Co-transfer of parthenogenotes and single porcine embryos leads to full-term development of the embryos.

It has long been known that several embryos are needed to establish and maintain pregnancy during early gestation in pigs. In this study, we assessed whether co-transfer of parthenogenotes with a single embryo was sufficient to maintain development of the embryo. Embryos were recovered at morula and early blastocyst stages from gilts that had been artificially inseminated. Parthenogenotes were produced from oocytes matured in vitro, activated by electrical stimulation, and then cultured for 110h. Those that had developed to morula- or blastocyst-like stages at 110h post-activation were transferred to recipient pigs either with or without morula or blastocyst stage embryos. Parthenogenotes that were transferred to recipients in the absence of embryos were viable up to 30 days post-activation and formed limb-buds; at 40 days, however, all were dead or degenerate. Among pigs that received both parthenogenotes and a single embryo, seven of nine (77.8%) delivered a normal piglet at full-term. This study therefore demonstrates that parthenogenotes can be used in place of embryos to establish pregnancy and promote development of a single co-transferred embryo. This method may be applied to rescue high value porcine embryos that are difficult to produce, such as transgenic cloned embryos, or for embryos frozen as a genetic resource.

Selective accumulation of ALA-induced PpIX and photodynamic effect in chemically induced hepatocellular carcinoma.

The possibility of 5-aminolaevulinic acid-based photodynamic therapy (ALA-PDT) for liver cancer was investigated using a chemically induced hepatocellular carcinoma (HCC) model. Endogenously synthesised protoporphyrin IX (PpIX) following the administration of ALA is an effective photosensitiser for PDT. We determined the fluorescence intensity of PpIX in HCC and nontumoral tissue in the liver. 5-Aminolaevulinic acid was intravenously injected to male Fisher rats with HCC at a dose of 500 mg x kg(-1), and the fluorescence intensity in each tissue sample excised from liver was measured with a spectrofluorometer at 1, 3 and 6 h after administration. Fluorescence intensity was at a peak of 3 h after administration in both HCC and nontumoral tissue. The accumulation of PpIX in HCC was higher than that in the nontumoral tissue at 1 h (P<0.001) and 3 h (P<0.05) after ALA administration. Based on these results, PDT was performed on HCC at 3 h after 500 mg x kg(-1) ALA administration before laser irradiation of 30 J per tumour. Antitumour effect was more evident in HCC than in the nontumoral tissue surrounding HCC. These findings suggest the possibility to detect HCC by fluorescence and to treat HCC by light.

An inferior mesenteric-caval shunt via the internal iliac vein with portosystemic encephalopathy.

We report here a case of an unusual extrahepatic portosystemic venous shunt in a 37-year-old woman without liver cirrhosis or portal hypertension, who developed portal systemic encephalopathy. Angiography demonstrated an inferior mesenteric-caval shunt characterized by the presence of direct communication of the inferior mesenteric vein with the left internal iliac vein. After the treatment with percutaneous transcatheter embolization of the shunt via a femoral vein approach using coils, she had no episode of portal systemic encephalopathy.

[A study of institutional medical care of female victims of sexual assault and violence].

OBJECTIVE: The purpose of the study is to clarify the present situation of medical care for victims of sexual assault and violence. Medical facilities in two wards in Tokyo were studied in order to know what problems regarding medical care exist and how to support female victims. METHODS: In April 1998, we distributed questionnaires to 338 medical facilities covering all the clinics and hospitals, that had more than only otorhinolaryngology and ophthalmology, in Kouto-ku and Sumida-ku, Tokyo. The questionnaire included questions about individual experience of consulting with sexual assault and violence against women, the number of victims in the last year, and their understandings for victims. RESULT: 1) 76 of the respondents completed the answer sheet by themselves. The mean age of the subjects was 57.4 years old, 16.3% of them had seen sexual assault victims, and about 36.8% had cared for victims of violence. 2) 67 victims of sexual assault and violence were reported in the previous year. 36% of victims of sexual assault were reported by facilities related to obstetrics, and 85% of victims of violence were reported by general medical facilities. 3) As for understandings for victims, those who thought the victims were responsible for the sexual assault also regarded violence as caused by carelessness of victims. CONCLUSION: Medical facilities may be an important place to care for victims of sexual assault and violence against women. There are few data available as to how many women suffer from sexual violence. This study showed for the first time the reality of sexual assault and violence from the viewpoints of medical facilities in Japan, although it had some limitations. It is necessary for more discussion about roles of medical care for female victims of sexual assault and violence.

