Psychosocial effects of the Chernobyl nuclear disaster

The psychological factors surrounding the Chernobyl disaster include the sudden trauma of evacuation, long-term effects of being a refugee, disruption of social networks, illness, separation and its effects on families, children's perception and effects on their development and the threat of a long-term consequence with an endless future. Added to this was the breakdown of the Soviet Union with consequent collapse of health services, increasing poverty and malnutrition. These complexities made necessary new individual and social treatment methods developed in UNESCO Community Centres, within which some positives have resulted, such as the development of individual and group self help and the professions of counselling, social work and community development, practices which did not previously exist in the Soviet Union.     

Radiation effects in spheroids of cells exposed to alpha emitters

PURPOSE: To simulate spheroids of cells and use the spheroid models to establish methods of calculating cell survival following exposure to alpha irradiation from decays of 211At and 213Bi. METHODS: Using a Monte Carlo technique, two models of spheroids of cells were generated in which cells either did not or were allowed to overlap. At 40% packing of the volume it is shown that the two models are equivalent for longer-ranged alpha particles. The overlapping model was used to examine the effects of spheroid size and cell packing on cell survival. Cell survival was also calculated for different distributions of alpha decays such as uniform distribution within the spheroid, external to the spheroid and as a shell on the periphery of the spheroid. RESULTS: Three examples of the cell structure of the spheroids are shown. Detailed calculations show that cell survival decreases from 57% to 37% as the spheroid diameter increases from 75 microm to 225 microm for an average of one 211At decay per cell and 50% packing. Increasing the packing of the cells in the spheroid from 40% to 70% reduces survival from 46% to 26% for 200 microm diameter spheroids for one 211At or 213Bi decay per cell. The presence of small regions of unlabelled cells within the spheroids does not significantly change cell survival. CONCLUSIONS: Monte Carlo programmes generating spheroids of cells and their subsequent use to score cell survival for alpha irradiation should be useful in the design and interpretation of work on spheroids of cells in vitro and the application of such modelling to the study of very small tumours in vivo. Copies of the programmes are available from the author on request.     

Radiation effects in spheroids of cells exposed to alpha emitters

Purpose : To simulate spheroids of cells and use the spheroid models to establish methods of calculating cell survival following exposure to alpha irradiation from decays of 211 At and 213 Bi. Methods : Using a Monte Carlo technique, two models of spheroids of cells were generated in which cells either did not or were allowed to overlap. At 40% packing of the volume it is shown that the two models are equivalent for longer-ranged alpha particles. The overlapping model was used to examine the effects of spheroid size and cell packing on cell survival. Cell survival was also calculated for different distributions of alpha decays such as uniform distribution within the spheroid, external to the spheroid and as a shell on the periphery of the spheroid. Results : Three examples of the cell structure of the spheroids are shown. Detailed calculations show that cell survival decreases from 57% to 37% as the spheroid diameter increases from 75 μ m to 225 μ m for an average of one 211 At decay per cell and 50% packing. Increasing the packing of the cells in the spheroid from 40% to 70% reduces survival from 46% to 26% for 200 μ m diameter spheroids for one 211 At or 213 Bi decay per cell. The presence of small regions of unlabelled cells within the spheroids does not significantly change cell survival. Conclusions : Monte Carlo programmes generating spheroids of cells and their subsequent use to score cell survival for alpha irradiation should be useful in the design and interpretation of work on spheroids of cells in vitro and the application of such modelling to the study of very small tumours in vivo. Copies of the programmes are available from the author on request.     

Therapeutic effects of cooling swine skin exposed to sulfur mustard

Recent world events have highlighted the need for effective medical therapies for chemical weapon injuries. Of the chemical weapon agents, perhaps one of the most widely used, both historically and most recently in the Iran-Iraq War, is sulfur mustard (HD). No effective antidotes exist for this vesicant agent and, to this day, HD casualties are treated entirely symptomatically. Previous work carried out in this laboratory has indicated that cooling HD-exposed tissue may ameliorate the resultant injury. To further examine this, an anesthetized domestic swine model was used to investigate whether alteration of skin temperature had any effect either visually or histopathologically on the development and progression of HD-induced skin lesions over 7 days. Exposure of swine skin to HD vapor resulted in lesions whose severity was exposure time related (4, 8, 12, and 16 minutes). Postdecontamination heating of skin above ambient temperature (approximately 39 degrees C) resulted in worsening of the lesion, whereas postdecontamination cooling (approximately 15 degrees C) for between 2 to 4 hours postexposure lessened the severity of HD-induced injury. The authors conclude that the early, noninvasive and simplistic act of cooling HD-exposed skin may have a salutary effect on the severity of HD-induced cutaneous lesions.     

