Effects Of Whole-body Exposure Research Articles

Genotoxicity of Formaldehyde: Effect of Whole-Body Exposure on Polychromatic Erythrocyte/Normochromatic Erythrocyte Ratio in Male and Female Rats.

Every day, millions of individuals are exposed to formaldehyde (FA) due to its extensive presence and versatile use. Many in vivoand in vitroexperiments revealed that the mechanism of genotoxicity induced by FA exposure is complex yet toxicity upon whole-body exposure (WBE) to FA is less. As teachers, students, and skilled assistants in the health care sectors are also extensively exposed to FA vapors, it might result in genotoxicity. However, the effects of subchronic exposure to FA at low concentrations are not clear. Hence, analysis of the micronucleus (MN) was necessary to study the genetic toxicity triggered by FA in the bone marrow of male and female experimental rats. The present study is a gender- and duration of exposure-based assessment of the geno- and cytotoxicity in bone marrow cells of Wistar rats to study the effect of WBE to 10% FA on polychromatic erythrocytes/normochromatic erythrocytes (PCE/NCE) ratio and micronucleated polychromatic erythrocytes (MnPCE) in experimental rats. The obtained result clearly showed that WBE to FA for 60 days at concentrations between 1 and 1.1 ppm (0, 1, and 1.5 h) induced genotoxic effects in both male and female rats by altering the MnPCE% and significantly increasing the ratio of PCE/NCE (1.07 ± 0.23, 1.20 ± 0.20, 1.22 ± 0.14). The PCE/NCE ratio in male rats was lesser (0.98, 1.12, and 1.18) when compared with female rats (1.17, 1.29, and 1.26) with 0, 1, and 1.5 h exposure, respectively. Thus, the genetic/cellular sensitivity to FA differs among the sexes and also depends on the exposure duration.

Effects of Intermittent and Continuous Magnetic Fields on Trace Element Levels in Guinea Pigs.

Electromagnetic fields (EMFs) can affect living cells due to biochemical changes, followed by changes in levels of trace elements in serum and different organs. This study focuses on the effect of whole body exposure to EMF, presented everywhere in our environment, and on the levels of trace elements in serum, femur, brain, kidney, and liver tissues. The analyses performed on 29 guinea pigs were divided into five groups. Guinea pigs were exposed to a magnetic field of 50Hz of 1.5mT. Groups A and B were exposed to the magnetic field for a period of 4h/day continuously (4h/day) for 4 and 7days, respectively. Groups C and D were exposed to the magnetic field for a period of 4h/day intermittently for 4 and 7days, respectively. Group E animals were enrolled as control. Copper (Cu), zinc (Zn), calcium (Ca), and magnesium (Mg) levels were determined by atomic absorption spectroscopy in serum, femur, brain, kidney, and liver tissues in all guinea pigs. When compared to the control groups, the changes in the levels of Cu in serum samples, femur, and kidney tissues of the treated groups were statistically significant. The same was also true for the levels of Mg in the brain, kidney, and lung tissues. Our results suggest that in vivo continuous and intermittent exposure to EMF may cause disturbances in homeostasis of bioelements. These effects could be important risk factors for toxic effects of EMF, especially in relation to deterioration of bioelements.

Younger rats are more susceptible to the lethal effects of sarin than adult rats: 24 h LC50 for whole-body (10 and 60 min) exposures

