62 research outputs found

    Upper Limit on the Cosmological Gamma-ray Background

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    We show that the current extragalactic gamma-ray background (EGB) measurement below 100 GeV sets an upper limit on EGB itself at very high energy (VHE) above 100 GeV. The limit is conservative for the electromagnetic cascade emission from VHE EGB interacting with the cosmic microwave-to-optical background radiation not to exceed the current EGB measurement. The cascade component fits the measured VHE EGB spectrum rather well. However, once we add the contribution from known source classes, the Fermi VHE EGB observation exceeds or even violates the limit, which is approximated as E^2dN/dE < 4.5x10^-5 (E/100 GeV)^-0.7 MeV/cm^2/s/sr. The upper limit above 100 GeV is useful in the future to probe the EGB origin and the new physics like axion-like particles and Lorentz-invariance violation.Comment: 8 pages, 8 figures, accepted for publication in PRD, Interested readers may wish to consult the recent paper by Murase, Beacom and Takami (arXiv:1205.5755

    Association of clinical findings in Yusho patients with serum concentrations of polychlorinated biphenyls, polychlorinated quarterphenyls and 2,3,4,7,8-pentachlorodibenzofuran more than 30 years after the poisoning event

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    <p>Abstract</p> <p>Background</p> <p>The Yusho poisoning incident, which was caused by rice bran oil contaminated with polychlorinated biphenyls (PCBs), polychlorinated quarterphenyls (PCQs) and polychlorinated dibenzofurans (PCDFs) generated by heat denaturation of PCB, occurred in 1968 in western Japan. Annual physical, dermatological, dental, ophthalmological and laboratory examinations were conducted for Yusho patients after the incident. From 2001, blood levels of individual PCDF congeners were also measured. The blood levels of 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PeCDF), PCBs and PCQs in Yusho patients were found to be significantly higher than those of the general population. We investigated the relationships between blood concentrations of 2,3,4,7,8-PeCDF, PCBs and PCQs in Yusho patients and the items measured in the annual medical examination.</p> <p>Methods</p> <p>Medical and laboratory examination data from 501 Yusho patients enrolled in the study from 2001 to 2004 were analyzed. The relationships between blood 2,3,4,7,8-PeCDF, PCB and PCQ concentrations and medical/laboratory examination data were investigated using principal components and logistic regression analyses.</p> <p>Results</p> <p>Serum Concentrations of 2,3,4,7,8-PeCDF, PCBs and PCQs in blood tended to correlate with either acneform eruptions, black comedones, cutaneous and mucosal pigmentation, and hypersecretion of meibomian glands as well as general fatigue, headaches, cough/sputum, abdominal pain, arthralgia, increased blood sugar, increased serum γ-GTP and decreased total bilirubin. The majority of these signs and symptoms are included in the diagnostic criteria for Yusho.</p> <p>Conclusion</p> <p>After Yusho patients had suffered chronic exposure to these chlorinated compounds for more than 35 years, the serum concentration of 2,3,4,7,8-PeCDF in blood was significantly related to arthralgia and decreased albumin/globulin (A/G) ratio; the serum concentration of PCBs was significantly related to ophthalmologic symptoms; and the serum concentration of PCQ to increased total cholesterol. These findings suggest that the co-contaminants may affect other functions than those originally associated with Yusho.</p

    血中の2,3,4,7,8-五塩化ダイベンゾフラン(PeCDF)の個人の半減期:油症患者における臨床症状並びに検診結果との関係

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    BACKGROUND: In 1968, many people developed dioxin poisoning (Yusho) in Japan. Ingestion of 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PeCDF) was considered to be the cause of this poisoning. Although some patients had high concentrations of 2,3,4,7,8-PeCDF in their blood, individuals' half-lives of 2,3,4,7,8-PeCDF were long. OBJECTIVES: To evaluate the relationship between clinical and laboratory parameters and the individual half-life of 2,3,4,7,8-PeCDF in blood. METHODS: Clinical and laboratory data were collected during annual check-ups from 2001 to 2008. We enrolled 71 patients, who were measured more than 3 times, and who had 2,3,4,7,8-PeCDF concentrations in blood >50pgg(-1) lipid. The half-life of 2,3,4,7,8-PeCDF for each patient was estimated using linear regression. Moreover, relationships between clinical and laboratory parameters and individual half-life were investigated by linear regression. RESULTS: A shortened individual half-life for 2,3,4,7,8-PeCDF was significantly correlated with an increased red blood cell count, increased viscous secretions from the meibomian glands, existing black comedones, and severe cedar pollen allergy. CONCLUSIONS: Symptoms that accelerate excretion of lipids from the body, such as viscous secretions from the meibomian glands, may lead to a shorter half-life of 2,3,4,7,8-PeCDF. Red blood cells are related to the half-life of 2,3,4,7,8-PeCDF. However, further studies are required to investigate the excretory mechanism of 2,3,4,7,8-PeCDF.博士(医学)・乙1325号・平成26年3月17

    Cutaneous symptoms such as acneform eruption and pigmentation are closely associated with blood levels of 2,3,4,7,8-penta-chlorodibenzofurans in Yusho patients, using data mining analysis

