Rotational total skin electron irradiation with a linear accelerator

Science.gov (United States)

Evans, Michael D.C.; Devic, Slobodan; Parker, William; Freeman, Carolyn R.; Roberge, David; Podgorsak, Ervin B.

2008-01-01

The rotational total skin electron irradiation (RTSEI) technique at our institution has undergone several developments over the past few years. Replacement of the formerly used linear accelerator has prompted many modifications to the previous technique. With the current technique, the patient is treated with a single large field while standing on a rotating platform, at a source‐to‐surface distance of 380 cm. The electron field is produced by a Varian 21EX linear accelerator using the commercially available 6 MeV high dose rate total skin electron mode, along with a custom‐built flattening filter. Ionization chambers, radiochromic film, and MOSFET (metal oxide semiconductor field effect transistor) detectors have been used to determine the dosimetric properties of this technique. Measurements investigating the stationary beam properties, the effects of full rotation, and the dose distributions to a humanoid phantom are reported. The current treatment technique and dose regimen are also described. PACS numbers: 87.55.ne, 87.53.Hv, 87.53.Mr

SU-F-T-82: Dosimetric Evaluation of a Shield Used for Hemi-Body Skin Electron Irradiation

Energy Technology Data Exchange (ETDEWEB)

Rivers, C; Singh, A [Roswell Park Cancer Institute, Buffalo, NY (United States); AlDahlawi, I; Wang, I; Podgorsak, M [Roswell Park Cancer Institute, Buffalo, NY (United States); State University of New York at Buffalo, Buffalo, NY (United States)

2016-06-15

Purpose: We had several mycosis fungoides patients with a limited disease to about half of the skin surface. A custom-made plywood shield was used to protect the non-targeted skin region with our total skin electron irradiation (TSEI) technique. We report a dosimetric evaluation for our “hemi-body” skin electron irradiation technique. Methods: The technique is similar to our clinical total skin electron irradiation (TSEI), performed with a six-pair dual field (Stanford technique) at an extended source-to-skin distance (SSD) of 377 cm, with the addition of a plywood shield placed 50 cm from the patient. The shield is made of three layers of standard 5/8″ thick plywood (total thickness of 4.75 cm) that are clamped securely on an adjustable-height stand. Gafchromic EBT3 films were used in assessing the shield’s transmission factor and the extend of the dose penumbra region. To verify the dose delivered for hemi-body skin radiation in a real patient treatment, in-vivo dosimetry using Gafchromic EBT3 films were performed. Film pieces were taped on the patient skin to measure the dose received during the first two fractions, placed on the forehead and upper body (shielded region); and also at the level of pelvic area, left thigh, and left ankle. Results: The shield transmission factor was found to be 10%, and the width of the penumbra (80-to-20% dose fall-off) was about 12 cm. In-vivo dosimetry of a real case confirmed the expected shielded area dose. Conclusion: Hemi-Body skin electron irradiation at an extended SSD is feasible with the addition of a plywood shield at a distance from patient skin. The penumbra dose region and the shield’s transmission factor should be evaluated prior to clinical use. We have treated several hemi-body skin patients with our custom-made plywood shield, the current patient measurements are representative of these for other patients as well.

Electron spin resonance characterization of radical components in irradiated black pepper skin and core

International Nuclear Information System (INIS)

Yamaoki, Rumi; Kimura, Shojiro; Ohta, Masatoshi

2011-01-01

Characteristics of free radical components of irradiated black pepper fruit (skin) and the pepper seed (core) were analyzed using electron spin resonance. A weak signal near g=2.005 was observed in black pepper before irradiation. Complex spectra near g=2.005 with three lines (the skin) or seven lines (the core) were observed in irradiated black pepper (both end line width; ca. 6.8 mT). The spectral intensities decreased considerably at 30 days after irradiation, and continued to decrease steadily thereafter. The spectra simulated on the basis of the content and the stability of radical components derived from plant constituents, including fiber, starch, polyphenol, mono- and disaccharide, were in good agreement with the observed spectra. Analysis showed that the signal intensities derived from fiber in the skin for an absorbed dose were higher, and the rates of decrease were lower, than that in the core. In particular, the cellulose radical component in the skin was highly stable. - Highlights: → We identified the radical components in irradiated black pepper skin and core. → The ESR spectra near g=2.005 with 3-7 lines were emerged after irradiation. → Spectra simulated basing on the content and the stability of radical from the plant constituents. → Cellulose radical component in black pepper skin was highly stable. → Single signal near g=2.005 was the most stable in black pepper core.

An experimental studies of skin autograft in irradiated bed

International Nuclear Information System (INIS)

Ueda, Minoru

1981-01-01

Effects of irradiation to revascularization and skin grafting were studied. Wistar rats were irradiated with 1000, 2000, and 3000 rad of x-ray. One 2, 4, 6, 8, 12, and 24 weeks after irradiation each group, consisted of 10 rats, was compared with that of 34 untreated rats. A new score system of skin reaction was proposed. The highest moist skin reaction was observed after 2 weeks in 3 irradiated groups. In the 2000 and 3000 rad groups, the acute reaction appeared with 1 week latent period and recovered in 8 weeks followed by marked skin atrophy and epilation, while in the 1000 rad group complete recovery was observed in 3 weeks without late squlae. In order to carry out microangiography, a new device to inject the contrast medium at constant temperature and pressure was used. Marked inflammation was observed in 4 weeks, began to recover in 4 weeks, and hypovascular area appeared in 8 weeks. As for the blood area density, no variation was found for the 1000 rad group. However, in the 2000 and 3000 rad groups, the highest density was observed in 2 weeks and decreased after 8 weeks to that lower than the control. Revascularization after the skin grafting was followed by microangiography. In the control group, primary and secondary revascularization was observed one and 3 days after transplantation. As for the 3000 rad groups both revascularizations were hardly recognized when transplanted 8 weeks after irradiation. The optimum time for skin grafting was found to be acute or subacute period of the vascular damage. (Nakanishi, T.)

Dose characteristics of total-skin electron-beam irradiation with six-dual electron fields

International Nuclear Information System (INIS)

Choi, Tae Jin; Kim, Jin Hee; Kim, Ok Bae

1998-01-01

To obtain the uniform dose at limited depth to entire surface of the body, the dose characteristics of degraded electron beam of the large target-skin distance and the dose distribution of the six-dual electron fields were investigated. The experimental dose distributions included the depth dose curve, spatial dose and attenuated electron beam were determined with 300 cm of Target-Skin Distance (TSD) and full collimator size (35x35 cm 2 on TSD 100 cm) in 4 MeV electron beam energy. Actual collimated field size of 105 cmx105 cm at the distance of 300 cm could include entire hemibody. A patient was standing on step board with hands up and holding the pole to stabilize his/her positions for the six-dual fields technique. As a scatter-degrader, 0.5 cm of acrylic plate was inserted at 20 cm from the body surface on the electron beam path to induce ray scattering and to increase the skin dose. The Full Width at Half Maximum(FWHM) of dose profile was 130 cm in large field of 105x105 cm 2 . The width of 100±10% of the resultant dose from two adjacent fields which were separated at 25 cm from field edge for obtaining the dose uniformity was extended to 186 cm. The depth of maximum dose lies at 5 mm and the 80% depth dose lies between 7 and 8 mm for the degraded electron beam by using the 0.5 cm thickness of acrylic absorber. Total skin electron beam irradiation (TSEBI) was carried out using the six dual fields has been developed at Stanford University. The dose distribution in TSEBI showed relatively uniform around the flat region of skin except the protruding and deeply curvatured portion of the body, which showed excess of dose at the former and less dose at the latter. The percent depth dose, profile curves and superimposed dose distribution were investigated using the degraded using the degraded electron beam through the beam absorber. The dose distribution obtained by experiments of TSEBI showed within±10% difference excepts the protruding area of skin which needs a

Revascularization of autogenous skin grafts placed on irradiated tissue

International Nuclear Information System (INIS)

Ueda, M.; Torii, S.; Kaneda, T.; Oka, T.

1982-01-01

Vascular changes in rat skin after irradiation were examined microangiographically. Revascularization of the skin transplanted during the chronic stage after irradiation was also studied. The results obtained through these examinations revealed higher vascular densities at the acute and the subacute stages, and low values at the chronic stages compared with those of the control. Furthermore, when the skin grafts were transplanted to the irradiated beds in the chronic stage, primary revascularization was scant, and the inhibited capillary proliferation in the recipient sites prevented new vessel penetration. This explains why grafts transplanted to previously irradiated beds fail to survive

Postoperative irradiation after reconstructive surgery: comparative study of radiosensitivity between free-skin grafts and skin flaps

International Nuclear Information System (INIS)

Sumi, Y.; Ueda, M.; Kaneda, T.; Oka, T.; Torii, S.; Sakuma, S.

1984-01-01

Radiation effects after reconstructive surgery (free-skin grafts and skin flaps) were studied in the rat, and the optimum time for irradiation was determined. The radiosensitivity of both free-skin grafts and skin flaps showed the same trend depending on time of irradiation after operation. The grafts or flaps irradiated in the hypervascular stage showed severe reactions to irradiation, whereas those irradiated in the hypovascular stage showed milder reactions in gross and microangiographic observation. Vascular damage should be given primary consideration when deciding the proper time for irradiation after reconstructive surgery. In general, free-skin grafts showed more severe reactions than skin flaps, especially in the grafts irradiated in the early stage after operation. The experimental results of this study cannot be readily transferred to a clinical setting, but they suggest that postoperative irradiation could be begun 3 to 4 weeks after operation with respect to graft or flap survival, and the results of the clinical cases almost coincide with these experimental results

Isolation and identification of previtamin D3 from the skin of rats exposed to ultraviolet irradiation

International Nuclear Information System (INIS)

Holick, M.F.; Richtand, N.M.; McNeill, S.C.; Holick, S.A.; Frommer, J.E.; Henley, J.W.; Potts, J.T. Jr.

1979-01-01

The process of the photolytic activation of vitamin D precursor(s) in the skin has been elucidated by a detailed analysis of the products formed after ultraviolet light exposure. The photolytic product isolated from the skin of rats exposed to ultraviolet irradiation was identified as previtamin D 3 by several criteria including its characteristic ultraviolet absorption spectrum, mass spectrum, and thermal isomerization to vitamin D 3 , which itself was identified also by mass spectroscopy. Vitamin D 3 per se was not formed by ultraviolet irradiation-vitamin D 3 arises exclusively from the thermal conversion of previtamin D 3 . Detectable amounts of lumisterol 3 or tachysterol 3 were not seen

The oncogenic action of ionizing radiation on rat skin

International Nuclear Information System (INIS)

Burns, F.J.

1991-01-01

Progress has occurred in several areas corresponding to the specific aims of the proposal: (1) Progression and multiple events in radiation carcinogenesis of rat skin as a function of LET; (2) cell cycle kinetics of irradiated rat epidermis as determined by double labeling and double emulsion autoradiography; (3) oncogene activation detected by in situ hybridization in radiation-induced rat skin tumors; (4) amplification of the c-myc oncogene in radiation-induced rat skin tumors as a function of LET; and (5) transformation of rat skin keratinocytes by ionizing radiation in combination with c-Ki-ras and c-myc oncogenes. 111 refs., 13 figs., 12 tabs

Structural and functional changes in the intenstine of irradiated and hypothermic irradiated rats : a scanning and transmission electron microscopic study

International Nuclear Information System (INIS)

Chaudhuri, S.; Chaudhuri, Swapna; Roy, Bijon

1982-01-01

Severe destructive changes in the intestine of rats following whole body exposure to gamma rays (832 rads) were observed by light microscope, scanning and transmission electron microscope studies. Hypothermia (15deg C rectal temperature) induced prior to irradiation protected the intestinal mucosa from destruction. A simultaneous study showed that glucose absorption decreased significantly in irradiated rats, whereas it was increased in hypothermic irradiated animals. (author)

Effects of hyperbaric oxygen and irradiation on experimental skin flaps in rats

International Nuclear Information System (INIS)

Nemiroff, P.M.; Merwin, G.E.; Brant, T.; Cassisi, N.J.

1985-01-01

This study investigated the effects of hyperbaric oxygen (HBO) and irradiation (RT) on experimental skin flaps in rats under varying conditions. Animals were assigned at random to 1 of 15 groups that represented all possible ordering effects of HBO, RT, and flap, as well as controls that included flap-only, RT-only, and HBO-only groups. Cranially based skin flaps measuring 3 x 9 cm were elevated on the dorsum. The surviving length was evaluated with fluorescein dye 7 days after the operation. Depending on the treatment condition, HBO was given either 48 hours or 24 hours before flap elevation, or within 4 hours or 48 hours after flap elevation. Rats receiving RT ( 60 Co) were given a single dose of 1000 rads to the dorsum. Results showed that all groups receiving HBO within 4 hours after flap elevation had significantly greater flap survival length, with as much as a 22% greater length of surviving flap. HBO given 48 hours before flap elevation also significantly improved flap survival over controls. RT appeared to have no immediate significant effect on flap survival. However, rats receiving RT, regardless of other factors, gained significantly less weight than did controls. Findings clearly indicate that, to be effective, HBO needs to be given as soon after surgery as possible

An experimental study of the effect of total lymphoid irradiation on the survival of skin allografts

International Nuclear Information System (INIS)

Park, Charn Il; Han, Man Chung

1981-01-01

The study was undertaken to determine the effect of fractionated high-dose total lymphoid irradiation (TLI) on the survival of skin allograft despite major histocompatibility difference. Total lymphoid irradiation is a relatively safe form of radiotherapy, has been used extensively to treat lymphoid malignancies in humans with few side effects. A total of 90 rats, Sprague-Dawley rat as recipient and Wistar rat as donor, were used for the experiment, of which 10 rats were used to determine mixed lymphocyte response (MLR) for antigenic difference and skin allografts was performed in 30 rats given total lymphoid irradiation to assess the immunosuppressive effect of total lymphoid irradiation despite major histocompatibility difference. In addition, the peripheral white blood cell counts and the proportion of lymphocytes was studied in 10 rats given total lymphoid irradiation but no skin graft to determine the effects of bone marrow suppression. The results obtained are summarized as follows. 1. The optimum dose of total lymphoid irradiation was between 1800 rads to 2400 rads. 2. The survival of skin graft on rats given total lymphoid irradiation (23.2 ± 6.0 days) was prolonged about three folds as compared to unirradiated control (8.7 ± 1.3 days). 3. Total lymphoid irradiation resulted in a severe leukopenia with marked lymphopenia, but the count was normal by the end of 3rd week. 4. The study suggests that total lymphoid irradiation is a nonlethal procedure that could be used successfully in animals to transplant allograft across major histocompatibility barriers

An experimental study of the effect of total lymphoid irradiation on the survival of skin allografts

Energy Technology Data Exchange (ETDEWEB)

Park, Charn Il; Han, Man Chung [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

1981-06-15

The study was undertaken to determine the effect of fractionated high-dose total lymphoid irradiation (TLI) on the survival of skin allograft despite major histocompatibility difference. Total lymphoid irradiation is a relatively safe form of radiotherapy, has been used extensively to treat lymphoid malignancies in humans with few side effects. A total of 90 rats, Sprague-Dawley rat as recipient and Wistar rat as donor, were used for the experiment, of which 10 rats were used to determine mixed lymphocyte response (MLR) for antigenic difference and skin allografts was performed in 30 rats given total lymphoid irradiation to assess the immunosuppressive effect of total lymphoid irradiation despite major histocompatibility difference. In addition, the peripheral white blood cell counts and the proportion of lymphocytes was studied in 10 rats given total lymphoid irradiation but no skin graft to determine the effects of bone marrow suppression. The results obtained are summarized as follows. 1. The optimum dose of total lymphoid irradiation was between 1800 rads to 2400 rads. 2. The survival of skin graft on rats given total lymphoid irradiation (23.2 {+-} 6.0 days) was prolonged about three folds as compared to unirradiated control (8.7 {+-} 1.3 days). 3. Total lymphoid irradiation resulted in a severe leukopenia with marked lymphopenia, but the count was normal by the end of 3rd week. 4. The study suggests that total lymphoid irradiation is a nonlethal procedure that could be used successfully in animals to transplant allograft across major histocompatibility barriers.

A synthetic superoxide dismutase/catalase mimetic EUK-207 mitigates radiation dermatitis and promotes wound healing in irradiated rat skin.

Science.gov (United States)

Doctrow, Susan R; Lopez, Argelia; Schock, Ashley M; Duncan, Nathan E; Jourdan, Megan M; Olasz, Edit B; Moulder, John E; Fish, Brian L; Mäder, Marylou; Lazar, Jozef; Lazarova, Zelmira

2013-04-01

In the event of a radionuclear attack or nuclear accident, the skin would be the first barrier exposed to radiation, though skin injury can progress over days to years following exposure. Chronic oxidative stress has been implicated as being a potential contributor to the progression of delayed radiation-induced injury to skin and other organs. To examine the causative role of oxidative stress in delayed radiation-induced skin injury, including impaired wound healing, we tested a synthetic superoxide dismutase (SOD)/catalase mimetic, EUK-207, in a rat model of combined skin irradiation and wound injury. Administered systemically, beginning 48 hours after irradiation, EUK-207 mitigated radiation dermatitis, suppressed indicators of tissue oxidative stress, and enhanced wound healing. Evaluation of gene expression in irradiated skin at 30 days after exposure revealed a significant upregulation of several key genes involved in detoxication of reactive oxygen and nitrogen species. This gene expression pattern was primarily reversed by EUK-207 therapy. These results demonstrate that oxidative stress has a critical role in the progression of radiation-induced skin injury, and that the injury can be mitigated by appropriate antioxidant compounds administered 48 hours after exposure.

The dose penumbra of a custom-made shield used in hemibody skin electron irradiation.

Science.gov (United States)

Rivers, Charlotte I; AlDahlawi, Ismail; Wang, Iris Z; Singh, Anurag K; Podgorsak, Matthew B

2016-11-08

We report our technique for hemibody skin electron irradiation with a custom-made plywood shield. The technique is similar to our clinical total skin electron irradiation (TSEI), performed with a six-pair dual field (Stanford technique) at an extended source-to-skin distance (SSD) of 377 cm, with the addition of a plywood shield placed at 50 cm from the patient. The shield is made of three layers of stan-dard 5/8'' thick plywood (total thickness of 4.75 cm) that are clamped securely on an adjustable-height stand. Gafchromic EBT3 films were used in assessing the shield's transmission factor and the extent of the dose penumbra region for two different shield-phantom gaps. The shield transmission factor was found to be about 10%. The width of the penumbra (80%-to-20% dose falloff) was measured to be 12 cm for a 50 cm shield-phantom gap, and reduced slightly to 10 cm for a 35 cm shield-phantom gap. In vivo dosimetry of a real case confirmed the expected shielded area dose. © 2016 The Authors.

Expression of apoptosis-related genes in acute β-irradiated skin injury in rats

International Nuclear Information System (INIS)

Zhao Xiaoyu; He Hanliang; Qi Qiang; Lin Wei; Shen Guoliang

2012-01-01

Objective: To investigate the dynamic expression of apoptosis-related genes Bcl-2, Bax and P53 in acute radiation-induced skin ulcers, and to explore the underlying mechanism involved in retarded healing of the ulcer. Methods: Fifty-four female SD rats were divided into 3 groups. The model of acute radiation-induced skin injury, in rats was replicated with 45 Gy electron accelerator β-ray to the skin as radiation group (n=24); the model of deep second degree scald in rats was established as burn group (n=24); 6 normal rats were served as normal control group. From different periods skin wounds, the expression of Bcl-2, Bax and P53 were respectively assessed by means of immunohistochemical technique and. apoptosis was observed by TUNEL assay. Results: (1) The result of the TUNEL manifested that the integral absorbance (IA) of the radiation group was much higher than that of the control group. There is statistical significance between the two groups (P<0.05). (2) 0, 1, 2, 3 weeks after wound emerging, the Bax and P53 integral absorbance (IA) in radiation group was much higher than that of the control group. The Bcl-2 integral absorbance (IA) in bum group was much higher than that of the radiation group. There is statistical significance between the two groups (P<0.05). Conclusions: It was shown that apoptosis of β radiation manifested three typical characteristics, namely early occurrence, high frequency and delayed disappearance after radiation, which might explain the delayed wound healing caused by β radiation. (authors)

Effect of melatonin and time of administration on irradiation-induced damage to rat testes

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G. Take

2009-07-01

Full Text Available The effect of ionizing irradiation on testes and the protective effects of melatonin were investigated by immunohistochemical and electron microscopic methods. Eighty-two adult male Wistar rats were divided into 10 groups. The rats in the irradiated groups were exposed to a sublethal irradiation dose of 8 Gy, either to the total body or abdominopelvic region using a 60Co source at a focus of 80 cm away from the skin in the morning or evening together with vehicle (20% ethanol or melatonin administered 24 h before (10 mg/kg, immediately before (20 mg/kg and 24 h after irradiation (10 mg/kg, all ip. Caspace-3 immunoreactivity was increased in the irradiated group compared to control (P < 0.05. Melatonin-treated groups showed less apoptosis as indicated by a considerable decrease in caspace-3 immunoreactivity (P < 0.05. Electron microscopic examination showed that all spermatogenic cells, especially primary spermatocytes, displayed prominent degeneration in the groups submitted to total body and abdominopelvic irradiation. However, melatonin administration considerably inhibited these degenerative changes, especially in rats who received abdominopelvic irradiation. Total body and abdominopelvic irradiation induced identical apoptosis and testicular damage. Chronobiological assessment revealed that biologic rhythm does not alter the inductive effect of irradiation. These data indicate that melatonin protects against total body and abdominopelvic irradiation. Melatonin was more effective in the evening abdominopelvic irradiation and melatonin-treated group than in the total body irradiation and melatonin-treated group.

Comparison of three techniques for skin total irradiation with electrons

International Nuclear Information System (INIS)

Batista, Delano V.S.; Bardella, Lucia H.; Rosa, Luiz A.R. da

2011-01-01

This paper compared three techniques of skin total irradiation with electrons: 1) horizontal positioning, 2) vertical positioning - rotatory technique and 3) vertical positioning - six fields technique. For that, a anthropomorphic phantom was positioned according to the recommendation for each technique and was i radiated at the linear accelerator by using the 6 MeV electrons. Radiochromic films were positioned on the surface in various regions of the phantom for measurement of absorbed dose. A ionization chamber was positioned inside of equivalent issue plates for dose evaluation due to the photons produced by electron stopping. The technique 2 and 3 have shown too similar in the results and number or discrepant points (8 and 10 respectively) of prescription lower than the technique 1 (22 points). The total body dose of photons of the 1, 2 and 3 techniques was 2.2%, 5.3% and 5.2% respectively

Electron microscopic study of the spilt irradiation effects on the rat parotid ductal cells

International Nuclear Information System (INIS)

Kim, Sung Soo; Lee, Sang Rae

1988-01-01

This study was designed to investigate the effects of split irradiation on the salivary ductal cells, especially on the intercalated cells of the rat parotid glands. For this study, 24 Sprague-Dawley strain rats were irradiated on the head and neck region with two equal split doses of 9 Gy for a 4 hours interval by Co-60 teletherapy unit, Picker's mode l 4M 60. The conditions of irradiation were that field size, dose rate, SSD and depth were 12 X 5 cm, 222 cGy/min, 50 cm and 1 cm, respectively. The experimental animals were sacrificed 1, 2, 3, 6, 12, hours and 1, 3, 7, days after the irradiation and the changes of the irradiated intercalated cells of the parotid glands were examined under light and electron microscope. The results were as follows: 1. By the split irradiation, the degenerative changes of intercalated cells of the parotid glands appeared at 3 hours after irradiation and the most severe cellular degeneration observed at 6 hours after irradiation. The repair processes began from 12 hours after irradiation and have matured progressively. 2. Under electron microscope, loss of nuclear membrane, microvilli and secretory granules, derangement of chromosomes, degeneration of cytoplasm, atrophy or reduction of intracytoplasmic organelles were observed in the intercalated ductal cells after split irradiation. 3. Under light microscope, derangement of ductal cells, widening of cytoplasms and nuclei, hyperchromatism and proliferation of ductal cells were observed in intercalated ducts after split irradiation.

The oncogenic action of ionizing radiation on rat skin

International Nuclear Information System (INIS)

Burns, F.J.; Garte, S.J.

1990-01-01

An extensive experiment involving approximately 400 rats exposed to the neon ion beam at the Bevalac in Berkeley, CA and to electrons is nearing completion. Progress is described in three areas corresponding to the specific aims of the proposal: (1) carcinogenesis and DNA strand breaks in rat skin following exposure by the neon ions or electrons; (2) oncogene activation in radiation-induced rat skin cancers; (3) DNA strand breaks in the epidermis as a function of radiation penetration. 59 refs., 4 tabs

Application of photo-magnetic therapy for treatment of skin radiation damage in rats.

Science.gov (United States)

Simonova-Pushkar, L I; Gertman, V Z; Bilogurova, L V

2014-09-01

To improve methods of prevention and treatment of local radiation injury to the skin using the photomagnetic therapy. Materials and methods. Study was conducted on 60 male Wistar rats with 180-200 g bodyweight. The femoral area right hind limb of rats was locally irradiated by X-ray unit at a dose of 80.0 Gy. Exposed animals were divided into 2 groups: control and experimental. The rats of the experimental group received 2 courses of photo-magnetic therapy on the irradiated skin. The observations were carried out for 60 days. Methods - clinical, histological and statistical. Results. Local irradiation of rat skin causes the development of radiation ulcers in 60-70 % of the animals with the destruction of the structure in all layers of the skin. Spontaneous healing of radiation ulcer lasts at least two months with no complete skin recovery. Photo-magnetic therapy applied immediately after irradiation resulted in two-folddecrease of frequency of radiation ulcer incidence, accelerated the complete healing for 3 weeks and to ameliorated their progress. Histological examination showed that the photo-magnetic therapy reduced the extent of damage to all layers of the skin with restoration of epidermis and dermis structure and reduced the degree of inflammatory and destructive processes in the dermis. Conclusions. Photo-magnetic therapy produces a significant positive treatment effect by significantly reducing the inflammatory and destructive processes in all layers of the skin, stimulates the blood flow recovery in damaged tissue both with fibroblast proliferation and synthesis activation of native collagen fibers and other components of connective tissue, so almost a month accelerates ulcer healing radiation. L. I. Simonova-Pushkar, V. Z. Gertman, L. V. Bilogurova.

Antioxidant effects of an ozonized theobroma oil formulation on damaged-inflammatory rat skin

Energy Technology Data Exchange (ETDEWEB)

Sanchez, Y.; Diaz, M.F.; Hernandez, F.; Gila, D.; Ga, G.

2011-07-01

The aim of this study was to determine whether a cosmetic formulation elaborated with ozonized theobroma oil may exert beneficial effects in the restoring of the antioxidant activity on the skin of rats previously irradiated with ultraviolet light. 0.5 g of the formulation was applied on the skin of rats for five days. Superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) activity were determined in a homogenate of rat skin. Malondialdehyde (MDA), conjugated dienes (CD) and total hydroperoxide (THP) content were determined as biomarkers of oxidative stress. Using these parameters, antioxidant and oxidant activity, redox index and oxidative stress grade were determined. The total antioxidant activity was significantly increased while the redox index, total oxidant activity and oxidative stress grade decreased significantly in damaged rats treated with the formulation. These results show the antioxidant properties of the cosmetic formulation due to the stimulation of antioxidant enzymes such as SOD and GPx, preventing skin injury induced by ultraviolet irradiation. (Author).

An electron microscopic study on the effects of irradiation on the acinar cells of rat parotid gland

Energy Technology Data Exchange (ETDEWEB)

Ko, Kwang Jun; Lee, Sang Rae [Dept. of Oral Radiology, College of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

1988-11-15

The author studies the histopathologic changes according to a single or a split does and the time after irradiation on the acinar cells of rat parotid gland. 99 Sprague Dawley rats, weighing about 120 gm, were divided into control and 3 experimental groups. In experimental groups, Group I and II were delivered a single does of 15 Gy, 18 Gy and Group III and IV were delivered two equal split doses of 9 Gy, 10.5 Gy for a 4 hours interval, respectively. The experimental groups were delivered by a cobalt-60 teletherapy unit with a dose rate of 222 cGy/min, source-skin di stance of 50 cm, depth of 1 cm and a field size of 12 X 5 cm. The animals were sacrificed at 1, 2, 3, 6, 12 hours, 1, 3, 7 days after irradiation and examined by light and electro n microscopy. The results were as follows: 1. As the radiation dose increased and acinar cells delivered a single dose exposure were more damaged, and the change of acinar cells appeared faster than those of a split does exposure. 2. The histopathologic change of acinar cells appeared at 1 hour after irradiation. The recovery from damaged acinar cells appeared at 1 day after irradiation and there was a tendency that the recovery from damage of a split dose exposure was somewhat later than of a single dose exposure. 3. Light microscope showed atrophic change of acinar cells and nucleus, degeneration and vesicle formation of cytoplasm, widening of intercellular space and interlobular space. 4. Electron microscope showed loss of nuclear membrane, degeneration of nucleus and nucleoli, clumping of cytoplasm, widening and degeneration of rough endoplasmic reticulum, loss of cristae of mitochondria, lysosome, autophagosome and lipid droplet. 5. Electron microscopically, the change of rough endoplasmic reticulum was most prominent and this appeared at 1 hour after irradiation as early changes of acinar cells. The nuclear change appeared at 2 hours after irradiation and the loss of cristae of mitochondria was observed at 2 hours after

An electron microscopic study on the effects of irradiation on the acinar cells of rat parotid gland

International Nuclear Information System (INIS)

Ko, Kwang Jun; Lee, Sang Rae

1988-01-01

The author studies the histopathologic changes according to a single or a split does and the time after irradiation on the acinar cells of rat parotid gland. 99 Sprague Dawley rats, weighing about 120 gm, were divided into control and 3 experimental groups. In experimental groups, Group I and II were delivered a single does of 15 Gy, 18 Gy and Group III and IV were delivered two equal split doses of 9 Gy, 10.5 Gy for a 4 hours interval, respectively. The experimental groups were delivered by a cobalt-60 teletherapy unit with a dose rate of 222 cGy/min, source-skin di stance of 50 cm, depth of 1 cm and a field size of 12 X 5 cm. The animals were sacrificed at 1, 2, 3, 6, 12 hours, 1, 3, 7 days after irradiation and examined by light and electro n microscopy. The results were as follows: 1. As the radiation dose increased and acinar cells delivered a single dose exposure were more damaged, and the change of acinar cells appeared faster than those of a split does exposure. 2. The histopathologic change of acinar cells appeared at 1 hour after irradiation. The recovery from damaged acinar cells appeared at 1 day after irradiation and there was a tendency that the recovery from damage of a split dose exposure was somewhat later than of a single dose exposure. 3. Light microscope showed atrophic change of acinar cells and nucleus, degeneration and vesicle formation of cytoplasm, widening of intercellular space and interlobular space. 4. Electron microscope showed loss of nuclear membrane, degeneration of nucleus and nucleoli, clumping of cytoplasm, widening and degeneration of rough endoplasmic reticulum, loss of cristae of mitochondria, lysosome, autophagosome and lipid droplet. 5. Electron microscopically, the change of rough endoplasmic reticulum was most prominent and this appeared at 1 hour after irradiation as early changes of acinar cells. The nuclear change appeared at 2 hours after irradiation and the loss of cristae of mitochondria was observed at 2 hours after

Radioprotective effect of c-ski on rat skin fibroblast in vitro

International Nuclear Information System (INIS)

Liu Xia; Li Ping; Zhang En; Liu Ping; Zhou Ping; Zhou Yuanguo

2006-01-01

Objective: To examine radioprotective effect of c-ski on rat skin fibroblast in vitro and explore its possible mechanism. Methods: The effect of soft X-ray irradiation at dose varied from 2 to 8 Gy on cell apoptosis in rat skin fibroblast were determined by flow cytometry with Annexin-V-FITC-PI labelling. The effect of c-ski gene transfection on cell apoptosis was evaluated after soft X-ray irradiation of 4 Gy. The protein expressions of Bax and Bcl-2 after c-ski gene transfection were measured with the Western blot method. Results: Soft X-ray irradiation increases cell apoptosis, and the increase is proportional to the irradiation dose. Apoptosis ratio increases with time since the irradiation, and reaches its peak at 36h after the irradiation, c-ski gene was observed to markedly decrease apoptosis index at 24 h after soft X-ray irradiation of 4 Gy compared to the control group, significant increase of the protein expression of Bcl-2 was observed. C-ski gene was found no significant effect on the protein expression of Bax. Conclusion: c-ski gene can decrease radiation sensitivity of skin fibroblast, promoting Bcl-2 protein expression is one of its possible mechanism for this radioprotective effects. (authors)

Comparison of the incidence and time patterns of radiation-induced skin cancer in humans and rats

International Nuclear Information System (INIS)

Albert, R.E.; Burns, F.J.; Shore, R.

1978-01-01

Cancer induction in rat skin and human skin are compared following exposure to X-rays. The human data were obtained by follow-up of 2213 children irradiated between 1940 and 1959 for tinea capitis (ringworm) of the scalp. The scalp was irradiated at one session using five fields of 100 kVp X-rays. The scalp dose ranged from 500-800 rads. The rats were irradiated on their dorsal skin with a 1100-rad dose of 30 kVp X-rays. The tumours were predominantly basal cell carcinomas in both species. The proportion of people with tumours as a function of elapsed time since exposure was consistent with a power function with an exponent of 5.4, and had reached 3% or 0.08 tumours per person in most recent survey (35 years after exposure). Of the 64 tumours observed in human skin, a substantial proportion was on the directly irradiated skin just outside the hair-covered regions of the scalp. So far there are no tumours among the 530 irradiated nonwhites in the study when about eight cases would be expected in a comparable group of irradiated whites. Only four skin tumours have been observed in 1396 control patients. The temporal curve of radiation-induced tumours for human skin could be approximately superimposed on that for rats by contracting the time scale by a factor of 37.1. The temporal response of the two species is approximately proportional to their median life spans. (author)

The abdominal skin of female Sprague-Dawley rats is more sensitive than the back skin to drug-induced phototoxicity.

Science.gov (United States)

Kuga, Kazuhiro; Yasuno, Hironobu; Sakai, Yumi; Harada, Yumiko; Shimizu, Fumi; Miyamoto, Yumiko; Takamatsu, Yuki; Miyamoto, Makoto; Sato, Keiichiro

2017-11-01

In vivo phototoxicity studies are important to predict drug-induced phototoxicity in humans; however, a standard methodology has not established. To determine differences in sensitivity to drug-induced phototoxicity among various skin sites, we evaluated phototoxic reactions in the back and abdominal skin of female Sprague-Dawley rats orally dosed with phototoxic drugs (pirfenidone, 8-methoxysoraren, doxycycline, and lomefloxacin) or a non-phototoxic drug (gatifloxacin) followed by solar-simulated light irradiation comprising 18J/cm 2 ultraviolet A. Tissue reactions were evaluated by macroscopic and microscopic examination and immunohistochemistry for γ-H2AX, and tissue concentrations of pirfenidone, doxycycline, and lomefloxacin were measured by tandem mass spectrometry. In addition, the thicknesses of the skin layers at both sites were measured in drug-naïve rats. The abdominal skin showed more severe reactions to all phototoxic drugs than the back skin, whereas the minimal erythema dose in drug-naïve rats and skin concentrations of each drug were comparable between the sites. Furthermore, histopathological lesions and γ-H2AX-positive cells in the abdominal skin were detected in deeper layers than in the back skin. The stratum corneum and dermis in the abdominal skin were significantly thinner than in the back skin, indicating a difference in the depth of light penetration and potentially contributing to the site differences observed in sensitivity to phototoxicity. Gatifloxacin did not induce any phototoxic reactions at either site. In conclusion, the abdominal skin is more sensitive to drug-induced phototoxicity than the back skin and may represent a preferable site for irradiation in this rat phototoxicity model. Copyright © 2017 Elsevier Inc. All rights reserved.

Histopathological changes induced by Electromagnetic Radiation on Rat changes induced by Electromagnetic Radiation on Rat Skin before and after Silymarin and Vitamin E treatment

International Nuclear Information System (INIS)

Ibrahim, N.F.; Elkady, A.

2013-01-01

People in industrial and developing countries are exposed to large variety of environmental influencing agents including chemical, air, water and food pollution. Also physical harmful agents such as ultraviolet radiation, and electromagnetic radiation especially by cell phones. Our aim in this study was to investigate the effect of electromagnetic radiation on the skin of male albino rats and the role of silymarin and Vitamin E as skin protectors. The male rats were grouped into 8 groups :1-Control group, 2-Irradiated group, groups 3,4,5 are irradiated with silymarin administration, irradiated with Vitamin E administration, irradiated with silymarin and Vitamin E administration groups respectively. The remaining three groups (6, 7, 8) served as healthy control with antioxidants administration. Paraffin sections stained with Hematoxylin and Eosin stain was used for showing microscopic changes. Following irradiation, the results showed dystrophic changes in the skin represented by atrophy of epidermal layers with absence of stratum corneum and epidermal vesicles formation. Collagen fibres were disorganized and appeared more eosinophilic and homogenous. Loss of skin appendages, lysis of collagen and edematous tissues were also observed in the dermal layer. Following administration of silymarin and Vitamin E the results showed improvement of the skin texture, while edema was still observed. conclusion: Treatment by silymarin alone or Vitamin E alone did not restore the damaging effect of electromagnetic radiation on rat skin. But when both antioxidants were given following radiation-exposure there were marked improvements on morphological structure of rat skin. These results indicate the importance of both silymarin and Vitamin E as protectors from the harmful effect of electromagnetic radiation on skin.

Effect of irradiation on glycosaminoglycans connect in rat tissue

Energy Technology Data Exchange (ETDEWEB)

Drozdz, M; Kucharz, E; Glowacki, A; Zylka, J

1981-01-01

Glycosaminoglycan (GAGs) fractions were determined in tissues (skin, liver, lungs, aortic wall) and blood serum of rats irradiated with a single dose of 500 R. An increase of total GAGs as well as changes in the fractions were found in the tissues and urine of exposed rats.

Evaluation of morphological changes of the skin after radiation-induced injury in Wistar rats

International Nuclear Information System (INIS)

Andrade, Cherley Borba Vieira de

2010-01-01

The cancer covers a heterogeneous group of more than 100 diseases with different etiology and prognosis. Radiotherapy is one of the most commonly used treatment modalities, aiming at the destruction of cancer cells, using ionizing radiation. One of the limiting factors of radiotherapy is that radiation promotes the death of tumor cells in addition to injure healthy tissue neighboring the tumor, and may cause their death. Irradiation of the skin, accidental or for therapeutic purposes can trigger many injuries culminating in fibrosis, which implies functional alteration of the body. The evaluation of morphological effects associated with skin irradiation becomes essential to develop more effective radiation strategies and decreased morbidity; and in case of accidents, proper handling of the victim.Evaluate radio-induced dermal changes using a Wistar rats model irradiated with 10, 40 and 60Gy. Male Wistar rats, aged approximately three months, were pre-anesthetized with midazolam and xylazine and anesthetized with sodium pentobarbital, shaved in the back, immobilized on polystyrene support in the prone position and irradiated with doses of 10, 40 and 60 Gy, with 4MeV nominal energy electron beams. The skin was irradiated in a 3cm 2 field, and used 0.5cm of tissue equivalent material, to obtain a homogeneous dose distribution. After irradiation, the animals remained on constant evaluation, and the lesions were recorded photographically. The animals were divided into groups and were killed on the irradiation day, 5, 10, 15, 25 and 100 days after irradiation. The skin was fixed in 10% formaldehyde; the samples were embedded in paraffin and cut. The sections were stained with hematoxylin-eosin, picrosirius red and immuno stained with antibody anti-TGF beta1. Another part of the tissue was fixed in 2.5% glutaraldehyde and processed for scanning electron microscopy. It was observed macroscopically the appearance of skin lesions similar to burns on the entire irradiated

Air-electron stream interactions during magnetic resonance IGRT. Skin irradiation outside the treatment field during accelerated partial breast irradiation

International Nuclear Information System (INIS)

Park, Jong Min; Shin, Kyung Hwan; Wu, Hong-Gyun; Kim, Jung-in; Park, So-Yeon; Kim, Jin Ho; Jeon, Seung Hyuck; Choi, Noorie

2018-01-01

To investigate and to prevent irradiation outside the treatment field caused by an electron stream in the air generated by the magnetic field during magnetic resonance image-guided accelerated partial breast irradiation (APBI). In all, 20 patients who received APBI with a magnetic resonance image-guided radiation therapy (MR-IGRT) system were prospectively studied. The prescription dose was 38.5 Gy in 10 fractions of 3.85 Gy and delivered with a tri-cobalt system (the ViewRay system). For each patient, primary plans were delivered for the first five fractions and modified plans with different gantry angles from those of the primary plan (in-treatment plans) were delivered for the remaining five fractions to reduce the skin dose. A 1 cm thick bolus was placed in front of the patient's jaw, ipsilateral shoulder, and arm to shield them from the electron stream. Radiochromic EBT3 films were attached to the front (towards the breast) and back (towards the head) of the bolus during treatment. Correlations between the measured values and the tumor locations, treatment times, and tumor sizes were investigated. For a single fraction delivery, the average areas of the measured isodoses of 14% (0.54 Gy), 12% (0.46 Gy), and 10% (0.39 Gy) at the front of the boluses were as large as 3, 10.4, and 21.4 cm 2 , respectively, whereas no significant dose could be measured at the back of the boluses. Statistically significant but weak correlations were observed between the measured values and the treatment times. During radiotherapy for breast cancer with an MR-IGRT system, the patient must be shielded from electron streams in the air generated by the interaction of the magnetic field with the beams of the three-cobalt treatment unit to avoid unwanted irradiation of the skin outside the treatment field. (orig.) [de

Effect of heme oxygenase-1 on radiation-induced skin injury

International Nuclear Information System (INIS)

Song Chuanjun; Meng Xingjun; Xie Ling; Chen Qing; Zhou Jundong; Zhang Shuyu; Wu Jinchang

2012-01-01

Objective: To investigate the effect of heme oxygenase-1 (HO-1) on the acute radiation-induced skin injury by gene transfer. Methods: Thirty-three male SD rats were randomly divided into three groups as PBS-injected group, Ad-EGFP-injected group and Ad-HO-1-injected group (n=11). In each group, three rats were used for determining the expression of target gene and the other rats were irradiated on the buttock skin with 40 Gy electron beam generated by a linear accelerator. Immediately after irradiation, rats were administered with a subcutaneous injection of PBS, Ad-EGFP or Ad-HO-1, respectively. Subsequently, the skin reactions were measured twice a week using the semi-quantitative skin injury scale. Results: The strong positive expression of HO-1 was observed in subcutaneous dermal tissue after injection of Ad-HO-1. Compared to the PBS-injected group or the Ad-EGFP-injected group, a significant mitigation of skin injury was observed in Ad-HO-1-injected mice 14 d after irradiation (q=0.000-0.030, P<0.05). Conclusions: HO-1 could significantly mitigate radiation-induced acute skin injury and Ad-HO-1 could be used to treat radiation-induced skin injury. (authors)

Evaluation by electronic paramagnetic resonance of the number of free radicals produced in irradiated rat bone

International Nuclear Information System (INIS)

Marble, G.; Valderas, R.

1966-01-01

The number of long half-life free radicals created by gamma irradiation in the bones of the rat has been determined from the electrons paramagnetic resonance spectrum. This number decreases slowly with time (calculated half life: 24 days). It is proportional to the dose of gamma radiation given to the rat. The method could find interesting applications in the field of biological dosimetry. (authors) [fr

Histological study of subcutaneous fat at NIR laser treatment of the rat skin in vivo

Science.gov (United States)

Yanina, I. Y.; Svenskaya, Yu. I.; Navolokin, N. A.; Matveeva, O. V.; Bucharskaya, A. B.; Maslyakova, G. N.; Gorin, D. A.; Sukhorukov, G. B.; Tuchin, V. V.

2015-07-01

The goal of this work is to quantify impact of in vivo photochemical treatment using indocyanine green (ICG) or encapsulated ICG and NIR laser irradiation through skin of rat with obesity by the follow up tissue sampling and histochemistry. After 1 hour elapsed since 1-min light exposure samples of rat skin with subcutaneous tissue of thickness of 1.5-2.5 mm were taken by surgery from rats within marked 4-zones of the skin site. For hematoxylin-eosin histological examination of excised tissue samples, fixation was carried out by 10%-formaldehyde solution. For ICG and encapsulated ICG subcutaneous injection and subsequent 1-min diode laser irradiation with power density of 8 W/cm2, different necrotic regions with lipolysis of subcutaneous fat were observed. The obtained data can be used for safe layer-by-layer laser treatment of obesity and cellulite.

Air-electron stream interactions during magnetic resonance IGRT : Skin irradiation outside the treatment field during accelerated partial breast irradiation.

Science.gov (United States)

Park, Jong Min; Shin, Kyung Hwan; Kim, Jung-In; Park, So-Yeon; Jeon, Seung Hyuck; Choi, Noorie; Kim, Jin Ho; Wu, Hong-Gyun

2018-01-01

To investigate and to prevent irradiation outside the treatment field caused by an electron stream in the air generated by the magnetic field during magnetic resonance image-guided accelerated partial breast irradiation (APBI). In all, 20 patients who received APBI with a magnetic resonance image-guided radiation therapy (MR-IGRT) system were prospectively studied. The prescription dose was 38.5 Gy in 10 fractions of 3.85 Gy and delivered with a tri-cobalt system (the ViewRay system). For each patient, primary plans were delivered for the first five fractions and modified plans with different gantry angles from those of the primary plan (in-treatment plans) were delivered for the remaining five fractions to reduce the skin dose. A 1 cm thick bolus was placed in front of the patient's jaw, ipsilateral shoulder, and arm to shield them from the electron stream. Radiochromic EBT3 films were attached to the front (towards the breast) and back (towards the head) of the bolus during treatment. Correlations between the measured values and the tumor locations, treatment times, and tumor sizes were investigated. For a single fraction delivery, the average areas of the measured isodoses of 14% (0.54 Gy), 12% (0.46 Gy), and 10% (0.39 Gy) at the front of the boluses were as large as 3, 10.4, and 21.4 cm 2 , respectively, whereas no significant dose could be measured at the back of the boluses. Statistically significant but weak correlations were observed between the measured values and the treatment times. During radiotherapy for breast cancer with an MR-IGRT system, the patient must be shielded from electron streams in the air generated by the interaction of the magnetic field with the beams of the three-cobalt treatment unit to avoid unwanted irradiation of the skin outside the treatment field.

A dielectric method for measuring early and late reactions in irradiated human skin

International Nuclear Information System (INIS)

Nuutinen, J.; Lahtinen, T.; Turunen, M.; Alanen, E.; Tenhunen, M.; Usenius, T.; Kolle, R.

1998-01-01

Background and purpose: To measure the dielectric constant of irradiated human skin in order to test the feasibility of the dielectric measurements in the quantitation of acute and late radiation reactions. Materials and methods: The dielectric constant of irradiated breast skin was measured at an electromagnetic frequency of 300 MHz in 21 patients during postmastectomy radiotherapy. The measurements were performed with an open-ended coaxial line reflection method. The irradiation technique consisted of an anterior photon field to the lymph nodes and a matched electron field to the chest wall using conventional fractionation of five fractions/week to 50 Gy. Fourteen out of the 21 patients were remeasured 2 years later and the skin was palpated for subcutaneous fibrosis. Results: At 5 weeks the dielectric constant had decreased by 31 and 39% for the investigated skin sites of the photon and electron fields, respectively. There was a statistically significant inverse correlation between the mean dielectric constant and the clinical score of erythema. An unexpected finding was a decrease of the dielectric constant of the contralateral healthy skin during radiotherapy. Two years later a statistically significant positive correlation was found between the dielectric constant at the irradiated skin sites and the clinical score of subcutaneous fibrosis. Conclusions: Dielectric measurements non-invasively yield quantitative information concerning radiation-induced skin reactions. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Chitosan Dermal Substitute and Chitosan Skin Substitute Contribute to Accelerated Full-Thickness Wound Healing in Irradiated Rats

Directory of Open Access Journals (Sweden)

Abu Bakar Mohd Hilmi

2013-01-01

Full Text Available Wounds with full-thickness skin loss are commonly managed by skin grafting. In the absence of a graft, reepithelialization is imperfect and leads to increased scar formation. Biomaterials can alter wound healing so that it produces more regenerative tissue and fewer scars. This current study use the new chitosan based biomaterial in full-thickness wound with impaired healing on rat model. Wounds were evaluated after being treated with a chitosan dermal substitute, a chitosan skin substitute, or duoderm CGF. Wounds treated with the chitosan skin substitute showed the most re-epithelialization (33.2 ± 2.8%, longest epithelial tongue (1.62 ± 0.13 mm, and shortest migratory tongue distance (7.11 ± 0.25 mm. The scar size of wounds treated with the chitosan dermal substitute (0.13 ± 0.02 cm and chitosan skin substitute (0.16 ± 0.05 cm were significantly decreased (P<0.05 compared with duoderm (0.45 ± 0.11 cm. Human leukocyte antigen (HLA expression on days 7, 14, and 21 revealed the presence of human hair follicle stem cells and fibroblasts that were incorporated into and surviving in the irradiated wound. We have proven that a chitosan dermal substitute and chitosan skin substitute are suitable for wound healing in full-thickness wounds that are impaired due to radiation.

