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At least 703 records · Page 39Linked to original sources
PubMed2005

Occupational exposure to ionizing radiation is associated with autoimmune thyroid disease.

CONTEXT: The thyroid gland is a potential target organ for radiation-related damage. OBJECTIVE: The aim of the analysis was to investigate the association between occupational exposure to ionizing radiation and autoimmune thyroid disease (AITD). DESIGN: Our design was the cross-sectional Study of Health in Pomerania. SETTING: The setting was the general community. SUBJECTS: Analyses were performed in a population-based sample of 4299 subjects. Among them, 160 persons reported a history of occupational exposure to ionizing radiation. MAIN OUTCOME MEASURE: AITD was defined as the combined presence of hypoechogenicity in thyroid ultrasound and antithyroxiperoxidase antibodies greater than 200 IU/ml. RESULTS: Females with occupational exposure to ionizing radiation had more often AITD than nonexposed females (10.0 vs. 3.4%; P < 0.05). This association persisted after adjustment for relevant confounders (odds ratio, 3.46; 95% confidence interval, 1.16-10.31; P < 0.05). In males, there were too few subjects who fulfilled the criteria of AITD, but the association between the exposure to radiation and hypoechogenicity of the thyroid gland barely missed statistical significance (odds ratio, 2.20; 95% confidence interval, 0.92-5.26; P = 0.08). In both females and males, subjects who reported a length of exposure of more than 5 yr exhibited the highest risk of the endpoints. CONCLUSIONS: We conclude that occupational exposure to ionizing radiation is related to the risk of AITD. The usage of thyroid protection shields by radiation workers is strongly recommended.

Adult↗
PubMed2006

Simultaneous measurement of nitric oxide (NO) and nitrogen dioxide (NO2) in simulated automobile exhaust using medium pressure ionization-mass spectrometry.

In previous papers we have demonstrated two different, two-color resonance-enhanced multiphoton ionization (REMPI) schemes for the simultaneous measurement of trace amounts (ppbV to pptV) of nitrogen monoxide (NO) and nitrogen dioxide (NO(2)). The goal of this study is to provide a laser ionization-mass spectrometric scheme capable of measuring ppmV to ppthV concentrations of NO and NO(2) within vehicle exhaust containing up to ppthV of aromatic hydrocarbons and a time frame of seconds. Two ionization schemes are used here to measure NO and NO(2) in simulated automobile exhaust with three different sources. REMPI Scheme 1 uses broad-bandwidth light and an effusive source to measure NO (limit of detection (LOD) 300 ppmV), NO(2) (LOD 100 ppmV), and aromatic hydrocarbons (via photoionization) along with fragments (via electron impact). REMPI Scheme 2 uses narrow-bandwidth light and a medium pressure laser ionization (MPLI) source to measure NO (LOD 60 ppmV), NO(2) (LOD 3 ppmV), and fragments (via electron impact). The LOD is determined using 10-second sampling times. A newly developed delayed-ion extraction technique for MPLI is then applied to REMPI Scheme 2, dramatically reducing the electron impact signal, so that only NO and NO(2) are observed. We conclude that Scheme 2 with delayed-electron extraction is best suited for measuring in situ NO and NO(2) within engine exhaust.

Algorithms↗
PubMed1998

Risk of ionizing radiation exposure to children: a subject review. American Academy of Pediatrics. Committee on Environmental Health.

Exposure of children to ionizing radiation most commonly is from the environment, chiefly through cosmic rays and radon, or from medical technology. Medical radiation exposure occurs during diagnosis, therapy, and dental radiography. More is known about the biological effects of exposure to ionizing radiation than to nonionizing radiation from microwaves, radiowaves, and the electrical fields of other electrical appliances. This review applies only to sources of ionizing radiation and does not include the potential risks of indoor radon. The effects on children of ionizing radiation have been studied from war activities and environmental accidents. Protections are mode from that data to help pediatricians evaluate risk from radiation when ordering radiographs.

