High radiopathogenic children's loads caused by "low doses" of technogenic chronic radiation

To study influence of "low radiodoses" on their early effects, the method to monitor peculiarities for human biochemphysic pathologies caused by technogenic chronic doses divided by natural constant radiation background doses (relative radiation loads as their ratios, RRL) has been developed. High radiolabile coupled system of harmful catabolites of the initiated lipoperoxic cascade with essential radioprotectors (vitamins A and E as natural antioxidants) as pathogenic significant test-objects were monitored. For exposed children low radiation technogenic doses were high enough as RRL to disturb and to dysregulate both systems. For evaluation of individual radiosensitivity significances of age for children especially, as of the biochemical status for both systems are shown. The approach permits to investigate pathologies of studied systems as primary factors for mechanisms of related radiogenic known somatic health secondary consequences and to use it for some important practical applications.     

Beneficial effects of enrichment of chicken meat with n-3 polyunsaturated fatty acids,vitamin E and selenium on health parameters: a study on male rats

Consumption of chicken meat enriched with bioactive compounds such as n-3 polyunsaturated fatty acids (PUFAn-3), vitamin E (vE) and selenium (Se) can help prevent many diseases and can be used to deliver those substances to humans. This might be of importance as chicken meat consumption is increasing worldwide. The effects of enriching chicken meat with PUFAn-3, vE and Se through dietary interventions were studied in rats. Four groups of Ross 308 female broilers from day 22 to day 35 of age were fed control diet (L) that contained lard and 80 mg vE and 0.3 mg Se/kg, or diets that contained rape seeds and fish oil with the same level of Se and vE as in the control diet, the same level of Se as in the control and 150 mg vE/kg, or 150 mg of vE and 0.7 mg Se/kg. Broiler carcasses were boiled, deboned, lyophilized and pooled by group. Boiled edible components of chicken carcass (BECC) were included (240 g/kg) in the diets fed to four groups of ten 10-week-old Wistar male rats for 8 weeks. Inclusion of BECCs modulated dietary fatty acid profile in the rat diets. Feeding these diets did not influence parameters related to growth or relative weights of internal organs in the rats. Feeding BECCs with lower PUFAn-6/n-3 decreased the n-6/n-3 ratio in the rat brain and liver, and increased the proportion of docosahexaenoic acid in the brain lipids. Liver cholesterol level was similar among the experimental groups, whereas the concentration of vE in the liver of rats fed BECC with increased vE levels was higher than that in the rats fed BECC with the basal vE level. Haematological and biochemical parameters in blood were within the normal range for rats, but a few rats showed a tendency towards increased levels because of the higher vE and Se level. The health-promoting effect of feeding rats PUFAn-3 enriched BECC was more pronounced when an increased dietary level of vE was used, but the increased level of Se did not provide the rats with additional benefits. Thus, the findings indicate that BECC enriched with PUFAn-3 and vE by a dietary intervention is a functional food with great potential of implementation.     

Analysis of carotid artery deformation in different head and neck positions for maxillofacial catheter navigation in advanced oral cancer treatment

ABSTRACT: BACKGROUND: To improve the accuracy of catheter navigation, it is important to develop a method to predict shifts of carotid artery (CA) bifurcations caused by intraoperative deformation. An important factor affecting the accuracy of electromagnetic maxillofacial catheter navigation systems is CA deformations. We aimed to assess CA deformation in different head and neck positions. METHODS: Using two sets of computed tomography angiography (CTA) images of six patients, displacements of the skull (maxillofacial segments), C1--C4 cervical vertebrae, mandible (mandibular segment), and CA along with its branches were analyzed. Segmented rigid bones around CA were considered the main causes of CA deformation. After superimposition of maxillofacial segments, C1--C4 and mandible segments were superimposed separately for displacement measurements. Five bifurcation points (vA--vE) were assessed after extracting the CA centerline. A new standardized coordinate system, regardless of patient-specific scanning positions, was employed. It was created using the principal axes of inertia of the maxillofacial bone segments of patients. Position and orientation parameters were transferred to this coordinate system. CA deformation in different head and neck positions was assessed. RESULTS: Absolute shifts in the center of gravity in the bone models for different segments were C1, 1.02 +/- 0.9; C2, 2.18 +/- 1.81; C3, 4.25 +/- 3.85; C4, 5.90 +/- 5.14; and mandible, 1.75 +/- 2.76 mm. Shifts of CA bifurcations were vA, 5.52 +/- 4.12; vB, 4.02 +/- 3.27; vC, 4.39 +/- 2.42; vD, 4.48 +/- 1.88; and vE, 2.47 +/- 1.32. Displacements, position changes, and orientation changes of C1--C4 segments as well as the displacements of all CA bifurcation points were similar in individual patients. CONCLUSIONS: CA deformation was objectively proven as an important factor contributing to errors in maxillofacial navigation. Our study results suggest that small movements of the bones around CA can result in small CA deformations. Although patients' faces were not fixed properly during CT scanning, C1--C4 and vA--vE displacements were similar in individual patients. We proposed a novel method for accumulation of the displacement data, and this study indicated the importance of surrounding bone displacements in predicting CA bifurcation.     