Progressive damage to rat skin induced by protons

International Nuclear Information System (INIS)

Molinari, Beatriz L.; Saint-Martin, Maria L.G.; Bernaola, Omar A.; Duran, Hebe; Policastro, Lucia L.; O'Connor, Silvia E.; Palmieri, Monica; Davidson, Miguel; Davidson, Jorge

2003-01-01

Wistar rats were locally irradiated with proton beams. Dorsal portions of the skin were irradiated to a dose of 20 Gy employing a plastic wedge as a variable thickness energy degrader. The animals were sacrificed 2,5,6,7,and 9 days post-irradiation. The doses were monitored with a transmission camera. Solid track detectors (Makrofold E) were placed on the area to be irradiated to determine spatial correlation with the dose. Tissue reactions were clearly observed and were quantitatively assessed as a function of dose. Track detectors proved to be valuable to determine the correlation between the dose and tissue damage . This biological experimental model proved useful to analyze the response of tissues to a gradient of doses yielded by a proton beam. (author)

Acceleration of skin wound healing by low-dose indirect ionizing radiation in male rats.

Science.gov (United States)

Jabbari, Nasrollah; Farjah, Gholam Hossein; Ghadimi, Behnam; Zanjani, Hajar; Heshmatian, Behnam

2017-08-01

A recent hypothesis has revealed that low-dose irradiation (LDI) with ionizing radiation might have a promoting effect on fracture healing. The aim of this study was to investigate the influence of direct (electron beam) and indirect (gamma-ray) low-dose ionizing irradiations on the wound healing process in male rats. In 72 male rats, a full-thickness wound was incised. The animals were randomly assigned to three groups, each with 24 rats. The first two groups were named IG-I and IG-II and respectively exposed to electron and gamma-radiations (75 cGy) immediately after the surgical procedure. The third group was considered as the control (CG) and remained untreated. Skin biopsies from the subgroups were collected on days 3, 7, 15, and 21 after the operation and evaluated using histological and biomechanical methods. Data were analyzed by one-way ANOVA, followed by Tukey's post hoc test using SPSS 20 software. Histological studies of tissues showed that the mean number of fibroblasts, macrophages, blood vessel sections, and neutrophils on the third and seventh days after the surgery in the gamma-treated group was higher than that in both other groups. In contrast, on day 21, the mean number of mentioned cells in the gamma-treated group was lower than in the other two groups. In addition, the mean maximum stress value was significantly greater in the gamma-treated group. Results of this study showed that gamma-ray irradiation is effective in the acceleration of wound healing. Copyright © 2017. Published by Elsevier Taiwan.

Acceleration of skin wound healing by low-dose indirect ionizing radiation in male rats

Directory of Open Access Journals (Sweden)

Nasrollah Jabbari

2017-08-01

Full Text Available A recent hypothesis has revealed that low-dose irradiation (LDI with ionizing radiation might have a promoting effect on fracture healing. The aim of this study was to investigate the influence of direct (electron beam and indirect (gamma-ray low-dose ionizing irradiations on the wound healing process in male rats. In 72 male rats, a full-thickness wound was incised. The animals were randomly assigned to three groups, each with 24 rats. The first two groups were named IG–I and IG–II and respectively exposed to electron and gamma-radiations (75 cGy immediately after the surgical procedure. The third group was considered as the control (CG and remained untreated. Skin biopsies from the subgroups were collected on days 3, 7, 15, and 21 after the operation and evaluated using histological and biomechanical methods. Data were analyzed by one-way ANOVA, followed by Tukey's post hoc test using SPSS 20 software. Histological studies of tissues showed that the mean number of fibroblasts, macrophages, blood vessel sections, and neutrophils on the third and seventh days after the surgery in the gamma-treated group was higher than that in both other groups. In contrast, on day 21, the mean number of mentioned cells in the gamma-treated group was lower than in the other two groups. In addition, the mean maximum stress value was significantly greater in the gamma-treated group. Results of this study showed that gamma-ray irradiation is effective in the acceleration of wound healing.

Evaluation by electronic paramagnetic resonance of the number of free radicals produced in irradiated rat bone; Evaluation par resonance paramagnetique electronique du nombre de radicaux libres produits dans l'os de rat irradie

Energy Technology Data Exchange (ETDEWEB)

Marble, G; Valderas, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1966-07-01

The number of long half-life free radicals created by gamma irradiation in the bones of the rat has been determined from the electrons paramagnetic resonance spectrum. This number decreases slowly with time (calculated half life: 24 days). It is proportional to the dose of gamma radiation given to the rat. The method could find interesting applications in the field of biological dosimetry. (authors) [French] Le nombre de radicaux libres a vie longue crees par irradiation gamma dans l'os de rat a ete determine a partir du spectre de resonance paramagnetique electronique. Ce nombre decroit lentement avec le temps (demi-vie calculee {approx_equal} 24 jours). IL est proportionnel a la dose de rayonnement gamma delivree au rat. La methode pourra trouver en dosimetrie biologique des applications interessantes. (auteurs)

Use of an electron reflector to improve dose uniformity at the vertex during total skin electron therapy

International Nuclear Information System (INIS)

Peters, V.G.

2000-01-01

Purpose: The vertex of the scalp is always tangentially irradiated during total skin electron therapy (TSET). This study was conducted to determine the dose distribution at the vertex for a commonly used irradiation technique and to evaluate the use of an electron reflector, positioned above the head, as a means of improving the dose uniformity. Methods and Materials: Phantoms, simulating the head of a patient, were irradiated using our standard procedure for TSET. The technique is a six-field irradiation using dual angled electron beams at a treatment distance of 3.6 meters. Vertex dosimetry was performed using ionization methods and film. Measurements were made for an unmodified 6 MeV electron beam and for a 4 MeV beam obtained by placing an acrylic scattering plate in the beam line. Studies were performed to examine the effect of electron scattering on vertex dose when a lead reflector, 50 x 50 cm in area, was positioned above the phantom. Results: The surface dose at the vertex, in the absence of the reflector, was found to be less than 40% of the prescribed skin dose. Use of the lead reflector increased this value to 73% for the 6 MeV beam and 99% for the degraded 4 MeV beam. Significant improvements in depth dose were also observed. The dose enhancement is not strongly dependent on reflector distance or angulation since the reflector acts as a large source of broadly scattered electrons. Conclusion: The vertex may be significantly underdosed using standard techniques for total skin electron therapy. Use of an electron reflector improves the dose uniformity at the vertex and may reduce or eliminate the need for supplemental irradiation

Evaluation by electronic paramagnetic resonance of the number of free radicals produced in irradiated rat bone; Evaluation par resonance paramagnetique electronique du nombre de radicaux libres produits dans l'os de rat irradie

Energy Technology Data Exchange (ETDEWEB)

Marble, G.; Valderas, R. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1966-07-01

The number of long half-life free radicals created by gamma irradiation in the bones of the rat has been determined from the electrons paramagnetic resonance spectrum. This number decreases slowly with time (calculated half life: 24 days). It is proportional to the dose of gamma radiation given to the rat. The method could find interesting applications in the field of biological dosimetry. (authors) [French] Le nombre de radicaux libres a vie longue crees par irradiation gamma dans l'os de rat a ete determine a partir du spectre de resonance paramagnetique electronique. Ce nombre decroit lentement avec le temps (demi-vie calculee {approx_equal} 24 jours). IL est proportionnel a la dose de rayonnement gamma delivree au rat. La methode pourra trouver en dosimetrie biologique des applications interessantes. (auteurs)

Tumor-associated proteins in rat submandibular gland induced by DMBA and irradiation

International Nuclear Information System (INIS)

Oh, Sung Ook; Choi, Soon Chul; Park, Tae Won; You, Dong Soo

1997-01-01

This study was performed in order to identify changes of the plasma membrane proteins in rat submandibular gland tumors induced by 7,12-dimethylbenz[a]anthracene [DMBA] and X-irradiation. Two kinds of tumor associated membrane proteins (protein A and B) were isolated with 3 M KCl extraction from rat submandibular gland tumors induced by DMBA and X-irradiation. To identify their antigenicities, immunoelectrophoresis and double immunodiffusion was carried out with various proteins extracted from liver, heart, skin and pancreas of adult rats and from embryonic liver, heart and skin. The rabbit antisera against the protein A did not cross-react with any of the proteins extracted from the above mentioned tissues, suggesting that protein A might be tumor specific antigen. However, the rabbit antisera against protein B was precipitated with proteins extracted from the liver of adult and embryonic rats. Polyacrylamide gel electrophoresis of these two proteins (A and B) showed that protein A was a dimer with molecular weights of 69,000 and 35,000 dalton, whereas protein B was a monomer with molecular weight of 50,000 dalton.

Quantitative measurements of oxidative stress in mouse skin induced by X-ray irradiation

International Nuclear Information System (INIS)

Chi, Cuiping; Tanaka, Ryoko; Okuda, Yohei; Ikota, Nobuo; Ozawa, Toshihiko; Anzai, Kazunori; Yamamoto, Haruhiko; Urano, Shiro

2005-01-01

To find efficient methods to evaluate oxidative stress in mouse skin caused by X-ray irradiation, several markers and methodologies were examined. Hairless mice were irradiated with 50 Gy X-rays and skin homogenates or skin strips were prepared. Lipid peroxidation was measured using the skin homogenate as the level of thiobarbituric acid reactive substances. The level of lipid peroxidation increased with time after irradiation and was twice that of the control at 78 h. Electron spin resonance (ESR) spectra of skin strips showed a clear signal for the ascorbyl radical, which increased with time after irradiation in a manner similar to that of lipid peroxidation. To measure levels of glutathione (GSH) and its oxidized forms (GSSG) simultaneously, two high performance liquid chromatography (HPLC) methods, sample derivatization with 1-fluoro-2,4-dinitrobenzene and detection with a UV detector (method A) and no derivatization and detection with an electrochemical detector (method B), were compared and the latter was found to be better. No significant change was observed within 24 h after irradiation in the levels of GSH and GSSG measured by method B. The GSH/GSSG ratio may be a less sensitive parameter for the evaluation of acute oxidative stress caused by X-ray irradiation in the skin. Monitoring the ascorbyl radical seems to be a good way to evaluate oxidative stress in skin in vivo. (author)

Treatment of skin damage due to irradiation and post-irradiation skin tumours, at the Hornheide special clinic

International Nuclear Information System (INIS)

Drepper, H.

1987-01-01

A short precis of 54 years of history of the Hornheide special clinic for tumours, tuberculosis, and plastic surgery of face and skin is followed by a description of the current tasks of the clinic as an interdisciplinary center for plastic surgery and rehabilitation with facilities for tumour surgery, radiotherapy, skin and tissue pathology, and psychotherapy. Important special areas of this interdisciplinary cooperation are the treatment of skin disorders due to radiation and of tumours on irradiated skin, as well as treatment and plastic surgery after removal of tumours by irradiation in order to make the affected areas fit for renewed irradiation. (TRV) [de

The oncogenic action of ionizing radiation on rat skin: Progress report, February 1, 1987-January 31, 1988

International Nuclear Information System (INIS)

Burns, F.J.

1987-01-01

The work outlined in this report includes: epidermal DNA strand breaks and radiation penetration; activation of oncogenes in radiation induced rat skin tumors; and rat skin carcinogenesis by neon ions. The effect of radiation penetration on DNA single strand breaks has been studied extensively in rat and mouse epidermis. The results show clearly that the number of strand breaks per unit dose in the epidermal DNA is reduced by 50% to 65% when the radiation penetration is reduced from 1.0 mm to 0.2 mm. This penetration effect on DNA strand breaks was not seen in mouse epidermal cell lines growing in plastic dishes. The results imply that DNA strand breakage in superficial cells is partially dependent on the radiation dose to underlying tissue. The phenomenon is not mediated by systemic interactions as it was observed in irradiated explanted skin. The oncogene activation pattern in the radiation-induced skin tumors was found to be tumor dependent. Either K-ras activation or c-myc amplification or both was observed in each tumor analyzed so far. Even benign fibromas exhibited c-myc amplification. The carcinogenicity of high penetration electrons (2.0 MeV) was determined in preparation for similar studies with a neon ion beam at the Berkeley Bevelac. The principal finding so far is a large excess of connective tissue tumors, fibromas (benign) and sarcomas (malignant). 59 refs., 1 tab

Acute skin reactions observed in fractionated proton irradiation

International Nuclear Information System (INIS)

Arimoto, Takuro; Maruhashi, Noboru; Takada, Yoshihisa; Hayakawa, Yoshinori; Inada, Tetsuo; Kitagawa, Toshio

1989-01-01

Between May 1985 and July 1987, 49 skin reactions of 43 patients treated by proton irradiation were observed at the Particle Radiation Medical Science Center (PARMS), the University of Tsukuba. Taking the peak skin score as an endpoint, the radiobiological effects [relative biological effectiveness (RBE) and time-dose relationship] of the proton beam in multi-fractionated treatments were estimated. Factors influencing the skin dose, such as the prescribed tumor dose, tumor site, and number of applied fields, were also analyzed. The following conclusions regarding acute skin reactions to the clinical use of proton irradiation were obtained: 1) the physical skin-sparing effect of proton irradiation in single-field irradiation, especially in superficial regions, is not large compared with that of high-energy photon irradiation; 2) multidirectional proton irradiation significantly reduced the skin dose and severity of acute reasons; 3) the radiobiological effects of the proton beam, RBE and the time factor, estimated in human skin in multi-fractional treatment were slightly smaller than those of X-rays, i.e., 0.92 and -0.25±0.09, respectively. (author)

Topical treatment of oral cavity and wounded skin with a new disinfection system utilizing photolysis of hydrogen peroxide in rats.

Science.gov (United States)

Yamada, Yasutomo; Mokudai, Takayuki; Nakamura, Keisuke; Hayashi, Eisei; Kawana, Yoshiko; Kanno, Taro; Sasaki, Keiichi; Niwano, Yoshimi

2012-01-01

The present study aimed to evaluate the acute locally injurious property of hydroxyl radical generation system by photolysis of H(2)O(2), which is a new disinfection system for the treatment of periodontitis developed in our laboratory. Firstly, generation of the hydroxyl radical by a test device utilizing the photolysis of H(2)O(2) was confirmed by applying an electron spin resonance (ESR)-spin trapping technique. Secondly, the bactericidal effect of the device was examined under a simulant condition in which Staphylococcus aureus suspended in 1 M H(2)O(2) was irradiated with laser light emitted from the test device, resulting in substantial reduction of the colony forming unit of the bacteria within a short time as 2 min. Finally, acute topical effect of the disinfection system on rat oral mucosa and wounded skin was evaluated by histological examination. No abnormal findings were observed in the buccal mucosal region treated three times with 1 M H(2)O(2) and irradiation. Similarly, no abnormal findings were observed during the healing of skin treated with 1 M H(2)O(2) and irradiation immediately after wounding. Since topical treatment with the novel disinfection technique utilizing the photolysis of H(2)O(2) had no detrimental effect on the oral mucosa and the healing of full thickness skin wounds in rats, it is expected that the acute locally injurious property of the disinfection technique is low.

500-Gray γ-Irradiation May Increase Adhesion Strength of Lyophilized Cadaveric Split-Thickness Skin Graft to Wound Bed.

Science.gov (United States)

Wei, Lin-Gwei; Chen, Chieh-Feng; Wang, Chi-Hsien; Cheng, Ya-Chen; Li, Chun-Chang; Chiu, Wen-Kuan; Wang, Hsian-Jenn

2017-03-01

Human cadaveric skin grafts are considered as the "gold standard" for temporary wound coverage because they provide a more conductive environment for natural wound healing. Lyophilization, packing, and terminal sterilization with gamma-ray can facilitate the application of cadaveric split-thickness skin grafts, but may alter the adhesion properties of the grafts. In a pilot study, we found that 500 Gy γ-irradiation seemed not to reduce the adherence between the grafts and wound beds. We conducted this experiment to compare the adherences of lyophilized, 500-Gy γ-irradiated skin grafts to that of lyophilized, nonirradiated grafts. Pairs of wounds were created over the backs of Sprague- Dawley rats. Pairs of "lyophilized, 500-Gy γ-irradiated" and "lyophilized, nonirradiated" cadaveric split-thickness skin grafts were fixed to the wound beds. Adhesion strength between the grafts and the wound beds was measured and compared. On post-skin-graft day 7 and day 10, the adhesion strength of γ-irradiated grafts was greater than that of the nonirradiated grafts. Because lyophilized cadaveric skin grafts can be vascularized and the collagen of its dermal component can be remodeled after grafting, the superior adhesion strength of 500-Gy γ-irradiated grafts can be explained by the collagen changes from irradiation.

Formation of fatty acid esterified vitamin D3 in rat skin by exposure to ultraviolet radiation

International Nuclear Information System (INIS)

Takada, K.

1983-01-01

The formation of fatty acid esters of vitamin D3 was demonstrated in rat skin exposed to artificial ultraviolet rays by using multi-dimensional high-performance liquid chromatography, ultraviolet spectrophotometry, and gas-liquid chromatography-mass spectrometry. This result indicated that the fatty acid esters of 7-dehydrocholesterol in rat skin (at least 80% of 7-dehydrocholesterol in rat skin is esterified) is also isomerized into vitamin D3 ester in vivo. The initial percentage of the esterified form was 84.3% and this did not significantly change up to the time when about half of the skin total vitamin D3 disappeared (2 days). Consequently, it was speculated that the vitamin D3 ester was delivered into the blood circulation from skin without having been hydrolyzed. This was supported by the presence of vitamin D3 ester in rat plasma exposed to ultraviolet radiation. In addition, in connection with the study of the restriction of vitamin D3 synthesis, distribution of total vitamin D3 in rat skin exposed to ultraviolet irradiation in vivo was compared with that in isolated skin exposed to ultraviolet radiation. The dermal layer of the isolated skin contained about 4 times more total vitamin D3 than that of in vivo skin. This finding suggests not only that ultraviolet rays could not penetrate deeply into the in vivo skin, but that the restriction of cutaneous synthesis of vitamin D3 observed in vivo may arise from this reduced penetration of ultraviolet rays

The differential response of the skin in young and old rats to a combination of X-rays and 'wet' or 'dry' hyperthermia

International Nuclear Information System (INIS)

Hamlet, R.; Hopewell, J.W.

1986-01-01

Hind feet of group of female rats aged 7, 14 and 52 weeks were X-irradiated at 20, 25 or 30 Gy. Hyperthermia (42.5 0 C for 1 h) was carried out immediately following irradiation using either 'wet' or 'dry' heat, by immersion in water or fluorocarbon liquid. Results demonstrated that 'wet' heat produced a consistently greater enhancement of the irradiation damage than 'dry'. The thermal enhancement ratio for irradiation plus 'wet' heat was approximately 1.5 and for irradiation plus 'dry' heat 1.17 to 1.39. Immersion of the feet in fluorocarbon liquid at 37 0 C did not significantly modify the irradiation response of the skin. The lower thermal enhancement ratios obtained using immersion in fluorocarbon liquid at 42.5 0 C are close to those obtained in large animal studies and similar to the limited amount of data from clinical studies where microwave or ultrasound heating techniques were used. It has been demonstrated that there are large age-related differences in the response of the rat foot skin to irradiation alone. It has also been shown, using rats of the same age, that the response to irradiation plus hyperthermia was less age dependent. (author)

Differences in pyrimidine dimer removal between rat skin cells in vitro and in vivo

International Nuclear Information System (INIS)

Mullaart, E.; Lohman, P.H.; Vijg, J.

1988-01-01

Pyrimidine dimers, the most abundant type of DNA lesions induced by ultraviolet light (UV), are rapidly repaired in human skin fibroblasts in vitro. In the same cell type from rats, however, there is hardly any removal of such dimers. To investigate whether this low capacity of rat skin cells to repair lesions in their DNA is an inherent characteristic of this species or an artifact due to cell culturing, we measured the removal of UV-induced pyrimidine dimers from rat epidermal keratinocytes both in vitro and in vivo. Epidermal keratinocytes in vitro were unable to remove any dimers over the first 3 h after UV-irradiation, while only about 20% was removed during a repair period of 24 h. In this respect, these cells were not different from cultured rat fibroblasts. In contrast to the results obtained with keratinocytes in vitro, we observed a rapid repair of pyrimidine dimers in UV-irradiated keratinocytes in vivo over the first 3 h; this rapid repair phase was followed by a much slower repair phase between 3 and 24 h. These results are discussed in terms of the possibility that mammalian cells are able to switch from one DNA repair pathway to another

Application of photo-magnetic therapy for treatment of skin radiation damage in rats

International Nuclear Information System (INIS)

Syimonova-Pushkar, L.Yi.; Gertman, V.Z.; Byilogurova, L.V.

2014-01-01

Local irradiation of rat skin causes the development of radiation ulcers in 60-70 % of the animals with the destruction of the structure in all layers of the skin. Spontaneous healing of radiation ulcer lasts at least two months with no complete skin recovery. Photo-magnetic therapy applied immediately after irradiation resulted in two-fold-decrease of frequency of radiation ulcer incidence, accelerated the complete healing for 3 weeks and to ameliorated their progress. Histological examination showed that the photo-magnetic therapy reduced the extent of damage to all layers of the skin with restoration of epidermis and dermis structure and reduced the degree of inflammatory and destructive processes in the dermis. Photo-magnetic therapy produces a significant positive treatment effect by significantly reducing the inflammatory and destructive processes in all layers of the skin, stimulates the blood flow recovery in damaged tissue both with fibroblast proliferation and synthesis activation of native collagen fibers and other components of connective tissue, so almost a month accelerates ulcer heating radiation

An Electron Microscopic Study of the Irradiation Effects on the Striated Duct Cells of the Submandibular Gland in Rats

International Nuclear Information System (INIS)

Lee, Kyu Chan; Lee, Sang Rae

1990-01-01

The purpose of this study was to investigate the effects of irradiation on the striated duct cells of the rat submandibular gland ductal tissues which control the characteristics of saliva. For this study, the experimental group was composed of 36 irradiated Sprague Dawley strain rats divided into 8 subgroups- 1 hour, 2 hours, 3 hours, 6 hours, 12 hours, 24 hours, 48 hours, 72 hours after irradiation. 4 non-irradiated rats were used as the control group. The experimental animals were singly irradiated with a dose of 18 Gy gamma ray to their head and neck region by the Co-6-teletherapy unit and sacrificed after each experimental duration. The specimens were examined with a light microscope with an H-E stain and with a transmission electron microscope. The results of this study were as follows. 1. In the light micrograph, a severe atrophic change occurred in the striated duct cells at 2 hours after irradiation and gradual recovery occurred from 6 hours after irradiation. 2. The nuclear chromosomes of the striated duct cells were changed granular at 2 hours after irradiation. Recovery was observed at 6 hours after irradiation. Nuclear bodies were also observed from 3 hours after irradiation. 3. The mitochondria of the striated duct cells had indistinct cristae at 2 hours after irradiation, and were degenerated or swollen at 3 hours after irradiation. They recovered, however, from 6 hours, with an increasing number at 48 hours a regular arrangement was observed at 72 hours after irradiation. 4. The microvilli showed atrophic changes at 2 hours after irradiation and were almost lost at 3 hours after irradiation. They were observed again from 48 hours after irradiation. 5. The rough endoplasmic reticulum and golgi body were not apparent at 1 hours after irradiation and were dilated with degeneration 2 hours after, but intact rough endoplasmic reticulum were observed from 3 hours after irradiation and developed well at 24 hours after irradiation. By the result of this

First experiences with super fractionated skin irradiations using large afterloading molds

International Nuclear Information System (INIS)

Fritz, Peter; Hensley, Frank W.; Berns, Christiane; Schraube, Peter; Wannenmacher, Michael

1996-01-01

optimization was mandatory to achieve a homogeneous dose distribution on the skin. Conclusion: Super fractionated brachytherapy with skin molds is an effective alternative for the treatment of skin metastases of breast cancer even if the skin is preirradiated. This method is economically advantageous compared to external beam therapy, which would require several weeks. At the curved chest wall, optimized molds can provide better dose homogeneity than abutted electron fields. Skin reactions are comparable to the sequelae of ortho volt irradiation. In preirradiated areas, PDR doses should be restricted to 40-45 Gy. PDR doses of 50 Gy seem to be the limit for tolerance even in previously unirradiated fields

The response of previously irradiated mouse skin to heat alone or combined with irradiation: influence of thermotolerance

International Nuclear Information System (INIS)

Wondergem, J.; Haveman, J.

1983-01-01

The effect of previous x-irradiation on the response to hyperthermia (44 0 C), x-irradiation, and irradiation combined with hyperthermia (43 0 C or 44 0 C) was studied in mouse foot skin. Irradiation of mice feet 90 days before, with 20 Gy, increased the subsequent response to heat alone, or combined with irradiation, as well as to irradiation alone. It had little effect on the thermal enhancement ratios for both acute and late skin reactions. Memory of the previous irradiation treatment could be masked when the temperature of the subsequent heat treatment alone, or combined with irradiation, was 44 0 C. Priming heat treatment induced resistance to a subsequent heat treatment and to a subsequent combined irradiation-heat treatment in normal as well as previously irradiated skin. When late skin reaction was considered, a larger 'memory' of the previous irradiation treatment was always evident, compared to acute skin reaction: the 'remembered' dose in the late skin reaction was about twice the 'remembered' dose in the acute reaction. (U.K.)

Electron microscopic observation of 137Cs-irradiated rat testis. Production of basal laminae for germ cells, despite their absence

International Nuclear Information System (INIS)

Sawada, Hajime; Esaki, Michiyo

2003-01-01

Whole body γ-ray irradiation of rats with caesium-137 ( 137 Cs) at embryonic day 20 induced marked reduction of the weight of the testis. Body weight and other tissues, however, seemed to remain normal. By light microscopy, complete loss of germ cells was observed in the testis. Other components, such as Sertoli cells and interstitial cells, seemed to be normal. The testes from day 8 postpartum rats contained very few spermatogonia compared with newborn rats, indicating loss of germ cells between days 0 and 8. In the adult, 137 Cs-irradiated testes showed two conspicuous features other than the loss of germ cells: empty vacuolar spaces between Sertoli cells and multilayered seminiferous tubule basal laminae (lamina densa). The junctional structures (ectoplasmic specializations) between Sertoli cells, however, seemed normal. The thickness of each layer of multilayered basal laminae was the same as that of normal rats and electron-lucent layers similar to lamina lucida were interposed between them. Of the empty vacuolar spaces between Sertoli cells, basal laminae bridge the gap. The basal laminae contained laminin, type IV collagen and heparan sulphate proteoglycan evenly distributed among layers, suggesting a normal composition. Rough estimation of the amount of basal laminae deposited in 137 Cs-irradiated rats indicates that it is within a range similar to that in normal testis. These features imply that Sertoli cells are, in part, determined perinatally to produce basal laminae for germ-line cells. (author)

Response of irradiated diet fed rats to whole body X irradiation

International Nuclear Information System (INIS)

Hasan, S.S.; Kushwaha, A.K.S.

1985-01-01

The response to whole body X irradiation has been studied in the brain of rats fed both on a normal diet (consisting of equal parts of wheat and gram flour) and on a low protein irradiated diet (consisting of a part of normal diet and three parts of wheat). The activity of enzymes related to the glucose metabolism (glucose 6-phosphate dehydrogenase and fructose diphosphate aldolase) is reduced, while that of peroxidant enzymes (catalase and lipid peroxidase) increased in the brain of rats that received a diet poor in proteins and irradiated diets (normal or hypoproteic). DNA and RNA levels and protein content show a significant reduction in the brain of rats with hypoproteic and irradiated diets. The total body irradiation causes serious alterations in the brain in animals with a hypoproteic malnutritions due both to a low protein and an irradiated diet. The brain of rats fed on a low protein and irradiated diet exhibits after whole body irradiation damages more severe than those in rats fed on a normal irradiated diet

Comparative studies in the cellular immunostimulation by whole body irradiation

International Nuclear Information System (INIS)

Dietz, R.; Schwarze, G.

1992-01-01

The effect of the cellular immune response by total body irradiation was investigated. The transplant survival (skin grafts) was determined as immune parameter. Donors were colony bred Wistar rats and recipients were colony bred Sprague Dawley rats. The investigations were carried out with irradiated rats and with rats irradiated after thymectomy and/or adrenalectomy as well as with animals without irradiation. A single total-body irradiation (1 and 2 Gy) was administered. The skin graft survival in irradiated rats was significant shorter (radiogenic immunostimulation) than in unirradiated rats; there were no significant differences between the operated (thymectomy and/or adrenalectomy) and not operated animals. Including precedent examinations this radiogenic immunostimulation is caused by relativly selective inactivation of T-suppressor cells. (orig.) [de

Relation between histamine release and dye permeability of pulmonary blood-air barrier in x-irradiated rat

Energy Technology Data Exchange (ETDEWEB)

Yamazaki, H [Kobe Univ. (Japan). School of Medicine

1976-04-01

The histamine-release kinetics and the influence of released histamine on the permeability of the pulmonary blood-air(BA) barrier during the early period after either whole-body or thoracic x irradiation of the rat were studied. Histamine contents of skin and lung of the irradiated rat decreased rapidly, reaching a minimum at 5 h, and this histamine depletion continued for at least 7 days. Conversely, in circulating blood histamine increased during the early period of 5 h and then decreased gradually. This early increase was linear up to 500R and then became saturated between 500 and 1,000R. Administration of polymixine B (5mg/100g body weight) to rats liberated histamine similarly. Rat sera containg histamine released soon after irradiation enhanced the capillary permeability of Evans blue(EB) in the guinea pig skin reaction, which was effectively countered by pretreatment of the guinea pig with anti-histaminic pyribenzamine (29..mu..g/100g body weight), but not by anti-serotonic chlorpromazine (0.3mg/100g body weight). Similarly, perhaps only the EB-bound serum albumin (EB-albumin), that was seen in alveolar perfusate, penetrated more through the pulmonary BA-barrier with increasing x-ray dose, in parallel with the increase in blood histamine. Pyribenzamine inhibited this effect effectively, but cysteamine (a radical scavenger) did so only partially. Thus, it seems possible that at soon after x irradiation the enhanced permeability of EB-albumin through the BA barrier of rat lung is due preferentially to the pharmacologic action of released histamine and subsidiarily to radiation damage to pulmonary cells.

First application of hemi-body electron beam irradiation for Kaposi sarcoma at the lower extremities.

Science.gov (United States)

Platoni, Kalliopi; Diamantopoulos, Stefanos; Dilvoi, Maria; Delinikolas, Panagiotis; Kypraiou, Efrosyni; Efstathopoulos, Efstathios; Kouloulias, Vassilis

2018-01-01

Kaposi's sarcoma (KS) is a systemic neoplastic disease that can present cutaneous symptoms and is usually treated with a systematic approach due to its extent. Due to its radiosensitivity, radiotherapy is considered one of its main treatments, for palliation and local control of the skin and mucosal lesions. The aim of this paper was to report the first case of KS treated by hemi-body electron irradiation protocol in Greece. A fractionated 40 Gy hemi-body electron irradiation was prescribed to a 60-year-old male patient with KS at his legs. Dose uniformity was verified on a daily basis by thermoluminescence dosimetry (TLD). The treatment resulted to complete clinical response. Limited irradiation-derived side effects appeared. This is the first case ever to be treated with hemi-body electron irradiation protocol in Greece. To the best of our knowledge, this is also the first time that a single field hemi-body electron beam irradiation at a total skin electron beam (TSEB)-like configuration is reported to be used for KS.

Blue LED irradiation to hydration of skin

Science.gov (United States)

Menezes, Priscila F. C.; Requena, Michelle B.; Lizarelli, Rosane F., Z.; Bagnato, Vanderlei S.

2015-06-01

Blue LED system irradiation shows many important properties on skin as: bacterial decontamination, degradation of endogenous skin chromophores and biostimulation. In this clinical study we prove that the blue light improves the skin hydration. In the literature none authors reports this biological property on skin. Then this study aims to discuss the role of blue light in the skin hydration. Twenty patients were selected to this study with age between 25-35 years old and phototype I, II and III. A defined area from forearm was pre determined (A = 4.0 cm2). The study was randomized in two treatment groups using one blue light device (power of 5.3mW and irradiance of 10.8mW/cm2). The first treatment group was irradiated with 3J/cm2 (277seconds) and the second with 6J/cm2 (555 seconds). The skin hydration evaluations were done using a corneometer. The measurements were collected in 7, 14, 21 and 30 days, during the treatment. Statistical test of ANOVA, Tukey and T-Student were applied considering 5% of significance. In conclusion, both doses were able to improve the skin hydration; however, 6J/cm2 has kept this hydration for 30 days.

The co-application effects of fullerene and ascorbic acid on UV-B irradiated mouse skin

International Nuclear Information System (INIS)

Ito, Shinobu; Itoga, Kazuyoshi; Yamato, Masayuki; Akamatsu, Hirohiko; Okano, Teruo

2010-01-01

The role of fullerene as a pro-oxidant or anti-oxidant in Ultraviolet B ray (UV-B)-induced disorders in mouse skin was investigated. Fullerene gave no photo-toxic effect to UV-B-irradiated mouse skin. Since erythema was concentrated at the pore circumference in a UV-B irradiation experiment in mouse skin, the sebaceous gland pairs was strongly implicated as a site for the generation of reactive oxygen species (ROS). In a histological evaluation of the skin stained with CH 3 MDFDA (ROS index) and YO-Pro-1 (apoptosis index), the fluorescence intensity of a sebaceous gland significantly increased with UV-B irradiation. With the application of fullerene to UV-irradiated mouse skin, no toxicity was recognized in comparison with the control, and erythema, the ROS index, and the apoptosis index decrease with the application of fullerene. Ascorbyl radical (AA·) increased with the application of ascorbate (AA) to UV-B-irradiated mouse skin, and AA· decreased with the application of fullerene. The co-application of AA and fullerene, which suppressed AA· in vitro, significantly suppressed erythema, and also suppressed both the ROS index and apoptosis index in mouse skin after UV-B irradiation. In both mouse skin at 48 h after UV-B irradiation and in an attempt to reproduce this phenomenon artificially in vitro, a similar high AA· peak (AA·/H· > 4) was observed in electron spin resonance (ESR) charts. The binding of fullerene with AA impairs the Fenton reaction between AA and Fe-protein based on the observation of ascorbate-specific UV absorption and a linear equation for the calibration curve. Therefore, fullerene may impair the intercalation of AA to a heme pocket by binding with AA. These results suggest that the co-application of AA and fullerene is effective against oxidative skin damage caused by UV-B irradiation, and the development of an AA· inhibitor such as fullerene should be useful for reducing organ damage associated with Fe-protein oxidation.

Immune reactivity after high-dose irradiation

International Nuclear Information System (INIS)

Gassmann, W.; Wottge, H.U.; von Kolzynski, M.; Mueller-Ruchholtz, W.

1986-01-01

Immune reactivity after total-body irradiation was investigated in rats using skin graft rejection as the indicator system. After sublethal irradiation with 10.5 Gy (approximately 50% lethality/6 weeks) the rejection of major histocompatibility complex allogeneic skin grafts was delayed significantly compared with nonirradiated control animals (28 versus 6.5 days). In contrast, skin grafts were rejected after 7.5 days in sublethally irradiated animals and 7 days in lethally irradiated animals if additional skin donor type alloantigens--namely, irradiated bone marrow cells--were given i.v. either simultaneously or with a delay of not more than 24 hr after the above conditioning regimen. These reactions were alloantigen-specific. They were observed in six different strain combinations with varying donors and recipients. Starting on day 2 after irradiation, i.v. injection of bone marrow gradually lost its effectivity and skin grafts were no longer rejected with uniform rapidity; skin donor marrow given on days 4 or 8 did not accelerate skin graft rejection at all. These data show that for approximately 1-2 days after high-dose total-body irradiation rats are still capable of starting a vigorous immune reaction against i.v.-injected alloantigens. The phenomenon of impaired rejection of skin grafted immediately after high-dose irradiation appears to result from the poor accessibility of skin graft alloantigens during the early postirradiation phase when vascularization of the grafted skin is insufficient

Skin changes in streptozotocin-induced diabetic rats.

Science.gov (United States)

Andrade, Thiago Antônio Moretti; Masson-Meyers, Daniela Santos; Caetano, Guilherme Ferreira; Terra, Vânia Aparecida; Ovidio, Paula Payão; Jordão-Júnior, Alceu Afonso; Frade, Marco Andrey Cipriani

2017-09-02

Diabetes can cause serious health complications, which can affect every organ of the body, including the skin. The molecular etiology has not yet been clarified for all diabetic skin conditions. Thus, this study aimed to investigate the changes of diabetes in skin compared to non-diabetic skin in rats. Fifteen days after establishing the diabetic status, skin samples from the dorsum-cervical region were harvested for subsequent analysis of alterations caused by diabetes. Our results demonstrate that diabetes stimulated higher inflammation and oxidative stress in skin, but antioxidant defense levels were lower compared to the non-diabetic group (p skin changes compared to non-diabetic skin in rats. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluation of morphological changes of the skin after radiation-induced injury in Wistar rats;Avaliacao de alteracoes morfologicas da pele apos lesao radioinduzida em ratos Wistar

Energy Technology Data Exchange (ETDEWEB)

Andrade, Cherley Borba Vieira de

2010-07-01

The cancer covers a heterogeneous group of more than 100 diseases with different etiology and prognosis. Radiotherapy is one of the most commonly used treatment modalities, aiming at the destruction of cancer cells, using ionizing radiation. One of the limiting factors of radiotherapy is that radiation promotes the death of tumor cells in addition to injure healthy tissue neighboring the tumor, and may cause their death. Irradiation of the skin, accidental or for therapeutic purposes can trigger many injuries culminating in fibrosis, which implies functional alteration of the body. The evaluation of morphological effects associated with skin irradiation becomes essential to develop more effective radiation strategies and decreased morbidity; and in case of accidents, proper handling of the victim.Evaluate radio-induced dermal changes using a Wistar rats model irradiated with 10, 40 and 60Gy. Male Wistar rats, aged approximately three months, were pre-anesthetized with midazolam and xylazine and anesthetized with sodium pentobarbital, shaved in the back, immobilized on polystyrene support in the prone position and irradiated with doses of 10, 40 and 60 Gy, with 4MeV nominal energy electron beams. The skin was irradiated in a 3cm{sup 2} field, and used 0.5cm of tissue equivalent material, to obtain a homogeneous dose distribution. After irradiation, the animals remained on constant evaluation, and the lesions were recorded photographically. The animals were divided into groups and were killed on the irradiation day, 5, 10, 15, 25 and 100 days after irradiation. The skin was fixed in 10% formaldehyde; the samples were embedded in paraffin and cut. The sections were stained with hematoxylin-eosin, picrosirius red and immuno stained with antibody anti-TGF beta1. Another part of the tissue was fixed in 2.5% glutaraldehyde and processed for scanning electron microscopy. It was observed macroscopically the appearance of skin lesions similar to burns on the entire

Electron-energy deposition in skin and thermoluminescence dosimeters

International Nuclear Information System (INIS)

Mei, G.T.Y.

1986-01-01

The primary object of this study was to investigate the relations between dosimeter response and skin dose resulting from beta-particle irradiation. This object was achieved by combining evaluation of beta-source energy spectra, calculation of flux energy spectra, and employment of a Monte-Carlo electron-transport computer program for determination of depth-dose distribution in multislab geometries. Intermediate results from three steps of evaluation were compared individually with experimental data or with other theoretical results and showed excellent agreement. The combined method is applicable for the electron agreement. The combined method is applicable for the electron energy range of 1 keV to 5 MeV for both monoenergetic electrons and energy-distributed electrons. Determination of dosimeter response - skin dose relationships for homogeneous atmospheric beta-particle sources and for two specific configurations of LiF TLD's have been carried out in this study. Information based on these calculations is of value in designing beta-particle dosimeters as well as in assessing potential occupational and public health risks associated with the nuclear power industry

Dynamic change in learning and memorising ability after hemispheric irradiation in rats

International Nuclear Information System (INIS)

Li Xuezhong; Bao Shiyao; Zhao Kangren; Tian Yie; Zhang Zhilin

2002-01-01

Objective: To study the sequence of learning and memory loss in the rat after hemispheric irradiation. Methods: After Sprague-Dawly (SD) female rats were anesthetized with chloral hydrate, their cerebral hemispheres were irradiated with a single dose of 5, 15 or 30 Gy by 4 MeV electron. On D3, D7, D30 and D60, the learning and memorizing ability was measured with the Y maze test. Results: On D3 and D7, the learning ability of SD rats was impaired most but partly restored in 1 to 2 months. In observation of memory loss, the intensity of cerebral function damage was in direct proportion to the increase of radiation dose. Conclusion: The learning and memorizing ability of rats can be damage by hemispheric irradiation with the severity of impairment and possibility of recruitment depending on the dose

Features of aseptic granulomatous imflammation in rats subjected to the chronic action of gamma irradiation in small doses

Energy Technology Data Exchange (ETDEWEB)

Goranov, I; Krushkov, I; Statelov, V; Bratanov, M; Nacheva, V; Gospodinova, D; Serafimov, A

1976-04-01

Wistar rats were given a Co-60 dose of 2 r/day over a period of 8 months, or a total dose of 400 r. Two sterile sponge scraps of the same size and form were introduced subcutaneously into the intracapsular space of rats in the control and irradiated groups. Cuts were made in the subcutaneous tissue near the implanted foreign bodies. A vigorous inflammatory reaction developed in the unirradiated animals. The skin granulated normally. The irradiated animals showed a general bleeding of the tissues at the implantation site. A number of deviations were noted during the tissue granulation of the irradiated rats. The migration of leucocytes into the infected site was decreased. The formation of macrophage elements and their activity was lower in the irradiated animals. The reaction of the connective tissue turned out to be a rather sensitive test of the disruptive effects of long-term irradiation. 11 refs.

A study on the effects of electron beam irradiation on tooth extraction wound healing in rats

International Nuclear Information System (INIS)

Suzuki, Akiyoshi

1983-01-01

The wound of the upper jaw 3 days after the first molar tooth extraction in female rats was exposed to 1,500 rads (Group 2) and 2,000 rads (Group 3) of the 10 MeV electron beams, and its pathohistological changes were compared with those of rats with the tooth extraction alone (control group). In the control group, the tooth extraction wound was covered with epithelium 10 days later and new bones were formed 17 days later. Wound healing with the epithelium was seen in all irradiated rats 24 days later. The formation of the new teeth was seen 24 days later in the Group 2 and 38 days later in Group 3. Cell infiltration under the epithelial layers was still observed in some of the Group 3, although the wound was covered with epithelium, and the new bone covering the extraction wound was formed 38 days later. Healing was prolonged in Group 3, as compared with that in Group 2. (Namekawa, K.)

The effect of high energy electron irradiation on blood-brain barrier permeability to haloperidol and stobadin in rats

Energy Technology Data Exchange (ETDEWEB)

Trnovec, T; Kallay, Z [Komenskeho Univ., Bratislava (Czechoslovakia). Inst. of Preventive and Clinical Medicine; Volenec, K [Karlova Univ., Hradec Kralove (Czechoslovakia). Lekarska Fakulta; Bezek, S; Durisova, M; Scasnar, V; Kubu, M [Slovenska Akademia Vied, Bratislava (Czechoslovakia). Ustav Experimentalnej Farmakologie; Svoboda, V [Medical Academy J.E. Purkyne, Hradec Kralove (Czechoslovakia)

1991-10-01

The heads of rats were irradiated by 4 MeV electrons in doses 90, 180, and 360 Gy. The observed times of deaths ranged 120-600, 60-420, and 150-370 min after 90, 180, and 360 Gy, respectively. A dose dependent decrease of the brain uptake index of haloperidol was observed 1 and 3 h post radiation. On the other hand an increased brain uptake index was found for stobadin after head irradiation with doses of 180 and 360 Gy. Regional cerebral blood flow, blood pressure, and heart rate were not significantly altered in the period following irradiation with 180 Gy. The observed changes in blood-brain barrier (BBB) permeability seem to be the result of the damaged function of morphological structures forming the BBB rather than altered regional blood flow. (orig.).

Oncogenic action of beta, proton, alpha and electron radiation on the rat skin

International Nuclear Information System (INIS)

Burns, F.J.

1980-01-01

Rat skin is being utilized as an empirical model for testing dose and time related aspects of the oncogenic action of ionizing radiation, ultraviolet light, and polycyclic aromatic hydrocarbons. Molecular lesions in the skin DNA, including, strand breaks and thymine dimers, are being measured and compared to tumor induction. The induction and repair kinetics of molcular lesions are being compared to split dose repair. Modifiers and radiosensitizers are being utilized to test specific aspects of a chromosome breakage theory of radiation oncogenesis

Effect of MgSO4 on expression of NSE and S-100 in rats brain tissue irradiated by 6 MeV electron beam

International Nuclear Information System (INIS)

Zhou Juying; Wang Lili; Yu Zhiying; Qin Songbing; Xu Xiaoting; Li Li; Tu Yu

2007-01-01

Objective: To explore the protection of magnesium sulfate (MgSO 4 ) on radiation-induced acute brain injuries. Methods: Thirty six mature Sprague-Dawley rats were randomly divided into 3 groups: blank control group, experimental control group and experimental administered group. The whole brain of SD rats of experimental control group and experimental-therapeutic group were irradiated with a dose of 20 Gy using 6 MeV electron beam. Magnesium sulfate was injected intraperitoneally into the rats of experimental-therapeutic group before and after irradiation for five times. The brain tissue were taken on days 1, 7, 14 and 30 after irradiation. Immunohistochemical method was used to detect the expressions of NSE and S-100 in brain tissue. All data were processed statistically with One-ANOVA analysis. Results: The expressions of NSE and S-100 after whole brain irradiation were time-dependent. Compared with blank control group, the expression of NSE in brains of experimental control group decreased significantly (P 4 can inhibit the expression of S-100, but induce the expression of NSE on radiation-induced acute brain injury. MgSO 4 has a protective effect on radiation-induced acute brain injury. (authors)

Effects of ultraviolet irradiation on skin of guinea pig

International Nuclear Information System (INIS)

Zhang Wenwen; Chen Qiang; Li Peng; Ling Ling; Lin Xiaochen; Ren Shuping; Liu Yajuan; Li Yun

2008-01-01

Objective: To explore the adverse effects of ultraviolet B (UV-B) on the skin of guinea pig. Methods: Guinea pig skin was irradiated with UV-B, the skin changes in external appearance, pathology, and the contents of OH and O 2 - produced in the skin were determined to study the adverse effects of UV-B on the guinea pig skin. Results: UV-B caused red swelling and desquamation of skin, with the increasing of the UV-B irradiation, the cells in stratum spinosum began to proliferate vigorously, the MDA and ROS contents in UVB radiation group were significantly higher than those in control group (P<0.05). Conclusion: UV-B can cause injury to guinea pig skin and has the potential to produce skin cancer. (authors)

Differential response of the skin in young and old rats to a combination of X-rays and 'wet' or 'dry' hyperthermia

Energy Technology Data Exchange (ETDEWEB)

Hamlet, R.; Hopewell, J.W.

1986-11-01

Hind feet of group of female rats aged 7, 14 and 52 weeks were X-irradiated at 20, 25 or 30 Gy. Hyperthermia (42.5/sup 0/C for 1 h) was carried out immediately following irradiation using either 'wet' or 'dry' heat, by immersion in water or fluorocarbon liquid. Results demonstrated that 'wet' heat produced a consistently greater enhancement of the irradiation damage than 'dry'. The thermal enhancement ratio for irradiation plus 'wet' heat was approximately 1.5 and for irradiation plus 'dry' heat 1.17 to 1.39. Immersion of the feet in fluorocarbon liquid at 37/sup 0/C did not significantly modify the irradiation response of the skin. The lower thermal enhancement ratios obtained using immersion in fluorocarbon liquid at 42.5/sup 0/C are close to those obtained in large animal studies and similar to the limited amount of data from clinical studies where microwave or ultrasound heating techniques were used. It has been demonstrated that there are large age-related differences in the response of the rat foot skin to irradiation alone. It has also been shown, using rats of the same age, that the response to irradiation plus hyperthermia was less age dependent.

Thyroid and pancreatic hormones in lethally irradiated rats

International Nuclear Information System (INIS)

Ahlersova, E.; Ahlers, I.; Praslicka, M.

1985-01-01

The concentrations of thyroxine, triiodothyronine and reverse triiodothyronine, glucagon and insulin in the serum or plasma were determined by radioimmunoassay in male rats of the Wistar strain 1, 6, 24, 48 and 72 hours after irradiation with 14.35 Gy (1500R) of X-rays. The irradiated and sham-irradiated rats were starved till examination. The concentrations of thyroxine and triiodothyronine dropped 6 hours after irradiation as compared with controls, the concentration of thyroxine also dropped after 72 hours. The level of reverse triiodothyronine in irradiated rats increased in the terminal period. The level of insulin dropped 24 hours after irradiation, at 72 hours it was higher than that in controls. The concentration of glucagon in irradiated rats increased in the terminal phase of radiation disease. The results document the diverse reaction of hormones in lethally irradiated rats and contribute to a deeper recognition of metabolic imbalance in the course of radiation disease. (author)

Growth regulation in X-irradiated mouse skin

International Nuclear Information System (INIS)

Elgjo, K.; Devik, F.