Adolescent↗
PubMed2003

Bcl2-independent chromatin cleavage is a very early event during induction of apoptosis in mouse thymocytes after treatment with either dexamethasone or ionizing radiation.

We have quantified the emergence of early chromatin breaks during the signal transduction phase of apoptosis in mouse thymocytes after treatment with either ionizing radiation or dexamethasone. Dexamethasone at 1 microM can induce significant levels of DNA breaks (equivalent to the amount induced directly by 7.5 Gy ionizing radiation) within 0.5 h of treatment. The execution phase of apoptosis was not observed until 4-6 h after the same treatment. The presence of the Bcl2 transgene under the control of the p56lck promoter almost completely inhibited apoptosis up to 24 h after treatment, but it had virtually no effect on the early chromatin cleavage occurring in the first 6 h. Ionizing radiation induced chromatin cleavage both directly by damaging DNA and indirectly with kinetics similar to the induction of chromatin cleavage by dexamethasone. The presence of the Bcl2 transgene had no effect on the direct or indirect radiation-induced cleavage in the first 6 h, but after the first 6 h, the Bcl2 gene inhibited further radiation-induced chromatin cleavage. These results suggest that endonucleases are activated within minutes of treatment with either dexamethasone or ionizing radiation as part of the very early signal transduction phase of apoptosis, and prior to the irreversible commitment to cell death.

Animals↗
PubMed2004

Lack of sensitivity of primary Fanconi's anemia fibroblasts to UV and ionizing radiation.

Clinical observations and theoretical considerations suggest some degree of radiosensitivity in Fanconi's anemia (FA), but experimental evidence remains controversial. We tested the sensitivity of primary skin fibroblast cultures from all known FA complementation groups to ionizing radiation and ultraviolet light using conventional cell growth and colony formation assays. In contrast to previous studies, and because FA fibroblasts grow and clone poorly at ambient oxygen, we performed our sensitivity tests under hypoxic cell culture conditions. Fibroblast strains from healthy donors served as negative controls and those from patients with ataxia telangiectasia (AT) and Cockayne syndrome (CS) as positive controls. We observed interstrain variation but no systematic difference in the response of FA and non-FA control fibroblasts to ionizing radiation. After exposure to UV radiation, only complementation group A, G and D2 strains displayed values for colony formation EC50 that were intermediate between those for the negative and positive controls. Because of considerable interstrain variation, minor alterations of the response of individual FA strains to ionizing and UV radiation should be interpreted with caution and should not be taken as evidence for genotype-specific sensitivities of primary FA fibroblasts. All together, our data indicate neither systematic nor major sensitivities of primary FA fibroblast cultures of any complementation group grown under hypoxic cell culture conditions to ionizing or UV radiation.

Cell Division↗
PubMed2005

Gene expression profiles of normal human fibroblasts after exposure to ionizing radiation: a comparative study of low and high doses.

Several types of cellular responses to ionizing radiation, such as the adaptive response or the bystander effect, suggest that low-dose radiation may possess characteristics that distinguish it from its high-dose counterpart. Accumulated evidence also implies that the biological effects of low-dose and high-dose ionizing radiation are not linearly distributed. We have investigated, for the first time, global gene expression changes induced by ionizing radiation at doses as low as 2 cGy and have compared this to expression changes at 4 Gy. We applied cDNA microarray analyses to G1-arrested normal human skin fibroblasts subjected to X irradiation. Our data suggest that both qualitative and quantitative differences exist between gene expression profiles induced by 2 cGy and 4 Gy. The predominant functional groups responding to low-dose radiation are those involved in cell-cell signaling, signal transduction, development and DNA damage responses. At high dose, the responding genes are involved in apoptosis and cell proliferation. Interestingly, several genes, such as cytoskeleton components ANLN and KRT15 and cell-cell signaling genes GRAP2 and GPR51, were found to respond to low-dose radiation but not to high-dose radiation. Pathways that are specifically activated by low-dose radiation were also evident. These quantitative and qualitative differences in gene expression changes may help explain the non-linear correlation of biological effects of ionizing radiation from low dose to high dose.