Chemical warfare nerve agents (CWNA) inhibit acetylcholinesterase and are among the most lethal chemicals known to man. Children are predicted to be vulnerable to CWNA exposure because of their smaller body masses, higher ventilation rates and immature central nervous systems. While a handful of studies on the effects of CWNA in younger animals have been published, exposure routes relevant to battlefield or terrorist situations (i.e. inhalation for sarin) were not used. Thus, we estimated the 24 h LC50 for whole-body (10 and 60 min) exposure to sarin using a stagewise, adaptive dose design. Specifically, male and female Sprague-Dawley rats were exposed to a range of sarin concentrations (6.2–44.0 or 1.6–12.5 mg/m³) for either 10 or 60 min, respectively, at six different times during their development (postnatal day [PND] 7, 14, 21, 28, 42 and 70). For male and female rats, the lowest LC50 values were observed for PND 14 and the highest LC50 values for PND 28. Sex differences were observed only for PND 42 for the 10 min exposures and PND 21 and 70 for the 60 min exposures. Thus, younger rats (PND 14) were more susceptible than older rats (PND 70) to the lethal effects of whole-body exposure to sarin, while adolescent (PND 28) rats were the least susceptible and sex differences were minimal. These results underscore the importance of controlling for the age of the animal in research on the toxic effects associated with CWNA exposure.

Eight hours of nocturnal 915 MHz radiofrequency identification (RFID) exposure reduces urinary levels of melatonin and its metabolite via pineal arylalkylamine N-acetyltransferase activity in male rats

Purpose: We investigated the effects of whole-body exposure to the 915 MHz radiofrequency identification (RFID) on mela-tonin biosynthesis and the activity of rat pineal arylalkylamine N-acetyltransferase (AANAT).Materials and methods: Rats were exposed to RFID (whole-body specific absorption rate, 4 W/kg) for 8 h/day, 5 days/week, for weeks during the nighttime. Total volume of urine excreted during a 24-h period was collected after RFID exposure. Uri-nary melatonin and 6-hydroxymelatonin sulfate (6-OHMS) was measured by gas chromatography-mass spectrometry (GC-MS) and enzyme-linked immunosorbent assay (ELISA), respectively. AANAT enzyme activity was measured using liquid biphasic dif-13 fusion assay. Protein levels and mRNA expression of AANAT was 14 measured by Western blot and reverse transcription polymerase 15 chain reaction (RT-PCR) analysis, respectively.Results: Eight hours of nocturnal RFID exposure caused a sig-nificant reduction in both urinary melatonin (p = 0. 003) and 6-OHMS (p = 0. 026). Activity, protein levels, and mRNA expres-sion of AANAT were suppressed by exposure to RFID (p < 0. 05).Conclusions: Our results suggest that nocturnal RFID exposure can cause reductions in the levels of both urinary melatonin and 6-OHMS, possibly due to decreased melatonin biosynthesis via suppression of Aanat gene transcription in the rat pineal gland.

Effect of whole-body exposure to the 848.5 MHz code division multiple access (CDMA) electromagnetic field on adult neurogenesis in the young, healthy rat brain

Introduction: Whether exposure to the 848.5 MHz code division multiple access (CDMA) signal affects adult neurogenesis is unclear.Materials and methods: An animal experiment was performed with a reverberation chamber designed as a whole-body CDMA exposure system. Male Sprague-Dawley rats were assigned to three groups (n = 6 per group): Cage-control, sham-exposed, and CDMA-exposed groups. Rats in the CDMA-exposed group were exposed to the CDMA signal at a 2 W/kg whole-body specific absorption rate (SAR) for 1 or 8 h daily, 5 days per week, for 2 weeks. Rats received a single intraperitoneal injection of Bromodeoxyuridine (BrdU) to label proliferative cells daily for the last five consecutive days of CDMA signal exposure. An unbiased stereological method was used to estimate the number of BrdU+ cells in the subventricular zone (SVZ) and dentate gyrus (DG).Results: We found no significant changes in the number of BrdU+ cells in the SVZ or DG in the CDMA-exposed rats, compared with rats in the cage-control and sham-exposed groups (p > 0.05).Conclusion: Our results suggest that exposure to the CDMA signal does not affect neurogenesis in the adult rat brain, at least under our experimental conditions.