Increased vitamin E content in the lung after ozone exposure: a possible mobilization in response to oxidative stress

Vitamin E (vE) is a biological free radical scavenger capable of providing antioxidant protection depending upon its tissue content. In previous studies, we observed that vE increased significantly in rat lungs after oxidant exposure, and we postulated that vE may be mobilized to the lung from other body sites under oxidative stress. To test this hypothesis, we fed Long-Evans rats either a vE-supplemented or a vE-deficient diet, injected them intraperitoneally with 14C-labeled vE, and then exposed half of each group to 0.5 ppm ozone (O3) for 5 days. After exposure, we determined vE content and label retention in lungs, liver, kidney, heart, brain, plasma, and white adipose tissue. Tissue vE content of all tissues generally reflected the dietary level, but labeled vE retention in all tissues was inversely related to tissue content, possibly reflecting a saturation of existing vE receptor sites in supplemented rats. Following O3 exposure, lung vE content increased significantly in supplemented rats and decreased in deficient rats, but the decrease was not statistically significant, and vE content remained unchanged in all other tissues of both dietary groups. Retention of 14C-labeled vE increased in all tissues of O3-exposed rats of both dietary groups, except in vE-deficient adipose tissue and vE-supplemented brain, where it decreased, and plasma, where it did not change. The marked increases in lung vE content and labeled vE retention of O3-exposed vE-supplemented rats support our hypothesis that vE may be mobilized to the lung in response to oxidative stress, providing that the vitamin is sufficiently available in other body sites.     

Clinical immunological disorders in children from various observation cohorts exposed to radiation factor during various stages of oncogenesis

The immune status disorders and features depending on the radiation impact type in various cohorts of radiation observations long after the Chernobyl (CNPP) disaster and the possible role of these disorders in development of chronic somatic pathology in children are shown. Lymphocyte depletion, T-cell immunity component disorders in the form of cell contraction with CD3, CD4, CD8 markers and the B-cell immunity component disorders in the form of reducing the quantity of CD10, CD23 marker cells were observed in children subject to combined chronic irradiation by 131I, 137Cs, 90Sr radionuclides. The descendants of irradiated parents (the 1st generation; children of the Chernobyl accident consequences liquidators, children of the citizens of radiation contaminated territories with various 137Cs levels) had immunity disorders of different type. A change in the total amount of NK-cells (CD16(+)-lymphocytes) is the general sign for all radiation risk groups; however, people subject to direct radiation impact demonstrated reduction of the antitumor protection potency, whereas descendants of irradiated ones demonstrated its activation with typically increasing number of CD16(+)-lymphocytes. In all radiation risk groups, a tendency to reduction of a number of cells involved in the leukocytal activation with the "pluripotential activation" marker (CD38 marker cells), proliferating cells (CD71 marker cells) and the increase of relative amount of cells with apoptosis marker (CD95(+)-lymphocytes). Immune disorder markers under the radiation impact in various cohorts of children's observation are suggested: antigens: CD4, CD8, CD10, CD23, CD16, CD38, CB71, CD95.     