Cells, Cultured↗
PubMed2006

Biological dosimetry -- cytogenetics findings at persons occupationally exposed to ionizing radiation.

A large number of physical and chemical agents are capable to course chromosomal aberrations. Ionizing radiation is frequent and well known course of chromosomal aberrations. If deoxyribonucleic acid (DNA) is irradiated before synthesis chromosomal-type aberrations are caused. Chromatid-type aberrations are results of DNA damages occurred during or after synthesis. Some of these changes could exist at patients several years after exposition. Biological dosimetry-cytogenetics analysis of persons occupational exposed to ionizing radiation in Federation of Bosnia and Herzegovina have been carried out in "Center for Human Genetics" of Medical Faculty in Sarajevo. In this study we have evaluated cytogenetics findings of persons employed in a zone of radiation. Cytogenetics findings have been demonstrated in allowed limit in 154 (81.1%) examinees, and cytogenetics findings were out of normal values in 36 (18.9%) examinees. The majorities who have been employed in a zone of ionizing radiation were in age group 40-44 (25.3%) and age group 45-49 (24.7%). Radiological technicians (35.7%) were exposed the most to ionizing radiation, than clinical nurse specialists (14.7%), radiologists (11.1), physicians (7.4%) machines technicians (6.3%), pneumologists (4.7%), orthopedists (4.2%) and scrub nurses (4.2%). Biological dosimetry-cytogenetics analysis have been carried out at 108 (56.8%) male and 82 (43.2%) female examinees. The most frequent aberration have been presented with 26.8% in the form of acentric fragments, than chromatid fragments with 21.2%, dicentric chromosomes with 19.5%, gaps with 18.7%, minutes with 12.2% and inter-arm interchanges with 1.6%.

Adult↗
PubMed2001

Comparison of chromosome aberrations in peripheral blood lymphocytes from people occupationally exposed to ionizing and radiofrequency radiation.

The genotoxic effects of occupational exposure to ionizing and non-ionizing radiation were investigated in 25 physicians and nurses working in hospitals and in 20 individuals working at radio-relay stations. Examination was conducted by chromosome aberration analysis of peripheral blood lymphocytes. The data showed that total number of chromosome aberrations in people exposed to ionizing and radio-frequency radiation (4.08 +/- 0.37 and 4.35 +/- 0.5 on 200 scored metaphases, respectively) were almost equally higher than those of non-irradiated subjects. The increase was in proportion to the number of individuals having more that 5-aberration/200 metaphases. Acentric fragments comprised the most frequently seen type of aberration. The average numbers in examined groups (11.8 x 10(-3) and 14.8 x 10(-3) per cell, respectively), were significantly higher than 4.2 x 10(-3), which was observed in controls, unexposed individuals. Dicentric fragments were also frequent (4.8 x 10(-3) and 6.25 x 10(-3), respectively, vs. 0.52 x 10(-3) in control). In contrast, the frequency of chromatid breaks increased only after ionizing radiation (3.8 x 10(-3) vs. 0.26 x 10(-3) in control). A positive correlation between the total number of chromosome aberrations and cumulative 6-years dosage was also found. The data emphasized the dangerous effects of prolonged exposure to both types of radiation and indicated that chromosomal aberration analysis should be obligatory for individuals working at radio-relay stations.

Adult↗
PubMed2004

Potential adverse health effects of low-level ionizing radiation exposure in a hospital setting.

