Sample records for accidental irradiation-induced aplasia

  1. Spontaneous hematologic recovery from bone marrow aplasia after accidental tenfold overdosage with radiophosphorus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gmuer, J.; Bischof, B.; Coninx, S.

    1983-04-01

    Two patients with polycythemia vera received intravenously an accidental tenfold overdosage of radiophosphorus therapy (60 and 50 mCi 32P, respectively). In both patients, the occurrence of hemorrhagic complications 3 wk after the 32P medication led to detection of the error and referral to our hospital. Upon admission they showed an agranulocytosis, severe thrombocytopenia, and bone marrow aplasia. In both cases, spontaneous recovery of the hematopoiesis was observed from day 40 posttreatment onward. In one patient, a slow but ultimately complete normalization of blood counts and marrow morphology took place, whereas in the other, a mild thrombocytopenia persists. Nearly 5 yrmore » after the accidental overdosage, both patients are clinically well. Symptoms of polycythemia vera have not reappeared up to now. Attempts were made to evaluate the radiation dose absorbed by the bone marrow. In the first patient, the daily 32P excretion was determined from day 22 to day 60, whereas in the other patient a whole body count was performed on day 78 after administration. From these results, an approximate cumulative bone marrow dose of 10 Sv (1000 rem) could be calculated.« less

  2. Noncanonical Wnt5a-Ca(2+) -NFAT signaling axis in pesticide induced bone marrow aplasia mouse model: A study to explore the novel mechanism of pesticide toxicity.

    PubMed

    Chattopadhyay, Sukalpa; Chatterjee, Ritam; Law, Sujata

    2016-10-01

    According to case-control studies, long-term pesticide exposure can cause bone marrow aplasia like hematopoietic degenerative disease leading to impaired hematopoiesis and increased risk of aplastic anemia in human subjects. However, the exact mechanism of pesticide mediated hematotoxicity still remains elusive. In this study, we investigated the role of noncanonical Wnt signaling pathway, a crucial regulator of adult hematopoiesis, in pesticide induced bone marrow aplasia mouse model. Aplasia mouse model was developed following inhalation and dermal exposure of 5% aqueous mixture of common agriculturally used pesticides for 6 h/day for 5 days a week up to 90 days. After that, blood hemogram, marrow smear, cellularity, scanning electron microscopy, extramedullary hematopoiesis and flowcytometric expression analysis of noncanonical Wnt signaling components, such as Wnt 5a, fzd5, NFAT, IFN-γ, intracellular Ca(2+) level were evaluated in the bone marrow hematopoietic stem/progenitor compartment of the control and pesticide induced aplasia groups of animals. Results showed that pesticide exposed mice were anemic with peripheral blood pancytopenia, hypocellular degenerative marrow, and extramedullary hematopoiesis in the spleen. Upon pesticide exposure, Wnt 5a expression was severely downregulated with a decline in intracellular Ca(2+) level. Moreover, downstream of Wnt5a, we observed sharp downregulation of NFATc2 transcription factor expression, the major target of pesticide toxicity and its target molecule IFN-γ. Taken together, our result suggests that deregulation of Wnt5a-Ca(2+) -NFAT signaling axis in the hematopoietic stem/progenitor compartment plays a crucial role behind the pathogenesis of pesticide mediated bone marrow aplasia by limiting primitive hematopoietic stem cells' ability to maintain hematopoietic homeostasis and reconstitution mechanism in vivo during xenobiotic stress leading to ineffective hematopoiesis and evolution of bone marrow aplasia.

  3. Incidental finding of cutaneous meningeal heterotopia in aplasia cutis congenita.

    PubMed

    Kenyon, Katharine; Zedek, Daniel; Sayed, Christopher

    2016-07-01

    Aplasia cutis congenita and cutaneous meningeal heterotopia are both rare congenital conditions that most commonly occur on the scalp and may appear clinically and histologically similar. A subtype of aplasia cutis congenita, membranous aplasia cutis congenita, and cutaneous meningeal heterotopia are both proposed to result from neural tube closure errors. However, neither non-membranous nor membranous aplasia cutis congenita are known to occur together with cutaneous meningeal heterotopia in the same lesion. We report the incidental finding of cutaneous meningeal heterotopia within a lesion of aplasia cutis congenita. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. The role of diclofenack on inducing of aplasia cutis congenita: a case report.

