsp70 in cultures of MDCK and LLC-PK1 renal epithelial cells treated with cadmium for 3 days. Treatment with cadmium at concentrations equal to or greater than 10 μM (LLC-PK1) or 25 μM (MDCK) reduced measures of cell vitality and induced cell death. However, a concentration-dependent increase in Hsp27 was detected in both cell types treated with as little as 5 μM cadmium. Accumulation of Hsp70 was correlated only with cadmium treatment at concentrations also causing cell death. Metallothionein was maximally detected in cells treated with cadmium at concentrations that did not reduce cell vitality, and further increases were not detected at greater concentrations. These results reveal that heat shock proteins accumulate in renal epithelial cells during prolonged cadmium exposure, that cadmium induces differential expression of heat shock protein in epithelial cells, and that protein expression patterns in epithelial cells are specific to the cadmium concentration and degree of cellular injury. A potential role for Hsp27 in the cellular response to sublethal cadmium-induced injury is also implicated by our results

  9. The Double-Edged Sword: Conserved Functions of Extracellular Hsp90 in Wound Healing and Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hance, Michael W.; Nolan, Krystal D.; Isaacs, Jennifer S., E-mail: isaacsj@musc.edu [Department of Cell and Molecular Pharmacology, Medical University of South Carolina, Hollings Cancer Center, Charleston, SC 29412 (United States)

    2014-05-06

    Heat shock proteins (Hsps) represent a diverse group of chaperones that play a vital role in the protection of cells against numerous environmental stresses. Although our understanding of chaperone biology has deepened over the last decade, the “atypical” extracellular functions of Hsps have remained somewhat enigmatic and comparatively understudied. The heat shock protein 90 (Hsp90) chaperone is a prototypic model for an Hsp family member exhibiting a duality of intracellular and extracellular functions. Intracellular Hsp90 is best known as a master regulator of protein folding. Cancers are particularly adept at exploiting this function of Hsp90, providing the impetus for the robust clinical development of small molecule Hsp90 inhibitors. However, in addition to its maintenance of protein homeostasis, Hsp90 has also been identified as an extracellular protein. Although early reports ascribed immunoregulatory functions to extracellular Hsp90 (eHsp90), recent studies have illuminated expanded functions for eHsp90 in wound healing and cancer. While the intended physiological role of eHsp90 remains enigmatic, its evolutionarily conserved functions in wound healing are easily co-opted during malignancy, a pathology sharing many properties of wounded tissue. This review will highlight the emerging functions of eHsp90 and shed light on its seemingly dichotomous roles as a benevolent facilitator of wound healing and as a sinister effector of tumor progression.

  10. Calcium Homeostasis and Muscle Energy Metabolism Are Modified in HspB1-Null Mice

    Directory of Open Access Journals (Sweden)

    Brigitte Picard

    2016-05-01

    Full Text Available Hsp27—encoded by HspB1—is a member of the small heat shock proteins (sHsp, 12–43 kDa (kilodalton family. This protein is constitutively present in a wide variety of tissues and in many cell lines. The abundance of Hsp27 is highest in skeletal muscle, indicating a crucial role for muscle physiology. The protein identified as a beef tenderness biomarker was found at a crucial hub in a functional network involved in beef tenderness. The aim of this study was to analyze the proteins impacted by the targeted invalidation of HspB1 in the Tibialis anterior muscle of the mouse. Comparative proteomics using two-dimensional gel electrophoresis revealed 22 spots that were differentially abundant between HspB1-null mice and their controls that could be identified by mass spectrometry. Eighteen spots were more abundant in the muscle of the mutant mice, and four were less abundant. The proteins impacted by the absence of Hsp27 belonged mainly to calcium homeostasis (Srl and Calsq1, contraction (TnnT3, energy metabolism (Tpi1, Mdh1, PdhB, Ckm, Pygm, ApoA1 and the Hsp proteins family (HspA9. These data suggest a crucial role for these proteins in meat tenderization. The information gained by this study could also be helpful to predict the side effects of Hsp27 depletion in muscle development and pathologies linked to small Hsps.

  11. Influence of different types of phantoms on the calibration of dosemeters for eye lens dosimetry

    International Nuclear Information System (INIS)

    Yoshitomi, H.; Kowatari, M.

    2016-01-01

    Both a cylinder and a slab phantom have been recommended to be used as calibration phantoms for eye lens dosimetry in the International Atomic Energy Agency TECDOC. This study describes investigations on the influence of the type of phantom on the calibration of dosemeters. In order to fulfil the purpose, backscatter radiation from practically used water-filled phantoms was evaluated by calculations and experiments. For photons, the calculations showed that the cylinder phantom had 10 % lower backscattered effect at maximum than a slab phantom, and simulated well the backscattered effect of the human head or neck to within ±10 %. The irradiation results of non-filtered optically stimulated luminescence and radio-photoluminescence glass dosemeters indicated that the differences of the calibration factors between the two types of phantoms were up to 20 and 10 %, respectively, reflecting the response to backscattered photons. For electrons, no difference was found between the two types of phantoms. (authors)

  12. Administration of Mycobacterium leprae rHsp65 aggravates experimental autoimmune uveitis in mice.

    Directory of Open Access Journals (Sweden)

    Eliana B Marengo

    Full Text Available The 60 kDa heat shock protein family, Hsp60, constitutes an abundant and highly conserved class of molecules that are highly expressed in chronic-inflammatory and autoimmune processes. Experimental autoimmune uveitis [EAU] is a T cell mediated intraocular inflammatory disease that resembles human uveitis. Mycobacterial and homologous Hsp60 peptides induces uveitis in rats, however their participation in aggravating the disease is poorly known. We here evaluate the effects of the Mycobacterium leprae Hsp65 in the development/progression of EAU and the autoimmune response against the eye through the induction of the endogenous disequilibrium by enhancing the entropy of the immunobiological system with the addition of homologous Hsp. B10.RIII mice were immunized subcutaneously with interphotoreceptor retinoid-binding protein [IRBP], followed by intraperitoneally inoculation of M. leprae recombinant Hsp65 [rHsp65]. We evaluated the proliferative response, cytokine production and the percentage of CD4(+IL-17(+, CD4(+IFN-gamma(+ and CD4(+Foxp3(+ cells ex vivo, by flow cytometry. Disease severity was determined by eye histological examination and serum levels of anti-IRBP and anti-Hsp60/65 measured by ELISA. EAU scores increased in the Hsp65 group and were associated with an expansion of CD4(+IFN-gamma(+ and CD4(+IL-17(+ T cells, corroborating with higher levels of IFN-gamma. Our data indicate that rHsp65 is one of the managers with a significant impact over the immune response during autoimmunity, skewing it to a pathogenic state, promoting both Th1 and Th17 commitment. It seems comprehensible that the specificity and primary function of Hsp60 molecules can be considered as a potential pathogenic factor acting as a whistleblower announcing chronic-inflammatory diseases progression.

  13. Increased radiosensitivity and radiothermosensitivity of human pancreatic MIA PaCa-2 and U251 glioblastoma cell lines treated with the novel Hsp90 inhibitor NVP-HSP990

    International Nuclear Information System (INIS)

    Milanović, Dušan; Firat, Elke; Grosu, Anca Ligia; Niedermann, Gabriele

    2013-01-01

    Heat shock Protein 90 (Hsp90) is a molecular chaperone that folds, stabilizes, and functionally regulates many cellular proteins involved in oncogenic signaling and in the regulation of radiosensitivity. It is upregulated in response to stress such a heat. Hyperthermia is a potent radiosensitizer, but induction of Hsp90 may potentially limit its efficacy. Our aim was to investigate whether the new Hsp90 inhibitor NVP-HSP990 increases radiosensitivity, thermosensitivity and radiothermosensitivity of human tumor cell lines. U251 glioblastoma and MIA PaCa-2 pancreatic carcinoma cells were used. To determine clonogenic survival, colony forming assays were performed. Cell viability and proliferation were assesed by Trypan blue staining. Cell cycle and apoptosis analyses were performed by flow cytometry. DAPI staining was used to detect mitotic catastrophe. NVP-HSP990 increased the thermosensitivity, radiosensitivity and radio-thermosensitivity of both cell lines in clonogenic assays. 72 hours after irradiation with 4 Gy, a significant reduction in cell number associated with considerable G2/M acumulation and mitotic catastrophe as well as cell death by apoptosis/necrosis was observed. Treatment with NVP-HSP990 strongly sensitized U251 and MIA PaCa-2 cells to hyperthermia and ionizing radiation or combination thereof through augmentation of G2/M arrest, mitotic catastrophe and associated apoptosis

  14. Hsp70/J-protein machinery from Glossina morsitans morsitans, vector of African trypanosomiasis.

    Directory of Open Access Journals (Sweden)

    Stephen J Bentley

    Full Text Available Tsetse flies (Glossina spp. are the sole vectors of the protozoan parasites of the genus Trypanosoma, the causative agents of African Trypanosomiasis. Species of Glossina differ in vector competence and Glossina morsitans morsitans is associated with transmission of Trypanosoma brucei rhodesiense, which causes an acute and often fatal form of African Trypanosomiasis. Heat shock proteins are evolutionarily conserved proteins that play critical roles in proteostasis. The activity of heat shock protein 70 (Hsp70 is regulated by interactions with its J-protein (Hsp40 co-chaperones. Inhibition of these interactions are emerging as potential therapeutic targets. The assembly and annotation of the G. m. morsitans genome provided a platform to identify and characterize the Hsp70s and J-proteins, and carry out an evolutionary comparison to its well-studied eukaryotic counterparts, Drosophila melanogaster and Homo sapiens, as well as Stomoxys calcitrans, a comparator species. In our study, we identified 9 putative Hsp70 proteins and 37 putative J-proteins in G. m. morsitans. Phylogenetic analyses revealed three evolutionarily distinct groups of Hsp70s, with a closer relationship to orthologues from its blood-feeding dipteran relative Stomoxys calcitrans. G. m. morsitans also lacked the high number of heat inducible Hsp70s found in D. melanogaster. The potential localisations, functions, domain organisations and Hsp70/J-protein partnerships were also identified. A greater understanding of the heat shock 70 (Hsp70 and J-protein (Hsp40 families in G. m. morsitans could enhance our understanding of the cell biology of the tsetse fly.

  15. Hsp90 and hepatobiliary transformation during sea lamprey metamorphosis.

    Science.gov (United States)

    Chung-Davidson, Yu-Wen; Yeh, Chu-Yin; Bussy, Ugo; Li, Ke; Davidson, Peter J; Nanlohy, Kaben G; Brown, C Titus; Whyard, Steven; Li, Weiming

    2015-12-01

    Biliary atresia (BA) is a human infant disease with inflammatory fibrous obstructions in the bile ducts and is the most common cause for pediatric liver transplantation. In contrast, the sea lamprey undergoes developmental BA with transient cholestasis and fibrosis during metamorphosis, but emerges as a fecund adult. Therefore, sea lamprey liver metamorphosis may serve as an etiological model for human BA and provide pivotal information for hepatobiliary transformation and possible therapeutics. We hypothesized that liver metamorphosis in sea lamprey is due to transcriptional reprogramming that dictates cellular remodeling during metamorphosis. We determined global gene expressions in liver at several metamorphic landmark stages by integrating mRNA-Seq and gene ontology analyses, and validated the results with real-time quantitative PCR, histological and immunohistochemical staining. These analyses revealed that gene expressions of protein folding chaperones, membrane transporters and extracellular matrices were altered and shifted during liver metamorphosis. HSP90, important in protein folding and invertebrate metamorphosis, was identified as a candidate key factor during liver metamorphosis in sea lamprey. Blocking HSP90 with geldanamycin facilitated liver metamorphosis and decreased the gene expressions of the rate limiting enzyme for cholesterol biosynthesis, HMGCoA reductase (hmgcr), and bile acid biosynthesis, cyp7a1. Injection of hsp90 siRNA for 4 days altered gene expressions of met, hmgcr, cyp27a1, and slc10a1. Bile acid concentrations were increased while bile duct and gall bladder degeneration was facilitated and synchronized after hsp90 siRNA injection. HSP90 appears to play crucial roles in hepatobiliary transformation during sea lamprey metamorphosis. Sea lamprey is a useful animal model to study postembryonic development and mechanisms for hsp90-induced hepatobiliary transformation.

  16. Monocyte Proteomics Reveals Involvement of Phosphorylated HSP27 in the Pathogenesis of Osteoporosis

    Directory of Open Access Journals (Sweden)

    Bhavna Daswani

    2015-01-01

    Full Text Available Peripheral monocytes, precursors of osteoclasts, have emerged as important candidates for identifying proteins relevant to osteoporosis, a condition characterized by low Bone Mineral Density (BMD and increased susceptibility for fractures. We employed 4-plex iTRAQ (isobaric tags for relative and absolute quantification coupled with LC-MS/MS (liquid chromatography coupled with tandem mass spectrometry to identify differentially expressed monocyte proteins from premenopausal and postmenopausal women with low versus high BMD. Of 1801 proteins identified, 45 were differentially abundant in low versus high BMD, with heat shock protein 27 (HSP27 distinctly upregulated in low BMD condition in both premenopausal and postmenopausal categories. Validation in individual samples (n=80 using intracellular ELISA confirmed that total HSP27 (tHSP27 as well as phosphorylated HSP27 (pHSP27 was elevated in low BMD condition in both categories (P<0.05. Further, using transwell assays, pHSP27, when placed in the upper chamber, could increase monocyte migration (P<0.0001 and this was additive in combination with RANKL (receptor activator of NFkB ligand placed in the lower chamber (P=0.05. Effect of pHSP27 in monocyte migration towards bone milieu can result in increased osteoclast formation and thus contribute to pathogenesis of osteoporosis. Overall, this study reveals for the first time a novel link between monocyte HSP27 and BMD.

  17. Spectral correction factors for conventional neutron dosemeters used in high-energy neutron environments

    International Nuclear Information System (INIS)

    Lee, K.W.; Sheu, R.J.

    2015-01-01

    High-energy neutrons (>10 MeV) contribute substantially to the dose fraction but result in only a small or negligible response in most conventional moderated-type neutron detectors. Neutron dosemeters used for radiation protection purpose are commonly calibrated with 252 Cf neutron sources and are used in various workplace. A workplace-specific correction factor is suggested. In this study, the effect of the neutron spectrum on the accuracy of dose measurements was investigated. A set of neutron spectra representing various neutron environments was selected to study the dose responses of a series of Bonner spheres, including standard and extended-range spheres. By comparing 252 Cf-calibrated dose responses with reference values based on fluence-to-dose conversion coefficients, this paper presents recommendations for neutron field characterisation and appropriate correction factors for responses of conventional neutron dosemeters used in environments with high-energy neutrons. The correction depends on the estimated percentage of high-energy neutrons in the spectrum or the ratio between the measured responses of two Bonner spheres (the 4P6-8 extended-range sphere versus the 6'' standard sphere). (authors)

  18. Hsp70 in the atrial neuroendocrine units of the snail, Achatina fulica.

    Science.gov (United States)

    Martynova, M G; Bystrova, O A; Shabelnikov, S V; Margulis, B A; Prokofjeva, D S

    2007-04-01

    Heat shock proteins (Hsps) are evolutionary conserved peptides well known as molecular chaperones and stress proteins. Elevated levels of extracellular Hsps in blood plasma have been observed during the stress responses and some diseases. Information on the cellular sources of extracellular Hsps and mechanisms regulating their release is still scanty. Here we showed the presence and localization of Hsp70 in the neuroendocrine system in the atrium of the snail, Achatina fulica. The occurrence of the peptide in snail atrium lysate was detected by Western blot analysis. Immunoperoxidase and immunogold staining demonstrated that Hsp70-immunoreactivity is mainly confined to the peculiar atrial neuroendocrine units which are formed by nerve fibers tightly contacted with large granular cells. Immunolabelling intensity differed in morphologically distinct types of secretory granules in the granular cells. The pictures of exocytosis of Hsp70-immunolabeled granules from the granular cells were observed. In nerve bundles, axon profiles with Hsp70-immunoreactive and those with non-immunoreactive neurosecretory granules were found. In addition, Hsp70-like material was also revealed in the granules of glia-interstitial cells that accompanied nerve fibers. Our findings provide an immuno-morphological basis for a role of Hsp70 in the functioning of the neuroendocrine system in the snail heart, and show that the atrial granular cells are a probable source of extracellular Hsp70 in the snail hemolymph.

  19. HSP10 selective preference for myeloid and megakaryocytic precursors in normal human bone marrow

    Directory of Open Access Journals (Sweden)

    F Cappello

    2009-06-01

    Full Text Available Heat shock proteins (HSPs constitute a heterogeneous family of proteins involved in cell homeostasis. During cell life they are involved in harmful insults, as well as in immune and inflammatory reactions. It is known that they regulate gene expression, and cell proliferation, differentiation and death. HSP60 is a mitochondrial chaperonin, highly preserved during evolution, responsible of protein folding. Its function is strictly dependent on HSP10 in both prokaryotic and eukaryotic elements. We investigated the presence and the expression of HSP60 and HSP10 in a series of 20 normal human bone marrow specimens (NHBM by the means of immunohistochemistry. NHBM showed no expression of HSP60, probably due to its being below the detectable threshold, as already demonstrated in other normal human tissues. By contrast, HSP10 showed a selective positivity for myeloid and megakaryocytic lineages. The positivity was restricted to precursor cells, while mature elements were constantly negative.We postulate that HSP10 plays a role in bone marrow cell differentiation other than being a mitochondrial co-chaperonin. The present data emphasize the role of HSP10 during cellular homeostasis and encourage further investigations in this field.

  20. Differences in the curing of [PSI+] prion by various methods of Hsp104 inactivation.

    Directory of Open Access Journals (Sweden)

    Yang-Nim Park

    Full Text Available [PSI(+] yeast, containing the misfolded amyloid conformation of Sup35 prion, is cured by inactivation of Hsp104. There has been controversy as to whether inactivation of Hsp104 by guanidine treatment or by overexpression of the dominant negative Hsp104 mutant, Hsp104-2KT, cures [PSI(+] by the same mechanism- inhibition of the severing of the prion seeds. Using live cell imaging of Sup35-GFP, overexpression of Hsp104-2KT caused the foci to increase in size, then decrease in number, and finally disappear when the cells were cured, similar to that observed in cells cured by depletion of Hsp104. In contrast, guanidine initially caused an increase in foci size but then the foci disappeared before the cells were cured. By starving the yeast to make the foci visible in cells grown with guanidine, the number of cells with foci was found to correlate exactly with the number of [PSI(+] cells, regardless of the curing method. Therefore, the fluorescent foci are the prion seeds required for maintenance of [PSI(+] and inactivation of Hsp104 cures [PSI(+] by preventing severing of the prion seeds. During curing with guanidine, the reduction in seed size is an Hsp104-dependent effect that cannot be explained by limited severing of the seeds. Instead, in the presence of guanidine, Hsp104 retains an activity that trims or reduces the size of the prion seeds by releasing Sup35 molecules that are unable to form new prion seeds. This Hsp104 activity may also occur in propagating yeast.

  1. The evolutionary capacitor HSP90 buffers the regulatory effects of mammalian endogenous retroviruses.

    Science.gov (United States)

    Hummel, Barbara; Hansen, Erik C; Yoveva, Aneliya; Aprile-Garcia, Fernando; Hussong, Rebecca; Sawarkar, Ritwick

    2017-03-01

    Understanding how genotypes are linked to phenotypes is important in biomedical and evolutionary studies. The chaperone heat-shock protein 90 (HSP90) buffers genetic variation by stabilizing proteins with variant sequences, thereby uncoupling phenotypes from genotypes. Here we report an unexpected role of HSP90 in buffering cis-regulatory variation affecting gene expression. By using the tripartite-motif-containing 28 (TRIM28; also known as KAP1)-mediated epigenetic pathway, HSP90 represses the regulatory influence of endogenous retroviruses (ERVs) on neighboring genes that are critical for mouse development. Our data based on natural variations in the mouse genome show that genes respond to HSP90 inhibition in a manner dependent on their genomic location with regard to strain-specific ERV-insertion sites. The evolutionary-capacitor function of HSP90 may thus have facilitated the exaptation of ERVs as key modifiers of gene expression and morphological diversification. Our findings add a new regulatory layer through which HSP90 uncouples phenotypic outcomes from individual genotypes.

  2. Production and Purification of the Native Saccharomyces cerevisiae Hsp12 in Escherichia coli.

    Science.gov (United States)

    Léger, Antoine; Hocquellet, Agnès; Dieryck, Wilfrid; Moine, Virginie; Marchal, Axel; Marullo, Philippe; Josseaume, Annabelle; Cabanne, Charlotte

    2017-09-20

    Hsp12 is a small heat shock protein produced in many organisms, including the yeast Saccharomyces cerevisiae. It has been described as an indicator of yeast stress rate and has also been linked to the sweetness sensation of wine. To obtain a sufficient amount of protein, we produced and purified Hsp12 without tag in Escherichia coli. A simple fast two-step process was developed using a microplate approach and a design of experiments. A capture step on an anion-exchange salt-tolerant resin was followed by size exclusion chromatography for polishing, leading to a purity of 97%. Thereafter, specific anti-Hsp12 antibodies were obtained by rabbit immunization. An ELISA was developed to quantify Hsp12 in various strains of Saccharomyces cerevisiae. The antibodies showed high specificity and allowed the quantitation of Hsp12 in the yeast. The quantities of Hsp12 measured in the strains differed in direct proportion to the level of expression found in previous studies.

  3. Dissolution behaviour of 238U, 234U and 230Th deposited on filters from personal dosemeters.

    Science.gov (United States)

    Becková, Vera; Malátová, Irena

    2008-01-01

    Kinetics of dissolution of (238)U, (234)U and (230)Th dust deposited on filters from personal alpha dosemeters was studied by means of a 26-d in vitro dissolution test with a serum ultrafiltrate simulant. Dosemeters had been used by miners at the uranium mine 'Dolní Rozínka' at Rozná, Czech Republic. The sampling flow-rate as declared by the producer is 4 l h(-1) and the sampling period is typically 1 month. Studied filters contained 125 +/- 6 mBq (238)U in equilibrium with (234)U and (230)Th; no (232)Th series nuclides were found. Half-time of rapid dissolution of 1.4 d for (238)U and (234)U and slow dissolution half-times of 173 and 116 d were found for (238)U and (234)U, respectively. No detectable dissolution of (230)Th was found.

  4. Identification of HSP90 gene from the Chinese oak silkworm ...

    African Journals Online (AJOL)

    ajl user 1

    2012-06-28

    Jun 28, 2012 ... College of Life Science, Anhui Agricultural University, 130 Changjiang West Road 230036, Peoples ... program consisted of 5 min at 94°C followed by 35 cycles of 94°C ... HSP90 and 73.1% identity with Bombyx mori HSP90.

  5. Tah1 helix-swap dimerization prevents mixed Hsp90 co-chaperone complexes

    International Nuclear Information System (INIS)

    Morgan, Rhodri M. L.; Pal, Mohinder; Roe, S. Mark; Pearl, Laurence H.; Prodromou, Chrisostomos

    2015-01-01

    A helix swap involving the fifth helix between two adjacently bound Tah1 molecules restores the normal binding environment of the conserved MEEVD peptide of Hsp90. Dimerization also explains how other monomeric TPR-domain proteins are excluded from forming inappropriate mixed co-chaperone complexes with Hsp90 and Tah1. Specific co-chaperone adaptors facilitate the recruitment of client proteins to the Hsp90 system. Tah1 binds the C-terminal conserved MEEVD motif of Hsp90, thus linking an eclectic set of client proteins to the R2TP complex for their assembly and regulation by Hsp90. Rather than the normal complement of seven α-helices seen in other tetratricopeptide repeat (TPR) domains, Tah1 unusually consists of the first five only. Consequently, the methionine of the MEEVD peptide remains exposed to solvent when bound by Tah1. In solution Tah1 appears to be predominantly monomeric, and recent structures have failed to explain how Tah1 appears to prevent the formation of mixed TPR domain-containing complexes such as Cpr6–(Hsp90) 2 –Tah1. To understand this further, the crystal structure of Tah1 in complex with the MEEVD peptide of Hsp90 was determined, which shows a helix swap involving the fifth α-helix between two adjacently bound Tah1 molecules. Dimerization of Tah1 restores the normal binding environment of the bound Hsp90 methionine residue by reconstituting a TPR binding site similar to that in seven-helix-containing TPR domain proteins. Dimerization also explains how other monomeric TPR-domain proteins are excluded from forming inappropriate mixed co-chaperone complexes

  6. Tah1 helix-swap dimerization prevents mixed Hsp90 co-chaperone complexes

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Rhodri M. L.; Pal, Mohinder; Roe, S. Mark; Pearl, Laurence H., E-mail: laurence.pearl@sussex.ac.uk; Prodromou, Chrisostomos, E-mail: laurence.pearl@sussex.ac.uk [University of Sussex, Falmer, Brighton BN1 9RQ (United Kingdom)

    2015-05-01

    A helix swap involving the fifth helix between two adjacently bound Tah1 molecules restores the normal binding environment of the conserved MEEVD peptide of Hsp90. Dimerization also explains how other monomeric TPR-domain proteins are excluded from forming inappropriate mixed co-chaperone complexes with Hsp90 and Tah1. Specific co-chaperone adaptors facilitate the recruitment of client proteins to the Hsp90 system. Tah1 binds the C-terminal conserved MEEVD motif of Hsp90, thus linking an eclectic set of client proteins to the R2TP complex for their assembly and regulation by Hsp90. Rather than the normal complement of seven α-helices seen in other tetratricopeptide repeat (TPR) domains, Tah1 unusually consists of the first five only. Consequently, the methionine of the MEEVD peptide remains exposed to solvent when bound by Tah1. In solution Tah1 appears to be predominantly monomeric, and recent structures have failed to explain how Tah1 appears to prevent the formation of mixed TPR domain-containing complexes such as Cpr6–(Hsp90){sub 2}–Tah1. To understand this further, the crystal structure of Tah1 in complex with the MEEVD peptide of Hsp90 was determined, which shows a helix swap involving the fifth α-helix between two adjacently bound Tah1 molecules. Dimerization of Tah1 restores the normal binding environment of the bound Hsp90 methionine residue by reconstituting a TPR binding site similar to that in seven-helix-containing TPR domain proteins. Dimerization also explains how other monomeric TPR-domain proteins are excluded from forming inappropriate mixed co-chaperone complexes.