In this study, the authors investigated the short-term (i.e., 1-yr) health effects of low-level occupational and personal exposure to ionizing radiation in a hospital setting. Thyroid function, lung function, platelet count, and leukocyte classification were obtained for 142 ionizing radiation operators. In addition, individual exposure doses were measured. The mean annual cumulative dose in 25 exposed subjects was 6.0 +/- 10.1 millisieverts. The highest exposure ratio among 20 of 41 (49%) radioisotope operators was significantly higher than for other ionizing radiation workers. Abnormal leukocyte counts occurred in 26% of radio-diagnosis operators and 30% of radioisotope operators, compared with 15% for other potentially exposed operators. No significant relative risk was found in subjects with above-background exposures. However, the highly exposed population experienced elevations in thyroid stimulating hormone (adjusted odds ratio [ORa = 2.0; T3 [OR = 1.7]); mononuclear leukocytes (ORa = 2.4); and basophilic leukocytes (ORa = 2.0). Although the authors failed to find short-term health effects in hospital operators exposed annually to less than 6.0 millisieverts of ionizing radiation, additional protection would certainly be prudent for these operators.

Adult↗
PubMed2000

[Secondary ionizing radiation generated by digital and analog coronary cineangiographic equipment: influence of external systems of radiologic protection].

BACKGROUND: Exposure to ionizing radiation is a known hazard of radiological procedures. AIM: To compare the emission of secondary ionizing radiation from two coronary angiographic equipment, one with digital and the other with analog image generation. To evaluate the effectiveness of external radiological protection devices. MATERIAL AND METHODS: Environmental and fluoroscopy generated radiation in the cephalic region of the patient was measured during diagnostic coronary angiographies. Ionizing radiation generated in anterior left oblique projection (ALO) and in anterior right oblique projection (ARO) were measured with and without leaded protections. In 19 patients (group 1), a digital equipment was used and in 21 (group 2), an analog equipment. RESULTS: Header radiation for groups 1 and 2 was 1194 +/- 337 and 364 +/- 222 microGray/h respectively (p < 0.001). During fluoroscopy and with leaded protection generated radiation for groups 1 and 2 was 612 +/- 947 and 70 +/- 61 microGray/h respectively (p < 0.001). For ALO projection, generated radiation for groups 1 and 2 was 105 +/- 47 and 71 +/- 192 microGray/h respectively (p < 0.001). During filming the radiation for ALO projection for groups 1 and 2 was 7252 +/- 9569 and 1671 +/- 2038 microGray/h respectively (p = 0.03). Out of the protection zone, registered radiation during fluoroscopy for groups 1 and 2 was 2800 +/- 1741 and 1318 +/- 954 microGray/h respectively (p < 0.001); during filming, the figures were 15,500 +/- 5840 and 18,961 +/- 10,599 microGray/h respectively (NS). CONCLUSIONS: Digital radiological equipment has a lower level of ionizing radiation emission than the analog equipment.

Adult↗
PubMedDate not supplied

Cell-density dependent effects of low-dose ionizing radiation on E. coli cells.

The changes in genome conformational state (GCS) induced by low-dose ionizing radiation in E. coli cells were measured by the method of anomalous viscosity time dependence (AVTD) in cellular lysates. Effects of X-rays at doses 0.1 cGy--1 Gy depended on post-irradiation time. Significant relaxation of DNA loops followed by a decrease in AVTD. The time of maximum relaxation was between 5-80 min depending on the dose of irradiation. U-shaped dose response was observed with increase of AVTD in the range of 0.1-4 Gy and decrease in AVTD at higher doses. No such increase in AVTD was seen upon irradiation of cells at the beginning of cell lysis while the AVTD decrease was the same. Significant differences in the effects of X-rays and gamma-rays at the same doses were observed suggesting a strong dependence of low-dose effects on LET. Effects of 0.01 cGy gamma-rays were studied at different cell densities during irradiation. We show that the radiation-induced changes in GCS lasted longer at higher cell density as compared to lower cell density. Only small amount of cells were hit at this dose and the data suggest cell-to-cell communication in response to low-dose ionizing radiation. This prolonged effect was also observed when cells were irradiated at high cell density and diluted to low cell density immediately after irradiation. These data suggest that cell-to-cell communication occur during irradiation or within 3 min post-irradiation. The cell-density dependent response to low-dose ionizing radiation was compared with previously reported data on exposure of E. coli cells to electromagnetic fields of extremely low frequency and extremely high frequency (millimeter waves). The body of our data show that cells can communicate in response to electromagnetic fields and ionizing radiation, presumably by reemission of secondary photons in infrared-submillimeter frequency range.