Changes in the pattern of growth in stature related to prenatal exposure to ionizing radiation.

PURPOSE: To examine the pattern and spurt in growth and development of prenatally exposed atomic-bomb survivors and to determine whether a statistically significant radiation-related growth retardation exists. MATERIALS AND METHODS: The stature of 1566 individuals exposed prenatally to the atomic bombings has been employed to study the effect of such exposure on growth. Among these survivors, 30 were severely mentally retarded, and 66 individuals on whom no physical measurements between ages 9 and 19 exist were excluded from this study. Thus this analysis rests on the measurements obtained on 1470 survivors 9 to 19 years of age at the time of examination. RESULTS: When the > or =0.50 Sv group was compared to the other two prenatally exposed groups, a significant retardation of growth was observed only among those survivors exposed in the first trimester of gestation. The onset of the growth spurt among males in the three exposure groups was at approximately the same age, 11.34 years, but this was not true in females. The maximum velocity in growth for males was at 14.38 years of age, but for females no clear peak velocity was demonstrable. CONCLUSION: A radiation-related growth retardation was demonstrable in this longitudinal study of the stature of individuals prenatally exposed. It is further demonstrated that among these survivors the growth velocity was faster in the high-dose group than in the low-dose group for both males and females.

Cognitive function and prenatal exposure to ionizing radiation.

It is clear from the many studies of the prenatally exposed survivors of the atomic bombing of Hiroshima and Nagasaki that exposure to ionizing radiation during gestation has harmful effects on the developing human brain, particularly if that exposure occurs at critical stages in the development of the neocortex. Data on a variety of measures of cognitive function, including the occurrence of severe mental retardation as well as variation in the intelligence quotient (IQ) and school performance, show significant effects on those survivors exposed 8-15 weeks and 16-25 weeks after ovulation. Studies of seizures, primarily those without known precipitating cause, also exhibit a radiation effect on those individuals exposed in the first 16 weeks after ovulation. The cellular and molecular events that subtend these abnormalities are still largely unknown although some progress toward an understanding has occurred. For example, magnetic resonance imaging of the brain of some of the mentally retarded survivors has revealed a large region of abnormally situated gray matter, suggesting an abnormality in neuronal migration, but cell killing could also contribute importantly to the effects on cognitive function that have been seen. The retardation of growth in stature observed in individuals exposed in the first and second trimesters of pregnancy suggests that the development of an atypically small head size, without conspicuously impaired cognitive function, may reflect a generalized retardation of growth.

Radiation-related brain damage and growth retardation among the prenatally exposed atomic bomb survivors.

Many studies of prenatally exposed survivors of the atomic bombings of Hiroshima and Nagasaki have shown that exposure to ionizing radiation during gestation has harmful effects on the developing human brain. Data on the occurrence of severe mental retardation as well as variation in intelligence quotient (IQ) and school performance show significant effects on those survivors exposed 8-15 and 16-25 weeks after ovulation. Studies of seizures, especially those without a known precipitating cause, also exhibit a radiation effect in survivors exposed 8-15 weeks after ovulation. The biologic events that subtend these abnormalities are still unclear. However, magnetic resonance imaging of the brains of some mentally retarded survivors has revealed a large region of abnormally situated gray matter, suggesting an abnormality in neuronal migration. Radiation can induce small head size as well as mental retardation, and a review of the relationship between small head size and anthropometric measurements, such as height, weight, sitting height and chest circumference, shows that individuals with small head size have smaller anthropometric measurements than normocephalics. This suggests that radiation-related small head size is related to a generalized growth retardation. Finally, the issue of a threshold in the occurrence of one or more of these effects, both heuristically and from a regulatory perspective, remains uncertain. Simple inspection of the data often suggests that a threshold may exist, but little statistical support for this impression can be advanced, except in the instance of mental retardation.