扶正解毒中药对高氡暴露大鼠防护作用的研究

目的 探讨扶正解毒中药对高氡暴露大鼠的防护作用。方法 18只SD大鼠按随机数字表法分为3组。将12只SD大鼠放入氡浓度为40 000 Bq/m³氡室环境中,随机分为氡暴露组和扶正解毒中药组,每组6只,每只大鼠暴露总时间为1890 h,即120工作水平月(WLM),剂量率为0.056 WLM/h;另取6只SD大鼠为对照组,在本底氡浓度小于50 Bq/m³的室温环境中喂养。以酶联免疫(ELISA)法检测各组大鼠血清肿瘤标志物癌胚抗原(CEA)、神经元特异性烯醇化酶(NSE)、细胞角蛋白19 片段(CYFRA21-1)浓度和p53抗体水平;以甲基化特异性PCR(MSP)法检测各组大鼠支气管肺灌洗液(BALF)细胞中p16基因的甲基化率。结果 氡暴露组大鼠血清CEA、NSE浓度分别为(396.62±148.74)和(9.09±0.90)μg/L,显著高于对照组的(12.35±4.43)、(1.47±0.15)μg/L(t=2.583、2.463, P<0.05);扶正解毒中药组CEA、NSE浓度分别为(70.89±44.71)和(4.31±1.37)μg/L,均显著低于氡暴露组,差异有统计学意义(t=2.921、2.526, P<0.05);氡暴露组大鼠血清CYFRA21-1水平和p53抗体浓度与对照组和防护剂组比较,差异无统计学意义(t=1.713、1.963, P>0.05);氡暴露组大鼠BALF细胞中出现p16基因甲基化,甲基化率为16.67%,而对照组和扶正解毒中药组没有出现p16基因甲基化。结论 扶正解毒中药能显著降低高氡暴露大鼠CEA、NSE水平和p16基因甲基化率,有较理想的氡辐射防护作用。     

小儿外伤性迟发性硬脑膜外血肿

目的 研究小儿外伤性迟发性硬脑膜外血肿的临床特点。并探讨其发生机制。方法 总结分析我科1991年1月-2001年10月收治的小儿外伤性迟发性硬脑膜外血肿23例。结果 本组手术清除血肿21例。血肿自行吸收2例。无死亡。结论 小儿迟发性外伤性硬脑膜外血肿多发生在伤后2-5d，占该类血肿78.3%，跌倒伤是主要的致伤原因，此类血肿可发生于颅内任何部位，但多伴有颅骨线形骨折。小儿外伤性迟发性硬脑膜外血肿及时发现和治疗，预后良好，CT扫描是可靠而简便的诊断方法，而延误诊断往往造成严重后果。     

小儿外伤性迟发性脑内血肿

目的 探讨小儿外伤性迟发性脑内血肿的临床特点，诊断和治疗。方法 回顾性分析我院1987年1月-1998年12月收治的27例小儿外伤性迟发性脑内血肿。结果 27例小儿外伤性迟发性脑内血肿中，行血肿清除术13例，颅骨钻孔血肿内置管 增强尿激酶外引流术6例，非手术治疗8例，26例治愈，1例死亡，死亡率3.70%。结论 进行性意识障碍，头痛，呕吐，贫血加重和生命体征不稳定是小儿迟发性脑内血肿的基本临床特征，高度警惕本病的发生，及时再次CF扫描有利于早期诊断，掌握好手术和非手术治疗的指征，是治愈本病的关键。     

Imaging evaluation of traumatic hematuria in children

The 3 major causes of traumatic hematuria in children are accidents, iatrogenic damage, and child abuse. While computerized tomography plays a major role in the evaluation of accidental trauma, ultrasound and routine radiography are important in the work-up of iatrogenic hematuria and injuries caused by child abuse. This paper reviews the role of these imaging modalities in diagnosing traumatic hematuria in children.     

Adaptive and cumulative effects in the dog exposed to routine +GZ acceleration

The development of adaptive and cumulative effects was investigated in 13 noninbred dogs regularly exposed to +GZ acceleration: Group I dogs were exposed 3 to 4 times a week for 2 months and Group 11 dogs were exposed 1 to 2 times a week for 5 months. The tolerance threshold was evaluated with respect to ECG abnormalities. The study of circulation reactions and acceleration tolerance threshold revealed the predominant development of adaptive changes that were more distinct in Group 11 dogs. Cumulative effects in the form of functional disorders of pulmonary vessels occurred in all experimental dogs but less frequently in Group II dogs. Morphological lesions of the lung tissue developed in Group I animals after 2 to 3 exposures and in Group II animals after 2 to 3 months, the incidence rate being lower in those latter. These findings suggest that adaptive and cumulative effects in response to regular exposures to threshold +GZ acceleration develop more or less in parallel.     