Bacteriolysis↗
PubMed2003

[Matrix-assisted laser desorption ionization].

Since its invention, matrix-assisted laser desorption ionization (MALDI) has found wide application in mass spectrometry of high molecular weight compounds such as synthetic polymers and biopolymers. Despite widespread application of MALDI, the fundamental processes of ion formation and desorption are still poorly understood. The chemistry of the MALDI process, occurring both during sample preparation and during ionization is reflected in the mass spectrum. As the MALDI technique now stands a low concentration of analyte molecules, which usually exhibit only moderate absorption per molecules, is embedded in matrix crystals consisting of a small, highly absorbing species. In this manner the efficient and controllable energy transfer is retained while the analyte molecules are separated from excessive energy that would lead to their decomposition. The matrix is believed to serve two major functions: adsorption of energy from the laser light and the isolation of analyte molecules from each other. There are 3 major methods for the preparation of samples for analysis which are quite quick and simple: dried droplet, surface and sandwich preparation. Experiments with pH indicator dyes serve as proof that analyte's charge state in the matrix crystals is the same as in solution. Upon laser desorption a sudden and explosive phase transition occurs and a dense plume of desorbed material is formed. The initial velocity of analyte ions in the plume depends only on the matrix used. Initial species formed as a result of laser desorption are tiny clusters. They consist of a matrix, analyte and other ionic species embedded in the matrix crystals all held together by hydrogen bonds and coulombic interactions. The first essential charging and thus ionization process is the statistical occurrence of clusters with a deficit/excess of anions of cations. Very small initial clusters are likely to be highly charged. Highly charged initial clusters cannot survive in the matrix plume and their charge drops. Clusters shrink by evaporation of neutral molecules. This paper presents only those cases leading to analyte ions and compares MALDI and the electrospray ionization technique.

Spectrometry, Mass, Matrix-Assisted Laser Desorpti↗
PubMed2005

Combined effect of heptaplatin and ionizing radiation on human squamous carcinoma cell lines.

Heptaplatin, cis-malonato [(4R,5R)-4,5-bis (amino-methyl)-2-isopropyl-1,3-dioxolane] platinum(II) (SKI-2053R, Sunpla) is a new platinum derivative with anti-tumor activity comparable to cisplatin on various cancer cell lines. Preclinical studies suggest that it is less nephrotoxic than cisplatin. This study was undertaken to examine the combined effect of heptaplatin and ionizing radiation on two established human squamous carcinoma cell lines (NCI-H520, SQ20B). The cytotoxic activity of heptaplatin was concentration-dependent in both cell lines. When low dose heptaplatin was combined with high dose ionizing radiation, there was an additive cytotoxic effect on NCI-H520 cells (P < 0.05), while a moderate dose of heptaplatin and a low dose of ionizing radiation had an additive cytotoxic effect on the growth of SQ20B cells (P < 0.05). FACS analysis and DAPI staining showed that their additive cytotoxic effects were correlated with the induction of apoptosis. Further studies are warranted using heptaplatin and ionizing radiation in squamous cell carcinoma as a substitute for cisplatin.

Antineoplastic Agents↗
PubMed2004

[Combined effects of endostatin gene transfer and ionizing radiation on lung adenocarcinoma model of A549-cells].