Pulsed electromagnetic fields accelerate functional recovery of transected sciatic nerve bridged by chitosan conduit: An animal model study

Introduction: Effect of whole body exposure to pulsed electromagnetic fields (PEMF) on nerve regeneration in a rat sciatic nerve transection model was assessed. Methods: Sixty male white Wistar rats were divided into four experimental groups (n = 15), randomly: In transected group (TC) left sciatic nerve was transected and stumps were fixed in adjacent muscle. In chitosan group (CHIT) the defect was bridged using a chitosan conduit filled with phosphate-buffered saline. In treatment group (CHIT/PEMF) the whole body was exposed to PEMF (0.3 mT, 2 Hz) for 4 h/day within 1–5 days. In normal control group (NC) sciatic nerve was only dissected and manipulated. Each group was subdivided into three subgroups of five animals each and nerve fibers were studied 4, 8 and 12 weeks after surgery. Results: Behavioral, functional, electrophysiological, biomechanical, gastrocnemius muscle mass findings and morphometric indices confirmed faster recovery of regenerated axons in CHIT/PEMF than in CHIT group (p < 0.05). Immunohistochemical reactions to S-100 in CHIT/PEMF were more positive than that in CHIT group. Discussion: Whole body exposure to PEMF improved functional recovery and morphometric indices of sciatic nerve. Detailed mechanism of neuroprotective action remains to be investigated. Conclusion: PEMF combine with chitosan grafting could be considered as an effective, safe and tolerable treatment for peripheral nerve repair in clinical practice.

Multigenerational effects of whole body exposure to 2.14 GHz W-CDMA cellular phone signals on brain function in rats.

The present experimental study was carried out with rats to evaluate the effects of whole body exposure to 2.14 GHz band code division multiple access (W-CDMA) signals for 20 h a day, over three generations. The average specific absorption rate (SAR, in unit of W/kg) for dams was designed at three levels: high (<0.24 W/kg), low (<0.08 W/kg), and 0 (sham exposure). Pregnant mothers (4 rats/group) were exposed from gestational day (GD) 7 to weaning and then their offspring (F1 generation, 4 males and 4 females/dam, respectively) were continuously exposed until 6 weeks of age. The F1 females were mated with F1 males at 11 weeks old, and then starting from GD 7, they were exposed continuously to the electromagnetic field (EMF; one half of the F1 offspring was used for mating, that is, two of each sex per dam and 8 males and 8 females/group, except for all offspring for the functional development tests). This protocol was repeated in the same manner on pregnant F2 females and F3 pups; the latter were killed at 10 weeks of age. No abnormalities were observed in the mother rats (F0 , F1 , and F2 ) and in the offspring (F1 , F2 , and F3 ) in any biological parameters, including neurobehavioral function. Thus, it was concluded that under the experimental conditions applied, multigenerational whole body exposure to 2.14 GHz W-CDMA signals for 20 h/day did not cause any adverse effects on the F1 , F2 , and F3 offspring.

The effects of exposure to 915 MHz radiofrequency identification on cerebral glucose metabolism in rat: A [F-18] FDG micro-PET study

Purpose: We investigated the effect of whole-body exposure to 915-MHz radiofrequency identification (RFID) on rat cortical glucose metabolism by using 18F-deoxyglucose positron emission tomography (FDG-PET).Materials and methods: Male Sprague-Dawley rats were divided into three groups: Cage-control, sham-exposed and RFID-exposed groups. Rats were exposed to the 915-MHz RFID for 8 h daily, 5 days per week, for 2 or 16 weeks. The whole-body average specific absorption rate (SAR) was 4 W/kg for the field of the 915 MHz RFID signal. FDG-PET images were obtained the day after RFID exposure, using micro-PET with a FDG tracer. With a Xeleris functional imaging workstation, absolute values in regions of interest (ROI) in the frontal, temporal and parietal cortexes and cerebellum were measured. Cortical ROI values were normalized to the cerebellar value and compared.Results: The data showed that the relative cerebral glucose metabolic rate was unchanged in the frontal, temporal and parietal cortexes of the 915 MHz RFID-exposed rats, compared with rats in cage-control and sham-exposed groups.Conclusion: Our results suggest that 915 MHz RFID radiation exposure did not cause a significant long lasting effect on glucose metabolism in the rat brain.