1978-01-01

Extracts of hairless mouse skin were tested for their content of epidermal G 1 inhibitor and G 2 inhibitor at daily intervals after X-irradiation with 4 500 or 2 250 rad. After either dose the skin extracts lacked G 1 inhibitory activity on days 5 and 6 respectively after irradiation. This coincided with the time when the epidermal mitotic rate again became normal and started a period of over-shoot. The time interval of 5 to 6 days corresponds to the turnover time of the differentiating cells in hairless mouse back epidermis. The findings indicate that the proliferating cells in epidermis can respond to changes in local chalone concentration, even after X-irradiation at the tested doses, and that the irradiated epidermal cell population still retains some important properties inherent in a cybernetically regulated system. The local G 2 -inhibitory activity also varied after irradiation, but these variations could not be directly related to the corresponding mitotic rates. (author)

Skin response to X-irradiation in the guinea-pig

Energy Technology Data Exchange (ETDEWEB)

Berry, R J; Mole, R H; Barnes, D W.H. [Medical Research Council, Harwell (UK). Radiobiological Research Unit

1976-12-01

Skin reaction to X-irradiation has been studied in the albino quinea-pig; early response in limited-field irradiations of the flank was comparable to that commonly seen in rodents, swine and man, and was dose-dependent with a dynamic range from mild erythema to moist desquamation. The peak early skin reaction was seen between 14 and 21 days after irradiation, and declined before 30 days except at the highest doses used. Fractionation of the X-ray dose at 24 hours resulted in a 'sparing' of about 340 rad. Permanent partial epilation was detectable at doses in excess of 1400 rad, and complete epilation at 1 year occurred in 50 per cent of irradiated fields at 1740 rad. Twenty-four hour two-dose fractionation resulted in a 'sparing' of about 500 rad for epilation. Palpable dermal 'fibrosis' was detectable at 3 months after irradiation in fields given more than 2070 rad, and at 1 year after irradiation in fields given more than 1800 rad; 50 per cent of fields showed palpable 'fibrosis' at 1 year at 1930 rad. Unlike domestic swine and man, skin fields in the quinea-pig showed no dimensional contraction after X-ray doses which produced gross early skin damage.

Effect of Co60 irradiation on capillary changes in the rat periosteum

International Nuclear Information System (INIS)

Hachiya, Hiroshi

1992-01-01

There exist considerable literatures on the vascular changes by tolerance dose or over tolerance dose irradiation, but little work has been done to study the effect of under tolerance dose irradiation on capillary changes. The purpose of this study was to observe capillary changes in the periosteum of rats after Co 60 irradiation. The vascularity of the periosteum was observed with vascular resin casts and scanning electron microscope at 3 days to 30 weeks after the heads were exposed to 10 Gy or 20 Gy of Co 60 γ ray. The results were as follows: In rats irradiated with 10 Gy, leakage of resin from the fine blood vessels was observed at 3 weeks. Decrease in the diameter of small blood vessels and decrease of capillary networks were observed at 5 weeks. These changes improved at 7 weeks. In rats irradiated with 20 Gy, leakage of resin and decrease in the diameter of the small blood vessels were observed at 2 weeks. The number of small blood vessels was decreased at 4 weeks. These changes improved at 7 weeks. (author) 60 refs

Determinants of skin sensitivity to solar irradiation

NARCIS (Netherlands)

Broekmans, W.; Vink, A.A.; Boelsma, E.; Klöpping-Ketelaars, W.A.A.; Tijburg, L.B.M.; Veer, van 't P.; Poppel, van G.; Kardinaal, A.F.M.

2003-01-01

Background: Acute effects of UV irradiation include UV-induced erythema. Sunlight plays an important role in the development of skin cancer. Several predictive factors of UV-induced erythema could also be predictive for skin cancer. Objective: Our objective was to quantitatively assess phenotypical

Erlotinib-induced rash spares previously irradiated skin

International Nuclear Information System (INIS)

Lips, Irene M.; Vonk, Ernest J.A.; Koster, Mariska E.Y.; Houwing, Ronald H.

2011-01-01

Erlotinib is an epidermal growth factor receptor inhibitor prescribed to patients with locally advanced or metastasized non-small cell lung carcinoma after failure of at least one earlier chemotherapy treatment. Approximately 75% of the patients treated with erlotinib develop acneiform skin rashes. A patient treated with erlotinib 3 months after finishing concomitant treatment with chemotherapy and radiotherapy for non-small cell lung cancer is presented. Unexpectedly, the part of the skin that had been included in his previously radiotherapy field was completely spared from the erlotinib-induced acneiform skin rash. The exact mechanism of erlotinib-induced rash sparing in previously irradiated skin is unclear. The underlying mechanism of this phenomenon needs to be explored further, because the number of patients being treated with a combination of both therapeutic modalities is increasing. The therapeutic effect of erlotinib in the area of the previously irradiated lesion should be assessed. (orig.)

Time series analysis of blood oxidative stress value in irradiated rats

International Nuclear Information System (INIS)

Kaneko, Takashi; Goto, Jun; Nomiya, Takuma; Nemoto, Kenji

2011-01-01

Indirect effect of ionizing-radiation causes free radicals and reactive oxgen species (ROS). These ROS interact with DNA or other organella, and cause oxidative damage to nucleic acids, membrane lipoprotein, mitchondria and others. The purpose of this study is to evaluate oxidative damage by irradiation using d-ROMs test. Electron beam was irradiated to the thigh of Wistar strain female rats, and reactive oxygen metabolites in the blood from these rats were measured and analysed. From the results, 2 Gy group shows significantly higher oxidative stress level than those of 0 Gy group especially in day 3 after irradiation. This oxidative stress definitely seemed to be caused by exposure to ionizing-radiation. In contrast, the group of 30 Gy-irradiation showed no significant increase of oxidative stress level. It was thought that oxidative stress caused by radiation was neutralized by expression of stress-induced antioxidant enzymes. These data resulted that d-ROMs test is useful for measuring oxidative stress levels of irradiated mammalian animals. (author)

The choice of sensitive skin layer responsible for aftereffects of daily irradiation of the skin

International Nuclear Information System (INIS)

Keirim-Markus, I.B.

1992-01-01

The choice of sensitive human skin layer manifesting in delayed period after daily irradiation of the human skin (stochastic and determined effects) was evaluated. It was established that delayed aftereffects of daily radiation of the skin manifested as epidem damages. This layer of papilla derma of 10-15 mg/cm 2 thick situated at the great part of body surface, 15 mg/cm 2 on dorsal side of hands and 40 mg/cm 2 on palms and pillows of the fingers. Sensitive layer of skin dosimeter for a control of daily irradiation of people must have the same geometry

Inter-individual and inter-cell type variation in residual DNA damage after in vivo irradiation of human skin

International Nuclear Information System (INIS)

Chua, Melvin Lee Kiang; Somaiah, Navita; Bourne, Sara; Daley, Frances; A'Hern, Roger; Nuta, Otilia; Davies, Sue; Herskind, Carsten; Pearson, Ann; Warrington, Jim; Helyer, Sarah; Owen, Roger; Yarnold, John; Rothkamm, Kai

2011-01-01

Purpose: The aim of this study was to compare inter-individual and inter-cell type variation in DNA double-strand break (DSB) repair following in vivo irradiation of human skin. Materials and methods: Duplicate 4 mm core biopsies of irradiated and unirradiated skin were collected from 35 patients 24 h after 4 Gy exposure using 6 MeV electrons. Residual DSB were quantified by scoring 53BP1 foci in dermal fibroblasts, endothelial cells, superficial keratinocytes and basal epidermal cells. Results: Coefficients of inter-individual variation for levels of residual foci 24 h after in vivo irradiation of skin were 39.9% in dermal fibroblasts, 44.3% in endothelial cells, 32.9% in superficial keratinocytes and 46.4% in basal epidermal cells (p < 0.001, ANOVA). In contrast, the coefficient of inter-cell type variation for residual foci levels was only 11.3% in human skin between the different epidermal and dermal cells (p = 0.034, ANOVA). Foci levels between the different skin cell types were correlated (Pearson's R = 0.855-0.955, p < 0.001). Conclusions: Patient-specific factors appear to be more important than cell type-specific factors in determining residual foci levels following in vivo irradiation of human skin.

The oncogenic action of ionizing radiation on rat skin: Progress report, February 1, 1988-January 31, 1989

International Nuclear Information System (INIS)

Burns, F.J.; Garte, S.J.

1988-01-01

Progress is described in 3 general areas corresponding to the specific aims of the proposal, including DNA strand breaks in the epidermis as a function of radiation penetration; oncogene activation in radiation-induced rat skin cancers; and carcinogenesis in rat skin induced by the neon ion beam. Numerous experiments have established that DNA strand breaks per unit dose in the rat epidermis are reduced by about 60% when the radiation penetration is reduced from 1.0 mm to 0.2 mm. The activation of oncogenes in the radiation-induced rat skin cancers followed a pattern. Four highly malignant cancers exhibited activation of K-ras and c-myc oncogenes, while the remaining 8 cancers exhibited only one or the other of these 2 oncogenes. Of 5 squamous carcinomas, 4 showed K-ras activation and 1 showed c-myc activation. Approximately 200 rats were exposed to the neon ion beam at the Bevalac in Berkeley, CA. The carcinogenicity of energetic electrons (2.0 MeV) was determined in conjunction with the neon ion experiment. It is too early to evaluate tumor incidence in the neon ion experiment, but for electrons an unusually large excess of connective tissue tumors, fibromas and sarcomas, have been observed so far. 59 refs., 2 tabs

Effect of x-ray irradiated rat fetus mandible

International Nuclear Information System (INIS)

Han, Chang Gun; You, Dong Soo

1978-01-01

The effect of irradiation of x-ray to developing rat mandible in the gestation stage was focused on the study of mandible development and the side effect of x-ray irradiation. The author studied the effect of x-ray irradiation with the gestated rat and their offsprings. 100 rads, 200 rads, 300 rads and 400 rads of x-ray was irradiated in regular order schematically at the lower left abdomen of gestated rat. 18 1/2 days after conception, their offsprings were sacrificed and examined their developing mandible with histological findings. The results were as followed. 1. In the 100-200 rads irradiated rat offsprings, bony trabeclulation was revealed irregular shape. In combine with this finding, osteoblast and fibroblast were appeared shrunken of their nucleus and location of eccentric position. 2. In the 300-400 rads irradiated rat offsprings, decrease of fibroblast and osteoblast appearance in the periosteum were prominently observed and empty lacunae were frequently appeared in their bone matrix. 3. The advent of osteoclast and resorption of cortical bone were appeared in proportion to increasing of x-ray irradiation.

Development of rat telencephalic neurons after prenatal x-irradiation

International Nuclear Information System (INIS)

Norton, S.

1979-01-01

Telencephalic neurons of rats, irradiated at day 15 of gestation with 125 R, develop synaptic connections on dendrites during maturation which appear to be normal spines in Golgi-stained light microscope preparations. At six weeks of postnatal age both control and irradiated rats have spiny dendritic processes on cortical pyramidal cells and caudate Golgi type II neurons. However, when the rats are 6 months old the irradiated rats have more neurons with beaded dendritic processes that lack spines or neurons and are likely to be degenerating neurons. The apparently normal development of the neurons followed by degeneration in the irradiated rat has a parallel in previous reports of the delayed hyperactivity which develops in rats irradiated on the fifteenth gestational day

Ontogenetic changes in the ultrastructure of rat hepatocyte organelles after prenatal x irradiation

International Nuclear Information System (INIS)

Chedid, A.; Nair, V.

1975-01-01

The effects of prenatal x irradiation on the development of hepatocyte organelles have been studied in Sprague-Dawley rats. Pregnant rats received 50 R to the pelvic region on the 13th gestation day (g.d.). Animals were sacrificed on g.d.'s 15 and 20, day of birth, and 5th postnatal day. The fetal and neonatal livers were obtained and processed for electron-microscopic examination. The most striking discernible change after irradiation involves the appearance of cytoplasmic ''polyribosomal aggregates'' in the hepatocyte specimens of 15th and 20th g.d.'s. In the control rat, smooth endoplasmic reticulum (SER) appears for the first time on 20th g.d., while no SER could be detected in the hepatocytes from the irradiated animals at this period nor on day of birth. In the irradiated animals, SER was observed on the 5th postnatal day. Our results are consistent with the hypothesis that lipid peroxidation membrane alteration, delayed appearance of SER, and ''polyribosomal aggregation'' may be sequentially linked events after prenatal x irradiation. (U.S.)

In vitro dermal absorption of pyrethroid pesticides in human and rat skin

International Nuclear Information System (INIS)

Hughes, Michael F.; Edwards, Brenda C.

2010-01-01

Dermal exposure to pyrethroid pesticides can occur during manufacture and application. This study examined the in vitro dermal absorption of pyrethroids using rat and human skin. Dermatomed skin from adult male Long Evans rats or human cadavers was mounted in flow-through diffusion cells, and radiolabeled bifenthrin, deltamethrin or cis-permethrin was applied in acetone to the skin. Fractions of receptor fluid were collected every 4 h. At 24 h, the skins were washed with soap and water to remove unabsorbed chemical. The skin was then solubilized. Two additional experiments were performed after washing the skin; the first was tape-stripping the skin and the second was the collection of receptor fluid for an additional 24 h. Receptor fluid, skin washes, tape strips and skin were analyzed for radioactivity. For rat skin, the wash removed 53-71% of the dose and 26-43% remained in the skin. The cumulative percentage of the dose at 24 h in the receptor fluid ranged from 1 to 5%. For human skin, the wash removed 71-83% of the dose and 14-25% remained in the skin. The cumulative percentage of the dose at 24 h in the receptor fluid was 1-2%. Tape-stripping removed 50-56% and 79-95% of the dose in rat and human skin, respectively, after the wash. From 24-48 h, 1-3% and about 1% of the dose diffused into the receptor fluid of rat and human skin, respectively. The pyrethroids bifenthrin, deltamethrin and cis-permethrin penetrated rat and human skin following dermal application in vitro. However, a skin wash removed 50% or more of the dose from rat and human skin. Rat skin was more permeable to the pyrethroids than human skin. Of the dose in skin, 50% or more was removed by tape-stripping, suggesting that permeation of pyrethroids into viable tissue could be impeded. The percentage of the dose absorbed into the receptor fluid was considerably less than the dose in rat and human skin. Therefore, consideration of the skin type used and fractions analyzed are important when using

Participation of bone marrow stromal cells in hemopoietic recovery of rats irradiated and then parabiosed with a non-irradiated litter mate, 2. Scanning and transmission electron microscopic observations

Energy Technology Data Exchange (ETDEWEB)

Kagawa, Koichi; Hayashi, Keiki; Awai, Michiyasu

1986-07-01

A light microscopical study on the recovery process after lethal irradiation and parabiosis has been made. Electron microscopically, in the bone marrow of lethally irradiated rats, hemorrhage occurred due to detachment of sinus endothelial cells. Afterwards, reticulum cells with small intracytoplasmic lipid droplets appeared. On day 3, these cells were rapidly replaced by the reticulum cells with large lipid droplets, and resulted in fatty marrow within 7 days. Spindle-shaped fibroblastoid reticulum cells were also observed. In the bone marrow of lethally irradiated rats parabiosed with non-treated litter mates, hemopoiesis was initiated by adhesion of nucleated blood cells to intricated fine cytoplasmic pseudopods of fat-storage cells. On days 3 to 5, in parallel with progressive hemopoietic recovery, fibroblastoid and reticulum cells with large lipid droplets decreased whereas those with small droplets increased. On day 8, reticulum cells with lipid droplets were seldom seen, and hemopoietic distribution became the same as normal. These results suggested that bone marrow stromal cells, namely reticulum, fat-storage, and fibroblastoid cells share a common cellular origin, and also that they regain their structure and function when fat-storage cells were placed in contact with hemopoietic precursor cells.

Effect of auto-skin grafting on bacterial infection of wound in rats inflicted with combined radiation-burn injury

International Nuclear Information System (INIS)

Ran Xinze; Yan Yongtang; Wei Shuqing

1992-01-01

Rats were exposed to 6 Gy whole body γ-ray irradiation from a 60 Co source followed by light radiation burn (15% TBSA, full thickness burn) from a 5 kw bromo-tungsten lamp. The effect of auto-skin grafting on invasive bacterial infection of wound in the rats with combined radiation-burn injury was studied, In the control group inflicted with combined radiation-burn injury but without skin grafting, bacteria were found on and in the eschars at 24th hour after injury, and in the subeschar tissue on 3rd day. Tremendous bacterial multiplication occurred from 7th to 15th day, and the amount of bacteria in the internal organs increased along with the increase of subeschar infection. At the same time, no bacterial infection was found in internal organs in auto-skin grafted group at 24th hour after injury. The results show that skin grafting can decrease or prevent bacterial infection in both subeschar tissue and internal organs

Electronic Cigarettes Are as Toxic to Skin Flap Survival as Tobacco Cigarettes.

Science.gov (United States)

Rau, Aline Sabrina; Reinikovaite, Viktorija; Schmidt, Eric P; Taraseviciene-Stewart, Laima; Deleyiannis, Frederic White-Brown

2017-07-01

Electronic cigarettes (e-cigarettes) have become increasingly popular. However, information about the health risks associated with e-cigarette use is sparse. Currently, no published studies examine the effects of chronic e-cigarette exposure on microcirculation or perfusion. Using a rat skin flap model, we examined the toxic microcirculatory effects e-cigarettes may have in comparison with tobacco cigarettes. Fifty-eight rats were randomized to either exposure to room air, tobacco cigarette smoke, medium-nicotine content (1.2%) e-cigarette vapor, or a high-nicotine content (2.4%) e-cigarette vapor. After 4 weeks of exposure, a random pattern, 3 × 9 cm skin flap was elevated on the dorsum of the rats. At 5 weeks, flap survival was evaluated quantitatively, and the rats were euthanized. Plasma was collected for nicotine and cotinine analysis, and flap tissues were harvested for histopathological analysis. Evaluation of the dorsal skin flaps demonstrated significantly increased necrosis in the vapor and tobacco groups. The average necrosis within the groups was as follows: control 19.23%, high-dose vapor 28.61%, medium-dose vapor 35.93%, and tobacco cigarette 30.15%. Although the e-cigarette and tobacco cigarette groups did not differ significantly, each individual group had significantly more necrosis than the control group (Pe-cigarette exposure groups had similar amounts of flap necrosis and hypoxia when compared with the tobacco cigarette exposure group. Nicotine-containing e-cigarette vapor is similarly toxic to skin flap survival as tobacco cigarettes.

[Effect of heijiang pill on radiation skin ulcer in rats].

Science.gov (United States)

Fu, Qi; Yang, Yang; Xu, Yong-Mei

2008-05-01

To investigate the relationship between single dosage of 60Co radiation and the degree of radiation-induced skin ulcers, and to evaluate the curative effect of Heijiang Pill (HJP) on skin ulcer induced by various dosages of radiation in rats. Sixty-six Wistar female rats were randomly divided into three groups, the blank control group (n = 6) and the two radiation groups, each 30 rats, with their right hind leg exposed respectively to 60 Gy and 40 Gy of 60 Co radiation. The time of emergence and degree of skin ulcer were recorded. Then rats in the two radiation groups were subdivided into the HJP group, the Ethacridine group and the model group, 10 in each group, they received corresponding treatment after ulceration, and the incidence, pathology, cure rate and cure time of skin ulcer were observed in the 90 days of observation. The incidence of skin ulcer was higher and occurred earlier in rats radiated with 60 Gy than that with 40 Gy (P ulcer healing rate in rats treated with HJP was higher than that treated with Ethacridine (P cure time in the HJP group was shorter (P ulcers. HJP can effectively cure radiation skin ulcer, and the effect is especially significant on the ulcer induced by low dose radiation.

Aggregation patterns of fetal rat brain cells following exposure to X-irradiation

International Nuclear Information System (INIS)

Shoji, R.; Suzuki, K.; Lee, I.P.

1980-01-01

In our search for a simplified in vitro test system to assess the teratogenic effects of physical factors, we studied the effects of total maternal body X-irradiation on aggregation patterns of enzymatically isolated fetal rat brain cells and on ultrastructural aggregate changes. The fetal brain cells were derived from day 14 gestation fetuses of pregnant Sprague-Dawley (CD strain) rats exposed to X-irradiation (25 - 200 R) one hour prior to sacrifice. Notable changes in the cell aggregates following X-irradiation included a reduction in cell aggregate size and an increase in number. The frequency of cell aggregates was higher in the treated than in the control group, and the mean diameter of cell aggregates was inversely related to increasing X-irradiation doses. Transmission electron microscopy revealed in isolated cells features of degenerative process which were similar to those found in intact fetal brain lesions caused by maternal X-irradiation. Furthermore, scanning electron microscopy revealed that inhibition of cell aggregation following X-irradiation could probably be attributed to inhibition of membrane filopodia development and a consequent failure of cell aggregates to fuse into a greater cell aggregate mass. These results suggest that the membrane factors which influence cell aggregation may be a useful parameter to assess early effects of X-irradiation-induced brain deformity. Presently, the cell aggregation culture system is being further evaluated as a short term test system for environmental teratogens

Comparative studies in the cellular immunostimulation by whole body irradiation. Vergleichende Untersuchungen ueber die zellulaere Immunstimulation durch Ganzkoerperbestrahlung

Energy Technology Data Exchange (ETDEWEB)

Dietz, R.; Schwarze, G. (Service de Radiologie, Centre Hospitalier de Luxembourg (Luxembourg) Medizinische Universitaetsklinik I, Homburg/Saar (Germany))

1992-04-01

The effect of the cellular immune response by total body irradiation was investigated. The transplant survival (skin grafts) was determined as immune parameter. Donors were colony bred Wistar rats and recipients were colony bred Sprague Dawley rats. The investigations were carried out with irradiated rats and with rats irradiated after thymectomy and/or adrenalectomy as well as with animals without irradiation. A single total-body irradiation (1 and 2 Gy) was administered. The skin graft survival in irradiated rats was significant shorter (radiogenic immunostimulation) than in unirradiated rats; there were no significant differences between the operated (thymectomy and/or adrenalectomy) and not operated animals. Including precedent examinations this radiogenic immunostimulation is caused by relativly selective inactivation of T-suppressor cells. (orig.).

Penetration of radionuclides across the skin. Rat age dependent promethium permeation through skin in vitro

International Nuclear Information System (INIS)

Kassai, Z.; Kassai, A.; Bauerova, K.; Koprda, V.; Harangozo, M.; Bendova, P.; Bujnova, A.

2003-01-01

The composition and the permeation properties of the skin are dependent on age. In the animal models for permation studies, age affects the mechanical as well as the permeation properties significantly. The time dependence of permeation of 147 Pm 3+ from aqueous solution was established by the animal skin model and the age dependence of promethium permeation through the skin was examined. The aim was to find the optimum rat skin age model for radionuclide permeation studies and to assess the relative importance of the main permeation pathways: transepidermal and transfollicular permeation. The skin from 5-day-old rats (5DR) was found to represent the optimum animal model to study transepidermal permeation of ions. The skin from 9-day-old rats (9DR) was selected to study transfollicular permeation of ions. Comparison of the permeated amounts of promethium through the skin without hairs (3 DR to 6 DR) and with hairs (7DR to 12DR) showed that the additional permation mode via follicles significantly contributed to the permeation rate and extent. (author)

Dose enhancement in the neighborhood of foreign bodies of the skin due to electron irradiation. A Monte-Carlo study using MCNP

Energy Technology Data Exchange (ETDEWEB)

Heide, Bernd [Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (DE). Inst. of Radiation Research (ISF)

2011-07-01

Foreign bodies penetrate into the skin in the region of the hand very frequently. If they are amicrobic, they can get stuck in the skin and do no harm to the body in normal case. However, when handling with a radioactive material, like an Sr-90/Y-90 syringe for example, a stuck foreign body in a finger can lead to an enhanced absorbed dose in the neighbourhood of a few hundredths of millimetre of a foreign body, which just is in magnitude of a body cell. In the following, we shall investigate the dose enhancement effect of graphite, lead, and gold when embedded in soft tissue and irradiated with electrons. This case study focusses on the region close to the piece of metal (foreign body) without consideration for the depth in which the foreign body is located. It holds some other idealised assumptions (concerning vacuum, shape and size of foreign bodies, tissue composition, and direction of the radiation field) but still is near to real situations. Among others, this case study served to estimate the dose enhancement in the neighbourhood of a pike of lead located at the right forefinger of a member of our Institute of Radiation Research after an Sr-90/Y-90 irradiation. (orig.)

Membrane potential of mitochondria from the liver of irradiated rats

International Nuclear Information System (INIS)

Fomenko, B.S.; Kaminin, A.N.; Elfimova, I.A.; Akoev, I.G.

1977-01-01

Measurements of the membrane potential of rat liver mitochondria 1 hour after irradiation with 800 R dose showed a decrease of its value. The potential decreased against the background of the activation of the generating mechanisms (the electron transport chain and ATP-ases). During energization of the membranes by the electron transport chain similar effect has been observed with different oxidation substrates (NAD linked substrates and succinate). It suggests that similar causative factors are at the basis of the changes observed. It is quite possible that the increase in the rate of both mitochondria respiration and ATP hydrolysis after the irradiation of animals was a consequence of the radiation-induced decrease in the potential value. (author)

Incidence and nature of tumors induced in Sprague-Dawley rats by gamma-irradiation

International Nuclear Information System (INIS)

Gross, L.; Dreyfuss, Y.; Faraggiana, T.

1988-01-01

In our previous studies carried out on inbred rats of the Sprague-Dawley strain, the tumor incidence was increased following irradiation (150 rads, 5 times, at weekly intervals), from 22 to 93% in females and from 5 to 59% in males. Experiments here reported suggest that 2 consecutive total-body gamma-irradiations of 150 rads each are sufficient to induce in rats the development of tumors, some malignant; 18 of 19 females (94.7%) developed tumors at an average age of 11.4 mo, and seven of the 14 males in this group (50%) developed tumors at an average age of 10.4 mo. In the second group, which received 3 consecutive gamma-irradiations, 20 of 23 females (86.9%) and 5 of 13 males (38.4%) developed tumors at average ages of 9.1 and 7.5 mo, respectively. In the third group, among rats which received 4 consecutive gamma-irradiations, 17 of 19 females (89.4%) and 4 of 12 males (33.3%) developed tumors at average ages of 9.4 and 10.5 mo, respectively. The etiology of tumors either developing spontaneously or induced by irradiation in rats remains to be clarified. Our attempts to detect virus particles by electron microscopy in such tumors or lymphomas have not been successful. As a working hypothesis, we are tempted to theorize that tumors or lymphomas developing spontaneously or induced by gamma irradiation in rats are caused by latent viral agents which are integrated into the cell genome and are cell associated, i.e., not separable from the rat tumor cells by conventional methods thus far used

Radiation injuries of the spinal marrow of rats after irradiation with fast electrons

International Nuclear Information System (INIS)

Bruce-Micah, B.

1973-01-01

Twenty rats were fractionated irradiated on five days of the week with fast electrons of 42 MeV energy with a single dose of 200 r/day. After 1,000 r, 2,000 r, 3,000 r and 4,000 r HD, the animals were supravitally fixed and the spinal marrow was removed. The histological investigation already showed after 1,000 r HD distinct changes of the nerve cells and nerve fibers whereas the vessels appeared not to be injured. After 2,000 r HD, vessel changes with edemas occured for the first time. After 3,000 r HD, all nerve cells were severely injured, the glia tissue was denser and the vessels were enlarged despite endothelial proliferations. Furthermore, there were big edemas around the vessels and a beginning of demyelinisation in the dorsal column. After 4,000 r HD, a great part of the nerve cells and also a few glia cells were destroyed. The remaining glia cells were pyknotic and had partly several nucleoli. The tractus of the white matter consisted almost only now of a glia felt. With a survival time of six weeks, the glia had greatly regenerated and numerous new capillaries had sprouted in the grey matter. The white matter was strongly demyelinised. In the front lateral column, small round necrosis centres were visible. 18 weeks after irradiation, the glia tissue had greatly rebuilt itself. There were only very few nerve cells present. The strong sprouting of new capillaries in the grey matter was most noticeable. The results show that the application of fast electrons is of no advantage as regards injuring the nerve tissue compared to X-rays. (orig./LH) [de

Early x-irradiation of rats

International Nuclear Information System (INIS)

Halasz, N.

1987-01-01

Low, repeated doses of X-rays from a Co 60 source were used to impair the development of the granule cells and their dendritic terminals in the olfactory bulb, and the resulting effect was studied under light and electron microscopes at 9 days of age. Irradiation of rats from embryonic day 18 (in utero) to postnatal day 5 resulted, among others, in maldevelopment of the (internal) granule cell and external plexiform layers. This was accompanied by a decrease in the number and the density of the granule cells, and the remaining granule cells contained less ribosomes, regardless of their position within the layer. This implies that both supposed subtypes of granule cells were effected. In the external plexiform layer, a reduced number of mature dendrodendritic synapses and signs of harmed granule gemmules were observed. The results suggest that intrauterinal plus postnatal irradiation with low, repeated doses of X-rays may be an effective tool impairing the development of prenatally forming neurons. (author)

Comparison of three techniques for skin total irradiation with electrons; Comparacao de tres tecnicas de irradiacao total da pele com eletrons

Energy Technology Data Exchange (ETDEWEB)

Batista, Delano V.S., E-mail: dbatista@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Instituto Nacional de Cancer (INCa), Rio de Janeiro, RJ (Brazil); Bardella, Lucia H. [Instituto Nacional de Cancer (INCa), Rio de Janeiro, RJ (Brazil); Rosa, Luiz A.R. da, E-mail: lrosa@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

2011-10-26

This paper compared three techniques of skin total irradiation with electrons: 1) horizontal positioning, 2) vertical positioning - rotatory technique and 3) vertical positioning - six fields technique. For that, a anthropomorphic phantom was positioned according to the recommendation for each technique and was i radiated at the linear accelerator by using the 6 MeV electrons. Radiochromic films were positioned on the surface in various regions of the phantom for measurement of absorbed dose. A ionization chamber was positioned inside of equivalent issue plates for dose evaluation due to the photons produced by electron stopping. The technique 2 and 3 have shown too similar in the results and number or discrepant points (8 and 10 respectively) of prescription lower than the technique 1 (22 points). The total body dose of photons of the 1, 2 and 3 techniques was 2.2%, 5.3% and 5.2% respectively

Infrequent alterations of the P53 gene in rat skin cancers induced by ionising-radiation

International Nuclear Information System (INIS)

Jin, Y.; Burns, F.J.; Garte, S.J.; Hosselet, S.; New York Univ., NY

1996-01-01

Radiation carcinogenesis almost certainly involves multiple genetic alterations. Identification of such genetic alterations would provide information to help understand better the molecular mechanism or radiation carcinogenesis. The energy released by ionizing radiation has the potential to produce DNA strand breaks, major gene deletions or rearrangements, and other base damages. Alterations of the p53 gene, a common tumour suppressor gene altered in human cancers, were examined in radiation-induced rat skin cancers. Genomic DNA from a total of 33rat skin cancers induced by ionizing radiation was examined by Southern blot hybridization for abnormal restriction fragment patterns in the p53 gene. A abnormal p53 restriction pattern was found in one of 16 cancers induced by electron radiation and in one of nine cancers induced by neon ions. The genomic DNA from representative cancers, including the two with an abnormal restriction pattern was further examined by polymerase chain reaction amplification and direct sequencing in exons 5-8 of the p53 gene. The results showed that one restriction fragment length polymorphism (RFLP)-positive cancer induced by electron radiation had a partial gene deletion which was defined approximately between exons 2-8, while none of the other cancers showed sequence changes. Our results indicate that the alterations in the critical binding region of the p53 gene are infrequent in rat skin cancers induced by either electron or neon ion radiation. (Author)

Association of malignancy with rapid growth in early lesions induced by irradiation of rat skin

International Nuclear Information System (INIS)

McGregor, J.F.

1979-01-01

Epithelial lesions induced by irradiation of rat skin were studied to determine (a) the relationship of malignancy to dose, (b) the types of lesions and circumstances leading to overt malignancy, and (c) the growth rates of lesions progressing to malignancy versus those of lesions remaining benign. High doses of radiation were shown to be associated with the production of epidermal cancers, the maximum yield being obtained at 6,400 rads. Conversely, a peak yield of noncancerous lesions was obtained at 1,600 rads. This association between malignancy and high dose was consistent for cancers evolving from warts, cysts, and chronic ulcers. Although the proportion of warts among the induced lesions was much higher than that of the cysts or chronic ulcers (76, 14, and 10%, respectively), the likelihood of warts becoming cancerous was substantially lower (14, 23, and 21%). The combined data for all doses showed that the latency period of the epidermal cancers was significantly (P = 0.015) shorter than that of the benign tumors. Rapid growth rates were observed for warts, cysts, and chronic ulcers progressing to overt cancer, and these did not overlap at any point on the growth scale with rates for benign tumors. This finding suggested that the potential for malignant development had been established early in the carcinogenic process, very likely at induction

Fibronectin distribution during the development of fetal rat skin

DEFF Research Database (Denmark)

Gibson, W T; Couchman, J R; Weaver, A C

1983-01-01

Fibronectin distribution during fetal rat skin development has been studied immunocytochemically at the light and electron microscope level from 16 days of gestation to birth. The dermal-epidermal junction, the dermis, and connective tissue around developing muscle were shown by light microscopy......, and there was also staining associated with the underlying fine collagen fibrils. These observations are further evidence for the proposed role of fibronectin as a mediator of the cell-matrix interactions which are of importance for tissue development and maintenance....

Soybean diet breast tumor incidence in irradiated rats

International Nuclear Information System (INIS)

Troll, W.; Wiesner, R.

1980-01-01

The relationship between feeding a diet rich in protease inhibitors and the reduction of mammary cancer induced by x-irradiation in Sprague-Dawley rats was examined. Of a total of 145 irradiated animals, 44% of the 45 rats fed a raw soybean diet containing a high concentration of protease inhibitor developed mammary tumors as compared to 74% of 50 rats fed a casein diet containing no protease inhibitor. Animals fed Purina rat chow which contained low levels of protease inhibitor exhibited a 70% mammary tumor incidence. No spontaneous neoplasms were found in any of the non-irradiated animals on the raw soybean diet whereas about 10% of the animals on the protease-free diet developed tumors. Thus, soybeans which are rich in protease inhibitors reduced the induction of mammary cancer in x-irradiated rats. This suggested that diets rich in protease inhibitors may contribute to reducing cancer incidence in man. (author)

Natural β-carotene and whole body irradiation in rats

International Nuclear Information System (INIS)

Ben-Amotz, A.; Rachmilevich, B.; Greenberg, S.; Sela, M.; Weshler, Z.

1996-01-01

β-Carotene and other carotenoids are reported to be potent free radical quenchers, singlet oxygen scavengers, and lipid antioxidants. Whole-body irradiation is known to cause an immunosuppression effect in mammals through the possible initiation and production of reactive oxygen species. We decided to test the possible antioxidative effect against whole-body irradiation of a natural β-carotene, composed of equal amounts of the all-trans and 9-cis isomers, obtained from the unicellular alga Dunaliella bardawil. Rats were fed on ground commercial food enriched with natural β-carotene (50 mg/kg diet). On completion of 1 week with β-carotene, the rats were exposed to a single dose of 4 Gy whole-body irradiation, after which their livers and blood were removed for β-carotene and retinol analysis in comparison with control livers of animals irradiated or not, or supplemented with β-carotene after irradiation. A normal increase in body weight with no ill effects was noted in the groups of rats whose diet was supplemented by β-carotene before and after irradiation, compared with the reduction in the specific growth rate in the group of rats irradiated without β-carotene. Liver β-carotene and retinol decreased significantly after irradiation compared with the rats which were not irradiated. This decrease was not shown in rats fed β-carotene prior to irradiation, and the effect of irradiation was partially cured by supplementation with β-carotene after irradiation. High-pressure liquid chromatography (HPLC) analysis of the irradiated animals showed a selective decline in 9-cis β-carotene and in retinol over all-trans β-carotene and retinyl esters. These results suggest that 9-cis β-carotene and retinol protect in vivo against the cellular damage by free radicals induced after whole-body irradiation. (orig.). With 1 fig., 2 tabs

Curcumin Stimulates the Antioxidant Mechanisms in Mouse Skin Exposed to Fractionated γ-Irradiation

Directory of Open Access Journals (Sweden)

Ganesh Chandra Jagetia

2015-01-01

Full Text Available Fractionated irradiation is one of the important radiotherapy regimens to treat different types of neoplasia. Despite of the immense therapeutic gains accrued by delivering fractionated irradiation to tumors, the radiation burden on skin increases significantly. Low doses of irradiation to skin adversely affect its molecular and metabolic status. The use of antioxidant/s may help to alleviate the radiation-induced changes in the skin and allow delivering a higher dose of radiation to attain better therapeutic gains. Curcumin is an antioxidant and a free radical scavenging dietary supplement, commonly used as a flavoring agent in curries. Therefore, the effect of 100 mg/kg body weight curcumin was studied on the antioxidant status of mice skin exposed to a total dose of 10, 20 and 40 Gy γ-radiation below the rib cage delivered as a single fraction of 2 Gy per day for 5, 10 or 20 days. Skin biopsies from both the curcumin treated or untreated irradiated groups were collected for the biochemical estimations at various post-irradiation times. The irradiation of animals caused a dose dependent decline in the glutathione concentration, glutathione peroxidase, and superoxide dismutase activities and increased the lipid peroxidation in the irradiated skin. Curcumin treatment before irradiation resulted in a significant rise in the glutathione concentration and activities of both the glutathione peroxidase and superoxide dismutase enzymes in mouse skin, whereas lipid peroxidation declined significantly. The present study indicates that curcumin treatment increased the antioxidant status of mouse exposed to different doses of fractionated γ-radiation.

Whole-body γ-irradiation decelerates rat hepatocyte polyploidization.

Science.gov (United States)

Ikhtiar, Adnan M

2015-07-01

To characterize hepatocyte polyploidization induced by intermediate dose of γ-ray. Male Wistar strain rats were whole-body irradiated (WBI) with 2 Gy of γ-ray at the age of 1 month, and 5-6 rats were sacrificed monthly at 0-25 months after irradiation. The nuclear DNA content of individual hepatocytes was measured by flow cytometry, then hepatocytes were classified into various ploidy classes. Survival percentage, after exposure up to the end of the study, did not indicate any differences between the irradiated groups and controls. The degree of polyploidization in hepatocytes of irradiated rats, was significantly lower than that for the control after 1 month of exposure, and it continued to be lower after up to 8 months. Thereafter, the degree of polyploidization in the irradiated group slowly returned to the control level when the irradiated rats reached the age of 10 months. Intermediate dose of ionizing radiation, in contrast to high doses, decelerate hepatocyte polyploidization, which may coincides with the hypothesis of the beneficial effects of low doses of ionizing radiation.

Some behavioral aspects of adult rats irradiated prenatally

International Nuclear Information System (INIS)

Vekovishcheva, O.Yu.; Blagova, O.E.; Borovitskaya, A.E.; Evtushenko, V.I.; Khanson, K.P.

1992-01-01

This is a study of the effects of prenatal irradiation on the behavior of rats. The experiments were performed on 42 eighteen month old rats of both sexes. Eight of the males and thirteen females had been irradiated prenatally. The results of this experiment indicated that in general, the activation of behavior, the appearance of aggression and the increase in chaos along with the presence of behavior poses were typical of the suppressed condition of the prenatal irradiated animal. Also, among prenatally irradiated animals, there was a greater degree of anxiety, a slow rate of adjustment to unfamiliar situations and unfriendly relationships between animals of the same sex. These results were compared with the results of behavioral experiments on irradiated adult rats

Electron microscopic studies on experimental skin cancer after combination treatment with X-ray, hematoporphyrin oligomer and caffeine

International Nuclear Information System (INIS)

Ueda, Keiichi; Ishiguro, Kazumori; Takaishi, Kimiko; Hatcho, Masahiro; Nakagawa, Shigemori

1992-01-01

The effect of combination treatment with X-ray, hematoporphyrin oligomer (HpO) and caffeine (Caf) was compared electron microscopically with that of a single use of these treatments. In experimental skin cancer, ultrastructural changes of nuclei and cytoplasm of tumor cells after combination treatment with HpO, X-ray and Caf showed more remarkable changes than in single X-ray irradiation and in HpO and X-ray irradiation. It is concluded that the combination treatment of HpO, X-ray and Caf is useful to the skin cancers in clinical practice. (author)

Electron microscopic studies on experimental skin cancer after combination treatment with X-ray, hematoporphyrin oligomer and caffeine

Energy Technology Data Exchange (ETDEWEB)

Ueda, Keiichi; Ishiguro, Kazumori; Takaishi, Kimiko; Hatcho, Masahiro; Nakagawa, Shigemori (Fukui Medical School, Matsuoka (Japan))

1992-05-01

The effect of combination treatment with X-ray, hematoporphyrin oligomer (HpO) and caffeine (Caf) was compared electron microscopically with that of a single use of these treatments. In experimental skin cancer, ultrastructural changes of nuclei and cytoplasm of tumor cells after combination treatment with HpO, X-ray and Caf showed more remarkable changes than in single X-ray irradiation and in HpO and X-ray irradiation. It is concluded that the combination treatment of HpO, X-ray and Caf is useful to the skin cancers in clinical practice. (author).

Selective lymphoid irradiation. V. Synergism with pretransplant thymectomy or thymic irradiation in cardiac transplantation in rats

International Nuclear Information System (INIS)

Iga, C.; Fawwaz, R.; Nowygrod, R.; Reemtsma, K.; Hardy, M.A.

1985-01-01

Selective lymphoid irradiation (SLI) using palladium-109-hematoporphyrin (Pd-H), given four days prior to transplantation, combined with two doses of antilymphocyte globulin (ALG) (10 mg, days -2 and -1), was evaluated as a method of induction of permanent heterotopic cardiac allograft survival in the highly histoincompatible rat strain combination of ACI (RT1(1))-to-Lewis (RT1a). Both Pd-H and ALG localize poorly in the thymus, so this study evaluated whether thymic irradiation (TI) or thymectomy (TX) of the adult recipient results in indefinite allograft survival. Immunosuppression with Pd-H or ALG alone gave a mean survival time (MST) of 6.7 +/- 0.6 days, but the combination of the two agents led to an MST of 17.6 +/- 3.4 days. When TI was combined with Pd-H and ALG, cardiac allograft survival was prolonged to 50.2 +/- 13.9 days, but TI alone showed an MST of 10.3 +/- 1.8 days. Permanent cardiac allograft survival (greater than 250 days) was achieved in all thymectomized recipients treated with the combination of Pd-H and a brief course of ALG. These animals also accepted second-set skin grafts and rejected third-party skin grafts following more than 150 days of ACI cardiac allograft survival. Thymic irradiation, although effective in acting synergistically with SLI and ALG, led to prolonged, but limited allograft survival, although thymectomy with SLI and ALG is synergistic in prolonging allograft survival permanently without chronic immunosuppression

The effect of anaesthesia on the radiosensitivity of rat intestine, foot skin and R-1 tumours

International Nuclear Information System (INIS)

Kal, H.B.; Gaiser, J.F.

1980-01-01

A comparison has been made of the effects of Nembutal (sodium pentobarbital) and Ethrane (2-chloro-1,1,2-trifluoroethyldifluoromethyl ether) anaesthesia on the radiation responses of rat intestine, foot skin and R-1 rhabdomyosarcoma. Single-dose experiments under Nembutal or short-lasting Ethrane anaesthesia resulted in equivalent radiosensitivities for the R-1 sarcoma and foot skin, whereas Ethrane induced radiosensitization in the intestine. In the Ethrane anaesthesia lasting 3 hours, and in the split-dose experiments, Ethrane inhibited repair of radiation-induced damage in the R-1 sarcoma and in the foot skin. It is therefore recommended that the use of Ethrane as an anaesthetic should be avoided in experiments designed to investigate repair of damage in fractionated studies or during protracted irradiation treatments. (UK)

Primary Observations on the Influence of 60Co Local Irradiation on Free Skin Flaps

Institute of Scientific and Technical Information of China (English)

杨建荣; 张园

2002-01-01

Objective To study the effect of postoperative radiation on free skin flaps.Methods Twenty-nine patients with free skin flaps applied to the plerosis of the postoperative defectwere followed up. Twenty-eight out of 29 patients received forearm free flaps while 1 had anterolater-al femoris skin flaps in a size ranging from 14 cm× 6 cm to 8 cm× 4 cm. These flaps were exposedto 60Co radiation ranging 40-69 Gy. Results Observation during irradiation: no visible changes ofskin flaps and oral mucous membrane were detected when irradiation dose was within 40 Gy; somechanges may be detected over 40 Gy. Observation 1 - 4 months after irradiation: pigmentations werefound in areas of erosion epidermis; skin flaps got dark but without evidence of necrosis. Observation2 years after irradiation: no necrosis happened in 29 skin flaps. Hairs were found on 15 of 29flaps. Sensation occurred within the margin of 1 cm. Conclusion Free skin flap can endure irradi-ation at the dose of 60 Gy.

Morphological studies on the healing process of extraction wound in irradiated rats

International Nuclear Information System (INIS)

Iizuka, Tadashi

1984-01-01

The present studies were performed to investigate the healing process of the extraction wound in irradiated rats and to clarify the effect of irradiation on bone formation and resorption. 282 Wistar rats of about 100g body weight were used. The region of the left upper molars of experimental rats was exposed to 1000 rad or 2000 rad of 60 Co. On the 7th day after irradiation, the left upper first molar of each rat was extracted. The rats were sacrificed at intervals of from 1 day to 28 days after extraction. Control rats were sacrificed at same intervals after extraction. The maxillary bone including the extraction wound was examined histologically, histometrically, histochemically and ultrastructurally. In irradiated rats, the healing process of extraction wound was disturbed. The osteoblastic new bone formation following production of granulation tissue and periosteal new bone formation was interfered. Histochemical examination revealed that the osteoblasts of irradiated rats reduced enzymatic activity compared with control rats. Ultrastructurally, the cytoplasmic organellae were poorly developed in the osteoblasts of irradiated rats and osteoid formation was reduced. In irradiated rats, the osteoclasts in the interradicular alveolar bone were more numerous and increased more rapidly as compared with control rats, whereas, histometrically, there was no significant difference in the amount of bone loss between control and irradiated rats. Histochemically, there was no distinct difference in the enzymatic activity in osteoclasts between control and irradiated rats. Ultrastructurally, the cytoplasmic organellae and ruffled border were poorly developed in the osteoclasts of irradiated rats. The findings suggest that irradiation induced cytological changes in not only oseoblasts but also osteoclasts and these changes resulted in the delayed healing of extraction wound. (author)

Apparatus for irradiation with electron beam

International Nuclear Information System (INIS)

Uehara, K.; Ito, A.; Nishimune, K.; Fujita, K.

1976-01-01

An irradiation apparatus with high energy electrons is disclosed in which a wire shaped or linear object to be irradiated is moved back and forth many times under an electron window so as to irradiate it with an electron beam. According to one feature of the invention, an electron beam, which leaks through gaps between the objects to be irradiated or which penetrates the objects to be irradiated, is reversed by a magnetic field approximately perpendicular to the scanning face of the electron beam by means of a magnet which is disposed under the objects to be irradiated, and the reversed electron beam is thereby again applied to the objects to be irradiated. A high utilization rate of the electron beam is accomplished, and the objects can be thereby uniformly irradiated with the electron beam. 4 claims, 6 drawing figures

Determining the mechanical properties of rat skin with digital image speckle correlation.

Science.gov (United States)

Guan, E; Smilow, Sarah; Rafailovich, Miriam; Sokolov, Jonathan

2004-01-01

Accurate measurement of the mechanical properties of skin has numerous implications in surgical repair, dermal disorders and the diagnosis and treatment of trauma to the skin. Investigation of facial wrinkle formation, as well as research in the areas of skin aging and cosmetic product assessment can also benefit from alternative methodologies for the measurement of mechanical properties. A noncontact, noninvasive technique, digital image speckle correlation (DISC), has been successfully introduced to measure the deformation field of a skin sample loaded by a material test machine. With the force information obtained from the loading device, the mechanical properties of the skin, such as Young's modulus, linear limitation and material strength, can be calculated using elastic or viscoelastic theory. The DISC method was used to measure the deformation of neonatal rat skin, with and without a glycerin-fruit-oil-based cream under uniaxial tension. Deformation to failure procedure of newborn rat skin was recorded and analyzed. Single skin layer failures were observed and located by finding the strain concentration. Young's moduli of freshly excised rat skin, cream-processed rat skin and unprocessed rat skin, 24 h after excision, were found with tensile tests to be 1.6, 1.4 and 0.7 MPa, respectively. Our results have shown that DISC provides a novel technique for numerous applications in dermatology and reconstructive surgeries. Copyright 2004 S. Karger AG, Basel

Squamous cell carcinoma arising in previously burned or irradiated skin

International Nuclear Information System (INIS)

Edwards, M.J.; Hirsch, R.M.; Broadwater, J.R.; Netscher, D.T.; Ames, F.C.