OBJECTIVE: The combined inhibition effects of endostatin gene transfer and ionizing radiation on lung adenocarcinoma model of A549-cell were investigated. METHODS: Human endostatin gene was transferred into lung adenocarcinoma A549 cell by retrovirus-mediation to obtain an A549/Endo cell. A549 and A549/Endo cells were xenoimplanted in nude mice respectively (each group included 10 mice). Then, the changes of the tumor size of each group (n = 5) and its growth inhibition rate were estimated. The implanted tumors of each group (n = 5) were exposed to radiation with 20 Gy at 28 day after implantation. They were irradiated again with 20 Gy 3 day later. The ionizing radiation was strictly confined to the tumor by shielding the rest of the body with lead. The size of tumor was measured periodically. The microvessel density (MVD) of 4 groups of implanted tumors (A549, A549/Endo, A549 + IR and A549/Endo + IR) were compared on day 42 postgrafting by the immunohistochemical method. RESULTS: PCR confirmed that endostatin gene was inserted into the genomic DNA of human lung adenocarcinoma A549 cell. The tumor formation time showed significant difference (P < 0.05) between group A549 (7.8 +/- 1.6) d and group A549/Endo (12.2 +/- 1.7) d. At the time of day 42 postgrafting, the tumor sizes of group A549 and group A549/Endo were (927.8 +/- 269.2) mm3 and (217.5 +/- 81.5) mm3 respectively (P < 0.01), and the tumor growth inhibition rate was 76. 5%. At the time of day 14 after irradiation, the tumor sizes of group A549 and group A549/Endo were (157.7 +/- 49.0) mm3 and (4.6 +/- 2.9) mm3 respectively (P < 0.01). The results of immunohistochemical detection showed that the MVD of-A549/Endo implanted tumor was significantly decreased [21.62 +/- 3.55 compared with A549 implanted tumor 35.78 +/- 5.67 (P < 0.01)]. Moreover , it also showed that ionizing radiation could further reduce the MVD of A549/Endo implanted tumor from 21.62 +/- 3.55 to 11.32 +/- 2.78 (P < 0.01). CONCLUSIONS: Retroviruses can highly mediate the transfer of endostatin gene into the adenocarcinoma cells. Endostatin gene transfer can inhibit the xenoimplanted tumor growth by its direct inhibition on neovascularization. The combination of endostatin gene transfer with ionizing radiation treatment can synergistically inhibit the neovascularization and the growth of lung adenocarcinoma.

Adenocarcinoma↗
PubMed2005

[Mitogenic and mutagenic effects of ionized air on Allium fistulosum L].

In the apical meristem of Allium fistulosum, the relationship between peroxide lipid oxidation, antioxidant activity, proliferative processes, the yield of chromosomal aberrations and duration the exposure to ionized air was studied. Under the influence of air oxygen ions, superoxide dismutase and catalase activities increased, proliferative processes were stimulated, and shifts occurred in the process of lipid peroxidation in cells of A. fistulosum. When these cells were treated with air oxygen for 40 min, hydrogen peroxide and iron sulfate (II) enhanced oxygen biostimulating effect via stimulation of antioxidant enzyme activity and inhibition of lipid peroxidation. Under these conditions, cell proliferation was intensified and the yield of chromosomal aberrations was reduced in A. fistulosum rootlets. When the time of seed treatment with ionized air was increased to 80 min, lipid peroxidation was activated, antioxidant enzyme activity was inhibited, and the yield of chromosomal aberration increased in seedlings. It was concluded that the biostimulating activity of ionized air was mediated by active oxygen species generated in the cell. The accumulation of TBA(thiobarbituric acid)-reactive products was shown to be related to a decrease in antioxidant enzyme activity and an increase in the yield of chromosomal aberrations. It is emphasized that the mutagenic effect of ionized air is associated with generating conditions that support Fenton reaction and OH-radical formation in the cell.

Air Ionization↗
PubMed2006

Increased cell compaction can augment the resistance of HT-29 human colon adenocarcinoma spheroids to ionizing radiation.