    PubMed

    Pajaziti, Laura; Rexhepi, Syzana; Shatri-Muça, Ylfete; Ferizi, Mybera

    2009-10-12

    Aplasia cutis congenita is a disorder where e newborn child is missing skin from certain areas. It is a rare condition with no particular race or sex more at risk. May occur by itself or be associated with other physical syndromes or disorders. A classification system exists for aplasia cutis congenital consisting of 9 groups, based on the number and location of the skin defects and the presence or absence of other malformations. Causes of aplasia congenital could be heredity, teratogenic substances, placental infarcts, intrauterine infections, ectodermal dysplasias etc. Diagnosis is made based on the clinical findings. Prognosis depends of the other organs malfunction level and lesions size. Our case was an 22 months old Albanian girl, who was recommended to dermatology for a consultation by a pediatric surgeon because of the changes she had on her parietal part of the scalp with missing hair areas. The child has stenosis congenita ani and to her was installed stoma. In order to investigate other accompanied anomalies of the disease, there are made specific consults by neurologist, orthopedist, cardiologist, nephrologists and citogenetics. It was found out a minor visual discoordination, Sy Floppy, Digiti V superductus pedis bill. Laxitas articularum generalisata. It was a great challenge for us to find out that during the first trimester of the pregnancy (unplanned pregnancy), her mother used Diclofenac. Since there is limited information regarding to teratogenic effects of diclofenac, we considered it interesting to present this case.

  5. The role of diclofenack on inducing of aplasia cutis congenita: a case report

    PubMed Central

    2009-01-01

    Background Aplasia cutis congenita is a disorder where e newborn child is missing skin from certain areas. It is a rare condition with no particular race or sex more at risk. May occur by itself or be associated with other physical syndromes or disorders. A classification system exists for aplasia cutis congenital consisting of 9 groups, based on the number and location of the skin defects and the presence or absence of other malformations. Causes of aplasia congenital could be heredity, teratogenic substances, placental infarcts, intrauterine infections, ectodermal dysplasias etc. Diagnosis is made based on the clinical findings. Prognosis depends of the other organs malfunction level and lesions size. Case report Our case was an 22 months old Albanian girl, who was recommended to dermatology for a consultation by a pediatric surgeon because of the changes she had on her parietal part of the scalp with missing hair areas. The child has stenosis congenita ani and to her was installed stoma. In order to investigate other accompanied anomalies of the disease, there are made specific consults by neurologist, orthopedist, cardiologist, nephrologists and citogenetics. Conclusion It was found out a minor visual discoordination, Sy Floppy, Digiti V superductus pedis bill. Laxitas articularum generalisata. It was a great challenge for us to find out that during the first trimester of the pregnancy (unplanned pregnancy), her mother used Diclofenac. Since there is limited information regarding to teratogenic effects of diclofenac, we considered it interesting to present this case. PMID:19946521

  6. [Morphogenesis of vaginal aplasia. Therapeutic deductions].

    PubMed

    Minh, H N; Smadja, A; Belaisch, J

    1985-01-01

    On the basis of the studies of the embryogenesis of the vagina, the authors consider that malformations classically described as being partial aplasia should not be separated from the total absence of the vagina. The important feature is the association of a functioning or non functioning uterus with the absence of the vagina. They believe that it is incorrect to describe the pouch of menstrual retention associated with a functioning uterus as "haematocolpos" and that is not justified to describe the cup-shaped vestibular depression as "hemi-vagina". According to the authors, although vaginal aplasia with a functioning uterus forming a pouch of menstrual retention constitutes an absolute indication for surgery, surgery is not justified in cases of vaginal aplasia with a non functioning uterus. If Frank's method fails in these cases, the patient or the couple should be referred to a sexologist, as women with this anomaly retain a perfect femininity, although unable to conceive.