The retrospective cytogenetic dosimetry using the results of conventional chromosomal analysis in Chernobyl clean-up workers

The paper presents the results of the cohortal biodosimetry carried out in 435 Chernobyl clean-up workers, who were surveyed with the conventional cytogenetic technique in terms from several days to 10 years after the end of their duties in the Chernobyl accident exclusive zone. An empirical model of the aberrant cell dynamics was utilized for the calculation of mean initial yields of dicentrics and centric rings in groups with different terms and duration of staying in the Chernobyl zone. Corresponding protracted irradiation doses estimated from aberration levels ranged from 79 to 670 mGy. The probabilistic distribution of the radiation doses was constructed by the applying the Bayesian analysis to initial individual chromosome exchange yields extrapolated to the exposure termination moment. This distribution was characterized by the mean dose about 460 mGy and maximum of probability density in the interval of 50-300 mGy. For the late somatic risk assessment in clean-up workers the probabilistic distribution of equivalentally-acute radiation doses was proposed; that had the mean value about 270 mGy, modal classes of 250-350 mGy and 99.8% of the probability density concentrated within the dose range from 0 to 1000 mGy.     

不同人工饲料对刀鲚幼鱼生长、血清生化指标及脂质代谢酶活性的影响

试验选择体长、体质量基本一致的6月龄刀鲚,分别投喂日粮1(人工配合软颗粒饲料)、日粮2(人工配合饲料与鱼油混合的软颗粒饲料)及日粮3(人工配合缓沉硬颗粒料)3种配合饲料60 d,探讨不同人工饲料对刀鲚幼鱼生长性能、血清生化指标及脂质代谢酶活性的影响.结果表明: 日粮2组和日粮3组的幼鱼体质量、体质量增长率、特定生长率和肥满度显著高于日粮1组;日粮3组的饵料系数显著低于日粮1组和日粮2组;各组间体长、体长/体高、体长/体厚、肝体比及脏体比等生长指标及总蛋白、白蛋白、血糖、胆固醇和甘油三酯等血清生化指标均无显著差异;日粮1组的肉碱软脂酰基转移酶-Ⅰ(CPT-Ⅰ)含量显著高于日粮2组和日粮3组;日粮2组的肉碱软脂酰基转移酶-Ⅱ(CPT-Ⅱ)含量显著低于日粮1组和日粮3组;各组间淀粉酶、胃蛋白酶、脂肪酶活性及脂蛋白脂酶(LPL)和乙酰辅酶A羧化酶(ACC)含量均值无显著差异.表明日粮中添加多不饱和脂肪酸有利于刀鲚幼鱼的生长,缓沉饲料的利用效率最高,适合于刀鲚幼鱼驯养阶段使用.     

The Roles of Melatonin and Vitamin E Plus Selenium in Prevention of Oxidative Stress Induced by Naloxone-Precipitated Withdrawal in Heroin-Addicted Rats

The therapeutic effects of melatonin or vitamin E plus Se (vE + Se) on the restrain of the heroin withdrawal-induced oxidative stress were studied. For this, rats were divided into ten groups. The rats were injected by fixed or variable doses of heroin for 16 consecutive days, and naloxone was given 1 h after the last heroin injection. One hour after naloxone administration, some groups were treated with melatonin or vE + Se. After 1 h this, blood samples were taken, and the levels of malondialdehyde (MDA) and reduced glutathione (GSH) in whole blood, ascorbic acid, α-tocopherol, retinol, β-carotene, nitrite, nitrate, and ceruloplasmin levels in the serum were measured. Our findings showed that, naloxone administration precipitated the heroin withdrawal. This also increased the level of MDA and decreased the levels of GSH in blood. Melatonin or vE + Se administration prevented the rise in MDA levels and increased the GSH levels. On the other hand, there were some significant differences between α-tocopherol, retinol, β-carotene, nitrite, nitrate, and ceruloplasmin levels of experimental groups. Results of present study showed that heroin withdrawal increased the lipid peroxidation and depressed endogenous antioxidative systems. Additionally, melatonin or vE + Se administrations prevented lipid peroxidation and augmented endogenous antioxidant defense systems.     