One of the most important questions in tumor biology is the understanding of the mechanisms responsible for the resistance of cancer cells to radiotherapy. In the present study, the possible role played by cell-cell interactions in determining the response of tumor cells to ionizing radiation was investigated. HT-29 colon adenocarcinoma spheroids were irradiated with a dose of 15 Gy in two different stages of growth characterized by diverse degrees of compaction: loosely organized spheroids (early spheroids) and compacted spheroids (late spheroids). Morphological analyses demonstrated that late spheroids were less damaged than early spheroids. Moreover, analyses of the cell cycle and cell death showed that ionizing radiation induced necrosis in early spheroids and apoptosis in late ones. From these results it can be concluded that late, compacted spheroids are more resistant to ionizing radiation than early, loose spheroids. In order to understand the mechanisms regulating this compaction-induced resistance of late spheroids, E-cadherin/beta-catenin complex expression and distribution were analyzed. In late spheroids, E-cadherin/beta-catenin complexes were shown to be tethered to the cytoskeleton, and since this organization has been demonstrated to strengthen cell-cell adhesion in other systems, it can be postulated that the same is true in HT-29 spheroids. In conclusion, it can be hypothesized that compaction of HT-29 spheroids is mediated by the reorganization of E-cadherin/beta-catenin complexes on the plasma membrane and that this compaction may be responsible for the increase in resistance of HT-29 spheroids to ionizing radiation.

Adenocarcinoma↗
PubMed2006

[Transgenerational effects of parental exposure to ionizing radiation].

The deleterious effects of exposure to ionizing radiation on human health have been known for many years. The main long term effect of this exposure is an increase in the risk for developing benign and malignant tumors in the exposed population. This review summarizes the existing data on the possible effects of ionizing radiation on the second generation, focusing on cancer risk. The two mechanisms through which parents' exposure to radiation could affect their children's health are intrauterine exposure of the fetus and preconception exposure of the gonads. Intrauterine exposure to ionizing radiation has teratogenic and carcinogenic effects. Most case-control studies have shown a 40-50% increase in the risk of cancer following intrauterine exposure to medical diagnostic radiation at doses of 10-20mGy. Results of these studies have greatly contributed to the strict radiation protection guidelines at pregnancy existing today. Although animal studies have shown that gonadal exposure to high doses can cause heritable genetic changes, this effect has not been demonstrated unequivocally in epidemiological studies. A case-control study suggested an association between preconception irradiation and leukemia/non-Hodgkin's lymphoma in children of male workers at a nuclear plant in the UK (the Gardner hypothesis). This report generated substantial interest and research; however, subsequent occupational studies failed to confirm the association. Negative results were also reported in studies of the atomic bomb survivors and survivors of childhood cancer. In summary, epidemiological studies do not support the association between gonadal exposure to ionizing radiation and the development of cancer and other genetic diseases among offspring.

Adult↗
PubMed1983

[Effect of artificial air ionization on broilers].

Tested was the artificial ionization of the air in climatic chambers in attempts to maintain the abiotic ecologic factors within the parameters required by the industrial technology of raising. The feeding and raising of birds were carried in accordance with the provisions of the Bulgarian State Standard requirements. The experiments were carried out with day-old chick broilers divided into two equated groups. All parameters of the production milieu in which the groups were kept were unified with the exception of the ionization of air. The latter was effected following the pattern of a special programme worked out by the authors' team, providing for various exposures and concentrations of the ions in dependence on the age of birds. The investigation of the abiotic and biotic factors acting in the two chambers has revealed a reliable drop of the microbial contamination of the air under the effect of artificial ionization. It has been found that air ionization applied according to the tested programme stimulates the life processes in the body of broilers as evidenced by the anabolic processes with proteins, the higher vitamin A and E level in the liver, and the activation of haemopoiesis. As the result of the reduced microbial contamination of the air and the biologic action of the air ions on the body of the birds in the test group higher weight was obtained (by 19 g) as against the controls at a lower feed intake per unit of gain, with higher indices of the poultry meat. The chemical investigation of such meat of the test group birds has revealed higher protein and essential amino acid content.

Air Ionization↗