Loss of Bone Calcium in Exposure to 50 Hz Magnetic Fields

This study investigates the effect of whole body exposure to magnetic fields on the calcium level of blood and bone in a trial to avoid the liability of osteoporosis, fractures, and delayed union of fractures after exposure to magnetic fields present everywhere in the environment. The procedures of the study included analysis for calcium level in both bone and blood. The procedures were performed on 50 Guinea pigs equally divided into 5 groups. Groups A, B, C, and D were exposed to 50 Hz, 0.2 mT magnetic field for 30 d. Group E animals were the control. Group A was sacrificed immediately after exposure; Group B was left away from the field for 15 d for spontaneous repair; Group C received the drug Centrum dissolved in drinking water for 15 d after exposure to the magnetic field; and Group D received centrum in drinking water during the period of exposure (30 d). After sacrificing all animals, the calcium level in both bone and blood was evaluated. Values of blood analysis revealed significant increase in the blood calcium level in exposed animals compared with the control group (P < 0.002) with excess in Group A. This indicated that the calcium left the bone to the blood. Values of the bone analysis revealed significant decrease in bone calcium concentration level in Group A compared with the control group and improvement in the bone condition in Groups C and D, indicating the role of trace element after the exposure period as a compensatory agent of magnetic field damage and its role during the exposure period as a radio-protecting agent.

Effects of whole body exposure to extremely low frequency electromagnetic fields (ELF-EMF) on serum and liver lipid levels, in the rat

BackgoundThe effects of extremely low-frequency electromagnetic fields (ELF-EMF) on the blood serum and liver lipid concentrations of male Wistar rats were assessed.MethodsAnimals were exposed to a single stimulation (2 h) of ELF-EMF (60 Hz, 2.4 mT) or sham-stimulated and thereafter sacrificed at different times (24, 48 or 96 h after beginning the exposure).ResultsBlood lipids showed, at 48 h stimulated animals, a significant increase of cholesterol associated to high density lipoproteins (HDL-C) than those observed at any other studied time. Free fatty acid serum presented at 24 h significant increases in comparison with control group. The other serum lipids, triacylglycerols and total cholesterol did not show differences between groups, at any time evaluated. No statistical differences were shown on total lipids of the liver but total cholesterol was elevated at 24 h with a significant decrease at 96 h (p = 0.026). The ELF-EMF stimulation increased the liver content of lipoperoxides at 24 h.ConclusionSingle exposures to ELF-EMF increases the serum values of HDL-C, the liver content of lipoperoxides and decreases total cholesterol of the liver. The mechanisms for the effects of ELF-EMF on lipid metabolism are not well understand yet, but could be associated to the nitric oxide synthase EMF-stimulation.

Effect of Whole-Body Exposure to High-Frequency Electromagnetic Field on the Brain Cortical and Hippocampal Activity in Mouse Experimental Model

Evaluation of the direct registration of brain cortical and hippocampal activity during a high-frequency electromagnetic field (HF-EMF) exposure was performed. Experimental procedures were done under general anesthesia (urethane, 20%, 2g/kg i.p.) in Lurcher mutant mice, wild type (healthy littermates) were used as controls. Animals were exposed to the HF-EMF with frequency corresponding to cellular phones (900 MHz). We used of gel electrodes (silicon tubes or glass microcapillary filled with agar) where the connection with classical electrodes was located out of HF-EMF space. ECoG evaluation showed a distinct shift to lower frequency components but clear effect has been observed only in wild type (healthy) mice whereas in Lurcher mutant mice only gentle differences between frequency spectra were found. Measurement of hippocampal rhythmicity showed gentle changes with increase of higher frequencies (i.e. opposite effect than in cortex) and changes in theta oscillations registered from a dentate gyrus and CA1 area in both types of animals (healthy and mutant). These findings support an idea about possible influencing the central nervous system by HF-EMF exposure and support also some recent results about possible health risks resulting from cellular phones use.