  7. TL response of LiF: Mg, Cu, P dosemeters in function of the photon energy; Respuesta TL de dosimetros de LiF: Mg, Cu, P en funcion de la energia del foton

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, P.R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico); Furetta, C. [Universita degli Studi di Roma ' La Sapienza' , Piazzale Aldo Moro 2, 00185 Roma (Italy)

    2005-07-01

    In this work the obtained results of studying the response of dosemeters of LiF: Mg, Cu, P + Ptfe, developed in the ININ, commercial dosemeters GR200A (LiF: Mg, Cu, P) of chinese manufacture and TLD-100 (LiF: Mg, Ti) US are presented, when irradiating them with X rays 16, 24, 34.5, 42, 100 and 145 keV of effective energy, with gamma rays of 662 keV ({sup 137} Cs) and 1252 keV ({sup 60} Co). The results are presented in function of the sensitivity that the dosemeters showed normalized to gamma radiation of {sup 60} Co. It was appreciated that the dosemeters more equivalent to the tissue, they were those of LiF: Mg, Cu, P + Ptfe, while the less equivalent ones were the TLD-100. (Author)

  8. secHsp70 as a tool to approach amyloid-β42 and other extracellular amyloids.

    Science.gov (United States)

    De Mena, Lorena; Chhangani, Deepak; Fernandez-Funez, Pedro; Rincon-Limas, Diego E

    2017-07-03

    Self-association of amyloidogenic proteins is the main pathological trigger in a wide variety of neurodegenerative disorders. These aggregates are deposited inside or outside the cell due to hereditary mutations, environmental exposures or even normal aging. Cumulative evidence indicates that the heat shock chaperone Hsp70 possesses robust neuroprotection against various intracellular amyloids in Drosophila and mouse models. However, its protective role against extracellular amyloids was largely unknown as its presence outside the cells is very limited. Our recent manuscript in PNAS revealed that an engineered form of secreted Hsp70 (secHsp70) is highly protective against toxicity induced by extracellular deposition of the amyloid-β42 (Aβ42) peptide. In this Extra View article, we extend our analysis to other members of the heat shock protein family. We created PhiC31-based transgenic lines for human Hsp27, Hsp40, Hsp60 and Hsp70 and compared their activities in parallel against extracellular Aβ42. Strikingly, only secreted Hsp70 exhibits robust protection against Aβ42-triggered toxicity in the extracellular milieu. These observations indicate that the ability of secHsp70 to suppress Aβ42 insults is quite unique and suggest that targeted secretion of Hsp70 may represent a new therapeutic approach against Aβ42 and other extracellular amyloids. The potential applications of this engineered chaperone are discussed.

  9. Hsp47 and cyclophilin B traverse the endoplasmic reticulum with procollagen into pre-Golgi intermediate vesicles. A role for Hsp47 and cyclophilin B in the export of procollagen from the endoplasmic reticulum.

    Science.gov (United States)

    Smith, T; Ferreira, L R; Hebert, C; Norris, K; Sauk, J J

    1995-08-04

    Hsp47 and cyclophilin B (CyPB) are residents of the endoplasmic reticulum (ER). Both of these proteins are closely associated with polysome-associated alpha 1(I) procollagen chains. Hsp47 possesses chaperone properties early during the translation of procollagen while the cis/trans-isomerase properties of CyPB facilitate procollagen folding. In this report, we further investigate the interaction of these proteins with procollagen I during export from the ER. To inhibit vesicular budding and retain procollagen within the ER, cells were treated with the heterotrimeric G protein inhibitor mastoparan or calphostin C, a specific inhibitor of diacylglycerol/phorbol ester binding proteins. To arrest procollagen in pre-Golgi intermediate vesicles, cells were treated with guanosine 5'-3-O-(thio)triphosphate. Pulse-chase experiments of cells labeled with [35S]methionine followed by immunoprecipitation during the chase period with anti-procollagen, anti-Hsp47, and anti-CyPB antibodies were performed to reveal the relationship between Hsp47/CyPB/procollagen I. The distribution of procollagen, Hsp47, and CyPB to the ER and/or pre-Golgi vesicles was verified by immunofluorescence. Hsp47 and CyPB remained associated with procollagen retained within the ER. Hsp47 and CyPB were also associated with procollagen exported from the ER into pre-Golgi intermediate vesicles. Treatment of cells with cyclosporin A diminished the levels of CyPB bound to procollagen and diminished the rate of Hsp47 released from procollagen and the rate of procollagen secretion, suggesting that Hsp47 release from procollagen may be driven by helix formation. Also, these studies suggest that Hsp47 may resemble protein disulfide isomerase and possess both chaperone and anti-chaperone properties. During translation, high levels of Hsp47 are seen to limit protein aggregation and facilitate chain registration. Later, Hsp47 and/or CyPB and protein disulfide isomerase act as anti-chaperones and provide the basis for

  10. HDAC6 inhibition enhances 17-AAG--mediated abrogation of hsp90 chaperone function in human leukemia cells.

    Science.gov (United States)

    Rao, Rekha; Fiskus, Warren; Yang, Yonghua; Lee, Pearl; Joshi, Rajeshree; Fernandez, Pravina; Mandawat, Aditya; Atadja, Peter; Bradner, James E; Bhalla, Kapil

    2008-09-01

    Histone deacetylase 6 (HDAC6) is a heat shock protein 90 (hsp90) deacetylase. Treatment with pan-HDAC inhibitors or depletion of HDAC6 by siRNA induces hyperacetylation and inhibits ATP binding and chaperone function of hsp90. Treatment with 17-allylamino-demothoxy geldanamycin (17-AAG) also inhibits ATP binding and chaperone function of hsp90, resulting in polyubiquitylation and proteasomal degradation of hsp90 client proteins. In this study, we determined the effect of hsp90 hyperacetylation on the anti-hsp90 and antileukemia activity of 17-AAG. Hyperacetylation of hsp90 increased its binding to 17-AAG, as well as enhanced 17-AAG-mediated attenuation of ATP and the cochaperone p23 binding to hsp90. Notably, treatment with 17-AAG alone also reduced HDAC6 binding to hsp90 and induced hyperacetylation of hsp90. This promoted the proteasomal degradation of HDAC6. Cotreatment with 17-AAG and siRNA to HDAC6 induced more inhibition of hsp90 chaperone function and depletion of BCR-ABL and c-Raf than treatment with either agent alone. In addition, cotreatment with 17-AAG and tubacin augmented the loss of survival of K562 cells and viability of primary acute myeloid leukemia (AML) and chronic myeloid leukemia (CML) samples. These findings demonstrate that HDAC6 is an hsp90 client protein and hyperacetylation of hsp90 augments the anti-hsp90 and antileukemia effects of 17-AAG.

  11. Investigating the Chaperone Properties of a Novel Heat Shock Protein, Hsp70.c, from Trypanosoma brucei

    Directory of Open Access Journals (Sweden)

    Adélle Burger

    2014-01-01

    Full Text Available The neglected tropical disease, African Trypanosomiasis, is fatal and has a crippling impact on economic development. Heat shock protein 70 (Hsp70 is an important molecular chaperone that is expressed in response to stress and Hsp40 acts as its co-chaperone. These proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. A novel cytosolic Hsp70, from Trypanosoma brucei, TbHsp70.c, contains an acidic substrate binding domain and lacks the C-terminal EEVD motif. The ability of a cytosolic Hsp40 from Trypanosoma brucei J protein 2, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated. The main objective was to functionally characterize TbHsp70.c to further expand our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed the ability to suppress aggregation of thermolabile MDH and chemically denatured rhodanese. ATPase assays revealed a 2.8-fold stimulation of the ATPase activity of TbHsp70.c by Tbj2. TbHsp70.c and Tbj2 both demonstrated chaperone activity and Tbj2 functions as a co-chaperone of TbHsp70.c. In vivo heat stress experiments indicated upregulation of the expression levels of TbHsp70.c.

  12. Radiation therapy induces circulating serum Hsp72 in patients with prostate cancer

    International Nuclear Information System (INIS)

    Hurwitz, Mark D.; Kaur, Punit; Nagaraja, Ganachari M.; Bausero, Maria A.; Manola, Judith; Asea, Alexzander

    2010-01-01

    Background and purpose: Hsp72 found in the extracellular milieu has been shown to play an important role in immune regulation. The impact of common cancer therapies on extracellular release of Hsp72 however, has been to date undefined. Materials and methods: Serum from 13 patients undergoing radiation therapy (XRT) for prostate cancer with or without hormonal therapy (ADT) was measured for levels of circulating serum Hsp72 and pro-inflammatory cytokines (IL-6 and TNF-α) using the classical sandwich ELISA technique and the relative expression of CD8 + T lymphocytes and natural killer (NK) cells was measured using flow cytometry. Mouse orthotopic xenograft of human prostate cancer tumors (DU-145 and PC-3) were used to validate and further characterize the response noted in the clinical setting. The biological significance of tumor released Hsp72 was studied in human dendritic cells (DC) in vitro. Results: Circulating serum Hsp72 levels increased an average of 3.5-fold (median per patient 4.8-fold) with XRT but not with ADT (p = 0.0002). Increases in IL-6 (3.3-fold), TNF-α (1.8-fold), CD8 + CTL (2.1-fold) and NK cells (3.2-fold) also occurred. Using PC-3 and DU-145 human prostate cancer xenograft models in mice, we confirmed that XRT induces Hsp72 release primarily from implanted tumors. In vitro studies using supernatant recovered from irradiated human prostate cancer cells point to exosomes containing Hsp72 as a possible stimulator of pro-inflammatory cytokine production and costimulatory molecules expression in human DC. Conclusions: The current study confirms for the first time in an actual clinical setting elevation of circulating serum Hsp72 with XRT. The accompanying studies in mice and in vitro identify the released exosomes containing Hsp72 as playing a pivotal role in stimulating pro-inflammatory immune responses. These findings, if validated, may lead to new treatment paradigms for common human malignancies.

  13. Characterization of HSP27 phosphorylation sites in human atherosclerotic plaque secretome

    DEFF Research Database (Denmark)

    Durán, Mari-Carmen; Boeri-Erba, Elisabetta; Mohammed, Shabaz

    2007-01-01

    spectrometry (MS). Among the identified proteins, two isoforms of heat shock protein 27 (HSP27), a protein recently described as a potential biomarker of atherosclerosis, were detected. However, the putative mechanisms in which HSP27 isoforms could be involved in the atherosclerotic process are unknown. Thus......, the role that phosphorylated HSP27 could play in the atherosclerotic process is actually under study. The present work shows the strategies employed to characterize the phosphorylation in the HSP27 secreted by atheroma plaque samples. The application of liquid chromatography tandem mass spectrometry (MS......-lymphocytes). These interactions can be mediated by proteins secreted from these cells, which therefore exert an important role in the atherosclerotic process. We recently described a novel strategy for the characterization of the human atherosclerotic plaque secretome, combining two-dimensional gel electrophoresis and mass...

  14. A new lease of life for the Farmer-Baldwin dosemeter

    International Nuclear Information System (INIS)

    Vojnovic, B.

    1984-01-01

    Replacement batteries for the widely used 'Farmer-Baldwin Sub-standard x-ray Dosemeter' (Farmer 1955), manufactured by Baldwin Industrial Controls, of Dartford, Kent, have become expensive and difficult to obtain, resulting in a number of such units being unnecessarily taken out of service. This note describes how the relatively simple addition of a DC-DC inverter can drastically reduce the maintenance costs of the instrument (MK2 version) by powering it from three commonly available 1.5 V cells, type U2 (IEC type R20). The function of the various controls on the instrument is not affected in any way. (author)

  15. Protective Effect of HSP25 on Radiation Induced Tissue Damage

    International Nuclear Information System (INIS)

    Lee, Hae-June; Lee, Yoon-Jin; Kwon, Hee-Choong; Bae, Sang-Woo; Lee, Yun-Sil; Kim, Sung Ho

    2007-01-01

    Control of cancer by irradiation therapy alone or in conjunction with combination chemotherapy is often limited by organ specific toxicity. Ionizing irradiation toxicity is initiated by damage to normal tissue near the tumor target and within the transit volume of radiotherapy beams. Irradiation-induced cellular, tissue, and organ damage is mediated by acute effects, which can be dose limiting. A latent period follows recovery from the acute reaction, then chronic irradiation fibrosis (late effects) pose a second cause of organ failure. HSP25/27 has been suggested to protect cells against apoptotic cell death triggered by hyperthermia, ionizing radiation, oxidative stress, Fas ligand, and cytotoxic drugs. And several mechanisms have been proposed to account for HSP27-mediated apoptotic protection. However radioprotective effect of HSP25/27 in vivo system has not yet been evaluated. The aim of this study was to evaluate the potential of exogenous HSP25 expression, as delivered by adenoviral vectors, to protect animal from radiation induced tissue damage

  16. Expression analysis of HSP70 in the testis of Octopus tankahkeei under thermal stress.

    Science.gov (United States)

    Long, Ling-Li; Han, Ying-Li; Sheng, Zhang; Du, Chen; Wang, You-Fa; Zhu, Jun-Quan

    2015-09-01

    The gene encoding heat shock protein 70 (HSP70) was identified in Octopus tankahkeei by homologous cloning and rapid amplification of cDNA ends (RACE). The full-length cDNA (2471 bp) consists of a 5'-untranslated region (UTR) (89 bp), a 3'-UTR (426 bp), and an open reading frame (1956 bp) that encodes 651 amino acid residues with a predicted molecular mass of 71.8 kDa and an isoelectric point of 5.34. Based on the amino acid sequence analysis and multiple sequence alignment, this cDNA is a member of cytoplasmic hsp70 subfamily of the hsp70 family and was designated as ot-hsp70. Tissue expression analysis showed that HSP70 expression is highest in the testes when all examined organs were compared. Immunohistochemistry analysis, together with hematoxylin-eosin staining, revealed that the HSP70 protein was expressed in all spermatogenic cells, but not in fibroblasts. In addition, O. tankahkeei were heat challenged by exposure to 32 °C seawater for 2 h, then returned to 13 °C for various recovery time (0-24 h). Relative expression of ot-hsp70 mRNA in the testes was measured at different time points post-challenge by quantitative real-time PCR. A clear time-dependent mRNA expression of ot-hsp70 after thermal stress indicates that the HSP70 gene is inducible. Ultrastructural changes of the heat-stressed testis were observed by transmission electron microscopy. We suggest that HSP70 plays an important role in spermatogenesis and testis protection against thermal stress in O. tankahkeei. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Expression of three sHSP genes involved in heat pretreatment-induced chilling tolerance in banana fruit.

    Science.gov (United States)

    He, Li-hong; Chen, Jian-ye; Kuang, Jian-fei; Lu, Wang-jin

    2012-07-01

    Banana fruit is highly susceptible to chilling injury. In previous research it was shown that heat pretreatment of banana fruit at 38 °C for 3 days before storage at a chilling temperature of 8 °C for 12 days prevented increases in visible chilling injury index, electrolyte leakage and malondialdehyde content and also decreases in lightness and chroma, indicating that heat pretreatment could effectively alleviate chilling injury of banana fruit. However, little is known about the role of small heat shock proteins (sHSPs) in postharvest chilling tolerance of banana fruit. In the present study, three cytosolic sHSP expression profiles in peel and pulp tissues of banana fruit during heat pretreatment and subsequent chilled storage (8 °C) were investigated in relation to heat pretreatment-induced chilling tolerance. Three full-length cDNAs of cytosolic sHSP genes, including two class I sHSP (CI sHSP) and one class II sHSP (CII sHSP) cDNAs, named Ma-CI sHSP1, Ma-CI sHSP2 and Ma-CII sHSP3 respectively, were isolated and characterised from harvested banana fruit. Accumulation of Ma-CI sHSP1 mRNA transcripts in peel and pulp tissues and Ma-CII sHSP3 mRNA transcripts in peel tissue increased during heat pretreatment. Expression of all three Ma-sHSP genes in peel and pulp tissues was induced during subsequent chilled storage. Furthermore, Ma-CI sHSP1 and Ma-CII sHSP3 mRNA transcripts in pulp tissue and Ma-CI sHSP2 mRNA transcripts in peel and pulp tissues were obviously enhanced by heat pretreatment at days 6 and 9 of subsequent chilled storage. These results suggested that heat pretreatment enhanced the expression of Ma-sHSPs, which might be involved in heat pretreatment-induced chilling tolerance of banana fruit. Copyright © 2012 Society of Chemical Industry.

  18. Requirement of Hsp105 in CoCl{sub 2}-induced HIF-1α accumulation and transcriptional activation

    Energy Technology Data Exchange (ETDEWEB)

    Mikami, Hiroki; Saito, Youhei, E-mail: ysaito@mb.kyoto-phu.ac.jp; Okamoto, Namiko; Kakihana, Ayana; Kuga, Takahisa; Nakayama, Yuji, E-mail: nakayama@mb.kyoto-phu.ac.jp

    2017-03-15

    The mammalian stress protein Hsp105α protects cells from stress conditions. Several studies have indicated that Hsp105α is overexpressed in many types of solid tumors, which contain hypoxic microenvironments. However, the role of Hsp105α in hypoxic tumors remains largely unknown. We herein demonstrated the involvement of Hsp105α in HIF-1 functions induced by the hypoxia-mimetic agent CoCl{sub 2}. While Hsp105α is mainly localized in the cytoplasm under normal conditions, a treatment with CoCl{sub 2} induces the nuclear localization of Hsp105α, which correlated with HIF-1α expression levels. The overexpression of degradation-resistant HIF-1α enhances the nuclear localization of Hsp105α without the CoCl{sub 2} treatment. The CoCl{sub 2}-dependent transcriptional activation of HIF-1, which is measured using a reporter gene containing a HIF-responsive element, is reduced by the knockdown of Hsp105α. Furthermore, the CoCl{sub 2}-induced accumulation of HIF-1α is enhanced by heat shock, which results in the nuclear localization of Hsp105, and is suppressed by the knockdown of Hsp105. Hsp105 associates with HIF-1α in CoCl{sub 2}-treated cells. These results suggest that Hsp105α plays an important role in the functions of HIF-1 under hypoxic conditions, in which Hsp105α enhances the accumulation and transcriptional activity of HIF-1 through the HIF-1α-mediated nuclear localization of Hsp105α. - Highlights: • Hsp105α is required for the CoCl{sub 2}-induced transcriptional activation and accumulation of HIF-1. • Hsp105α localizes to the nucleus and interacts with HIF-1α in CoCl{sub 2}-treated cells. • Hsp105 enhances the CoCl{sub 2}-induced accumulation of HIF-1α under heat shock conditions.

  19. HSP27 phosphorylation modulates TRAIL-induced activation of Src-Akt/ERK signaling through interaction with β-arrestin2.

    Science.gov (United States)

    Qi, Shimei; Xin, Yinqiang; Qi, Zhilin; Xu, Yimiao; Diao, Ying; Lan, Lei; Luo, Lan; Yin, Zhimin

    2014-03-01

    Heat shock protein 27 (HSP27) regulates critical cellular functions such as development, differentiation, cell growth and apoptosis. A variety of stimuli induce the phosphorylation of HSP27, which affects its cellular functions. However, most previous studies focused on the role of HSP27 protein itself in apoptosis, the particular role of its phosphorylation state in signaling transduction remains largely unclear. In the present study, we reported that HSP27 phosphorylation modulated TRAIL-triggered pro-survival signaling transduction. In HeLa cells, suppression of HSP27 phosphorylation by specific inhibitor KRIBB3 or MAPKAPK2 (MK2) knockdown and by overexpression of non-phosphorylatable HSP27(3A) mutant demonstrated that hindered HSP27 phosphorylation enhanced the TRAIL-induced apoptosis. In addition, reduced HSP27 phosphorylation by KRIBB3 treatment or MK2 knockdown attenuated the TRAIL-induced activation of Akt and ERK survival signaling through suppressing the phosphorylation of Src. By overexpression of HSP27(15A) or HSP27(78/82A) phosphorylation mutant, we further showed that phosphorylation of HSP27 at serine 78/82 residues was essential to TRAIL-triggered Src-Akt/ERK signaling transduction. Co-immunoprecipitation and confocal microscopy showed that HSP27 interacted with Src and scaffolding protein β-arrestin2 in response of TRAIL stimulation and suppression of HSP27 phosphorylation apparently disrupted the TRAIL-induced interaction of HSP27 and Src or interaction of HSP27 and β-arrestin2. We further demonstrated that β-arrestin2 mediated HSP27 action on TRAIL-induced Src activation, which was achieved by recruiting signaling complex of HSP27/β-arrestin2/Src in response to TRAIL. Taken together, our study revealed that HSP27 phosphorylation modulates TRAIL-triggered activation of Src-Akt/ERK pro-survival signaling via interacting with β-arrestin2 in HeLa cells. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Heat shock proteins (Hsp 70) response is not systematic to cell stress

    International Nuclear Information System (INIS)

    Hassen, Wafa; Ayed-Boussema, Imen; Bouslimi, Amel; Bacha, Hassen

    2007-01-01

    Ochratoxin A (OTA) is a mycotoxin routinely detected in improperly stored animal and human food supplies as well as in human sera worldwide. OTA has multiple toxic effects; however, the most prominent is nephrotoxicity. Thus, OTA is involved in the pathogenesis of human nephropathy in Balkan areas. In this study, we address the question of the appropriate functioning of the basal cellular defense mechanisms, after exposure to OTA, which, up to now, has not been investigated satisfactorily. In this context, we have monitored the effect of OTA on (i) the inhibition of cell viability, (ii) the oxidative damage using the GSH depletion, (iii) the inhibition of protein synthesis through the incorporation of [ 3 H] Leucine and (iv) the induction of Hsp 70 gene expression as a parameter of cytotoxicity, oxidative damage and particularly as a protective and adaptative response. This study was conducted using the Human Hep G2 hepatocytes and monkey kidney Vero cells under exposure conditions ranging from non-cytotoxic to sub-lethal. Our results clearly showed that OTA inhibits cell proliferation, strongly reduces protein synthesis and induces the decrease of GSH in concentration-dependent manner in both Hep G2 and Vero cells. However, although cytotoxicity and oxidative damage (main inducers of Hsp expression) occur, no change was observed in Hsp 70 level under the multiple tested conditions. Inhibition of protein synthesis could not explain the absence of Hsp 70 response since concentrations, which did not influence protein synthesis, also failed to display the expected Hsp 70 response. Our data are consistent with recently published reports where considerable differences were noticed in the ability of relevant toxicants to induce Hsp. These results raised doubt about the universal character of Hsp induction which seems to be more complex than originally envisioned. It could be concluded that Hsp 70 induction is not systematic to cell stress

  1. MCNP SIMULATION OF THE HP(10) ENERGY RESPONSE OF A BRAZILIAN TLD ALBEDO NEUTRON INDIVIDUAL DOSEMETER, FROM THERMAL TO 20 MeV.

    Science.gov (United States)

    Freitas, B M; Martins, M M; Pereira, W W; da Silva, A X; Mauricio, C L P

    2016-09-01

    The Brazilian Instituto de Radioproteção e Dosimetria (IRD) runs a neutron individual monitoring system with a home-made TLD albedo dosemeter. It has already been characterised and calibrated in some reference fields. However, the complete energy response of this dosemeter is not known, and the calibration factors for all monitored workplace neutron fields are difficult to be obtained experimentally. Therefore, to overcome such difficulties, Monte Carlo simulations have been used. This paper describes the simulation of the HP(10) neutron response of the IRD TLD albedo dosemeter using the MCNPX transport code, for energies from thermal to 20 MeV. The validation of the MCNPX modelling is done comparing the simulated results with the experimental measurements for ISO standard neutron fields of (241)Am-Be, (252)Cf, (241)Am-B and (252)Cf(D2O) and also for (241)Am-Be source moderated with paraffin and silicone. Bare (252)Cf are used for normalisation. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Molecular mechanism of allosteric communication in Hsp70 revealed by molecular dynamics simulations.

    Directory of Open Access Journals (Sweden)

    Federica Chiappori

    Full Text Available Investigating ligand-regulated allosteric coupling between protein domains is fundamental to understand cell-life regulation. The Hsp70 family of chaperones represents an example of proteins in which ATP binding and hydrolysis at the Nucleotide Binding Domain (NBD modulate substrate recognition at the Substrate Binding Domain (SBD. Herein, a comparative analysis of an allosteric (Hsp70-DnaK and a non-allosteric structural homolog (Hsp110-Sse1 of the Hsp70 family is carried out through molecular dynamics simulations, starting from different conformations and ligand-states. Analysis of ligand-dependent modulation of internal fluctuations and local deformation patterns highlights the structural and dynamical changes occurring at residue level upon ATP-ADP exchange, which are connected to the conformational transition between closed and open structures. By identifying the dynamically responsive protein regions and specific cross-domain hydrogen-bonding patterns that differentiate Hsp70 from Hsp110 as a function of the nucleotide, we propose a molecular mechanism for the allosteric signal propagation of the ATP-encoded conformational signal.

  3. Repurposing Hsp104 to Antagonize Seminal Amyloid and Counter HIV Infection.

    Science.gov (United States)

    Castellano, Laura M; Bart, Stephen M; Holmes, Veronica M; Weissman, Drew; Shorter, James

    2015-08-20

    Naturally occurring proteolytic fragments of prostatic acid phosphatase (PAP248-286 and PAP85-120) and semenogelins (SEM1 and SEM2) form amyloid fibrils in seminal fluid, which capture HIV virions and promote infection. For example, PAP248-286 fibrils, termed SEVI (semen-derived enhancer of viral infection), can potentiate HIV infection by several orders of magnitude. Here, we design three disruptive technologies to rapidly antagonize seminal amyloid by repurposing Hsp104, an amyloid-remodeling nanomachine from yeast. First, Hsp104 and an enhanced engineered variant, Hsp104(A503V), directly remodel SEVI and PAP85-120 fibrils into non-amyloid forms. Second, we elucidate catalytically inactive Hsp104 scaffolds that do not remodel amyloid structure, but cluster SEVI, PAP85-120, and SEM1(45-107) fibrils into larger assemblies. Third, we modify Hsp104 to interact with the chambered protease ClpP, which enables coupled remodeling and degradation to irreversibly clear SEVI and PAP85-120 fibrils. Each strategy diminished the ability of seminal amyloid to promote HIV infection, and could have therapeutic utility. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. The use of TLD-700H dosemeters in the assessment of external doses at the former Semipalatinsk nuclear test site.

    Science.gov (United States)

    Hill, P; Dederichs, H; Pillath, J; Schlecht, W; Hille, R; Artemev, O; Ptitskaya, L; Akhmetov, M

    2002-01-01

    The joint projects performed since 1995 by the Jülich Research Centre in co-operation with the Kazakh National Nuclear Centre in the area of the former nuclear test site near Semipalatinsk, in eastern Kazakhstan, have assessed the current dose rate of the population at and around the test site, as well as determining retrospectively the dose rate of persons affected by the atmospheric tests. Measurements of the population by personal dosemeters depend on reliably wearing these dosemeters over prolonged periods of time, and of a sufficient dosemeter return. In the past, such measurements have been particularly successful whenever short wearing times were possible. This requires high sensitivity of the dosemeters. The suitability of the highly sensitive TLD material of the BICRON TLD 700H type for such personal dosimetry measurements was investigated. It was tested in practical field application at the Semipalatinsk nuclear test site in September 2000. Initial results are available from individual doses received by a group of geologists and a group of herdsmen at the test site. For the first time, the individual dose was measured directly in these population groups. Detection limits below 1 microSv permit informative measurements for wearing times of less than two weeks. Most individual doses did not arise significantly out of local fluctuations of natural background. A conservative assessment from the aspect of practical health physics yielded a mean personal dose of 0.55 microSv per day for the herdsmen, whereas the geologists received a mean personal dose of 0.45 microSv per day. For an annual exposure period of typically, about three months, the radiation dose received by the persons investigated, in addition to the natural radiation exposure, is thus well below the international limit value of 1 mSv x a(-1) for the population dose.