The role of cytogenetic examination for prognosis of remote consequences of irradiation

Correlation between the level of somatic pathology and cytogenetic characteristics of blood was analyzed in a group of liquidators of the accident at the Chernobyl Nuclear Power Plant (ChNPP). A statistically significant correlation was found between the occurrence of cardiovascular diseases and the level of chromosome aberrations (total frequency of chromosome aberrations, frequency of dicentrics and centric rings, frequency of chromatid aberrations). The results obtained are of great importance for the substantiated prediction of the development of postradiation pathologies.     

Normative data for total and free acid-labile subunit of the human insulin-like growth factor-binding protein complex in pre- and full-term newborns and healthy boys and girls throughout postnatal development

Insulin-like growth factors (IGFs) circulate in plasma as part of a 150-kD complex that also contains IGF-binding protein-3 (IGFBP-3), a protein that binds IGF-I and IGF-II with high affinity, and an acid-labile subunit (ALS) that does not directly bind IGFs. Because the ALS assay methods currently being used are relatively new, there is a need for updated normative reference data. We report the normative data in 17 preterm infants (10 males and 7 females), 30 normal full-term newborns (15 males and 15 females) and 150 normal children who where divided into 5 groups according to their Tanner stage (15 males and 15 females per group). Serum levels of total and free ALS were significantly lower in premature infants than in full-term newborns, but all newborns had significantly lower levels than Tanner stage-I children (p<0.001, ANOVA). A significant increase was seen between Tanner stages I-III in both sexes (p<0.001, ANOVA). No differences were found between sexes at any developmental age studied. Significant correlations (p<0.001) were seen between total and free ALS concentrations and IGF-I (r = 0.50 and 0.60, respectively), free IGF-I (r = 0.37 and 0.36), IGF-II (r = 0.37 and 0.27), IGFBP-1 (r = -0.48 and -0.49), IGFBP-2 (r = -0.44 and -0.51) and IGFBP-3 (r = 0.67 and 0.59) at all Tanner stages. However, no correlation was found with IGFBP-1, -2 or -3 levels at birth. This study shows normal values in a population of preterm infants and healthy Spanish newborns and subjects of both sexes at all stages of pubertal development and indicate the different relationships between the components of the IGF system during intra- and extrauterine life.     

Risk of acute childhood leukaemia in Sweden after the Chernobyl reactor accident. Swedish Child Leukaemia Group.

OBJECTIVE--To evaluate the risk of acute childhood leukaemia in areas of Sweden contaminated after the Chernobyl reactor accident in April 1986. DESIGN--Population based study of childhood leukaemia diagnosed during 1980-92. SETTING--Coordinates for places of residence of all 1.6 million children aged 0-15 years; aerial mapped areas of Sweden heavily contaminated after the Chernobyl accident. SUBJECTS--888 children aged 0-15 years with acute leukaemia diagnosed in Sweden during 1980-92, identified with place of birth and residence at diagnosis. MAIN OUTCOME MEASURES--Risk of leukaemia in areas contaminated after the Chernobyl accident compared with the rest of Sweden and in the same areas before the accident. RESULTS--During six and a half years of follow up after the accident the odds ratio for acute leukaemia was 0.9 (95% confidence interval 0.6 to 1.4) in highly contaminated areas (> or = 10 kBq/m2) compared with the same areas before the accident. For the subgroup acute lymphoblastic leukaemia in children aged under 5 years at diagnosis the odds ratio was 1.5 (0.8 to 2.6). For all cases diagnosed after May 1986 in highly contaminated areas compared with areas of low contamination the odds ratio was 0.9 (0.7 to 1.3). For acute lymphoblastic leukaemia in children aged under 5 years at diagnosis the odds ratio was 1.2 (0.8 to 1.9) in highly contaminated areas compared with areas of low contamination. Dose-response analysis showed no correlation between the degree of contamination and the incidence of childhood leukaemia. CONCLUSION--There has been no significant increase in the incidence of acute childhood leukaemia in areas of Sweden contaminated after the Chernobyl reactor accident.     