  7. Dual-Force Vaginoplasty for Treatment of Segmental Vaginal Aplasia.

    PubMed

    El Saman, Ali M; Farag, Mohamad A; Shazly, Sherif A; Noor, Mohamed; Ali, Mohammed K; Othman, Essam R; Khalifa, Mansour; Farghly, Tarek A; El Saman, Dina A

    2017-05-01

    Vaginal aplasia occurs in 1 in 5,000-10,000 female live births. In this report, we evaluated a novel dual-force vaginoplasty technique for treatment of 11 patients with segmental vaginal aplasia. The principle of the approach is to thin the atretic part between two counteracting forces. The instrument was inserted laparoscopically into the proximal hematocolpos. Two balloon catheters, one for drainage and one for traction, were threaded over the inserter. The traction catheter was then threaded over a silicon tube, leaving the balloon in the proximal portion of the vagina and connecting across the vaginal septum to a fenestrated Teflon olive, which was positioned against the distal surface of the vaginal septum. This created a dual "pushing and pulling" force across the septum, which, over 3-4 days, pulls the upper vaginal pouch down while the vaginal dimple is pushed up. The aplastic segment becomes thin and easy to dilate and permits achievement of vaginal patency. The drainage of the hematocolpos is predominantly through the balloon catheter so postoperative wound management is facilitated. Eleven menarchal girls were diagnosed with segmental vaginal aplasia. The dual-force vaginoplasty was performed on each and was tolerated well with no operative complications. They all reported establishment of the menstrual cycle and significant improvement of pain during follow-up. Creation of a dual pushing-pulling force on the atretic vaginal segment is a feasible short procedure for management of segmental vaginal aplasia.

  8. Local irradiation not only induces homing of human mesenchymal stem cells at exposed sites but promotes their widespread engraftment to multiple organs: a study of their quantitative distribution after irradiation damage.

    PubMed

    François, Sabine; Bensidhoum, Morad; Mouiseddine, Moubarak; Mazurier, Christelle; Allenet, Bénédicte; Semont, Alexandra; Frick, Johanna; Saché, Amandine; Bouchet, Sandrine; Thierry, Dominique; Gourmelon, Patrick; Gorin, Norbert-Claude; Chapel, Alain

    2006-04-01

    Mesenchymal stem cells (MSCs) have been shown to migrate to various tissues. There is little information on the fate and potential therapeutic efficacy of the reinfusion of MSCs following total body irradiation (TBI). We addressed this question using human MSC (hMSCs) infused to nonobese diabetic/ severe combined immunodeficient (NOD/SCID) mice submitted to TBI. Further, we tested the impact of additional local irradiation (ALI) superimposed to TBI, as a model of accidental irradiation. NOD/SCID mice were transplanted with hM-SCs. Group 1 was not irradiated before receiving hMSC infusion. Group 2 received only TBI at a dose of 3.5 Gy, group 3 received local irradiation to the abdomen at a dose of 4.5 Gy in addition to TBI, and group 4 received local irradiation to the leg at 26.5 Gy in addition to TBI. Fifteen days after irradiation, quantitative and spatial distribution of the hMSCs were studied. Histological analysis of mouse tissues confirmed the presence of radio-induced lesions in the irradiated fields. Following their infusion into nonirradiated animals, hMSCs homed at a very low level to various tissues (lung, bone marrow, and muscles) and no significant engraftment was found in other organs. TBI induced an increase of engraftment levels of hMSCs in the brain, heart, bone marrow, and muscles. Abdominal irradiation (AI) as compared with leg irradiation (LI) increased hMSC engraftment in the exposed area (the gut, liver, and spleen). Hind LI as compared with AI increased hMSC engraftment in the exposed area (skin, quadriceps, and muscles). An increase of hMSC engraftment in organs outside the fields of the ALI was also observed. Conversely, following LI, hMSC engraftment was increased in the brain as compared with AI. This study shows that engraftment of hMSCs in NOD/ SCID mice with significantly increased in response to tissue injuries following TBI with or without ALI. ALI induced an increase of the level of engraftment at sites outside the local irradiation

  9. Congenital radial and thumb aplasia in a neonatal owl monkey (Aotus nancymaae).

    PubMed

    Schuler, Anne Michele; Gibson, Susan V; Brady, Alan G; Abee, Christian R; Scammell, Jonathan G

    2007-09-01

    This report describes congenital radial and thumb aplasia in a neonatal owl monkey. Congenital limb deformities in human neonates and Old World primate species have been well characterized. The many probable causes of these congenital defects in skeletal structure include fetal exposure to environmental toxins and genetic influences. In nonhuman primates, the cause frequently remains undetermined. In the case we present, the neonate presented for examination because of inability to cling to the dam. The forelimbs were contracted distally, and thumbs were absent. Radiographs indicated complete radial aplasia and other skeletal abnormalities. This description is the fi rst case study of congenital radial and thumb aplasia in a New World primate species.