  5. Hsp60-induced tolerance in the rotifer Brachionus plicatilis exposed to multiple environmental contaminants.

    Science.gov (United States)

    Wheelock, C E; Wolfe, M F; Olsen, H; Tjeerdema, R S; Sowby, M L

    1999-04-01

    Hsp60 induction was selected as a sublethal endpoint of toxicity for Brachionus plicatilis exposed to a water accommodated fraction (WAF) of Prudhoe Bay crude oil (PBCO), a PBCO/dispersant (Corexit 9527(R)) fraction and Corexit 9527(R) alone. To examine the effect of multiple stressors, exposures modeled San Francisco Bay, where copper levels are approximately 5 microgram/L, salinity is 22 per thousand, significant oil transport and refining occurs, and petroleum releases have occurred historically. Rotifers were exposed to copper at 5 microgram/L for 24 h, followed by one of the oil/dispersant preparations for 24 h. Batch-cultured rotifers were used in this study to model wild populations instead of cysts. SDS-PAGE with Western Blotting using hsp60-specific antibodies and chemiluminescent detection were used to isolate, identify, and measure induced hsp60 as a percentage of control values. Both PBCO/dispersant and dispersant alone preparations induced significant levels of hsp60. However, hsp60 expression was reduced to that of controls at high WAF concentrations, suggesting interference with protein synthesis. Rotifers that had been preexposed to copper maintained elevated levels of hsp60 upon treatment with WAF at all concentrations. Results suggest that induction of hsp60 by chronic low-level exposure may serve as a protective mechanism against subsequent or multiple stressors and that hsp60 levels are not additive for the toxicants tested in this study, giving no dose-response relationship. The methods employed in this study could be useful for quantifying hsp60 levels in wild rotifer populations.

  6. Cr-39 fast neutron dosemeter based on A (n, α) converter

    International Nuclear Information System (INIS)

    Widayati, S.; Budiantari, T.

    1998-01-01

    The aim of this experiment is to obtained the response of Cr-39 as fast neutron dosemeter based on an (n, α) converter. Cr-39 was irradiated to AmBe fast neutron flux from 0.10 mSv to 2.5 mSv. Cr-39 processed by chemical etching with NaOH 20 % at temperature of 60 oC in six hours. The results of experiment showed that the response of Cr-39 based on an (n, α) converter is 6 times bigger than the response of Cr-39 without (n, α) converter. (author)

  7. Plasmodium falciparum Hep1 Is Required to Prevent the Self Aggregation of PfHsp70-3.

    Directory of Open Access Journals (Sweden)

    David O Nyakundi

    Full Text Available The majority of mitochondrial proteins are encoded in the nucleus and need to be imported from the cytosol into the mitochondria, and molecular chaperones play a key role in the efficient translocation and proper folding of these proteins in the matrix. One such molecular chaperone is the eukaryotic mitochondrial heat shock protein 70 (Hsp70; however, it is prone to self-aggregation and requires the presence of an essential zinc-finger protein, Hsp70-escort protein 1 (Hep1, to maintain its structure and function. PfHsp70-3, the only Hsp70 predicted to localize in the mitochondria of P. falciparum, may also rely on a Hep1 orthologue to prevent self-aggregation. In this study, we identified a putative Hep1 orthologue in P. falciparum and co-expression of PfHsp70-3 and PfHep1 enhanced the solubility of PfHsp70-3. PfHep1 suppressed the thermally induced aggregation of PfHsp70-3 but not the aggregation of malate dehydrogenase or citrate synthase, thus showing specificity for PfHsp70-3. Zinc ions were indeed essential for maintaining the function of PfHep1, as EDTA chelation abrogated its abilities to suppress the aggregation of PfHsp70-3. Soluble and functional PfHsp70-3, acquired by co-expression with PfHep-1, will facilitate the biochemical characterisation of this particular Hsp70 protein and its evaluation as a drug target for the treatment of malaria.

  8. Hsp90α regulates ATM and NBN functions in sensing and repair of DNA double-strand breaks.

    Science.gov (United States)

    Pennisi, Rosa; Antoccia, Antonio; Leone, Stefano; Ascenzi, Paolo; di Masi, Alessandra

    2017-08-01

    The molecular chaperone heat shock protein 90 (Hsp90α) regulates cell proteostasis and mitigates the harmful effects of endogenous and exogenous stressors on the proteome. Indeed, the inhibition of Hsp90α ATPase activity affects the cellular response to ionizing radiation (IR). Although the interplay between Hsp90α and several DNA damage response (DDR) proteins has been reported, its role in the DDR is still unclear. Here, we show that ataxia-telangiectasia-mutated kinase (ATM) and nibrin (NBN), but not 53BP1, RAD50, and MRE11, are Hsp90α clients as the Hsp90α inhibitor 17-(allylamino)-17-demethoxygeldanamycin (17-AAG) induces ATM and NBN polyubiquitination and proteosomal degradation in normal fibroblasts and lymphoblastoid cell lines. Hsp90α-ATM and Hsp90α-NBN complexes are present in unstressed and irradiated cells, allowing the maintenance of ATM and NBN stability that is required for the MRE11/RAD50/NBN complex-dependent ATM activation and the ATM-dependent phosphorylation of both NBN and Hsp90α in response to IR-induced DNA double-strand breaks (DSBs). Hsp90α forms a complex also with ph-Ser1981-ATM following IR. Upon phosphorylation, NBN dissociates from Hsp90α and translocates at the DSBs, while phThr5/7-Hsp90α is not recruited at the damaged sites. The inhibition of Hsp90α affects nuclear localization of MRE11 and RAD50, impairs DDR signaling (e.g., BRCA1 and CHK2 phosphorylation), and slows down DSBs repair. Hsp90α inhibition does not affect DNA-dependent protein kinase (DNA-PK) activity, which possibly phosphorylates Hsp90α and H2AX after IR. Notably, Hsp90α inhibition causes H2AX phosphorylation in proliferating cells, this possibly indicating replication stress events. Overall, present data shed light on the regulatory role of Hsp90α on the DDR, controlling ATM and NBN stability and influencing the DSBs signaling and repair. © 2017 Federation of European Biochemical Societies.

  9. Development of a microarray-based assay for efficient testing of new HSP70/DnaK inhibitors.

    Science.gov (United States)

    Mohammadi-Ostad-Kalayeh, Sona; Hrupins, Vjaceslavs; Helmsen, Sabine; Ahlbrecht, Christin; Stahl, Frank; Scheper, Thomas; Preller, Matthias; Surup, Frank; Stadler, Marc; Kirschning, Andreas; Zeilinger, Carsten

    2017-12-15

    A facile method for testing ATP binding in a highly miniaturized microarray environment using human HSP70 and DnaK from Mycobacterium tuberculosis as biological targets is reported. Supported by molecular modelling studies we demonstrate that the position of the fluorescence label on ATP has a strong influence on the binding to human HSP70. Importantly, the label has to be positioned on the adenine ring and not to the terminal phosphate group. Unlabelled ATP displaced bound Cy5-ATP from HSP70 in the micromolar range. The affinity of a well-known HSP70 inhibitor VER155008 for the ATP binding site in HSP70 was determined, with a EC 50 in the micromolar range, whereas reblastin, a HSP90-inhibitor, did not compete for ATP in the presence of HSP70. The applicability of the method was demonstrated by screening a small compound library of natural products. This unraveled that terphenyls rickenyl A and D, recently isolated from cultures of the fungus Hypoxylon rickii, are inhibitors of HSP70. They compete with ATP for the chaperone in the range of 29 µM (Rickenyl D) and 49 µM (Rickenyl A). Furthermore, the microarray-based test system enabled protein-protein interaction analysis using full-length HSP70 and HSP90 proteins. The labelled full-length human HSP90 binds with a half-maximal affinity of 5.5 µg/ml (∼40 µM) to HSP70. The data also demonstrate that the microarray test has potency for many applications from inhibitor screening to target-oriented interaction studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Heat shock protein 10 (Hsp10) in immune-related diseases: one coin, two sides

    Science.gov (United States)

    Jia, Haibo; Halilou, Amadou I.; Hu, Liang; Cai, Wenqian; Liu, Jing; Huang, Bo

    2011-01-01

    Heat shock protein 10 (Hsp10) in eukaryotes, originally identified as a mitochondrial chaperone, now is also known to be present in cytosol, cell surface, extracellular space and peripheral blood. Functionally besides participating in mitochondrial protein folding in association with Hsp60, Hsp10 appears to be related to pregnancy, cancer and autoimmune inhibition. Hsp10 can be released to peripheral blood at very early time point of pregnancy and given another name called early pregnancy factor (EPF), which seems to play a critical role in developing a pregnant niche. In malignant disorders, Hsp10 is usually abnormally expressed in the cytosol of malignant cells and further released to extracellular space, resulting in tumor-promoting effect from various aspects. Furthermore, distinct from other heat shock protein members, whose soluble form is recognized as danger signal by immune cells and triggers immune responses, Hsp10 after release, however, is designed to be an inhibitory signal by limiting immune response. This review discusses how Hsp10 participates in various physiological and pathological processes from basic protein molecule folding to pregnancy, cancer and autoimmune diseases, and emphasizes how important the location is for the function exertion of a molecule. PMID:21969171

  11. Induction of hsp70 by the herbicide oxyfluorfen (Goal) in the Egyptian Nile fish, Oreochromis niloticus.

    Science.gov (United States)

    Hassanein, H M; Banhawy, M A; Soliman, F M; Abdel-Rehim, S A; Müller, W E; Schröder, H C

    1999-07-01

    This paper deals with the expression of the biomarker hsp70 in the liver and kidney of the freshwater fish Oreochromis niloticus following exposure to the herbicide oxyfluorfen (Goal). Fishes were exposed to three concentrations, the 96-h LC50 (3 mg/L), the 96-h (1/2)LC50 (1.5 mg/L), and the 96-h (1/4)LC50 (0.75 mg/L) of oxyfluorfen for 6, 15, and 24 days, respectively, and samples were taken at three different time periods for each concentration. The livers responded to the herbicide by an induction of the expression of both the constitutive (hsp75; Mr 75 kDa) and the inducible (hsp73; Mr 73 kDa) hsp70 proteins. In kidney, the herbicide induced a time-dependent increase in the expression of the constitutive hsp70 (hsp75) as well, but the inducible hsp70 (hsp73) required much longer incubation periods to reach maximal levels (15 and 24 days). Our results suggest that expression of hsp70 in fish is a sensitive indicator of cellular responses to herbicide exposure in the aquatic environment.

  12. Neutron dosimetry inside the containment building of Spanish nuclear power plants with PADC based dosemeters

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Fuste, M.J. [Grup de Fisica de les Radiacions. Departament de Fisica. Edifici C. Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Domingo, C., E-mail: carles.domingo@uab.ca [Grup de Fisica de les Radiacions. Departament de Fisica. Edifici C. Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Amgarou, K.; Bouassoule, T.; Castelo, J. [Grup de Fisica de les Radiacions. Departament de Fisica. Edifici C. Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain)

    2009-10-15

    The Spanish Nuclear Safety Council (Consejo de Seguridad Nuclear, CSN) recommends performing neutron individual dose assignments at workplaces based on ambient dose equivalent measurements using area monitors and by estimating the amount of time that workers spend in the different monitored environments. In addition, some Spanish nuclear power plants estimate the neutron dose equivalent using albedo thermoluminescence dosemeters (TLD). In the period 2004-2006, our group, together with other research centers, participated in a project, funded by the CSN, with the support of the Spanish Nuclear Power Plants Association (UNESA), to investigate in situ which could be the best practical procedure for individual neutron dose monitoring in nuclear power plants. As part of this survey, several units of the UAB PADC based neutron dosemeter were exposed, on a methacrylate phantom simulating a human body, at four different places inside the containment building of the Asco I nuclear power plant. The influence of different types of calibration neutron fields is analysed and the dose equivalent for each point is estimated.

  13. HSP60 may predict good pathological response to neoadjuvant chemoradiotherapy in bladder cancer

    International Nuclear Information System (INIS)

    Urushibara, Masayasu; Kageyama, Yukio; Akashi, Takumi; Otsuka, Yukihiro; Takizawa, Touichiro; Koike, Morio; Kihara, Kazunori

    2007-01-01

    Heat shock proteins (HSPs) play crucial roles in cellular responses to stressful conditions. Expression of HSPs in invasive or high-risk superficial bladder cancer was investigated to identify whether HSPs predict pathological response to neoadjuvant chemoradiotherapy (CRT). Immunohistochemistry was used to assess expression levels of HSP27, HSP60, HSP70, HSP90 and p53 in 54 patients with invasive or high-risk superficial bladder cancer, prior to low-dose neoadjuvant CRT, followed by radical or partial cystectomy. Patients were classified into two groups (good or poor responders) depending on pathological response to CRT, which was defined as the proportion of morphological therapeutic changes in surgical specimens. Good responders showed morphological therapeutic changes in two-thirds or more of tumor tissues. In contrast, poor responders showed changes in less than two-thirds of tumor tissues. Using a multivariate analysis, positive HSP60 expression prior to CRT was found to be marginally associated with good pathological response to CRT (P=0.0564). None of clinicopathological factors was associated with HSP60 expression level. In the good pathological responders, the 5-year cause-specific survival was 88%, which was significantly better than survival in the poor responders (51%) (P=0.0373). Positive HSP60 expression prior to CRT may predict good pathological response to low-dose neoadjuvant CRT in invasive or high-risk superficial bladder cancer. (author)

  14. Technical specification of the NRPB thermoluminescent dosemeter used for the measurement of body dose and skin dose

    CERN Document Server

    Shaw, K B

    1977-01-01

    This report specifies the NRPB thermoluminescent dosemeter used for the measurement of radiation dose in tissue at a depth of 700 mg cm sup - sup 2 (body dose) and at a depth of 5-10 mg cm sup - sup 2 (skin dose).

  15. Comparison of responses of thermoluminescent dosemeters irradiated by soft x-rays at very low and very high dose rate levels

    International Nuclear Information System (INIS)

    Pietrikova-Farnikova, M.; Krasa, J.; Juha, L.

    1994-01-01

    Recent great progress in construction and application of bright sources of soft X-rays gave a strong impetus for the development of methods of their dosimetric diagnostics. The soft X-ray sources are primarily represented by synchrotron radiation sources and by sources based on laser-produced plasma, including X-ray lasers. Their characteristics spread over a very wide region of photon energies, peak and average powers and densities. From our preliminary experiments it follows that thermoluminescent dosemeters can serve as a suitable tool for the determination of these characteristics. Problem lies in the fact that routine use of the thermoluminescent dosemeters for the dosimetry of soft X-rays requires their spectral calibration, which can be carried out with low peak power sources (synchrotron radiation and radionuclide sources). On the contrary, many important sources, especially these based on laser-produced plasmas, exhibit a very high peak power, i.e. dosemeters are irradiated at extremely high dose rate. In comparative experiments carried out with laser-produced plasmas and radionuclides using TLD 200 (CaF 2 :Dy) and GR 200A (LiF:Mg,Cu,P) it was satisfactorily proven that total thermoluminescent signals are independent of the dose rate. Dependence of glow curve shapes on the dose, dose rate and photon energy were equally determined

  16. Hsp27 regulates Akt activation and polymorphonuclear leukocyte apoptosis by scaffolding MK2 to Akt signal complex.

    Science.gov (United States)

    Wu, Rui; Kausar, Hina; Johnson, Paul; Montoya-Durango, Diego E; Merchant, Michael; Rane, Madhavi J

    2007-07-27

    We have shown previously that Akt exists in a signal complex with p38 MAPK, MAPK-activated protein kinase-2 (MK2), and heat shock protein 27 (Hsp27) and MK2 phosphorylates Akt on Ser-473. Additionally, dissociation of Hsp27 from Akt, prior to Akt activation, induced polymorphonuclear leukocyte (PMN) apoptosis. However, the role of Hsp27 in regulating Akt activation was not examined. This study tested the hypothesis that Hsp27 regulates Akt activation and promotes cell survival by scaffolding MK2 to the Akt signal complex. Here we show that loss of Akt/Hsp27 interaction by anti-Hsp27 antibody treatment resulted in loss of Akt/MK2 interaction, loss of Akt-Ser-473 phosphorylation, and induced PMN apoptosis. Transfection of myristoylated Akt (AktCA) in HK-11 cells induced Akt-Ser-473 phosphorylation, activation, and Hsp27-Ser-82 phosphorylation. Cotransfection of AktCA with Hsp27 short interfering RNA, but not scrambled short interfering RNA, silenced Hsp27 expression, without altering Akt expression in HK-11 cells. Silencing Hsp27 expression inhibited Akt/MK2 interaction, inhibited Akt phosphorylation and Akt activation, and induced HK-11 cell death. Deletion mutagenesis studies identified acidic linker region (amino acids 117-128) on Akt as an Hsp27 binding region. Deletion of amino acids 117-128 on Akt resulted in loss of its interaction with Hsp27 and MK2 but not with Hsp90 as demonstrated by immunoprecipitation and glutathione S-transferase pulldown studies. Co-transfection studies demonstrated that constitutively active MK2 (MK2EE) phosphorylated Aktwt (wild type) on Ser-473 but failed to phosphorylate Akt(Delta117-128) mutant in transfixed cells. These studies collectively define a novel role of Hsp27 in regulating Akt activation and cellular apoptosis by mediating interaction between Akt and its upstream activator MK2.

  17. Determination of the parameters of traps in thermoluminescent dosemeters of ZrO2: Eu + Ptfe

    International Nuclear Information System (INIS)

    Nieto H, B.; Azorin N, J.; Rivera M, T.

    2002-01-01

    In this work the manufacture of dosemeters in pellets form of ZrO 2 : Eu + Ptfe is described; which after were exposed to UV radiation (260 nm) were generated the corresponding thermoluminescent curves and in the basis to the properties of symmetry of the curves it was determined the kinetic order using the Chen and the Balarin criteria. (Author)

  18. Hsp105 family proteins suppress staurosporine-induced apoptosis by inhibiting the translocation of Bax to mitochondria in HeLa cells

    International Nuclear Information System (INIS)

    Yamagishi, Nobuyuki; Ishihara, Keiichi; Saito, Youhei; Hatayama, Takumi

    2006-01-01

    Hsp105 (Hsp105α and Hsp105β), major heat shock proteins in mammalian cells, belong to a subgroup of the HSP70 family, HSP105/110. Previously, we have shown that Hsp105α has completely different effects on stress-induced apoptosis depending on cell type. However, the molecular mechanisms by which Hsp105α regulates stress-induced apoptosis are not fully understood. Here, we established HeLa cells that overexpress either Hsp105α or Hsp105β by removing doxycycline and examined how Hsp105 modifies staurosporine (STS)-induced apoptosis in HeLa cells. Apoptotic features such as the externalization of phosphatidylserine on the plasma membrane and nuclear morphological changes were induced by the treatment with STS, and the STS-induced apoptosis was suppressed by overexpression of Hsp105α or Hsp105β. In addition, we found that overexpression of Hsp105α or Hsp105β suppressed the activation of caspase-3 and caspase-9 by preventing the release of cytochrome c from mitochondria. Furthermore, the translocation of Bax to mitochondria, which results in the release of cytochrome c from the mitochondria, was also suppressed by the overexpression of Hsp105α or Hsp105β. Thus, it is suggested that Hsp105 suppresses the stress-induced apoptosis at its initial step, the translocation of Bax to mitochondria in HeLa cells

  19. Alteration of cytochrome P450 1 regulation and HSP 70 level in brain of juvenile common carp (Cyprinus carpio) after chronic exposure to tributyltin.

    Science.gov (United States)

    Li, Zhi-Hua; Zhong, Li-Qiao; Wu, Yan-Hua; Mu, Wei-Na

    2016-02-01

    Tributyltin (TBT), a toxic contaminant in aquatic environments, has bio-accumulated in aquatic food webs throughout the world and can be found at toxic levels in some biota. However, the molecular mechanisms and effects of TBT are not fully understood. The aim of the present study was to investigate the effect of long-term exposure of TBT on cytochrome P450 (CYP450) 1 regulation and heat-shock proteins (HSPs) profiling in brain of freshwater teleost. The effects of long-term exposure to TBT on mRNA expression of cytochrome P450 (CYP450) 1 family genes and ethoxyresorufin O-deethylase (EROD) activity in the brain of common carp were evaluated, as well as HSP 70 level. Fish were exposed to sublethal concentrations of TBT (75 ng/L, 0.75 μg/L and 7.5 μg/L) for 15, 30, and 60 days. Based on the results, long-term exposure (more than 15 days) to TBT could lead to obvious physiological-biochemical responses (based on EROD activity, HSP 70 level and CYP450 1 family genes expression). The mRNA expression of CYP450 1 family genes (CYP1A, CYP1B, CYP1C1 and CYP1C2) suggested that CYP1A was to accommodate most EROD activity in fish, but other CYP450 forms also involved in this proceeding. Thus, the measured physiological responses in fish brain could provide useful information to better understand the mechanisms of TBT-induced bio-toxicity and could be used as potential biomarkers for monitoring the TBT pollution in the field.

  20. Al2 O3:Cr,Ni: a possible thermoluminescent dosemeter

    International Nuclear Information System (INIS)

    Mariani R, Francisco; Roman B, Alvaro; Saavedra S, Renato; Ibarra S, Angel

    1996-01-01

    Results from a study on the thermoluminescent (Tl) emission from Al 2 O 3 :Cr,Ni are presented. The measurements were obtained for evaluation of the Al 2 O 3 :Cr,Ni dosimetric properties. Different crystal batches were exposed to two kind of ionizing radiation (X-ray and β - ). The Tl spectrum has a main peak with high thermal and optical stability, deviating from linearity for doses lower than 3.6 Gy. Furthermore, this material shows advantages (thermal resistance, reusability, multiple heating cycles) compared to TLD-100. Measured Al 2 O 3 :Cr,Ni properties indicate that it could be used as a dosemeter. (author)

  1. HIF-1α-induced HSP70 regulates anabolic responses in articular chondrocytes under hypoxic conditions.

    Science.gov (United States)

    Tsuchida, Shinji; Arai, Yuji; Takahashi, Kenji A; Kishida, Tsunao; Terauchi, Ryu; Honjo, Kuniaki; Nakagawa, Shuji; Inoue, Hiroaki; Ikoma, Kazuya; Ueshima, Keiichiro; Matsuki, Tomohiro; Mazda, Osam; Kubo, Toshikazu

    2014-08-01

    We assessed whether heat shock protein 70 (HSP70) is involved in hypoxia inducible factor 1 alpha (HIF-1α)-dependent anabolic pathways in articular chondrocytes under hypoxic conditions. Primary rabbit chondrocytes were cultured under normoxia (20% oxygen condition) or hypoxia (1% oxygen condition). Alternatively, cells cultured under normoxia were treated with CoCl2 , which induces HIF-1α, to simulate hypoxia, or transfected with siRNAs targeting HIF-1α (si-HIF-1α) and HSP70 (si-HSP70) under hypoxia. HSP70 expression was enhanced by the increased expression of HIF-1α under hypoxia or simulated hypoxia, but not in the presence of si-HIF-1α. Hypoxia-induced overexpression of ECM genes was significantly suppressed by si-HIF-1α or si-HSP70. Cell viability positively correlated with hypoxia, but transfection with si-HIF-1α or si-HSP70 abrogated the chondroprotective effects of hypoxia. Although LDH release from sodium nitroprusside-treated cells and the proportion of TUNEL positive cells were decreased under hypoxia, transfection with si-HIF-1α or si-HSP70 almost completely blocked these effects. These findings indicated that HIF-1α-induced HSP70 overexpression increased the expression levels of ECM genes and cell viability, and protected chondrocytes from apoptosis. HIF-1α may regulate the anabolic effects of chondrocytes under hypoxic conditions by regulating HSP70 expression. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  2. Hsp70 stabilizes lysosomes and reverts Niemann-Pick disease-associated lysosomal pathology

    DEFF Research Database (Denmark)

    Kirkegaard, Thomas; Roth, Anke G; Petersen, Nikolaj H T

    2010-01-01

    Heat shock protein 70 (Hsp70) is an evolutionarily highly conserved molecular chaperone that promotes the survival of stressed cells by inhibiting lysosomal membrane permeabilization, a hallmark of stress-induced cell death. Clues to its molecular mechanism of action may lay in the recently...... reported stress- and cancer-associated translocation of a small portion of Hsp70 to the lysosomal compartment. Here we show that Hsp70 stabilizes lysosomes by binding to an endolysosomal anionic phospholipid bis(monoacylglycero)phosphate (BMP), an essential co-factor for lysosomal sphingomyelin metabolism......-is also associated with a marked decrease in lysosomal stability, and this phenotype can be effectively corrected by treatment with recombinant Hsp70. Taken together, these data open exciting possibilities for the development of new treatments for lysosomal storage disorders and cancer with compounds...

  3. Investigating hsp Gene Expression in Liver of Channa striatus under Heat Stress for Understanding the Upper Thermal Acclimation

    Directory of Open Access Journals (Sweden)

    Gopal Krishna Purohit

    2014-01-01

    Full Text Available Changes in hsp gene expression profiles in murrel Channa striatus experimentally exposed to temperature stress (36°C for 4, 15, and 30 days were investigated; fish collected from aquaculture ponds and maintained in laboratory at the pond temperature (25 ± 1°C served as control. Channa collected from a hot spring runoff (36°C was included in the study to examine the hsp profiles beyond 30 days of exposure. Gene expression analyses of a battery of hsps in liver tissues were carried out by quantitative RT-PCR and protein expressions were analyzed by immunoblotting. hsps could be grouped into three clusters based on similarity in response to heat stress: hsp70, hsp78, and hsp60, whose transcript level continued to increase with duration of exposure; hsp90 and hsp110 that increased to a much higher level and then decreased; hsp27 and hsp47 that did not significantly vary as compared to control. The results suggest that Hsp70, Hsp78, and Hsp60 are involved in thermal acclimation and long term survival at high temperature. Fish living in the hot spring runoff appears to continuously express hsps that can be approximated by long term induction of hsps in farmed fish if temperature of their environment is raised to 36°C.