1989-01-01

Squamous cell carcinoma (SCC) arising in previously burned or irradiated skin was reviewed in 66 patients treated between 1944 and 1986. Healing of the initial injury was complicated in 70% of patients. Mean interval from initial injury to diagnosis of SCC was 37 years. The overwhelming majority of patients presented with a chronic intractable ulcer in previously injured skin. The regional relapse rate after surgical excision was very high, 58% of all patients. Predominant patterns of recurrence were in local skin and regional lymph nodes (93% of recurrences). Survival rates at 5, 10, and 20 years were 52%, 34%, and 23%, respectively. Five-year survival rates in previously burned and irradiated patients were not significantly different (53% and 50%, respectively). This review, one of the largest reported series, better defines SCC arising in previously burned or irradiated skin as a locally aggressive disease that is distinct from SCC arising in sunlight-damaged skin. An increased awareness of the significance of chronic ulceration in scar tissue may allow earlier diagnosis. Regional disease control and survival depend on surgical resection of all known disease and may require radical lymph node dissection or amputation

Twenty two cases of skin cancer following irradiation

International Nuclear Information System (INIS)

Ishihara, Kazuyuki; Hayasaka, Ken-ichi

1978-01-01

21 cases of spinocellular carcinoma (2 cases of them complicated basal-cell carcinoma) and a case of fibrosarcoma following irradiation were observed. The source which poses some problems in soft x-ray used for the treatment. Soft x-ray is used for the treatment of eczema, progressive keratodermia palmaris et plantaris, pustulosis palmaris et plantaris, trichophytia, hemangioma etc.. However, details of the irradiation are unknown in many of the cases. Carcinogenesis was noted 10 years at least-36 years at most after the irradiation. In 7 cases of 12 which received soft x-ray irradiation (including superficial therapy), multiple or double cancer was observed. In many of the cases, irradiation is repeated at low voltage, and radiation keratosis preceded cancerization. As the therapy of this type of keratosis, wide excision and skin grafting are generally recommended. The prognoses of the cases which received this therapy seem to be favorable. There were 6 cases of death out of 22 cases. The mortality (23.8%) is not high except for that of fibrosarcoma. Utilization of radiotherapy for skin diseases in future will be judged after a long-period followup. However, repeated irradiation for a long period, even if the source is extra-soft or limiting ray, should be avoided. (Ueda, J.)

Protective properties of the plasma of burnt and irradiated rats with respect to the lethal effect of endotoxins in vivo

International Nuclear Information System (INIS)

Budagov, R.S.; Chureeva, L.N.

1984-01-01

Intraperitoneal injection of endotoxins s. typhimurium and E. coli to preliminarily irradiated rats resulted in death of 80% of animals during 24 hours. At combined injection of endoxins with heterologic plasma of intact rats death decreased to 12 and 19% respectively. Deep burn of skin, acute radiation sickness and combined radiation-thermal injury did not eliminate the given phenomenon of humoral detoxication; at different periods after thermal, radiation and combined effects plasma of test rats produced protective effect practically the same as at the control

Sewage sludge irradiation with electrons

International Nuclear Information System (INIS)

Tauber, M.

1976-01-01

The disinfection of sewage sludge by irradiation has been discussed very intensively in the last few months. Powerful electron accelerators are now available and the main features of the irradiation of sewage sludge with fast electrons are discussed and the design parameters of such installations described. AEG-Telefunken is building an irradiation plant with a 1.5 MeV, 25 mA electron accelerator, to study the main features of electron irradiation of sewage sludge. (author)

Dietary protein effects on irradiated rat kidney function

International Nuclear Information System (INIS)

Mahler, P.A.; Yatuin, M.B.

1984-01-01

The authors have previously reported that unilaterally nephrectomized, kidney irradiated young male S-D rats have an increased median survival when placed on a low (4%) protein diet, as compared to a normal (20%) or high (50%) protein diet (200, 103, and 59 days respectively for 14 Gy irradiation). They have expanded these studies to examine the effects of irradiation and dietary protein levels on kidney function, by examining the parameters of blood urea nitrogen, serum creatinine, urine urea nitrogen, urine creatinine, urine osmolarity, urine volume, and water consumption. Irradiated 20% protein diet animals show an increase in water consumption and urine production and also a decrease in urine osmolarity, urine urea concentration and urine creatinine concentration. These changes all support the hypothesis the kidney irradiated rats fed a normal protein diet have a reduced capability to concentrate urine compared to nonirradiated control rats. Evaluation of the same parameters in irradiated rats fed a 4% protein diet does not indicate a similar loss of concentrating capability. Whether this protection is due to the growth inhibition of the 4% protein diet or some other phenomena remains to be determined

Effect of x-irradiation in rats bearing walker-256-carcinosarcoma and normal rats

International Nuclear Information System (INIS)

Ehara, Kazuhiko

1978-01-01

Serum protein fractions and total proteins were studied with bloods obtained from the rats exposed each to the partial-, whole-bodies and the transplanted tumors (Walker-256-carcinosarcoma transplanted in the right hind leg). The electrophoretic variation induced in the sera of tumor-bearing rats (Group II), and the content of total proteins decreased. Early irradiation to the tumor part of rats less induced the variations of the electrophoretic pattern and the decrease of the amount of serum total proteins. When the distant metastasis appeared during irradiation treatment, the electrophoretic patterns and content of total proteins changed proportionally to the variation in sera of Group II. On the other hand, the γ-globulin (G) fraction increased in the long-term survival rat. The separation of the rat serum β-G into two peaks of β 1 - and β 2 -G was shown only in Group IV (late irradiation to the right hind leg). This finding supposed that some factors involve in the sera of rats with transplanted primary tumor grown up to a fixed size and guessed the appearance of the distant metastasis during x-irradiation. The percentages of the albumin and γ-G decreased slightly and those of the α 1 -, α 2 - and β-G increased slightly in the rats with 300 rad partial-body (the right hind leg) x-irradiation daily for 20 days. The remarkable decrease of the albumin and γ-G, the increase of the α 1 - and β-G, the marked increase of the α 2 -G and the decrease of serum total proteins were demonstrated for the sera of rats with 1,000 rad whole-body x-irradiation at a time. These phenomena seem to be related to the destructive and reticuloendothelial injury by the exposure. (auth.)

Air-electron stream interactions during magnetic resonance IGRT. Skin irradiation outside the treatment field during accelerated partial breast irradiation

Energy Technology Data Exchange (ETDEWEB)

Park, Jong Min [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Advanced Institutes of Convergence Technology, Robotics Research Laboratory for Extreme Environments, Suwon (Korea, Republic of); Shin, Kyung Hwan; Wu, Hong-Gyun [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiation Oncology, Seoul (Korea, Republic of); Kim, Jung-in; Park, So-Yeon; Kim, Jin Ho [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Jeon, Seung Hyuck [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Choi, Noorie [Seoul National University College of Medicine, Department of Radiation Oncology, Seoul (Korea, Republic of)

2018-01-15

To investigate and to prevent irradiation outside the treatment field caused by an electron stream in the air generated by the magnetic field during magnetic resonance image-guided accelerated partial breast irradiation (APBI). In all, 20 patients who received APBI with a magnetic resonance image-guided radiation therapy (MR-IGRT) system were prospectively studied. The prescription dose was 38.5 Gy in 10 fractions of 3.85 Gy and delivered with a tri-cobalt system (the ViewRay system). For each patient, primary plans were delivered for the first five fractions and modified plans with different gantry angles from those of the primary plan (in-treatment plans) were delivered for the remaining five fractions to reduce the skin dose. A 1 cm thick bolus was placed in front of the patient's jaw, ipsilateral shoulder, and arm to shield them from the electron stream. Radiochromic EBT3 films were attached to the front (towards the breast) and back (towards the head) of the bolus during treatment. Correlations between the measured values and the tumor locations, treatment times, and tumor sizes were investigated. For a single fraction delivery, the average areas of the measured isodoses of 14% (0.54 Gy), 12% (0.46 Gy), and 10% (0.39 Gy) at the front of the boluses were as large as 3, 10.4, and 21.4 cm{sup 2}, respectively, whereas no significant dose could be measured at the back of the boluses. Statistically significant but weak correlations were observed between the measured values and the treatment times. During radiotherapy for breast cancer with an MR-IGRT system, the patient must be shielded from electron streams in the air generated by the interaction of the magnetic field with the beams of the three-cobalt treatment unit to avoid unwanted irradiation of the skin outside the treatment field. (orig.) [German] Beim Einsatz eines Magnetresonanztomographie(MRT)-gefuehrten Bestrahlungsgeraets kann durch die Wechselwirkung von Magnetfeld und Strahlenquelle unerwuenscht

Dose measurements in the treatment of mycosis fungoides with total skin irradiation using a 4 MeV electron beam

Energy Technology Data Exchange (ETDEWEB)

Poli, M.E.R. [Hospital Real e Benemerita Sociedade Portuguesa de Beneficencia (Brazil); Todo, A.S.; Campos, L.L. [Instituto de Pesquisas Energeticas e Nucleares, CNEN/SP Travessa R, Sao Paulo (Brazil)

2000-05-01

The total skin irradiation (TSI) is one of the most efficient techniques in the treatment administered with curative intent of the mycosis fungoides. The cure may be obtained in 10% to 40% of cases. The original Stanford University technique, created in 1960, was applied in a 4.8 MeV linear accelerator, that provided 2.5 MeV electrons in the patient, by the use of 4 couple beams with the patient placed in front of the beam, 3 meters distant from the apparatus. In this work we describe a 4 MeV electrons beam treatment method. We intend to improve the uniformity of the dose in the patient, as well, to reduce the problems with the overlapping treatment fields, that occurs in conventional treatment that uses 1 meter of focus-skin distance, and the treatment time to the patient. Only one modification was done in the apparatus: the dose rate for this treatment was doubled. The patient is placed on a rotative base and he assumes successively 6 positions: stand up and perpendicular to the beam, distant 2.83 meters from the gantry, with 60 degrees of interval between the rotations. In each position, the patient receives a couple of beams (the beam angulation is 19.5 degrees above the transversal axis in the middle of the patient and 19.5 degrees below it). The dosimetric data obtained were compared to the international protocols (AAPM). The delivered doses in the patient were measured with thermoluminescent dosimeters placed on skin surface and with Kodak XV-2 films placed between different slabs of an anthropomorphic phantom. The dose distribution in the phantom shows a good uniformity, in all thickness of interest, so it is possible to use this technique in the treatment of the mycosis fungoides as well Kaposi's sarcoma. (author)

Locomotor damage in rats after x-irradiation in Utero

International Nuclear Information System (INIS)

Mullenix, P.; Norton, S.; Culver, B.

1975-01-01

Alterations in gait were found in rats after whole-body irradiation with 125 R on day 14, 15, and 16 of gestation. No effects on locomotion were detected after irradiation on day 17 with 125 R or after irradiation on day 14 with 50 R. A technique was set up for quantitative evaluation of locomotion based on a modification of other methods. Walking patterns of irradiated rats were recorded, when they were adults, by requiring them to walk up a 10 0 incline through a corridor after their feet had been dipped in ink. Rats irradiated on gestational day 14 had an in-phase, hopping gait with the sine of the angle between the hind feet and the direction of progression over 0.9. Rats irradiated on gestational days 15 and 16 had an alternating, waddling gait with wider stance and broader angle than control rats. Histologic examination of serial sections of the brains of these rats showed that the 14-day rats lacked all telencephalic commissures except for a few fibers which crossed in some rats. There was a progressive improvement in the condition of the anterior and ventral hippocampal commissures up to day 17, but the corpus callosum and doral hippocampal commissure were lacking or markedly reduced in all day 17 rats. No animals showed damage to the mesencephalic posterior commissure. Since rats which used the in-phase mode of locomotion were never observed to use alternating gait, the possible causal relationship of the commissural damage to the altered locomotor patterns was considered. In view of the restricted period of damage found for the anterior and ventral hippocampal commissures and the restriction of altered locomotion to damage in the same period, primary involvement of the corpus callosum and dorsal hippocampal commissure could be excluded, but a possible role for the other telencephalic commissures remained

Radiotherapy-Induced Skin Reactions Induce Fibrosis Mediated by TGF-β1 Cytokine

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Cherley Borba Vieira de Andrade

2017-04-01

Full Text Available Purpose: This study aimed to investigate radiation-induced lesions on the skin in an experimental animal model. Methods and Materials: Cutaneous wounds were induced in Wistar rats by 4 MeV energy electron beam irradiation, using a dose rate of 240 cGy/min, for 3 different doses (10 Gy, 40 Gy, and 60 Gy. The skin was observed 5, 10, and 25 days (D after ionizing radiation exposition. Results: Infiltrate inflammatory process was observed in D5 and D10, for the 40 Gy and 60 Gy groups, and a progressive increase of transforming growth factor β1 is associated with this process. It could also be noted a mischaracterization of collagen fibers at the high-dose groups. Conclusion: It was observed that the lesions caused by ionizing radiation in rats were very similar to radiodermatitis in patients under radiotherapy treatment. Advances in Knowledge: This study is important to develop strategies to prevent radiation-induced skin reactions.

Effect of blood transfusion and skin grafting on rats with combined radiation-burn injury

International Nuclear Information System (INIS)

Yan Yongtang; Ran Xinze; Wei Shuqing

1990-01-01

The therapeutic effect of escharectomy and skin grafting at different times on rats with combined radiation-burn injuries (5 Gy total body irradiation plus flash radiation from a 5 kW bromotungstenic lamp to induce a 15% TBSA full thickness burn on back) treated with blood transfusion (BT) were studied. The treatment with BT and escharectomy plus skin grafting at 24, 48, and 72 h after injury showed significant therapeutic effects. In these treated groups, early recovery of WBC counts, the granulocytes and total lymphocytes, T, B-cells, bone marrow cells or CFU-F counts were evident within 30 days after injury. The 30-day survival rates of the skin grafts in the group treated with BT and skin grafting at 24 h after injury was 80%, in the group with skin grafting alone was 50%, while all the skin grafts sloughted within 30 days when the grafting was performed 48 and 72 h after injury. The 30-day survival rate of the recipients treated with skin grafting plus BT was higher than that of the animals with skin grafting alone. The results showed that satisfactory results were achieved with BT plus escharectomy and skin grafting within 24 h after injury, while skin grafting performed at 48 or 72 h after injury was ineffective for the survival of skin grafts

Spontaneous and x-irradiation induced carcinomas of small intestine in Wistar-Furth rats

Energy Technology Data Exchange (ETDEWEB)

Maeura, Y; Kosaki, G; Kitamura, H [Osaka Univ. (Japan). Faculty of Medicine; Nagatomo, T

1980-04-01

Spontaneous carcinoma of the small intestine in Wistar-Furth (WF) rats and carcinoma of the small intestine induced by local x-ray irradiation to the abdomen of WF rats without carcinoma were observed, and x-ray sensitivity of the small intestine mucosa was reported. Out of 19 rats with spontaneous carcinoma of the small intestine, 18 also had carcinoma of the colon, and 4 also had gastric cancer. They already had spontaneous carcinoma of the small intestine within 2 weeks after their birth, and the ratio of female and male was 13 : 6. Histological type of this carcinoma in all 19 rats was highly differentiated adenocarcinoma, and small intestine epithelium around carcinoma presented atypical epithelium. As to mice without carcinoma, x-ray, 1,000 R, 1,500 R, and 2,000 R, was irradiated to the abdomen of Sprague-Dawley (SD) and WF rats. In the irradiation with 1,000 R, carcinogenesis was not found in rats of both strains. In the irradiation with 1,500 R, carcinogenesis was hardly found, but in the irradiation with 2,000 R, carcinoma of small intestine occurred in 5 of 17 rats 15 weeks after the irradiation, 9 of 19 rats 25 weeks after the irradiation, and 9 of 14 rats 35 weeks after the irradiation. Histological type of carcinoma in irradiated rats was highly differentiated adenocarcinoma. The incidence of carcinoma in irradiated rats was higher in WF rats than SD rats through the course after the irradiation, which suggested that x-ray sensitivity of WF rats was higher than that of SD rats. Therefore, carcinoma of the small intestine in irradiated mice seemed to be induced by x-ray.

Late changes in pig skin after irradiation from beta-emitting sources of different energy

International Nuclear Information System (INIS)

Hamlet, R.; Heryet, J.C.; Hopewell, J.W.; Wells, J.; Charles, M.W.

1986-01-01

Skin fields were irradiated on 3-month-old pigs with Sr 90 , Tm 170 and Pm 147 sources, ranging in size from 1mm to 22.5 mm in diameter. The severity of late skin atrophy was assessed 2 years after irradiation by a comparison of the thickness of the dermis in exposed skin with that of an adjacent area of unirradiated skin. Quantitative measurements were made from histological sections. The maximum dermal thinning after Sr 90 β-irradiation was approx. 55%. Irradiation with Tm 170 produced a maximal thinning of approximately 35%. Irradiation with Pm 147 produced no observable atrophy in pig skin. These differences reflect the different depth-dose characteristics of the three β-emitting sources. Significant late dermal atrophy was seen after doses which only produced a minimal erythema in the acute phase of the reaction. There was also a lack of a field-size effect for late atrophy with all but the two smallest Sr 90 sources. This is the converse of the marked field-size effects reported for the acute skin reactions. (author)

Analysis of reactive aldehydes formed from the irradiated skin lipid, triolein

International Nuclear Information System (INIS)

Niyati-Shirkhodaee, F.; Shibamoto. Y.

1992-01-01

One of the major skin lipids, triolein, was irradiated by 300 nm uv light under conditions approximately those at the skin surface exposed to sunlight for different periods of time. Irradiated samples were analyzed for acrolein, formaldehyde, and acetaldehyde by gas chromatography. Acrolein formed was derivatized to more stable 1-methyl-2-pyrazoline with N-methylhydrazine and analyzed by a nitrogen-phosphorus specific detector. Formaldehyde and acetaldehyde formed were reacted with cysteamine to give thiazolidine and 2-methylthiazolidine, respectively and analyzed by a flame photometric sulfur specific detector. The maximum amount of acrolein (1.05 nmol/mg triolein) was formed after 6 hr irradiation. The maximum quantities of formaldehyde (6 nmol/mg triolein) and acetaldehyde (2.71 nmol/mg triolein) were formed after 12 hr irradiation. Both formaldehyde and acrolein have been known to cause skin irritation in the levels of 1 ppM

Acute effects of low-level laser therapy (660 nm) on oxidative stress levels in diabetic rats with skin wounds.

Science.gov (United States)

Denadai, Amanda Silveira; Aydos, Ricardo Dutra; Silva, Iandara Schettert; Olmedo, Larissa; de Senna Cardoso, Bruno Mendonça; da Silva, Baldomero Antonio Kato; de Carvalho, Paulo de Tarso Camillo

2017-09-01

Laser therapy influences oxidative stress parameters such as the activity of antioxidant enzymes and the production of reactive oxygen species. To analyze the effects of low-level laser therapy on oxidative stress in diabetics rats with skin wounds. Thirty-six animals were divided into 4 groups: NDNI: non-diabetic rats with cutaneous wounds that not received laser therapy; NDI: non-diabetic rats with cutaneous wounds that received laser therapy; DNI: diabetic rats with skin wounds who did not undergo laser therapy; DI: rats with diabetes insipidus and cutaneous wounds and received laser therapy. The animals were treated with LLLT (660 nm, 100 mW, 6 J/cm, spot size 0.028 cm). On the day of killing the animals, tissue-wrapped cutaneous wounds were collected and immediately frozen, centrifuged, and stored to analyze malondialdehyde (MDA) levels. Significant difference was observed within the groups of MDA levels (ANOVA, p = 0.0001). Tukey's post-hoc test showed significantly lower values of MDA in irradiated tissues, both in diabetic and non-diabetic rats. ANOVA of the diabetic group revealed a significant difference (p < 0.01) when all groups, except NDI and DI, were compared. LLLT was effective in decreasing MDA levels in acute surgical wounds in diabetic rats.

Physiologic consequences of local heart irradiation in rats

International Nuclear Information System (INIS)

Geist, B.J.; Lauk, S.; Bornhausen, M.; Trott, K.R.

1990-01-01

Noninvasive methods have been used to study the long-term cardiovascular and pulmonary functional changes at rest and after exercise in adult rats following local heart irradiation with single x-ray doses of 15, 17.5 or 20 Gy, and in non-irradiated control animals. Rats that had undergone a chronic exercise program were compared with untrained cohorts. The earliest dysfunction detected was an increased respiratory rate (f) at 10 weeks after irradiation in the highest dose group. In contrast, both telemetric heart-rate (HR) and rhythm and indirect systolic blood pressure measurements performed at rest only revealed changes starting at 43 weeks after irradiation with 20 Gy, up to which point the rats showed no clinical signs of heart failure. However, the number of minutes required for the recovery of the HR to pre-exercise levels following the implementation of a standardized exercise challenge was elevated in untrained rats compared with their trained cohorts at 18 weeks after irradiation with 20 Gy. Increases in recovery times were required in the two lowest dose groups, starting at 26 weeks after irradiation. It was concluded that the reserve capacity of the cardiopulmonary system masks functional decrements at rest for many months following local heart irradiation, necessitating the use of techniques which reveal reductions in reserve capacities. Further, the influence of local irradiation to the heart and lungs deserves closer scrutiny due to mutual interactions

Detection of prior irradiation in dried fruits by electron spin resonance (ESR)

Energy Technology Data Exchange (ETDEWEB)

Esteves, M P [Instituto Nacional de Investigacao Agraria (EAN), Oeiras (Portugal); Andrade, M E [Instituto Tecnologico e Nuclear (ITN), Sacavem (Portugal); Empis, J [Instituto Superior Tecnico (IST), Lisboa (Portugal)

1999-12-31

Complete text of publication follows. Dried almonds, raisins, dates and pistachio were irradiated using gamma radiation and electron beam with an average absorbed dose of 5 kGy. The radiation treatment was detected by ESR spectroscopy. Different parts of the dried fruits were analysed as follows: almonds: skin; raisins: dried pulp (at 30 deg C for one week); dates: dried pulp (at 30 deg C for one week) and stone; pistachio: nutshell. A Bruker ECS 106 EPR Spectrometer, at a microwave power of 0.4 mW, at room temperature was used. The analysis were carried out 2-3 months and 6 months after irradiation. A series of signals, tentatively described as `cellulose-like`, `sugar-like` and `complex` were observed, and some slight differences between spectra recorded from samples irradiated with gamma and electrons were evident.

Detection of prior irradiation in dried fruits by electron spin resonance (ESR)

International Nuclear Information System (INIS)

Esteves, M.P.; Andrade, M.E.; Empis, J.

1998-01-01

Complete text of publication follows. Dried almonds, raisins, dates and pistachio were irradiated using gamma radiation and electron beam with an average absorbed dose of 5 kGy. The radiation treatment was detected by ESR spectroscopy. Different parts of the dried fruits were analysed as follows: almonds: skin; raisins: dried pulp (at 30 deg C for one week); dates: dried pulp (at 30 deg C for one week) and stone; pistachio: nutshell. A Bruker ECS 106 EPR Spectrometer, at a microwave power of 0.4 mW, at room temperature was used. The analysis were carried out 2-3 months and 6 months after irradiation. A series of signals, tentatively described as 'cellulose-like', 'sugar-like' and 'complex' were observed, and some slight differences between spectra recorded from samples irradiated with gamma and electrons were evident

Comparison of different skin preservation methods with gamma irradiation.

Science.gov (United States)

Guerrero, Linda; Camacho, Bernardo

2017-06-01

Allografts are in constant demand, not only for burn victims, but also for all open wounds as "biological dressings". Tissue quality and security are two of the major concerns of Tissue Banks. There are limited studies published. There has been extensive discussion on the subject of preservation methods for cadaver skin. Most literature available comes from clinical reports. In this research, the authors compared 85% glycerolized non irradiated skin allografts with three glycerolized irradiated skin allografts (using different glycerol concentrations 50%, 70% and 85%). The evaluation of allograft quality was done by measuring physical and biological properties of such prepared human tissue grafts. In the histological structure evaluation changes were minimal and did not alter the skin structure. The clinical function of their behavior as temporal dressings was tested. They proved to have similar capabilities for improving granulating tissue and contributing to wound beds closure (Hickerson et al. (1994) [1]). Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

[UV-irradiation-induced skin cancer as a new occupational disease].

Science.gov (United States)

Diepgen, T L; Drexler, H; Elsner, P; Schmitt, J

2015-03-01

With the revision of the German Ordinance on Occupational Diseases, skin cancer due to UV irradiation was amended as a new occupational disease to the list of occupational diseases in Germany. The new occupational disease BK 5103 has the following wording: "Squamous cell carcinoma or multiple actinic keratosis of the skin caused by natural UV irradiation". Actinic keratoses are to be considered as multiple according to this new occupational diseases if they occur as single lesions of more than five annually, or are confluent in an area > 4 cm(2) (field cancerization). It is estimated that more than 2.5 million employees are exposed to natural UV irradiation due to their work (outdoor workers) in Germany and therefore have an increased risk of skin cancer. In this article the medical and technical prerequisites which have to be fulfilled for this new occupational disease in Germany are introduced.

Analysis of the collagen birefringence and the relative attenuation coefficient of health and burned skin irradiated with linearly polarized He-Ne laser

International Nuclear Information System (INIS)

Silva, Daniela de Fatima Teixeira da

2002-01-01

Low-intensity laser therapy is characterized by its ability to induce athermic effects and nondestructive photobiological processes. Although it has been in use for more than 40 years, this phototherapy is still not an established therapeutic modality. The objectives of this study were: to quantify the collagen fibers organization by polarized light microscopy in normal and burned skin samples at day 17 post-injury considering preferential axis as the animal's spinal column and aligning the linear laser polarization in two directions of polarization, parallel or perpendicular to this axis; to determine the relative attenuation coefficient for the intensity light by the technique of imaging the light distribution in normal and burned skin during wound healing process taking only parallel direction of polarization. To reach the objectives, burns about 6 mm in diameter were created with liquid N 2 on the back of the rats and the lesions were irradiated on days 3, 7, 10 and 14 post-wounding, D= 1 J/cm 2 , to investigate the effects of low-intensity linearly polarized He-Ne laser beam on skin wounds healing. Control lesions were not irradiated. The results have demonstrated that: the skin samples irradiated with linearly parallel polarized He-Ne laser beam showed collagen fibers more organized; burned skin samples presents a higher attenuation coefficient than normal skin samples. These results are important to optimize low intensity laser therapy dosimetry on acceleration wound healing. (author)

The morphological study of age-dependent effects in rat thyroids after γ-ray irradiation

International Nuclear Information System (INIS)

Zhang Xuefeng; Guo Lisheng; Tu Kaicheng; Xian Guoliang; Shi Feiman

1993-01-01

The purpose of this paper is to identify the differences in age-related harmful effects of the thyroid gland to ionizing radiation. The infant (0.5 month) and adult rats (2.5,6 and 15 months, respectively) were exposed to single γ-ray neck irradiation (0 Gy, as control, 0.5 Gy, 2 Gy, 4 Gy, 8 Gy, 16 Gy). The structure of irradiated thyroid gland under light and transmission electron microscope were observed at 6 weeks after partial irradiation. Some morphometric parameters were measured under light microscope. The results showed that the infant rat thyroids changed significantly after 0.5 Gy, but the adult thyroids expressed similar response after more than 2 Gy. Analyses of these data and information on pathology suggested that the infant thyroids were more radiosensitive than the adult ones

Tumorigenic action of beta, proton, alpha and electron radiation on the rat skin

International Nuclear Information System (INIS)

Burns, F.J.

1980-01-01

Rat skin is utilized as a model system for studying dose and time related aspects of the oncogenic action of ionizing radiation, ultraviolet light and polycyclic aromatic hydrocarbons. Molecular lesions in the DNA of the epidermis, including strand breaks and thymine dimers, are measured and compared to the temporal and dose related aspects of tumor induction. The induction and repair kinetics of molecular lesions are compared to split dose recovery as modified by sensitizers and type of radition of oncogenic damage

Radiation response of skin in young and old rats

Energy Technology Data Exchange (ETDEWEB)

Hamlet, R.; Hopewell, J.W. (Churchill Hospital, Oxford (UK))

1982-11-01

The results of this investigation clearly demonstrate the different radiation skin response in rats of differing ages. The reasons for these differences cannot be clarified until cell kinetic studies have been completed. These results obtained for rodent skin would appear to be in disagreement with the available data for human skin (Rubin and Casarett 1968) where no marked age-related changes were reported. Also, in pig skin studies (Hopewell and Young 1982) there was no evidence of an age effect in the dermal vascular response in 3-12-month-old animals. This may be related to the different tissue being investigated or it may reflect important species differences. Whatever the reasons behind these observations, the different skin response to radiation in rats of 7, 14 and 52 weeks of age has clearly been demonstrated and should be borne in mind when extrapolating data with rodent skin to the clinical situation.

Tissue glycogen and blood glucose in irradiated rats. II

International Nuclear Information System (INIS)

Ahlersova, E.; Ahlers, I.; Praslicka, M.

1980-01-01

Male rats of the Wistar strain were continuously irradiated with 0.57 Gy (60 R) of gamma rays from a 60 Co source. Irradiation lasted from 1 to 50 days in an experimental field where also control animals shielded from radiation were placed. After a 16 h starvation, the concentration of glucose in the blood and of glycogen in the liver and the heart was determined 1, 3, 7, 14, 21, 25, 32, 39 and 50 days after the beginning of irradiation. The concentration of blood glucose in irradiated rats did not practically differ from that of control animals during the whole period of investigation. The concentration of liver glycogen in irradiated animals was higher than that in the controls during all time intervals, except for day 1. The values of glycogen in the heart muscle were approximately identical in the irradiated and control rats, except for day 21 when they sharply increased in the irradiated animals. In addition to the investigation of blood glucose and tissue glycogen during continuous irradiation, these parameters were studied immediately, and 1, 6 and 12 months after continuous irradiation with a daily exposure of 0.57 Gy (60 R) up to a total exposure of 14.35 Gy (1500 R) of gamma rays. Considerably higher values of liver glycogen were detected in the irradiated rats immediately, and 1 and 6 months after the end of irradiation. (author)

Cholesterol metabolism in blood cells of irradiated rats

International Nuclear Information System (INIS)

Novoselova, E.G.; Kulagina, T.P.; Potekhina, N.I.

1985-01-01

Cholesterol metabolism in blood erythrocytes and lymphocytes of irradiated rats has been investigated. It has been found that at all terms and doses of irradiation, a suppression of the synthesis of erythrocyte cholesterol is observed. The increase of cholesterol quantiy in erythrocytes upon total gamma irradiation in the 10 Gr dose possibly is the result of growth of cholesterol transfer from plasma into erythrocyte cells. The study of the cholesterol synthesis in suspension of lymphocytes elminated from peripheral blood of control and irradiated rats has shown that at irradiation doses of 4 and 10 Gr in an hour acivation of cholesterol synthesis in vitro takes places

Protective properties of plasma of burnt and irradiated rats against lethal effect of endotoxins in vivo

Energy Technology Data Exchange (ETDEWEB)

Budagov, R S; Chureyeva, L N

1984-10-01

The purpose of this work was to estimate protective properties of plasma in disease with increased endotoxemia. Burns and acute radiation sickness were used as models of suppression of physiological mechanisms of detoxication. Experiments were performed on male Wistar rats and mice, which received 3rd degree burns over 15% of the body surface, whole body gamma irradiation at 7.5 Gr or both. At 3 hours, 3, 7 and 12 days after the exposure the animals were decapitated and blood collected. The irradiated mice received 0.2 ml endotoxin intraperitoneally, 1.0 ml freshly prepared rat plasma, then the lethality of the mice in 24 hours was observed. It was found that the plasma of intact rats was capable of decreasing the lethal effects of S. typhimurium and E. coli endotoxins in vivo in mice. Deep skin burns, acute radiation sickness and the combined effects of radiation and thermal injury did not change this phenomenon. The plasma of the experimental rats retained the protective properties at various periods of time after the thermal, radiation and combined exposures. The functioning of the humoral detoxication mechanism is radioresistant, indirectly indicating the nonimmunoglobulin nature of endotoxin inactivators. 19 references.

THE IMPACT OF ULTRAVIOLET IRRADIATION ON MORPHO-FUNCTIONAL STATE OF SKIN IN GUINEA PIGS.

Science.gov (United States)

Myronchenko, S; Naumova, O; Zvyagintseva, T

2016-11-01

The purpose of this study was to assess the impact of ultraviolet irradiation (UV) on morphological and functional condition of the skin in guinea pigs. The study involved 30 albino guinea pigs weighing 400-500 g subjected to local exposure to UV irradiation. Control group consisted of intact guinea pigs. Histological studies of the skin were carried out at different stages of the trial (2 hours, 4 hours, 3 days, 8 days following the exposure). Microscopic examination showed morphological signs of acute inflammation in the skin of animals within the first three days following the exposure to UV irradiation. Within 2 hours following the exposure to UV irradiation these changes were minimal with signs of mild exudative changes. In 4 hours after the exposure histological changes increased. The specimens were also found to contain altered apoptotic keratinocytes (sunburn cells). Histopathological changes persisted and reached maximum severity by the 3rd day. Within post-erythema period (the 8th day) proliferative, hyperplastic, degenerative and dystrophic changes in the skin persisted. The prolonged nature of the changes in the skin is suggestive of the development of chronic inflammation in the skin of guinea pigs subjected to local exposure to UV irradiation.

Pathogenesis of post-irradiation infection. 2. Role of neutrophils in the defence of irradiated rats against Yersinia enterocolitica

International Nuclear Information System (INIS)

Bazin, Herve; Platteau, Bernadette; Bakour, Rabah; Janssens, Michele; Wauters, Georges

1982-01-01

Wistar R inbred rats showed a substantial mortality when they were given Yersinia enterocolitica eight days after a 6.5 Gy total body irradiation. The possibility to abolish the high susceptibility of these irradiated rats to Yersinia enterocolitica by intravenous injections of isogenic neutrophils is presented: irradiated rats injected with 7 to 10.10 7 isogenic neutrophils, by the intravenous route, just before or after the administration of Yersinia enterocolitica, were not susceptible. On the contrary, control irradiated rats, not transfused, were killed by the same bacterial challenge [fr

Pathogenesis of post-irradiation infection. 2. Role of neutrophils in the defence of irradiated rats against Yersinia enterocolitica

Energy Technology Data Exchange (ETDEWEB)

Bazin, H.; Platteau, B.; Bakour, R.; Janssens, M.; Wauters, G. (Universite de Louvain, Bruxelles (Belgium))

1982-07-01

Wistar R inbred rats showed a substantial mortality when they were given Yersinia enterocolitica eight days after a 6.5 Gy total body irradiation. The possibility to abolish the high susceptibility of these irradiated rats to Yersinia enterocolitica by intravenous injections of isogenic neutrophils is presented: irradiated rats injected with 7 to 10.10/sup 7/ isogenic neutrophils, by the intravenous route, just before or after the administration of Yersinia enterocolitica, were not susceptible. On the contrary, control irradiated rats, not transfused, were killed by the same bacterial challenge.

Acute skin reaction after fractionated irradiation

International Nuclear Information System (INIS)

Kozubek, S.

1983-01-01

Experimental data on acute mouse and pig skin reaction after fractionated γ or X irradiation have been analysed in terms of a new cell tissue kinetic model. The exponential-quadratic and generalized Huggett formulae have been used for cell lethality description. Fairly better results could be demonstrated with generalized Huggett formula. The speed of repopulation has been determined for fractionated regimes as well as for some irregular schedules. The repopulation is slower in the case of fractionated treatment. On considering the normal cell loss factor in the tissue, minimum cell cycle time has been calculated. Its value differs for various strains (Tsub(d)=28.8 hours for SAS/TO mice and Tsub(d) < or approximately 17 hours for WHT/Ht mice) and does not differ for plucked skin. The repopulation has been shown to follow exponential dependence after some latent period. Other factors influencing the effectiveness of radiation treatment (the length of the latent period or the changes of the survival curve during fractionated irradiation) have been considered, too

Effects of combined radiation-burn injury on survival rate of allogeneic skin grafts and immune reaction in rats

International Nuclear Information System (INIS)

Ran Xinze; Yan Yongtang; Cheng Tianmin; Li Yuan; Wei Shuqing

1996-01-01

The effects of combined radiation-burn injury on survival rate of allogeneic skin grafts and immune reaction were studied in rats with combined injury of 3-8 Gy 60 Co γ-ray irradiation plus 15% total body surface area full thickness burn induced by exposure to a 5 kw bromotungsten lamp. The allogeneic skin was transplanted 24 hours after injury. It was found that all the skin grafts failed to survive in 10 days and the immune reaction significantly increased in the early stage of burn injury. But the immune reaction was obviously suppressed by the combined radiation-burn injury. The survival rates of skin grafts were 20% and 30% in the combined injury of burn plus 3 and 4 Gy irradiation respectively. When the radiation doses increased to 5,6 and 8 Gy, the survival rates elevated to 69%, 88% and 100% respectively (in the group of 8 Gy, bone marrow transplantation was conducted before receiving skin graft). At day 30 post-transplantation the survival rates were still 36%, 42% and 100% respectively. Compared with burn group, there was a significant difference in survival rate when the radiation doses were higher than 5 Gy. These results indicate that the survival rate of the allogeneic skin graft increases concurrently with the increase in radiation dose and decreases with the elapse of the post-transplantation time

Hypertension after bilateral kidney irradiation in young and adult rats

International Nuclear Information System (INIS)

Jongejan, H.T.; van der Kogel, A.J.; Provoost, A.P.; Molenaar, J.C.

1987-01-01

The mechanism of a rise in blood pressure after kidney irradiation is unclear but most likely of renal origin. We have investigated the role of the renin-angiotensin system and dietary salt restriction in the development of systolic hypertension after bilateral kidney irradiation in young and adult rats. Three to 12 months after a single X-ray dose of 7.5 or 12.5 Gy to both kidneys of young and adult rats, the systolic blood pressure (SBP) and plasma renin concentration (PRC) were measured regularly. A single X-ray dose of 12.5 Gy caused a moderate rise in SBP and a slight reduction in PRC in both young and adult rats. A dose of 7.5 Gy did not significantly alter the SBP or PRC during the follow-up period of 1 year. In a second experiment, the kidneys of young rats received an X-ray dose of 20 Gy. Subsequently, rats were kept on a standard diet (110 mmol sodium/kg) or a sodium-poor diet (10 mmol sodium/kg). On both diets, SBP started to rise rapidly 3 months after kidney irradiation. Sodium balance studies carried out at that time revealed an increased sodium retention in the irradiated rats compared to controls on the same diet. In rats on a low sodium intake, there was neither a delay nor an alleviation in the development of hypertension. Compared to controls, the PRC tended to be lower in irradiated rats up to 4 months after irradiation. Subsequently, malignant hypertension developed in all 20 Gy rats, resulting in pressure natriuresis, stimulating the renin-angiotensin system. Our findings indicated that hypertension after bilateral kidney irradiation was not primarily the result of an activation of the renin-angiotensin system. Although there were some indications that sodium retention played a role, dietary sodium restriction did not influence the development of hypertension

Prophage lambda induction (Inductest) of blood of rats fed irradiated spices

Energy Technology Data Exchange (ETDEWEB)

Farkas, J; Andrassy, E [Koezponti Elelmiszeripari Kutato Intezet, Budapest (Hungary)

1981-01-01

Lysogenic Escherichia coli K12 strains Nos. GY 5023: envA uvr/sup +/ (lambda) and GY 5027: envA uvrB (lambda) were used as test organisms and E.coli strain No. GY 4015 as the indicator to investigate prophage induction (Inductest) of blood samples of CFY rats fed with black pepper and spice mixture treated with gamma radiation. The dose levels applied for the irradiation of spices were 0.5 and 15 kGy. In the rat feed, the applied concentration of ground black pepper was 3.5%, and that of the spice mixture (: mild paprika, black pepper, allspice, coriander, marjoram, cumin and nutmeg) was 25%. Blood samples were taken for prophage induction after six days' feeding with the tested diet. Tests with pepper were performed both within two weaks after irradiation and again after 90 days of storage following irradiation, while with the spice mixture, Inductest was performed with the blood of rats fed with a spice mixture irradiated 90 days before the start of the feeding test. Neither the blood of rats fed with irradiated pepper nor that of rats fed with irradiated spice mixture did increase, to a statistically significant degree, the occurrence of prophage induction as compared with blood samples of rats fed with a diet containing untreated spices or with commercial rat feed. In agreement with earlier microbial mutagenicity tests performed with extracts of irradiated spices and urine of rats fed with irradiated spices, neither did the present results indicate that spices irradiated with 5 and 15 kGy or their metabolites would be of DNA-modofying potential.

Prophage lambda induction (Inductest) of blood of rats fed irradiated spices

International Nuclear Information System (INIS)

Farkas, J.; Andrassy, E.

1981-01-01

Lysogenic Escherichia coli K12 strains Nos. GY 5023: envA uvr + (lambda) and GY 5027: envA uvrB (lambda) were used as test organisms and E.coli strain No. GY 4015 as the indicator to investigate prophage induction (Inductest) of blood samples of CFY rats fed with black pepper and spice mixture treated with gamma radiation. The dose levels applied for the irradiation of spices were 0.5 and 15 kGy. In the rat feed, the applied concentration of ground black pepper was 3.5%, and that of the spice mixture (: mild paprika, black pepper, allspice, coriander, marjoram, cumin and nutmeg) was 25%. Blood samples were taken for prophage induction after six days' feeding with the tested diet. Tests with pepper were performed both within two weaks after irradiation and again after 90 days of storage following irradiation, while with the spice mixture, Inductest was performed with the blood of rats fed with a spice mixture irradiated 90 days before the start of the feeding test. Neither the blood of rats fed with irradiated pepper nor that of rats fed with irradiated spice mixture did increase, to a statistically significant degree, the occurrence of prophage induction as compared with blood samples of rats fed with a diet containing untreated spices or with commercial rat feed. In agreement with earlier microbial mutagenicity tests performed with extracts of irradiated spices and urine of rats fed with irradiated spices, neither did the present results indicate that spices irradiated with 5 and 15 kGy or their metabolites would be of DNA-modofying potential. (author)

Effect of repeated ultraviolet irradiation on skin of hairless mice

International Nuclear Information System (INIS)

Alpermann, H.; Vogel, H.G.

1978-01-01

The effect of repeated UV-irradiation on mechanical and biochemical parameters was studied in skin of hairless mice. uV-A irradiation for a period of 1 h daily over 8 weeks caused only a slight increase in skin thickness and a decrease in ultimate strain. The changes induced by UV-B and C, however, were quite remarkable. Skin thickness was increased depending on the daily dose exposure time (15-90 s at an irradiation rate of 20mW/cm 2 UV-B and A and of 14mW/cm 2 UV-C) and the duration of treatment (1-6 weeks). Ultimate load, tensile strength and modulus of elasticity showed an increase following medium dosages after 1 and 2 weeks, however, a decrease after high dosages and longterm treatment. Ultimate strain was found to be the most sensitive parameter being decreased depending on exposure time and duration of treatment. Insoluble collagen and total collagen were decreased after long-term treatment thus being correlated with the mechanical parameters. The elastin content was only barely influenced and not correlated with the mechanical data, e.g. the modulus of elasticity. Thus, a favourable effect of short-treatment with low doses of UV-irradiation of mechanical parameters of skin could be demonstrated. Long-term treatment with relatively high doses of UV-B, however, resulted in unfavourable effects, whereby first ultimate strain, then ultimate load, modulus of elasticity and tensile strength were decreased. (orig.) [de

Single high-dose irradiation aggravates eosinophil-mediated fibrosis through IL-33 secreted from impaired vessels in the skin compared to fractionated irradiation

International Nuclear Information System (INIS)

Lee, Eun-Jung; Kim, Jun Won; Yoo, Hyun; Kwak, Woori; Choi, Won Hoon; Cho, Seoae; Choi, Yu Jeong; Lee, Yoon-Jin; Cho, Jaeho

2015-01-01

We have revealed in a porcine skin injury model that eosinophil recruitment was dose-dependently enhanced by a single high-dose irradiation. In this study, we investigated the underlying mechanism of eosinophil-associated skin fibrosis and the effect of high-dose-per-fraction radiation. The dorsal skin of a mini-pig was divided into two sections containing 4-cm 2 fields that were irradiated with 30 Gy in a single fraction or 5 fractions and biopsied regularly over 14 weeks. Eosinophil-related Th2 cytokines such as interleukin (IL)-4, IL-5, and C–C motif chemokine-11 (CCL11/eotaxin) were evaluated by quantitative real-time PCR. RNA-sequencing using 30 Gy-irradiated mouse skin and functional assays in a co-culture system of THP-1 and irradiated-human umbilical vein endothelial cells (HUVECs) were performed to investigate the mechanism of eosinophil-mediated radiation fibrosis. Single high-dose-per-fraction irradiation caused pronounced eosinophil accumulation, increased profibrotic factors collagen and transforming growth factor-β, enhanced production of eosinophil-related cytokines including IL-4, IL-5, CCL11, IL-13, and IL-33, and reduced vessels compared with 5-fraction irradiation. IL-33 notably increased in pig and mouse skin vessels after single high-dose irradiation of 30 Gy, as well as in irradiated HUVECs following 12 Gy. Blocking IL-33 suppressed the migration ability of THP-1 cells and cytokine secretion in a co-culture system of THP-1 cells and irradiated HUVECs. Hence, high-dose-per-fraction irradiation appears to enhance eosinophil-mediated fibrotic responses, and IL-33 may be a key molecule operating in eosinophil-mediated fibrosis in high-dose-per fraction irradiated skin. - Highlights: • Single high-dose irradiation aggravates eosinophil-mediated fibrosis through IL-33. • Vascular endothelial cells damaged by high-dose radiation secrete IL-33. • Blocking IL-33 suppressed migration of inflammatory cells and cytokine secretion. • IL-33

Single high-dose irradiation aggravates eosinophil-mediated fibrosis through IL-33 secreted from impaired vessels in the skin compared to fractionated irradiation

Energy Technology Data Exchange (ETDEWEB)

Lee, Eun-Jung, E-mail: forejs2@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Kim, Jun Won, E-mail: JUNWON@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Yoo, Hyun, E-mail: gochunghee@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Kwak, Woori, E-mail: asleo02@snu.ac.kr [Interdisciplinary Program in Bioinformatics, Seoul National University, Seoul 151-747 (Korea, Republic of); Choi, Won Hoon, E-mail: wonhoon@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Cho, Seoae, E-mail: seoae@cnkgenomics.com [C& K Genomics, Seoul National University Mt.4-2, Main Bldg. #514, SNU Research Park, NakSeoungDae, Gwanakgu, Seoul 151-919 (Korea, Republic of); Choi, Yu Jeong, E-mail: yunk9275@daum.net [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Lee, Yoon-Jin, E-mail: yjlee8@kirams.re.kr [Division of Radiation Effects, Research Center for Radiotherapy, Korea Institute of Radiological & Medical Sciences, Seoul 139-760 (Korea, Republic of); Cho, Jaeho, E-mail: jjhmd@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of)

2015-08-14

We have revealed in a porcine skin injury model that eosinophil recruitment was dose-dependently enhanced by a single high-dose irradiation. In this study, we investigated the underlying mechanism of eosinophil-associated skin fibrosis and the effect of high-dose-per-fraction radiation. The dorsal skin of a mini-pig was divided into two sections containing 4-cm{sup 2} fields that were irradiated with 30 Gy in a single fraction or 5 fractions and biopsied regularly over 14 weeks. Eosinophil-related Th2 cytokines such as interleukin (IL)-4, IL-5, and C–C motif chemokine-11 (CCL11/eotaxin) were evaluated by quantitative real-time PCR. RNA-sequencing using 30 Gy-irradiated mouse skin and functional assays in a co-culture system of THP-1 and irradiated-human umbilical vein endothelial cells (HUVECs) were performed to investigate the mechanism of eosinophil-mediated radiation fibrosis. Single high-dose-per-fraction irradiation caused pronounced eosinophil accumulation, increased profibrotic factors collagen and transforming growth factor-β, enhanced production of eosinophil-related cytokines including IL-4, IL-5, CCL11, IL-13, and IL-33, and reduced vessels compared with 5-fraction irradiation. IL-33 notably increased in pig and mouse skin vessels after single high-dose irradiation of 30 Gy, as well as in irradiated HUVECs following 12 Gy. Blocking IL-33 suppressed the migration ability of THP-1 cells and cytokine secretion in a co-culture system of THP-1 cells and irradiated HUVECs. Hence, high-dose-per-fraction irradiation appears to enhance eosinophil-mediated fibrotic responses, and IL-33 may be a key molecule operating in eosinophil-mediated fibrosis in high-dose-per fraction irradiated skin. - Highlights: • Single high-dose irradiation aggravates eosinophil-mediated fibrosis through IL-33. • Vascular endothelial cells damaged by high-dose radiation secrete IL-33. • Blocking IL-33 suppressed migration of inflammatory cells and cytokine secretion. • IL

Preventive and Therapeutic Effects of Propolis in Gamma Irradiated Rats

International Nuclear Information System (INIS)

Hamza, R.G.; El-Shahat, A.N.