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    <p>Abstract</p> <p>Background</p> <p>Yusho an intoxication caused by oral dioxins and polychlorinated biphenyls occurred in 1968. Patients suffered from various systemic symptoms, including general fatigue, nausea, muscular and articular pain, acneform eruptions, black comedones, cutaneous and oral pigmentation, and increased eye discharge. The major causative factor was the contamination of rice oil with 2,3,4,7,8-penta-chlorodibenzofuran (PeCDF). Recent technical advances have allowed us to measure blood levels of PeCDF. However, there is little information on which symptoms and laboratory data are directly associated with PeCDF levels.</p> <p>Methods</p> <p>Yusho patients underwent annual medical check-ups from 2001 to 2003. Blood PeCDF levels were correlated with the presence or absence of symptoms in medical, hematological, dermatological, dental and ophthalmological examinations. This study analyzed all combinations by using the association analysis. This is the most suitable method to evaluate all combinations of the data comprehensively. This method was used to determine the rate of patients with high PeCDF level in the population with each symptom, and to extract combinations of three symptoms which were strongly associated with high PeCDF level.</p> <p>Results and Conclusion</p> <p>The rate of the patients with high PeCDF level was high in populations with high uric acid, black comedones (face), second highest quartile of age, or high urea nitrogen. The combination of three symptoms associated with the highest rate of patients with high PeCDF level was "high uric acid, female sexuality, and history of acneform eruptions", followed by "history of Yusho in and after 1968, high cholesterol level, and subjective symptoms." This analysis newly suggested that PeCDF concentration may be associated with history of dermatological symptoms, high uric acid, and elevated erythrocyte sedimentation rate.</p

    EFFECTS OF LH-RH ANALOGUE ON THE OVULATION RATE AND EMBRYO QUALITY IN HEIFERS SUPEROVULATED WITH PMSG AND PGF_2α

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    Eighty-four Holstein-Friesian virgin heifers were superovulated with either 2500 or 3000 IU of PMSG in addition to 30 mg of PGF_2α. The heifers were divided into two groups. Approximately half of them were administered LH-RH analogue twice at 1.5 hour intervals during the superovulatory estrus (treated), and the remaining animals were not treated with LH-RH analogue (control). Nonsurgical embryo recovery was performed 7 or 8 days after estrus. In the control heifers, effects of the dose of PMSG were examined, and it was found that by increasing the dose from 2500 to 3000 IU, a significantly larger number of corpora lutea and total number of eggs were observed (P<0.05). However, the number of good embryos was not increased. These effects of LH-RH analogue were analyzed by comparing the treated and the untreated control heifers following the injection of the same dose of PMSG. The treatment with LH-RH analogue was effective in increasing significantly the number of ovulations and the total number of eggs and good embryos recovered (P<0.05) when the heifers also received 2500 IU of PMSG. The heifers received 3000 IU of PMSG did not show significant responses to LH-RH analogue, but the tendency of a higher percentage of good embryos was recorded

    INDUCTIONS OF SUPEROVULATION USING SEVERAL FSH REGIMENS IN HOLSTEIN-FRIESIAN HEIFERS

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    Eighty-three Holstein-Friesian virgin heifers were randomly divided into four groups and superovulated with one of the four FSH regimens as follows : Group I) twice daily injections of a constant dose of 5 mg of FSH for a period of 4 days, giving a total dose of 40 mg in 8 fractions ; Group II) as in Group I with additional 5 mg of FSH on the 5th day, giving a total dose of 45 mg ; Group III) twice daily injections on a decreasing dose regimen of 5,4,3 and 2 mg successively for 4 days with the addition of 2 mg of FSH once on the 5th day, giving a total dose of 30 mg; Group IV) similar to Group III, but a mixture of FSH and LH in the ratio of 5 : 1 was used, giving a total dose of 30 mg of FSH and 6 mg of LH in 9 fractions. Nonsurgical embryo recovery was performed 7 or 8 days after estrus. Percentage of good embryos in Group II was significantly greater than that in Group I (P<0.05). There was no significant difference between Groups II and III in any of the criteria analyzed. Group IV was superior to the other groups in superovulation rate and embryo yielding. Significantly greater numbers of total eggs and good embryos were observed in Group IV compared to those in Groups I and II (P<0.05). Percentage of the heifers with more than 3 good embryos in Group IV was significantly higher than that in Groups I , II and III (P<0.05)

    HISTOCHEMICAL OBSERVATIONS OF LIPID DROPLETS IN MOUSE EMBRYOS

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    Morphology of lipid droplets in 313 embryos of different developmental stages was examined. Embryos were obtained from spontaneously ovulated and superovulated mice of ddY strain. Sudan III was used to stain embryos so as to count the number of lipid droplets. Lipid droplets were classified into three groups according to the diameter : small (≦ 1.0μm), medium (1.1-3.0μm) and large (3.1-5.0μm). From the 2-cell stage to the expanded blastocyst, lipid droplets were found to be abundant. Numerous small lipid droplets were observed in all developmental stages. The number of medium and large lipid droplets increased with the development of embryos. The numbers of medium lipid droplets in the embryos at the 2-cell stage, 8-cell stage and expanded blastocyst were 0.5±0.4,11.2±3.3 and 60.3±3.2,respectively. Large lipid droplets were not observed in the 2-cell and 4-cell stages, but were found to be abundant in the morula and blastocyst. A sudden and significant increase in the number of medium and large lipid droplets was observed from the 8-cell stage to the morula (p<0.01). Similar increase of lipid droplets was also observed in morulae developed from 8-cell embryos in in vitro culture (p<0.01). The number of lipid droplets in expanded blastocysts was not affected by the ovulation methods
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