Influence of irradiation or thymidine (TdR) on the pattern of 3H-TdR incorporation at each cell position in the crypts of the small intestine of the mouse.

Using autoradiographic methods it was noted that S phase cells at the bottom of the crypts in the small intestine were the most efficient scavengers of exogenous injected thymidine. The efficiency of the incorporation of 3H-TdR (salvage pathway of DNA synthesis) by cells at the crypt base (stem cell zone) was twice as high as for the S phase cells at the top of the crypt (maturing proliferative cells). There were no such position-dependent differences in incorporation of 3H-UdR (de novo pathway of DNA synthesis). Radiation (0.75-5.0 Gy 137Cs gamma-rays) inhibited the incorporation of 3H-TdR very rapidly and this was also cell-position dependent. The cells at the bottom of the crypt were the most affected. The injection of cold thymidine before 3H-TdR changed the pattern of the incorporation of 3H-TdR along the side of the crypt in a very similar way to radiation, and the grain number was decreased predominantly in the cells at lower positions. The possibility of the existence of a regional gradient of endogenous thymidine (reutilization from intestinal sources), and the influence of irradiation on the gradient of thymidine incorporation resulting from direct and abscopal effects of whole body exposure, are discussed.

Local and systemic effect of ultraviolet irradiation (UVB and UVA) on human allergic contact dermatitis

In subjects hypersensitive to nickel we have investigated local and systemic effect of whole body exposure of cumulative suberythema UVB doses as well as solarium-UVA exposure. UVB possesses both locally and systemically a suppressive effect on human allergic contact dermatitis, but UVA has no such effect. The systemic suppressive effect of UVB might be of therapeutic importance in patients with severe chronic dermatitis of the hands when adding this effect to a local suppressive effect. Also, patch testing should not be performed during UVB and/or overt sun exposure.

Chemical Protection against Long-Term Effects of Whole-Body Exposure of Mice to Ionizing Radiation: III. The Effects of Fractionated Exposure to C57B1 Mice

Mice of the C57B1/Cnb strain were exposed to four fractionated doses delivered at weekly intervals (total doses from 4 × 50 to 4 × 375 R). One group of mice received a mixture of radioprotectors. T...

Whole body irradiation on the healing of fresh fractures.

WITH THE addition of the atom bomb to the armamentarium of modern warfare, large numbers of persons may be subjected not only to trauma but also to the effects of whole body x-irradiation. With the exception of experimental work reported in the literature on the effects of local x-rays on fracture healing, we have been unable to find any reports on the effect of whole body exposure to x-rays on the healing of fractures. The purpose of this paper is to report our observations of the effect of whole body x-irradiation on fracture healing in the rat. MATERIALS AND METHODS All of the animals used were albino rats of the Wistar strain, weighing over 150 gm. A dose of 500 r will kill 50% of rats of this strain. They are known to require five to six months' growth to reach maturity, with a 300 gm. maximum weight. The rats

Effects of Whole Body Exposure to Irradiation upon Subsequent Fertility of Male Rabbits

Effects of Whole Body Exposure to Irradiation upon Subsequent Fertility of Male Rabbits