  10. Study of non-syndromic thumb aplasia in six independent cases

    PubMed Central

    Riaz, Hafiza Fizzah; Lal, Karmoon; Ahmad, Bashir; Shuaib, Muhammad; Naqvi, Syeda Farwa; Malik, Sajid

    2014-01-01

    Objectives: To report on six independent and isolated cases demonstrating thumb aplasia as an essentially limb-specific phenotype. Methods: The subjects were ascertained during 2011-2013 from six different geographic regions of Pakistan, and underwent detailed clinical and phenotypic examination. Results: The affected arms of patients had complete absence of first digital rays, medial inclinations of second and fifth fingers, narrowing of palms, missing carpals, and shortening of zeugopod. All the subjects were presented with isolated and sporadic limb deficiencies, and five had no family history of limb or any other malformation. Parental consanguinity was denied in majority of the cases. We present detailed phenotypic manifestation of thumb apalsia in these subjects. Conclusion: Thumb aplasia markedly impairs the normal function of affected hand. Surgical procedures like pollicisation of the index finger should be employed to improve the quality of life of these subjects. There is so far no specific genetic factor known for isolated thumb aplasia, compromising an accurate genetic counseling. Collection of patients with similar phenotypic presentations could be useful in further molecular genetic investigations. PMID:24949004

  11. Mitigation of lung injury after accidental exposure to radiation.

    PubMed

    Mahmood, J; Jelveh, S; Calveley, V; Zaidi, A; Doctrow, S R; Hill, R P

    2011-12-01

    There is a serious need to develop effective mitigators against accidental radiation exposures. In radiation accidents, many people may receive nonuniform whole-body or partial-body irradiation. The lung is one of the more radiosensitive organs, demonstrating pneumonitis and fibrosis that are believed to develop at least partially because of radiation-induced chronic inflammation. Here we addressed the crucial questions of how damage to the lung can be mitigated and whether the response is affected by irradiation to the rest of the body. We examined the widely used dietary supplement genistein given at two dietary levels (750 or 3750 mg/kg) to Fischer rats irradiated with 12 Gy to the lung or 8 Gy to the lung + 4 Gy to the whole body excluding the head and tail (whole torso). We found that genistein had promising mitigating effects on oxidative damage, pneumonitis and fibrosis even at late times (36 weeks) when drug treatment was initiated 1 week after irradiation and stopped at 28 weeks postirradiation. The higher dose of genistein showed no greater beneficial effect. Combined lung and whole-torso irradiation caused more lung-related severe morbidity resulting in euthanasia of the animals than lung irradiation alone.

  12. Genetics Home Reference: nonsyndromic aplasia cutis congenita

    MedlinePlus

    ... are some genetic conditions more common in particular ethnic groups? Genetic Changes Nonsyndromic aplasia cutis congenita can have different causes, and often the cause is unknown. Because the condition is sometimes found in multiple members of a family, it is thought to have a genetic component; ...

  13. Genetics Home Reference: Müllerian aplasia and hyperandrogenism

    MedlinePlus

    ... are some genetic conditions more common in particular ethnic groups? Genetic Changes Mutations in the WNT4 gene cause Müllerian aplasia and hyperandrogenism . This gene belongs to a family of WNT genes that play critical roles in ...

  14. Reconstruction of bilateral tibial aplasia and split hand-foot syndrome in a father and daughter.

    PubMed

    Al Kaissi, Ali; Ganger, Rudolf; Klaushofer, Klaus; Grill, Franz

    2014-01-01

    Tibial aplasia is of heterogeneous aetiology, the majority of reports are sporadic. We describe the reconstruction procedures in two subjects - a daughter and father manifested autosomal dominant (AD) inheritance of the bilateral tibial aplasia and split hand-foot syndrome. Reconstruction of these patients required multiple surgical procedures and orthoprosthesis was mandatory. The main goal of treatment was to achieve walking. Stabilization of the ankle joint by fibular-talar-chondrodesis on both sides, followed by bilateral Brown-procedure at the knee joint level has been applied accordingly. The outcome was with improved function of the deformed limbs and walking was achieved with simultaneous designation of orthotic fitting. This is the first study encompassing the diagnosis and management of a father and daughter with bilateral tibial aplasia associated with variable split hand/foot deformity without foot ablation. Our patients showed the typical AD pattern of inheritance of split-hand/foot and tibial aplasia.