Imaging evaluation of traumatic hematuria in children

The 3 major causes of traumatic hematuria in children are accidents, iatrogenic damage, and child abuse. While computerized tomography plays a major role in the evaluation of accidental trauma, ultrasound and routine radiography are important in the work-up of iatrogenic hematuria and injuries caused by child abuse. This paper reviews the role of these imaging modalities in diagnosing traumatic hematuria in children.     

神经生长因子对噪声暴露下毛细胞的保护作用

目的观察神经生长因子（nervegrowthfactor,NGF）对噪声暴露下豚鼠耳蜗毛细胞的保护作用。方法健康杂色成年豚鼠20只,随机分成两组,每组10只。A组：强噪声暴露（非手术）组,B组：注射重组腺病毒（携带NGF基因并能表达NGF蛋白质）后,强噪声暴露。噪声暴露7d后,各组均行耳蜗石蜡切片、HE染色和耳蜗基底膜铺片,计数毛细胞。结果A组豚鼠耳蜗基底膜细胞不连续,毛细胞变形,部分毛细胞缺失,螺旋神经节发出的神经纤维与毛细胞的连接断裂;B组耳蜗结构没有明显变化,B组毛细胞数日明显高于A组（P〈0．01）。结论NGF对噪声暴露下的耳蜗毛细胞具有一定的保护作用。     

Inotropic and chronotropic effects of isoprenaline in rats exposed to 30 bar

Inotropic and chronotropic responses to the beta-agonist, isoprenaline (ISO) were studied with a transducer located in the left ventricle and a catheter placed in the left femoral artery in anesthetized rats at 1 and 30 bar. The hemodynamic control values were equal in both series. During ISO infusion the chronotropy increased equally (34%) at 1 and 30 bar. The inotropy increased by 38% during ISO infusion at 1 bar (Series 1). Increased inotropy (44%), and unchanged chronotropy were found during compression to 30 bar (Series 2). The ISO evoked inotropic responses in absolute values were greater at 30 bar than at 1 bar. Nevertheless, an equal relative (%) increase in inotropy was found during ISO infusion at 30 bar compared to 1 bar. The cardiac oxygen consumption was estimated to be 65% higher at 30 bar during ISO infusion compared to that at 1 bar.     

Percutaneous drainage of traumatic pancreatic pseudocysts in children

In the past, children with pancreatic pseudocysts have been managed surgically. We report seven children 3-13 years old with posttraumatic pancreatic pseudocysts who were managed with percutaneous catheter drainage. All procedures were performed with local anesthesia and intramuscular sedation under sonographic or CT guidance. Two of the pseudocysts were drained via a transgastric approach, the other five via direct transcutaneous access to the pseudocyst. The catheters were in place an average of 25 days (range, 8-66). There were no serious complications. Six patients became asymptomatic with return of the serum amylase to normal and resolution of the pseudocyst on follow-up sonograms. One patient, in whom the catheter became dislodged after 2 weeks, became asymptomatic, but he had a residual 2-cm pancreatic pseudocyst that resolved over the next 6 weeks. Our experience suggests that percutaneous drainage is a safe and effective method of treatment for traumatic pancreatic pseudocysts in children.     

Scintigraphic evaluation of traumatic splenic lesions in children

Ninety-eight children with recent blunt abdominal trauma which initially evoked clinical suspicion of splenic injury were examined with colloid scintigraphy of the spleen and the liver using multiple imaging views and with abdominal survey. Nineteen children were, in addition, examined with tomographic scintigraphy. The clinical findings and the course of the disorder were reanalyzed. Scintigraphy indicated splenic injury in 56 children and hepatic injury in another 5 children. The left lateral and the left oblique were the optimum imaging views for detecting splenic ruptures. Tomographic scintigraphy did not improve the diagnostic yield. Abdominal survey failed to indicate almost every second case of splenic rupture and provided no additional information of significance. The clinical review agreed with the scintigraphic diagnosis of splenic lesions but, in addition, it suggested possible splenic lesions in another 10 children with normal scintigraphy. This discrepancy cannot be explained as surgery was not employed; the occurrence of splenic lesions too small to become detectable at scintigraphy or to provoke clinically evident symptoms may be supposed.     