Preventive effects of polysaccharides extracted from human tubercle bacilli (specific substance of Maruyama) on colonic carcinogenesis in rats.

Polysaccharides extracted from human tubercle bacilli (specific substance of Maruyama [SSM]) have been clinically applied with satisfactory results. Thymidylate synthetase (TS) and thymidine kinase (TK) are key enzymes in de novo and salvage pathways for pyrimidine nucleotide synthesis. Well- and moderately well differentiated adenocarcinomas induced with 1,2-dimethylhydrazine (DMH) are widely distributed throughout the colorectal tract with high TK activity, and the poorly differentiated type is mainly restricted in the proximal colon and the cecum with high TS activity in rats. Subcutaneously injecting the rats with SSM reduced TS activity in colonic nontumorous regions, but in the tumorous regions it reduced TK activity compared with that of the DMH-treated rats without SSM treatment. SSM is suggested to reduce the colorectal carcinogenesis induced with DMH by inhibiting DNA synthesis in a de novo pathway, and to suppress the development of the tumors by decreasing DNA synthesis in the salvage pathway in rats.

Threshold for radiation-related severe mental retardation in prenatally exposed A-bomb survivors: a re-analysis.

Significant effects on the developing human brain of exposure to ionizing radiation are seen among individuals exposed in the 8th-25th week after ovulation. These effects, particularly in the highly vulnerable period of 8-15 weeks after ovulation, manifest themselves most dramatically as an increased frequency of severe mental retardation. However, the distribution of cases of severe mental retardation suggests a threshold in the low-dose region. The 95% lower bound of the threshold in those survivors exposed 8-15 weeks after ovulation was zero for the individual data based on the simple linear model, and 0.15 Gy based on the exponential linear model used in our previous report (1987), but the 95% lower bound of the threshold based on all of the data including 21 additional cases with known doses appears to be 0.05 Gy using the maximum likelihood estimates derived from an exponential-linear model. The latter model was selected because it provides the best fit from the standpoint of the stableness and reasonableness of the estimates among the five models applied to the data. When two probably non-radiation-related cases of Down's syndrome are excluded from the 19 mentally retarded cases exposed 8-15 weeks post ovulation, the 95% lower bound of the threshold is in the range of 0.15-0.25 Gy based on the exponential-linear model used in 1987, but is in the range of 0.06-0.31 Gy when the more reasonable and better model applied here is used. For exposure in the 16-25-week period based on the same model, the 95% lower bound of the threshold changed from 0.25 to 0.28 Gy, both with and without inclusion of the two probable non-radiation-related mentally retarded cases; one of these cases was probably familial in origin since there was a retarded sibling, and the other due to infection, since the individual had Japanese B encephalitis at age 4 years.

Cataract in atomic bomb survivors based on a threshold model and the occurrence of severe epilation.