2011-01-01

Ionizing radiation is known to stimulate the generation of oxygen radicals which destabilize organic molecules resulting in a decrease of the system's antioxidant potential. Propolis (bee glue) is a complex mixture of natural substances that exhibits a broad spectrum of biological activities. As the possibility exists that it may exert a radio protections role, the present study aimed to examine the preventive and therapeutic effects of propolis on the gamma irradiation-induced changes in antioxidant status and certain biochemical parameters. HPLC chromatography for analysis of propolis showed that the number of identified phenols was 6 compounds (natural antioxidants). Male albino rats were exposed to 6 Gy of gamma radiation. The efficiency of propolis was evaluated when propolis was administered orally to rats at a dose of 200 mg/kg as follow: non-irradiated rats received orally propolis extract for 6 weeks (positive control) and rats received orally propolis extract for 3 weeks before or after gamma irradiation. The obtained results revealed that propolis given to rats before gamma irradiation protect the hazardous effects of gamma irradiation. In addition, administration of propolis to gamma irradiated rats caused significant enhancement in hepatic antioxidant enzymes (glutathion reductase; GR and catalase; CAT) and total antioxidant capacity associated with a remarkable decrease in the level of lipid peroxidation (TBARS). Also, it significantly reduced the changes induced by gamma irradiation in the serum levels of glucose and liver enzymes; aminotransferases (AST, ALT) and alkaline phosphatase (ALP). In addition, a significant improvement was observed in the serum levels of total cholesterol (TC), triglycerides (TG), low density lipoprotein- cholesterol (LDL-C) and high density lipoprotein-cholesterol (HDL-C). In conclusion, the positive results obtained in the gamma irradiated rats given propolis indicated that propolis could be considered as effective

Irradiated diets and its effect on testes and adrenal gland of rats

International Nuclear Information System (INIS)

Kushwaha, A.K.S.; Hasan, S.S.

1988-01-01

The present investigation was undertaken to study the feeding effects of irradiated normal diet (consisting of equal parts of gram and wheat) and irradiated low protein diet (consisting one part of normal diet and three parts of wheat) on male rats for various periods starting from weaning time. Rats maintained on irradiated low protein diets showed decrease in the activity of androgen sensitive enzymes i.e., alkaline and acid phosphatase while an increase in the cholesterol content of the testes compared with irradiated normal controls. Diminution in androgen sensitive enzymes and accumulation of cholesterol in the rat testes suggest non-conversion of cholesterol into steriod hormones after feeding of irradiated low protein. Besides, rats fed on irradiated low protein diet showed increased cellular activity in the adrenal cortex and medulla as compared to rats fed on the irradiated normal diet. (author). 12 refs., 4 tabs

Morphological studies on the healing process of tooth extraction wounds in whole body irradiated rats

International Nuclear Information System (INIS)

Hosokawa, Yoichiro

1991-01-01

The present studies were performed to investigate the healing process of the tooth extraction wound in whole body irradiated rats and to clarify the effect of irradiation on bone metabolism. One hundred and seven Wistar rats of about 100 g body weight were used and divided into 3 groups. Whole body irradiated rats were given single exposure with a dose of 8 Gy. The region of the left upper molars of local irradiated rats as controls, was exposed to 8 Gy. On the 7th day after irradiation, the left upper first molar of each rat was extracted. The rats were sacrificed at intervals of 1 to 14 days after extraction. Non-irradiated rats were sacrificed at the same intervals after extraction. The maxillary bone including the extraction wound was evaluated, histologically, histometrically and ultrastructurally. From the histological and histometrical findings, the difference of the healing process between non-irradiated rats and locally irradiated rats is not significant. In whole body irradiated rats, the healing process especially in the socket was disturbed. The osteoblastic new bone formation following production of granulation tissue was interfered with. Ultrastructurally, the cytoplasmic organellae were poorly developed in the osteoblast and osteoid formation was reduced in the socket. But periosteal new bone formation was the same as that of the locally irradiated rats. In whole body irradiated rats, the osteoclasts in the interradicular alveolar bone were decreased and have smaller nuclei, compared with non-irradiated and locally irradiated rats. Histometrically, the amount of bone loss was decreased in whole body irradiated rats. Ultrastructurally, the cyoplasmic organellae and ruffled border were poorly developed in the osteoclasts of whole body irradiated rats. The findings suggested that irradiation induced cytological changes not only in osteoblasts but in osteoclasts and these changes resulted in the delayed healing of extraction wound. (author) 106 refs

Morphological studies on the healing process of tooth extraction wounds in whole body irradiated rats

Energy Technology Data Exchange (ETDEWEB)

Hosokawa, Yoichiro (Hokkaido Univ., Sapporo (Japan). School of Dentistry)

1991-06-01

The present studies were performed to investigate the healing process of the tooth extraction wound in whole body irradiated rats and to clarify the effect of irradiation on bone metabolism. One hundred and seven Wistar rats of about 100 g body weight were used and divided into 3 groups. Whole body irradiated rats were given single exposure with a dose of 8 Gy. The region of the left upper molars of local irradiated rats as controls, was exposed to 8 Gy. On the 7th day after irradiation, the left upper first molar of each rat was extracted. The rats were sacrificed at intervals of 1 to 14 days after extraction. Non-irradiated rats were sacrificed at the same intervals after extraction. The maxillary bone including the extraction wound was evaluated, histologically, histometrically and ultrastructurally. From the histological and histometrical findings, the difference of the healing process between non-irradiated rats and locally irradiated rats is not significant. In whole body irradiated rats, the healing process especially in the socket was disturbed. The osteoblastic new bone formation following production of granulation tissue was interfered with. Ultrastructurally, the cytoplasmic organellae were poorly developed in the osteoblast and osteoid formation was reduced in the socket. But periosteal new bone formation was the same as that of the locally irradiated rats. In whole body irradiated rats, the osteoclasts in the interradicular alveolar bone were decreased and have smaller nuclei, compared with non-irradiated and locally irradiated rats. Histometrically, the amount of bone loss was decreased in whole body irradiated rats. Ultrastructurally, the cyoplasmic organellae and ruffled border were poorly developed in the osteoclasts of whole body irradiated rats. The findings suggested that irradiation induced cytological changes not only in osteoblasts but in osteoclasts and these changes resulted in the delayed healing of extraction wound. (author) 106 refs.

Intestinal metaplasia induced by x-irradiation in different strains of rats

International Nuclear Information System (INIS)

Watanabe, Hiromitsu; Naito, Masashi; Kawashima, Kengo; Ito, Akihiro

1985-01-01

Attempts were made to examine strain differences in the susceptibility of rats to intestinal metaplasia induced by X-irradiation. The gastric regions of 4 inbred male rats (SHR, F344, WKY, and LEW strains) in 5-week-old and 2 random bred male rats (SD, and WIS strains) were irradiated with a total dose of 20 Gy X-ray given in two equal fractions separated by three days. Upon sacrifice at 6 months after the last irradiation, the number of intestinal metaplastic crypts with positive reaction to alkaline phosphatase (ALP) appeared highest in the SHR and lowest in the WIS rats. Morphologically, the number of crypts with intestinal metaplasia in whole glandular stomachs of SHR, WIS, F344, and SD rats were higher than those in WKY and LEW rats. In the pyloric gland, it was highest in WIS rats, while in the fundic gland it was highest in SHR rats. The results show that the appearance and location of intestinal metaplasia by X-irradiation are greatly influenced by the strain of the rat. (author)

Studies on cutaneous lipid peroxide with special reference to the influences of ultraviolet irradiation

International Nuclear Information System (INIS)

Nomura, Kazuo

1981-01-01

The purpose of this study was to investigate the participation of lipid peroxide (LP) in some skin damages due to ultraviolet (UV) irradiation. Results obtained were as follows. 1) Long wave UV (UVA) was irradiated to rat skin homogenates. The levels of LP increased linearly with irradiation time. 2) When 8-methoxypsoralen was added to the homogenates prior to UVA irradiation, however, the LP levels showed no increase. 3) Various anti-oxidative agents were added to homogenates and UVA was irradiated. Only Vit. E reduced the LP levels in proportion to its concentrations. 4) Anti-oxidative agents were given to rats which were then exposed to PUVA (8-methoxypsoralen plus UVA) treatment. Among them, administration of Vit. E and pantethine was associated with reduction of serum and cutaneous LP levels with only slight histologic changes in the involved skin. 5) Vit. E deficient rats were treated with PUVA. In these models, cutaneous LP levels raised from 24 hours to 96 hours after PUVA treatment and histologic changes such as vacuolization, blister formation and cell degeneration were remarkable. From the above data, it became evident that lipid peroxidation took place in skin tissue per se and even in the UVA wave length region. After PUVA treatment, cutaneous LP levels relatively well correlated with histologic changes of the involved skin. The results suggested that LP played a certain role in skin damages due to UV. (author)

Effect of Bifidobacterium breve B-3 on skin photoaging induced by chronic UV irradiation in mice.

Science.gov (United States)

Satoh, T; Murata, M; Iwabuchi, N; Odamaki, T; Wakabayashi, H; Yamauchi, K; Abe, F; Xiao, J Z

2015-01-01

Probiotics have been shown to have a preventative effect on skin photoaging induced by short term UV irradiation, however, the underlying mechanisms and the effect of probiotics on skin photoaging induced by chronic UV irradiation remain unclear. In this study, we investigated the effect of Bifidobacterium breve B-3 on skin photoaging induced by chronic UV irradiation in hairless mice. Mice were irradiated with UVB three times weekly and orally administered B. breve B-3 (2×10(9) cfu/mouse /day) for 7 weeks. Nonirradiated mice and UVB-irradiated mice without probiotic treatment were used as controls. B. breve B-3 significantly suppressed the changes of transepidermal water loss, skin hydration, epidermal thickening and attenuated the damage to the tight junction structure and basement membrane induced by chronic UVB irradiation. Administration of B. breve B-3 tended to suppress the UV-induced interleukin-1β production in skin (P=0.09). These results suggest that B. breve B-3 could potentially be used to prevent photoaging induced by chronic UV irradiation.

Persistent and late occurring lesions in irradiated feet of rats: their clinical relevance

International Nuclear Information System (INIS)

Hopewell, J.W.

1982-01-01

Radiation-induced deformity, as characterized by tissue loss, has been investigated in rat feet. The acute epithelial response and the loss of deeper tissues occur concomitantly after irradiation. The greatest loss of tissue (severe deformity) was produced in feet where the healing of the epithelial reaction was greatly delayed. While deformity will clearly continue to ''persist'' after the acute reaction has healed it is misleading to refer to this lesion as ''late'' damage. A late-occurring lesion, not previously described in the literature, can be produced in the rat foot by high doses of radiation delivered in such a way that moist desquamation is avoided, i.e. by extending the total treatment time. Parallels are drawn between reactions in rodents and those in the skin of pig and man. (author)

The response of previously irradiated mouse skin to heat alone or combined with irradiation: influence of thermotolerance

NARCIS (Netherlands)

Wondergem, J.; Haveman, J.

1983-01-01

The skin of the mouse foot was used to study the effects of previous irradiation on the response to hyperthermia (44 degrees C), to irradiation, or to irradiation combined with hyperthermia (43 degrees C or 44 degrees C). Hyperthermia was applied by immersing the mouse foot into a hot waterbath and

Lupine Alleviate Hyperglycemia in Streptozotocin Diabetic gamma- Irradiated Rats

International Nuclear Information System (INIS)

El-Sayed, S.M.

2010-01-01

This study was to examine the regulatory effect of lupine on the diabetic profile developed in Streptozotocin (STZ) induced diabetic albino rats. The effectiveness of lupine against diabetes in gamma irradiated rats was purposed in the present study. Rats were received lupine seeds powder suspension (1 g/kg body weight for 14 consecutive days) before whole body exposure to 8 Gy of gamma radiation and /or STZ (55 mg/kg body weight, single dose) injection. The results pointed out that radiation exposure sustained the diabetic profile in rats received STZ comparing with STZ diabetic not irradiated rats. The prolonged administration of lupine suspension before STZ induction of diabetic and/or irradiated rats reduced the changes in the level of blood glucose, insulin concentration, liver glycogen, and the activity of glucose-6-phosphatase associated with significant amelioration in blood antioxidant status (superoxide dismutase, SOD; catalase, CAT; glucose-6-phosphate dehydrogenase, G-6-PD activities and reduced glutathione concentration GSH). Also, the level of blood lipid peroxides (TBARS) were reduced greatly when compared with its matched value in diabetic and /or gamma irradiated rats. It could be postulated that lupine powder suspension might be attenuate the diabetic profile development throughout reducing oxidative damages and modulating the antioxidant status. In addition, lupine could be considered as one of a remarkable radio protective agent owing to its antioxidants property

Electron-irradiation-induced phase transformation in alumina

International Nuclear Information System (INIS)

Chen, C.L.; Arakawa, K.; Lee, J.-G.; Mori, H.

2010-01-01

In this study, electron-irradiation-induced phase transformations between alumina polymorphs were investigated by high-resolution transmission electron microscopy. It was found that the electron-irradiation-induced α → κ' phase transformation occurred in the alumina under 100 keV electron irradiation. It is likely that the knock-on collision between incident electrons and Al 3+ cations is responsible for the occurrence of electron-irradiation-induced phase transformation from α-alumina to κ'-alumina.

Neutron irradiation of rat embryos in utero

International Nuclear Information System (INIS)

Vogel, H.H. Jr.

1978-01-01

In the rat radiation is most effective in producing congenital anomalies during the organ-forming period (days 9 to 13), which is approximately equivalent to the 14th to 50th days of human pregnancy. We have exposed female Sprague--Dawley rats on the 18th day of pregnancy to single whole-body doses of fission neutrons (20 to 150 rads). After 20 rads there was a small decrease in body weight which lasted from birth to weaning. During this period 9% of the irradiated rats died compared with 4% of the controls. After 50 rads, 65/275 (23.6%) of the rats died between birth and weaning, and the body-weight loss of the survivors was increased. After 100 rads, 62/133 (47%) died at birth or day 1 and 103/133 (77.4%) died before weaning. A large and significant decrease in body weight persisted in the survivors. After 150 rads of fission neutrons, all 95 rats died within 48 hr of birth. From cross-fostering experiments, we believe this is a direct effect of radiation on the embryos and not an indirect action through the mother or her milk. The LD 50 for the period from birth to weaning is approximately 75 rads of fission neutrons. Studies of organ weight were conducted daily for the first week after birth in an attempt to find the cause of radiation mortality. Body weight of the irradiated animals averaged only about one-half that of the controls. The liver, kidney, brain, and testes of the neutron-irradiated rats weighed significantly less than those of the controls. The weights of the spleen, lungs, duodenum, and stomach were decreased but not significantly. The bone marrow appeared depleted in the irradiated long bones, but the spleen maintained active hematopoiesis 1 to 2 months after neutron exposure

Neuronal damage in chick and rat embryos following X-irradiation

International Nuclear Information System (INIS)

Schneider, B.F.; Norton, S.

1980-01-01

Exposure of rat and chick embryos to X-irradiation at the time of development of neurons at the telencephalic-diencephalic border results in prolonged damage to neurons in this area as measured by neuronal nuclear size. A dose of 100 rads to the seven-day-old chick embryo has about the same effect as 125 rads to the 15-day-old rat fetus. The nuclear volume of large, multipolar neurons in the chick paleostriatum primitivum and the rat lateral preoptic area are reduced from 10 to 15%. Larger doses of X-irradiation to the chick (150 and 200 rads) cause progressively greater reductions in nuclear size. The large neurons which were measured in the rat and chick are morphologically similar in the two species. Both contain cytoplasmic acetylcholinesterase and have several branched, spiny dendritic processes. The similarity of response of chick and rat neurons to X-irradiation diminishes the significance of maternal factors as the cause of the effects of fetal irradiation in these experiments

Vitamin E-deficiency did not exacerbate partial skin reactions in mice locally irradiated with X-rays

International Nuclear Information System (INIS)

Chi, C.; Hayashi, Daisuke; Nemoto, Masato; Nyui, Minako; Anzai, Kazunori; Urano, Shiro

2011-01-01

We previously showed that free radicals and oxidative stress are involved in radiation-induced skin reactions. Since vitamin E (VE) is a particularly important lipophilic antioxidant, VE-deficient mice were used to examine its effects on radiation-induced skin damage. The VE content of the skin was reduced to one fourth of levels of normal mice. Neither the time of onset nor the extent of the reactions quantified with a scoring system differed between normal and VE-deficient mice after local X-irradiation (50 Gy). Similarly, there was no difference in the levels of the ascorbyl radical between the groups, although they were higher in irradiated skin than non-irradiated skin. X-irradiation increased the amount of Bax protein in the skin of normal mice both in the latent and acute inflammatory stages, time- and dose-dependently. The increase was associated with an increase in cytochrome c in the cytosolic fraction, indicating that apoptosis was also promoted by the irradiation. The increase in Bax protein correlated well with the thickness of the skin. Although a deficiency in VE should lower resistance to free radicals in the mitochondrial membrane and thus enhance radiation-induced Bax expression and apoptosis, it actually attenuated the increase in Bax protein caused by irradiation. (author)

Frequency of polyploid cells in the bone marrow of rats fed irradiated wheat

International Nuclear Information System (INIS)

George, K.P.; Chaubey, R.C.; Sundaram, K.; Gopal-Ayengar, A.R.

1976-01-01

Diets containing different proportions of non-irradiated or irradiated wheat were fed to Wistar rats for 1 or 6 wk. Cytological analysis of the bone marrow showed no significant difference in the frequency of polyploid cells in the rats fed non-irradiated or irradiated wheat diets, even when the treated wheat was fed to the rats within 24 hr of irradiation. (author)

Serum metabonomics of rats irradiated by low-dose γ-rays

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Ying HE

2014-08-01

Full Text Available Objective　To explore the effect of low-dose γ-rays on the metabolites in rat serum. Methods　Sixteen healthy male SD rats were randomly divided into control group and irradiated group (n=8. The rats in irradiated group were irradiated by 60Co γ-rays with a dose rate of 72mGy/h for 7 days (1 hour per day. At the 7th day after irradiation, blood samples were taken from abdominal aorta to obtain the serum. The metabolic fingerprints of serum were obtained from the two groups of rats, and 1H nuclear magnetic resonance (NMR spectroscopy, principal component analysis (PCA and orthogonal signal correction-partial least squares (OSC-PLS method were used for pattern recognition, and the difference in metabolite profile between two groups was identified by SIMCA-P software. Results　The rat serum 1H NMR spectra revealed a significant difference between control group and irradiated group, the OSC-PLS plots of the serum samples presented marked clustering between two groups. Compared with the control group, the content of lipid, glucose, creatine, glycine/glucose, high density lipoprotein, low density lipoprotein, very low density lipoprotein/low density lipoprotein and unsaturated fatty acid increased, while the content of lactic acid, threonine/lipid, alanine, N-acetyl glycoprotein 1, N-acetyl glycoprotein 2, saturated fatty acid and phosphatidyl choline decreased in irradiated group. Conclusion　Irradiation with low-dose γ-ray could induce changes in metabolites in rat serum, concerning mainly immune function, energy metabolism, carbohydrate metabolism and lipid metabolism. DOI: 10.11855/j.issn.0577-7402.2014.07.02

Go/no-go discriminated avoidance learning in prenatally x-irradiated rats

International Nuclear Information System (INIS)

Tamaki, Y.; Inouye, M.

1988-01-01

Male Fischer344 rats were exposed to x-irradiation at a dose of 200 rad on Day 17 of gestation. Irradiated and control rats were tested at 10-13 weeks of age with the paradigm of go/no-go (active-passive) discriminated avoidance conditioning for three consecutive daily sessions. During the first conditioning session, they learned only active avoidance responses to two different warning signals. During the second and third sessions, they learned active and passive avoidance responses: in response to one warning signal, rats were required to make an active response to avoid a shock, but not to run in response to the other signal in order to avoid a shock. Prenatally irradiated rats made more active avoidance responses to both warning signals than controls (first session). In the early training phase of the go/no-go task, irradiated rats performed significantly higher active and lower passive avoidance responses than controls. Irradiated rats established a strong tendency to respond actively to the no-go signal, but eventually learned to respond to it

Percutaneous penetration of 2-phenoxyethanol through rat and human skin.

Science.gov (United States)

Roper, C S; Howes, D; Blain, P G; Williams, F M

1997-01-01

2-Phenoxyethanol applied in methanol was absorbed (64 +/- 4.4% at 24 hr) through unoccluded rat skin in vitro in the static diffusion cell with ethanol/water as receptor fluid. By comparison (43 +/- 3.7% in 24 hr) was absorbed in the flow-through diffusion system with tissue culture medium as receptor fluid. 2-Phenoxyethanol applied in methanol was absorbed (59.3 +/- 7.0% at 6 hr) through unoccluded human skin in vitro in the flow-through diffusion cell with tissue culture medium. With both unoccluded cells, 2-phenoxyethanol was lost by evaporation but occlusion of the static cell reduced evaporation and increased total absorption to 98.8 +/- 7.0%. Skin, post mitochondrial fraction, metabolized phenoxyethanol to phenoxyacetic acid at 5% of the rate for liver. Metabolism was inhibited by 1 mM pyrazole, suggesting involvement of alcohol dehydrogenase. However, first-pass metabolism of phenoxyethanol to phenoxyacetic acid was not detected during percutaneous penetration through viable rat skin in the flow-through system. First-pass metabolism in the skin does not therefore have an influence on systemic availability of dermally absorbed phenoxyethanol. These measures of phenoxyethanol absorption through rat and human skin in vitro agree well with those obtained previously in vivo.

The radiation response of skin in young and old rats

International Nuclear Information System (INIS)

Hamlet, R.; Hopewell, J.W.

1982-01-01

The results of this investigation clearly demonstrate the different radiation skin response in rats of differing ages. The reasons for these differences cannot be clarified until cell kinetic studies have been completed. These results obtained for rodent skin would appear to be in disagreement with the available data for human skin (Rubin and Casarett 1968) where no marked age-related changes were reported. Also, in pig skin studies (Hopewell and Young 1982) there was no evidence of an age effect in the dermal vascular response in 3-12-month-old animals. This may be related to the different tissue being investigated or it may reflect important species differences. Whatever the reasons behind these observations, the different skin response to radiation in rats of 7, 14 and 52 weeks of age has clearly been demonstrated and should be borne in mind when extrapolating data with rodent skin to the clinical situation. (author)

Gluconeogenesis in lethally X-irradiated rats

International Nuclear Information System (INIS)

Paulikova, E.; Ahlers, I.; Praslicka, M.

1983-01-01

The in vivo incorporation of U- 14 C-alanine into blood glucose and liver glycogen was measured in rats irradiated with a single whole body lethal dose of X-rays. Changes in gluconeogenic enzyme activities were studied in the liver. Increased incorporation of 14 C-alanine into blood glucose and liver glycogen were found after irradiation. Liver phosphoenolpyruvate carboxykinase and glycogenic activity underwent almost parallel changes and were significantly elevated from the 6th to the 48th hour, with resultant accumulation of glycogen. Glucose-6-phosphatase activity was depressed and there was a negative correlation between it and liver glycogen concentration. Maximum fructose-1,6-diphosphatase activity was found at 48 hours. The results show that glycogen accumulation in the liver and the raised blood glucose level in X-irradiated rats are based on raised gluconeogenesis. (author)

Gluconeogenesis in lethally X-irradiated rats

Energy Technology Data Exchange (ETDEWEB)

Paulikova, E.; Ahlers, I.; Praslicka, M. (Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie)

1983-02-01

The in vivo incorporation of U-/sup 14/C-alanine into blood glucose and liver glycogen was measured in rats irradiated with a single whole body lethal dose of X-rays. Changes in gluconeogenic enzyme activities were studied in the liver. Increased incorporation of /sup 14/C-alanine into blood glucose and liver glycogen were found after irradiation. Liver phosphoenolpyruvate carboxykinase and glycogenic activity underwent almost parallel changes and were significantly elevated from the 6th to the 48th hour, with resultant accumulation of glycogen. Glucose-6-phosphatase activity was depressed and there was a negative correlation between it and liver glycogen concentration. Maximum fructose-1,6-diphosphatase activity was found at 48 hours. The results show that glycogen accumulation in the liver and the raised blood glucose level in X-irradiated rats are based on raised gluconeogenesis.

Solar ultraviolet irradiation induces decorin degradation in human skin likely via neutrophil elastase.

Science.gov (United States)

Li, Yong; Xia, Wei; Liu, Ying; Remmer, Henriette A; Voorhees, John; Fisher, Gary J

2013-01-01

Exposure of human skin to solar ultraviolet (UV) irradiation induces matrix metalloproteinase-1 (MMP-1) activity, which degrades type I collagen fibrils. Type I collagen is the most abundant protein in skin and constitutes the majority of skin connective tissue (dermis). Degradation of collagen fibrils impairs the structure and function of skin that characterize skin aging. Decorin is the predominant proteoglycan in human dermis. In model systems, decorin binds to and protects type I collagen fibrils from proteolytic degradation by enzymes such as MMP-1. Little is known regarding alterations of decorin in response to UV irradiation. We found that solar-simulated UV irradiation of human skin in vivo stimulated substantial decorin degradation, with kinetics similar to infiltration of polymorphonuclear (PMN) cells. Proteases that were released from isolated PMN cells degraded decorin in vitro. A highly selective inhibitor of neutrophil elastase blocked decorin breakdown by proteases released from PMN cells. Furthermore, purified neutrophil elastase cleaved decorin in vitro and generated fragments with similar molecular weights as those resulting from protease activity released from PMN cells, and as observed in UV-irradiated human skin. Cleavage of decorin by neutrophil elastase significantly augmented fragmentation of type I collagen fibrils by MMP-1. Taken together, these data indicate that PMN cell proteases, especially neutrophil elastase, degrade decorin, and this degradation renders collagen fibrils more susceptible to MMP-1 cleavage. These data identify decorin degradation and neutrophil elastase as potential therapeutic targets for mitigating sun exposure-induced collagen fibril degradation in human skin.

Validation and dosimetric evaluation employing the techniques of TL and OSL of thermoluminescent materials for application in the dosimetry of clinical beams of electrons used in total irradiation of the skin - TSI

International Nuclear Information System (INIS)

Almeida, Shirlane Barbosa de

2017-01-01

In vivo dosimetry has become an important role for the treatment of total skin irradiation within a rigorous quality assurance program that should be an integral part of the radiotherapy departments. TSI dosimetry is difficult because of the complexity of the treatment in assessing dose uniformity and measuring the dose absorbed at shallow depths throughout the skin surface extent, resulting in a wide variation in dose distribution. The TLDs have proven to be very useful for the distribution and verification of the dose prescribed for the patient as the dose may differ from place to place due to patient body geometry, overlapping of structures and asymmetries of the radiation field. The use of TLDs in vivo can identify variations in the prescribed dose because its measurement accuracy and great precision. Several types of dosimeters have been used in the radiotherapy sectors, the most commonly used are Lithium Fluride (TLD-100), where it obtains a long history in this type of application. New dosimetric materials have gained great importance in the dosimetry of clinical electron beams, such as Dysprosium-doped Calcium Sulphate (TL) and Carbon doped (OSL) based Aluminum Oxide, This work evaluates the performance of the respective thermoluminescent dosimeters and the optically stimulated luminescence in the dosimetry of clinical electron beams used in total irradiation of the skin. (author)

Comparison of atmospheric microplasma and plasma jet irradiation for increasing of skin permeability

International Nuclear Information System (INIS)

Shimizu, K; Tran, N A; Hayashida, K; Blajan, M

2016-01-01

Atmospheric plasma is attracting interest for medical applications such as sterilization, treatment of cancer cells and blood coagulation. Application of atmospheric plasma in dermatology has potential as a novel tool for wound healing, skin rejuvenation and treatment of wrinkles. In this study, we investigated the enhancement of percutaneous absorption of dye as alternative agents of transdermal drugs. Hypodermic needles are often the only way to deliver large-molecule drugs into the dermis, although a safe transdermal drug delivery method that does not require needles would be desirable. We therefore explored the feasibility of using atmospheric microplasma irradiation to enhance percutaneous absorption of drugs, as an alternative delivery method to conventional hypodermic needles. Pig skin was used as a biological sample, exposed to atmospheric microplasma, and analyzed by attenuated total reflection-Fourier transform infrared spectroscopy. A tape stripping test, a representative method for evaluating skin barrier performance, was also conducted for comparison. Transepidermal water loss (TEWL) was measured and compared with and without atmospheric microplasma irradiation, to quantify water evaporation from the inner body through the skin barrier. The results show that the stratum corneum, the outermost skin layer, could be chemically and physically modified by atmospheric microplasma irradiation. Physical damage to the skin by microplasma irradiation and an atmospheric plasma jet was also assessed by observing the skin surface. The results suggest that atmospheric microplasma has the potential to enhance percutaneous absorption. (paper)

Evolution of glycaemia in the rat after gamma irradiation; Evolution de la glycemie chez le rat apres irradiation gamma

Energy Technology Data Exchange (ETDEWEB)

Marble, G; Frossard, H; Breuil, L; Engler, R [Commissariat a l' Energie Atomique, Fontenay aux Roses (France). Centre d' Etudes Nucleaires

1965-07-01

The study of glycaemia variations in the rat after irradiation has made it possible to observe not only a premature hyperglycemia but also a belated hypoglycemia whose importance and subsequent evolution seem to depend on the dose given to the animal. (authors) [French] L'etude des variations de la glycemie du rat apres irradiation a permis de noter une hyperglycemie precoce mais egalement une hypoglycemie retardee dont l'amplitude et l'evolution seraient fonction de la dose delivree a l'animal. (auteurs)

The expression changes of inflammatory cytokines in the hippocampus following whole-brain irradiation in rats

International Nuclear Information System (INIS)

Yu De; Tian Ye; Ding Weijun; Zhu Yaqun; Liu Chunfeng

2004-01-01

To investigate the change pattern of some inflammatory cytokines in brain tissue at the acute phase after brain irradiated. The whole brain of SD rats was irradiated by the single dose of 2, 15 or 30 Gy of 4 MeV electron beam. The enzyme-linked immunosorbent assay (ELISA) was used for the measurement of IL-1 β, IL-6, and TNF-α content in hippocampus tissue of rats at 1h, 6h, 12h, 1d, 2 and 1 week post-irradiation. The mRNA of IL-1 β, IL-6, and TNF-α were detected by reverse-transcription polymerase chain reaction (RT-PCR) in the same experimental groups. It was analyzed about the influence of dosage and post-irradiation duration with the cytokines expression. Compared with both the normal control and the anesthetized with chloral hydrate but sham-irradiation groups, there were no difference about the three inflammatory cytokines expression in rats with 2 Gy irradiated. At 6h after irradiation with 15 Gy, 6 and 12h with 30 Gy groups, the content of IL-1β and TNF-α in hippocampus tissue were significantly increased, and were returned to normal level after 12 to 24h. The same change tendency of their mRNA relational level was observed in 15 and 30 Gy groups, but it happened earlier in 1h after exposure. Although the content of IL-6 in hippocampus kept stable in all the groups, its mRNA level raised obviously in 12h group. After 15-30 Gy whole-brain irradiation, the expression of some inflammatory cytokines increased abruptly in the hippocampus of SD rat within 1 day, but the interplay between inflammatory cytokines changes and the pathogenesis of radiation injury was incompletely understood at present. (authors)

Late nonstochastic changes in pig skin after β irradiation

International Nuclear Information System (INIS)

Peel, D.M.; Hopewell, J.W.; Wells, J.; Charles, M.W.

1985-01-01

Late radiation-induced changes in pig skin have been assessed following irradiation with β-rays from a 22.5- or 15-mm-diameter 90 Sr/ 90 Y source and a 19- or 9-mm-diameter 170 Tm source. Late damage, in terms of dermal atrophy, was assessed 2 years after irradiation from measurements of dermal thickness of 40-50% of the control value, occurred at a dose of approx. 40 Gy from the 22.5-mm source and approx. 75 Gy from the 15-mm source. In the case of 170 Tm the 19- and 9-mm sources produced similar degrees of atrophy at equal doses. Maximum atrophy occurred at approx. 70 Gy, when the dermis was approx. 70% of the thickness of normal skin. Significant late tissue atrophy was seen at doses, from both types of radiation, which only produced minimal erythema in the early reaction. Such late reactions need to be taken into account when revised radiological protection criteria are proposed for skin

Preliminary study of the irradiation-induced modification of skin permeability

International Nuclear Information System (INIS)

Coelho, R.; Istin, M.

1978-01-01

Irradiation of the skin of an animal leads immediately to a strong increase in vascular permeability. If a dye is at once injected intraveinously it diffuses very rapidly in the irradiated zone, this becomes highly coloured and the colour intensity measurement gives a clue to the severity of the lesions produced. This phenomenon has been used in the past as a pharmacological test to study vascular permeability and is employed in this work to observe the effect of diosmine-titrated flavonoids on vascular permeability in inflammatory diseases. The capillary permeability increase due to local γ irradiation of rabbit skin has been accurately determined by measurement of the colouration observed after injection of Geigy Blue. Diosmine, injected intraperitoneally, protects the vascular system against increased permeability due to ionising radiations [fr

Early ultrastructural changes in the dorsal mucosa of rat tongue after irradiation, with special reference to the microvasculature

International Nuclear Information System (INIS)

Obinata, Ken-ichi; Ohshima, Hayato; Ito, Jusuke; Takano, Yoshiro.

1997-01-01

To clarify the acute effects of irradiation on the ultrastructural conformation of the dorsal mucosa of the rat tongue, with special reference to the changes in microvasculature. The proboscis of seventy rats were irradiated. The animals were then perfusion-fixed, followed by India ink-injection or resin casting at 3 to 7 days after irradiation. The bulk, frozen sections, or plastic embedded sections of the treated rat tongues were examined by light and electron microscopy. In the dorsal epithelium of the rat tongue, multi-nucleated cells appeared in the basal layer at 3 days after irradiation. At day 5, the thickness of the epithelial layer and connective tissue papillae decreased dramatically, concomitant with the shortening of the capillary loops. At day 7, lingual papillae and connective tissue papillae disappeared, leaving dissociated epithelial cells and numerous neutrophils migrating throughout the tissue. Subepithelial blood vessels displayed drastic dilation with a number of neutrophils adhering to the endothelial surface, but without ultrastructural abnormalities in its cellular components. Early changes in the dorsal mucosa of the irradiated rat tongue were limited to the basal epithelial cells, leading to a total disruption of the epithelial layer. Atrophic changes of the capillary loops is due to the loss of the connective tissue papillae. Dilation and conformational changes of the subepithelial capillaries appear to result from the inflammatory reaction, taking place secondarily to the loss of the epithelial barrier of the irradiated tongue. A difference in radiosensitivity among the epithelial, endothelial, and mesenchymal cell components of the rat tongue in vivo is suggested. (author)

Radioprotective effects of aronia on radiation irradiated rats

Energy Technology Data Exchange (ETDEWEB)

Mun, Hwan Sik; Lee, Jun Haeng [Dept. of Radiology, Nambu University, Gwangju (Korea, Republic of)

2017-09-15

The present study was intended to orally administer aronia to rats, irradiate radiation once to the whole bodies of the rats, and conduct blood tests to observe, compare, and analyze changes in blood cells, such as leukocytes, erythrocytes, and platelets, in order to examine the radioprotective effects of aronia. As experimental animals, 15 male Sprague-Dawley (SD) rats aged six weeks weighing 200∼250 g were taken and divided into the normal group (A) of five rats, the 5 Gy control group (B) of five rats, and the 5 Gy experimental group (C) of five rats. The normal group (A) was not irradiated at all, the control group (B) was administered with general diets and irradiated, and the experimental group(C) was orally administered with 50 mg/kg/day of aronia two times per day to achieve a distilled water oral dose of 100 mg/kg/day and irradiated thereafter (5 Gy at 500 cGy/min) for 14 days. After the experiment, differences in leukocytes, erythrocytes, and platelets among the normal group (A), the control group (B), and the experimental group (C) were examined by comparing the counts of the blood cells and the results showed no statistically significant differences. However, on a detailed review, the normal group (A) showed statistically higher mean values for all of lymphocytes, hemoglobin, and mean corpuscular hemoglobin as compared to the control group (B) and the experimental group (C). Statistically significant differences in the counts of lymphocytes were shown between the normal group (A) and the control group (B), and between the normal group (A) and the experimental group (C); furthermore, statistically significant differences in mean corpuscular hemoglobin were shown between the normal group (A) and the experimental group (C). Given the results of the present study, in irradiated rats, aronia was generally considered as having no radioprotective effect on leukocyte, erythrocyte, and platelet while having statistically significant radioprotective effects on

Characterization of ionizing radiation effects on human skin allografts

International Nuclear Information System (INIS)

Bourroul, Selma Cecilia

2004-01-01

The skin has a fundamental role in the viability of the human body. In the cases of extensive wounds, allograft skin provides an alternative to cover temporarily the damaged areas. After donor screening and preservation in glycerol (above 85%), the skin can be stored in the Skin Banks. The glycerol at this concentration has a bacteriostatic effect after certain time of preservation. On the other hand, skin sterilization by ionizing radiation may reduces the quarantine period for transplantation in patients and its safety is considered excellent. The objectives of this work were to establish procedures using two sources of ionizing radiation for sterilization of human skin allograft, and to evaluate the skin after gamma and electron beam irradiation. The analysis of stress-strain intended to verify possible effects of the radiation on the structure of preserved grafts. Skin samples were submitted to doses of 25 kGy and 50 kGy in an irradiator of 60 Co and in an electron beam accelerator. Morphology and ultra-structure studies were also accomplished. The samples irradiated with a dose of 25 kGy seemed to maintain the bio mechanic characteristics. The gamma irradiated samples with a dose of 50 kGy and submitted to an electron beam at doses of 25 kGy and 50 kGy presented significant differences in the values of the elasticity modulus, in relation to the control. The analysis of the ultramicrographies revealed modifications in the structure and alterations in the pattern of collagen fibrils periodicity of the irradiated samples. (author)

Effect of irradiation on the periodontal tissues in streptozotocin-induced diabetic rats

International Nuclear Information System (INIS)

Park, Dong Sin; Hwang, Eui Hwan; Lee, Sang Rae

2005-01-01

To observe the histopathological changes in the periodontal tissues of mandibular molars in streptozotocin-induced diabetic rats after irradiation. The male Sprague-Dawley rats weighing approximately 250 gm were divided into four groups; control, diabetes, irradiation, and diabetes - irradiation groups. Diabetes mellitus was induced in the rats by injecting streptozotocin. Rats in the control and irradiation groups were injected with citrate buffer only. After 5 days, the head and neck region of the rats in irradiation and diabetes - irradiation groups were irradiated with a single absorbed dose of 10 Gy. All the rats were sacrificed at 3, 7, 14, 21, and 28 days after irradiation. The specimen including the mandibular molars were sectioned and observed using a histopathological method. In the diabetes group, osteoclastic activity was observed in the alveolar bone and the root throughout the period of experiment. Also, osteoblastic and fibroblastic activities were markedly decreased. In the irradiation group, the osteoclasts were observed in the alveolar bone and the dilated capillaries were increased in the early experimental phases. However, vigorous osteoblastic activity was noted in the late experimental phases. In the diabetes- irradiation group, osteoblastic activity in the alveolar bone and the root was observed in the early experimental phases. However, there were no resorption and osteoblastic activity in the alveolar bone and the root in the late experimental phases, and obvious atrophic change of fibrous tissues was noted. This experiment suggests that osteoblastic activity was caused by irradiation in the late experimental phases, but atrophic change of the periodontal ligament tissues was induced after irradiation in diabetic state.

The changes in pharmacokinetics and conjugation of chloramphenicol in irradiated rats

International Nuclear Information System (INIS)

Stoklasova, A.; Krizala, J.; Ledvina, M.

1978-01-01

In the serum and the liver of rats levels of chloramphenicol (CAP) following its i.v. administration (200mg/kg) in the control groups and in the rats irradiated with whole-body air exposure to 500 R were determined with spectrophotometric methods. The CAP-levels in the serum increased in the group of rats 3 days after irradiation, but only during the 1st hour. At later time intervals the values were lower than in the controls. This decrease at the 60th min is striking even in the groups 6 and 9 days after exposure. Free CAP in the liver of rats irradiated 6 and 9 days before was lower at interval 30min after CAP-administration, but the group irradiated 9 days before was unaltered. However, 120min after CAP-administration the values of free CAP decreased at all intervals investigated following the irradiation. The levels of conjugated CAP in the liver of the rats 3 and 6 days after exposure were lower than in controls in both intervals after drug administration; but in rats 9 days after irradiation they increased. Our results indicate that the kinetics of CAP is altered and corresponding changes in its conjugation are effected under the condition of acute radiation syndrome. (orig.) [de

Biological Mechanisms Underlying the Ultraviolet Radiation-Induced Formation of Skin Wrinkling and Sagging I: Reduced Skin Elasticity, Highly Associated with Enhanced Dermal Elastase Activity, Triggers Wrinkling and Sagging

Science.gov (United States)

Imokawa, Genji; Ishida, Koichi

2015-01-01

The repetitive exposure of skin to ultraviolet B (UVB) preferentially elicits wrinkling while ultraviolet A (UVA) predominantly elicits sagging. In chronically UVB or UVA-exposed rat skin there is a similar tortuous deformation of elastic fibers together with decreased skin elasticity, whose magnitudes are greater in UVB-exposed skin than in UVA-exposed skin. Comparison of skin elasticity with the activity of matrix metalloproteinases (MMPs) in the dermis of ovariectomized rats after UVB or UVA irradiation demonstrates that skin elasticity is more significantly decreased in ovariectomized rats than in sham-operated rats, which is accompanied by a reciprocal increase in elastase activity but not in the activities of collagenases I or IV. Clinical studies using animal skin and human facial skin demonstrated that topical treatment with a specific inhibitor or an inhibitory extract of skin fibroblast-derived elastase distinctly attenuates UVB and sunlight-induced formation of wrinkling. Our results strongly indicated that the upregulated activity of skin fibroblast-derived elastase plays a pivotal role in wrinkling and/or sagging of the skin via the impairment of elastic fiber configuration and the subsequent loss of skin elasticity. PMID:25856675

DNA repair in Bloom's syndrome skin fibroblasts after ultraviolet light irradiation

International Nuclear Information System (INIS)

Kurihara, Takayuki; Inoue, Masao; Kawashima, Hiroko; Yagi, Takashi; Takebe, Hiraku.

1981-01-01

Skin fibroblasts from a patient with Bloom's syndrome (86NoKi) were assayed for various DNA repair activities after ultraviolet light (UV) irradiation. Cultured fibroblasts as well as lymphocytes obtained from this patient showed a high frequency of spontaneous sister chromatid exchanges (SCEs). There was no significant difference between 86NoKi fibroblasts and skin fibroblasts from normal donors in the sensitivity to UV as measured by inactivation of colony forming activity, the capacity of host-cell reactivation (HCR) of UV-irradiated virus, and the amount of unscheduled DNA synthesis (UDS) after UV irradiation. However, the yield of UV-induced SCEs in 86NoKi cells was significantly higher than that in normal cells. (author)

Epinephrine as a metabolic regulatory hormone in irradiated rats

International Nuclear Information System (INIS)

Mohamed, M.A.; Saada, H.N.; Roushdy, H.M.; Awad, O.M.; El-Sayed, M.M.; Azab, Kh.Sh.

1997-01-01

The role of epinephrine as a regulatory hormone was examined in normal and irradiated rats. Epinephrine was intraperitoneally injected into rats at a concentration of 200 Mg/kg body weight. Epinephrine was injected either 15 minutes before or just after whole body gamma irradiation 6 Gy 9 single dose). The variations in serum epinephrine,norepinephrine, triglycerides,lipase activity, glucose and lactic acid were selected as biochemical markers in this study. Biochemical estimations were undertaken at 1 hr, 4 hrs. 1,3 and 7 days treatment (after irradiation). The data obtained revealed that the treatment of normal rats with epinephrine induced a significant increase in serum epinephrine level 1 hr after injection, while the level of norepinephrine significantly increased at 4 hrs. Lipase activity significantly increased on the 1 ST hr post treatment. A significant decrease in the level of triglycerides was recorded 1 and 4 hrs post treatment. Serum glucose significantly increased at 1 and 4 hrs post treatment, while no significant changes were recorded for lactic acid. In gamma irradiated rats, the level of serum epinephrine significantly decreased at 1 hr followed by significant increases recorded at 1,3, and 7 days after irradiation. Norepinephrine levels significantly decreased after irradiation during all the experimental time periods. The levels of triglycerides show significant increases accompanied by decrease in lipase activity

Variations in epidermal cytochrome oxidase activity after local irradiation

International Nuclear Information System (INIS)

Itoiz, M.E.; Rey, B.M. de; Cabrini, R.L.

1982-01-01

Cytochrome oxidase activity was evaluated histochemically as an index of mitochondrial damage after local irradiation with X-rays. It was determined by microphotometry on the tail skin of newly born Wistar rats four days after irradiation with doses ranging from 2 to 16krad. The enzyme activity of the whole epidermis increased after irradiation, the increases being related to the increase in thickness of the epithelium which was observed as a response to irradiation injury. Within the dose range tested, the enzyme concentration (expressed per unit volume of tissue) decreased in relation to the dose applied. At the electron microscopy level, the cytochemical demonstration of cytochrome oxidase revealed an irregular reaction over the cristae, intramitochondrial vacuolization and partial homogenization of the matrix. Positive membrane fragments were seen around lipid droplets. This reaction confirms the mitochondrial origin of these previously observed radiation-induced vacuoles. (author)

Metabolic changes after non-lethal X-irradiation of rats. I

International Nuclear Information System (INIS)

Ahlersova, E.; Ahlers, I.; Slavkovska, E.; Praslicka, M.

1981-01-01

Male rats of the Wistar strain were fasted overnight prior to exposure to single whole-body X-ray dose of 2.39 Gy (250 R). Irradiated and sham-irradiated rats were pair-fed for 5 days, in the following period they were fed ad libitum. The levels of corticosterone and immunoreactive insulin in serum, glucose in blood, glycogen in liver, heart and skeletal muscle were determined 1 and 6 h, 1, 2, 3, 7, 14, 21, 28, and 38 days after irradiation and sham-irradiation. Irradiation of rats resulted, in one hour, in a decrease and, in two days, in an increase in blood glucose level. A marked increase in liver glycogen persisted from 6 h to 21 days after irradiation. The level of glycogen in the skeletal muscle was reduced after 6 h and increased on days 3 and 14. Heart muscle glycogen declined within the first 24 h and rose at 14 days after exposure. The kinetics of changes in the heart and skeletal muscle glycogen following non-lethal irradiation was similar and indicated an overlap of changes produced by fasting with those brought about by irradiation, particularly during the first week. Corticosterone in serum was markedly increased in rats 24 and 72 h after irradiation compared to pair-fed controls. The serum insulin concentration did not change after irradiation, except for a single increase on day 21. Irradiation with non-lethal doses produced changes in the parameters of the carbohydrate metabolism studied, except for serum insulin which reflected the changes in the nutrition regimen upon pair-feeding rather than the effect of ionizing irradiation. (author)

Melatonin, a potential effective protector in whole body γ-irradiated rats

International Nuclear Information System (INIS)

Tawfik, S.S; El-Nashar, D.E; Ahmed, M.M; Hanafy, Z.E

2010-01-01

Melatonin (N-acetyl-5-methoxytryptamine), the chief hormone of pineal gland, is widely distributed in animal kingdom. It is claimed for its antioxidant and free radical properties. The present study aimed to examine the radio protective potentiality and efficacy of melatonin against damages induced in whole body γ-irradiated rats. Animals received melatonin (10 mg/ kg body wt/ day) for 10 successive days pre-exposure to 3 Gy of γ-radiation (acute dose). Rats sacrificed at 10 and 20 days post the irradiation time. The results revealed that the prolonged administration of melatonin has ameliorated the radiation- induced depletion in brain, testis and serum glutathione (GSH) level and a decrease in serum glutathione peroxidase (GPX) activity when compared with their matched values in irradiated rats. In addition, remarkable decreases in the concentration of lipid peroxidation (LPO) product; malondialdhyde (MDA) was observed in brain, testis and serum of rats received melatonin pre-radiation exposure. As well as, significant decreases in disulphide glutathione (GSSG) were observed in serum.Histopathological examination of brain and testis showed that administration of melatonin pre-irradiation according to the present regimen has attenuated radiation induced tissue damages and improved tissue architecture. Cytogenetically, the chromosomal aberration (CA) assay in bone marrow pointed out a significant difference between rats received melatonin pre-irradiation and γ-irradiated rats in most CA types. Accordingly, it could be postulated the tissue diversity and cytogenetic impact of the administrated melatonin against acute ion syndrome in rat model.

