Vertical Distribution and Estimated Doses from Artificial Radionuclides in Soil Samples around the Chernobyl Nuclear Power Plant and the Semipalatinsk Nuclear Testing Site

For the current on-site evaluation of the environmental contamination and contributory external exposure after the accident at the Chernobyl Nuclear Power Plant (CNPP) and the nuclear tests at the Semipalatinsk Nuclear Testing Site (SNTS), the concentrations of artificial radionuclides in soil samples from each area were analyzed by gamma spectrometry. Four artificial radionuclides (²⁴¹Am, ¹³⁴Cs, ¹³⁷Cs, and ⁶⁰Co) were detected in surface soil around CNPP, whereas seven artificial radionuclides (²⁴¹Am, ⁵⁷Co, ¹³⁷Cs, ⁹⁵Zr, ⁹⁵Nb, ⁵⁸Co, and ⁶⁰Co) were detected in surface soil around SNTS. Effective doses around CNPP were over the public dose limit of 1 mSv/y (International Commission on Radiological Protection, 1991). These levels in a contaminated area 12 km from Unit 4 were high, whereas levels in a decontaminated area 12 km from Unit 4 and another contaminated area 15 km from Unit 4 were comparatively low. On the other hand, the effective doses around SNTS were below the public dose limit. These findings suggest that the environmental contamination and effective doses on the ground definitely decrease with decontamination such as removing surface soil, although the effective doses of the sampling points around CNPP in the present study were all over the public dose limit. Thus, the remediation of soil as a countermeasure could be an extremely effective method not only for areas around CNPP and SNTS but also for areas around the Fukushima Dai-ichi Nuclear Power Plant (FNPP), and external exposure levels will be certainly reduced. Long-term follow-up of environmental monitoring around CNPP, SNTS, and FNPP, as well as evaluation of the health effects in the population residing around these areas, could contribute to radiation safety and reduce unnecessary exposure to the public.     

Changes of Linoleic,Arachidonic and Eicosapentaenoic Acids in Rat Platelet,Aorta and Plasma Lipids after Changing from a Sardine Oil Diet to a Corn Oil Diet

When rats were fed on a diet containing sardine oil (SO) for 10 days, 20:5 (eicosapentaenoic acid) was incorporated into the platelet, aorta and plasma lipids. The 20:5/20:4 (arachidonic acid) ratios of phospholipids were higher in platelets than in aortas. When the diet was changed from SO to corn oil (CO), the levels of 20:5 in the plasma lipids and platelet phospholipids decreased with an increase of 20:4. Although the 20:5 levels of phospholipids in the aortas decreased, 20:4 did not increase during feeding with the CO diet for 4 days. The 20:5/20:4 ratios of the phosphatidylcholine in platelets and aortas rapidly changed from 5.0 and 1.1 to 2.4 and 0.6, respectively. The linoleic acid level of phosphatidylcholine in platelets and aortas increased rapidly by changing from the SO diet to the CO diet, but this fatty acid was not incorporated into phosphatidylinositol of the platelets and aortas.     

Studies on the Induced Synthesis of Maleate cis-trans Isomerase by Malonate

Maleate cis-trans isomerase in Alcaligenes faecalis IB–14 was induced by malonate and purified about 100-fold over the crude cell-free extract by treatments of ammonium sulfate fractionation, Sephadex G–100 gel filtration, DEAE-cellulose and DEAE-Sephadex A–50 column chromatography. The preparation was shown to be monodisperse on ultracentrifugal analysis and Svedberg value was found to be 3.84 S.

The enzyme was most active at pH value around 8.3 and was stable over the range of pH 5.0 to 7.0 in the presence of dithiothreitol (DTT) for a few weeks, but in the absence of it, the enzyme activity was markedly decreased, especially in the alkaline region. The enzyme activity was inhibited by various sulfhydryl reagents and oxidizing agents, whereas it was not affected by metal chelating agents. The inhibition by Hg²⁺ and PCMB was overcome by the addition of sulfhydryl compounds such as DTT, 2-mercaptoethanol, l-cysteine and glutathione. It was observed that the enzyme did not require co-factor for its function.