  4. Characterization of six small HSP genes from Chironomus riparius (Diptera, Chironomidae): Differential expression under conditions of normal growth and heat-induced stress.

    Science.gov (United States)

    Martín-Folgar, Raquel; de la Fuente, Mercedes; Morcillo, Gloria; Martínez-Guitarte, José-Luis

    2015-10-01

    Small heat shock proteins (sHSPs) comprise the most numerous, structurally diverse, and functionally uncharacterized family of heat shock proteins. Several Hsp genes (Hsp 90, 70, 40, and 27) from the insect Chironomus riparius are widely used in aquatic toxicology as biomarkers for environmental toxins. Here, we conducted a comparative study and characterized secondary structure of the six newly identified sHsp genes Hsp17, Hsp21, Hsp22, Hsp23, Hsp24, and Hsp34. A characteristic α-crystallin domain is predicted in all the new proteins. Phylogenetic analysis suggests a strong relation to other sHSPs from insects and interesting evidence regarding evolutionary origin and duplication events. Comparative analysis of transcription profiles for Hsp27, Hsp70, and the six newly identified genes revealed that Hsp17, Hsp21, and Hsp22 are constitutively expressed under normal conditions, while under two different heat shock conditions these genes are either not activated or are even repressed (Hsp22). In contrast, Hsp23, Hsp24, and Hsp34 are significantly activated along with Hsp27 and Hsp70 during heat stress. These results strongly suggest functional differentiation within the small HSP subfamily and provide new data to help understand the coping mechanisms induced by stressful environmental stimuli. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Optical fibre dosemeter systems for clinical applications based on radioluminescence and optically stimulated luminescence from Al2O3:C

    DEFF Research Database (Denmark)

    Marckmann, C.J.; Andersen, C.E.; Aznar, M.C.

    2006-01-01

    Optical fibre dosemeter systems based on radioluminescence and optically stimulated luminescence (OSL) from carbon-doped aluminium oxide (Al2O3:C) crystals were developed for in vivo real-time dose rate and absorbed dose measurements in radiotherapy and mammography. A technique was also developed...... for making ultra-small dosemeter probes that can easily be placed inside patients in radiation treatment. These probes have shown excellent properties in both head and neck intensity-modulated radiation therapy treatment and in mammography. The dose-response of the OSL signal for the new optical fibre...

  6. HECTD3 Mediates an HSP90-Dependent Degradation Pathway for Protein Kinase Clients

    Directory of Open Access Journals (Sweden)

    Zhaobo Li

    2017-06-01

    Full Text Available Inhibition of the ATPase cycle of the HSP90 chaperone promotes ubiquitylation and proteasomal degradation of its client proteins, which include many oncogenic protein kinases. This provides the rationale for HSP90 inhibitors as cancer therapeutics. However, the mechanism by which HSP90 ATPase inhibition triggers ubiquitylation is not understood, and the E3 ubiquitin ligases involved are largely unknown. Using a siRNA screen, we have identified components of two independent degradation pathways for the HSP90 client kinase CRAF. The first requires CUL5, Elongin B, and Elongin C, while the second requires the E3 ligase HECTD3, which is also involved in the degradation of MASTL and LKB1. HECTD3 associates with HSP90 and CRAF in cells via its N-terminal DOC domain, which is mutationally disrupted in tumor cells with activated MAP kinase signaling. Our data implicate HECTD3 as a tumor suppressor modulating the activity of this important oncogenic signaling pathway.

  7. Hsp90 as a Gatekeeper of Tumor Angiogenesis: Clinical Promise and Potential Pitfalls

    Directory of Open Access Journals (Sweden)

    J. E. Bohonowych

    2010-01-01

    Full Text Available Tumor vascularization is an essential modulator of early tumor growth, progression, and therapeutic outcome. Although antiangiogenic treatments appear promising, intrinsic and acquired tumor resistance contributes to treatment failure. Clinical inhibition of the molecular chaperone heat shock protein 90 (Hsp90 provides an opportunity to target multiple aspects of this signaling resiliency, which may elicit more robust and enduring tumor repression relative to effects elicited by specifically targeted agents. This review highlights several primary effectors of angiogenesis modulated by Hsp90 and describes the clinical challenges posed by the redundant circuitry of these pathways. The four main topics addressed include (1 Hsp90-mediated regulation of HIF/VEGF signaling, (2 chaperone-dependent regulation of HIF-independent VEGF-mediated angiogenesis, (3 Hsp90-dependent targeting of key proangiogenic receptor tyrosine kinases and modulation of drug resistance, and (4 consideration of factors such as tumor microenvironment that pose several challenges for the clinical efficacy of anti-angiogenic therapy and Hsp90-targeted strategies.

  8. Activation of Hsp90 Enzymatic Activity and Conformational Dynamics through Rationally Designed Allosteric Ligands.

    Science.gov (United States)

    Sattin, Sara; Tao, Jiahui; Vettoretti, Gerolamo; Moroni, Elisabetta; Pennati, Marzia; Lopergolo, Alessia; Morelli, Laura; Bugatti, Antonella; Zuehlke, Abbey; Moses, Mike; Prince, Thomas; Kijima, Toshiki; Beebe, Kristin; Rusnati, Marco; Neckers, Len; Zaffaroni, Nadia; Agard, David A; Bernardi, Anna; Colombo, Giorgio

    2015-09-21

    Hsp90 is a molecular chaperone of pivotal importance for multiple cell pathways. ATP-regulated internal dynamics are critical for its function and current pharmacological approaches block the chaperone with ATP-competitive inhibitors. Herein, a general approach to perturb Hsp90 through design of new allosteric ligands aimed at modulating its functional dynamics is proposed. Based on the characterization of a first set of 2-phenylbenzofurans showing stimulatory effects on Hsp90 ATPase and conformational dynamics, new ligands were developed that activate Hsp90 by targeting an allosteric site, located 65 Å from the active site. Specifically, analysis of protein responses to first-generation activators was exploited to guide the design of novel derivatives with improved ability to stimulate ATP hydrolysis. The molecules' effects on Hsp90 enzymatic, conformational, co-chaperone and client-binding properties were characterized through biochemical, biophysical and cellular approaches. These designed probes act as allosteric activators of the chaperone and affect the viability of cancer cell lines for which proper functioning of Hsp90 is necessary. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Increased HSF activation in muscles with a high constitutive Hsp70 expression

    OpenAIRE

    Locke, Marius; Tanguay, Robert M.

    1996-01-01

    Stress-induced transcriptional regulation of the Hsps is mediated by trimerization and binding of a pre-existing heat shock transcription factor (HSF1) to a specific DNA sequence located in the 5′ region of hsp genes, known as the heat shock element. Hsp70 has been implicated in regulating the activation of the HSF and, according to cell culture models, high steady-state levels of Hsp70 are inversely correlated with HSF activation. To determine if this applies in an intact animal, muscles of ...

  10. Analysis of QUADOS problem on TLD-ALBEDO personal dosemeter responses using discrete ordinates and Monte Carlo methods

    International Nuclear Information System (INIS)

    Kodeli, I.; Tanner, R.

    2005-01-01

    In the scope of QUADOS, a Concerted Action of the European Commission, eight calculational problems were prepared in order to evaluate the use of computational codes for dosimetry in radiation protection and medical physics, and to disseminate 'good practice' throughout the radiation dosimetry community. This paper focuses on the analysis of the P4 problem on the 'TLD-albedo dosemeter: neutron and/or photon response of a four-element TL-dosemeter mounted on a standard ISO slab phantom'. Altogether 17 solutions were received from the participants, 14 of those transported neutrons and 15 photons. Most participants (16 out of 17) used Monte Carlo methods. These calculations are time-consuming, requiring several days of CPU time to perform the whole set of calculations and achieve good statistical precision. The possibility of using deterministic discrete ordinates codes as an alternative to Monte Carlo was therefore investigated and is presented here. In particular the capacity of the adjoint mode calculations is shown. (authors)

  11. Conserved structure and expression of hsp70 paralogs in teleost fishes

    DEFF Research Database (Denmark)

    Metzger, David C.H.; Hansen, Jakob Hemmer; Schulte, Patricia M.

    2016-01-01

    present in the F. heteroclitus genome. Comparison of expression patterns in F. heteroclitus and Gasterosteus aculeatus demonstrates that hsp70-2 has a higher fold increase than hsp70-1 following heat shock in gill but not in muscle tissue, revealing a conserved difference in expression patterns between...

  12. Heat Shock Protein 90 (HSP90 and Her2 in Adenocarcinomas of the Esophagus

    Directory of Open Access Journals (Sweden)

    Julia Slotta-Huspenina

    2014-06-01

    Full Text Available Her2 overexpression and amplification can be found in a significant subset of esophageal adenocarcinomas. The activity of Her2 has been shown to be modulated by molecular chaperones such as HSP90. We analyzed expression/amplification data for HSP90 and Her2 on 127 primary resected esophageal adenocarcinomas in order to evaluate a possible relationship between these two molecules. HSP90 expression determined by immunohistochemistry was observed in various levels. Thirty nine (39 tumors (30.7% were classified as Her2-positive according to their immunoreactivity and amplification status. There was a significant correlation between HSP90 expression and Her2-status (p = 0.008. This could also be demonstrated by quantitative protein expression analysis with reverse phase protein arrays (r = 0.9; p < 0.001. Her2-status was associated withpT-category (p = 0.041, lymph node metastases (p = 0.049 and tumor differentiation (p = 0.036 with a higher percentage of cases with negative Her2 status in lower tumor stagesA negative Her2-status was also associated with better survival in univariate and multivariate analysis (p = 0.001 and p = 0.014. For HSP90, no associations between clinical and pathological parameters were found. The observed association between HSP90 expression and Her2 suggests a co-regulation of these molecules in at least a subset of esophageal adenocarcinomas. Anti-HSP90 drugs, which recently have been introduced in cancer treatment, may also be an option for these tumors by targeting HSP90 alone or in combination with Her2.

  13. Heat Shock Protein 90 (HSP90) and Her2 in Adenocarcinomas of the Esophagus

    Energy Technology Data Exchange (ETDEWEB)

    Slotta-Huspenina, Julia; Becker, Karl-Friedrich [Institute of Pathology, Technische Universität München, München 81765 (Germany); Feith, Marcus [Department of Surgery, Klinikum Rechts der Isar der Technischen Universität München, München 81622 (Germany); Walch, Axel [Institute of Pathology, Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Neuherberg 85764 (Germany); Langer, Rupert, E-mail: rupert.langer@pathology.unibe.ch [Institute of Pathology, University of Bern, Bern 3010 (Switzerland)

    2014-06-27

    Her2 overexpression and amplification can be found in a significant subset of esophageal adenocarcinomas. The activity of Her2 has been shown to be modulated by molecular chaperones such as HSP90. We analyzed expression/amplification data for HSP90 and Her2 on 127 primary resected esophageal adenocarcinomas in order to evaluate a possible relationship between these two molecules. HSP90 expression determined by immunohistochemistry was observed in various levels. Thirty nine (39) tumors (30.7%) were classified as Her2-positive according to their immunoreactivity and amplification status. There was a significant correlation between HSP90 expression and Her2-status (p = 0.008). This could also be demonstrated by quantitative protein expression analysis with reverse phase protein arrays (r = 0.9; p < 0.001). Her2-status was associated withpT-category (p = 0.041), lymph node metastases (p = 0.049) and tumor differentiation (p = 0.036) with a higher percentage of cases with negative Her2 status in lower tumor stagesA negative Her2-status was also associated with better survival in univariate and multivariate analysis (p = 0.001 and p = 0.014). For HSP90, no associations between clinical and pathological parameters were found. The observed association between HSP90 expression and Her2 suggests a co-regulation of these molecules in at least a subset of esophageal adenocarcinomas. Anti-HSP90 drugs, which recently have been introduced in cancer treatment, may also be an option for these tumors by targeting HSP90 alone or in combination with Her2.

  14. Active participation of Hsp90 in the biogenesis of the trimeric reovirus cell attachment protein sigma1.

    Science.gov (United States)

    Gilmore, R; Coffey, M C; Lee, P W

    1998-06-12

    The reovirus cell attachment protein, sigma1, is a lollipop-shaped homotrimer with an N-terminal fibrous tail and a C-terminal globular head. Biogenesis of this protein involves two trimerization events: N-terminal trimerization, which occurs cotranslationally and is Hsp70/ATP-independent, and C-terminal trimerization, which occurs posttranslationally and is Hsp70/ATP-dependent. To determine if Hsp90 also plays a role in sigma1 biogenesis, we analyzed sigma1 synthesized in rabbit reticulocyte lysate. Coprecipitation experiments using anti-Hsp90 antibodies revealed that Hsp90 was associated with immature sigma1 trimers (hydra-like intermediates with assembled N termini and unassembled C termini) but not with mature trimers. The use of truncated sigma1 further demonstrated that only the C-terminal half of sigma1 associated with Hsp90. In the presence of the Hsp90 binding drug geldanamycin, N-terminal trimerization proceeded normally, but C-terminal trimerization was blocked. Geldanamycin did not inhibit the association of Hsp90 with sigma 1 but prevented the subsequent release of Hsp90 from the immature sigma1 complex. We also examined the status of p23, an Hsp90-associated cochaperone. Like Hsp90, p23 only associated with immature sigma1 trimers, and this association was mapped to the C-terminal half of sigma1. However, unlike Hsp90, p23 was released from the sigma1 complex upon the addition of geldanamycin. These results highlight an all-or-none concept of chaperone involvement in different oligomerization domains within a single protein and suggest a possible common usage of chaperones in the regulation of general protein folding and of steroid receptor activation.

  15. Functional analysis of the Hikeshi-like protein and its interaction with HSP70 in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, Shinya; Ohama, Naohiko; Mizoi, Junya [Laboratory of Plant Molecular Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657 (Japan); Shinozaki, Kazuo [RIKEN Plant Science Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045 (Japan); Yamaguchi-Shinozaki, Kazuko, E-mail: akys@mail.ecc.u-tokyo.ac.jp [Laboratory of Plant Molecular Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657 (Japan)

    2014-07-18

    Highlights: • HKL, a Hikeshi homologous gene is identified in Arabidopsis. • HKL interacts with two HSP70 isoforms and regulates the subcellular localization of HSC70-1. • The two HSP70 translocate into nucleus in response to heat stress. • Overexpression of HKL confers thermotolerance in transgenic plants. - Abstract: Heat shock proteins (HSPs) refold damaged proteins and are an essential component of the heat shock response. Previously, the 70 kDa heat shock protein (HSP70) has been reported to translocate into the nucleus in a heat-dependent manner in many organisms. In humans, the heat-induced translocation of HSP70 requires the nuclear carrier protein Hikeshi. In the Arabidopsis genome, only one gene encodes a protein with high homology to Hikeshi, and we named this homolog Hikeshi-like (HKL) protein. In this study, we show that two Arabidopsis HSP70 isoforms accumulate in the nucleus in response to heat shock and that HKL interacts with these HSP70s. Our histochemical analysis revealed that HKL is predominantly expressed in meristematic tissues, suggesting the potential importance of HKL during cell division in Arabidopsis. In addition, we show that HKL regulates HSP70 localization, and HKL overexpression conferred thermotolerance to transgenic Arabidopsis plants. Our results suggest that HKL plays a positive role in the thermotolerance of Arabidopsis plants and cooperatively interacts with HSP70.

  16. HSP90 is essential for Jak-STAT signaling in classical Hodgkin lymphoma cells

    Directory of Open Access Journals (Sweden)

    Kube Dieter

    2009-07-01

    Full Text Available Abstract In classical Hodgkin lymphoma (cHL chemotherapeutic regimens are associated with stagnant rates of secondary malignancies requiring the development of new therapeutic strategies. We and others have shown that permanently activated Signal Transducer and Activator of Transcription (STAT molecules are essential for cHL cells. Recently an overexpression of heat-shock protein 90 (HSP90 in cHL cells has been shown and inhibition of HSP90 seems to affect cHL cell survival. Here we analysed the effects of HSP90 inhibition by geldanamycin derivative 17-AAG or RNA interference (RNAi on aberrant Jak-STAT signaling in cHL cells. Treatment of cHL cell lines with 17-AAG led to reduced cell proliferation and a complete inhibition of STAT1, -3, -5 and -6 tyrosine phosphorylation probably as a result of reduced protein expression of Janus kinases (Jaks. RNAi-mediated inhibition of HSP90 showed similar effects on Jak-STAT signaling in L428 cHL cells. These results suggest a central role of HSP90 in permanently activated Jak-STAT signaling in cHL cells. Therapeutics targeting HSP90 may be a promising strategy in cHL and other cancer entities associated with deregulated Jak-STAT pathway activation.

  17. Preliminary X-Ray Crystallographic Studies of the N-Terminal Domains of Hsp104 from Yeast Candida albicans and Saccharomyces cerevisiae

    Science.gov (United States)

    Wang, P.; Li, J.; Sha, B.

    2017-12-01

    Yeast Hsp104 is an ATP-dependent molecular chaperone, which can solublize and rescue denatured proteins from aggregates into active form by cooperating with Hsp70 and Hsp40 chaperones. Moreover, overexpression of Hsp104 of Saccharomyces cerevisiae (ScHsp104) cures the yeast [ PSI +] prion due to the completely dissolution of the prion seeds, demonstrating ScHsp104's potential to clear amyloid-like protein aggregates, thus making ScHsp104 a promising medication approach for human amyloidogenic neurodegenerative diseases. Because the working mechanisms for ScHsp104's activities have not been clearly elucidated yet, crystallographic determination of ScHsp104 stands for great significance. Here, the expression, purification and crystallization of the N-terminal domains of Hsp104 from yeast Candida albicans (CaHsp104N) and S. cerevisiae (ScHsp104N) are described. The CaHsp104N crystals diffracted to 1.54 Å and belonged to the sp. gr. P3221 or P3121, with unit cell parameters of a = 55.213 Å, c = 109.451 Å. The data of the ScHsp104N crystals were collected to the resolution of 2.53 Å in the sp. gr. C2, with unit cell parameters a = 148.587 Å, b = 66.255 Å, c = 74.577 Å, β = 107.369°. The phase of ScHsp104N is determined by the molecular replacement method using CaHsp104N as the search model.

  18. In Vivo Detection of HSP90 Identifies Breast Cancers with Aggressive Behavior.

    Science.gov (United States)

    Osada, Takuya; Kaneko, Kensuke; Gwin, William R; Morse, Michael A; Hobeika, Amy; Pogue, Brian W; Hartman, Zachary C; Hughes, Philip F; Haystead, Timothy; Lyerly, H Kim

    2017-12-15

    Purpose: Hsp90, a chaperone to numerous molecular pathways in malignant cells, is elevated in aggressive breast cancers. We hypothesized that identifying breast cells with elevated Hsp90 activity in situ could result in early detection of aggressive breast cancers. Experimental Design: We exploited the uptake of an Hsp90 inhibitor by malignant cells to create an imaging probe (HS131) of Hsp90 activity by linking it to a near-infrared (nIR) dye. HS131 uptake into cells correlated with cell membrane expression of Hsp90 and was used to image molecular subtypes of murine and human breast cancers in vitro and in murine models. Results: HS131 imaging was both sensitive and specific in detecting the murine 4T1 breast cancer cell line, as well as subclones with differing metastatic potential. Highly metastatic subclones (4T07) had high HS131 uptake, but subclones with lower metastatic potential (67NR, 168FARN) had low HS131 uptake. We generated isogenic cell lines to demonstrate that overexpression of a variety of specific oncogenes resulted in high HS131 uptake and retention. Finally, we demonstrated that HS131 could be used to detect spontaneous tumors in MMTV-neu mice, as well as primary and metastatic human breast cancer xenografts. HS131 could image invasive lobular breast cancer, a histologic subtype of breast cancer which is often undetectable by mammography. Conclusions: An HSP90-targeting nIR probe is sensitive and specific in imaging all molecular subtypes of murine and human breast cancer, with higher uptake in aggressive and highly metastatic clones. Clinical studies with Hsp90-targeting nIR probes will be initiated shortly. Clin Cancer Res; 23(24); 7531-42. ©2017 AACR . ©2017 American Association for Cancer Research.

  19. Administration of M. leprae Hsp65 interferes with the murine lupus progression.

    Directory of Open Access Journals (Sweden)

    Eliana B Marengo

    Full Text Available The heat shock protein [Hsp] family guides several steps during protein synthesis, are abundant in prokaryotic and eukaryotic cells, and are highly conserved during evolution. The Hsp60 family is involved in assembly and transport of proteins, and is expressed at very high levels during autoimmunity or autoinflammatory phenomena. Here, the pathophysiological role of the wild type [WT] and the point mutated K(409A recombinant Hsp65 of M. leprae in an animal model of Systemic Lupus Erythematosus [SLE] was evaluated in vivo using the genetically homogeneous [NZBxNZW]F(1 mice. Anti-DNA and anti-Hsp65 antibodies responsiveness was individually measured during the animal's life span, and the mean survival time [MST] was determined. The treatment with WT abbreviates the MST in 46%, when compared to non-treated mice [p<0.001]. An increase in the IgG2a/IgG1 anti-DNA antibodies ratio was also observed in animals injected with the WT Hsp65. Incubation of BALB/c macrophages with F(1 serum from WT treated mice resulted in acute cell necrosis; treatment of these cells with serum from K(409A treated mice did not cause any toxic effect. Moreover, the involvement of WT correlates with age and is dose-dependent. Our data suggest that Hsp65 may be a central molecule intervening in the progression of the SLE, and that the point mutated K(409A recombinant immunogenic molecule, that counteracts the deleterious effect of WT, may act mitigating and delaying the development of SLE in treated mice. This study gives new insights into the general biological role of Hsp and the significant impact of environmental factors during the pathogenesis of this autoimmune process.

  20. Bio energy: Bio fuel - Properties and Production

    International Nuclear Information System (INIS)

    Wilhelmsen, Gunnar; Martinsen, Arnold Kyrre; Sandberg, Eiliv; Fladset, Per Olav; Kjerschow, Einar; Teslo, Einar

    2001-01-01

    This is Chapter 3 of the book ''Bio energy - Environment, technique and market''. Its main sections are: (1) Definitions and properties, (2) Bio fuel from the forest, (3) Processed bio fuel - briquettes, pellets and powder, (4) Bio fuel from agriculture, (5) Bio fuel from agro industry, (6) Bio fuel from lakes and sea, (7) Bio fuel from aquaculture, (8) Bio fuel from wastes and (9) Hydrogen as a fuel. The exposition largely describes the conditions in Norway. The chapter on energy from the forest includes products from the timber and sawmill industry, the pulp and paper industry, furniture factories etc. Among agricultural sources are straw, energy forests, vegetable oil, bio ethanol, manure

  1. Identification of the plant compound geraniin as a novel Hsp90 inhibitor.

    Directory of Open Access Journals (Sweden)

    Antonio Vassallo

    Full Text Available Besides its function in normal cellular growth, the molecular chaperone heat shock protein 90 (Hsp90 binds to a large number of client proteins required for promoting cancer cell growth and/or survival. In an effort to discover new small molecules able to inhibit the Hsp90 ATPase and chaperoning activities, we screened, by a surface plasmon resonance assay, a small library including different plant polyphenols. The ellagitannin geraniin, was identified as the most promising molecule, showing a binding affinity to Hsp90α similar to that of 17-(allylamino-17-demethoxygeldanamycin (17AGG. Geraniin was able to inhibit in vitro the Hsp90α ATPase activity in a dose-dependent manner, with an inhibitory efficiency comparable to that measured for 17-AAG. In addition, this compound compromised the chaperone activity of Hsp90α, monitored by the citrate synthase thermal induced aggregation assay. Geraniin decreased the viability of HeLa and Jurkat cell lines and caused an arrest in G2/M phase. We also proved that following exposure to different concentrations of geraniin, the level of expression of the client proteins c-Raf, pAkt, and EGFR was strongly down-regulated in both the cell lines. These results, along with the finding that geraniin did not exert any appreciable cytotoxicity on normal cells, encourage further studies on this compound as a promising chemical scaffold for the design of new Hsp90 inhibitors.

  2. Essential oil from Cymbopogon flexuosus as the potential inhibitor for HSP90.

    Science.gov (United States)

    Gaonkar, Roopa; Shiralgi, Yallappa; Lakkappa, Dhananjaya B; Hegde, Gurumurthy

    2018-01-01

    The essential oil of Cymbopogon flexuosus or lemongrass oil (LO) is reported to have antibacterial, antifungal and anticancerous effects. HSP90 is one of the major chaperones responsible for the proper folding of cancer proteins. In this paper we show that the essential oil of C. flexuosus significantly suppresses the HSP90 gene expression. The cytotoxicity of the compounds was tested by MTT assay and the gene expression studies were carried out using HEK-293 and MCF-7 cells. Also we tested the efficacy of the major component of this essential oil viz. citral and geraniol in inhibiting the HSP90 expression. The oil was found to be more cytotoxic to MCF-7 cells with different IC 50 values for the oil (69.33 μg/mL), citral (140.7 μg/mL) and geraniol (117 μg/mL). The fold change of expression was calculated by RT-qPCR using ΔΔCt (2 ^-ΔΔCt ) method and it was 0.1 and 0.03 in MCF-7 cells at 80 μg/mL and 160 μg/mL of LO. Western blot results showed suppression of HSP90 protein expression and HSP90 - ATPase activity inhibition was also observed using LO. This study shows the anticancer mechanism exhibited by the essential oil of C. flexuosus is by the inhibition of the important chaperone protein HSP90.

  3. Contribution to the development study of a personal fast neutron dosemeter using nuclear emulsion

    International Nuclear Information System (INIS)

    Ott, C.