Effect of irradiation on the dental pulp tissues in streptozotocin-induced diabetic rats

International Nuclear Information System (INIS)

Kang, Ho Duk; Hwang, Eui Hwan; Lee, Sang Rae

2005-01-01

To observe the histological changes in the pulp tissues of mandibular molars in streptozotocin-induced diabetic rats after irradiation. The male Sprague-Dawley rats weighing approximately 250 gm were divided into four groups : control, diabetes, irradiation, and diabetes-irradiation groups. Diabetes mellitus was induced in the rats by injecting streptozotocin. Rats in control and irradiation groups were injected with citrate buffer only. After 5 days, the head and neck region of the rats in irradiation and diabetes-irradiation groups were irradiated with a single absorbed dose of 10 Gy. All the rats were sacrificed at 3, 7, 14, 21, and 28 days after irradiation. The specimen including the mandibular molars were sectioned and observed using a histopathological method. In the diabetes group, capillary dilatation was observed. However, there was no obvious morphologic alteration of the odontoblasts. In the irradiation group, generalized necrosis of the dental pulp tissues was observed. Vacuolation of the odontoblasts and dilatation of the capillaries were noted in the early experimental phases. In the diabetes-irradiation group, generalized degeneration of the dental pulp tissues was observed. Vacuolation of the dental pulp cells and the odontoblasts was noted in the late experimental phases. This experiment suggest that dilatation of the capillaries in the dental pulp tissue is induced by diabetic state, and generalized degeneration of the dental pulp tissues is induced by irradiation of the diabetic group.

Effect of irradiation on the healing of extraction sockets in diabetic rats

Energy Technology Data Exchange (ETDEWEB)

Kim, Il Joong; Hwang, Eui Hwan; Lee, Sang Rae [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

2003-03-15

To observe the histologic pattern of healing in molar tooth extraction sockets of streptozotocin-induced diabetic rats following irradiation. Mature Sprague-Dawley rats were divided into three groups: control, diabetic, and diabetic-irradiated groups. Diabetes mellitus was induced by injecting streptozotocin. Control rats were injected with a citrate buffer only. After 5 days, the right maxillary first molar was extracted under general anesthesia from each of the rats. After the extraction, rats in the diabetic-irradiated group were irradiated with a single absorbed dose of 10 Gy to the head and neck region. The rats were killed at 1, 3, 7, 14, 21, and 28 days after treatment. Tissue sections were stained with hematoxylin-eosin and Masson's trichrome. In the diabetic and diabetic-irradiated groups, the early healing process of the socket extraction was similar to the control group, but bone formation was delayed at 7 days after the treatment. In the diabetic-irradiated group, alveolar bone surrounding the extraction socket showed sighs of necrosis at 3 days after treatment, and hemorrhage was observed in connective tissue within the extraction socket at 14 days after treatment. The experiment revealed that the healing process of the extraction socket was severely delayed and retarded by irradiation in the diabetic state.

Effect of irradiation on the healing of extraction sockets in diabetic rats

International Nuclear Information System (INIS)

Kim, Il Joong; Hwang, Eui Hwan; Lee, Sang Rae

2003-01-01

To observe the histologic pattern of healing in molar tooth extraction sockets of streptozotocin-induced diabetic rats following irradiation. Mature Sprague-Dawley rats were divided into three groups: control, diabetic, and diabetic-irradiated groups. Diabetes mellitus was induced by injecting streptozotocin. Control rats were injected with a citrate buffer only. After 5 days, the right maxillary first molar was extracted under general anesthesia from each of the rats. After the extraction, rats in the diabetic-irradiated group were irradiated with a single absorbed dose of 10 Gy to the head and neck region. The rats were killed at 1, 3, 7, 14, 21, and 28 days after treatment. Tissue sections were stained with hematoxylin-eosin and Masson's trichrome. In the diabetic and diabetic-irradiated groups, the early healing process of the socket extraction was similar to the control group, but bone formation was delayed at 7 days after the treatment. In the diabetic-irradiated group, alveolar bone surrounding the extraction socket showed sighs of necrosis at 3 days after treatment, and hemorrhage was observed in connective tissue within the extraction socket at 14 days after treatment. The experiment revealed that the healing process of the extraction socket was severely delayed and retarded by irradiation in the diabetic state.

Cranial irradiation of young rats impairs later learning and growth

International Nuclear Information System (INIS)

Overmier, J.B.; Carroll, M.E.; Patten, R.; Krivit, W.; Kim, T.H.

1979-01-01

Young rats (26 days) were exposed to ionizing radiation of the head of 0, 1200, 2400 or 3000 rads total in 200 rads/day doses. The subsequent growth of irradiated rats was permanently impaired: such impairment was positively related to amount of irradiation. Beginning in adolescence, rats were trained on a horizontal/vertical visual discrimination in a runway task and although all four groups mastered the discrimination, they differed in their patterns of acquisition. These results indicated long term effects and are associated with a cranial irradiation regimen similar to that given to children suffering acute lymphocytic leukemia (ALL). (author)

Structural changes induced by electron irradiation

International Nuclear Information System (INIS)

Koike, J.; Pedraza, D.F.

1993-01-01

Highly oriented pyrolytic graphite was irradiated at room temperature with 300 kV electrons. Transmission electron microscopy and electron energy loss spectroscopy were employed to study the structural changes produced by irradiation. The occurrence of a continuous ring intensity in the selected area diffraction (SAD) pattern obtained on a specimen irradiated with the electron beam parallel to the c-crystallographic axis indicated that microstructural changes had occurred. However, from the SAD pattern obtained for the specimens tilted relative to the irradiation direction, it was found that up to a fluence of 1.1x10 27 e/m 2 graphite remained crystalline. An SAD pattern of a specimen irradiated with the electron beam perpendicular to the c-axis confirmed the persistence of crystalline order. High resolution electron microscopy showed that ordering along the c-axis direction remained. A density reduction of 8.9% due to irradiation was determined from the plasmon frequency shift. A qualitative model is proposed to explain these observations. A new determination of the threshold displacement energy, Ed, of carbon atoms in graphite was done by examining the appearance of a continuous ring in the SAD pattern at various electron energies. A value of 30 eV was obtained whether the incident electron beam was parallel or perpendicular to the c-axis, demonstrating that Ed is independent of the displacement direction

UV irradiation to mouse skin decreases hippocampal neurogenesis and synaptic protein expression via HPA axis activation.

Science.gov (United States)

Han, Mira; Ban, Jae-Jun; Bae, Jung-Soo; Shin, Chang-Yup; Lee, Dong Hun; Chung, Jin Ho

2017-11-14

The skin senses external environment, including ultraviolet light (UV). Hippocampus is a brain region that is responsible for memory and emotion. However, changes in hippocampus by UV irradiation to the skin have not been studied. In this study, after 2 weeks of UV irradiation to the mouse skin, we examined molecular changes related to cognitive functions in the hippocampus and activation of the hypothalamic-pituitary-adrenal (HPA) axis. UV exposure to the skin decreased doublecortin-positive immature neurons and synaptic proteins, including N-methyl-D-aspartate receptor 2 A and postsynaptic density protein-95, in the hippocampus. Moreover, we observed that UV irradiation to the skin down-regulated brain-derived neurotrophic factor expression and ERK signaling in the hippocampus, which are known to modulate neurogenesis and synaptic plasticity. The cutaneous and central HPA axes were activated by UV, which resulted in significant increases in serum levels of corticosterone. Subsequently, UV irradiation to the skin activated the glucocorticoid-signaling pathway in the hippocampal dentate gyrus. Interestingly, after 6 weeks of UV irradiation, mice showed depression-like behavior in the tail suspension test. Taken together, our data suggest that repeated UV exposure through the skin may negatively affect hippocampal neurogenesis and synaptic plasticity along with HPA axis activation.

Can prenatal low-dose irradiation affect behavior of adult rats?

International Nuclear Information System (INIS)

Smajda, B.; Tomasova, L.; Kokocova, N.

2011-01-01

The aim of our study was to determine whether exposure of very low dose gamma-rays during the critical phase of brain development affects some selected behavioral parameters in adult rats. Pregnant female Wistar rats were irradiated with 1 Gy gamma-rays from a cobalt source at 17 th day of pregnancy. The progeniture of irradiated as well as non-irradiated females have undergone behavioral tests at the age of 3 months. Irradiated animals exhibited lower locomotor and exploratory activity in the open field test. (authors)

Serum glucose and liver glycogen in gamma irradiated rats

International Nuclear Information System (INIS)

Ahlersova, E.; Ahlers, I.; Molcanova, A.

1988-01-01

Overnight fasted male rats of Wistar strain were irradiated with single whole-body doses of 4.78-7.17-9.57 and 14.35 Gy of gamma rays. After decapitation at intervals 1-28 d (4.78 and 7.17 Gy), 1-7 d (9.57 Gy) and 1-3 d (14.35 Gy) glucose concentration in serum and glycogen concentration in liver of irradiated and non-irradiated animals were determined. The higher was radiation dose the more expressive extent and depth of changes (hyperglycemia, accumulation of glycogen) occured. Blood glucose and liver glycogen may serve as a reliable and dose-dependent biological indicators of metabolic changes in irradiated rats. (author)

Passive transfer of resistance and the site of immune-dependent elimination of the challenge infection in rats vaccinated with highly irradiated cercariae of Schistosoma mansoni

International Nuclear Information System (INIS)

Ford, M.J.; Bickle, Q.D.; Taylor, M.G.; Andrews, B.J.

1984-01-01

The immune-dependent elimination of a challenge infection in rats vaccinated with highly-irradiated cercariae of Schistosoma mansoni was analysed by passive transfer of serum, recovery of the challenge from the lungs and livers and by transferring lung-stage schistosomula. Recipients of serum from rats immunized with either unirradiated, 20 or 40 krad.-irradiated cercariae, were equally resistant if the serum was injected on the day of infection or 5-7 days after infection. Vaccinated rat serum transferred to mice and vaccinated rabbit serum transferred to rats conferred comparable protection when injected on day 0 or 5 days after infection of the recipients. This apparent susceptibility of the lung schistosomula to immune attack was confirmed by challenging 20 or 40 krad.-irradiated cercariae vaccinated rats with lung-stage schistosomula derived from mice or rats. All the detectable attrition of a cercarial challenge in vaccinated rats occurred between 7 and 10 days post-challenge, before the parasites reached the liver. Since there was no evidence of damage or attrition in the skin or lungs before day 7 it was concluded that immune-dependent elimination occurred rapidly following a 'window of sensitivity' coinciding with the migration of the parasites from the lungs to the liver. (author)

1H-MR spectroscopy of the rat hippocampus after whole brain irradiation: an in vivo study

International Nuclear Information System (INIS)

Ding Weijun; Yang Haihua; Wang Xufeng; Hu Wei; Lei Hao; Li Chunxia; Fang Fang; Fang Zhouxi

2008-01-01

Objective: To study the relationships between dynamic changes of the hippocampus metabolites, cognitive impairment and ultrastructural changes of hippocampus in rats during the initial 4 weeks after 6 MV X-ray whole-brain irradiation. Methods: 65 rats were randomly divided into foul groups as sham control (n=5), 10 Gy, 20 Gy and 30 Gy groups (n=20). The learning and memory ability was measured with the Y maze test 4, 8 weeks, 2, 6 months after irradiation. 1 H-MRS was performed after 2 or 4 weeks' brain irradiation. The ultrastructural changes of the hippocampus were observed by electronic microscope. Results: The learning and memorizing ability of irradiation groups was significantly different from that of control group. Compared with control group, the NAA/Ct and Cho/Cr ratio in the left hippocampus in 10 Gy, 20 Gy and 30 Gy groups at 2 weeks and 4 weeks decreased significantly. Neuronal mitochondria edema, endothelial cells swelling and lamina dissociation in myelin sheath were demonstrated in various degrees by electromicroscope at 4 weeks following whole brain irradiation. Conclusions: 1 H-MRS can be used to non-invasively monitor the metabolic changes, both quantitatively and dynamically, of the irradiated rat brain, 1 H-MRS is superior to MRI in detecting early abnormality of the brain. The NAA/Cr and Cho/Cr ratio in irradiated hippocampus could reflect the severity of the brain injury to some extent. (authors)

Effects of electroacupuncture on leukocytes and plasma protein in the X-irradiated rats

International Nuclear Information System (INIS)

Hau, D.M.

1984-01-01

The effects of electroacupuncture on leukocytes and plasma protein on the X ray-irradiated rats were investigated in the present study. The results showed that X-irradiation had an evident inhibitory effect on the counts of total leukocytes, lymphocytes and neutrocytes, and the concentration of the total plasma protein, plasma albumin, globulin and alpha- and beta-globulin in X-irradiated rats. The electroacupuncture was able to help the X-irradiated rats to recover the counts of the total leukocyte, lymphocyte and neutrocyte. The electroacupuncture had a helpful tendency to recover the concentration of the total plasma protein, albumin, globulin, and alpha- and beta-globulin in the irradiated rats

Effects of electroacupuncture on leukocytes and plasma protein in the X-irradiated rats

Energy Technology Data Exchange (ETDEWEB)

Hau, D.M.

The effects of electroacupuncture on leukocytes and plasma protein on the X ray-irradiated rats were investigated in the present study. The results showed that X-irradiation had an evident inhibitory effect on the counts of total leukocytes, lymphocytes and neutrocytes, and the concentration of the total plasma protein, plasma albumin, globulin and alpha- and beta-globulin in X-irradiated rats. The electroacupuncture was able to help the X-irradiated rats to recover the counts of the total leukocyte, lymphocyte and neutrocyte. The electroacupuncture had a helpful tendency to recover the concentration of the total plasma protein, albumin, globulin, and alpha- and beta-globulin in the irradiated rats.

Application of electron beam irradiation. 4. Treatment of pollutants by electron beam irradiation

International Nuclear Information System (INIS)

Tokunaga, Okihiro; Arai, Hidehiko

1994-01-01

Electron beam irradiation is capable of dissolving and removing pollutants, such as sulfur oxides, nitrogen oxides, and organic compounds, by easy production of OH radicals in flue gas and water. This paper deals with current status in the search for techniques for treating flue gas and waste water, using electron beam irradiation. Pilot tests have been conducted during the period 1991-1994 for the treatment of flue gas caused by coal and garbage burning and road tunnels. Firstly, techniques for cleaning flue gas with electron beams are outlined, with special reference to their characteristics and process of research development. Secondly, the application of electron beam irradiation in the treatment of waste water is described in terms of the following: (1) disinfection of sewage, (2) cleaning of water polluted with toxic organic compounds, (3) treatment for eliminating sewage sludge, (4) promotion of sewage sludge sedimentation, (5) disinfection and composting of sewage sludge, and (6) regeneration of activated carbon used for the treatment of waste water. (N.K.)

Irradiation effects on the adrenal gland of rats undergoing inanition stress

International Nuclear Information System (INIS)

Hasan, S.S.; Chaturvedi, P.K.

1985-01-01

The effect of total body x-irradiation was studied on rats under inanition stress. In response to irradiation an increase in the activity of cortex and medulla was noted in inanition stress administered rats rather than in the normally fed animals. Similarly, rising levels of urinary catecholamines and 5-hydroxytryptamine were observed in the starved animals after irradiation. (author)

Influence of head X-irradiation on neuroendocrine functions in thymectomized male rats

International Nuclear Information System (INIS)

Gong Shouliang

1991-01-01

The present study showed that the functions of the hypothalamic-pituitary-gonadal and hypothalamic-adrenocortical systems changed in adult male rats thymectomized within 48 h after their birth. Two days later, head irradiation with 10 Gy x-rays was performed in the thymectomized male rats, serum LH and FSH, serum and urine testosterone and corticosterone, pituitary and testicular cAMP and hypothalamic β-EP and L-Enk contents were all reduced in different degrees, except the hypothalamic M-Enk content was increased, indicating that the changes were not in the same direction as those in intact male rats after head irradiation. These results suggest that the changes in head irradiated thymectomized male rats may differ from the changes seen in head irradiated intact male rats because of the influence of thymectomy on the neuroendocrine functions

Effect of irradiation on the temporomandibular joint in streptozotocin-induced diabetic rat

Energy Technology Data Exchange (ETDEWEB)

Ahn, Ki Dong; Hwang, Eui Hwan; Lee, Sang Rae [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

2004-06-15

To investigate the histopathological changes in the temporomandibular joint in streptozotocin-induced diabetic rat following irradiation. Sprague-Dawley rats weighing about 250 gm were divided into three groups: control, diabetic, and diabetic-irradiated groups. Diabetes mellitus was induced in the rats by injecting streptozotocin. Rats in the control group were injected with citrate buffer only. After 5 days, the head and neck region of the rats in diabetic-irradiated group were irradiated with single absorbed dose of 10 Gy. The rats were killed at 1, 3, 7, 14, 21, and 28 days after irradiation. The specimen including the temporomandibular joint were sectioned and observed using a histopathological method. In the diabetic group, severe bone resorption in the mandibular condyle was observed throughout the period of experiment. Necrosis of bone marrow and trabeculae was observed at 28 days after diabetic state. Atrophy and fibrosis in the retrodiscal tissue was gradually progressed during the time of the experiment. In the diabetic-irradiated group, severe bone resorption in the mandibular condyle was observed during the early experimental phases, but regeneration of bone marrow was initiated at 14 days after diabetic state and irradiation. Also, calcification of abnormal trabeculae was observed at 28 days after diabetic state and irradiation. The retrodiscal tissue was degenerated in the early experimental phases, but it had been gradually regenerated during the experimental time. This experiment suggests that bone resorption and degeneration in the mandibular condyle are caused by the induction of diabetes, and abnormal bone formation is induced after irradiation in diabetic state.

Effect of irradiation on the temporomandibular joint in streptozotocin-induced diabetic rat

International Nuclear Information System (INIS)

Ahn, Ki Dong; Hwang, Eui Hwan; Lee, Sang Rae

2004-01-01

To investigate the histopathological changes in the temporomandibular joint in streptozotocin-induced diabetic rat following irradiation. Sprague-Dawley rats weighing about 250 gm were divided into three groups: control, diabetic, and diabetic-irradiated groups. Diabetes mellitus was induced in the rats by injecting streptozotocin. Rats in the control group were injected with citrate buffer only. After 5 days, the head and neck region of the rats in diabetic-irradiated group were irradiated with single absorbed dose of 10 Gy. The rats were killed at 1, 3, 7, 14, 21, and 28 days after irradiation. The specimen including the temporomandibular joint were sectioned and observed using a histopathological method. In the diabetic group, severe bone resorption in the mandibular condyle was observed throughout the period of experiment. Necrosis of bone marrow and trabeculae was observed at 28 days after diabetic state. Atrophy and fibrosis in the retrodiscal tissue was gradually progressed during the time of the experiment. In the diabetic-irradiated group, severe bone resorption in the mandibular condyle was observed during the early experimental phases, but regeneration of bone marrow was initiated at 14 days after diabetic state and irradiation. Also, calcification of abnormal trabeculae was observed at 28 days after diabetic state and irradiation. The retrodiscal tissue was degenerated in the early experimental phases, but it had been gradually regenerated during the experimental time. This experiment suggests that bone resorption and degeneration in the mandibular condyle are caused by the induction of diabetes, and abnormal bone formation is induced after irradiation in diabetic state.

Garlic protects the glutathione redox cycle in irradiated rats

International Nuclear Information System (INIS)

Abu-Ghadeer, A.R.M.; Osman, S.A.A.; Abbady, M.M.

1999-01-01

The aim of the present study is to evaluate the possible radioprotective role of garlic oil on the glutathione redox cycle (GSH, GSH-Px, GR and G6-PD) in blood and tissues (liver, spleen and intestine) of irradiated rats. Garlic oil was orally administered to rats (100 mg/Kg- b.w.) for 7 days before exposure to a fractionated of whole body gamma irradiation up to 9 Gy (3 Gy X 3 at 2 days intervals) and during the whole period of irradiation. The data showed that radiation exposure caused significant inhibition of the biochemical parameters in blood and tissue of irradiated rats all over the investigation periods (3,7 and 15 days). Garlic oil ameliorated the decrease in the tested parameters with noticeable effect on the 15 Th. day after radiation exposure. It is concluded that garlic oil could control the radiation induced changes in the glutathione redox cycle and provided some radioprotective effect

Immunity to Schistosoma mansoni in congenitally athymic, irradiated and mast cell-depleted rats

International Nuclear Information System (INIS)

Ford, M.J.; Bickle, Q.D.; Taylor, M.G.

1987-01-01

Immunity to Schistosoma mansoni was investigated in congenitally athymic (Nu/Nu) rats, irradiated rats and in mast cell-depleted rats. Nu/Nu rats failed to develop significant resistance following vaccination with irradiated cercariae, although Nu/Nu recipients of serum from vaccinated Fischer rats (VRS) manifested resistance comparable to heterozygous controls, suggesting that T-cells were required in the induction of resistance but were not involved in the efferent arm of antibody-dependent elimination. Radiosensitive cells (including eosinophils, basophils, neutrophils, lymphocytes and mast cells) were apparently not essential for the antibody-dependent elimination of lung or post-lung stages since irradiated (700-750 rad.) recipients of VRS manifested comparable degrees of resistance to unirradiated controls in spite of a greater than 85% reduction in total blood leucocyte counts after irradiation. Depletion of 99% of tissue mast cells by treatment of rats with Compound 48/80 had no significant effect on the attrition of a challenge infection in rats rendered immune by vaccination with irradiated cercariae or by transfer of VRS. However, there was a significant increase in worm recovery in unimmunized and mast cell-depleted or irradiated rats, indicating that mast cells and perhaps other radio-isotope sensitive cells may be involved in innate resistance. (author)

Immunity to Schistosoma mansoni in congenitally athymic, irradiated and mast cell-depleted rats

Energy Technology Data Exchange (ETDEWEB)

Ford, M.J.; Bickle, Q.D.; Taylor, M.G.

1987-04-01

Immunity to Schistosoma mansoni was investigated in congenitally athymic (Nu/Nu) rats, irradiated rats and in mast cell-depleted rats. Nu/Nu rats failed to develop significant resistance following vaccination with irradiated cercariae, although Nu/Nu recipients of serum from vaccinated Fischer rats (VRS) manifested resistance comparable to heterozygous controls, suggesting that T-cells were required in the induction of resistance but were not involved in the efferent arm of antibody-dependent elimination. Radiosensitive cells (including eosinophils, basophils, neutrophils, lymphocytes and mast cells) were apparently not essential for the antibody-dependent elimination of lung or post-lung stages since irradiated (700-750 rad.) recipients of VRS manifested comparable degrees of resistance to unirradiated controls in spite of a greater than 85% reduction in total blood leucocyte counts after irradiation. Depletion of 99% of tissue mast cells by treatment of rats with Compound 48/80 had no significant effect on the attrition of a challenge infection in rats rendered immune by vaccination with irradiated cercariae or by transfer of VRS. However, there was a significant increase in worm recovery in unimmunized and mast cell-depleted or irradiated rats, indicating that mast cells and perhaps other radio-isotope sensitive cells may be involved in innate resistance.

Study of the biochemical indicators of chronic irradiation in rats.

Science.gov (United States)

Szabo, L D; Benko, A B; Gyenge, L; Predmerszky, T

1976-01-01

Daily urinary excretion of pseudouridine, creatinine and creatine of chronically irradiated Wistar rats was estimated. The irradiation conditions were: 60Co gamma source, dose-rate 10 rad/day, total dose 200, 400 and 600 rad. Control groups were kept under similar conditions. Urine samples were taken three times after the end of the irradiation period. It was found that: (1) pseudouridine excretion seems more suitable for indicating radiation injury than the creatine/creatinine ratio in chronic irradiation in rats; (ii) there are significant changes in dose dependence of pseudouridine excretion in the post-irradiation period; (iii) a new method for pseudouridine estimation gives closely similar data to those of earlier investigations.

The absorption of p-toluenediamine by the skin of rats and dogs

International Nuclear Information System (INIS)

Hruby, R.

1977-01-01

The cutaneous absorption of p-[Me- 14 C]toluenediamine, applied in formulations similar to those normally used for hair dyeing, was investigated in rats and dogs. When rat skin was exposed for 30 min to two different formulations, about 0.2% of the administered amount of p-toluenediamine was absorbed in each case. Excretion of the absorbed substance took place predominantly in the urine. At the end of the 24-hr experiment, a residue of 5.2 to 9.3% of the dose was found in the treated area of rat skin. Experiments with oral and subcutaneous application to the rat also demonstrated rapid elimination of the toluenediamine. Dog skin was exposed to one formulation containing p-toluenediamine for 3 hr. It is estimated that about 0.13% of the administered p-toluenediamine was absorbed. (author)

Electron trapping during irradiation in reoxidized nitrided oxide

International Nuclear Information System (INIS)

Mallik, A.; Vasi, J.; Chandorkar, A.N.

1993-01-01

Isochronal detrapping experiments have been performed following irradiation under different gate biases in reoxidized nitrided oxide (RNO) MOS capacitors. These show electron trapping by the nitridation-induced electron traps at low oxide fields during irradiation. A difference in the detrapping behavior of trapped holes and electrons is observed, with trapped holes being detrapped at relatively lower temperatures compared to trapped electrons. Electron trapping shows a strong dependence on tile magnitude of the applied gate bias during irradiation but is independent of its polarity. Conventional oxide devices, as expected, do not show any electron trapping during irradiation by the native electron traps. Finally, a comparison of the isochronal detrapping behavior following irradiation and following avalanche injection of electrons has been made to estimate the extent of electron trapping. The results show that electron trapping by the nitridation-induced electron traps does not play the dominant role in improving radiation performance of RNO, though its contribution cannot be completely neglected for low oxide field irradiations

Induction of resveratrol biosynthesis in skins of three grape cultivars by ultraviolet irradiation

International Nuclear Information System (INIS)

Takayanagi, Tsutomu; Okuda, Tohru; Mine, Yohei; Yokotsuka, Koki

2004-01-01

Resveratrol production and expression of the genes related to resveratrol biosynthesis were investigated in the skins of three Vitis vinifera cultivars Chardonnay, Koshu and an American hybrid grape, Muscat Bailey A (Bailey x Muscat Hamburg). Resveratrol concentration in the skins of all the grapes increased significantly when exposed to ultraviolet (UV-C, 254 nm) irradiation. The UV-induced resveratrol concentration in the grape skins was lower after veraison (onset of ripening) than before it. The maximum concentration of the UV-induced resveratrol in 'Muscat Bailey A' was higher than those in the other two cultivars. The relative mRNA expression levels of stilebene synthase (STS), phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS) genes in grape skins 8 hr after UV irradiation were determined by quantitative reverse transcription-polymerase chain reaction (RT-PCR). The results revealed that STS- and PAL-mRNA expressions were significantly increased by UV irradiation. STS-mRNA expressions in 'Muscat Bailey A' were higher than those in 'Chardonnay' throughout berry development. The UV-induced CHS-mRNA expression in the grape skins decreased before veraison and subsequently increased. (author)

Prolongation of rat islet allograft survival by direct ultraviolet irradiation of the graft

International Nuclear Information System (INIS)

Lau, H.; Reemtsma, K.; Hardy, M.A.

1984-01-01

Ultraviolet irradiation of rat dendritic cells completely abrogated their allostimulatory capacity in a mixed lymphocyte reaction. Rat islets of Langerhans similarly irradiated remained hormonally functional when transplanted into syngeneic diabetic rats. Allogeneic transplantation across a major histocompatibility barrier of islets initially treated in vitro with ultraviolet irradiation resulted in prolonged allograft survival without the use of any immunosuppressive agents

Skin response to cobalt 60 irradiation and the consequences for matching the color of facial prostheses

International Nuclear Information System (INIS)

van Oort, R.P.; Vermey, J.; Ten Bosch, J.J.

1984-01-01

A radiotherapy treatment ( 60 Co) of cancer in the head and neck region causes side effects in the skin that postpone the facial prosthetic treatment. The increasing and fading erythema and pigmentation of the skin was investigated with the use of a subtractive colorimeter. This method was verified with photographs scored according to the Oxford scoring system. Fourteen patients were investigated during a period of 24 weeks. The mean colorimetric skin response showed a peak 6 weeks after the onset of irradiation. Six to 7 weeks later, there was no significant difference between the skin color before and after irradiation. At this time the dry desquamation of the skin is healed. From this viewpoint, the color matching procedure for a facial prosthesis may start not earlier than 15 weeks from the onset of irradiation. If a nonirradiated control field in the facial region is present, a color match for the facial prosthesis can be started just after the irradiation period

Unscheduled DNA synthesis after β-irradiation of mouse skin in situ

International Nuclear Information System (INIS)

Ootsuyama, Akira; Tanooka, Hiroshi

1986-01-01

The skin of ICR mouse was irradiated with β-rays from 90 Sr- 90 Y with surface doses up to 30 krad. Unscheduled DNA synthesis (UDS) was measured by autoradiography after labeling the skin with radioactive thymidine using the forceps-clamping method. The level of UDS in epithelial cells of the skin was detected as an increasing function of radiation dose. Fibroblastic cells, compared with epithelial cells and hair follicle cells at the same depth of the skin, showed a lower level of UDS, indicating a lower DNA repair activity in fibroblasts. Cancer risk of the skin was discussed. (Auth.)

Role of Leaves of Salvia Officinalis L. Extract in the Restitution of Lipid Composition and Minimizing the Free Radicals Concentration in Irradiated Rats

International Nuclear Information System (INIS)

Fahim, Th.M.; Mansour, S.Z.

2011-01-01

The present study sought to determine the antioxidant activity and the protective ability of water-extractable phytochemicals from Salvia officinalis leaves (strongly aromatic leaves) on lipid fractions and peroxidation degree induced by irradiated rats serum, liver and brain homogenates. Total free radicals generated in blood were examined by electron spin resonance (ESR). Four equal groups were chosen for the study: control, Salvia officinalis treated (1ml/kg body wt), Irradiated (fractionated dose of gamma-irradiation (6Gy) delivered as 1.5 Gy two times a week for 2 weeks) and Salvia officinalis plus irradiation group (rats received Salvia officinalis for 14 days before irradiation and daily within the period of irradiation (2 weeks), and seven days post the last radiation dose. Irradiation of rats caused biochemical alterations represented by markedly elevated levels of lipid fractions in serum, lipid peroxidation level in liver and brain tissues. Also, radiation of rats showed a significant decline in most unsaturated fatty acids concentration. The study pointed out to the promising positive role of Salvia officinalis as a nontoxic natural product to reduce oxidative stress and protect vital physiological processes post radiation exposure.

UV irradiation-induced methionine oxidation in human skin keratins: Mass spectrometry-based non-invasive proteomic analysis.

Science.gov (United States)

Lee, Seon Hwa; Matsushima, Keita; Miyamoto, Kohei; Oe, Tomoyuki

2016-02-05

Ultraviolet (UV) radiation is the major environmental factor that causes oxidative skin damage. Keratins are the main constituents of human skin and have been identified as oxidative target proteins. We have recently developed a mass spectrometry (MS)-based non-invasive proteomic methodology to screen oxidative modifications in human skin keratins. Using this methodology, UV effects on methionine (Met) oxidation in human skin keratins were investigated. The initial screening revealed that Met(259), Met(262), and Met(296) in K1 keratin were the most susceptible oxidation sites upon UVA (or UVB) irradiation of human tape-stripped skin. Subsequent liquid chromatography/electrospray ionization-MS and tandem MS analyses confirmed amino acid sequences and oxidation sites of tryptic peptides D(290)VDGAYMTK(298) (P1) and N(258)MQDMVEDYR(267) (P2). The relative oxidation levels of P1 and P2 increased in a time-dependent manner upon UVA irradiation. Butylated hydroxytoluene was the most effective antioxidant for artifactual oxidation of Met residues. The relative oxidation levels of P1 and P2 after UVA irradiation for 48 h corresponded to treatment with 100mM hydrogen peroxide for 15 min. In addition, Met(259) was oxidized by only UVA irradiation. The Met sites identified in conjunction with the current proteomic methodology can be used to evaluate skin damage under various conditions of oxidative stress. We demonstrated that the relative Met oxidation levels in keratins directly reflected UV-induced damages to human tape-stripped skin. Human skin proteins isolated by tape stripping were analyzed by MS-based non-invasive proteomic methodology. Met(259), Met(262), and Met(296) in K1 keratin were the most susceptible oxidation sites upon UV irradiation. Met(259) was oxidized by only UVA irradiation. Quantitative LC/ESI-SRM/MS analyses confirmed a time-dependent increase in the relative oxidation of target peptides (P1 and P2) containing these Met residues, upon UVA irradiation

Skin carcinogenesis following uniform and non-uniform β irradiation

International Nuclear Information System (INIS)

Charles, M.W.; Williams, J.P.; Coggle, J.E.

1989-01-01

Where workers or the general public may be exposed to ionising radiation, the irradiation is rarely uniform. The risk figures and dose limits recommended by the International Commission on Radiological Protection (ICRP) are based largely on clinical and epidemiological studies of reasonably uniform irradiated organs. The paucity of clinical or experimental data for highly non-uniform exposures has prevented the ICRP from providing adequate recommendations. This weakness has led on a number of occasions to the postulate that highly non-uniform exposures of organs could be 100,000 times more carcinogenic than ICRP risk figures would predict. This so-called ''hot-particle hypothesis'' found little support among reputable radiobiologists, but could not be clearly and definitively refuted on the basis of experiment. An experiment, based on skin tumour induction in mouse skin, is described which was developed to test the hypothesis. The skin of 1200 SAS/4 male mice has been exposed to a range of uniform and non-uniform sources of the β emitter 170 Tm (E max ∼ 1 MeV). Non-uniform exposures were produced using arrays of 32 or 8 2-mm diameter sources distributed over the same 8-cm 2 area as a uniform control source. Average skin doses varied from 2-100 Gy. The results for the non-uniform sources show a 30% reduction in tumour incidence by the 32-point array at the lower mean doses compared with the response from uniform sources. The eight-point array showed an order-of-magnitude reduction in tumour incidence compared to uniform irradiation at low doses. These results, in direct contradiction to the ''hot particle hypothesis'', indicate that non-uniform exposures produce significantly fewer tumours than uniform exposures. (author)

Comparison of dosimetric mapping of radiation induced skin ulcer animal model in Nud mice and Wistar rat

Energy Technology Data Exchange (ETDEWEB)

Alves, Nelson M.; Mosca, Rodrigo C.; Ferreira, Danilo C.; Somessari, Elizabeth S.R.; Silveira, Carlos Gaia da; Dornelles, Leonardo D.P.; Bueno, Carmem C.; Mathor, Monica B., E-mail: nelsonnininho@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

Skin ulcer (SU) is the damage caused to the skin by ionizing radiation, becoming evident at the end or after the conclusion of radiotherapeutic treatments. Technological advances have enabled dose increases in radiotherapy protocols, augmenting SU cases. In order to investigate potential therapies for the SU, an animal model (AM) was devised for Wistar rats, based upon the AM of the Nud mice. The AM dose rate (DR) was measured with silicium diode in the gamma irradiator and lead blocks. Three animals were positioned into immobilizers with their dorsal region skin pinched and held up by a suture point fixed in the immobilizer and exposed to 85 Gy. The DR variation in the immobilizer tangential point with the source median plane was non-significant, thus establishing an average DR. Such shielding reduced the DR in the rat in more than 93%. The difference in the immobilizer's dimensions impaired the comparison between the DRs; nevertheless, the DR comparison in the immobilizer tangential point with the source median plane became the reference point for AM comparison. The appearance of SU symptoms and their maximum extensions were similar, notwithstanding the difference regarding their healing periods. The specified dose induced the SU emerging. Mass variation exerted no influence onto the healing, despite having age affected it. The animals, throughout and after the experiment, showed normal health with just the SU symptoms. This work granted us the AM for the Wistar rats, which shall reinforce the investigation of new therapies for SU treatment. (author)

Comparison of dosimetric mapping of radiation induced skin ulcer animal model in Nud mice and Wistar rat

International Nuclear Information System (INIS)

Alves, Nelson M.; Mosca, Rodrigo C.; Ferreira, Danilo C.; Somessari, Elizabeth S.R.; Silveira, Carlos Gaia da; Dornelles, Leonardo D.P.; Bueno, Carmem C.; Mathor, Monica B.

2013-01-01

Skin ulcer (SU) is the damage caused to the skin by ionizing radiation, becoming evident at the end or after the conclusion of radiotherapeutic treatments. Technological advances have enabled dose increases in radiotherapy protocols, augmenting SU cases. In order to investigate potential therapies for the SU, an animal model (AM) was devised for Wistar rats, based upon the AM of the Nud mice. The AM dose rate (DR) was measured with silicium diode in the gamma irradiator and lead blocks. Three animals were positioned into immobilizers with their dorsal region skin pinched and held up by a suture point fixed in the immobilizer and exposed to 85 Gy. The DR variation in the immobilizer tangential point with the source median plane was non-significant, thus establishing an average DR. Such shielding reduced the DR in the rat in more than 93%. The difference in the immobilizer's dimensions impaired the comparison between the DRs; nevertheless, the DR comparison in the immobilizer tangential point with the source median plane became the reference point for AM comparison. The appearance of SU symptoms and their maximum extensions were similar, notwithstanding the difference regarding their healing periods. The specified dose induced the SU emerging. Mass variation exerted no influence onto the healing, despite having age affected it. The animals, throughout and after the experiment, showed normal health with just the SU symptoms. This work granted us the AM for the Wistar rats, which shall reinforce the investigation of new therapies for SU treatment. (author)

Late occurring lesions in the skin of rats after repeated doses of X-rays

International Nuclear Information System (INIS)

Hopewell, J.W.

1985-01-01

Late radiation damage, characterized by atrophy and necrosis in the skin and subcutaneous tissues, has been demonstrated in both the tail and feet of rats. The incidence of necrosis increased with total dose. These total doses, in the range 72-144 Gy, were given as 4-8 treatment of 18 Gy, each dose separated from the next by an interval of 28 days. This treatment protocol minimized acute epithelial skin reactions. The same regime applied to the skin on the back of rats resulted in a very severe acute reaction occurring after the second to fifth dose of 18 Gy. This was surprising since back skin, like tail skin, is less sensitive to large single doses of radiation than that of the foot. The late radiation reaction in the foot and tail of rats are compared and contrasted with other attempts to assess late effects in rodent skin and with late changes seen in pig skin. (author)

Skin-Inspired Electronics: An Emerging Paradigm.

Science.gov (United States)

Wang, Sihong; Oh, Jin Young; Xu, Jie; Tran, Helen; Bao, Zhenan

2018-05-15

Future electronics will take on more important roles in people's lives. They need to allow more intimate contact with human beings to enable advanced health monitoring, disease detection, medical therapies, and human-machine interfacing. However, current electronics are rigid, nondegradable and cannot self-repair, while the human body is soft, dynamic, stretchable, biodegradable, and self-healing. Therefore, it is critical to develop a new class of electronic materials that incorporate skinlike properties, including stretchability for conformable integration, minimal discomfort and suppressed invasive reactions; self-healing for long-term durability under harsh mechanical conditions; and biodegradability for reducing environmental impact and obviating the need for secondary device removal for medical implants. These demands have fueled the development of a new generation of electronic materials, primarily composed of polymers and polymer composites with both high electrical performance and skinlike properties, and consequently led to a new paradigm of electronics, termed "skin-inspired electronics". This Account covers recent important advances in skin-inspired electronics, from basic material developments to device components and proof-of-concept demonstrations for integrated bioelectronics applications. To date, stretchability has been the most prominent focus in this field. In contrast to strain-engineering approaches that extrinsically impart stretchability into inorganic electronics, intrinsically stretchable materials provide a direct route to achieve higher mechanical robustness, higher device density, and scalable fabrication. The key is the introduction of strain-dissipation mechanisms into the material design, which has been realized through molecular engineering (e.g., soft molecular segments, dynamic bonds) and physical engineering (e.g., nanoconfinement effect, geometric design). The material design concepts have led to the successful demonstrations of

Long-range correlations of electroencephalogram in rats irradiated by millimeter wave

International Nuclear Information System (INIS)

Xie Taorong; Pei Jian; Li Fen; Zhang Jie; Qi Hongxing; Chen Shude; Qiao Dengjiang

2011-01-01

A quantitative study was conducted on stress reaction in rat induced by 35 GHz millimeter wave. Long-range correlations analysis of the rat electroencephalogram(EEG) was investigated. The scaling exponents α 1 and α 2 were calculated by de-trended fluctuation analysis (DFA) method. The exponent α 1 shows that the high frequency EEG component is characterized by Brownian noise before irradiated by 35 GHz millimeter wave while it has long-range correlations during irradiation. The exponent α 2 shows that the low frequency EEG component has long-range correlations before irradiation while it is characterized by Brownian noise during irradiation. Introducing stress parameter k(k=α 2 /α 1 ), the average change rate of k was used to evaluate the intensity of stress in rat evoked by 35 GHz millimeter wave. The k increases 49.9%±13.6% during irradiation, which indicates that the high frequency EEG component becomes more ordered and the low frequency EEG component becomes more disordered, showing the acute stress in rat induced by 35 GHz millimeter wave. (authors)

Characteristic effects of heavy ion irradiation on the rat brain

International Nuclear Information System (INIS)

Sun, X.Z.; Takahashi, S.; Kubota, Y.; Yoshida, S.; Takeda, H.; Zhang, R.; Fukui, Y.

2005-01-01

Heavy ion irradiation has the feature to administer a large radiation dose in the vicinity of the endpoint in the beam range, and its irradiation system and biophysical characteristics are different from ordinary irradiation instruments like X- or gamma-rays. Using this special feature, heavy ion irradiation has been applied for cancer treatment. The safety and efficacy of heavy ion irradiator have been demonstrated to a great extent. For instance, brain tumors treated by heavy-ion beams became smaller or disappearance. However, fundamental research related to such clinical phenotypes and their underlying mechanisms are little known. In order to clarify characteristic effects of heavy ion irradiation on the brain, we developed an experimental system for irradiating a restricted region of the rat brain using heavy ion beams. The characteristics of the heavy ion beams, histological, behavioral and elemental changes were studied in the rat following heavy ion irradiation. Adult male Sprague-Dawley rats, aged 12 weeks and weighing 260-340 g (Shizuoka Laboratory Animal Center, Hamamatsu, Japan) were used. Rats were deeply anesthetized 10-15 minutes before irradiation with ketamine (40 mg/kg) and xylazine (10 mg/kg), immobilized in a specifically designed jig, and irradiated with 290 MeV/nucleon charged carbon beams in a dorsal-to ventral direction, The left cerebral hemispheres of the brain were irradiated at doses of 100 Gy charged carbon particles. The depth-dose distribution of the heavy ion beams was modified to make a spread-out bragg peak of 5 mm wide with a range modulator. The characteristics of the heavy-ion beams (field and depth of the heavy-ion beams) were examined by a measuring paraffin section of rat brain at different thickness. That extensive necrosis was observed between 2.5 mm and 7.5 mm depth from the surface of the rat head, suggesting a relatively high dose and uniform dose was delivered among designed depths and the spread-out bragg peak used here

Similarity between the effects of carbon-ion irradiation and X-irradiation on the development of rat brain

International Nuclear Information System (INIS)

Inouye, Minoru; Hayasaka, Shizu; Murata, Yoshiharu; Takahashi, Sentaro; Kubota, Yoshihisa

2000-01-01

The effects of carbon-ion irradiation and X-irradiation on the development of rat brain were compared. Twenty pregnant rats were injected with bromodeoxyuridine (BrdU) at 9 pm on day 18 pregnancy and divided into five groups. Three hours after injection (day 19.0) one group was exposed to 290 MeV/u carbon-ion radiation by a single dose of 1.5 Gy. Other groups were exposed to X-radiation by 1.5, 2.0 or 2.5 Gy, or sham-treated, respectively. Fetuses were removed from one dam in each group 8 h after exposure and examined histologically. Extensive cell death was observed in the brain mantle from the irradiated groups. The cell death after 1.5 Gy carbon-ion irradiation was remarkably more extensive than that after 1.5 Gy X-irradiation, but comparable to that after 2.0 Gy or 2.5 Gy X-irradiation. The remaining rats were allowed to give birth and the offspring were sacrificed at 6 weeks of age. All of the irradiated offspring manifested microcephaly. The size of the brain mantle exposed to 1.5 Gy carbon-ion radiation was significantly smaller than that exposed to 1.5 Gy X-radiation and larger than that exposed to 2.5 Gy X-radiation. A histological examination of the cerebral cortex revealed that cortical layers II-IV were malformed. The defect by 1.5 Gy carbon-ion irradiation was more severe than that by the same dose of X-irradiation. Although the BrdU-incorporated neurons were greatly reduced in number in all irradiated groups, these cells reached the superficial area of the cortex. These findings indicated that the effects of both carbon-ion irradiation and X-irradiation on the development of rat brain are similar in character, and the effect of 1.5 Gy carbon-ion irradiation compares to that of 2.0-2.5 Gy X-irradiation. (author)

Electron irradiation of power transistors

International Nuclear Information System (INIS)

Hower, P.L.; Fiedor, R.J.

1982-01-01

A method for reducing storage time and gain parameters in a semiconductor transistor includes the step of subjecting the transistor to electron irradiation of a dosage determined from measurements of the parameters of a test batch of transistors. Reduction of carrier lifetime by proton bombardment and gold doping is mentioned as an alternative to electron irradiation. (author)

Quantitative histological studies on aging changes in cerebral cortex of rhesus monkey and albino rat with notes on effects of prolonged low-dose ionizing irradiation in the rat

International Nuclear Information System (INIS)

Brizzee, K.R.

1973-01-01

Brains of a series of eight young adult control (150 days) and eight middle-aged control (550 days) rats were fixed by a two-stage perfusion procedure employing Heidenhain's 'susa' solution. An equal number of rats were exposed to γ-irradiation at 6.5 R/day beginning on the 50th postnatal day and were sacrificed in the same manner and at the same age levels as the previous group. Paraffin sections were cut at 20 and 6 μ from cerebral cortical area 3 in the rat brains. Sections used for cell counts were stained with Harris' hematoxylin and eosin or iron hematoxylin, gallocyanin, acid fuchsin and ponceau de xylidene. Counts of neurons and glia were carried out at 20 equally spaced submolecular depth levels, and cell frequency profiles were plotted for each of the two cell types. The mean neuron and glial packing density for the total depth of the submolecular cortex of area 3 was not significantly different in young adult and middle-aged controls or in young adult irradiated (total dose 650 R) and control animals. However, statistical evaluation of data for relative depth levels 7 through 20 indicated that the packing density in this zone was significantly less (P<0.02) in middle-aged controls than in young adult animals. In middle-aged irradiated rats (total dose about 3250 R) neuron and glial packing densities for total depth of submolecular cortex were not significantly different than in control animals at the same age level. However, the values obtained for neuron packing density at relative depth levels 1 through 8 were significantly lower in middle-aged irradiated than in middle-aged control rats. The neuron packing density in middle-aged irradiated rats was significantly lower than in the young adult irradiated males. In electron micrographs, an increase in the amount of glycogen granules in astrocyte cell processes in cerebral cortex of irradiated middle-aged rats was noted, but there was no evidence of any other ultrastructural alterations

Effects of whole-body and partial-body x irradiation upon epidermal mitotic activity during wound healing in mouse skin

International Nuclear Information System (INIS)

Kobayashi, K.

1977-01-01

Mitotic activity of normal (unwounded) and wounded skin was measured in the control (nonirradiated) and whole-body or partial-body x-irradiated mouse. Higher mitotic activity in the anterior than in the posterior region of the body was found in both the normal and the wounded skin of the control mouse. Whole-body irradiation (500 R) depressed completely the mitotic activity of normal skin 2 to 4 days after irradiation. In spite of this depression in mitotic activity, a surgical incision made 1 to 3 days after irradiation could induce a burst of proliferation after an inhibition of an initial mitosis increase. When the animals were partially irradiated with 500 R 3 days before wounding, it was shown that mitosis at 24 hr after wounding was inhibited markedly by the local effect of irradiation and that mitosis also could be inhibited diversely by the abscopal effect of irradiation. Because of a close similarity of sequential mitotic patterns between whole-body-irradiated and flapped-skin-only-irradiated groups (direct irradiation), the effect of irradiation upon mitosis was considered to be primarily local. Some discussions were made concerning the possible reasons which made a difference in mitotic patterns between the head-only-irradiated group, the irradiated group including the head and other parts of the body except for the skin flap

Oral warfarin intake affects skin inflammatory cytokine responses in rats.

Science.gov (United States)

Aleksandrov, Aleksandra Popov; Mirkov, Ivana; Zolotarevski, Lidija; Ninkov, Marina; Mileusnic, Dina; Kataranovski, Dragan; Kataranovski, Milena

2017-09-01

Warfarin is an anticoagulant used in prevention/prophylaxis of thromboembolism. Besides the effects on coagulation, non-hemorrhagic reactions have also been documented. Although cutaneous reactions were reported in some patients, the impact on skin immunity was not explored. In the present paper, the effect of 30-day oral warfarin intake on skin cytokine responses in rats was analyzed. Increased release of inflammatory cytokines (TNF, IL-1β and IL-10) was noted by skin explants from rats which received warfarin, but without effect on IL-6. No impact on epidermal cell cytokine secretion was seen, except a tendency of an increase of IL-6 response to stimulation with microbial product lipopolysaccharide (LPS). Topical application of contact allergen dinitrochlorobenzene (DNCB) resulted in slight (numerical solely) increase of TNF release by skin explants of warfarin-treated animals, while epidermal cells responded by increased secretion of all four cytokines examined. The data presented provide new information on the potential of oral warfarin to modulate skin innate immune activity. Copyright © 2017 Elsevier B.V. All rights reserved.