Cerebral MR imaging in uninfected children born to HIV-seropositive mothers and perinatally exposed to zidovudine

BACKGROUND AND PURPOSE: Mitochondrial dysfunction has been reported in HIV-negative children perinatally exposed to zidovudine, a drug often used in HIV-seropositive mothers during pregnancy. The purpose of this study was to determine the incidence of cerebral MR imaging findings in HIV-uninfected children exposed to zidovudine who present with unexplained neurologic symptoms. METHODS: Two expert groups conducted a systematic, retrospective review of all cerebral MR images available in a multicentric, nationwide French prospective cohort of children born to HIV-seropositive mothers to identify imaging abnormalities. Experts were blinded to each others' interpretations, to the children's neurologic symptoms, and to laboratory evidence of mitochondrial dysfunction. The incidence of abnormalities was determined and compared with the neurologic presentation and laboratory evidence of mitochondrial dysfunction. RESULTS: MR images from 49 HIV-uninfected children (mean age, 26 months) were available for study. All children were perinatally exposed to zidovudine. Twenty-two had probable or established mitochondrial dysfunction according to their symptoms and laboratory data. Twenty-seven children without mitochondrial dysfunction presented with unexplained neurologic symptoms (n = 14) or nonneurologic symptoms (n = 7), and six were asymptomatic. Sixteen of 22 MR images in children with mitochondriopathy were considered abnormal in both independent analyses. Diffuse hyperintensity in the supratentorial white matter (n = 9) and in the tegmentum pons (n = 9) were the most frequent anomalies. Imaging abnormalities were often multifocal (n = 10) and sometimes associated with necrotic areas (n = 3) and volume loss (n = 8). Although 19 of 27 MR images of children without mitochondrial dysfunction were mainly normal, abnormal images were observed in five of 14 children with unexplained neurologic symptoms and in three of six asymptomatic children. CONCLUSION: Images observed in children with antiretroviral-induced mitochondrial dysfunction are similar to those observed in congenital mitochondrial diseases. These images were also observed in symptomatic or asymptomatic children without evidence of systemic mitochondrial dysfunction.     

旋转磁场对小鼠骨髓型急性放射病治疗效果的研究

目的 研究旋转磁场对小鼠骨髓型急性放射病的治疗效果。方法 132只雄性BALB/c小鼠随机分为正常组(N),单纯磁疗组(M),单纯照射组(R)和照射磁疗组(R+M)4组,N组小鼠不作其他处理,R组和R+M组小鼠接受6.0 Gy剂量的 ⁶⁰Co γ 射线照射,M组及R+M组予以磁场处理30d,每天2次,每次1.5h。观察小鼠30d的存活率和存活期;分别于0、5、9、15、21、30d检测外周血细胞数;测定第9、23、30d骨髓单核细胞数(BMNC)、脾集落形成单位(CFU-S)、脾脏指数(脾体比)、骨髓细胞周期、细胞凋亡,观察股骨骨髓病理切片及检测骨形态发生蛋白(BMP2/4)的表达水平。结果 1N组和M组小鼠无死亡。R+M组与R组比较,磁疗提高了小鼠的存活率和存活期(P<0.01)。2R+M组与R组比较,磁疗提高了R+M组第15天外周血白细胞数及血红蛋白含量、第21天红细胞数、第30天血小板数(P<0.05)。3第9天R+M组CFU-S、BMNC数、细胞G₂+M期比例高于R组,而总凋亡率低于R组(P<0.05)。第23天脾脏指数R+M组高于R组(P<0.05)。4骨髓病理检查显示,磁场可促进照射后骨髓造血组织结构的修复,R组骨髓早期较空虚,而R+M组骨髓细胞较充盈,随着时间的推移,两者均逐渐恢复正常;R+M组的骨髓BMP2/4表达水平亦明显高于R组。结论 旋转磁场对放射损伤小鼠骨髓造血具有明显的保护作用,能减少骨髓细胞的凋亡,其机制可能是促进放射损伤后造血细胞和造血微环境的修复。     

Onset of behavioral effects in mice exposed to 10 Gy 60Co radiation

The effects of 10 Gray (Gy) 60 Co radiation on social behavior, locomotor activity, and body weight were assessed in individually housed male Swiss-Webster mice. In Experiment 1, aggressive behavior was evaluated prior to irradiation and for 7 d postirradiation by placing an untreated intruder in the irradiated or sham-irradiated resident's home cage for 5 min. Offensive aggressive behavior was not affected significantly by radiation until day 7 postirradiation, when attack latency increased, the frequency and duration of fighting decreased, and the frequency of bites, lunges, and chases decreased. Untreated intruder mice paired with irradiated resident mice showed a decrease in the duration of defensive upright postures and a decrease in the frequency of defensive upright postures, squeaks, and escapes on day 7 postirradiation. In Experiment 2, locomotor activity and body weight were monitored for 7 d postirradiation. Body weight was decreased in irradiated mice beginning 4 d postirradiation. Locomotor activity was suppressed in irradiated animals 90 min after irradiation and remained depressed throughout the 7-d testing period.