This report re-examines the relationship of radiation dose to the occurrence of cataracts among 1742 atomic bomb survivors seen in the years 1963-1964 for whom the degree of epilation and Dosimetry System 1986 (DS86) doses are known. Of these individuals, 67 had cataracts. A relative risk model with two thresholds, one for the epilation group and the other for the no-epilation group, has been fitted to the data using a binomial odds regression approach and a constant relative biological effectiveness (RBE) for neutrons of 10. Among these models, a linear-linear (L-L) dose-response relationship with two thresholds presents the best fit. Under the L-L threshold model based on DS86 eye organ dose estimates for the epilation and no-epilation groups, the slope estimate for the epilation group was 1.6-2.0 times greater than that for the no-epilation group, but no statistical difference between the two slope estimates was noted. The estimated threshold for the epilation group was 0.86 Sv and 1.54 Sv for the no-epilation group, but again the difference between the two threshold estimates is not statistically significant. When an L-L relative risk model with two thresholds was fitted to the data assuming the dose estimates to be in error by 35%, or when the data were restricted to the 1105 individuals exposed in Japanese houses at distances of less than 2500 m, where the DS86 doses are thought to be most reliable, the results were almost the same as those for the individuals for whom unadjusted DS86 eye organ dose estimates were used.

Acute disseminated encephalomyelitis associated with Mycoplasma pneumoniae infection.

An 8 year old girl with acute disseminated encephalomyelitis (ADEM) is described. Elevated serum antibody titers suggested recent Mycoplasma pneumoniae infection. T2-weighted image of magnetic resonance imaging (MRI) disclosed multiple lesions of high signal intensity in bilateral basal ganglia and thalami as well as in the white matter. Postcontrast T1-weighted image revealed an enhanced lesion in the deep white matter. She showed rapid clinical improvement in response to corticosteroid therapy. The lesions had disappeared completely on MRI performed 10 weeks after the onset. ADEM is believed to be a demyelinating disorder of probable autoimmune etiology. MRI findings in this case may support the hypothesis that the primary pathological event is vascular injury and demyelination occurs only as a secondary phenomenon.

Relationship between cataracts and epilation in atomic bomb survivors.

Among 1713 atomic bomb survivors who underwent ophthalmological examinations from 1963-1964, the risk of cataract formation per unit dose of radiation was significantly greater for those who reported hair loss of 67% or more after exposure (the epilation group) than for those who reported less or no hair loss (the no-epilation group) (P < 0.01). Such an epilation effect has also been associated with leukemia mortality and the frequency of chromosome aberrations. Although this might be interpreted as indicating differential sensitivity to radiation between the epilation group and the no-epilation group, it could also be explained by imprecision in dose estimates. We have calculated that a 48% random error in DS86 dose estimates could be in accordance with the dose-response relationship for the prevalence of cataracts in the epilation group or the no-epilation group. Possible mechanisms for variation in radiosensitivity are discussed.

Further observations on abnormal brain development caused by prenatal A-bomb exposure to ionizing radiation.

The pervasiveness of abnormal brain development caused by prenatal exposure to ionizing radiation is still largely unknown. The relationship between A-bomb radiation dose and two measures of neuromuscular performance, one of grip strength and the other of the fine motor coordination required in repetitive action, is described. A multivariate analysis of covariance was used to evaluate the effect of several covariates, such as prenatal radiation exposure and some physical measurements or IQ adding city and sex as categorical factors. When mentally retarded cases were included, a statistically significant effect of radiation exposure on the grip strength and repetitive-action test scores was seen in the 8-15-week postovulation period, and a statistically suggestive effect at 16-25 weeks postovulation. No effect of radiation exposure on the two test scores was noted for prenatal exposure in either of the aforementioned periods when mentally retarded cases were excluded, but a statistically significant diminution of IQ was noted for exposures > or = 16 weeks postovulation. We discuss, from the biological perspective, the projected standard scores for exposures > or = 16 weeks postovulation, and the possibility of lower IQ, small head and mild mental retardation related to radiation exposures < or = 15 weeks postovulation with mentally retarded cases excluded.

Evidence of radiation-induced reduction of height and body weight from repeated measurements of adults exposed in childhood to the atomic bombs.