[Studies on transdermal delivery of ferulic acid through rat skin treated by microneedle arrays].

Science.gov (United States)

Yang, Bing; Du, Shou-ying; Bai, Jie; Shang, Ke-xin; Lu, Yang; Li, Peng-yue

2014-12-01

In order to investigate the characteristics of transdermal delivery of ferulic acid under the treated of microneedle arrays and the influence on permeability of rat skin capillaries, improved Franz-cells were used in the transdermal delivery experiment with the rat skin of abdominal wall and the length of microneedle arrays, different insertion forces, retention time were studied in the influence of characteristics of transdermal delivery of FA. The amount of FA was determined by HPLC system. Intravenous injection Evans blue and FA was added after microneedle arrays treated. Established inflammation model was built by daubing dimethylbenzene. The amount of Evans blue in the rat skin was read at 590 nm wavelength with a Multiskan Go microplate reader. Compared with passive diffusion group the skin pretreated with microneedle arrays had a remarkable enhancement of FA transport (P Microneedle arrays with different length had a remarkable enhancement of FA transport, but was not related to the increase of the length. The research of FA on the reduce of permeability of rat skin capillaries indicated that the skin pretreated with microneedle arrays could reduce the content of Evans blue in the skins of rat significantly compared with the untreated group. The permeation rate of ferulic acid transdermal delivery had remarkable increase under the treated of microneedle arrays and the length of microneedle arrays ,the retention time so as to the insertion force were important to the transdermal delivery of ferulic acid.

Electron irradiation of zeolites

International Nuclear Information System (INIS)

Wang, S.X.; Wang, L.M.; Ewing, R.C.

1999-01-01

Three different zeolites (analcime, natrolite, and zeolite-Y) were irradiated with 200 keV and 400 keV electrons. All zeolites amorphized under a relatively low electron fluence. The transformation from the crystalline-to-amorphous state was continuous and homogeneous. The electron fluences for amorphization of the three zeolites at room temperature were: 7.0 x 10 19 e - /cm 2 (analcime), 1.8 x 10 20 e - /cm 2 (natrolite), and 3.4 x 10 20 e - /cm 2 (zeolite-Y). The different susceptibilities to amorphization are attributed to the different channel sizes in the structures which are the pathways for the release of water molecules and Na + . Natrolite formed bubbles under electron irradiation, even before complete amorphization. Analcime formed bubbles after amorphization. Zeolite-Y did not form bubbles under irradiation. The differences in bubble formation are attributed to the different channel sizes of the three zeolites. The amorphization dose was also measured at different temperatures. An inverse temperature dependence of amorphization dose was observed for all three zeolites: electron dose for amorphization decreased with increasing temperature. This unique temperature effect is attributed to the fact that zeolites are thermally unstable. A semi-empirical model was derived to describe the temperature effect of amorphization in these zeolites

Repopulation in irradiated pig skin: late versus early effects

International Nuclear Information System (INIS)

Redpath, J.L.; Peel, D.M.; Dodd, P.; Simmonds, R.H.; Hopewell, J.W.

1985-01-01

In the first 16 weeks after irradiation, two distinct waves of reaction can be observed in pig skin, the first wave (3-9 weeks) represents the expression of damage to the epithelium while the second is indicative of primary damage to the dermis, mediated through vascular injury. Comparison of single doses with two equal doses separated by 28 days produced a D 2 -D 1 value of 14.0 Gy at the doses which produced moist desquamation in 50% of fields (ED 50 ) after strontium-90 irradiation. After X-irradiation, comparison of ED 50 doses for the later dermal reaction suggested a D 2 -D 1 value of 4.2 Gy. These values of D 2 -D 1 for epithelial and dermal reactions in pig skin were compared with earlier data from this laboratory for similar split-dose experiments with a one-day interval. Such a comparison allowed for the estimation of the component of recovery in the present 28-day interval experiments due to repopulation. This component was found to be 6.5 Gy for the early epithelial damage, but was zero for the later dermal damage. (Auth.)

Cognitive dysfunction and histological findings in adult rats one year after whole brain irradiation

International Nuclear Information System (INIS)

Akiyama, Katsuhiko; Tanaka, Ryuichi; Sato, Mitsuya; Takeda, Norio

2001-01-01

Cognitive dysfunction and histological changes in the brain were investigated following irradiation in 20 Fischer 344 rats aged 6 months treated with whole brain irradiation (WBR) (25 Gy/single dose), and compared with the same number of sham-irradiated rats as controls. Performance of the Morris water maze task and the passive avoidance task were examined one year after WBR. Finally, histological and immunohistochemical examinations using antibodies to myelin basic protein (MBP), glial fibrillary acidic protein (GFAP), and neurofilament (NF) were performed of the rat brains. The irradiated rats continued to gain weight 7 months after WBR whereas the control rats stopped gaining weight. Cognitive functions in both the water maze task and the passive avoidance task were lower in the irradiated rats than in the control rats. Brain damage consisting of demyelination only or with necrosis was found mainly in the body of the corpus callosum and the parietal white matter near the corpus callosum in the irradiated rats. Immunohistochemical examination of the brains without necrosis found MBP-positive fibers were markedly decreased in the affected areas by irradiation; NF-positive fibers were moderately decreased and irregularly dispersed in various shapes in the affected areas; and GFAP-positive fibers were increased, with gliosis in those areas. These findings are similar to those in clinically accelerated brain aging in conditions such as Alzheimer's disease, Binswanger's disease, and multiple sclerosis. (author)

Investigation of photon-magnetic therapy efficacy in prevention and treatment of experimental local radiation skin lesions. Communication 1. The peculiarities of the course of radiation dermatitis in rats at spontaneous healing and at application of photon-magnetic therapy

International Nuclear Information System (INIS)

Syimonova, L.Yi.; Byilogurova, L.V.; Gertman, V.Z.; Kurov, O.M.

2012-01-01

Local x-ray exposure of the rats at a dose of 50.0 Gy caused development of radiation dermatitis with imperfect skin healing with scars and incomplete restoration of the fleece as a consequence. Administration of photon-magnetic therapy positively influenced healing of skin radiation lesions in locally irradiated animals

Abnormal G1 arrest in the cell lines from LEC strain rats after X-irradiation

International Nuclear Information System (INIS)

Hayashi, M.; Uehara, K.; Kirisawa, R.; Endoh, D.; Arai, S.; Okui, T.

1997-01-01

The effect of X-irradiation of cell lines from LEC and WKAH strain rats on a progression o cell cycle was investigated. When WKAH rat ells were exposed to 5 Gy of X-rays and their cell cycle distribution was determined by a flow cytometer, the proportion of S-phase cells decrease and that of G2/M-phase cells in creased at 8 hr post-irradiation. At 18 and 24 hr post-irradiation, approximately 80% of the cells appeared in the G1 phase. On the contrary, the proportion of S-phase cells increased and that of G1-phase cells decreased in LEC rats during 8-24 hr post-irradiation, compared with that at 0 hr post-irradiation. Thus, radiation-induced delay in the progression from the G1 phase to S phase (G1 arrest) was observed inWKAH rat cells but not in LEC rat cells. In the case of WKAH rat cells, the intensities of the bands of p53 protein increased at 1 and 2 hr after X-irradiation at 5 Gy, compared with those of un-irradiated cells and at 0 hr post-irradiation. In contrast, the intensities of the bands were faint and did not significantly increase in LEC rat ells during 0-6 hr incubation after X-irradiation. Present results suggested that the radioresistant DNA synthesis in LEC rat cells is thought to be due to the abnormal G1 arrest following X-irradiation

Effect of Topical Probiotic on MMP-13 and Collagen III Expression in the Dermis Layer of Male Rats Irradiated with Ultraviolet-B

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Vita M. Tawaran

2016-06-01

Full Text Available Nowadays, there is a big interest in the use of topical probiotic preparations for skin health. One of the probiotics therurapeutic benefits is used as anti-aging. During aging, there is stimulation of activator protein-1 (AP-1 which is a transcription factor that inhibits the production of collagen and AP-1 supports the breakdown of collagen by enzymes called matrix metalloproteinases (MMPs. As administration of oral Lactobacillus plantarum could inhibit skin aging by lowering the activity of MMP, so the collagen degradation can be derived so probably topical use of Lactobacillus plantarum may give more prominent effects. We used 24 male rats Sprague-Dawley strain as research objects. This study was divided into two groups, the treatment and control groups. The shaved dorsal skin of rats were irradiated with UVB three times a week for 4 weeks with total irradiation dose of 840 mJ/cm2. Skin cream, containing 247.27x107 CFU non-replicating Lactobacillus plantarum FNCC 0020, was smeared on the treatment group, two times daily, whereas the control group did not receive any treatment. Skin biopsies were done at the end of the study for examination of MMP-13 and collagen III expressions. Intensity, distribution, and histoscore of MMP-13 between the treatment and the control group showed no significant difference (p>0.05. The treatment group showed a significant different in the intensity of collagen III with the density distribution of 20–50% and the highest density was 80% (p<0.01. Administration of topical cream L. plantarum FNCC 0020 increased the expression of collagen III density distribution, but not the MMP-13 expression.

An electron spin resonance study of some gamma-irradiated fruits

International Nuclear Information System (INIS)

Maloney, D.R.; Tabner, B.J.; Tabner, V.A.

1992-01-01

The ESR spectra of the seeds, skins and stalks of unirradiated and γ-irradiated Chilean white grapes have been obtained and the results compared to those previously reported for Cape black grapes. The high degree of reproducibility of the spectra obtained from the stalks of different varieties of grapes suggest that ESR spectroscopy could form the basis of a viable test to determine their irradiation history. The condition of the stalk prior to irradiation has been found to have little effect on the resulting spectra. The spectra from the stalks, skins and seeds of unirradiated and γ-irradiated apples, pears and cherries have also been examined. Although most of the spectra from irradiated components exhibit extra features, they are sometimes short-lived and restrict the development of ESR as a viable test. (author)

Effects of irradiation on the anterior pituitary of young rats

International Nuclear Information System (INIS)

Kiriishi, Reijiro; Tsunoda, Shigeru; Sakaki, Toshisuke; Yoshimura, Hitoshi; Ohishi, Hajime; Okamoto, Shingo; Tsujii, Tadasu

1994-01-01

We examined irradiation-induced damage to the anterior pituitary of young rats, particularly to the folliculo-stellate (F-S) cells. The whole brain of 3-week-old Wistar rats (n=24), was irradiated once with a linear accelerator (Linac). The pituitary gland was removed after sacrifice and fixed in formalin. Pituitary specimens were stained with hematoxylin and eosin (H and E), or immunostained for S-100 protein, growth hormone (GH), and adrenocorticotropic hormone (ACTH) by the ABC technique. Angiogenesis in the chronic stage after irradiation was related to an increase of F-S cells in the subacute stage. The decrease in GH cells and ACTH cells after irradiation was dose-dependent, with more severe irradiation-induced damage being in GH cells than in ACTH cells. (author)

Hypoandrogenism related to early skin wound healing resistance in rats.

Science.gov (United States)

Petroianu, A; Veloso, D F M; Alberti, L R; Figueiredo, J A; Rodrigues, F H O Carmo; Carneiro, B G M Carvalho E

2010-04-01

The purpose of this study was to verify the effect of testosterone depletion on healing of surgical skin wounds at different ages and post-operative periods. Forty-four Wistar male rats were divided into four groups: Group 1Y (n = 11) - young control, sham-operated rats (30-day old); Group 1A (n = 10) - adult control, sham-operated rats (3 to 4-month old); Group 2Y (n = 10) - young rats after bilateral orchiectomy; and Group 2A (n = 11) - adult rats after bilateral orchiectomy. After 6 months, a linear incision was performed on the dorsal region of the animals. The resistance of the wound healing was measured in a skin fragment using a tensiometer, on the 7th and 21st post-operative days. The wound healing resistance was higher in Group 1Y than in Group 2Y after 7 days (P Wound healing resistance at 21 days was higher than at 7 days in all groups (P wound healing resistance was not different between young and adult rats. It is concluded that bilateral orchiectomy diminished the wound healing resistance only in young animals at the 7th post-operative day.

Evaluation of freshly irradiated wheat for dominant lethal mutations in Wistar rats

International Nuclear Information System (INIS)

Pawan, S.C.; Aravindakshan, M.; Kumar, N.S.; Subba Rao, V.; Aiyar, A.S.; Sundaram, K.

1977-01-01

Three independent, serially performed experiments involving acute and chronic feeding of freshly irradiated wheat (75 krad, gamma-irradiation) were carried out in Wistar rats. In the first experiment groups of 10 males were given wheat for 1 week; irradiated wheat was consumed by the animals within 24 h of irradiation. In the other two experiments feeding of males was continued for 6 (10 males per group) and 12 (13 males per group) weeks, respectively, and the irradiated wheat was fed within 7 days of irradiation. At the end of each treatment period each male was paired with 3 females for 7 days and sequentially at weekly intervals for 5 or 8 weeks. Females were killed and examined for live and dead implantations and corpora lutea. There were no differences between groups with regard to fertility nor was there any inter-group difference as regards pre- and post-implantation losses whether the rats were fed irradiated or non-irradiated wheat. This suggested that even feeding of freshly irradiated wheat does not induce any dominant lethal mutations in rats

Evaluation of freshly irradiated wheat for dominant lethal mutations in Wistar rats

Energy Technology Data Exchange (ETDEWEB)

Pawan, S C; Aravindakshan, M; Kumar, N S; Subba Rao, V; Aiyar, A S; Sundaram, K [Bhabha Atomic Research Centre, Bombay (India). Bio-medical Group

1977-01-01

Three independent, serially performed experiments involving acute and chronic feeding of freshly irradiated wheat (75 krad, gamma-irradiation) were carried out in Wistar rats. In the first experiment groups of 10 males were given wheat for 1 week; irradiated wheat was consumed by the animals within 24 h of irradiation. In the other two experiments feeding of males was continued for 6 (10 males per group) and 12 (13 males per group) weeks, respectively, and the irradiated wheat was fed within 7 days of irradiation. At the end of each treatment period each male was paired with 3 females for 7 days and sequentially at weekly intervals for 5 or 8 weeks. Females were killed and examined for live and dead implantations and corpora lutea. There were no differences between groups with regard to fertility nor was there any inter-group difference as regards pre- and post-implantation losses whether the rats were fed irradiated or non-irradiated wheat. This suggested that even feeding of freshly irradiated wheat does not induce any dominant lethal mutations in rats.

Electron accelerator technology research in food irradiation

International Nuclear Information System (INIS)

Jin Jianqiao; Ye Mingyang; Zhang Yue; Yang Bin; Xu Tao; Kong Xiangshan

2014-01-01

Electronic accelerator was applied to instead of cobalt sources for food irradiation, to keep food quality and to improve the effect of the treatment. Appropriate accelerator parameters lead to optimal technique. The irradiation effect is associated with the relationship between uniformity and irradiating speed, the effect of cargo size on radiation penetration, as well as other factors that affect the irradiation effects. Industrialization of electron accelerator irradiation will be looked to the future. (authors)

Fine-structural effects of 1200-R abdominal x irradiation on rat intestinal epithelium

International Nuclear Information System (INIS)

Lieb, R.J.; McDonald, T.F.; McKenney, J.R.

1977-01-01

Male Charles River CD rats were shielded from the xiphoid process cranially with lead and were exposed to 1200-R abdominal x irradiation. Animals were sacrificed at 1 through 4 days following irradiation and tissues from both ileum and jejunum were prepared for electron microscopic examination. At the fine-structural level early changes were confined to a proliferation and dilation of smooth endoplasmic reticulum and to an increase in the number of lysosomes. At 4 days postirradiation, cells covering the villi were cuboidal rather than columnar and appeared to be immature crypt-type cells. The appearance of these cells was coincident with the onset of diarrhea in these animals

The response of mouse skin to re-irradiation with x-rays or fast neutrons

International Nuclear Information System (INIS)

Tsukiyama, Iwao; Egawa, Sunao; Kumazawa, Akiyoshi; Iino, Yuu.

1986-01-01

Effects of neutrons and x-rays on mouse skin which had been previously irradiated with x-rays were investigated. Two tattoo marks were placed in the hairless legs of mice at intervals of 15 mm. The legs were exposed to various doses of x-ray and neutrons to determine the relative biological effectiveness (RBE) using the contraction of the skin as an index. The RBE was 0.93 - 1.73. The legs of the mice were preexposed to 25 Gy of x-ray, and exposed 4 months later. The contraction of the skin began earlier than after the first irradiation. RBE was 2.18 - 2.47. This RBE was higher than that in untreated mice. These results suggest that previously irradiated normal tissues are much more sensitive to neutrons than to x-rays. (author)

Alterations in water and electrolyte absorption in the rat colon following neutron irradiation: influence of neutron component and irradiation dose.

Science.gov (United States)

Dublineau, I; Ksas, B; Joubert, C; Aigueperse, J; Gourmelon, P; Griffiths, N M

2002-12-01

To study the absorptive function of rat colon following whole-body exposure to neutron irradiation, either to the same total dose with varying proportion of neutrons or to the same neutron proportion with an increasing irradiation dose. Different proportions of neutron irradiation were produced from the reactor SILENE using a fissile solution of uranium nitrate (8, 47 and 87% neutron). Water and electrolyte fluxes were measured in the rat in vivo under anaesthesia by insertion into the descending colon of an agarose gel cylinder simulating the faeces. Functional studies were completed by histological analyses. In the first set of experiments, rats received 3.8 Gy with various neutron percentages and were studied from 1 to 14 days after exposure. In the second set of experiments, rats were exposed to increasing doses of irradiation (1-4Gy) with a high neutron percentage (87%n) and were studied at 4 days after exposure. The absorptive capacity of rat colon was diminished by irradiation at 3-5 days, with a nadir at 4 days. The results demonstrate that an increase in the neutron proportion is associated with an amplification of the effects. Furthermore, a delay in the re-establishment of normal absorption was observed with the high neutron proportion (87%n). A dose-dependent reduction of water absorption by rat colon was also observed following neutron irradiation (87%n), with a 50% reduction at 3 Gy. Comparison of this dose-effect curve with the curve obtained following gamma (60)Co-irradiation indicates an RBE of 2.2 for absorptive colonic function in rat calculated at 4 days after exposure.

Electron beam irradiating device

Energy Technology Data Exchange (ETDEWEB)

Shinohara, K

1969-12-20

The efficiency of an electron beam irradiating device is heightened by improving the irradiation atmosphere and the method of cooling the irradiation window. An irradiation chamber one side of which incorporates the irradiation windows provided at the lower end of the scanner is surrounded by a suitable cooling system such as a coolant piping network so as to cool the interior of the chamber which is provided with circulating means at each corner to circulate and thus cool an inert gas charged therewithin. The inert gas, chosen from a group of such gases which will not deleteriously react with the irradiating equipment, forms a flowing stream across the irradiation window to effect its cooling and does not contaminate the vacuum exhaust system or oxidize the filament when penetrating the equipment through any holes which the foil at the irradiation window may incur during the irradiating procedure.

Effect of irradiation on the acinar cells of submandibular gland in streptozotocin-induced diabetic rats

International Nuclear Information System (INIS)

Lee, Seung Hyun; Hwang, Eui Hwan; Lee, Sang Rae

2003-01-01

To observe the histologic changes and clusterin expression in the acinar cells of the submandibular gland in streptozotocin-induced diabetic rat following irradiation. Mature Sprague-Dawley rats were divided into three groups: control, diabetic, and diabetic-irradiated groups. Diabetes mellitus was induced in the Sprague-Dawley rats by injecting streptozotocin, while the control rats were injected with citrate buffer only. After 5 days, rats in diabetic-irradiated group were irradiated with single absorbed dose of 10 Gy to the head and neck region. The rats were killed at 1, 3, 7, 14, 21, and 28 days after irradiation. The specimen including the submandibular gland were sectioned and observed using histologic and immunohistochemical methods. Morphologic change of acinar cells was remarkable in the diabetic group, but was not observed in the diabetic-irradiated group. Necrotic tissues were observed in the diabetic-irradiated group. Coloring of toluidine blue stain was most increased at 14 days in the diabetic group, however there were no significant change throughout the period of the experiment in the diabetic-irradiated group. Expression of clusterin was most significant at 14 days in the diabetic group, but gradually decreased with time after 7 days in the diabetic-irradiated group. Degeneration of clusterin was observed in the diabetic-irradiated group. This experiment suggests that the acinar cells of submandibular gland in rats are physiologically apoptosis by the induction of diabetes, but that the apoptosis is inhibited and the acinar cells necrotized after irradiation.

Behavioral changes in rats prenatally irradiated with low dose of gamma-rays

International Nuclear Information System (INIS)

Kiskova, J.; Smajda, B.; Capicikova, M.; Lievajova, K.

2006-01-01

In this work, the effects of prenatal gamma-irradiation on behavior in adult Sprague-Dawley rats were studied. Four months old female rats were irradiated with a dose of 1 Gy of gamma-rays on day 15 of gestation. The offspring of irradiated mothers (n=26) and that of control, non-irradiated mothers (n=36) of both sexes at the age of 3 month were tested in Morris's water maze and in open field test. All experimental groups showed a tendency to shortening the time needed to reach the platform in each trial in Morris water maze. Statistically significant difference between irradiated and control rats was detected only in males on 3 rd experimental day. The ability to remember the position of the platform was not altered in irradiated animals after a 4 day pause. In open field test, statistically significant differences in comparison with controls were detected in number of squares entered and in crossings of the central square (P ≤ 0.05) in males. These findings suggest, when comparing with results of other authors, that irradiation effects on postnatal behavior in rats are extremely dependent on the time point of irradiation and that a correlation exist between the developmental stage of the individual brain structures at time of irradiation and the late behavioral effects. (authors)

Prolonged survival of isolated rat islet allografts pre-irradiated with X-rays

Energy Technology Data Exchange (ETDEWEB)

Kimura, Toshihisa; Note, Masayuki; Nakagawara, Gizo (Fukui Medical School, Matsuoka (Japan)); Kojima, Yasuhiko

1994-04-01

Prior to transplantation of islets, pre-incubation, or pre-irradiation may suppress the immunogenicity of islet cells without suppressing islet function. In the presently described experiments we investigated the use of X-ray irradiation prior to transplantation to reduce islet immunogenicity. To determine whether or not the islet function was reduced after irradiation, ACI rat islets were transplanted into the subrenal capsules of isogeneic rats which had been diabetic and examined the blood glucose level over a period of 40 days. The results indicated that irradiation injury was dose-dependent and that islets irradiated with over 80 Gy lost their function. Next, allogeneic transplantation was performed using the model of ACI rats to Lewis rats without the use of any immunosuppressive agent. Non-irradiated islets were rejected within 7 days. However 20 Gy or 40 Gy irradiated islets prolonged survival (18.7[+-]5.8 days (n=6) and 26.7[+-]10.0 days (n=6), respectively). To determine the basis for this effect, MHC expression of islets was examined by the immunoperoxidase technique. Immunohistologic studies showed that 40 Gy-irradiated islets were depleted of Class II antigen positive cells while Class I antigen expression was unchanged. These results suggest that the prolongation of islets survival by X-ray irradiation may possibly be due to, in part, the depletion of donor Class II antigen positive cells. (author).

Effect of ultraviolet B irradiation on delayed-type hypersensitivity, cytotoxic T lymphocyte activity, and skin graft rejection

International Nuclear Information System (INIS)

Tamaki, K.; Iijima, M.

1989-01-01

The influence of ultraviolet B irradiation on the induction of delayed-type hypersensitivity reactions to alloantigens by epidermal cells (EC), on the generation of cytotoxic T lymphocyte activity to alloantigens, and on skin graft rejection was studied. After the skin was irradiated with UVB in vitro, EC were obtained. The EC were injected subcutaneously, and the DTH reaction was compared with that induced by non-UVB-irradiated EC. A reduction in the DTH reaction was observed (from 62% to 99.1%). CTL activity in these mice was assessed after in vitro stimulation. CTL activity in mice sensitized with UVB-irradiated EC was significantly reduced. Furthermore, mice sensitized with UVB-irradiated EC did not reject a subsequent skin allograft in an accelerated fashion, whereas mice sensitized with non-UVB-irradiated EC did. The mechanism(s) of these reactions and the clinical application of the UVB irradiation prior to grafting are discussed

Inhibition of gluconeogenesis in the perfusing liver of irradiated rats

International Nuclear Information System (INIS)

Borovikova, G.V.; Dokshina, G.A.; Ermakova, G.N.; Mashkova, N.Yu.

1981-01-01

It was shown on the perfusing liver taken from rats on the 1st and 3d days after irradiation in a dose of 18.06x10 -2 C/kg that insulin (400 μunits/ml) and taurine (40 mg%) exerted an inhibiting action on the rate of gluconeogenesi.s and transamination, catalyzed by alanine aminoferase and aspartate aminoferase, in a soluble fraction of the irradiated rat liver. The gluconeogenic capacity and the reactivity of the isolated organ were shown to decrease on the 3d day after irradiation [ru

The effects of irradiation on the mandibular bone of rats on the low calcium diet

Energy Technology Data Exchange (ETDEWEB)

Hwang, Eui Whan; Lee, Sang Rae [Dept. of Oral Radiology, College of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

1992-08-15

The purpose of this study was to investigate the changes of morphology and structure of bone tissue in the irradiated mandibular bone in rats which were fed a low calcium diet. In order to carry out this experiment, 64 seven-week old Sprague- Dawley strain rats weighing about 150gms were selected and equally divided into one experimental group of 32 rats and one control group with the remainder. The experimental group and the group were then subdivided into two groups when the rats reached ten-week old, 16 were assigned rats for each subdivided group, exposed to irradiation. The two irradiation groups received a single dose of 20Gy in the jaws area only and irradiated with a cobalt-60 teletherapy unit. The rats in the control and experimental groups were serially termination, both sides of the dead rats mandibular bodies were removed and fixed with 10% neutral formalin. One side of the mandibular body was radiographed with a soft X-ray apparatus. Thereafter, the obtained microradiographs were observed by a light microscope. The remaining side of the mandibular bone was further decalcified and embedded in paraffin as using the general method. The specimen ectioned and stained with hematoxylin and eosin, and Rabit Anti-Human Tumor Necrosis Factor-{alpha}, observed by a light microscope. The obtained results were as follows: 1. Microradiogram revealed that thinning of the cortex and a decrease in the trabecula of the interradicular bone and mandibular body were observed and noted from the start to finish throughout the experiment in the non-irradiated rats on the low calcium diet rather than in the non-irradiated rats on the normal diet.In microscopic observation, there were marked osteolytic changes in the center of the bone marrow. 2. Microradiogram revealed that thinning of the cortex and a decrease in the trabecula of interradicular bone and mandibular body were more marked after 7 days in the irradiated rats in the low calcium diet rather than in the non-irradiated

Protective effect of gelatin and gelatin hydrolysate from salmon skin on UV irradiation-induced photoaging of mice skin

Science.gov (United States)

Chen, Tiejun; Hou, Hu; Lu, Jiaohan; Zhang, Kai; Li, Bafang

2016-08-01

The objective of this study was to investigate the effect of gelatin (SG) isolated from salmon skin and its hydrolysate (SGH) on photoaging skin, and the mechanism responsible for anti-photoaging. The average molecular weights of SG and SGH were 65 kDa and 873 Da, respectively. The amino acid compositions of SG and SGH were similar. Both of them were abundant in hydrophobic amino acids. Twenty-five peptides were identified from SGH. SG and SGH could improve UV irradiation-induced pathological changes of macroscopical tissue texture and skin morphology. Hydroxyproline content is an indicator of matrix collagen content, SG and SGH could inhibit the decrease of hydroxyproline content in photoaging skin in a dose dependent manner. In addition, SG and SGH could alleviate UV irradiation-induced oxidative damages to skin by increasing the activities of total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), increasing the content of glutathione (GSH) and decreasing the content of malonaldehyde (MDA). Moreover, SG and SGH could enhance immune regulation system by increasing the thymus index. Thus, the anti-photoaging mechanisms of SG and SGH were by inhibiting the depletion of antioxidant defense components, involving in the synthesis of collagen and enhancing the function of immune system. Besides, SGH showed a better result in protecting skin from photoaging than SG.

Effects of electron-beam irradiation to the hydroxyapatite and tricalcium phosphate mixtures for the development of new synthetic bone substitutes

Energy Technology Data Exchange (ETDEWEB)

Kim, Soung Min; Eo, Mi Young; Kang, Ji Young; Park, Jung Min; Seo, Mi Hyun; Myoung, Hoon; Lee, Jong Ho [Seoul National Univ., Seoul (Korea, Republic of); Han, Young Hwan; Lee, Byung Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2010-07-01

The aim of this study is to evaluate the effect and potential of electron beam irradiation treatment to new bone formation and healing in rat calvarial bone defects using hydroxyapatite and tricalcium phosphate mixtures. We used 1.0-2.0 MeV linear accelerator and 2.0 MeV superconductive linear accelerator with different irradiation dose such as 1, 30, 60 kGy. Structural changes in this synthetic bone material were analyzed in vitro, such as SEM, elementary and FE-SEM, ATR-IR, and CSR. And after sterilization with ethylene oxide, we use it as a bone graft material, in vivo. Bilateral, standardized truenesses circular calvarial defects, 7.0 mm in diameter, were created in male Sprague-Dawley rats. In each experimental group, the defect was filled with electron beam irradiated synthetic bony mixtures. Rate were sacrificed 2, 4 and 8 weeks post-op. for radiographic, histomorphologic, immunohistochemical staining, TEM, and elementary analysis.

SU-F-T-248: FMEA Risk Analysis Implementation (AAPM TG-100) in Total Skin Electron Irradiation Technique

Energy Technology Data Exchange (ETDEWEB)

Ibanez-Rosello, B; Bautista-Ballesteros, J; Bonaque, J [Hospital La Fe, Valencia, Valencia (Spain); Perez-Calatayud, J [Hospital La Fe, Valencia, Valencia (Spain); Clinica Benidorm, Benidorm, Alicante (Spain); Gonzalez-Sanchis, A; Lopez-Torrecilla, J; Brualla-Gonzalez, L; Garcia-Hernandez, T; Vicedo-Gonzalez, A; Granero, D; Serrano, A; Borderia, B; Solera, C [Hospital General ERESA, Valencia, Valencia (Spain); Rosello, J [Hospital General ERESA, Valencia, Valencia (Spain); Universidad de Valencia, Valencia, Valencia (Spain)

2016-06-15

Purpose: Total Skin Electron Irradiation (TSEI) is a radiotherapy treatment which involves irradiating the entire body surface as homogeneously as possible. It is composed of an extensive multi-step technique in which quality management requires high consumption of resources and a fluid communication between the involved staff, necessary to improve the safety of treatment. The TG-100 proposes a new perspective of quality management in radiotherapy, presenting a systematic method of risk analysis throughout the global flow of the stages through the patient. The purpose of this work has been to apply TG-100 approach to the TSEI procedure in our institution. Methods: A multidisciplinary team specifically targeting TSEI procedure was formed, that met regularly and jointly developed the process map (PM), following TG-100 guidelines of the AAPM. This PM is a visual representation of the temporal flow of steps through the patient since start until the end of his stay in the radiotherapy service. Results: This is the first stage of the full risk analysis, which is being carried out in the center. The PM provides an overview of the process and facilitates the understanding of the team members who will participate in the subsequent analysis. Currently, the team is implementing the analysis of failure modes and effects (FMEA). The failure modes of each of the steps have been identified and assessors are assigning a value of severity (S), frequency of occurrence (O) and lack of detection (D) individually. To our knowledge, this is the first PM made for the TSEI. The developed PM can be useful for those centers that intend to implement the TSEI technique. Conclusion: The PM of TSEI technique has been established, as the first stage of full risk analysis, performed in a reference center in this treatment.

Biological and physiological changes in rats fed some raw and irradiated legumes

International Nuclear Information System (INIS)

Elwakeil, F.A.; Farag, H.; Sharabash, M.T.M.; Diaa Eldin, M.; Mahrous, S.R.

1995-01-01

Body weight of rats fed on raw kidney beans, soybeans, broad beans, chick peas and lupines suftered from poor growth due to the presence of some anti nutritional factors in these pulses. The processed soybeans, kidney beans, bread beans and lupines at 10 KGy could not correct the growth of rats kept on their diets for 8 weeks while irradiated chick beans at 10 KGy indicating some effect of the irradiation in this respect. When extracts of raw legumes were injected by intraperitoneal route, Ld 5 0 were found to be 125, 300, and 1800 mg/kg, for raw kidney beans, raw soybeans, and raw broad beans respectively. However, injecting the extracts of raw chick peas and raw lupines did not kill the rats even at higher concentration levels of 300 mg/kg. Similar results were obtained with irradiated chick peas and lupines (10 KGy). Meanwhile, post irradiation treatment of kidney beans, soybeans, and broad beans caused the Ld 5 0 to be 250,400, and 2000 mg/kg for the above pulses respectively. Both raw and irradiated kidney beans and raw soybeans were most active in stimulating pancreas and liver growth and reducing spleen weight. Irradiated soybeans showed a moderate, but significant, increase in liver weight only. However, rats which received both raw and irradiated broad beans, chick peas and lupins in their diets did not suffer any pancreatic, liver hypertrophy or spleen atrophy. The hematological parameters investigated showed that there was no significant differences between rat groups fed on either the raw or the irradiated legumes. 5 tabs

Electron beam influence on the carbon contamination of electron irradiated hydroxyapatite thin films

International Nuclear Information System (INIS)

Hristu, Radu; Stanciu, Stefan G.; Tranca, Denis E.; Stanciu, George A.

2015-01-01

Highlights: • Carbon contamination mechanisms of electron-beam-irradiated hydroxyapatite. • Atomic force microscopy phase imaging used to detect carbon contamination. • Carbon contamination dependence on electron energy, irradiation time, beam current. • Simulation of backscattered electrons confirms the experimental results. - Abstract: Electron beam irradiation which is considered a reliable method for tailoring the surface charge of hydroxyapatite is hindered by carbon contamination. Separating the effects of the carbon contamination from those of irradiation-induced trapped charge is important for a wide range of biological applications. In this work we focus on the understanding of the electron-beam-induced carbon contamination with special emphasis on the influence of the electron irradiation parameters on this phenomenon. Phase imaging in atomic force microscopy is used to evaluate the influence of electron energy, beam current and irradiation time on the shape and size of the resulted contamination patterns. Different processes involved in the carbon contamination of hydroxyapatite are discussed

Activation of Peroxisome Proliferator-Activated Receptor Alpha Improves Aged and UV-Irradiated Skin by Catalase Induction.

Science.gov (United States)

Shin, Mi Hee; Lee, Se-Rah; Kim, Min-Kyoung; Shin, Chang-Yup; Lee, Dong Hun; Chung, Jin Ho

2016-01-01

Peroxisome proliferator-activated receptor alpha (PPARα) is a nuclear hormone receptor involved in the transcriptional regulation of lipid metabolism, fatty acid oxidation, and glucose homeostasis. Its activation stimulates antioxidant enzymes such as catalase, whose expression is decreased in aged human skin. Here we investigated the expression of PPARα in aged and ultraviolet (UV)-irradiated skin, and whether PPARα activation can modulate expressions of matrix metalloproteinase (MMP)-1 and procollagen through catalase regulation. We found that PPARα mRNA level was significantly decreased in intrinsically aged and photoaged human skin as well as in UV-irradiated skin. A PPARα activator, Wy14643, inhibited UV-induced increase of MMP-1 and decrease of procollagen expression and caused marked increase in catalase expression. Furthermore, production of reactive oxygen species (ROS) was suppressed by Wy14643 in UV-irradiated and aged dermal fibroblasts, suggesting that the PPARα activation-induced upregulation of catalase leads to scavenging of ROS produced due to UV irradiation or aging. PPARα knockdown decreased catalase expression and abolished the beneficial effects of Wy14643. Topical application of Wy14643 on hairless mice restored catalase activity and prevented MMP-13 and inflammatory responses in skin. Our findings indicate that PPARα activation triggers catalase expression and ROS scavenging, thereby protecting skin from UV-induced damage and intrinsic aging.

A comparison of effects between accelerated heavy ion irradiation and X-irradiation on the development of rat cerebellum

International Nuclear Information System (INIS)

Inouye, Minoru; Hayasaka, Shizu; Murata, Yoshiharu; Takahashi, Sentaro; Kubota, Yoshihisa

1999-01-01

The purpose of this experiment is to compare the effects of 290 MeV/u carbon-ion irradiation and X-irradiation on the development of rat cerebellum. Pregnant rats were exposed to carbon-ion beams at a single dose of 1.5 Gy on day 19.0 of gestation. Other groups of pregnant rats were exposed to X-rays on day 19.0 at single doses of 1.5, 2.0 and 2.5 Gy. Their fetuses were removed 8 hr after exposure, and an acute effect examined microscopically for cell death in the external granular layer of the cerebellum. Other dams were allowed to give birth and rear their litters. The offspring were sacrificed at 6 weeks of age, and their cerebella were examined for foliar malformation. The results showed that the effect of 1.5 Gy carbon-ion irradiation on the development of cerebellum was stronger than that of 1.5 Gy X-irradiation and similar to 2.0-2.5 Gy X-irradiation. (author)

Long-term survival of skin allografts in mice treated with fractionated total lymphoid irradiation

International Nuclear Information System (INIS)

Slavin, S.; Strober, S.; Fuks, Z.; Kaplan, H.S.

1976-01-01

Treatment of recipient Balb/c mice with fractionated, high-dose total lymphoid irradiation, a procedure commonly used in the therapy of human malignant lymphomas, resulted in fivefold prolongation of the survival of C57BL/Ka skin allografts despite major histocompatibility differences between the strains (H-2/sup d/ and H-2/sup b/, respectively). Infusion of 10 7 (C57BL/Ka x Balb/c)F 1 bone marrow cells after total lymphoid irradiation further prolonged C57BL/Ka skin graft survival to more than 120 days. Total lymphoid irradiation may eventually prove useful in clinical organ transplantation

Ultrastructure of rat cerebral vessels 4 months after gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

Iwanowski, L; Ostenda, M

1975-01-01

The purpose of this paper was to check the current opinion that one of the late postirradiation changes is early senility (Maxwell, Kruger, 1964). The postirradiation changes of the brain parenchyma are well known from the literature; therefore our investigation is limited to brain capillaries and their closest vicinity. This paper constitutes a fragment of a larger work on the role of connective tissue in the aging brain. Six Wistar male rats of the same brood, about 3 months old, were irradiated over the whole body with gamma rays. Three rats were exposed to a dose of 400 R and three to 800 R. The chosen doses were the lowest and the highest, provoking brain edema but still not lethal. Four months after the exposure the rats were perfused with 4% glutaraldehyde intracardiacly and decapitated. Brain specimens were taken from frontoparietal cortex, lateral ventricle wall, from corpus callosum and griseum pontis. The samples were routinely handled for ultrastructural studies. Observations were performed under electron microscopes showed that the cerebral vessels of both groups of animals were similar.

Age dependent effects of combined irradiation on lipid peroxidation in rat blood

International Nuclear Information System (INIS)

Mazhul', L.M.; Volykhina, V.E.; Gatsko, G.G.

2000-01-01

It was studied the effects of combined action of external acute gamma-irradiation in dose 1.0 Gy and chronic internal irradiation of cesium 137 (0.8 MBq/kg) on lipid peroxidation system in rat blood. Animals of two aged groups (2 and 6 months old) was investigated. The experiments were conducted on 10, 30, 90 and 180 days after the cessation of cesium 137 injection. Internal irradiation didn't exert influence on lipid peroxidation system in blood. Antioxidant system was activated on 10 days after acute irradiation at 2-months old animals and by 180 days at 6-months ones. In the case of combined irradiation activation of the antioxidant system in blood serum of 2-months old rats in early terms (10 days) possibly supports the invariable level of lipid peroxidation products. At 6-months old rats, on the contrary, the activation of the antioxidant system was not registered, however the content of malonic dialdehyde was increased. Possibly, at 2-months old rats the combined irradiation in early terms stimulates the protective systems of the organism in higher degree than at 6-months old ones

Curcumin Protects Against the Acute Inflammatory Process in Irradiated Rats

International Nuclear Information System (INIS)

El-Ghazaly, M.A.; Nada, A.S.; Hegazy, M.E.; Kenawy, S.A.

2010-01-01

Nutraceuticals that provide medical or health benefits, including prevention and treatment of disease may be advantageous in inflammation and exposure to radiation. The aim of this study was to investigate the potential of curcumin to modulate, counteract or prevent the inflammatory response induced in irradiated and non-irradiated rats using the carrageenan air-pouch model as an acute model. Diclofenac was used as a reference standard non-steroidal anti-inflammatory drug (NSAID). Results indicated that exposure of rats to a single dose of gamma-radiation (6 Gy) before induction of inflammation increased production of prostaglandin E2 (PGE2), tumour necrosis factor-alpha (TNF-alpha) and malondialdehyde (MDA) levels in serum. Blood glutathione (GSH) was shown to be reduced in irradiated animals. Curcumin suppressed the elevated levels of TNF-alpha, PGE2 and MDA and was able to restore blood GSH levels. Reduction in liver contents of copper (Cu), zinc (Zn), selenium (Se) and iron (Fe) was recorded after irradiation of animals before induction of inflammation. Curcumin restored the hepatic concentrations of these trace elements. The present results suggest that irradiation of rats caused marked changes in the inflammatory response while curcumin suppressed the inflammatory response in both irradiated and control animals.

Mechanism of liver lipid accumulation in X-irradiated rat

International Nuclear Information System (INIS)

Aiyar, A.S.; De, A.K.

1978-01-01

The incorporation, both in vivo and in vitro, of 14 C-acetate into hepatic lipids, notably the triglyceride and free fatty acid fractions, is greatly reduced following whole-body irradiation and is indicative of significantly reduced lipogenesis. Irradiation results in a several-fold increase in fatty acid oxidation, by the liver in vitro as well as in the whole animal, during the phase of active hepatic lipid accumulation. Small increases in lipoprotein lipase activity of adipose, immediately following irradiation and up to 24 hours, and the attendant marked fall in adipose lipids are suggestive of increased mobilization of peripheral lipids during the early period. However, in view of the fact that maximum lipid accumulations occurs very much later, inflow of extra-hepatic lipid into liver does not appear to be of major etiological significance. There is three-fold experimental evidence in support of an impairment of trigylceride transport from liver being primarily responsible for the build-up of liver lipids: (I) Triton WR-1339 induced hypertriglyceridemia is totally absent in the irradiated rat during the period when liver lipids increase significantly; (II) the rate of disappearance of radioactivity from pre-labeled hepatic lipids is considerably lower in the irradiated rats; and (III) the irradiated rats show decrease in lipoproteins of liver cell-sap and of serum, the latter being more marked and a lowered synthesis of the lipoproteins, as assessed by labeling of the protein moiety. (orig.) [de

Mechanism of liver lipid accumulation in X-irradiated rat

Energy Technology Data Exchange (ETDEWEB)

Aiyar, A S; De, A K [Bhabha Atomic Research Centre, Bombay (India). Biochemistry and Food Technology Div.

1978-03-01

The incorporation, both in vivo and in vitro, of /sup 14/C-acetate into hepatic lipids, notably the triglyceride and free fatty acid fractions, is greatly reduced following whole-body irradiation and is indicative of significantly reduced lipogenesis. Irradiation results in a several-fold increase in fatty acid oxidation, by the liver in vitro as well as in the whole animal, during the phase of active hepatic lipid accumulation. Small increases in lipoprotein lipase activity of adipose, immediately following irradiation and up to 24 hours, and the attendant marked fall in adipose lipids are suggestive of increased mobilization of peripheral lipids during the early period. However, in view of the fact that maximum lipid accumulations occurs very much later, inflow of extra-hepatic lipid into liver does not appear to be of major etiological significance. There is three-fold experimental evidence in support of an impairment of trigylceride transport from liver being primarily responsible for the build-up of liver lipids: (I) Triton WR-1339 induced hypertriglyceridemia is totally absent in the irradiated rat during the period when liver lipids increase significantly; (II) the rate of disappearance of radioactivity from pre-labeled hepatic lipids is considerably lower in the irradiated rats; and (III) the irradiated rats show decrease in lipoproteins of liver cell-sap and of serum, the latter being more marked and a lowered synthesis of the lipoproteins, as assessed by labeling of the protein moiety.

Total lymphoid irradiation

International Nuclear Information System (INIS)

Anon.

1980-01-01

An outline review notes recent work on total lymphoid irradiation (TLI) as a means of preparing patients for grafts and particularly for bone-marrow transplantation. T.L.I. has proved immunosuppressive in rats, mice, dogs, monkeys and baboons; when given before bone-marrow transplantation, engraftment took place without, or with delayed rejection or graft-versus-host disease. Work with mice has indicated that the thymus needs to be included within the irradiation field, since screening of the thymus reduced skin-graft survival from 50 to 18 days, though irradiation of the thymus alone has proved ineffective. A more lasting tolerance has been observed when T.L.I. is followed by an injection of donor bone marrow. 50% of mice treated in this way accepted allogenic skin grafts for more than 100 days, the animals proving to be stable chimeras with 50% of their peripheral blood lymphocytes being of donor origin. Experiments of a similar nature with dogs and baboons were not so successful. (U.K.)

PROGRESSIVE ALTERATION OF SERUM PROTEINS IN RATS SEVERAL MONTHS AFTER AN ACUTE OR PROTRACTED IRRADIATION

Energy Technology Data Exchange (ETDEWEB)

Ghys, R.; Reuter, A.

1963-06-15

Delayed changes of the serum proteins in male Sprague Dawley rats that survived the acute radiation syndrome were investigated. Doses of Co/sup 60/ gamma ranging from LD/sub O/ to LD/sub 50/ were given to rats six to eight weeks of age. Paper electrophoreses and microdosage of proteins by the buiret method were performed on plasma proteins for 206 rats: 29 with acute irradiation; 73 chronic irradiation; 44 acute irradiation following cold acclimatization; and 80 normal animals. No significant variations in the total serum proteins were found in andy one group. Alpha globulins were found to be slightly above normal in some irradiated rats, but there was no significant variation in the BETA globulin fraction. Gamma globulins showed a marked and consistent increase following irradiation. Thus for observed protein chandges in irradiated rats have not proven to be dose dependent. It is suggested that the changes may provide a link between early irradiation syndrome and late effects. (H.M.G.)

Impairments of learning and memory in the rats after brain irradiation

Energy Technology Data Exchange (ETDEWEB)

Takai, Nobuhiko [National Inst. of Radiological Sciences, Chiba (Japan)

2002-06-01

Clinical trials of hadrontherapy have been carried out world wide at several facilities including National Institute of Radiological Sciences (NIRS). Cerebral dysfunction is one of the major concerns associated with radiotherapy of brain tumors. However, little is known about the neurochemical basis of brain dysfunction induced by proton irradiation. We investigated and reported here the early consequences of brain damages caused by proton beam. The animals that had memorized the location of the standard position were locally irradiated to brain with either 70 MeV protons or 290 MeV carbon ions. At 24 hr after irradiation, impairment of the long-term memory was not observed in the irradiated rats compared to control. Irradiated animals, however, required substantially longer time finding out the standard position than control rats when the standard platform displaced to a position different from memorized position. This follows that a single doses of 30 Gy, either protons or carbon ions, impairs the working memory of animals. Function of muscarinic acetylcholine receptors was analyzed by an in vivo binding assay using radioligand quinuclidinyl benzilate (QNB). Irradiated rats were intravenously injected with 5.5 MBq of {sup 3}H-QNB 24 hr after the irradiation, and decapitated 60 min after tracer injection. The autoradiographic studies showed an transitional increase of {sup 3}H-QNB in vivo binding in the early phase after proton irradiation, even though no change in in-vitro {sup 3}H-QNB binding was see in brain autoradiograms of irradiated rats. The cerebral blood flow and the histrogical features of brain were also changed at 3 months post-irradiation. These results indicate that the memory impairment caused by radiation is closely related to the early change of acetylcholine receptor in vivo. (author)

Impairments of learning and memory in the rats after brain irradiation

International Nuclear Information System (INIS)

Takai, Nobuhiko

2002-01-01

Clinical trials of hadrontherapy have been carried out world wide at several facilities including National Institute of Radiological Sciences (NIRS). Cerebral dysfunction is one of the major concerns associated with radiotherapy of brain tumors. However, little is known about the neurochemical basis of brain dysfunction induced by proton irradiation. We investigated and reported here the early consequences of brain damages caused by proton beam. The animals that had memorized the location of the standard position were locally irradiated to brain with either 70 MeV protons or 290 MeV carbon ions. At 24 hr after irradiation, impairment of the long-term memory was not observed in the irradiated rats compared to control. Irradiated animals, however, required substantially longer time finding out the standard position than control rats when the standard platform displaced to a position different from memorized position. This follows that a single doses of 30 Gy, either protons or carbon ions, impairs the working memory of animals. Function of muscarinic acetylcholine receptors was analyzed by an in vivo binding assay using radioligand quinuclidinyl benzilate (QNB). Irradiated rats were intravenously injected with 5.5 MBq of 3 H-QNB 24 hr after the irradiation, and decapitated 60 min after tracer injection. The autoradiographic studies showed an transitional increase of 3 H-QNB in vivo binding in the early phase after proton irradiation, even though no change in in-vitro 3 H-QNB binding was see in brain autoradiograms of irradiated rats. The cerebral blood flow and the histrogical features of brain were also changed at 3 months post-irradiation. These results indicate that the memory impairment caused by radiation is closely related to the early change of acetylcholine receptor in vivo. (author)

The protective role of damsissa (Ambroosia Maritima) against gamma irradiation in albino rats

International Nuclear Information System (INIS)

Osman, O.A.; Mohamed, Y.S.