  15. Aplasia of the mandibular condyle associated with some orthopaedic abnormalities

    PubMed Central

    Canger, E M; Çelenk, P

    2012-01-01

    A rare case of aplasia of mandibular condyle associated with some other orthopaedic problems is presented. A 5-year-old boy attended our clinic with a chief complaint of facial asymmetry and chewing difficulty. The mandible was deviated to the left. The occlusion also showed a deflection to the left of the mandibular midline. He also had walking difficulty owing to a hip abnormality. Panoramic radiographic examination of the patient revealed that the left mandibular condyl was totally absent. The right condyle was unremarkable. His history revealed neither trauma nor any significant disease. Aplasia is a rare anomaly and means the insufficient development of the mandibular condyle. True agnesis of the mandibular condyle is extremely rare. Association of the manifestations of the patient with some orthopaedic problems makes this case interesting. PMID:22116127

  16. [Risk factors for teeth aplasia and hypoplasia in cleft lip and palate children].

    PubMed

    Korolenkova, M V; Starikova, N V; Ageeva, L V

    2016-01-01

    The aim of the study was to assess the significance of environmental risk factors for teeth aplasia and hypoplasia in cleft lip and palate children. Two hundred and forty-seven cleft lip and palate (CLP) children were enrolled in the study including 105 (42.5%) with bilateral CLP and 57.5% with unilateral CLP. The mean age was 11.2±4.9 years. Teeth condition was assessed clinically and radiologically. The impact of risk factors for teeth anomalies was analyzed by retrospective data obtained from computer database (absence of preoperative orthopedic treatment, palatal defects after primary palatoplasty and type of primary procedures). Surgical trauma by early periosteoplasty (at the age of 3-4 months), excessive scarring and tissue traction due to absence of early orthopedic treatment and palatal defect were associated with significantly higher incidence of incisors hypoplasia (both developmental enamel defects and microdentia) and aplasia of central incisors not seen in the other study subgroups. Incisors aplasia and hypoplasia in CLP patients do not always have disembryogenic origin but may depend on external environmental factors, including surgical trauma.

  17. Holoprosencephaly and Pure Red Cell Aplasia in a Feline Leukaemia Virus-Positive Kitten.

    PubMed

    Southard, T L; Rodriguez-Ramos Fernandez, J; Priest, H; Stokol, T

    2016-01-01

    A 9-month-old, female, domestic longhair cat with severe anaemia tested positive for feline leukaemia virus (FeLV) and was humanely destroyed and submitted for necropsy examination. Gross findings included a non-divided rostral telencephalon, consistent with semilobar holoprosencephaly. Histological examination of the bone marrow revealed an almost complete absence of erythroid precursor cells, consistent with pure red cell aplasia, and mild to moderate myelofibrosis. This case demonstrates a very unusual central nervous system defect, as well as an atypical presentation of pure red cell aplasia, in a FeLV-positive kitten. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Segmental aplasia of the uterine horn in a cat.

    PubMed

    Marcella, K L; Ramirez, M; Hammerslag, K L

    1985-01-15

    A 4.5-year-old female domestic longhair cat with a history of intermittent abdominal distention following estrus and infertility was admitted for routine vaccinations. Radiographs revealed 2 large blunt-ended tubular structures overlapping each other in the abdomen. Segmental aplasia of the right uterine horn was diagnosed following exploratory laparotomy and ovariohysterectomy.