Reduction of growth from exposure to atomic bomb radiation has been examined using individuals under 10 years old at the time of the bombing (ATB) and a growth curve analysis based on measurements of height and weight made in the course of the 4th-7th cycles of the Adult Health Study examinations (1964-1972). As expected, the largest difference in growth to emerge is between males and females. However, a highly significant reduction of growth associated with dose (DS86) was observed among those survivors for whom four repeated measurements of height and weight were available. Longitudinal analysis of a more extended data set (n = 821), using expected values based on simple linear regression models fitted to the three available sets of measurements of height and weight on the 254 individuals with a missing measurement, also indicates a significant radiation-related growth reduction. The possible contribution of such factors as poor nutrition and disruption of normal family life in the years immediately after the war is difficult to evaluate, but the effects of socioeconomic factors on the analysis of these data are discussed.

Effects of environmental factors on perinatal outcome: neurological development in cases of intrauterine growth retardation and school performance of children perinatally exposed to ionizing radiation.

We performed two studies to investigate environmental factors in relation to neurological development in infants. The first, a field study, examined the elementary school performance of 929 children who were born from mothers exposed to the atomic bombing of Hiroshima, Japan, August 6, 1945. The most severe mental retardation was observed in the group exposed between 8 and 15 weeks following fertilization, and the second most severely damaged group was exposed between 16 and 25 weeks. The second, a clinical investigation, examined infants in the perinatal center who survived intrauterine growth retardation (IUGR). Those who survived with abnormal neurological development had a mean growth arrest corresponding to a uterine height of 27 weeks of gestation. This was at an earlier stage than those who survived with normal neurological development and had a mean growth arrest corresponding to 29-30 weeks of gestation. A smaller head circumference at birth was closely correlated with abnormal neurological sequelae. These results indicate that the brain development of the fetuses may have been affected by neurotoxic events similar to ionizing radiation. We emphasize the importance of avoiding neurotoxic stress to pregnant women when the fetus is in the critical period of neuronal development, before 27 weeks of gestational age.

A longitudinal study of growth and development of stature among prenatally exposed atomic bomb survivors.

Growth retardation due to exposure to the atomic bomb has been evaluated using repeated measurements of stature from 10 to 18 years of age. A highly significant growth retardation due to the DS86 uterine dose was observed in all trimesters combined and in the first and second trimesters of pregnancy. In the first trimester, all parameter estimates based on a linear (L) or linear-quadratic (L-Q) dose-response relationship were negative in relation to the DS86 uterine dose. The positive dose estimate in the second trimester is small and close to the control level. Statistically significant difference was determined by a multivariate test statistic examining whether or not a set of two- or three-parameter estimates including a constant term related to an L or L-Q dose-response relationship was different from zero. A radiation-related growth retardation was demonstrable as a longitudinal result of the repeated measurements of stature. The dose effect in the third trimester was not significant under either the L or the L-Q model. The relationship between birth weights and repeated measurements of stature in adolescence is discussed based on the results obtained by a growth curve analysis.

Radiation-related small head sizes among prenatally exposed A-bomb survivors.

Of 1566 individuals prenatally exposed to the atomic bombings of Hiroshima and Nagasaki, 1473 had the circumference of their head measured at least once between ages 9 and 19. Among these 1473 individuals, 62 had small heads--the circumference of the heads was two standard deviations or more below the observed specific-age-at measurement mean. Of 26 cases with severe mental retardation, 15 (58%) had small heads. Most (86%) of the individuals with small heads were exposed in the first trimester (about < 12 weeks postovulation) or second trimester (about 12-24 weeks postovulation)--55% in the former period and 31% in the latter. Various dose-response relationships, with and without a threshold, have been fitted to the data grouped by the trimester or postovulatory age (weeks after ovulation) at which exposure occurred. A significant effect of radiation on the frequency of individuals with atypically small heads is observed only in the first and second trimesters and for the intervals postovulation of 0-7 weeks and 8-15 weeks. Although the risk of a small head at 0-7 weeks postovulation increases significantly with increasing dose, no increase in risk for severe mental retardation is noted in this period. No excess risk of a small head was seen in the third trimester (about > or = 25 weeks postovulation) or among individuals exposed at 16 weeks or more postovulation. The mean IQ values of mentally retarded cases with and without small heads were 63.8 and 68.9, respectively. No significant difference exists between these two IQ means, but both were significantly smaller than 96.4, the IQ value for individuals with small heads without severe mental retardation and 107.8, the value for the overall sample.