Role of non-radiation factors in forming cytogenetic effects in evacuees from a 30-km zone of the Chernobyl Nuclear Power Plant

The time-effect relationship for chromatid type aberrations, chromosome type fragments, hyperploidy and polyploidy levels in peripheral blood lymphocytes were investigated in inhabitants of t. Pripiat' and nearby villages, who were departured from the Chernobyl NPP 30-km exclusive zone during first days after the Chernobyl catastrophe. The time-course changes of the mentioned cytogenetic indices in evacuees were displayed as a gradual decline of chromosomal rearrangements and genome abnormality frequencies from the statistically elevated level in the first 1-2 years after the accident to the subcontrol meanings at the end of the 14-years observation period. In early terms after exposure the frequency of chromatid exchanges in adult men and the polyploidy level in women aged 23-35 years were sufficiently increased comparing with other evacuee subgroups. Some peculiarities of the fragment aberration frequency dynamics were shown for persons with different terms of the departure from the Chernobyl zone. The role of the combination of mutagenic factors acted in the accidental situation at Chernobyl for inducing the elevated level of cytogenetic damage in evacuees is discussed.     

Time-effect relationship for unstable chromosome exchange levels in Chernobyl clean-up workers

The post-irradiation changes of dicentric and centric ring levels were studied in Chernobyl liquidators using the data of 507 individual chromosomal surveys of persons sampled at different time after their activities at Chernobyl NPP accident zone. The time-effect relationship within 0-10.5 years after exposure was displayed as exponential decline of the mean chromosome exchange frequency with average decay half-time 2.2 y. During 10.5-13 years after exposure the increasing and stabilization of chromosome exchange yield on the level 2-3-times higher than control was observed. In the first few months after irradiation the dicentric and centric ring frequency in liquidators had the clear reverse correlation with the duration of person's duties at the Chernobyl zone. The parameters of unstable chromosome exchange elimination were independent on the initially induced aberration yield, that resulted in earlier reaching the subcontrol level in persons who had more protracted duration of duties at the Chernobyl accident zone.     

Hereditary minisatellite mutations among the offspring of Estonian Chernobyl cleanup workers

A single accidental event such as the fallout released from the Chernobyl reactor in 1986 can expose millions of people to non-natural environmental radiation. Ionizing radiation increases the frequency of germline mutations in experimental studies, but the genetic effects of radiation in humans remain largely undefined. To evaluate the hereditary effects of low radiation doses, we compared the minisatellite mutation rates of 155 children born to Estonian Chernobyl cleanup workers after the accident with those of their siblings born prior to it. All together, 94 de novo paternal minisatellite mutations were found at eight tested loci (52 and 42 mutants among children born after and before the accident, respectively). The minisatellite mutation rate was nonsignificantly increased among children born after the accident (0.042 compared to 0.036, OR 1.33, 95% CI 0.80-2.20). Furthermore, there was some indication of an increased mutation rate among offspring born after the accident to workers who had received doses of 20 cSv or above compared with their siblings born before the accident (OR 3.0, 95% CI 0.97-9.30). The mutation rate was not associated with the father's age (OR 1.04, 95% CI 0.94-1.15) or the sex of the child (OR 0.95, 95% CI 0.50-1.79). Our results are consistent with both no effect of radiation on minisatellite mutations and a slight increase at dose levels exceeding 20 cSv.     

Vaccinia virus A6L encodes a virion core protein required for formation of mature virion

Vaccinia virus A6L is a previously uncharacterized gene that is conserved in all sequenced vertebrate poxviruses. Here, we constructed a recombinant vaccinia virus encoding A6 with an epitope tag and showed that A6 was expressed in infected cells after viral DNA replication and packaged in the core of the mature virion. Furthermore, we showed that A6 was essential for vaccinia virus replication by performing clustered charge-to-alanine mutagenesis on A6, which resulted in two vaccinia virus mutants (vA6L-mut1 and vA6L-mut2) that displayed a temperature-sensitive phenotype. At 31 degrees C, both mutants replicated efficiently; however, at 40 degrees C, vA6L-mut1 grew to a low titer, while vA6L-mut2 failed to replicate. The A6 protein expressed by vA6L-mut2 exhibited temperature-dependent instability. At the nonpermissive temperature, vA6L-mut2 was normal at viral gene expression and viral factory formation, but it was defective for proteolytic processing of the precursors of several major virion proteins, a defect that is characteristic of a block in virion morphogenesis. Electron microscopy further showed that the morphogenesis of vA6L-mut2 was arrested before the formation of immature virion with nucleoid and mature virion. Taken together, our data show that A6 is a virion core protein that plays an essential role in virion morphogenesis.     