Kinetic studies showed that Michaelis constant for maleate was 2.8×10^?3 m and the enzyme did not catalyze the reverse reaction.     

Relationship between adult height and body weight and risk of carotid atherosclerosis assessed in terms of carotid intima-media thickness: The Nagasaki Islands study

Background

Previous studies have reported an inverse association between height and risk of cardiovascular disease. However, evidence is limited for the association between risk of atherosclerosis and height. Further, although the association between atherosclerosis and body mass index (BMI) is reportedly positive, there have been no reports of studies on associations between height and atherosclerosis in relation to BMI.

Methods

We conducted a cross-sectional study of Japanese men aged 30 to 89 years undergoing general health check-ups.

Results

Of the 1,337 men, 312 were diagnosed with carotid atherosclerosis (carotid intima-media thickness (CIMT) ≥ 1.1 mm), but no significant association was found between height and carotid atherosclerosis for the entire study group. Stratification by BMI status of those analytical findings disclosed a significant inverse association between height and carotid atherosclerosis among overweight (BMI ≥ 25 kg/m²) but not among non-overweight (BMI < 25 kg/m²) men. The classical cardiovascular risk factors-adjusted odds ratio (OR) and 95% confidence interval (CI) of carotid atherosclerosis for an increment of one SD (standard deviation) in height (6.70 cm) were 0.71 (0.54 to 0.94) for overweight (BMI ≥ 25 kg/m²) and 1.05 (0.87 to 1.27) for non-overweight (BMI < 25 kg/m²) men.

Conclusion

Independent from classical cardiovascular risk factors, height was found to be inversely associated with carotid atherosclerosis for overweight but not for non-overweight men.     

Phylogeographic insights into the invasion history and secondary spread of the signal crayfish in Japan

Successful invasion by nonindigenous species is often attributed to high propagule pressure, yet some foreign species become widespread despite showing reduced genetic variation due to founder effects. The signal crayfish (Pacifastacus leniusculus) is one such example, where rapid spread across Japan in recent decades is believed to be the result of only three founding populations. To infer the history and explore the success of this remarkable crayfish invasion, we combined detailed phylogeographical and morphological analyses conducted in both the introduced and native ranges. We sequenced 16S mitochondrial DNA of signal crayfish from across the introduced range in Japan (537 samples, 20 sites) and the native range in western North America (700 samples, 50 sites). Because chela size is often related to aggressive behavior in crayfish, and hence, their invasion success, we also measured chela size of a subset of specimens in both introduced and native ranges. Genetic diversity of introduced signal crayfish populations was as high as that of the dominant phylogeographic group in the native range, suggesting high propagule pressure during invasion. More recently established crayfish populations in Japan that originated through secondary spread from one of the founding populations exhibit reduced genetic diversity relative to older populations, probably as a result of founder effects. However, these newer populations also show larger chela size, consistent with expectations of rapid adaptations or phenotypic responses during the invasion process. Introduced signal crayfish populations in Japan originate from multiple source populations from a wide geographic range in the native range of western North America. A combination of high genetic diversity, especially for older populations in the invasive range, and rapid adaptation to colonization, manifested as larger chela in recent invasions, likely contribute to invasion success of signal crayfish in Japan.     

Flower color modulations of Torenia hybrida by downregulation of chalcone synthase genes with RNA interference

Suppression of biosynthetic genes involved in flower color formation is an important approach for obtaining target flower colors. Here we report that flower color of the garden plant Torenia hybrida was successfully modulated by RNA interference (RNAi) against a gene of chalcone synthase (CHS), a key enzyme for anthocyanin and flavonoid biosynthesis. By using each of the coding region and the 3'-untranslated region of the CHS mRNA as an RNAi target, exhaustive and gene-specific gene silencing were successfully induced, and the original blue flower color was modulated to white and pale colors, respectively. Our results indicate that RNAi is quite useful for modulations of flower colors of commercially important garden plants.     