2003-01-01

The present work was directed to evaluate the effectiveness of treatment with damsissa (Ambrosia maritima) for thirty consecutive days pre- irradiation exposure in controlling the post-irradiation hazards in irradiated rats. Male albino rats (Spraue Dowley strain) weighing about 120+- 10 g were used and blood samples were collected from tails of animals thirty days after treatment with damsissa and seven days post irradiation. Blood samples were subjected to biochemical analysis such as liver functions, kidney function and lipid profile. Whole body gamma irradiation of rats at 6 Gy (single dose) caused significant decrease in the contents of total proteins accompanied by significant increase of urea level as recorded on the 7th days post irradiation. Data obtained in this study revealed that whole body gamma irradiation induced significant elevation in all tested blood lipid functions. There was significant increase of aspartate amino transferase (AST) and alanine amino transferase (ALT) whole alkaline phosphatase (ALP) showed statistical significant decrease as compared with the control group. Damisissa (Ambrosia maritima) treatment exerted noticeable amelioration in the the studied biochemical parameters of the irradiated albino rats. The mechanism of action of damsissa may be due to its anti-inflammatory properties against whole body gamma irradiation

Biochemical Studies on Rosemary Extracts as an Antioxidant in Irradiated Rats

International Nuclear Information System (INIS)

Abady, M.M.; Zahran, A.M.; Mansour, S.Z.; Ragab, E.A.

2003-01-01

The antioxidant properties of rosemary (Rosmarinus officinalis) essential oil and crude ethanolic extract, have been attributed to its phenolic diterpene, carnosol, carnosic acid, caffeic acid and its derivatives such as rosmarinic acid. These aroma compounds were identified to protect biological membranes from oxidative stress in addition to divers pharmacological and therapeutic activities. This study was undertaken to investigate the effect of natural extract derived from rosemary herb, as an antioxidant defensive element in irradiated rats. Mixture of essential oil and hydroalcoholic extract was orally administered to rats by gavage (150 mg/kg B.w.) for 35 days before exposure to the first fraction of irradiation exposure and during the whole period of irradiation treatment (12 days). Whole body irradiation was delivered as fractionated doses at 1 Gy increment every other day up to total cumulative dose of 6 Gy. Changes in the content of reduced glutathion (GSH), glutathion peroxidase (GSHPx), glucose -6- phosphate dehydrogenase (G-6-PD), superoxide dismutase (SOD) and catalase (Cat.) in blood, liver and spleen were evaluated in different rat groups. The results revealed that transient noticeable increase during the 1st hour post irradiation in the aforementioned parameters, followed by significant decrease recorded after 7 days. Rats supplemented rosemary extract before irradiation have significantly ameliorate the radiation induced depletion in the antioxidant component system

Radioprotective role of vitamin E and urea in irradiated albino rats

International Nuclear Information System (INIS)

Mahdy, A.M.; Elkashef, H.S.

1991-01-01

The present study evaluates the action of vitamin E and urea as chemical radioprotectors for controlling the radiation induced changes in creatine and creatinine levels in the forebrain of female rats subjected to 7 Gy whole body gamma irradiation. The levels of creating and creatinine in the forebrain of normal control rats were±704±22 to±724±23 and 11.053 0.119 to 11.553 0.127 /g fresh tissue; respectively. The applied radiation dose caused a significant increase in the creating level of about 15%, 18%, 13% and 41% on the first,third,seventh and tenth days post irradiation; respectively. At the same post irradiation days, the level of creatinine generally increased, but not to the same extent as creatine. The treatment of rats either with vitamin E or with urea pre radiation exposure caused a remarkable recovery in both creatine and creatinine levels in the forebrain of irradiated rats.The results are discussed in the high of discussed in the high of available literatures. 2 tab

Tissue glycogen and blood glucose in irradiated rats. I

International Nuclear Information System (INIS)

Ahlersova, E.; Ahlers, I.; Paulikova, E.; Praslicka, M.

1980-01-01

Fed and starved (overnight) male rats of the Wistar strain were exposed to whole-body irradiation with 14.35 Gy (1500 R) of X-rays. After irradiation and sham-irradiation all animals were starved until examination performed 1, 6, 24, 48 and 72 h after treatment. The concentration of glucose in the blood and the concentration of glycogen in the liver, heart, skeletal muscle, brown and white adipose tissue were determined. The concentrations of blood glucose and liver glycogen were found to increase between 1 and 6 h after irradiation of the starved animals. The most pronounced increase in glycogen concentration in the liver and heart muscle was observed 24 and 48 h after irradiation. A similar increase in the concentration of blood glucose was found between 48 and 72 h after irradiation. The fed and starved irradiated rats reacted differently, particularly between 48 and 72 h; the liver glycogen concentration decreased in the fed animals and remained elevated in the starved ones. Very high values of terminal glycemia were observed in both groups. The accumulation of glycogen in the heart muscle indicates that this organ is sensitive to ionizing radiation. (author)

Effects of nutritional status on gastric secretion and composition in X-irradiated rat

International Nuclear Information System (INIS)

D'Souza, D.W.; Vakil, U.K.; Sreenivasan, A.

1974-01-01

Whole body x-irradiation of the rat with a sub-lethal (400 r) or lethal (800 r) dose causes a marked depression in secretion and composition of gastric juice with a maximum drop of the 8th day. Similarly, pepsin and gastricsin activities also decline progressively, being lowest on the 8th day post-irradiation. Radiation exposure of the rat also results in a sudden rise in serum and tissue histamine levels which occurs on the 1st day, and returns to normal on the 3rd day post-irradiation. The nutritional status of the animal appears to influence recovery from radiation injury. Rats fed adequate diets with respect to protein and vitamin A prior to irradiation (400 r) recover earlier from radiation injury than deficient animals. The above biochemical changes are associated with gross and severe degeneration of stomach cells in the x-irradiated rat. (author)

Biochemical studies on gamma irradiated male rats fed on whey protein concentrate

International Nuclear Information System (INIS)

Mohamed, N.E; Anwar, M.M.; El-bostany, N.A.

2010-01-01

This study carried out to investigate the possible role of whey protein protein concentrate in ameliorating some biochemical disorders induced in gamma irradiated male rats. Forty eight male albino rats were divided into four equal groups: Group 1 fed on normal diet during experimental period. Group 2 where the diet contain 15 % whey protein concentrate instead of soybean protein . Group 3 rats were exposed to whole body gamma radiation with single dose of 5 Gy and fed on the normal diet. Group 4 rate exposed to 5 Gy then fed on diet contain 15 % whey protein concentrate, the rats were decapitated after two and four weeks post irradiation. Exposure to whole body irradiation caused significant elevation of serum ALT, AST, glucose, urea, creatinine and total triiodothyronine with significant decrease in total protein, albumin and thyroxin. Irradiated rats fed on whey protein concentrate revealed significant improvement of some biochemical parameters. It could be conclude that whey protein concentrate may be considered as a useful protein source for reducing radiation injury via metabolic pathway.

Effect of whole body irradiation on different tissues

International Nuclear Information System (INIS)

Casati, V.; Nardino, A.; Tomassi, I.; Becciolini, A.; Rizzi, M.; Martelli, T.

1979-01-01

The uptake and elimination of 14 C leucine were analysed in controls and in rats irradiated 2 h before injection with 8 Gy whole-body irradiation. Plasma, small intestine, kidney and skin were assayed after homogenization for TCA soluble and insoluble activity curves. In highly differentiated tissues with poor proliferative activity and low protein turnover, the uptake and elimination of the tracer did not appear to be affected by irradiation. In the small intestine differences between control and irradiated animals seemed significant. (Auth.)

Morphological changes in skin tumors caused by pulsed laser irradiation

Energy Technology Data Exchange (ETDEWEB)

Moskalik, K G; Lipova, V A; Neyshtadt, E L

1979-01-01

Morphological changes induced by treating melanomas, basaloma and flatcell skin cancers with a pulsed neodymium laser at 1060 nm, pulse length 1 msec and energy 250 to 500 J/cm/sup 2/, were studied using impressions and scrapings from the affected area. Nuclear pyknosis, nuclear and cellular elongation, vacuolization, frequent complete loss of cytoplasm, particulaly in the zone of direct irradiation, and loss of cellular structure were seen. These dystrophic changes increased with closeness to the zone of direct irradiation, culminating in necrosis. Formed and decomposed blood elements and melanin accumulated in the intracellular spaces, due to disruption of capillaries and small arteries and veins. Fewer and more aggregated melanoblasts were found after melanoma irradiation. Nuclear chromatin fusion, cytoplasmic changes and altered cell shape were observed. Basaloma cells were clustered and elongated after irradiation, with many fibrous structures and loss of cellular elements. Cytoplasmic vacuolization and lysis, bare nuclei, karyolysis, karyorrhexis and karyopyknosis were seen in corneous flat-cell cancer. In the few cases in which malignant cells were found under the scab from the first treatment the procedure was repeated. The morphological changes induced by pulsed laser irradiation are very similar to electrocoagulation necrosis, but are more localized. The ability of low and middle energy lasers to induce thrombosis and coagulation in vascular walls reduced the probability of hematogenic tumor cell dissemination. Cytological examination is highly effective in determining the degree of radical skin cancer healing due to laser treatment. 12 references, 2 figures.

Enzyme release in the skin of mice as an effect of soft X-irradiation

International Nuclear Information System (INIS)

Soltesz, L.

1976-01-01

The shaved skin of 7-8 week old male mice was irradiated locally on the back by doses of 100, 500, 1000, 2000 or 4000 R of soft X-ray. The enzyme activity of the washing solution and of the homogenate of the removed skin, the nitrogen content and the incorporation of 3 H-thymidine were measured immediately after irradiation or 1,2,4,8,16 hours later. The activity of lysosomal enzymes (acid phosphatase, beta-glucuronidase, cathepsine D) increased in the washing solution, whereas in the homogenate no significant change was observed. The maximal values were measured on the second day after irradiation with 1000 R. Tha activity of alkaline phosphatase and leucinaminopeptidase (non-lysosomal enzymes) did not change. Neither was any change observed in the nitrogen content of the skin. The incorporation of 3 H-thymidine considerably decreased. It can be concluded that small doses (500-1000 R) of local X-irradiation damage the membrane of lysosoms and lead to a release of cell destructing enzymes. (L.E.)

Changes in ultrastructure of rat ovaries after early postnatal x-ray irradiation

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, A [Juntendo Univ., Tokyo (Japan). School of Medicine

1975-02-01

Female rats were irradiated with 190R of X-rays at 10 days of age and the ovarian ultrastructures were studied 4 and 7 months after irradiation. Ultrastructural changes were found in germinal epithelial cells, in fibroblasts in the tunica albuginea and in interstitial cells. The germinal epithelial cells exhibited various signs of degeneration but no sign of proliferation. Electron density of their basal part was reduced considerably. Their mitochondria became swollen and free ribosomes were decreased in number. The nuclei often protruded from the free surface of these cells. These cells frequently fragmented and, finally, complete desquamation occurred. The basement membrane became unevently thickened. Nuclei of enlarged fibroblasts in the tunica albuginea became irregularly ellipsoid in shape, and the nuclear envelope was occasionally invaginated. Various cytoplasmic organelles of the fibroblasts were well-developed. Some abnormal invasion of cytoplasm into the nucleus was found in the interstitial cells showing the ultrastructural characteristics of steroid hormone synthesis. Various cytoplasmic roganelles and inclusions invaded into the nuclei of these cells and the nuclear envelope sometimes disappeared locally. These interstitial cells contained a large number of irregular-shaped electron dense mitochondria with vesicular cristae, and numerous dilated vesicles of smooth-surfaced endoplasmic reticulum (SER). The cells of the anovular follicles in the irradiated ovaries resembled, in fine structure, the granulosa cells in normal primary follicles of non-irradiated ovaries. These cells seemed to be less affected by early postnatal irradiation.

Dose controlled low energy electron irradiator for biomolecular films.

Science.gov (United States)

Kumar, S V K; Tare, Satej T; Upalekar, Yogesh V; Tsering, Thupten

2016-03-01

We have developed a multi target, Low Energy Electron (LEE), precise dose controlled irradiator for biomolecular films. Up to seven samples can be irradiated one after another at any preset electron energy and dose under UHV conditions without venting the chamber. In addition, one more sample goes through all the steps except irradiation, which can be used as control for comparison with the irradiated samples. All the samples are protected against stray electron irradiation by biasing them at -20 V during the entire period, except during irradiation. Ethernet based communication electronics hardware, LEE beam control electronics and computer interface were developed in house. The user Graphical User Interface to control the irradiation and dose measurement was developed using National Instruments Lab Windows CVI. The working and reliability of the dose controlled irradiator has been fully tested over the electron energy range of 0.5 to 500 eV by studying LEE induced single strand breaks to ΦX174 RF1 dsDNA.

Dose controlled low energy electron irradiator for biomolecular films

Energy Technology Data Exchange (ETDEWEB)

Kumar, S. V. K., E-mail: svkk@tifr.res.in; Tare, Satej T.; Upalekar, Yogesh V.; Tsering, Thupten [Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005 (India)

2016-03-15

We have developed a multi target, Low Energy Electron (LEE), precise dose controlled irradiator for biomolecular films. Up to seven samples can be irradiated one after another at any preset electron energy and dose under UHV conditions without venting the chamber. In addition, one more sample goes through all the steps except irradiation, which can be used as control for comparison with the irradiated samples. All the samples are protected against stray electron irradiation by biasing them at −20 V during the entire period, except during irradiation. Ethernet based communication electronics hardware, LEE beam control electronics and computer interface were developed in house. The user Graphical User Interface to control the irradiation and dose measurement was developed using National Instruments Lab Windows CVI. The working and reliability of the dose controlled irradiator has been fully tested over the electron energy range of 0.5 to 500 eV by studying LEE induced single strand breaks to ΦX174 RF1 dsDNA.

Electron irradiation effect on single crystal of niobium

International Nuclear Information System (INIS)

Otero, M.P.; Lucki, G.

1984-01-01

The effect of electron irradiation (900 KeV) on gliding dislocations of single crystal Nb with its tensile axe in the [941] orientation was observed for the in-situ deformation in a high voltage electron microscope (HVEM) at Argonne National Laboratory. The experimental was carried out by the 1 hour-electron irradiation with no stress applied. Straight dislocations actuating as sinks for the electron produced defects became helicoidal as the irradiation proceeded. Frenkel pairs were created in Nb for electron energies > = 650 KeV and, as the single vacancies do not undergo long-range migration in Nb at temperatures much below 620 K, the defects that are entrapped by the dislocations are self-interstitials produced by electron displacement. Applying the stress it was possible to observe that modified dislocations did not glide while the dislocations not affected by the irradiation are visibly in movement. This important result explains the neutron and electron-irradiation induced work-hardening effect for Nb that was previously observed. (Author) [pt

Mitochondrial activity assessed by cytofluorescence after in-vitro-irradiation of primary rat brain cultures

International Nuclear Information System (INIS)

Cervos-Navarro, J.; Hamdorf, G.

1993-01-01

Mitochondria play a key role in cell homeostasis and are the first cell organells affected by ionizing irradiation, as it was proved by previous electron microscopic investigations. In order to observe functional parameters of mitochondria after low-dose irradiation, primary rat brain cultures (prepared from 15-day-old rat fetuses) were irradiated from a 60 Co-source with 0.5 and 1 Gy at the age of 2 or 7 days in vitro (div). Cytofluorescence measurement was made by a Cytofluor trademark2350 using Rhodamine 123. This fluorescent dye is positively charged and accumulates specifically in the mitochondria of living cells without cytotoxic effect. Since its retention depends on the negative membrane potential as well as the proton gradient that exists across the inner mitochondrial membrane, Rhodamine 123 accumulation reflects the status of mitochondrial activity as a whole. After irradiation with 0.5 and 1 Gy on day 2 in culture there was a decrease in Rhodamine uptake in the irradiated cultures during the first week after the irradiation insult which reached minimum values after 3 days. Rhodamine uptake increased during the following period and finally reached the values of the control cultures. In the second experiment with irradiated cultures on day 7 and the same doses of 0.5 and 1 Gy the accumulation of Rhodamine decreased only initially then increased tremendously. After both doses values of Rhodamine-accumulation were higher than the control level. The results demonstrated that irradiation caused a change in mitochondrial activity depending on the time of irradiation. The dramatic increase over the control levels after irradiation on day 7 in vitro is attributed to the fact that at this time synapses have already developed. Deficiency of mitochondrial activity as well as hyperactivity and the consequent change in energy production may lead to changes in neuronal metabolism including an increase in production of free radicals

Influence of hypoandrogenism in skin wound healing resistance in rats

Directory of Open Access Journals (Sweden)

Denny Fabrício Magalhães Veloso

2009-03-01

Full Text Available Objective: The objective of the present study is to verify the effect of testosterone depletion on healing of surgical skin wounds at different ages and postoperative times. Methods: Forty-four Wistar male rats were divided into four groups: Group 1y (n = 11 – young control, sham-operated rats (30 days-old; Group 1A (n = 10 – adult control, sham-operated rats (three to four months old; Group 2Y (n = 10 – young rats after bilateral orchiectomy; and Group 2A (n = 11 – adult rats after bilateral orchiectomy. After six months, a linear incision was performed on the dorsal region of the animals. The resistance of the wound healing was measured in a skin fragment with a tensiometer, on the 7th and 21st postoperative days. Rresults: The wound healing resistance was higher in Group 1Y than in Group 2Y after seven days (p < 0.05. Wound healing resistance at 21 days was higher than at seven days in all groups (p < 0.05. Late wound healing resistance was not different between young and adult rats. Cconclusions: Bilateral orchiectomy decreased the wound healing resistance only in young animals at the seventh postoperative day.

Effect of Dietary Supplementation by Irradiated Full-Fat Rapeseed on Biochemical Changes in Rats

International Nuclear Information System (INIS)

Farga, D. M. H.; El-Shennawy, H. M.; Soliman, N.A.

2000-01-01

Supplementation of 230 gk 1 of raw and irradiated full-fat rapeseed at 20 kGy in the food of male albino rats for ten weeks of age, caused significantly lower total plasma protein concentration as compared with those fed control diet, heated seeds and seeds irradiated at 50 and 70 kGy diets. On the other hand, the highest total plasma protein value was obtained from the control group flowed in descending order by heated and seeds irradiated at 70 kGy, and 50 kGy. Plasma albumin decreased significantly in rats fed either raw or rapeseed irradiated at 20 and 50 kGy as compared with rats fed control diet, heated or irradiated rapeseed at 70 kGy diets. The same result was observed with plasma globulin and A/G ratio. Supplementing the diet of rats with raw and irradiated rapeseed at 20 and 50 kGy caused significantly higher plasma transaminases activities (GOT and GPT) as compared with those fed control diet, heated or rapeseed irradiated at 70 kGy. However, rats fed raw and rapeseed irradiated at 20 kGy caused a significant increase in alkaline phosphatase as compared with those fed control diet, heated or irradiated seeds at 50 or 70 kGy diets. Moreover, there was no significant discrepancy between groups fed heated seed and seeds irradiated at 50 or 70 kGy as compared with those fed control diets. Level of plasma creatinine was significantly higher in groups of rats fed row and irradiated seeds at 20 kGy as compared with those fed heat processed and irradiated seeds at 50 kGy and 70 kGy and control diets. The results confirm that the applied radiation doses are insufficient enough to bring a complete detoxification of processed seeds. Increasing the applied radiation doses might be be beneficial in this respect

Biochemical response of skin-coated citrus fruits irradiated for preservation

International Nuclear Information System (INIS)

Ahmed, E.S.

1977-01-01

Orange fruits (citrus Sinensis) Kind Egyptian Balady variety, were irradiated for 100, 200 and 400 Krad γ-ray doses in combination with sodium orthophenylphenate, 0.0025% incorporated in wax coatings as preirradiation treatment. The data revealed the utility of combined treatment to control postharvest decay in citrus fruits. 100 Krad extend shelflife of skin-coated fruits by 15 weeks without significant losses in Vitamin C, reducing sugars, or free amino acids and without storage disorders. Unirradiated non skin-coated and unirradiated skin-coated had a shelf-life of 7, and 10 weeks, respectively, under the same experimental storage conditions (14-20 C and R.H. 65-75%)

Intestinal metaplasia induced by x-irradiation in rat

International Nuclear Information System (INIS)

Watanabe, Hiromitsu; Terada, Yoritaka; Fujii, Isao; Yamamoto, Yukiko; Takizawa, Shoichi

1978-01-01

Total 400 rad of x-ray was given in 100 or 150 rad doses to the whole body of rats at intervals of one week, and one year and a half later, rats were killed. Disaccharidase was formed in most of animals, intestinal metaplasia only with goblet cells occurred in 65% of animals, and that with intestinal type of lacuna occurred in 36% of them. When 500 rad of x-ray was irradiated to each part of stomach day after day up to the total dose of 3,000 rad, biochemical intestinal metaplasia already occurred one week after the irradiation, and intestinal type lacuna occurred 2 months after the irradiation. Intestinal type lacuna was recognized in all animals killed 499 days after the irradiation, and intestinal metaplasia with Paneth's cells occurred in 6 out of 11 cases (56%). When a dose of 1,000 rad was irradiated to stomach three times at intervals of 2 days up to the total of 3,000 rad, much intestinal type lacuna was recognized 2 months after the irradiation, gastric adenoid cancerous changes appeared 4 months after, and gastric adenoid cancer occurred 6 months after. The above-mentioned results clarified that even if x-ray of a small dose was irradiated, intestinal metaplasia occurred, and that the period from the irradiation to occurrence of intestinal metaplasia was shortened by increasing a dose of x-ray. It was also clarified that not only intestinal metaplasia but also gastric adenoic cancer occurred due to a great amount of x-ray irradiation. (Ueda, J.)

Intestinal metaplasia induced by x-irradiation in rat

Energy Technology Data Exchange (ETDEWEB)

Watanabe, H; Terada, Y; Fujii, I; Yamamoto, Y; Takizawa, S [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology

1978-04-01

Total 400 rad of x-ray was given in 100 or 150 rad doses to the whole body of rats at intervals of one week, and one year and a half later, rats were killed. Disaccharidase was formed in most of animals, intestinal metaplasia only with goblet cells occurred in 65% of animals, and that with intestinal type of lacuna occurred in 36% of them. When 500 rad of x-ray was irradiated to each part of stomach day after day up to the total dose of 3,000 rad, biochemical intestinal metaplasia already occurred one week after the irradiation, and intestinal type lacuna occurred 2 months after the irradiation. Intestinal type lacuna was recognized in all animals killed 499 days after the irradiation, and intestinal metaplasia with Paneth's cells occurred in 6 out of 11 cases (56%). When a dose of 1,000 rad was irradiated to stomach three times at intervals of 2 days up to the total of 3,000 rad, much intestinal type lacuna was recognized 2 months after the irradiation, gastric adenoid cancerous changes appeared 4 months after, and gastric adenoid cancer occurred 6 months after. The above-mentioned results clarified that even if x-ray of a small dose was irradiated, intestinal metaplasia occurred, and that the period from the irradiation to occurrence of intestinal metaplasia was shortened by increasing a dose of x-ray. It was also clarified that not only intestinal metaplasia but also gastric adenoic cancer occurred due to a great amount of x-ray irradiation.

Early postnatal x-irradiation of the hippocampus and discrimination learning in adult rats

International Nuclear Information System (INIS)

Gazzara, R.A.; Altman, J.

1981-01-01

Rats with X-irradiation-produced degranulation of the hippocampal dentate gyrus were trained in the acquisition and reversal of simultaneous visual and tactile discriminations in a T-maze. These experiments employed the same treatment, apparatus, and procedure but varied in task difficulty. In the brightness and roughness discriminations, the irradiated rats were not handicapped in acquiring or reversing discriminations of low or low-moderate task difficulty. However, these rats were handicapped in acquiring and reversing discriminations of moderate and high task difficulty. In a Black/White discrimination, in which the stimuli were restricted to the goal-arm walls, the irradiated rats were handicapped in the acquisition (low task difficulty) and reversal (moderate task difficulty) phases of the task. These results suggest that the irradiated rats were not handicapped when the noticeability of the stimuli was high, irrespective of modality used, but were handicapped when the noticeability of the stimuli was low. In addition, these results are consistent with the hypothesis that rats with hippocampal damage are inattentive due to hyperactivity

Effects of environmentally differential rearing upon maze performance in prenatally irradiated microcephalic rats

International Nuclear Information System (INIS)

Seo, M.L.; Inouye, M.; Kiyono, S.; Shibagaki, M.

1982-01-01

Pregnant rats received 100 rads of X-irradiation on day 17 of gestation. Control pregnant rats were sham-irradiated on the same gestation day. The male offspring were reared under environmentally enriched, standard colony, and impoverished conditions for 30 days after weaning. Then the Hebb-Williams maze test was carried out. All the prenatally X-irradiated rats were microcephalic: their mean cerebral wet weight was 15.5% less than controls. The effect of X-irradiation was not significant in error scores and running times, whereas the effect of environment was significant in these items; initial and total error scores and running times were decreased in enriched groups compared to impoverished groups in controls as well as in X-irradiated animals

Caspase-3 activation and DNA damage in pig skin organ culture after solar irradiation.

Science.gov (United States)

Bacqueville, Daniel; Mavon, Alain

2008-01-01

In the present study, a convenient and easy-to-handle skin organ culture was developed from domestic pig ears using polycarbonate Transwell culture inserts in 12-well plate. This alternative model was then tested for its suitability in analyzing the short-term effects of a single solar radiation dose (from 55 to 275 kJ.m(-2)). Differentiation of the pig skin was maintained for up to 48 h in culture, and its morphology was similar to that of fresh human skin. Solar irradiation induced a significant release of the cytosolic enzymes lactate dehydrogenase and extracellular signal-related kinase 2 protein in the culture medium 24 h after exposure. These photocytotoxic effects were associated with the formation of sunburn cells, thymine dimers and DNA strand breaks in both the epidermis and dermis. Interestingly, cell death was dose dependent and associated with p53 protein upregulation and strong caspase-3 activation in the basal epidermis. None of these cellular responses was observed in non-irradiated skin. Finally, topical application of a broad-spectrum UVB + A sunfilter formulation afforded efficient photoprotection in irradiated explants. Thus, the ex vivo pig ear skin culture may be a useful tool in the assessment of solar radiation-induced DNA damage and apoptosis, and for evaluating the efficacy of sunscreen formulations.

Responses of vibrissa-sensitive cortical neurons in normal and prenatally x-irradiated rat

International Nuclear Information System (INIS)

Ito, M.; Kawabata, M.; Shoji, R.

1979-01-01

Rats were irradiated by 200 R of x ray on day 17 of gestation through the body wall of the mother. When they underwent the following electrophysiological tests at the age of 3 to 4 month, the somatosensory cortex showed a lack of layers II, III, IV, and Va. Spike responses to quick whisker deflections were recorded from single cells in the somatosenory cortex of normal and prenatally x-irradiated rats. For the irradiated rats the response latency was prolonged when compared to the normal controls. Cortical laminar analysis of field potentials revealed that there was no difference in the latency of these potentials between the two groups, suggesting that vibrissal sensory signals reach the cortical level normally even in the irradiated rats. The prolonged latency of the irradiated cortical neuronal response could thus be ascribed to an abnormal intracortical delay, which was most likely associated with the failure of development of layer IV stellate cells in these preparations

Modeling and simulation of heat distribution in human skin caused by laser irradiation

NARCIS (Netherlands)

Luan, Y.; Dams, S.D.

2009-01-01

Study of light-based skin rejuvenation needs prospective insights of mechanism of laser tissue interaction. A well-built model plays a key role in predicting temperature distribution in human skin exposed to laser irradiation. Therefore, it not only provides guidance for in vitro experiment, but

Mechanism of chromatin degradation in thymocytes of irradiated rats

International Nuclear Information System (INIS)

Zotova, R.N.; Umanskij, S.R.; Tokarskaya, V.I.

1983-01-01

A biphase change in poly (ADP-ribose) polymerase activity of the thymocyte chromatin was observed after 10 Gy irradiation of rats: during the first minutes the incorporation of 14 C-NAD increased by 40% then started decreasing to make 110, 60 and 35% after 1, 2 and 3 h, respectively. Irradiation of rat thymus chromatin in vitro sharply decreased poly (ADP-ribose) polymerase activity. The possible role of changes in the poly (ADP-ribose) synthesis in the activation of nuclear Ca/Mg-dependent endonuclease and in the postirradiation degradation of the thymocyte chromatin is discussed

Characterization of Ninjurin and TSC22 induction after X-irradiation of normal human skin cells

International Nuclear Information System (INIS)

Koike, Manabu; Ninomiya, Yasuharu; Koike, Aki

2008-01-01

The skin is an external organ that is most frequently exposed to radiation. It is important to elucidate the influence of radiation exposure on the skin at the molecular level. To identify radiation-responsive genes in human skin cells, we used microarray technology to examine the effects of irradiation on 641 genes in normal human epidermal keratinocytes at 4 h and 8 h postirradiation with a cytotoxic dose of X-ray (10 Gy). We found that 18 genes were upregulated and 35 genes were downregulated in keratinocytes at 4 h and/or 8 h postirradiation. Ninjurin, whose function remains unknown in keratinocytes, was induced most strongly by X-irradiation. Several known apoptosis-related genes, such as TSC22, were also upregulated. We characterized Ninjurin and TSC22 induction after X-irradiation of normal human skin cells. The induction of the expression of Ninjurin and TSC22 mRNA in keratinocytes following high-dose X-irradiation was confirmed by northern blot analysis. In dermal fibroblasts, Ninjurin, but not TSC22, was induced after X-ray irradiation. The dependence of both gene expression on the status of an apoptosis regulator, p53, was found. In addition, the expression of both mRNA was induced upon treatment with an apoptosis inducer, etoposide. On the other hand, TSC22, but not Ninjurin, was induced and accumulated in keratinocytes upon treatment with an apoptosis inducer, anisomycin. However, in transient expression assay, EYFP-TSC22, as well as EYFP-Ninjurin or EYFP alone, did not induce apoptosis in keratinocytes in contrast to EYFP-GADD45. Taken together, these findings have important implications on the understanding of the mechanism underlying the complex response of skin cells following X-irradiation. (author)

The effects of irradiation on the periodontal tissues of rats with the low calcium diet

International Nuclear Information System (INIS)

Choi, Mun Cheol; Lee, Sang Rae

1992-01-01

The purpose of this study was to investigate the changes of periodontal tissues in the irradiated mandibular bone in rats which were fed normal diet and low calcium diet. In order to carry out this experiment, 64 seven-week old Sprague-Dawley strain rats weighing about 150 gms were selected and equally divided into one experimental group of 32 rats and one control group with the remainder. The experimental group and the control group were then subdivided into two groups when the rats reached the age of 10 weeks, 16 rats were allotted for each subdivided group was composed of 16 rats and exposed to irradiation. The two groups were irradiated a single dose of 20 Gy on the only jaw area and irradiated with a cobalt-60 teletherapy unit. The rats in the control and experimental groups were warily dissected by fours on the 3rd, 7th, the 14th, and the 21st day after irradiation. After each dissection, both sides of the dead rat mandibular bodies were removed and fixed with 10% neutral formalin. The specimens sectioned and observed in histopathological, histochemical, and immunocellular chemical methods. The obtained results were as follows: 1. In the mandibles of rats with low calcium diet the increased number of fibroblasts of periodontal ligaments, many small capillaries and irregular arrangement of loose collagen fibers were detected and the partial resorption of dentin and cementum could be found by the microscopic studies. 2. In the group of irradiated rats, deaerated periodontal tissues led to the condition of irregular arrangement of collagen fibers and the decreased number of fibroblasts. But this condition was somewhat restored after 21 days of experiment. 3. Periodontal tissues of the irradiated rat group with low calcium diet were destroyed earlier than those of the irradiated rat group with normal diet. Soon this condition was restored and then high cellularity and dense collagen fibers were observed. 4. Many periodontal cells bearing tumor necrosis factor

Amelioration of some biochemical parameters in irradiated male albino rats by garlic

International Nuclear Information System (INIS)

El-masry, F.S.H.; El-sayed, N.M.; Hussein, A.H.

2005-01-01

Garlic extract has various medical effects on the treatment of many diseases as hypertension, atherosclerosis, inflammation and diabetes. The alteration of the biochemical parameters in blood serum of irradiated rats may play an important role in determining the pathogenesis of radiation exposure. Many of the damaging effects of ionizing radiation are mediated by reactive free radicals. This study was designed to evaluate the protective role of garlic against gamma irradiation (5Gy) induced biochemical disorders in rats. Samples were collected at 1, 7 and 14 days post-irradiation. Lipid peroxide content (malondialdehyde), cholesterol, HDL-C, LDL-C, fatty acids, glucose, insulin, glycogen, haemoglobin, ferritin andiron were estimated.Garlic was orally administered to rats (100 mg/kg body weight) for 14 days before exposure to single dose of gamma irradiation at dose level 5 Gy. The data revealed significant increase in the levels of lipid peroxide, cholesterol, LDL-cholesterol, fatty acids, insulin, glucose and iron accompanied with significant decrease in the levels of HDL-cholesterol, glycogen, haemoglobin and ferritin due to radiation exposure. Administration of garlic alone to the rats caused nonsignificant changes in the estimated parameters indicating its safe use, but the treatment with garlic to rats before radiation exposure ameliorated the changes induced by gamma irradiation and tended to normalize their levels.It could be concluded that garlic administration may has a beneficial role in restoring the biochemical disorders induced by 5 Gy gamma irradiation

Effects of radiation on the skin blood volume pulse in humans

Energy Technology Data Exchange (ETDEWEB)

Zanelli, G D [Mount Vernon Hospital, Northwood (UK)

1977-01-01

Measurements have been made of the changes in skin blood volume pulse (BVP) in the irradiated skin of three patients (two female, one male) during and up to 250 days after radiotherapy for malignant disease. The instrumentation comprised a modified commercial finger photo-plethysmograph probe with associated electronics, and a survey of the literature revealed that the consensus of opinion seems to be that the recorded pulsations arise from small 'muscular' arteries and arterioles in the 40 to 300 ..mu..m size range. The results show that, as expected, normal, untreated skin shows sizeable variations in BVP. The BVP of irradiated skin became significantly greater than that of normal skin when a dose of 1000 to 1500 rad has been accumulated. The maximum amplitude of the BVP of the irradiated skin seemed to correlate well with the overall severity of the erythema, but increases in BVP preceded erythema flare-ups. In two patients, elevated BVP were recorded for irradiated areas even when most visual signs of erythema had disappeared. Mild cooling of irradiated and non-irradiated skin had differing effects in the BVP. The measurement of the BVP of irradiated skin is a simple, reliable and completely atraumatic method for investigating vascular damage to superficial tissues in humans.

Electron beam dosimetry for a thin-layer absorber irradiated by 300-keV electrons

International Nuclear Information System (INIS)

Kijima, Toshiyuki; Nakase, Yoshiaki

1993-01-01

Depth-dose distributions in thin-layer absorbers were measured for 300-keV electrons from a scanning-type irradiation system, the electrons having penetrated through a Ti-window and an air gap. Irradiations of stacks of cellulose triacetate(CTA) film were carried out using either a conveyor (i.e. dynamic irradiation) or fixed (i.e. static) irradiation. The sample was irradiated using various angles of incidence of electrons, in order to examine the effect of obliqueness of electron incidence at low-energy representative of routine radiation curing of thin polymeric or resin layers. Dynamic irradiation gives broader and shallower depth-dose distributions than static irradiation. Greater obliqueness of incident electrons gives results that can be explained in terms of broader and shallower depth-dose distributions. The back-scattering of incident electrons by a metal(Sn) backing material enhances the absorbed dose in a polymeric layer and changes the overall distribution. It is suggested that any theoretical estimations of the absorbed dose in thin layers irradiated in electron beam curing must be accomplished and supported by experimental data such as that provided by this investigation. (Author)

Modulation of Immune Disorders Induced-Arthritis in γ- Irradiated Rats

International Nuclear Information System (INIS)

Thabet, N.M.S.

2013-01-01

This study was to evaluate the antioxidant and anti-inflammatory capability of a laboratory preparation mixture Nano Selenium-lovastatin (Lov-Se) against oxidative stress and inflammatory cascade in irradiated and/or adjuvant arthritic rats. The experimental animals were divided into: adjuvant free groups and adjuvant induced groups. Rats were exposed to whole body γ-radiation (2 Gy every 3 days up to total dose of 8 Gy) and received oral administration of 1 ml Lov-Se mixture (≈ 20 mg kg - 1 Lov and 0.1 mg kg - 1 day - 1 Se) for 14 successive days. Animal model of arthritis was organized by subcutaneous injection of complete freund’s adjuvant. The antioxidant parameters (heart GSH-Px, CAT, SOD, XDH, GSH and blood Se), and oxidant markers (heart XO, NO, protein carbonyls and TBARS) and Also, the inflammatory molecules (serum TNF-α, CRP and RF) were determined. In irradiated Lov-Se rats, the results obtained reveals that, TBARS, protein carbonyl, TNF-α, CRP levels, and XO, CAT and SOD activities were significantly ameliorated as compared to irradiated rats. Also, heart GSH, NO levels, XDH, GSH-Px activities and blood Se level were significantly improved. In addition, the administration of Lov-Se to the arthritic and arthritic irradiated rats ameliorates the disturbance occurs in oxidative stress, inflammatory cascades and antioxidant indicators when compared to control rats. In conclusion, the proper administration of Lov-Se mixture might reduce the radiation-induced heart injury via amending the antioxidant molecules and decreasing lipid and protein oxidation. Also, it could be suggested that Lov-Se mixture might posses a considerable anti-inflammatory properties

Effect of irradiation and of cysteamine on rat liver mitochondria

International Nuclear Information System (INIS)

Braquet, Monique.

1979-06-01

The aim of this work was to determine: the effects of a cobalt 60 gamma irradiation received by an animal, the biological repercussions of the preliminary administration of cysteamine to the animal exposed. To this end the amount of damage caused by in vivo irradiation of rats was estimated at three levels: on the whole body; on an important organ, the liver; on a specific organite, the mitochondrion. The methods of investigation used fall mainly within the province of biochemical technology. Studies on the effects of ionizing radiations on rats irradiated for ten days at 900 roentgens showed a generalized attack on the whole system, known as the ''Acute Irradiation Syndrome'' and divisible into three phases: stage one, initial phase involving loss of weight and destruction of the liver. These symptoms appear early and reach a paroxysm on the 4th day after irradiation. Stage two, remission phase (from the 5th to the 8th day) when the weight variations become stabilised. Stage three, last phase, often leading to the death between the 9th and 10th days. During the same 10-day period, on the same irradiated rats, the changes in enzymatic systems were followed in order to estimate the magnitude of peroxidative phenomena within a subcellular particle such as the mitochondrion. The results obtained prove a strong disorganisation of the mitochondrial function [fr

A 20 keV electron gun system for the electron irradiation experiments

International Nuclear Information System (INIS)

Mahapatra, S.K.; Dhole, S.D.; Bhoraskar, V.N.

2005-01-01

An electron gun consisting of cathode, focusing electrode, control electrode and anode has been designed and fabricated for the electron irradiation experiments. This electron gun can provide electrons of any energy over the range 1-20 keV, with current upto 50 μA. This electron gun and a Faraday cup are mounted in the cylindrical chamber. The samples are fixed on the Faraday cup and irradiated with electrons at a pressure ∼10 -7 mbar. The special features of this electron gun system are that, at any electron energy above 1 keV, the electron beam diameter can be varied from 5 to 120 mm on the Faraday cup mounted at a distance of 200 mm from the anode in the chamber. The variation in the electron current over the beam spot of 120 mm diameter is less than 15% and the beam current stability is better than 5%. This system is being used for studying the irradiation effects of 1-20 keV energy electrons on the space quality materials in which the irradiation time may vary from a few tens of seconds to hours

A 20 keV electron gun system for the electron irradiation experiments

Energy Technology Data Exchange (ETDEWEB)

Mahapatra, S.K. [Department of Physics, University of Pune, Pune 411007 (India); Dhole, S.D. [Department of Physics, University of Pune, Pune 411007 (India); Bhoraskar, V.N. [Department of Physics, University of Pune, Pune 411007 (India)]. E-mail: vnb@physics.unipune.ernet.in

2005-01-01

An electron gun consisting of cathode, focusing electrode, control electrode and anode has been designed and fabricated for the electron irradiation experiments. This electron gun can provide electrons of any energy over the range 1-20 keV, with current upto 50 {mu}A. This electron gun and a Faraday cup are mounted in the cylindrical chamber. The samples are fixed on the Faraday cup and irradiated with electrons at a pressure {approx}10{sup -7} mbar. The special features of this electron gun system are that, at any electron energy above 1 keV, the electron beam diameter can be varied from 5 to 120 mm on the Faraday cup mounted at a distance of 200 mm from the anode in the chamber. The variation in the electron current over the beam spot of 120 mm diameter is less than 15% and the beam current stability is better than 5%. This system is being used for studying the irradiation effects of 1-20 keV energy electrons on the space quality materials in which the irradiation time may vary from a few tens of seconds to hours.

Green coffee decontamination by electron beam irradiation

International Nuclear Information System (INIS)

Nemtanu, Monica R.; Brasoveanu, Mirela; Grecu, Maria Nicoleta; Minea, R.

2005-01-01

Microbiological load of green coffee is a real problem considering that it is extremely sensitive to contamination. Irradiation is a decontamination method for a lot of foodstuffs, being a feasible, very effective and environment friendly one. Beans and ground green coffee were irradiated with electron beams up to 40 kGy. Microbial load, rheological behavior, electron paramagnetic resonance (EPR) and visible spectroscopy were carried out. The results show that electron beam irradiation of green coffee could decontaminate it without severe changes in its properties

The effects of tungstate on skin lesions caused by PPD in rats.

Science.gov (United States)

Lee, Sang-Hee; Cho, Hyun-Gug; Lee, Sang-Il

2008-04-01

P-phenylenediamine (PPD) has been used as one of the ingredients in hair dye. The purpose of this study is to investigate the skin toxicity of PPD application in a tungstate-induced xanthine oxidase (XO) deficient animal model. PPD (2.5% PPD in 2% NH4OH) was applied to rat skin (25 mg/16.5 cm2) five times every other day in rats fed a standard diet (SD) or a tungstate supplemented diet (TD). The skin structure in the SD and the TD group was intact, whereas XO activity was not detected in the TD group during experimental periods. Furthermore, there were no differences between the SD and the TD group in dermal reactive oxygen species (ROS) scavenging enzymes. In these experimental conditions, although XO activity was not detected in the applied PPD rats fed a tungstate supplemented diet (PTD) group, it showed more severe tissue damage compared with the applied PPD rats fed a standard diet (PSD) group. In addition, the PTD group showed higher increased rates of ROS scavenging enzyme activity and lipid peroxide (LPO) content, and decreased glutathione (GSH) content than in the PSD group. In conclusion, the increase of PPD dermal toxicity in tungstate-induced XO deficient animals may be due to excessive ROS via ROS imbalance during PPD skin application.

Electron beam irradiation facility for low to high dose irradiation applications

International Nuclear Information System (INIS)

Petwal, V.C.; Wanmode, Yashwant; Verma, Vijay Pal; Bhisikar, Abhay; Dwivedi, Jishnu; Shrivastava, P.; Gupta, P.D.

2013-01-01

Electron beam based irradiation facilities are becoming more and more popular over the conventional irradiator facilities due to many inherent advantages such as tunability of beam energy, availability of radiation both in electron mode and X-ray mode, wide range of the dose rate, control of radiation from a ON-OFF switch and other safety related merits. A prototype experimental facility based on electron accelerator has been set-up at RRCAT to meet the low-dose, medium dose and high-dose requirements for radiation processing of food, agricultural and medical products. The facility can be operated in the energy range from 7-10 MeV at variable power level from 0.05-3 kW to meet the dose rate requirement of 100 Gy to kGy. The facility is also equipped with a Bremsstrahlung converter optimized for X-ray irradiation at 7.5 MV. Availability of dose delivery in wide range with precision control and measurement has made the facility an excellent tool for researchers interested in electron/X-ray beam irradiation. A precision dosimetry lab based on alanine EPR and radiochromic film dosimetry system have been established to characterize the radiation field and precise dose measurements. Electron beam scattering technique has been developed to achieve low dose requirement for EB irradiation of various seeds such as groundnut, wheat, soybeans, moong beans, black gram etc. for mutation related studies. This paper describes various features of the facility together with the dosimetric measurements carried out for qualification of the facility and recent irradiation experiments carried out using this facility. (author)

Repair of radiation-induced DNA damage in rat epidermis as a function of age

International Nuclear Information System (INIS)

Sargent, E.V.; Burns, F.J.

1985-01-01

The rate of repair of radiation-induced DNA damage in proliferating rat epidermal cells diminished progressively with increasing age of the animal. The dorsal skin was irradiated with 1200 rad of 0.8 MeV electrons at various ages, and the amount of DNA damage was determined as a function of time after irradiation by the method of alkaline unwinding followed by S 1 nuclease digestion. The amount of DNA damage immediately after irradiation was not age dependent, while the rate of damage removal from the DNA decreased with increasing age. By fitting an exponential function to the relative amount of undamaged DNA as a function of time after irradiation, DNA repair halftimes of 20, 27, 69, and 107 min were obtained for 28, 100-, 200-, and 400-day-old animals, respectively

Cost evaluation of irradiation system with electron accelerator

International Nuclear Information System (INIS)

Kashiwagi, M.

2003-01-01

The features of electron beam irradiation system using electron accelerator are direct energy pour into the irradiated material, no third material mixture such as catalyst, suitable for mass production and easy operation and maintenance work available. These features can bring the various applications such as cross-linking action, graft polymerization, radical polymerization and others. The selection of electron accelerator ratings is made under consideration of quality, width and thickness of irradiated material, production amount, dose required for reaction and irradiation atmosphere. Especially in a case of irradiation of wire with high insulation material such as polyethylene, the consideration of maximum thickness toward irradiation direction is necessary to avoid the discharge (Lichtenberg discharge) by charged-up electrons inside insulation material. Therefore, the acceleration voltage should be selected to make the maximum penetration larger than maximum irradiation thickness. The actual model case of estimate the irradiation cost was selected that the irradiation object was polyethylene insulated wire up to AWG no.14, irradiation amount was 5,000 km/month, necessary dose was 200 kGy, operation time was 22 d/month and 8 h/day and actual operation efficiency was considered loss time such as bobbin changing as 80%. The selected ratings of electron accelerator were acceleration voltage of 800 kV, beam current of 100 mA and irradiation width of 180 cm with irradiation pulleys stand of 60 turns x 3 lanes. The initial total cost was estimated as 3 M$(US) and operation cost was evaluated as 215 k$(US). Therefore, the irradiation cost of wire was evaluated as 0.0036 $/m. (author)

Hepatic injury after whole-liver irradiation in the rat

International Nuclear Information System (INIS)

Geraci, J.P.; Jackson, K.L.; Mariano, M.S.; Leitch, J.M.

1985-01-01

Radiation-induced hepatic injury in rats, which is characterized by marked ascites accompanied by liver necrosis, fibrosis, and vein lesions, is described in this study. These adverse sequelae are produced within 30 days after irradiation if there is surgical removal of two-thirds of the liver immediately after whole-liver irradiation. The LD/sub 50/30/ day and median survival time after liver irradiation and two-thirds partial hepatectomy is 24 Gy and 17 days, respectively. Death is preceded by reduction in liver function as measured by [ 131 I]-labeled rose bengal clearance. Prior to death, liver sepsis and endotoxemia were detected in most irradiated, partially hepatectomized animals. Pretreatment of the animals with endotoxin and/or antibiotic decontamination of the GI tract resulted in increased survival time, but no irradiated, partially hepatectomized animal survived beyond 63 days. This suggests that sepsis and endotoxemia resulting from the bacteria in the intestine are the immediate cause of death after 30-Gy liver irradiation and partial hepatectomy. It is concluded that the hepatectomized rat model is an economical and scientifically manageable experimental system to study a form of radiation hepatitis that occurs in compromised human livers