Analysis of blood lymphocyte subsets in children living around Chernobyl exposed long-term to low doses of cesium-137 and various doses of iodine-131

Epidemiological studies have found that children living around Chernobyl have rates of respiratory tract illness that are higher than those seen in the area before the Chernobyl accident. The present study investigates the possible effects of radiation exposure on the composition of peripheral blood lymphocyte subsets in children living around Chernobyl. Two hundred nineteen healthy children and children suffering from recurrent respiratory diseases aged 6-14 years who received both low doses of radiation to the whole body from (137)Cs and various doses of radiation to the thyroid from (131)I as fallout from the accident were assessed 5 (1991) and 8-10 years (1994-1996) after the accident. A total of 148 healthy children and children suffering from recurrent respiratory diseases living in noncontaminated areas were also evaluated as controls. Children with recurrent respiratory diseases who lived around Chernobyl had a significantly lower percentage of T cells and a higher percentage of NK cells compared to control children with recurrent respiratory diseases during the study period. In contrast to the findings in 1991, a significant decrease in the percentage of helper-inducer cells was observed in children with recurrent respiratory diseases in 1994-1996. In contrast to 1991, there is a positive correlation between the percentage of helper-inducer cells, the helper-inducer/cytotoxic-suppressor cell ratio, and the dose of radiation to the thyroid of healthy children from (131)I in 1994-1996. There was a positive correlation between the dose of radiation to the thyroid from (131)I and the percentage of helper-inducer cells in children with recurrent respiratory diseases 5 years (1991) after the accident. Further, the dose of radiation to the thyroid from (131)I correlated negatively with the percentage of T and B cells and positively with the percentage of NK cells in children with recurrent respiratory diseases 8-10 years (1994-1996) after the accident. These results raise the possibility that long-term exposure to low doses of (137)Cs may have altered the composition of the T-cell subsets and NK cells in children with recurrent respiratory diseases. The differences in the composition of the peripheral blood lymphocyte subsets between healthy children and those with recurrent respiratory diseases may be attributed to long-term low-dose exposure of the whole body to radiation from (137)Cs and exposure of the thyroid to radiation from (131)I subsequent to the Chernobyl accident.     

Level of chromosome aberrations in peripheral blood lymphocytes in evacuees from the 30-kilometer zone of the Chernobyl Atomic Energy Station and residents of radioactively-polluted territories in the long term after the Chernobyl accident

Eighteen Ukrainian evacuees from the Chernobyl exclusive zone, twenty one inhabitants of radioactively contaminated areas of Belarus and twelve control donors age-matched to the exposed persons were investigated 14-15 years after the Chernobyl accident for chromosomal aberration yields detected in blood lymphocytes by fluorescence in situ hybridisation technique. Unstable aberration yields measured in both Chernobyl cohorts were close to the background frequencies. Positive age-dependence trends in control donors were determined for the all type stable aberration levels. In evacuees the tendency for diminishing the difference between them and controls for stable aberration levels with persons' age increasing was found. The total stable chromosome exchange yields in evacuees 46-55 years old and inhabitants of areas with low contamination level didn't exceed the control values, but for younger evacuees and inhabitants of sufficiently contaminated regions the statistical increase above the age relevant background meanings was detected for this end-point. The advantages of using the FISH-detectable stable aberrations and particularly the total level of stable chromosome exchanges as the end-points for retrospective biological indication of past radiation exposure in Chernobyl cohorts were discussed.     