    1985-02-01

    This work deals with the response of a personal neutron dosemeter using nuclear emulsion. The main characteristics of the detector are studied with the help of a computer programme simulating the conditions of the formation of recoil protons tracks recorded by nuclear emulsions. The lecture limits of nuclear emulsions with light microscope and the validity of our computer code are checked by comparing our theoretical values with experimental results [fr

  4. Role of Subunit Exchange and Electrostatic Interactions on the Chaperone Activity of Mycobacterium leprae HSP18

    Science.gov (United States)

    Nandi, Sandip Kumar; Panda, Alok Kumar; Chakraborty, Ayon; Ray, Sougata Sinha; Biswas, Ashis

    2015-01-01

    Mycobacterium leprae HSP18, a major immunodominant antigen of M. leprae pathogen, is a small heat shock protein. Previously, we reported that HSP18 is a molecular chaperone that prevents aggregation of different chemically and thermally stressed client proteins and assists refolding of denatured enzyme at normal temperature. We also demonstrated that it can efficiently prevent the thermal killing of E. coli at higher temperature. However, molecular mechanism behind the chaperone function of HSP18 is still unclear. Therefore, we studied the structure and chaperone function of HSP18 at normal temperature (25°C) as well as at higher temperatures (31–43°C). Our study revealed that the chaperone function of HSP18 is enhanced significantly with increasing temperature. Far- and near-UV CD experiments suggested that its secondary and tertiary structure remain intact in this temperature range (25–43°C). Besides, temperature has no effect on the static oligomeric size of this protein. Subunit exchange study demonstrated that subunits of HSP18 exchange at 25°C with a rate constant of 0.018 min-1. Both rate of subunit exchange and chaperone activity of HSP18 is found to increase with rise in temperature. However, the surface hydrophobicity of HSP18 decreases markedly upon heating and has no correlation with its chaperone function in this temperature range. Furthermore, we observed that HSP18 exhibits diminished chaperone function in the presence of NaCl at 25°C. At elevated temperatures, weakening of interactions between HSP18 and stressed client proteins in the presence of NaCl results in greater reduction of its chaperone function. The oligomeric size, rate of subunit exchange and structural stability of HSP18 were also found to decrease when electrostatic interactions were weakened. These results clearly indicated that subunit exchange and electrostatic interactions play a major role in the chaperone function of HSP18. PMID:26098662

  5. Role of Subunit Exchange and Electrostatic Interactions on the Chaperone Activity of Mycobacterium leprae HSP18.

    Science.gov (United States)

    Nandi, Sandip Kumar; Panda, Alok Kumar; Chakraborty, Ayon; Sinha Ray, Sougata; Biswas, Ashis

    2015-01-01

    Mycobacterium leprae HSP18, a major immunodominant antigen of M. leprae pathogen, is a small heat shock protein. Previously, we reported that HSP18 is a molecular chaperone that prevents aggregation of different chemically and thermally stressed client proteins and assists refolding of denatured enzyme at normal temperature. We also demonstrated that it can efficiently prevent the thermal killing of E. coli at higher temperature. However, molecular mechanism behind the chaperone function of HSP18 is still unclear. Therefore, we studied the structure and chaperone function of HSP18 at normal temperature (25°C) as well as at higher temperatures (31-43°C). Our study revealed that the chaperone function of HSP18 is enhanced significantly with increasing temperature. Far- and near-UV CD experiments suggested that its secondary and tertiary structure remain intact in this temperature range (25-43°C). Besides, temperature has no effect on the static oligomeric size of this protein. Subunit exchange study demonstrated that subunits of HSP18 exchange at 25°C with a rate constant of 0.018 min(-1). Both rate of subunit exchange and chaperone activity of HSP18 is found to increase with rise in temperature. However, the surface hydrophobicity of HSP18 decreases markedly upon heating and has no correlation with its chaperone function in this temperature range. Furthermore, we observed that HSP18 exhibits diminished chaperone function in the presence of NaCl at 25°C. At elevated temperatures, weakening of interactions between HSP18 and stressed client proteins in the presence of NaCl results in greater reduction of its chaperone function. The oligomeric size, rate of subunit exchange and structural stability of HSP18 were also found to decrease when electrostatic interactions were weakened. These results clearly indicated that subunit exchange and electrostatic interactions play a major role in the chaperone function of HSP18.

  6. Sensitization of multidrug-resistant human cancer cells to Hsp90 inhibitors by down-regulation of SIRT1

    Science.gov (United States)

    Kim, Hak-Bong; Lee, Su-Hoon; Um, Jee-Hyun; Oh, Won Keun; Kim, Dong-Wan; Kang, Chi-Dug; Kim, Sun-Hee

    2015-01-01

    The effectiveness of Hsp90 inhibitors as anticancer agents was limited in multidrug-resistant (MDR) human cancer cells due to induction of heat shock proteins (Hsps) such as Hsp70/Hsp27 and P-glycoprotein (P-gp)-mediated efflux. In the present study, we showed that resistance to Hsp90 inhibitors of MDR human cancer cells could be overcome with SIRT1 inhibition. SIRT1 knock-down or SIRT1 inhibitors (amurensin G and EX527) effectively suppressed the resistance to Hsp90 inhibitors (17-AAG and AUY922) in several MDR variants of human lymphoblastic leukemia and human breast cancer cell lines. SIRT1 inhibition down-regulated the expression of heat shock factor 1 (HSF1) and subsequently Hsps and facilitated Hsp90 multichaperone complex disruption via hyperacetylation of Hsp90/Hsp70. These findings were followed by acceleration of ubiquitin ligase CHIP-mediated mutant p53 (mut p53) degradation and subsequent down-regulation of P-gp in 17-AAG-treated MDR cancer cells expressing P-gp and mut p53 after inhibition of SIRT1. Therefore, combined treatment with Hsp90 inhibitor and SIRT1 inhibitor could be a more effective therapeutic approach for Hsp90 inhibitor-resistant MDR cells via down-regulation of HSF1/Hsps, mut p53 and P-gp. PMID:26416354

  7. Association of HSP70 and its co-chaperones with Alzheimer's disease

    NARCIS (Netherlands)

    L. Broer (Linda); M.A. Ikram (Arfan); M. Schuur (Maaike); A.L. DeStefano (Anita); J.C. Bis (Joshua); F. Liu (Fan); F. Rivadeneira Ramirez (Fernando); A.G. Uitterlinden (André); A. Beiser (Alexa); W.T. Longstreth Jr; A. Hofman (Albert); Y.S. Aulchenko (Yurii); S. Seshadri (Sudha); A.L. Fitzpatrick (Annette); B.A. Oostra (Ben); M.M.B. Breteler (Monique); P. Tikka-Kleemola (Päivi)

    2011-01-01

    textabstractThe heat shock protein (HSP) 70 family has been implicated in the pathology of Alzheimer's disease (AD). In this study, we examined common genetic variations in the 80 genes encoding HSP70 and its co-chaperones. We conducted a study in a series of 462 patients and 5238 unaffected

  8. Cloning and Expression of HSP of Taenia Solium Oncosphere%猪带绦虫六钩蚴 HSP 的克隆和表达

    Institute of Scientific and Technical Information of China (English)

    王哲; 赵权

    2013-01-01

      The HSP gene was separately amplified from total RNA of activated Taenia solium oncosphere by RT -PCR.The PCR products were cloned into pGH vector,recombinant positive clones was sequenced after restriction enzyme digestion.The HSP gene was subcloned into pET28a expression vector,the recombinant pET28a-HSP infected into E.coliBL21.IPTG was added to induce fusion expression and the expression products was identified by SDS-PAGE and Western-blot.One fusion protein band about 35 kDa was identified by SDS -PAGE after inducible expression after inducible expression,The result would lay foundations for the mechanism of invasion of between oncosphere and host,and the design of new vaccine anti-porcine cysticercosis and taeniasis.%  提取猪带绦虫激活和未激活六钩蚴总 RNA,RT-PCR 扩增 HSP 目的基因,将目的基因与 pGH 克隆载体连接,经酶切鉴定后,将阳性重组质粒进行测序,结果扩增出激活的六钩蚴的目的片段。将目的基因亚克隆到原核表达载体 pET-28a-HSP中,并将获得的 pET28a-HSP 阳性重组子转化至宿主菌 E.coliBL21,IPTG 进行诱导表达,并对重组抗原 pET-28a-HSP 进行SDS-PAGE 和 Western-blot 检测。结果表明重组经 SDS-PAGE 分析可见一条约35 kDa 大小的融合蛋白条带的抗原,Western-blot 结果显示其能被囊虫病人阳性血清识别。这将为进一步阐明六钩蚴入侵中间宿主的机理、设计新型抗猪囊虫病和绦虫病疫苗打下基础。

  9. Heat and exercise acclimation increases intracellular levels of Hsp72 and inhibits exercise-induced increase in intracellular and plasma Hsp72 in humans.

    Science.gov (United States)

    Magalhães, Flávio de Castro; Amorim, Fabiano Trigueiro; Passos, Renata L Freitas; Fonseca, Michele Atalla; Oliveira, Kenya Paula Moreira; Lima, Milene Rodrigues Malheiros; Guimarães, Juliana Bohen; Ferreira-Júnior, João Batista; Martini, Angelo R P; Lima, Nilo R V; Soares, Danusa Dias; Oliveira, Edilamar Menezes; Rodrigues, Luiz Oswaldo Carneiro

    2010-11-01

    In order to verify the effects of heat and exercise acclimation (HA) on resting and exercise-induced expression of plasma and leukocyte heat shock protein 72 (Hsp72) in humans, nine healthy young male volunteers (25.0 ± 0.7 years; 80.5 ± 2.0 kg; 180 ± 2 cm, mean ± SE) exercised for 60 min in a hot, dry environment (40 ± 0°C and 45 ± 0% relative humidity) for 11 days. The protocol consisted of running on a treadmill using a controlled hyperthermia technique in which the work rate was adjusted to elevate the rectal temperature by 1°C in 30 min and maintain it elevated for another 30 min. Before and after the HA, the volunteers performed a heat stress test (HST) at 50% of their individual maximal power output for 90 min in the same environment. Blood was drawn before (REST), immediately after (POST) and 1 h after (1 h POST) HST, and plasma and leukocytes were separated and stored. Subjects showed expected adaptations to HA: reduced exercise rectal and mean skin temperatures and heart rate, and augmented sweat rate and exercise tolerance. In HST1, plasma Hsp72 increased from REST to POST and then returned to resting values 1 h POST (REST: 1.11 ± 0.07, POST: 1.48 ± 0.10, 1 h POST: 1.22 ± 0.11 ng mL(-1); p  0.05). HA increased resting levels of intracellular Hsp72 (HST1: 1 ± 0.02 and HST2: 4.2 ± 1.2 density units, p  0.05). Regression analysis showed that the lower the pre-exercise expression of intracellular Hsp72, the higher the exercise-induced increase (R = -0.85, p < 0.05). In conclusion, HA increased resting leukocyte Hsp72 levels and inhibited exercise-induced expression. This intracellular adaptation probably induces thermotolerance. In addition, the non-increase in plasma Hsp72 after HA may be related to lower stress at the cellular level in the acclimated individuals.

  10. Cryptic variation in morphological evolution: HSP90 as a capacitor for loss of eyes in cavefish.

    Science.gov (United States)

    Rohner, Nicolas; Jarosz, Dan F; Kowalko, Johanna E; Yoshizawa, Masato; Jeffery, William R; Borowsky, Richard L; Lindquist, Susan; Tabin, Clifford J

    2013-12-13

    In the process of morphological evolution, the extent to which cryptic, preexisting variation provides a substrate for natural selection has been controversial. We provide evidence that heat shock protein 90 (HSP90) phenotypically masks standing eye-size variation in surface populations of the cavefish Astyanax mexicanus. This variation is exposed by HSP90 inhibition and can be selected for, ultimately yielding a reduced-eye phenotype even in the presence of full HSP90 activity. Raising surface fish under conditions found in caves taxes the HSP90 system, unmasking the same phenotypic variation as does direct inhibition of HSP90. These results suggest that cryptic variation played a role in the evolution of eye loss in cavefish and provide the first evidence for HSP90 as a capacitor for morphological evolution in a natural setting.

  11. The Exported Chaperone PfHsp70x Is Dispensable for the Plasmodium falciparum Intraerythrocytic Life Cycle.

    Science.gov (United States)

    Cobb, David W; Florentin, Anat; Fierro, Manuel A; Krakowiak, Michelle; Moore, Julie M; Muralidharan, Vasant

    2017-01-01

    Export of parasite proteins into the host erythrocyte is essential for survival of Plasmodium falciparum during its asexual life cycle. While several studies described key factors within the parasite that are involved in protein export, the mechanisms employed to traffic exported proteins within the host cell are currently unknown. Members of the Hsp70 family of chaperones, together with their Hsp40 cochaperones, facilitate protein trafficking in other organisms, and are thus likely used by P. falciparum in the trafficking of its exported proteins. A large group of Hsp40 proteins is encoded by the parasite and exported to the host cell, but only one Hsp70, P. falciparum Hsp70x (PfHsp70x), is exported with them. PfHsp70x is absent in most Plasmodium species and is found only in P. falciparum and closely related species that infect apes. Herein, we have utilized clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 genome editing in P. falciparum to investigate the essentiality of PfHsp70x. We show that parasitic growth was unaffected by knockdown of PfHsp70x using both the dihydrofolate reductase (DHFR)-based destabilization domain and the glmS ribozyme system. Similarly, a complete gene knockout of PfHsp70x did not affect the ability of P. falciparum to proceed through its intraerythrocytic life cycle. The effect of PfHsp70x knockdown/knockout on the export of proteins to the host red blood cell (RBC), including the critical virulence factor P. falciparum erythrocyte membrane protein 1 (PfEMP1), was tested, and we found that this process was unaffected. These data show that although PfHsp70x is the sole exported Hsp70, it is not essential for the asexual development of P. falciparum . IMPORTANCE Half of the world's population lives at risk for malaria. The intraerythrocytic life cycle of Plasmodium spp. is responsible for clinical manifestations of malaria; therefore, knowledge of the parasite's ability to survive within the erythrocyte is

  12. Photon energy dependence of three fortuitous dosemeters from personal electronic devices, measured by optically stimulated luminescence

    International Nuclear Information System (INIS)

    Beerten, K.; Vanhavere, F.

    2010-01-01

    New data are presented with regard to the relative OSL sensitivity of three different emergency dosemeters irradiated to various photon energies approximately between 48 and 1250 keV using blue excitation light. Investigated components extracted from commonly worn objects include those from USB flash drives (alumina substrate), mobile phones (Ba-rich silicate) and credit cards (chip card module). Several basic properties have been investigated such as the overall radiation sensitivity, the shape of the decay curve and fading of the OSL signal. An increase of the sensitivity for low energies relative to 60 Co gamma rays can be observed for the three dosemeters, the increase being very pronounced for the Ba-rich component (factor of 10) and less pronounced for the chip card module (factor of 2). It is concluded that proper dose correction factors for photon energy have to be applied in order to accurately determine the absorbed dose to tissue. The OSL sensitivity to neutron irradiation was investigated as well, but this was found to be less than the gamma sensitivity. (authors)

  13. Photon energy dependence of three fortuitous dosemeters from personal electronic devices, measured by optically stimulated luminescence.

    Science.gov (United States)

    Beerten, Koen; Vanhavere, Filip

    2010-08-01

    New data are presented with regard to the relative OSL sensitivity of three different emergency dosemeters irradiated to various photon energies approximately between 48 and 1250 keV using blue excitation light. Investigated components extracted from commonly worn objects include those from USB flash drives (alumina substrate), mobile phones (Ba-rich silicate) and credit cards (chip card module). Several basic properties have been investigated such as the overall radiation sensitivity, the shape of the decay curve and fading of the OSL signal. An increase of the sensitivity for low energies relative to (60)Co gamma rays can be observed for the three dosemeters, the increase being very pronounced for the Ba-rich component (factor of 10) and less pronounced for the chip card module (factor of 2). It is concluded that proper dose correction factors for photon energy have to be applied in order to accurately determine the absorbed dose to tissue. The OSL sensitivity to neutron irradiation was investigated as well, but this was found to be less than the gamma sensitivity.

  14. Development of a fibre-optic dosemeter to measure the skin dose and percentage depth dose in the build-up region of therapeutic photon beams

    International Nuclear Information System (INIS)

    Kim, K. A.; Yoo, W. J.; Jang, K. W.; Moon, J.; Han, K. T.; Jeon, D.; Park, J. Y.; Cha, E. J.; Lee, B.

    2013-01-01

    In this study, a fibre-optic dosemeter (FOD) using an organic scintillator with a diameter of 0.5 mm for photon-beam therapy dosimetry was fabricated. The fabricated dosemeter has many advantages, including water equivalence, high spatial resolution, remote sensing and real-time measurement. The scintillating light generated from an organic-dosemeter probe embedded in a solid-water stack phantom is guided to a photomultiplier tube and an electrometer via 20 m of plastic optical fibre. Using this FOD, the skin dose and the percentage depth dose in the build-up region according to the depths of a solid-water stack phantom are measured with 6- and 15-MV photon-beam energies with field sizes of 10310 and 20320 cm 2 , respectively. The results are compared with those measured using conventional dosimetry films. It is expected that the proposed FOD can be effectively used in radiotherapy dosimetry for accurate measurement of the skin dose and the depth dose distribution in the build-up region due to its high spatial resolution. (authors)

  15. Heat shock protein 90 (Hsp90) chaperone complex. A molecular target for enhancement of thermosensitivity and radiosensitivity

    International Nuclear Information System (INIS)

    Akimoto, Tetsuo; Nonaka, Tetsuo; Kitamoto, Yoshizumi; Sakurai, Hideyuki

    2002-01-01

    Heat shock protein 90 (Hsp90) is a highly conserved heat shock protein in animal and plants, and exists abundantly in the cytoplasm in unstressed condition, accounting for 1-2% in cytoplasmic proteins. Main difference of Hsp90 from other Hsps are its substrate that Hsp90 binds to. These substrates include various signal transduction proteins, kinase, steroid receptors and transcription factors, therefore, Hsp90 plays a key role in maintaining cellular signal transduction networks. Many chaperoned proteins (client proteins) of Hsp90 are associated with cellular proliferation or malignant transformation, thus Hsp90 chaperone complex has been focused as targets for cancer therapy. Among the client proteins, there are several molecules that have been defined as targets or factors for determination or enhancement of radiosensitivity or thermosensitivity. Thus, it is easily speculated that Hsp90 chaperone complex inhibitors that disrupt association of Hsp90 and client protein in combination with radiation or/and heat has potential effect on enhancement of radiosensitivity or thermosensitivity. In this paper, possible mechanisms in enhancing radiosensitivity or thermosensitivity according to the client proteins will be summarized. (author)

  16. Ubiquitin-fusion degradation pathway: A new strategy for inducing CD8 cells specific for mycobacterial HSP65

    International Nuclear Information System (INIS)

    Shen Jianying; Hisaeda, Hajime; Chou Bin; Yu Qingsheng; Tu Liping; Himeno, Kunisuke

    2008-01-01

    The ubiquitin-proteasome system (UPS) plays an indispensable role in inducing MHC class I-restricted CD8 + T cells. In this study, we exploited UPS to induce CD8 + T cells specific for mycobacterial HSP65 (mHSP65), one of the leading vaccine candidates against infection with Mycobacterium tuberculosis. A chimeric DNA termed pU-HSP65 encoding a fusion protein between murine ubiquitin and mHSP65 was constructed, and C57BL/6 (B6) mice were immunized with the DNA using gene gun bombardment. Mice immunized with the chimeric DNA acquired potent resistance against challenge with the syngeneic B16F1 melanoma cells transfected with the mHSP65 gene (HSP65/B16F1), compared with those immunized with DNA encoding only mHSP65. Splenocytes from the former group of mice showed a higher grade of cytotoxic activity against HSP65/B16F1 cells and contained a larger number of granzyme B- or IFN-γ-producing CD8 + T cells compared with those from the latter group of mice

  17. Three-dimensional absorbed dose determinations by N.M.R. analysis of phantom-dosemeters

    International Nuclear Information System (INIS)

    Gambarini, G.; Birattari, C.; Fumagalli, M.L.; Vai, A.; Monti, D.; Salvadori, P.; Facchielli, L.; Sichirollo, A.E.

    1996-01-01

    Magnetic resonance imaging of a tissue-equivalent phantom is a promising technique for three-dimensional determination of absorbed dose from ionizing radiation. A reliable method of determining the spatial distribution of absorbed dose is indispensable for the planning of treatment in the presently developed radiotherapy techniques aimed at obtaining high energy selectively delivered to cancerous tissues, with low dose delivered to the surrounding healthy tissue. Aqueous gels infused with the Fricke dosemeter (i.e. with a ferrous sulphate solution), as proposed in 1984 by Gore et al., have shown interesting characteristics and, in spite of some drawbacks that cause a few limitations to their utilisation, they have shown the feasibility of three-dimensional dose determinations by nuclear magnetic resonance (NMR) imaging. Fricke-infused agarose gels with various compositions have been analysed, considering the requirements of the new radiotherapy techniques, in particular Boron Neutron Capture Therapy (B.N.C.T.) and proton therapy. Special attention was paid to obtain good tissue equivalence for every radiation type of interest. In particular, the tissue equivalence for thermal neutrons, which is a not simple problem, has also been satisfactorily attained. The responses of gel-dosemeters having the various chosen compositions have been analysed, by mean of NMR instrumentation. Spectrophotometric measurements have also been performed, to verify the consistence of the results. (author)

  18. Plasmodial Hsp70s are functionally adapted to the malaria parasite life cycle

    Directory of Open Access Journals (Sweden)

    Jude M Przyborski

    2015-06-01

    Full Text Available The human malaria parasite, Plasmodium falciparum, encodes a minimal complement of six heat shock protein 70s (PfHSP70s, some of which are highly expressed and are thought to play an important role in the survival and pathology of the parasite. In addition to canonical features of molecular chaperones, these HSP70s possess properties that reflect functional adaptation to a parasitic life style, including resistance to thermal insult during fever periods and host-parasite interactions. The parasite even exports an HSP70 to the host cell where it is likely to be involved in host cell modification. This review focuses on the features of the PfHSP70s, particularly with respect to their adaptation to the malaria parasite life cycle.

  19. Quantitative analysis of the interplay between hsc70 and its co-chaperone HspBP1

    Directory of Open Access Journals (Sweden)

    Hicham Mahboubi

    2015-12-01

    Full Text Available Background. Chaperones and their co-factors are components of a cellular network; they collaborate to maintain proteostasis under normal and harmful conditions. In particular, hsp70 family members and their co-chaperones are essential to repair damaged proteins. Co-chaperones are present in different subcellular compartments, where they modulate chaperone activities.Methods and Results. Our studies assessed the relationship between hsc70 and its co-factor HspBP1 in human cancer cells. HspBP1 promotes nucleotide exchange on hsc70, but has also chaperone-independent functions. We characterized the interplay between hsc70 and HspBP1 by quantitative confocal microscopy combined with automated image analyses and statistical evaluation. Stress and the recovery from insult changed significantly the subcellular distribution of hsc70, but had little effect on HspBP1. Single-cell measurements and regression analysis revealed that the links between the chaperone and its co-factor relied on (i the physiological state of the cell and (ii the subcellular compartment. As such, we identified a linear relationship and strong correlation between hsc70 and HspBP1 distribution in control and heat-shocked cells; this correlation changed in a compartment-specific fashion during the recovery from stress. Furthermore, we uncovered significant stress-induced changes in the colocalization between hsc70 and HspBP1 in the nucleus and cytoplasm.Discussion. Our quantitative approach defined novel properties of the co-chaperone HspBP1 as they relate to its interplay with hsc70. We propose that changes in cell physiology promote chaperone redistribution and thereby stimulate chaperone-independent functions of HspBP1.

  20. Genome-wide analysis of the potato Hsp20 gene family: identification, genomic organization and expression profiles in response to heat stress.

    Science.gov (United States)

    Zhao, Peng; Wang, Dongdong; Wang, Ruoqiu; Kong, Nana; Zhang, Chao; Yang, Chenghui; Wu, Wentao; Ma, Haoli; Chen, Qin

    2018-01-18

    Heat shock proteins (Hsps) are essential components in plant tolerance mechanism under various abiotic stresses. Hsp20 is the major family of heat shock proteins, but little of Hsp20 family is known in potato (Solanum tuberosum), which is an important vegetable crop that is thermosensitive. To reveal the mechanisms of potato Hsp20s coping with abiotic stresses, analyses of the potato Hsp20 gene family were conducted using bioinformatics-based methods. In total, 48 putative potato Hsp20 genes (StHsp20s) were identified and named according to their chromosomal locations. A sequence analysis revealed that most StHsp20 genes (89.6%) possessed no, or only one, intron. A phylogenetic analysis indicated that all of the StHsp20 genes, except 10, were grouped into 12 subfamilies. The 48 StHsp20 genes were randomly distributed on 12 chromosomes. Nineteen tandem duplicated StHsp20s and one pair of segmental duplicated genes (StHsp20-15 and StHsp20-48) were identified. A cis-element analysis inferred that StHsp20s, except for StHsp20-41, possessed at least one stress response cis-element. A heatmap of the StHsp20 gene family showed that the genes, except for StHsp20-2 and StHsp20-45, were expressed in various tissues and organs. Real-time quantitative PCR was used to detect the expression level of StHsp20 genes and demonstrated that the genes responded to multiple abiotic stresses, such as heat, salt or drought stress. The relative expression levels of 14 StHsp20 genes (StHsp20-4, 6, 7, 9, 20, 21, 33, 34, 35, 37, 41, 43, 44 and 46) were significantly up-regulated (more than 100-fold) under heat stress. These results provide valuable information for clarifying the evolutionary relationship of the StHsp20 family and in aiding functional characterization of StHsp20 genes in further research.

  1. Hsp90 inhibitors reduce influenza virus replication in cell culture

    International Nuclear Information System (INIS)

    Chase, Geoffrey; Deng, Tao; Fodor, Ervin; Leung, B.W.; Mayer, Daniel; Schwemmle, Martin; Brownlee, George

    2008-01-01

    The viral RNA polymerase complex of influenza A virus consists of three subunits PB1, PB2 and PA. Recently, the cellular chaperone Hsp90 was shown to play a role in nuclear import and assembly of the trimeric polymerase complex by binding to PB1 and PB2. Here we show that Hsp90 inhibitors, geldanamycin or its derivative 17-AAG, delay the growth of influenza virus in cell culture resulting in a 1-2 log reduction in viral titre early in infection. We suggest that this is caused by the reduced half-life of PB1 and PB2 and inhibition of nuclear import of PB1 and PA which lead to reduction in viral RNP assembly. Hsp90 inhibitors may represent a new class of antiviral compounds against influenza viruses

  2. Robust immunoreactivity of teenager sera against peptide 19 from Porphyromonas gingivalis HSP60

    OpenAIRE

    Kwon, Eun-Young; Cha, Gil Sun; Joo, Ji-Young; Lee, Ju-Youn; Choi, Jeomil

    2017-01-01

    Purpose Epitope spreading is a phenomenon in which distinct subdominant epitopes become major targets of the immune response. Heat shock protein (HSP) 60 from Porphyromonas gingivalis (PgHSP60) and peptide 19 from PgHSP60 (Pep19) are immunodominant epitopes in autoimmune disease patients, including those with periodontitis. It remains unclear whether Pep19 is a dominant epitope in subjects without periodontitis or autoimmune disease. The purpose of this study was to determine the epitope spre...