Secular trends of sizes at birth in Japanese healthy infants born between 1962 and 1988

Body sizes at birth are important clinical indicators widely used for evaluation of prenatal growth. Japan had significant socioeconomic improvement around the 1960s, and these environmental changes may influence physiologically prenatal growth. Furthermore, in Japan, measurements of size at birth for birth certificates are weight and height. Thus, we can refer to annual data on weight and height, but not on head and chest circumference at birth. In this study we measured the weight, height, and head and chest circumference at birth among 6,563 Japanese singleton healthy infants, annually in 1962 and 1988, and examined secular trends of these anthropometric measurements. The boys consistently exceeded the girls in all four variables. Birth weight and height increased significantly from the 1960s to '70s, but did not differ between the '70s and '80s in both boys and girls. Secular trends of head and chest circumference were different from them. In both boys and girls, head and chest circumference increased significantly from the '60s to the '70s, but decreased significantly from the '70s to the '80s. No difference of head circumference during the '60s and '80s was found, but the difference of chest circumference was found. Size at birth was likely to increase from the '60s to '70s in Japan. These findings suggest that the environmental changes such as socioeconomic improvements influence the prenatal growth.     

Extract of Perilla frutescens enriched for rosmarinic acid, a polyphenolic phytochemical, inhibits seasonal allergic rhinoconjunctivitis in humans

Extract of Perilla frutescens enriched for rosmarinic acid, a polyphenolic phytochemical, suppresses allergic immunoglobulin responses and inflammation caused by polymorphonuclear leukocytes (PMNL) in mice. However, few placebo-controlled clinical trials have examined the efficacy and safety of polyphenolic phytochemicals for treatment of allergic inflammatory diseases in humans. The present study determined whether oral supplementation with rosmarinic acid is an effective intervention for patients with seasonal allergic rhinoconjunctivitis (SAR). In this 21-day, randomized, double-blind, age-matched, placebo-controlled parallel group study, patients with mild SAR were treated daily with extract of Perilla frutescens enriched for rosmarinic acid (200 mg [n=10] or 50 mg [n=9]) or placebo (n=10). Patients recorded symptoms daily in a diary. Profiles of infiltrating cells and concentrations of eotaxin, IL-1beta, IL-8, and histamine were measured in nasal lavage fluid. Serum IgE concentrations and routine blood tests were also examined. As compared with placebo supplementation, supplementation with extract of Perilla frutescens enriched for rosmarinic acid resulted in a significant increase in responder rates for itchy nose, watery eyes, itchy eyes, and total symptoms (P<0.05). Active treatment significantly decreased the numbers of neutrophils and eosinophils in nasal lavage fluid (P<0.05 vs. placebo). Patients reported no adverse events, and no significant abnormalities were detected in routine blood tests. In conclusion, extract of Perilla frutescens enriched for rosmarinic acid can be an effective intervention for mild SAR at least partly through inhibition of PMNL infiltration into the nostrils. Use of this alternative treatment for SAR might reduce treatment costs for allergic diseases.     

Synthesis and biological activity of novel alpha-substituted beta-phenylpropionic acids having pyridin-2-ylphenyl moiety as antihyperglycemic agents

We previously reported the identification of novel oximes having 5-benzyl-2,4-thiazolidinedione with antihyperglycemic activity. We now report the synthesis and biological activity of a novel series of oximes and amides having alpha-substituted-beta-phenylpropionic acids. In this series, we obtained potent PPAR alpha/gamma dual agonist (S)-9d, with which activation of PPAR alpha and PPAR gamma was considerably more potent than that of the reference compounds GW9578 22 and rosiglitazone 3, respectively. This means (S)-9d is of the strongest class of PPAR alpha/gamma dual agonists. In the course of this study, we also obtained 8h, which indicated potent plasma glucose lowering effect in spite of weak PPAR alpha/gamma agonistic activity.