Radiation-related ophthalmological changes and aging among Hiroshima and Nagasaki A-bomb survivors: a reanalysis.

The relationship of ionizing radiation to the age-related ophthalmological findings of the 1978-1980 ophthalmological examination of A-bomb survivors of Hiroshima and Nagasaki has been reanalyzed using DS86 eye organ dose estimates. The main purpose of this reevaluation was to determine whether age and radiation exposure, as measured using the recently revised dosimetry information (DS86), have an additive, synergistic, or antagonistic effect. The data in this study are limited to axial opacities and posterior subcapsular changes, for which a definite radiation-induced effect has been observed in Hiroshima and Nagasaki A-bomb survivors. The best model fitting for axial opacities gives a significant positive effect for both linear dose and linear age-related regression coefficients and a significant negative effect for an interaction between radiation dose and age. Such a negative interaction implies an antagonistic effect in that the relative risks in relation to radiation exposure doses become smaller with an increase in age. On the other hand, the best-fitting relationship for posterior subcapsular changes suggested a linear-quadratic dose and linear age-related effect. The estimate of the quadratic dose coefficient shows a highly negative correlation with age, but the negative quadratic dose term is extremely small and is of little biological significance.

Effect of Nocardia rubra cell-wall skeleton on cancer prevention in humans.

The retired workers at the chemical weapons plant in Japan are regarded as a high-risk group for cancers. Under the Cancer Preventive Program, Nocardia rubra cell-wall skeleton (N-CWS) was administered to 80 workers directly involved in the production of sulfur mustard and 66 workers engaged in work related to sulfur mustard production. Untreated workers whose age, sex, duties and duration of work at this factory were individually matched to the N-CWS-treated workers were used as controls. During a 4.5-year observation period, development of cancers was found in 7 treated workers and 17 untreated controls. After elimination of the influence of the difference in smoking level, the incidence of subjects who developed cancers was compared statistically between the N-CWS-treated workers and the untreated controls and a significant suppression of development of cancers was noted in the N-CWS-treated workers. Thus, it was concluded that the administration of N-CWS could prevent cancer development in humans.

[Effect on school performance of prenatal exposure to the Hiroshima atomic bomb].

As a part of the continuing assessment of the effects on the developing embryonic and fetal brain of exposure to ionizing radiation, the school performance of prenatally exposed survivors of the atomic bombing of Hiroshima and a suitable comparison group have been studied. In this report, the changes in performance in seven school subjects according to dose are compared under the dosimetry system (DS86) instituted in 1986 at the Radiation Effects Research Foundation. The sample involves 929 children whose fetal absorbed dose are known and includes 14 severely mentally retarded persons. The findings can be summarized as follows: 1) Damage to the 8-15 week fetal brain appears to be linearly related to the absorbed dose, as judged by the simple regression of average school-performance score on dose. Damage to the fetus exposed at 16-25 weeks after fertilization appears similar to that seen in the 8-15 week group. Canonical and multiple correlations also show a highly significant relationship of exposure 8-15 weeks and 16-25 weeks after fertilization to achievement in school. This trend is stronger, however, in the earliest years of schooling. 2) In the group exposed within 0-7 weeks following fertilization, or 26 or more weeks after fertilization, there was no evidence of a radiation-related effect on scholastic performance. 3) These results parallel those previously found in prenatally exposed survivors with respect to achievement in standard intelligence tests in childhood and development of severe mental retardation.