  3. Heat shock protein Hsp90-2 expression in the Arabidopsis thaliana seedlings under clinorotation

    Science.gov (United States)

    Kozeko, Liudmyla

    Heat shock proteins 90 kDa (Hsp90) are abundant under normal conditions and induced by stress. This family is distinguished from other chaperones in that most of its substrates are signal transduction proteins. Previously, we determined some time-dependent increase in the Hsp90 level in pea seedlings in response to simulated microgravity that indicated a stress-reaction. However, expression of the individual members of the Hsp90 family have specific pattern. The purpose of this study was to investigate possible alterations in the gene expression pattern of cytosolic Hsp90-2 in Arabidopsis thaliana seedlings under 2D-clinorotation. To obtain detailed expression pattern of the HSP90-2 genes we used seeds that provides a resource of loss-of-function mutations gene expression patterns via translational fusions with the reporter gene, GUS (a line N 166718, NASC). There were two variants of the experiment: 1) seedlings grew under clinorotation for 10, 12, 14 d; 2) seedlings grew in the stationary conditions for 10 d followed by clinorotation for 3 h -at 22o C and 16h light cycle. The seedlings grown in the stationary conditions were used as a control. GUS staining showed that HSP90-2 expression was regulated during seedling development and affected by clinorotation in the heterozygous mutant plants. In the homozygous for the mutation plants, HSP90-2 expression was stable during seedling development and not affected by clinorotation. GUS staining was observed in cotyledons, leaves and hypocotyls of the seedlings (especially intense in vascular bundles), indicating intensive cellular processes with participation of this chaperone. Possible pathways of influence of clinorotation on HSP90-2 expression are discussed.

  4. Involvement of yeast HSP90 isoforms in response to stress and cell death induced by acetic acid.

    Directory of Open Access Journals (Sweden)

    Alexandra Silva

    Full Text Available Acetic acid-induced apoptosis in yeast is accompanied by an impairment of the general protein synthesis machinery, yet paradoxically also by the up-regulation of the two isoforms of the heat shock protein 90 (HSP90 chaperone family, Hsc82p and Hsp82p. Herein, we show that impairment of cap-dependent translation initiation induced by acetic acid is caused by the phosphorylation and inactivation of eIF2α by Gcn2p kinase. A microarray analysis of polysome-associated mRNAs engaged in translation in acetic acid challenged cells further revealed that HSP90 mRNAs are over-represented in this polysome fraction suggesting preferential translation of HSP90 upon acetic acid treatment. The relevance of HSP90 isoform translation during programmed cell death (PCD was unveiled using genetic and pharmacological abrogation of HSP90, which suggests opposing roles for HSP90 isoforms in cell survival and death. Hsc82p appears to promote survival and its deletion leads to necrotic cell death, while Hsp82p is a pro-death molecule involved in acetic acid-induced apoptosis. Therefore, HSP90 isoforms have distinct roles in the control of cell fate during PCD and their selective translation regulates cellular response to acetic acid stress.

  5. The conformational dynamics of the mitochondrial Hsp70 chaperone.

    Science.gov (United States)

    Mapa, Koyeli; Sikor, Martin; Kudryavtsev, Volodymyr; Waegemann, Karin; Kalinin, Stanislav; Seidel, Claus A M; Neupert, Walter; Lamb, Don C; Mokranjac, Dejana

    2010-04-09

    Heat shock proteins 70 (Hsp70) represent a ubiquitous and conserved family of molecular chaperones involved in a plethora of cellular processes. The dynamics of their ATP hydrolysis-driven and cochaperone-regulated conformational cycle are poorly understood. We used fluorescence spectroscopy to analyze, in real time and at single-molecule resolution, the effects of nucleotides and cochaperones on the conformation of Ssc1, a mitochondrial member of the family. We report that the conformation of its ADP state is unexpectedly heterogeneous, in contrast to a uniform ATP state. Substrates are actively involved in determining the conformation of Ssc1. The J protein Mdj1 does not interact transiently with the chaperone, as generally believed, but rather is released slowly upon ATP hydrolysis. Analysis of the major bacterial Hsp70 revealed important differences between highly homologous members of the family, possibly explaining tuning of Hsp70 chaperones to meet specific functions in different organisms and cellular compartments. 2010 Elsevier Inc. All rights reserved.

  6. Vitamin A-coupled liposomes containing siRNA against HSP47 ameliorate skin fibrosis in chronic graft-versus-host disease.

    Science.gov (United States)

    Yamakawa, Tomohiro; Ohigashi, Hiroyuki; Hashimoto, Daigo; Hayase, Eiko; Takahashi, Shuichiro; Miyazaki, Miyono; Minomi, Kenjiro; Onozawa, Masahiro; Niitsu, Yoshiro; Teshima, Takanori

    2018-03-29

    Chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (SCT) is characterized by multiorgan fibrosis and profoundly affects the quality of life of transplant survivors. Heat shock protein 47 (HSP47), a collagen-specific molecular chaperone, plays a critical role in collagen synthesis in myofibroblasts. We explored the role of HSP47 in the fibrotic process of cutaneous chronic GVHD in mice. Immunohistochemical analysis showed massive fibrosis with elevated amounts of collagen deposits and accumulation of F4/80 + macrophages, as well as myofibroblasts expressing HSP47 and retinol-binding protein 1 in the skin after allogeneic SCT. Repeated injection of anti-colony-stimulating factor (CSF-1) receptor-blocking antibodies significantly reduced HSP47 + myofibroblasts in the skin, indicating a macrophage-dependent accumulation of myofibroblasts. Vitamin A-coupled liposomes carrying HSP47 small interfering RNA (siRNA) (VA-lip HSP47) delivered HSP47 siRNA to cells expressing vitamin A receptors and knocked down their HSP47 in vitro. Intravenously injected VA-lip HSP47 were specifically distributed to skin fibrotic lesions and did not affect collagen synthesis in healthy skin. VA-lip HSP47 knocked down HSP47 expression in myofibroblasts and significantly reduced collagen deposition without inducing systemic immunosuppression. It also abrogated fibrosis in the salivary glands. These results highlight a cascade of fibrosis in chronic GVHD; macrophage production of transforming growth factor β mediates fibroblast differentiation to HSP47 + myofibroblasts that produce collagen. VA-lip HSP47 represent a novel strategy to modulate fibrosis in chronic GVHD by targeting HSP47 + myofibroblasts without inducing immunosuppression. © 2018 by The American Society of Hematology.

  7. Engineering BioBrick vectors from BioBrick parts

    Directory of Open Access Journals (Sweden)

    Knight Thomas F

    2008-04-01

    Full Text Available Abstract Background The underlying goal of synthetic biology is to make the process of engineering biological systems easier. Recent work has focused on defining and developing standard biological parts. The technical standard that has gained the most traction in the synthetic biology community is the BioBrick standard for physical composition of genetic parts. Parts that conform to the BioBrick assembly standard are BioBrick standard biological parts. To date, over 2,000 BioBrick parts have been contributed to, and are available from, the Registry of Standard Biological Parts. Results Here we extended the same advantages of BioBrick standard biological parts to the plasmid-based vectors that are used to provide and propagate BioBrick parts. We developed a process for engineering BioBrick vectors from BioBrick parts. We designed a new set of BioBrick parts that encode many useful vector functions. We combined the new parts to make a BioBrick base vector that facilitates BioBrick vector construction. We demonstrated the utility of the process by constructing seven new BioBrick vectors. We also successfully used the resulting vectors to assemble and propagate other BioBrick standard biological parts. Conclusion We extended the principles of part reuse and standardization to BioBrick vectors. As a result, myriad new BioBrick vectors can be readily produced from all existing and newly designed BioBrick parts. We invite the synthetic biology community to (1 use the process to make and share new BioBrick vectors; (2 expand the current collection of BioBrick vector parts; and (3 characterize and improve the available collection of BioBrick vector parts.

  8. A filter technique for optimising the photon energy response of a silicon pin diode dosemeter

    International Nuclear Information System (INIS)

    Olsher, R.H.; Eisen, Y.

    1996-01-01

    Unless they are energy compensated, silicon PIN diodes used in electronic pocket dosemeters, have significant over-response below 200 keV. Siemens is using three diodes in parallel with individual filters to produce excellent energy and angular response. An algorithm based on the photon spectrum of a single diode could be used to flatten the energy response. The commercial practice is to use a single diode with a simple filter to flatten the energy response, despite the mediocre low energy photon. The filter technique with an opening has been used for energy compensating GM detectors and proportional counters and a new variation of it has been investigated which compensates the energy response of a silicon PIN diode and maintains an extended low energy response. It uses a composite filter of two or more materials with several openings whose individual area is in the range of 15% to 25% of the diode's active area. One opening is centred over the diode's active area and others are located at the periphery of the active area to preserve a good polar response to ±45 o . Monte Carlo radiation transport methods were used to simulate the coupled electron-photon transport through a Hamamatsu S2506-01 diode and to determine the energy response of the diode for a variety of filters. In current mode, the resultant dosemeter energy response relative to air dose was within -15% and +30% for 0 o incidence over the energy range from 15 keV to 1 MeV. In pulse mode, the resultant dosemeter energy response was within -25% and +50% for 0 o incidence over the energy range from 30 keV to 10 MeV. For ±45 o incidence, the energy response was within -25% and +40% from 40 keV to 10 MeV. Theoretical viability of the filter technique has been shown in this work (Author)

  9. Expression analysis of NOS family and HSP genes during thermal stress in goat ( Capra hircus)

    Science.gov (United States)

    Yadav, Vijay Pratap; Dangi, Satyaveer Singh; Chouhan, Vikrant Singh; Gupta, Mahesh; Dangi, Saroj K.; Singh, Gyanendra; Maurya, Vijay Prakash; Kumar, Puneet; Sarkar, Mihir

    2016-03-01

    Approximately 50 genes other than heat shock protein (HSP) expression changes during thermal stress. These genes like nitric oxide synthase (NOS) need proper attention and investigation to find out their possible role in the adaptation to thermal stress in animals. So, the present study was undertaken to demonstrate the expressions of inducible form type II NOS (iNOS), endothelial type III NOS (eNOS), constitutively expressed enzyme NOS (cNOS), HSP70, and HSP90 in peripheral blood mononuclear cells (PBMCs) during different seasons in Barbari goats. Real-time polymerase chain reaction, western blot, and immunocytochemistry were applied to investigate messenger RNA (mRNA) expression, protein expression, and immunolocalization of examined factors. The mRNA and protein expressions of iNOS, eNOS, cNOS, HSP70, and HSP90 were significantly higher ( P goats.

  10. Molecular analysis of Hsp70 mechanisms in plants and their function in response to stress.

    Science.gov (United States)

    Usman, Magaji G; Rafii, Mohd Y; Martini, Mohammad Y; Yusuff, Oladosu A; Ismail, Mohd R; Miah, Gous

    2017-04-01

    Studying the strategies of improving abiotic stress tolerance is quite imperative and research under this field will increase our understanding of response mechanisms to abiotic stress such as heat. The Hsp70 is an essential regulator of protein having the tendency to maintain internal cell stability like proper folding protein and breakdown of unfolded proteins. Hsp70 holds together protein substrates to help in movement, regulation, and prevent aggregation under physical and or chemical pressure. However, this review reports the molecular mechanism of heat shock protein 70 kDa (Hsp70) action and its structural and functional analysis, research progress on the interaction of Hsp70 with other proteins and their interaction mechanisms as well as the involvement of Hsp70 in abiotic stress responses as an adaptive defense mechanism.

  11. An Impermeant Ganetespib Analog Inhibits Extracellular Hsp90-Mediated Cancer Cell Migration that Involves Lysyl Oxidase 2-like Protein

    Energy Technology Data Exchange (ETDEWEB)

    McCready, Jessica [Department of Natural Sciences, Assumption College, Worcester, MA 01609 (United States); Wong, Daniel S. [Department of Developmental Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111 (United States); Cell and Molecular Physiology Program, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111 (United States); Burlison, Joseph A.; Ying, Weiwen [Synta Pharmaceuticals, Lexington, MA 02421 (United States); Jay, Daniel G., E-mail: daniel.jay@tufts.edu [Department of Developmental Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111 (United States); Cell and Molecular Physiology Program, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111 (United States)

    2014-04-30

    Extracellular Hsp90 (eHsp90) activates a number of client proteins outside of cancer cells required for migration and invasion. Therefore, eHsp90 may serve as a novel target for anti-metastatic drugs as its inhibition using impermeant Hsp90 inhibitors would not affect the numerous vital intracellular Hsp90 functions in normal cells. While some eHsp90 clients are known, it is important to establish other proteins that act outside the cell to validate eHsp90 as a drug target to limit cancer spread. Using mass spectrometry we identified two precursor proteins Galectin 3 binding protein (G3BP) and Lysyl oxidase 2-like protein (LOXL2) that associate with eHsp90 in MDA-MB231 breast cancer cell conditioned media and confirmed that LOXL2 binds to eHsp90 in immunoprecipitates. We introduce a novel impermeant Hsp90 inhibitor STA-12-7191 derived from ganetespib and show that it is markedly less toxic to cells and can inhibit cancer cell migration in a dose dependent manner. We used STA-12-7191 to test if LOXL2 and G3BP are potential eHsp90 clients. We showed that while LOXL2 can increase wound healing and compensate for STA-12-7191-mediated inhibition of wound closure, addition of G3BP had no affect on this assay. These findings support of role for LOXL2 in eHsp90 stimulated cancer cell migration and provide preliminary evidence for the use of STA-12-7191 to inhibit eHsp90 to limit cancer invasion.

  12. An Impermeant Ganetespib Analog Inhibits Extracellular Hsp90-Mediated Cancer Cell Migration that Involves Lysyl Oxidase 2-like Protein

    International Nuclear Information System (INIS)

    McCready, Jessica; Wong, Daniel S.; Burlison, Joseph A.; Ying, Weiwen; Jay, Daniel G.

    2014-01-01

    Extracellular Hsp90 (eHsp90) activates a number of client proteins outside of cancer cells required for migration and invasion. Therefore, eHsp90 may serve as a novel target for anti-metastatic drugs as its inhibition using impermeant Hsp90 inhibitors would not affect the numerous vital intracellular Hsp90 functions in normal cells. While some eHsp90 clients are known, it is important to establish other proteins that act outside the cell to validate eHsp90 as a drug target to limit cancer spread. Using mass spectrometry we identified two precursor proteins Galectin 3 binding protein (G3BP) and Lysyl oxidase 2-like protein (LOXL2) that associate with eHsp90 in MDA-MB231 breast cancer cell conditioned media and confirmed that LOXL2 binds to eHsp90 in immunoprecipitates. We introduce a novel impermeant Hsp90 inhibitor STA-12-7191 derived from ganetespib and show that it is markedly less toxic to cells and can inhibit cancer cell migration in a dose dependent manner. We used STA-12-7191 to test if LOXL2 and G3BP are potential eHsp90 clients. We showed that while LOXL2 can increase wound healing and compensate for STA-12-7191-mediated inhibition of wound closure, addition of G3BP had no affect on this assay. These findings support of role for LOXL2 in eHsp90 stimulated cancer cell migration and provide preliminary evidence for the use of STA-12-7191 to inhibit eHsp90 to limit cancer invasion

  13. Characterisation of a Personal TL Photon Dosemeter Based on Two LiF(Mg,Cu,P) Detectors in Terms of Hp(0.07,alpha) and Hp(10,alpha)

    International Nuclear Information System (INIS)

    Fantuzzi, E.; Monteventi, F.; Sermenghi, I.; Uleri, G.

    1999-01-01

    A study was undertaken to evaluate the response of the ENEA Photon Personal Dosemeter, slightly modified in design, in terms of H p (0.07, α) and H p (10, α). A filtration of 20 and 270 mg.cm -2 respectively for the two LiF(Mg,Cu,P) detectors employed was adopted according to a preliminary analytical simulation. The new dosemeter can measure both H p (0.07, α) with a maximum uncertainty of ±4% in the range from 10 to 200 keV and H p (10, α) with a maximum uncertainty of ±15% in the range from 10 keV to 1.25 MeV, using the detector responses together with a correction function with respect to their ratio. Moreover, tests were performed to evaluate the dosemeter angular response (0 deg., 20 deg., 40 deg., and 60 deg.) obtaining good results according to international recommendations. All irradiation tests were performed at SSL of ENEA Institute for Radiation Protection in Bologna using the ISO water phantom (30 x 30 x 15 cm 3 ) and standard ISO filtered X ray beams as well as 137 Cs and 60 Co sources. This work represents a preliminary type test of the ENEA photon personal dosemeter and allows its introduction in routine dosimetry practice in accordance with the ICRU reference quantities. (author)

  14. HSP70 expression in the copper butterfly Lycaena tityrus across altitudes and temperatures

    DEFF Research Database (Denmark)

    Karl, I.; Sørensen, Jesper Givskov; Loeschcke, Volker

    2009-01-01

    temperatures show differences in HSP70 expression. HSP70 expression increased substantially at the higher rearing temperature in low-altitude butterflies, which might represent an adaptation to occasionally occurring heat spells. On the other hand, high-altitude butterflies showed much less plasticity...... in response to rearing temperatures, and overall seem to rely more on genetically fixed thermal stress resistance. Whether the latter indicates a higher vulnerability of high-altitude populations to global warming needs further investigation. HSP70 expression increased with both colder and warmer induction......The ability to express heat-shock proteins (HSP) under thermal stress is an essential mechanism for ectotherms to cope with unfavourable conditions. In this study, we investigate if Copper butterflies originating from different altitudes and/or being exposed to different rearing and induction...

  15. Little effect of HSP90 inhibition on the quantitative wing traits variation in Drosophila melanogaster.

    Science.gov (United States)

    Takahashi, Kazuo H

    2017-02-01

    Drosophila wings have been a model system to study the effect of HSP90 on quantitative trait variation. The effect of HSP90 inhibition on environmental buffering of wing morphology varies among studies while the genetic buffering effect of it was examined in only one study and was not detected. Variable results so far might show that the genetic background influences the environmental and genetic buffering effect of HSP90. In the previous studies, the number of the genetic backgrounds used is limited. To examine the effect of HSP90 inhibition with a larger number of genetic backgrounds than the previous studies, 20 wild-type strains of Drosophila melanogaster were used in this study. Here I investigated the effect of HSP90 inhibition on the environmental buffering of wing shape and size by assessing within-individual and among-individual variations, and as a result, I found little or very weak effects on environmental and genetic buffering. The current results suggest that the role of HSP90 as a global regulator of environmental and genetic buffering is limited at least in quantitative traits.

  16. Hsp104 suppresses polyglutamine-induced degeneration post onset in a drosophila MJD/SCA3 model.

    Directory of Open Access Journals (Sweden)

    Mimi Cushman-Nick

    Full Text Available There are no effective therapeutics that antagonize or reverse the protein-misfolding events underpinning polyglutamine (PolyQ disorders, including Spinocerebellar Ataxia Type-3 (SCA3. Here, we augment the proteostasis network of Drosophila SCA3 models with Hsp104, a powerful protein disaggregase from yeast, which is bafflingly absent from metazoa. Hsp104 suppressed eye degeneration caused by a C-terminal ataxin-3 (MJD fragment containing the pathogenic expanded PolyQ tract, but unexpectedly enhanced aggregation and toxicity of full-length pathogenic MJD. Hsp104 suppressed toxicity of MJD variants lacking a portion of the N-terminal deubiquitylase domain and full-length MJD variants unable to engage polyubiquitin, indicating that MJD-ubiquitin interactions hinder protective Hsp104 modalities. Importantly, in staging experiments, Hsp104 suppressed toxicity of a C-terminal MJD fragment when expressed after the onset of PolyQ-induced degeneration, whereas Hsp70 was ineffective. Thus, we establish the first disaggregase or chaperone treatment administered after the onset of pathogenic protein-induced degeneration that mitigates disease progression.

  17. HSP60, a protein downregulated by IGFBP7 in colorectal carcinoma

    Directory of Open Access Journals (Sweden)

    Lin Jie

    2010-04-01

    Full Text Available Abstract Background In our previous study, it was well defined that IGFBP7 was an important tumor suppressor gene in colorectal cancer (CRC. We aimed to uncover the downstream molecules responsible for IGFBP7's behaviour in this study. Methods Differentially expressed protein profiles between PcDNA3.1(IGFBP7-transfected RKO cells and the empty vector transfected controls were generated by two-dimensional gel electrophoresis (2-DE and mass spectrometry (MS identification. The selected differentially expressed protein induced by IGFBP7 was confirmed by western blot and ELISA. The biological behaviour of the protein was explored by cell growth assay and colony formation assay. Results Six unique proteins were found differentially expressed in PcDNA3.1(IGFBP7-transfected RKO cells, including albumin (ALB, 60 kDa heat shock protein(HSP60, Actin cytoplasmic 1 or 2, pyruvate kinase muscle 2(PKM2, beta subunit of phenylalanyl-tRNA synthetase(FARSB and hypothetical protein. The downregulation of HSP60 by IGFBP7 was confirmed by western blot and ELISA. Recombinant human HSP60 protein could increase the proliferation rate and the colony formation ability of PcDNA3.1(IGFBP7-RKO cells. Conclusion HSP60 was an important downstream molecule of IGFBP7. The downregulation of HSP60 induced by IGFBP7 may be, at least in part, responsible for IGFBP7's tumor suppressive biological behaviour in CRC.

  18. Cyclophilin 40 facilitates HSP90-mediated RISC assembly in plants.

    Science.gov (United States)

    Iki, Taichiro; Yoshikawa, Manabu; Meshi, Tetsuo; Ishikawa, Masayuki

    2012-01-18

    Posttranscriptional gene silencing is mediated by RNA-induced silencing complexes (RISCs) that contain AGO proteins and single-stranded small RNAs. The assembly of plant AGO1-containing RISCs depends on the molecular chaperone HSP90. Here, we demonstrate that cyclophilin 40 (CYP40), protein phosphatase 5 (PP5), and several other proteins with the tetratricopeptide repeat (TPR) domain associates with AGO1 in an HSP90-dependent manner in extracts of evacuolated tobacco protoplasts (BYL). Intriguingly, CYP40, but not the other TPR proteins, could form a complex with small RNA duplex-bound AGO1. Moreover, CYP40 that was synthesized by in-vitro translation using BYL uniquely facilitated binding of small RNA duplexes to AGO1, and as a result, increased the amount of mature RISCs that could cleave target RNAs. CYP40 was not contained in mature RISCs, indicating that the association is transient. Addition of PP5 or cyclophilin-binding drug cyclosporine A prevented the association of endogenous CYP40 with HSP90-AGO1 complex and inhibited RISC assembly. These results suggest that a complex of AGO1, HSP90, CYP40, and a small RNA duplex is a key intermediate of RISC assembly in plants.

  19. Crosstalk between p38, Hsp25 and Akt in spinal motor neurons after sciatic nerve injury

    Science.gov (United States)

    Murashov, A. K.; Ul Haq, I.; Hill, C.; Park, E.; Smith, M.; Wang, X.; Wang, X.; Goldberg, D. J.; Wolgemuth, D. J.

    2001-01-01

    The p38 stress-activated protein kinase pathway is involved in regulation of phosphorylation of Hsp25, which in turn regulates actin filament dynamic in non-neuronal cells. We report that p38, Hsp25 and Akt signaling pathways were specifically activated in spinal motor neurons after sciatic nerve axotomy. The activation of the p38 kinase was required for induction of Hsp25 expression. Furthermore, Hsp25 formed a complex with Akt, a member of PI-3 kinase pathway that prevents neuronal cell death. Together, our observations implicate Hsp25 as a central player in a complex system of signaling that may both promote regeneration of nerve fibers and prevent neuronal cell death in the injured spinal cord.

  20. Mitochondrial-type hsp70 genes of the amitochondriate protists, Giardia intestinalis, Entamoeba histolytica and two microsporidians☆

    Science.gov (United States)

    Arisue, Nobuko; Sánchez, Lidya B.; Weiss, Louis M.; Müller, Miklós; Hashimoto, Tetsuo

    2011-01-01

    Genes encoding putative mitochondrial-type heat shock protein 70 (mit-hsp70) were isolated and sequenced from amitochondriate protists, Giardia intestinalis, Entamoeba histolytica, and two microsporidians, Encephalitozoon hellem and Glugea plecoglossi. The deduced mit-hsp70 sequences were analyzed by sequence alignments and phylogenetic reconstructions. The mit-hsp70 sequence of these four amitochondriate protists were divergent from other mit-hsp70 sequences of mitochondriate eukaryotes. However, all of these sequences were clearly located within a eukaryotic mitochondrial clade in the tree including various type hsp70 sequences, supporting the emerging notion that none of these amitochondriate lineages are primitively amitochodrial, but lost their mitochondria secondarily in their evolutionary past. PMID:11880223

  1. The regulatory mechanism of Hsp90α secretion from endothelial cells and its role in angiogenesis during wound healing

    International Nuclear Information System (INIS)

    Song, Xiaomin; Luo, Yongzhang

    2010-01-01

    Research highlights: → Growth factors such as bFGF, VEGF, PDGF and SDF-1 stimulate Hsp90α secretion from endothelial cells. → Secreted Hsp90α localizes on the leading edge of activated endothelial cells. → Secreted Hsp90α promotes angiogenesis in wound healing. -- Abstract: Heat shock protein 90α (Hsp90α) is a ubiquitously expressed molecular chaperone, which is essential for the maintenance of eukaryote homeostasis. Hsp90α can also be secreted extracellularly and is associated with several physiological and pathological processes including wound healing, cancer, infectious diseases and diabetes. Angiogenesis, defined as the sprouting of new blood vessels from pre-existing capillaries via endothelial cell proliferation and migration, commonly occurs in and contributes to the above mentioned processes. However, the secretion of Hsp90α from endothelial cells and also its function in angiogenesis are still unclear. Here we investigated the role of extracellular Hsp90α in angiogenesis using dermal endothelial cells in vitro and a wound healing model in vivo. We find that the secretion of Hsp90α but not Hsp90β is increased in activated endothelial cells with the induction of angiogenic factors and matrix proteins. Secreted Hsp90α localizes on the leading edge of endothelial cells and promotes their angiogenic activities, whereas Hsp90α neutralizing antibodies reverse the effect. Furthermore, using a mouse skin wound healing model in vivo, we demonstrate that extracellular Hsp90α localizes on blood vessels in granulation tissues of wounded skin and promotes angiogenesis during wound healing. Taken together, our study reveals that Hsp90α can be secreted by activated endothelial cells and is a positive regulator of angiogenesis, suggesting the potential application of Hsp90α as a stimulator for wound repair.