Some Aspects of the Biological Action of X-Rays on Cock Spermatozoa

Previous articleNext article No AccessSome Aspects of the Biological Action of X-Rays on Cock SpermatozoaIgor L. KosinIgor L. Kosin Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Volume 17, Number 3Jul., 1944 Article DOIhttps://doi.org/10.1086/physzool.17.3.30151841 Citations: 17Citations are reported from Crossref Journal History This article was published in Physiological Zoology (1928-1998), which is continued by Physiological and Biochemical Zoology (1999-present). PDF download Crossref reports the following articles citing this article:T. Mann Metabolism of Semen, (Nov 2006): 329–390.https://doi.org/10.1002/9780470122549.ch6G. W. Salisbury, J. R. Lodge Metabolism of Spermatozoa, (Nov 2006): 35–104.https://doi.org/10.1002/9780470124888.ch2R. N. Shoffner, J. S. Otis, L. A. Snyder, K. S. Guise The improbability of irradiated spermatozoa as gene transfer vectors in chickens, Theoretical and Applied Genetics 80, no.22 (Aug 1990): 228–233.https://doi.org/10.1007/BF00224391Kamla K. Pandey, M. Rex Patchell Genetic transformation in chicken by the use of irradiated male gametes, Molecular and General Genetics MGG 186, no.33 (Sep 1982): 305–308.https://doi.org/10.1007/BF00729446D.L. Zartman, N.S. Urquhart, D.W. Francis Production Measurements Affected by X-irradiation of Chicken Semen, Poultry Science 54, no.66 (Nov 1975): 2025–2030.https://doi.org/10.3382/ps.0542025G.C. Harris Fertility of Chickens Inseminated Intraperitoneally with Semen Preserved in Liquid Nitrogen, Poultry Science 47, no.22 (Mar 1968): 384–388.https://doi.org/10.3382/ps.0470384H.M. Hyre, H. Patrick, Karl Nestor The Effect of Irradiated Cock Sperm on Fertility and Hatchability, Poultry Science 43, no.11 (Jan 1964): 121–124.https://doi.org/10.3382/ps.0430121J.E. Brown, G.C. Harris, T.D. Hobbs Effect of Intraperitoneal Insemination on Egg Production and Fertilizing Capacity of Fresh and Frozen Chicken Sperm ,, Poultry Science 42, no.44 (Jul 1963): 810–815.https://doi.org/10.3382/ps.0420810Miroslav Valenta, Jaroslav Koloušek, Josef Fulka The Influence of Ionizing Radiation on Nucleic Acids, Vitality and Fecundating Ability of Male Sexual Cells, International Journal of Radiation Biology and Related Studies in Physics, Chemistry and Medicine 6, no.11 (Jul 2009): 81–91.https://doi.org/10.1080/09553006314550081Erwin Goldberg, Charles Norman The metabolism of ejaculated spermatozoa from the fowl, Journal of Cellular and Comparative Physiology 58, no.22 (Oct 1961): 175–180.https://doi.org/10.1002/jcp.1030580208A. van Tienhoven The metabolism of fowl sperm in different diluents, The Journal of Agricultural Science 54, no.11 (Mar 2009): 67–80.https://doi.org/10.1017/S002185960002147XF.H. Wilcox Effect of the Addition of Carbohydrates after Storage on the Motility and Fertilizing Ability of Chicken Sperm, Poultry Science 38, no.55 (Sep 1959): 1162–1168.https://doi.org/10.3382/ps.0381162G.W. Grigg, F. Skaller A Case of Sterility in the Hen, Poultry Science 37, no.44 (Jul 1958): 954–955.https://doi.org/10.3382/ps.0370954I.L. Kosin Metabolism of Turkey Semen as Affected by the Environment of Donor Birds , ,, Poultry Science 37, no.22 (Mar 1958): 376–388.https://doi.org/10.3382/ps.0370376J.H. Quisenberry, R.L. Atkinson Effect of Whole Body X-Ray Irradiation Upon the Reproductive Performance of White Leghorn Males, Poultry Science 35, no.66 (Nov 1956): 1327–1335.https://doi.org/10.3382/ps.0351327D. Kanazir, M. Errera Action des rayons u.v. sur l'acide adénosine- triphosphorique des spermatozoïdes de grenouille, Biochimica et Biophysica Acta 16 (Jan 1955): 198–202.https://doi.org/10.1016/0006-3002(55)90204-3R. L. Murphree, W. M. Whitaker, J. L. Wilding, J. H. Rust Effects of Whole Body Exposure to Irradiation upon Subsequent Fertility of Male Rabbits, Science 115, no.30003000 (Jun 1952): 709–711.https://doi.org/10.1126/science.115.3000.709