Quality and lipid composition of spermatozoa in rabbits fed DHA and vitamin E rich diets

The effects of fish oil (FO) and vitamin E (vE) dietary supplementation on semen quality, sperm susceptibility to lipid peroxidation, tocopherols content and fatty acid profiles were studied in rabbits. Fifty-two rabbit bucks randomly divided in four groups received a control diet and enriched diets containing either FO (1.5%, w/w), vE (200 mg/kg) or both. Semen volume, concentration, motility and viability were analysed at various time-points and the lipid composition was assessed on sperm cells. The phospholipid fatty acid profile was determined: n-6 PUFA were the major fatty acids found, with a proportion of 42%, whereas the n-3 PUFA accounted for nearly 1%, mainly represented by C22:6n-3 (docosahexaenoic acid, DHA). FO supplementation produced a seven-fold increase in the content of DHA in sperm phospholipids and a comprehensive rearrangement of the phospholipid fatty acid composition, while an unexpected negative effect of feeding high level of vE on the proportion of total PUFA was found. Despite the remarkable changes observed in sperm lipid composition, semen quality parameters were not affected by the dietary treatments and the interaction between the two dietary supplements had a significant effect only on sperm concentration. An increase in semen production by ageing and a concomitant rise in sperm susceptibility to in vitro peroxidation was found. α- and δ-tocopherol, present in rabbit sperm in similar amount, were not affected by dietary treatment. δ-tocopherol content had a significant linear negative regression with age and showed a significant negative correlation with the susceptibility to peroxidation values.     

Insulin-like growth factor-binding protein-2 levels in pediatric patients with growth hormone deficiency, eating disorders and acute lymphoblastic leukemia

Insulin-like growth factor (IGF)-binding protein-2 (IGFBP-2) is altered in different diseases and might be used as an indication of its severity. The aims of our study were to investigate: (1) the developmental pattern of the serum IGFBP-2 concentration at birth and during childhood and adolescence; (2) whether the serum IGFBP-2 level could be a marker for the diagnosis and evolution of diseases where the growth hormone (GH)-IGF axis is altered, and (3) whether this binding protein shows a relationship with IGF-I, its free fraction, IGFBP-1 and -3. We report reference values for 55 normal full-term newborns and 221 normal children who were divided into 5 groups according to their Tanner stage. Serum levels were higher in newborns when compared with Tanner stages I-V (p < 0.001, ANOVA), with no further changes throughout development. Furthermore, we studied IGFBP-2 levels in 24 children with congenital GH deficiency (GHD), 26 with acute lymphoblastic leukemia (ALL), 75 obese children, and 60 girls with anorexia nervosa (AN) at diagnosis and during a follow-up period. IGFBP-2 at diagnosis was increased in GHD, ALL and AN, and decreased in obesity (p < 0.05, ANOVA). During the follow-up, IGFBP-2 concentrations tended to normalize. IGFBP-2 correlated positively with IGFBP-1 and negatively with IGF-I and IGFBP-3 in normal subjects and at diagnosis of the pathologies studied. Although IGFBP-2 functions are not well understood, these results suggest a possible role for this protein in diseases where the GH-IGF axis is altered.     

Long-term follow-up cytogenetic survey and biological dosimetry in persons evacuated from 30-km Chernobyl NPP zone

The paper presents the results of the follow-up cytogenetic survey and biological dosimetry carried out in inhabitants of Pripiat' town and nearby villages, who were departured from the Chernobyl NPP 30-km exclusive zone during first days after the Chernobyl catastrophe. The unstable chromosome aberration level in inhabitants were significantly increased above control in terms up to 1 year after evacuation and declined gardually during next 14 years. In early period the cytogenetic damage frequency in evacuees showed no dependence on gender. The chromosome type aberration level appeared to be lower in young persons comparing with adults. The dicentrics plus centric rings yield had a positive correlation with duration of staying at Chernobyl zone. The average doses of protracted exposure were calculated from the dicentrics and centric rings yields; the dose estimations appeared to be 1.4 times higher in persons evacuated 3-11 days after the accident than that of in persons with shorter departure time. Uing the Bayesian analysis the probabilistic distribution of biological doses was constructed for the studied evacuees group. This distribution was characterized by a mean dose of 360 mGy, the modal doses of 200-450 mGy and 80% of probability density within the dose range 0-1000 mGy, that seems to be sufficient for considering the increased risk of late somatic radiation effects for this cohort.