  2. The regulatory mechanism of Hsp90{alpha} secretion from endothelial cells and its role in angiogenesis during wound healing

    Energy Technology Data Exchange (ETDEWEB)

    Song, Xiaomin [National Engineering Laboratory for Anti-tumor Protein Therapeutics, Tsinghua University, Beijing 100084 (China); Beijing Key Laboratory for Protein Therapeutics, Tsinghua University, Beijing 100084 (China); Cancer Biology Laboratory, School of Life Sciences, Tsinghua University, Beijing 100084 (China); Luo, Yongzhang, E-mail: yluo@tsinghua.edu.cn [National Engineering Laboratory for Anti-tumor Protein Therapeutics, Tsinghua University, Beijing 100084 (China); Beijing Key Laboratory for Protein Therapeutics, Tsinghua University, Beijing 100084 (China); Cancer Biology Laboratory, School of Life Sciences, Tsinghua University, Beijing 100084 (China)

    2010-07-16

    Research highlights: {yields} Growth factors such as bFGF, VEGF, PDGF and SDF-1 stimulate Hsp90{alpha} secretion from endothelial cells. {yields} Secreted Hsp90{alpha} localizes on the leading edge of activated endothelial cells. {yields} Secreted Hsp90{alpha} promotes angiogenesis in wound healing. -- Abstract: Heat shock protein 90{alpha} (Hsp90{alpha}) is a ubiquitously expressed molecular chaperone, which is essential for the maintenance of eukaryote homeostasis. Hsp90{alpha} can also be secreted extracellularly and is associated with several physiological and pathological processes including wound healing, cancer, infectious diseases and diabetes. Angiogenesis, defined as the sprouting of new blood vessels from pre-existing capillaries via endothelial cell proliferation and migration, commonly occurs in and contributes to the above mentioned processes. However, the secretion of Hsp90{alpha} from endothelial cells and also its function in angiogenesis are still unclear. Here we investigated the role of extracellular Hsp90{alpha} in angiogenesis using dermal endothelial cells in vitro and a wound healing model in vivo. We find that the secretion of Hsp90{alpha} but not Hsp90{beta} is increased in activated endothelial cells with the induction of angiogenic factors and matrix proteins. Secreted Hsp90{alpha} localizes on the leading edge of endothelial cells and promotes their angiogenic activities, whereas Hsp90{alpha} neutralizing antibodies reverse the effect. Furthermore, using a mouse skin wound healing model in vivo, we demonstrate that extracellular Hsp90{alpha} localizes on blood vessels in granulation tissues of wounded skin and promotes angiogenesis during wound healing. Taken together, our study reveals that Hsp90{alpha} can be secreted by activated endothelial cells and is a positive regulator of angiogenesis, suggesting the potential application of Hsp90{alpha} as a stimulator for wound repair.

  3. Hsp60 and p70S6K form a complex in human cardiomyocytes

    Directory of Open Access Journals (Sweden)

    Kroupskaya I. V.

    2011-02-01

    Full Text Available Molecular chaperon Hsp60 and protein kinase p70S6K play an important functional role in the regulation of cardiomyocytes vital function or apoptosis. Aim. To study a possibility of in vivo complex formation between Hsp60 and p70S6K in cardiomyocytes. Methods. Co-immunoprecipitation, Western-blot analysis. Results. We have identified in vivo interaction between molecular chaperone Hsp60 and two isoforms of proteinkinase p70S6K in human myocardium, normal and affected by cardiomyopathy. Conclusions. The results obtained suggest a possible participation of molecular chaperon Hsp60 in regulation of p70S6K activity in stressinduced apoptotic signaling pathway in cardiomyocytes.

  4. Overexpression of a heat shock protein (ThHSP18.3) from Tamarix hispida confers stress tolerance to yeast.

    Science.gov (United States)

    Gao, Caiqiu; Jiang, Bo; Wang, Yucheng; Liu, Guifeng; Yang, Chuanping

    2012-04-01

    It is well known that plant heat shock proteins (HSPs) play important roles both in response to adverse environmental conditions and in various developmental processes. However, among plant HSPs, the functions of tree plant HSPs are poorly characterized. To improve our understanding of tree HSPs, we cloned and characterized an HSP gene (ThHSP18.3) from Tamarix hispida. Sequence alignment reveals that ThHSP18.3 belongs to the class I small heat shock protein family. A transient expression assay showed that ThHSP18.3 protein was targeted to the cell nucleus. Treatment of Tamarix hispida with cold and heat shock highly induced ThHSP18.3 expression in all studied leaves, roots and stems, whereas, treatment of T. hispida with NaCl, NaHCO(3), and PEG induced ThHSP18.3 expression in leaves and decreased its expression in roots and stems. Further, to study the role of ThHSP18.3 in stress tolerance under different stress conditions, we cloned ThHSP18.3 into the pYES2 vector, transformed and expressed the vector in yeast Saccharomyces cerevisiae. Yeast cells transformed with an empty pYES2 vector were employed as a control. Compared to the control, yeast cells expressing ThHSP18.3 showed greater tolerance to salt, drought, heavy metals, and both low and high temperatures, indicating that ThHSP18.3 confers tolerance to these stress conditions. These results suggested that ThHSP18.3 is involved in tolerance to a variety of stress conditions in T. hispida.

  5. A Hyperactive Signalosome in Acute Myeloid Leukemia Drives Addiction to a Tumor-Specific Hsp90 Species

    Directory of Open Access Journals (Sweden)

    Hongliang Zong

    2015-12-01

    Full Text Available Acute myeloid leukemia (AML is a heterogeneous and fatal disease with an urgent need for improved therapeutic regimens given that most patients die from relapsed disease. Irrespective of mutation status, the development of aggressive leukemias is enabled by increasing dependence on signaling networks. We demonstrate that a hyperactive signalosome drives addiction of AML cells to a tumor-specific Hsp90 species (teHsp90. Through genetic, environmental, and pharmacologic perturbations, we demonstrate a direct and quantitative link between hyperactivated signaling pathways and apoptotic sensitivity of AML to teHsp90 inhibition. Specifically, we find that hyperactive JAK-STAT and PI3K-AKT signaling networks are maintained by teHsp90 and, in fact, gradual activation of these networks drives tumors increasingly dependent on teHsp90. Thus, although clinically aggressive AML survives via signalosome activation, this addiction creates a vulnerability that can be exploited with Hsp90-directed therapy.

  6. The expression of HSP in human skeletal muscle. Effects of muscle fiber phenotype and training background

    DEFF Research Database (Denmark)

    Folkesson, Mattias; Mackey, Abigail L; Langberg, Henning

    2013-01-01

    AIM: Exercise-induced adaptations of skeletal muscle are related to training mode and can be muscle fibre type specific. This study aimed to investigate heat shock protein expression in type I and type II muscle fibres in resting skeletal muscle of subjects with different training backgrounds...... myosin heavy chain I and IIA, αB-crystallin, HSP27, HSP60 and HSP70. RESULTS: In ACT and RES, but not in END, a fibre type specific expression with higher staining intensity in type I than type II fibres was seen for αB-crystallin. The opposite (II>I) was found for HSP27 in subjects from ACT (6 of 12...... HSPs in human skeletal muscle is influenced by muscle fibre phenotype. The fibre type specific expression of HSP70 is influenced by resistance and endurance training whereas those of αB-crystallin and HSP27 are influenced only by endurance training suggesting the existence of a training...

  7. BAG3 Is a Modular, Scaffolding Protein that physically Links Heat Shock Protein 70 (Hsp70) to the Small Heat Shock Proteins.

    Science.gov (United States)

    Rauch, Jennifer N; Tse, Eric; Freilich, Rebecca; Mok, Sue-Ann; Makley, Leah N; Southworth, Daniel R; Gestwicki, Jason E

    2017-01-06

    Small heat shock proteins (sHsps) are a family of ATP-independent molecular chaperones that are important for binding and stabilizing unfolded proteins. In this task, the sHsps have been proposed to coordinate with ATP-dependent chaperones, including heat shock protein 70 (Hsp70). However, it is not yet clear how these two important components of the chaperone network are linked. We report that the Hsp70 co-chaperone, BAG3, is a modular, scaffolding factor to bring together sHsps and Hsp70s. Using domain deletions and point mutations, we found that BAG3 uses both of its IPV motifs to interact with sHsps, including Hsp27 (HspB1), αB-crystallin (HspB5), Hsp22 (HspB8), and Hsp20 (HspB6). BAG3 does not appear to be a passive scaffolding factor; rather, its binding promoted de-oligomerization of Hsp27, likely by competing for the self-interactions that normally stabilize large oligomers. BAG3 bound to Hsp70 at the same time as Hsp22, Hsp27, or αB-crystallin, suggesting that it might physically bring the chaperone families together into a complex. Indeed, addition of BAG3 coordinated the ability of Hsp22 and Hsp70 to refold denatured luciferase in vitro. Together, these results suggest that BAG3 physically and functionally links Hsp70 and sHsps. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Organization and evolution of hsp70 clusters strikingly differ in two species of Stratiomyidae (Diptera inhabiting thermally contrasting environments

    Directory of Open Access Journals (Sweden)

    Bettencourt Brian R

    2011-03-01

    Full Text Available Abstract Background Previously, we described the heat shock response in dipteran species belonging to the family Stratiomyidae that develop in thermally and chemically contrasting habitats including highly aggressive ones. Although all species studied exhibit high constitutive levels of Hsp70 accompanied by exceptionally high thermotolerance, we also detected characteristic interspecies differences in heat shock protein (Hsp expression and survival after severe heat shock. Here, we analyzed genomic libraries from two Stratiomyidae species from thermally and chemically contrasting habitats and determined the structure and organization of their hsp70 clusters. Results Although the genomes of both species contain similar numbers of hsp70 genes, the spatial distribution of hsp70 copies differs characteristically. In a population of the eurytopic species Stratiomys singularior, which exists in thermally variable and chemically aggressive (hypersaline conditions, the hsp70 copies form a tight cluster with approximately equal intergenic distances. In contrast, in a population of the stenotopic Oxycera pardalina that dwells in a stable cold spring, we did not find hsp70 copies in tandem orientation. In this species, the distance between individual hsp70 copies in the genome is very large, if they are linked at all. In O. pardalina we detected the hsp68 gene located next to a hsp70 copy in tandem orientation. Although the hsp70 coding sequences of S. singularior are highly homogenized via conversion, the structure and general arrangement of the hsp70 clusters are highly polymorphic, including gross aberrations, various deletions in intergenic regions, and insertion of incomplete Mariner transposons in close vicinity to the 3'-UTRs. Conclusions The hsp70 gene families in S. singularior and O. pardalina evolved quite differently from one another. We demonstrated clear evidence of homogenizing gene conversion in the S. singularior hsp70 genes, which form

  9. DNA double strand breaks and Hsp70 expression in proton irradiated living cells

    International Nuclear Information System (INIS)

    Fiedler, Anja; Reinert, Tilo; Tanner, Judith; Butz, Tilman

    2007-01-01

    DNA double strand breaks (DSBs) in living cells can be directly provoked by ionising radiation. DSBs can be visualized by immunostaining the phosphorylated histone γH2AX. Our concern was to test the feasibility of γH2AX staining for a direct visualization of single proton hits. If single protons produce detectable foci, DNA DSBs could be used as 'biological track detectors' for protons. Ionising radiation can also damage proteins indirectly by inducing free radicals. Heat shock proteins (Hsp) help to refold or even degrade the damaged proteins. The level of the most famous heat shock protein Hsp70 is increased by ionising radiation. We investigated the expression of γH2AX and Hsp70 after cross and line patterned irradiation with counted numbers of 2.25 MeV protons on primary human skin fibroblasts. The proton induced DSBs appear more delocalised than it was expected by the ion hit accuracy. Cooling the cells before the irradiation reduces the delocalisation of DNA DSBs, which is probably caused by the reduced diffusion of DNA damaging agents. Proton irradiation seems to provoke protein damages mainly in the cytoplasm indicated by cytoplasmic Hsp70 aggregates. On the contrary, in control heat shocked cells the Hsp70 was predominantly localized in the cell nucleus. However, the irradiated area could not be recognized, all cells on the Si 3 N 4 window showed a homogenous Hsp70 expression pattern

  10. DNA double strand breaks and Hsp70 expression in proton irradiated living cells

    Energy Technology Data Exchange (ETDEWEB)

    Fiedler, Anja [Institute for Experimental Physics II, University of Leipzig (Germany) and Faculty of Biology, Pharmacy and Psychology, University of Leipzig (Germany)]. E-mail: afiedler@uni-leipzig.de; Reinert, Tilo [Institute for Experimental Physics II, University of Leipzig (Germany); Tanner, Judith [Clinic and Polyclinic for Radiation Oncology, University of Halle-Wittenberg (Germany); Butz, Tilman [Institute for Experimental Physics II, University of Leipzig (Germany)

    2007-07-15

    DNA double strand breaks (DSBs) in living cells can be directly provoked by ionising radiation. DSBs can be visualized by immunostaining the phosphorylated histone {gamma}H2AX. Our concern was to test the feasibility of {gamma}H2AX staining for a direct visualization of single proton hits. If single protons produce detectable foci, DNA DSBs could be used as 'biological track detectors' for protons. Ionising radiation can also damage proteins indirectly by inducing free radicals. Heat shock proteins (Hsp) help to refold or even degrade the damaged proteins. The level of the most famous heat shock protein Hsp70 is increased by ionising radiation. We investigated the expression of {gamma}H2AX and Hsp70 after cross and line patterned irradiation with counted numbers of 2.25 MeV protons on primary human skin fibroblasts. The proton induced DSBs appear more delocalised than it was expected by the ion hit accuracy. Cooling the cells before the irradiation reduces the delocalisation of DNA DSBs, which is probably caused by the reduced diffusion of DNA damaging agents. Proton irradiation seems to provoke protein damages mainly in the cytoplasm indicated by cytoplasmic Hsp70 aggregates. On the contrary, in control heat shocked cells the Hsp70 was predominantly localized in the cell nucleus. However, the irradiated area could not be recognized, all cells on the Si{sub 3}N{sub 4} window showed a homogenous Hsp70 expression pattern.

  11. Viability of the Fricke dosemeter doped with methylene blue; Viabilidade do dosimetro Fricke dopado com azul de metileno

    Energy Technology Data Exchange (ETDEWEB)

    Souza, V.L.B.; Santos, C.D.A.; Rodrigues, K.R.G.; Cunha, M.S.; Figueiredo, M.D.C.; Melo, R.T. [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2009-07-01

    This work aims to find the possible utilization of the Fricke dosemeter doped with methylene blue (FMB) for the dosimetry of photodynamic therapy. The FMB was irradiated wit X rays and light emitted diodes demonstrating positive answers to the stimulus, being probably to be used for dosimetric objectives

  12. Cytosine deletion at AP2-box region of HSP70 promoter and its ...

    Indian Academy of Sciences (India)

    of thermotolerance in cells (Leung et al. 1996). ... region of HSP70 significantly affected cellular thermotol- erance ... The double PCR-RFLP using ScrFI confirmed the occur- ... suade of HSP70 on defense of proteins related to respiration.

  13. Recombinant TgHSP70 Immunization Protects against Toxoplasma gondii Brain Cyst Formation by Enhancing Inducible Nitric Oxide Expression

    Directory of Open Access Journals (Sweden)

    Neide M. Silva

    2017-04-01

    Full Text Available Toxoplasma gondii is known to cause congenital infection in humans and animals and severe disease in immunocompromised individuals; consequently development of vaccines against the parasite is highly necessary. Under stress conditions, T. gondii expresses the highly immunogenic heat shock protein 70 (TgHSP70. Here, we assessed the protective efficacy of rTgHSP70 immunization combined with Alum in oral ME-49 T. gondii infection and the mechanisms involved on it. It was observed that immunized mice with rTgHSP70 or rTgHSP70 adsorbed in Alum presented a significantly reduced number of cysts in the brain that was associated with increased iNOS+ cell numbers in the organ, irrespective the use of the adjuvant. Indeed, ex vivo experiments showed that peritoneal macrophages pre-stimulated with rTgHSP70 presented increased NO production and enhanced parasite killing, and the protein was able to directly stimulate B cells toward antibody producing profile. In addition, rTgHSP70 immunization leads to high specific antibody titters systemically and a mixed IgG1/IgG2a response, with predominance of IgG1 production. Nonetheless, it was observed that the pretreatment of the parasite with rTgHSP70 immune sera was not able to control T. gondii internalization and replication by NIH fibroblast neither peritoneal murine macrophages, nor anti-rTgHSP70 antibodies were able to kill T. gondii by complement-mediated lysis, suggesting that these mechanisms are not crucial to resistance. Interestingly, when in combination with Alum, rTgHSP70 immunization was able to reduce inflammation in the brain of infected mice and in parallel anti-rTgHSP70 immune complexes in the serum. In conclusion, immunization with rTgHSP70 induces massive amounts of iNOS expression and reduced brain parasitism, suggesting that iNOS expression and consequently NO production in the brain is a protective mechanism induced by TgHSP70 immunization, therefore rTgHSP70 can be a good candidate for

  14. Localization of Hsp27 in the Rat Submandibular Gland Following the Application of Various Surgical Treatments

    International Nuclear Information System (INIS)

    Mizobe, Kenichi; Kawabe, Yoshihiro; Bando, Yasuhiko; Sakiyama, Koji; Araki, Hisao; Amano, Osamu

    2014-01-01

    Salivary glands repair and regenerate following various types of injuries and surgical procedures. However, the tissue responses induced in the contralateral glands have yet to be elucidated in detail. Hsp27, a member of the heat-shock protein (Hsp) family, is strongly expressed in physiological environments, particularly during development. Hsp27 was previously shown to play a role in the regulation of acinar cell proliferation and differentiation in the rat submandibular gland. The present study performed the following surgical treatments on the right submandibular glands of adult rats: 1) duct ligation followed by unligation after one week; 2) partial sialoadenectomy; and 3) total sialoadenectomy. Immunohistochemistry for Hsp27 and Ki67 was performed in the experimental and normal contralateral glands, and localization was histologically and morphometrically analyzed. The results obtained revealed the localization of Hsp27 to the intercalated duct in the submandibular glands of non-treated rats. The expression of Hsp27 was strongly induced in both the uninjured contralateral control glands as well as treated glands of experimental rats regardless of the surgical procedure performed. The number of Hsp27-immunopositive cells increased rapidly following surgery, and subsequently returned to the same level as that in non-treated rats after 4 weeks. However, no marked changes were observed in the number of Ki67-immunopositive proliferating cells. Therefore, the change in the number of Hsp27-immunopositive cells may have contributed to compensatory hypertrophy. The results of the present study indicate that the expression of Hsp27 in the intercalated duct in the submandibular gland may play a role in the differentiation of acinar cells

  15. Client Proteins and Small Molecule Inhibitors Display Distinct Binding Preferences for Constitutive and Stress-Induced HSP90 Isoforms and Their Conformationally Restricted Mutants.

    Directory of Open Access Journals (Sweden)

    Thomas L Prince

    Full Text Available The two cytosolic/nuclear isoforms of the molecular chaperone HSP90, stress-inducible HSP90α and constitutively expressed HSP90β, fold, assemble and maintain the three-dimensional structure of numerous client proteins. Because many HSP90 clients are important in cancer, several HSP90 inhibitors have been evaluated in the clinic. However, little is known concerning possible unique isoform or conformational preferences of either individual HSP90 clients or inhibitors. In this report, we compare the relative interaction strength of both HSP90α and HSP90β with the transcription factors HSF1 and HIF1α, the kinases ERBB2 and MET, the E3-ubiquitin ligases KEAP1 and RHOBTB2, and the HSP90 inhibitors geldanamycin and ganetespib. We observed unexpected differences in relative client and drug preferences for the two HSP90 isoforms, with HSP90α binding each client protein with greater apparent affinity compared to HSP90β, while HSP90β bound each inhibitor with greater relative interaction strength compared to HSP90α. Stable HSP90 interaction was associated with reduced client activity. Using a defined set of HSP90 conformational mutants, we found that some clients interact strongly with a single, ATP-stabilized HSP90 conformation, only transiently populated during the dynamic HSP90 chaperone cycle, while other clients interact equally with multiple HSP90 conformations. These data suggest different functional requirements among HSP90 clientele that, for some clients, are likely to be ATP-independent. Lastly, the two inhibitors examined, although sharing the same binding site, were differentially able to access distinct HSP90 conformational states.

  16. Characterization of an active dosemeter according to IEC 61526:2010

    International Nuclear Information System (INIS)

    Cardoso, J.; Santos, L.; Santos, J.A.M.; Alves, J.G.; Oliveira, C.

    2016-01-01

    The active personal dosemeter, RaySafe i2, allows the measurement and record of Hp(10) in real time, every second, via wireless technology for real-time display on a portable computer and/or a local network. The system seems particularly attractive for individual monitoring at clinical facilities where high intensity and varying radiation fields may occur, as it enables the user to acknowledge and optimize the dose and dose rate values in real time for each procedure. Prior to its use, the system was characterized at the Metrology Laboratory of Ionizing Radiation of IST-LPSR aiming at the metrological characterization of the system in accordance with IEC 61526:2010 for metrological control purposes and to verify the technical specifications stated by the manufacturer. (authors)

  17. Hsp90-downregulation influences the heat-shock response, innate immune response and onset of oocyte development in nematodes.

    Directory of Open Access Journals (Sweden)

    Julia Eckl

    Full Text Available Hsp90 is a molecular chaperone involved in the regulation and maturation of kinases and transcription factors. In Caenorhabditis elegans, it contributes to the development of fertility, maintenance of muscle structure, the regulation of heat-shock response and dauer state. To understand the consequences of Hsp90-depletion, we studied Hsp90 RNAi-treated nematodes by DNA microarrays and mass spectrometry. We find that upon development of phenotypes the levels of chaperones and Hsp90 cofactors are increased, while specific proteins related to the innate immune response are depleted. In microarrays, we further find many differentially expressed genes related to gonad and larval development. These genes form an expression cluster that is regulated independently from the immune response implying separate pathways of Hsp90-involvement. Using fluorescent reporter strains for the differentially expressed immune response genes skr-5, dod-24 and clec-60 we observe that their activity in intestinal tissues is influenced by Hsp90-depletion. Instead, effects on the development are evident in both gonad arms. After Hsp90-depletion, changes can be observed in early embryos and adults containing fluorescence-tagged versions of SEPA-1, CAV-1 or PUD-1, all of which are downregulated after Hsp90-depletion. Our observations identify molecular events for Hsp90-RNAi induced phenotypes during development and immune responses, which may help to separately investigate independent Hsp90-influenced processes that are relevant during the nematode's life and development.

  18. A Mycobacterium leprae Hsp65 mutant as a candidate for mitigating lupus aggravation in mice.

    Directory of Open Access Journals (Sweden)

    Eliana B Marengo

    Full Text Available Hsp60 is an abundant and highly conserved family of intracellular molecules. Increased levels of this family of proteins have been observed in the extracellular compartment in chronic inflammation. Administration of M. leprae Hsp65 [WT] in [NZBxNZW]F(1 mice accelerates the Systemic Lupus Erythematosus [SLE] progression whereas the point mutated K(409A Hsp65 protein delays the disease. Here, the biological effects of M. leprae Hsp65 Leader pep and K(409A pep synthetic peptides, which cover residues 352-371, are presented. Peptides had immunomodulatory effects similar to that observed with their respective proteins on survival and the combined administration of K(409A+Leader pep or K(409A pep+WT showed that the mutant forms were able to inhibit the deleterious effect of WT on mortality, indicating the neutralizing potential of the mutant molecules in SLE progression. Molecular modeling showed that replacing Lysine by Alanine affects the electrostatic potential of the 352-371 region. The number of interactions observed for WT is much higher than for Hsp65 K(409A and mouse Hsp60. The immunomodulatory effects of the point-mutated protein and peptide occurred regardless of the catalytic activity. These findings may be related to the lack of effect on survival when F(1 mice were inoculated with Hsp60 or K(409A pep. Our findings indicate the use of point-mutated Hsp65 molecules, such as the K(409A protein and its corresponding peptide, that may minimize or delay the onset of SLE, representing a new approach to the treatment of autoimmune diseases.

  19. Determination of kinetic parameters in Tl dosemeters of LiF: Mg, Cu, P + PTFE developed in the ININ

    International Nuclear Information System (INIS)

    Basurto G, B.S.

    2002-01-01

    The objective of this work, is the one of determining the kinetic parameters of the dosemeter of LiF: Mg, Cu, P + Ptfe; starting from the curves Tl obtained at being irradiated with alpha radiation (α), beta (β) and gamma (γ). As like to compare its sensitivity with each radiation type, considering the sensitivity of the TLD-100 as the unit. In the Chapter 1, the fundamental structure of the matter is described, making emphasis in the different radiation types, and their interaction with this. In the Chapter 2, the units are described but used in the dosimetry of the radiation. In the Chapter 3, the basic concepts of the phenomenon of Tl are described and those are explained characteristic of the deconvolution method to determine the kinetics of the one phenomenon. In the Chapter 4, the methodology is detailed that was used in the elaboration of this thesis work, describing the material Tl that were considered like reference, as well as the sources of ionizing radiation, with those that the dosemeters were irradiated and the equipment in the one that the curves Tl was obtained. Reference is made to the software used to carry out the deconvolution of the curves Tl that were obtained in the one experimental development. In the Chapter 5, the obtained results of this study are presented, showing the tables of homogenization of dosemeters and the reading of the same one; they are observed the curves Tl obtained to different radiation doses (alpha, beta and gamma), the intensity Tl in function of the dose. Also they are tabulated, the obtained results in the kinetic parameters of the three different study materials (TLD-100H, USA; TLD-100, USA and LiF: Mg, Cu, P + Ptfe developed in the l.N.l.N). They are analyzed shortly for each material Tl their sensitivity to the ionizing radiation as well as their kinetic parameters. The obtained results showed that the Tl dosemeters of LiF: Mg,Cu,P + Ptfe, they presented a bigger sensitivity that the TLD-100 when being

  20. Design and Construction of a Cloning Vector Containing the hspX Gene of Mycobacterium tuberculosis.

    Science.gov (United States)

    Yaghoubi, Atieh; Aryan, Ehsan; Zare, Hosna; Alami, Shadi; Teimourpour, Roghayeh; Meshkat, Zahra

    2016-10-01

    Tuberculosis (TB) is a major cause of death worldwide. Finding an effective vaccine against TB is the best way to control it. Several vaccines against this disease have been developed but none are completely protective. The aim of this study was to design and construct a cloning vector containing the Mycobacterium tuberculosis (M. tuberculosis) heat shock protein X (hspX) . First, an hspX fragment was amplified by PCR and cloned into plasmid pcDNA3.1(+) and recombinant vector was confirmed. A 435 bp hspX fragment was isolated. The fragment was 100% homologous with hspX of M. tuberculosis strain H37Rv in GenBank. In this study, the cloning vector pcDNA3.1(+), containing a 435-bp hspX fragment of M. tuberculosis , was constructed. This could be used as a DNA vaccine to induce immune responses in animal models in future studies.

  1. A rat retinal damage model predicts for potential clinical visual disturbances induced by Hsp90 inhibitors

    International Nuclear Information System (INIS)

    Zhou, Dan; Liu, Yuan; Ye, Josephine; Ying, Weiwen; Ogawa, Luisa Shin; Inoue, Takayo; Tatsuta, Noriaki; Wada, Yumiko; Koya, Keizo; Huang, Qin; Bates, Richard C.; Sonderfan, Andrew J.

    2013-01-01

    In human trials certain heat shock protein 90 (Hsp90) inhibitors, including 17-DMAG and NVP-AUY922, have caused visual disorders indicative of retinal dysfunction; others such as 17-AAG and ganetespib have not. To understand these safety profile differences we evaluated histopathological changes and exposure profiles of four Hsp90 inhibitors, with or without clinical reports of adverse ocular effects, using a rat retinal model. Retinal morphology, Hsp70 expression (a surrogate marker of Hsp90 inhibition), apoptotic induction and pharmacokinetic drug exposure analysis were examined in rats treated with the ansamycins 17-DMAG and 17-AAG, or with the second-generation compounds NVP-AUY922 and ganetespib. Both 17-DMAG and NVP-AUY922 induced strong yet restricted retinal Hsp70 up-regulation and promoted marked photoreceptor cell death 24 h after the final dose. In contrast, neither 17-AAG nor ganetespib elicited photoreceptor injury. When the relationship between drug distribution and photoreceptor degeneration was examined, 17-DMAG and NVP-AUY922 showed substantial retinal accumulation, with high retina/plasma (R/P) ratios and slow elimination rates, such that 51% of 17-DMAG and 65% of NVP-AUY922 present at 30 min post-injection were retained in the retina 6 h post-dose. For 17-AAG and ganetespib, retinal elimination was rapid (90% and 70% of drugs eliminated from the retina at 6 h, respectively) which correlated with lower R/P ratios. These findings indicate that prolonged inhibition of Hsp90 activity in the eye results in photoreceptor cell death. Moreover, the results suggest that the retina/plasma exposure ratio and retinal elimination rate profiles of Hsp90 inhibitors, irrespective of their chemical class, may predict for ocular toxicity potential. - Highlights: • In human trials some Hsp90 inhibitors cause visual disorders, others do not. • Prolonged inhibition of Hsp90 in the rat eye results in photoreceptor cell death. • Retina/plasma ratio and retinal

  2. Re-Establishment of Standard Radiation Qualities for Calibration of Dosemeter in Diagnostic Radiology - RQR Series

    International Nuclear Information System (INIS)

    Asmaliza Hashim; Norhayati Abdullah; Mohd Firdaus Abd Rahman

    2016-01-01

    After repairing the high voltage (HV) generator for Philips MG165 X-Ray Machine, the reestablishment of the standard radiation qualities has been done at Medical Physics Calibration Laboratory to meet the IEC and IAEA standard. Standard radiation qualities are the important criteria for calibration of dosemeter in diagnostic radiology. Standard radiation qualities are defined as the added filtration needed to produce and the half value layer (HVL) of the beam for specifies x-ray tube kilo voltage (kV). For calibration of dosemeter in diagnostic radiology, standard radiation qualities RQR represent the beam incident on the patient in general radiography, fluoroscopy and dental application. The HVL were measured using PTW ion chamber of volume 1 cm"3 with PTW electrometer and aluminium filter with 99.9 % purity was used as additional filter for RQR and filter for HVL. The first establishment of standard radiation qualities was made in 2009 for the radiation qualities of RQR. The results of additional filter and 1st HVL from 2009 to 2016 will be discussed further in paper. The ratios of the measured HVL to the standard IEC HVL value for the RQR series also described in this paper. The details of the measurement and the results are described in this paper. (author)

  3. The former tests realized to a personal neutron dosemeter based on solid nuclear tracks detector; Primeras pruebas realizadas a un dosimetro personal de neutrones basado en detectores solidos de trazas nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Camacho, M.E.; Tavera, L.; Balcazar, M. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    Due to the increase in the use of neutron radiation a personal neutron dosemeter based on solid nuclear tracks detector (DSTN) was designed and constructed. The personal dosemeter design consists of three arrangements. The first one consists of a plastic nuclear tracks detector (LR115 or CR39) in contact with a LiF pellet. The second one is the same that above but it placed among two cadmium pellets and, the third one is formed by the alone detector without converter neither neutron absorber. The three arrangements are placed inside a plastic porta detector hermetically closed to avoid the bottom produced by environmental radon whichever both detectors (LR115 and CR39) are sensitive. In this work the former tests realized to that dosemeter are presented. (Author)

  4. Effect of some parameters in the response of the Perspex 3042, Lot L amber dosemeters; Efectos de algunos parametros en la respuesta de los dosimetros ambar Perspex 3042, Lote L

    Energy Technology Data Exchange (ETDEWEB)

    Prieto M, E.F.; Barrera G, G. [Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear (CEADEN). Calle 30, No. 502, esq. 5ta. Avenida, Playa, Ciudad de La Habana (Cuba)]. e-mail: efprieto@ceaden.edu.cu

    2004-07-01

    The answer of the dosimetric systems is affected by several factors, for what should know as these factors they influence in each one of the different dosimetric systems and by this way to minimize its effect in the value of the absorbed dose and to obtain exact dose values. One of the dosimetric systems more used in the high dose dosimetry like routine dosemeter for the control of the irradiation process are the Perspex dosemeters, for their speed in the obtaining the information, their easy manipulation and the precision that they present. To this dosemeters group they belong the same as the Red and Clear the Amber, which are adequate for the measurement of the radiation dose in the range of high doses. The objective of the present work is to obtain the calibration curves of the dosemeters Amber Perspex 3042, Lot L under our work conditions, like they are the irradiation temperatures and of storage and to know the influence of the rate dose in the value of the absorbed dose for different measurement wavelengths, as well as, the relationship among the one post-irradiation time and the specific absorbance value induced in function of the absorbed dose. (Author)

  5. Investigation of dosimetric characteristics of the high sensitivity LiF:Mg,Cu,P Thermoluminescent Dosemeter and its applications in diagnostic radiology - a review

    International Nuclear Information System (INIS)

    Fung, K.L.

    2004-01-01

    This study investigated the dosimetric properties of the high sensitivity TLD (Thermoluminescent Dosemeter) of LiF:Mg,Cu,P and its applications in diagnostic radiology. A reproducible readout and annealing regime for this high sensitivity TLD was developed in the initial part of this study with the newly installed automatic TLD Reader system. Basic dosimetric characteristics of this T.L. dosemeter were then investigated. This paved the foundation for subsequent selected novel application studies in diagnostic radiology. This study exploits the favourable dosimetric properties of these T.L. dosemeters in some selected novel dosimetric applications in diagnostic radiology with an anthropomorphic phantom. The applications studied in radiological procedures included: dose reduction in lumbar spine radiography utilizing the 'anode heel effect'; gonad dose variation with kV p in chest radiography; foetal dose comparison between computed tomography (CT) and computed radiography (CR) in X-ray pelvimetry; lens dose reduction with bismuth eye-shields in CT brain studies; foetal dose assessment of early pregnancy in common high risk radiological examinations. It is anticipated that the unique and favourable dosimetric performance of LiF:Mg,Cu,P T.L. phosphor will be exploited further in measurements of low level dose received by patients and staff in diagnostic radiological procedures such as paediatric X-ray examinations

  6. Investigation of dosimetric characteristics of the high sensitivity LiF:Mg,Cu,P Thermoluminescent Dosemeter and its applications in diagnostic radiology - a review

    Energy Technology Data Exchange (ETDEWEB)

    Fung, K.L. E-mail: orkarl@polyu.edu.hk

    2004-05-01

    This study investigated the dosimetric properties of the high sensitivity TLD (Thermoluminescent Dosemeter) of LiF:Mg,Cu,P and its applications in diagnostic radiology. A reproducible readout and annealing regime for this high sensitivity TLD was developed in the initial part of this study with the newly installed automatic TLD Reader system. Basic dosimetric characteristics of this T.L. dosemeter were then investigated. This paved the foundation for subsequent selected novel application studies in diagnostic radiology. This study exploits the favourable dosimetric properties of these T.L. dosemeters in some selected novel dosimetric applications in diagnostic radiology with an anthropomorphic phantom. The applications studied in radiological procedures included: dose reduction in lumbar spine radiography utilizing the 'anode heel effect'; gonad dose variation with kV{sub p} in chest radiography; foetal dose comparison between computed tomography (CT) and computed radiography (CR) in X-ray pelvimetry; lens dose reduction with bismuth eye-shields in CT brain studies; foetal dose assessment of early pregnancy in common high risk radiological examinations. It is anticipated that the unique and favourable dosimetric performance of LiF:Mg,Cu,P T.L. phosphor will be exploited further in measurements of low level dose received by patients and staff in diagnostic radiological procedures such as paediatric X-ray examinations.

  7. Cloning, characterization, and heat stress-induced redistribution of a protein homologous to human hsp27 in the zebrafish Danio rerio

    International Nuclear Information System (INIS)

    Mao Li; Bryantsev, Anton L.; Chechenova, Maria B.; Shelden, Eric A.

    2005-01-01

    Hsp27 is a small heat shock protein (shsp) regulating stress tolerance and increasingly thought to play roles in tissue homeostasis and differentiation. The zebrafish Danio rerio is an important model for the study of developmental processes, but little is known regarding shsps in this animal. Here, we report the sequence, expression, regulation, and function of a zebrafish protein (zfHsp27) homologous to human Hsp27. zfHsp27 contains three conserved phosphorylatable serines and a cysteine important for regulation of apoptosis, but it lacks much of a C-terminal tail domain and shows low homology in two putative actin interacting domains that are features of mammalian Hsp27. zfHsp27 mRNA is most abundant in adult skeletal muscle and heart and is upregulated during early embryogenesis. zfHsp27 expressed in mammalian fibroblasts was phosphorylated in response to heat stress and anisomycin, and this phosphorylation was prevented by treatment with SB202190, an inhibitor of p38 MAPK. Expression of zfHsp27 and human Hsp27 in mammalian fibroblasts promoted a similar degree of tolerance to heat stress. zfHsp27 fusion proteins entered the nucleus and associated with the cytoskeleton of heat stressed cells in vitro and in zebrafish embryos. These results reveal conservation in regulation and function of mammalian and teleost Hsp27 proteins and define zebrafish as a new model for the study of Hsp27 function

  8. Selection and Characterization of Single Chain Antibody Fragments Specific for Hsp90 as a Potential Cancer Targeting Molecule

    Directory of Open Access Journals (Sweden)

    Edyta Petters

    2015-08-01

    Full Text Available Heat shock proteins play an essential role in facilitating malignant transformation and they have been recognized as important factors in human cancers. One of the key elements of the molecular chaperones machinery is Hsp90 and it has recently become a target for anticancer therapeutic approaches. The potential and importance of Hsp90-directed agents becomes apparent when one realizes that disruption of Hsp90 function may influence over 200 oncogenic client proteins. Here, we described the selection and characterization of Hsp90-specific antibody fragments from commercially available Tomlinson I and J phage display libraries. The affinities of Hsp90-binding scFv variants were measured using SPR method. Then, based on the best clone selected, we performed the affinity maturation procedure and obtained valuable Hsp90-specific clones. The selected binders were expressed and applied for immunostaining, ELISA and SPR analysis using model cancer cell lines. All performed experiments confirmed the ability of selected antibodies to interact with the Hsp90. Therefore, the presented Hsp90-specific scFv, might be a starting point for the development of a novel antibody-based strategy targeting cancer.

  9. Downregulation of the Hsp90 system causes defects in muscle cells of Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Andreas M Gaiser

    Full Text Available The ATP-dependent molecular chaperone Hsp90 is required for the activation of a variety of client proteins involved in various cellular processes. Despite the abundance of known client proteins, functions of Hsp90 in the organismal context are not fully explored. In Caenorhabditis elegans, Hsp90 (DAF-21 has been implicated in the regulation of the stress-resistant dauer state, in chemosensing and in gonad formation. In a C. elegans strain carrying a DAF-21 mutation with a lower ATP turnover, we observed motility defects. Similarly, a reduction of DAF-21 levels in wild type nematodes leads to reduced motility and induction of the muscular stress response. Furthermore, aggregates of the myosin MYO-3 are visible in muscle cells, if DAF-21 is depleted, implying a role of Hsp90 in the maintenance of muscle cell functionality. Similar defects can also be observed upon knockdown of the Hsp90-cochaperone UNC-45. In life nematodes YFP-DAF-21 localizes to the I-band and the M-line of the muscular ultrastructure, but the protein is not stably attached there. The Hsp90-cofactor UNC-45-CFP contrarily can be found in all bands of the nematode muscle ultrastructure and stably associates with the UNC-54 containing A-band. Thus, despite the physical interaction between DAF-21 and UNC-45, apparently the two proteins are not always localized to the same muscular structures. While UNC-45 can stably bind to myofilaments in the muscular ultrastructure, Hsp90 (DAF-21 appears to participate in the maintenance of muscle structures as a transiently associated diffusible factor.

  10. Activation of catalase activity by a peroxisome-localized small heat shock protein Hsp17.6CII.

    Science.gov (United States)

    Li, Guannan; Li, Jing; Hao, Rong; Guo, Yan

    2017-08-20

    Plant catalases are important antioxidant enzymes and are indispensable for plant to cope with adverse environmental stresses. However, little is known how catalase activity is regulated especially at an organelle level. In this study, we identified that small heat shock protein Hsp17.6CII (AT5G12020) interacts with and activates catalases in the peroxisome of Arabidopsis thaliana. Although Hsp17.6CII is classified into the cytosol-located small heat shock protein subfamily, we found that Hsp17.6CII is located in the peroxisome. Moreover, Hsp17.6CII contains a novel non-canonical peroxisome targeting signal 1 (PTS1), QKL, 16 amino acids upstream from the C-terminus. The QKL signal peptide can partially locate GFP to peroxisome, and mutations in the tripeptide lead to the abolishment of this activity. In vitro catalase activity assay and holdase activity assay showed that Hsp17.6CII increases CAT2 activity and prevents it from thermal aggregation. These results indicate that Hsp17.6CII is a peroxisome-localized catalase chaperone. Overexpression of Hsp17.6CII conferred enhanced catalase activity and tolerance to abiotic stresses in Arabidopsis. Interestingly, overexpression of Hsp17.6CII in catalase-deficient mutants, nca1-3 and cat2 cat3, failed to rescue their stress-sensitive phenotypes and catalase activity, suggesting that Hsp17.6CII-mediated stress response is dependent on NCA1 and catalase activity. Overall, we identified a novel peroxisome-located catalase chaperone that is involved in plant abiotic stress resistance by activating catalase activity. Copyright © 2017 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.

  11. Over-expression of Arabidopsis DnaJ (Hsp40) contributes to NaCl ...

    African Journals Online (AJOL)

    Over-expression of Arabidopsis DnaJ (Hsp40) contributes to NaCl-stress tolerance. Z Zhichang, Z Wanrong, Y Jinping, Z Jianjun, LZL Xufeng, Y Yang. Abstract. DnaJ (Hsp40), a heat shock protein, is a molecular chaperones responsive to various environmental stress. To analyze the protective role of DnaJ, we obtained ...

  12. Expression of Helicobacter pylori hspA Gene in Lactococcus lactis NICE System and Experimental Study on Its Immunoreactivity

    Directory of Open Access Journals (Sweden)

    Xiao-Juan Zhang

    2015-01-01

    Full Text Available Aim. The aim of this study was to develop an oral Lactococcus lactis (L. lactis vaccine against Helicobacter pylori (H. pylori. Methods. After L. lactis NZ3900/pNZ8110-hspA was constructed, growth curves were plotted to study whether the growth of recombinant L. lactis was affected after hspA was cloned into L. lactis and whether the growth of empty bacteria, empty plasmid bacteria, and recombinant L. lactis was affected by different concentrations of Nisin; SDS-PAGE and Western blot were adopted, respectively, to detect the HspA expressed by recombinant L. lactis and its immunoreactivity. Results. There was no effect observed from the growth curve after exogenous gene hspA was cloned into L. lactis NZ3900; different concentrations of Nisin did not affect the growth of NZ3900 and NZ3900/pNZ8110, while different concentrations of Nisin inhibited the growth of NZ3900/pNZ8110-hspA except 10 ng/mL Nisin. No HspA strip was observed from SDS-PAGE. Western blot analysis showed that HspA expressed by recombinant bacteria had favorable immunoreactivity. Conclusion. The growth of recombinant L. lactis was suppressed even though a small amount of HspA had been induced to express. Therefore recombinant L. lactis only express HspA which was not suitable to be oral vaccine against Helicobacter pylori.

  13. Expression dynamics of HSP70 during chronic heat stress in Tharparkar cattle.

    Science.gov (United States)

    Bharati, Jaya; Dangi, S S; Chouhan, V S; Mishra, S R; Bharti, M K; Verma, V; Shankar, O; Yadav, V P; Das, K; Paul, A; Bag, S; Maurya, V P; Singh, G; Kumar, P; Sarkar, M

    2017-06-01

    Six male Tharparkar cattle aged 2-3 years were selected for the study. The animals were acclimatized in the psychrometric chamber at thermoneutral zone (TNZ) for 15 days and then exposed to 42 °C temperature up to 23 days followed by 12 days of recovery period. Physiological responses were estimated, and peripheral blood mononuclear cells (PBMCs) were isolated at TNZ on day 1, day 5, and day 12; after 6 h of heat stress exposure on day 16 to day 20, day 25, day 30, day 32, day 34, day 36, and day 38; and a recovery period on day 45 and day 50. The PBMCs were cultured to study the effect of thermal challenge on HSP70 messenger RNA (mRNA) expression pattern at different temperature-time combinations. The mRNA and protein expression of HSP70 in PBMCs along with serum extracellular HSP70 (eHSP70) was increased (P cattle and the biphasic expression pattern may be providing a second window of protection during chronic heat stress.

  14. Structure of a new crystal form of human Hsp70 ATPase domain.

    Science.gov (United States)

    Osipiuk, J; Walsh, M A; Freeman, B C; Morimoto, R I; Joachimiak, A

    1999-05-01

    Hsp70 proteins are highly conserved proteins induced by heat shock and other stress conditions. An ATP-binding domain of human Hsp70 protein has been crystallized in two major morphological forms at pH 7.0 in the presence of PEG 8000 and CaCl2. Both crystal forms belong to the orthorhombic space group P212121, but show no resemblance in unit-cell parameters. Analysis of the crystal structures for both forms shows a 1-2 A shift of one of the subdomains of the protein. This conformational change could reflect a 'natural' flexibility of the protein which might be relevant to ATP binding and may facilitate the interaction of other proteins with Hsp70 protein.

  15. The Stoichiometric Interaction of the Hsp90-Sgt1-Rar1 Complex by CD and SRCD Spectroscopy

    Directory of Open Access Journals (Sweden)

    Giuliano Siligardi

    2018-01-01

    Full Text Available While the molecular details by which Hsp90 interacts with Sgt1 and Rar1 were previously described the exact stoichiometric complex that is formed remains elusive. Several possibilities remain that include two asymmetric complexes, Sgt12-Hsp902-Rar12 (two molecules of Sgt1 and Rar1 and one Hsp90 dimer or Sgt12-Hsp902-Rar11 (with a single Rar1 molecule and an asymmetric complex (Sgt11-Hsp902-Rar11. The Hsp90-mediated activation of NLR receptors (Nucleotide-binding domain and Leucine-rich Repeat in the innate immunity of both plants and animals is dependent on the co-chaperone Sgt1 and in plants on Rar1, a cysteine- and histidine-rich domain (CHORD-containing protein. The exact stoichiometry of such a complex may have a direct impact on NLR protein oligomerization and thus ultimately on the mechanism by which NLRs are activated. CD spectroscopy was successfully used to determine the stoichiometry of a ternary protein complex among Hsp90, Sgt1, and Rar1 in the presence of excess ADP. The results indicated that a symmetric Sgt12-Hsp902-Rar11 complex was formed that could allow two NLR molecules to simultaneously bind. The stoichiometry of this complex has implications on, and might promote, the dimerization of NLR proteins following their activation.

  16. SGT, a Hsp90β binding partner, is accumulated in the nucleus during cell apoptosis

    International Nuclear Information System (INIS)

    Yin Hongyan; Wang Hanzhou; Zong Hongliang; Chen Xiaoning; Wang Yanlin; Yun Xiaojing; Wu Yihong; Wang Jiadong; Gu Jianxin

    2006-01-01

    In this study, we reported that small glutamine-rich TPR-containing protein (SGT) interacted with not only Hsp90α but also Hsp90β. Confocal analysis showed that treatment of cells with Hsp90-specific inhibitor geldanamycin (GA) disrupted the interaction of SGT with Hsp90β and this contributed to the increase of nuclear localization of SGT in HeLa cells. The increased nuclear localization of SGT was further confirmed by the Western blotting in GA-treated HeLa cells and H1299 cells. In our previous study, SGT was found to be a new pro-apoptotic factor, so we wondered whether the sub-cellular localization of SGT was related with cell apoptosis. By confocal analysis we found that the nuclear import of SGT was significantly increased in STS-induced apoptotic HeLa cells, which implied that the sub-cellular localization of SGT was closely associated with Hsp90β and apoptosis

  17. Design and Construction of a Cloning Vector Containing the hspX Gene of Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Atieh Yaghoubi

    2016-10-01

    Full Text Available Background: Tuberculosis (TB is a major cause of death worldwide. Finding an effective vaccine against TB is the best way to control it. Several vaccines against this disease have been developed but none are completely protective. The aim of this study was to design and construct a cloning vector containing the Mycobacterium tuberculosis (M. tuberculosis heat shock protein X (hspX. Methods: First, an hspX fragment was amplified by PCR and cloned into plasmid pcDNA3.1(+ and recombinant vector was confirmed. Results: A 435 bp hspX fragment was isolated. The fragment was 100% homologous with hspX of M. tuberculosis strain H37Rv in GenBank. Conclusions: In this study, the cloning vector pcDNA3.1(+, containing a 435-bp hspX fragment of M. tuberculosis, was constructed. This could be used as a DNA vaccine to induce immune responses in animal models in future studies.

  18. Application of low-cost Gallium Arsenide light-emitting-diodes as kerma dosemeter and fluence monitor for high-energy neutrons

    International Nuclear Information System (INIS)

    Mukherjee, B.; Simrock, S.; Khachan, J.; Rybka, D.; Romaniuk, R.

    2007-01-01

    Displacement damage (DD) caused by fast neutrons in unbiased Gallium Arsenide (GaAs) light emitting diodes (LED) resulted in a reduction of the light output. On the other hand, a similar type of LED irradiated with gamma rays from a 60 Co source up to a dose level in excess of 1.0 kGy (1.0 x 10 5 rad) was found to show no significant drop of the light emission. This phenomenon was used to develop a low cost passive fluence monitor and kinetic energy released per unit mass dosemeter for accelerator-produced neutrons. These LED-dosemeters were used to assess the integrated fluence of photoneutrons, which were contaminated with a strong Bremsstrahlung gamma-background generated by the 730 MeV superconducting electron linac driving the free electron laser in Hamburg (FLASH) at Deutsches Elektronen-Synchrotron. The applications of GaAs LED as a routine neutron fluence monitor and DD precursor for the electronic components located in high-energy accelerator environment are highlighted. (authors)

  19. Expression of HSP27, HSP72 and MRP proteins in in vitro co-culture of colon tumour cell spheroids with normal cells after incubation with rhTGF- beta1 and/or CPT-11.

    Science.gov (United States)

    Paduch, Roman; Jakubowicz-Gil, Joanna; Kandefer-Szerszen, Martyna

    2009-12-01

    We studied the expression of inducible heat shock protein (HSP27, HSP72) and multidrug-resistance protein (MRP) in co-cultures of human colon carcinoma cell spheroids obtained from different grades of tumour with normal human colon epithelium, myofibroblast and endothelial cell monolayers. We also measured the influence of recombinant human transforming growth factor beta1 (rhTGF-beta1) and camptothecin (CPT-11), added as single agents or in combination, on the levels of the HSPs, MRP, interleukin (IL)-6 and nitric oxide (NO). An immunoblotting analysis with densitometry showed that rhTGF-beta1 and/or CPT-11 increased HSP27, HSP72 and MRP expression in tumour cells and myofibroblasts, as well as in co-cultures compared with appropriate controls. By contrast, in colonic epithelium, inhibition of HSPs and MRP was comparable with that of the control. In endothelial cells, HSP72 was undetectable. Direct interaction of colon tumour spheroids with normal myofibroblasts caused a significant, tumour-grade dependent increase in IL-6 production. Production of IL-6 was significantly lowered by rhTGF-beta1 and/or CPT-11. Tumour cell spheroids cultivated alone produced larger amounts of NO than normal cells. In co-culture, the level of the radical decreased compared with the sum of NO produced by the monocultures of the two types of cells. rhTGF-beta1 and/or CPT-11 decreased NO production both in tumour and normal cell monocultures and their co-cultures. In conclusion, direct interactions between tumour and normal cells influence the expression of HSP27, HSP72 and MRP, and alter IL-6 and NO production. rhTGF-beta1 and/or CPT-11 may potentate resistance to chemotherapy by increasing HSP and MRP expression but, on the other hand, they may limit tumour cell spread by decreasing the level of some soluble mediators of inflammation (IL-6 and NO).

  20. Caracterización in silico de las proteínas del choque térmico Hsp70 y Hsp90 deBemisia tabaci (Hemiptera: Aleyrodidae y su posible actividad adaptativa

    Directory of Open Access Journals (Sweden)

    Eneida Torres Cabra

    2014-06-01

    Full Text Available La mosca blanca, Bemisia tabaci (Hemiptera: Aleyrodidae es una de las plagas más destructivas e invasivas en el mundo, ataca una gran cantidad de cultivos. Se adapta fácilmente a plantas hospederas y a nuevas regiones geográficas, lo que sugiere el desarrollo de mecanismos de control a daños producidos por factores estresantes. Las proteínas Hsp se expresanen los organismos como mecanismo de defensa, actúan como chaperonas en el correcto ensamblaje de las proteínas. En este estudio se realizó una caracterizaciónin silico de las proteínas Hsp70 y Hsp90 de B. tabaci, secuencias obtenidas de NCBI. La determinaciónde los perfiles de hidrofobicidad, polaridad, accesibilidady flexibilidad se obtuvieron con “ProScale” de ExPASy, el perfil de antigenicidad con JaMBW. La secuencia aminoacídica se analizó con GOR IV y SOPMA y la composición de aminoácidos con ProtParam. Para analizar el peso molecular, índice deinestabilidad, índice alifático y gradiente hidropático,con GRAVY. La estructura terciaria se obtuvo con HHpred, y ESyPred3D. Para validar las estructuras 3D se utilizó Procheck, What_check y errat. Hsp70 y Hsp90 de B. tabaci presentan valores bajos de hidrofobicidady altos de polaridad, flexibilidad y accesibilidad, características que le permiten a las proteínas extender su capacidad como chaperonas. La Hsp70tiene una estructura secundaria compuesta por 41-45% alfa hélices, 30-43% coil y menos del 6% en hoja plegada y la Hsp90 por 52 y 53% hélices, 26-34% coily 6% hoja plegada. Las Hsp juegan un rol importante en los insectos debido a su tamaño y corto ciclo de vida, pues la temperatura influye en su distribución y abundancia.