  19. Antibodies to recombinant human erythropoietin causing pure red cell aplasia.

    PubMed

    Prabhakar, S S; Muhlfelder, T

    1997-05-01

    Recombinant human erythropoietin (rHuEPO) is used extensively in anemic patients on dialysis and other patients and is regarded as very safe and effective in the management of anemia in these patients. To date, there is no report on the development of antibodies to rHuEPO in the patients treated with this drug. We report here a patient who developed antibodies to rHuEPO and as a result developed pure red cell aplasia. A 63-year-old black male with end-stage renal disease secondary to hypertension was placed on chronic dialytic therapy and tolerated rHuEPO treatment well for two years. A rapidly progressive anemia was then noted which was unresponsive to maximal doses of rHuEPO and the patient soon became transfusion-dependent. Bone marrow examination revealed paucity of red cell precursors. A detailed search for the cause of this pure red cell aplasia was unrevealing. Serological tests for Parvovirus B19 infection were negative. Antibodies for rHuEPO were tested by radioimmuno-precipitation assay and were found positive. In the course of several months, the antibody titer declined spontaneously to negligible levels with simultaneous improvement in the anemia and reappearance of red cell precursors in the bone marrow. This is the first patient to be reported who formed antibodies to rHuEPO and as a consequence developed pure red cell aplasia. Thus we conclude that although very rare, antibody production to rHuEPO should be considered in evaluating patients with EPO-resistant anemia with no obvious etiology.

  20. Unilateral Ankylosis of Temporomandibular Joint (TMJ) with Contralateral Condylar Aplasia and Related Orthopedic Deformity – Syndromic or Nonsyndromic?

    PubMed Central

    Vijay, Pradkhshana; Sunil, VSB; Bajpai, Manas; Chhibber, Neha

    2015-01-01

    Condylar aplasia which means “failure of development” is a rare condition and can be unilateral or bilateral. Mandibular condylar Aplasia without any association with syndrome is extremely rare. Temporomandibular joint (TMJ) ankylosis results from trauma, infection and inadequate surgical treatment of the condylar area. Congenital cases are very rare. We report case of congenital unilateral aplasia of left mandibular condyle with ankylosis of right condyle, with an associated orthopedic deformity in a nine-year-old male patient, which may be a part of some unreported syndrome that has not been mentioned so far in literature. As per our best knowledge, no other case including such clinical features has been reported. PMID:25738097

  1. Electron-beam irradiation-induced gate oxide degradation

    NASA Astrophysics Data System (ADS)

    Cho, Byung Jin; Chong, Pei Fen; Chor, Eng Fong; Joo, Moon Sig; Yeo, In Seok

    2000-12-01

    Gate oxide degradation induced by electron-beam irradiation has been studied. A large increase in the low-field excess leakage current was observed on irradiated oxides and this was very similar to electrical stress-induced leakage currents. Unlike conventional electrical stress-induced leakage currents, however, electron-beam induced leakage currents exhibit a power law relationship with fluency without any signs of saturation. It has also been found that the electron-beam neither accelerates nor initiates quasibreakdown of the ultrathin gate oxide. Therefore, the traps generated by electron-beam irradiation do not contribute to quasibreakdown, only to the leakage current.

  2. Linezolid Induced Twice Pure Red Cell Aplasia in a Patient with Central Nervous System Infection after Allogeneic Stem Cell Transplantation.

    PubMed

    Hu, Wenqing; Shi, Bing; Liu, Lihui; He, Shengke; Ye, Liping; Tian, DengMei; Zhang, Yongqing

    2016-01-01

    Linezolid (LZD), severed as the first oxazolidinone antibiotic, was active against multidrug-resistant gram-positive strains. LZD can induce thrombocytopenia, anemia and leukocytopenia. Currently, reports on pure red cell aplasia (PRCA) cases induced by LZD are relatively rare (4-7). In this paper, we reported a patient with PRCA twice induced by LZD. A 37-year-old man was diagnosed with myelodysplatic syndrome (MDS) and underwent allo-HSCT from an unrelated donor with ABO blood type and leukocyte antigen (HLA)-matching. After HSCT for 2 years, the patient suffered from refractory fever and headache. He was first treated with empirical antifungal agent and antibiotics for central nervous system (CNS) infection, but then changed to LZD therapy for little effect. Twenty-eight days after LZD treatment, the symptom improved significantly but the hemoglobin declined to 70 g/L and the reticulocyte level was only 0.23%. The LZD therapy was stopped and the fever and headache symptoms reoccurred 1 week latter. Then, erythropoietin (EPO) and halved dosage of LZD were used for treatment. The CNS infection and the anemia symptom relieved gradually and the level of hemoglobin and reticulocyte declined again. After blood transfusion, the half dose of LZD was sustained without anaemia recovery. In summary, patients with anemia, myelosuppressants history or potential abnormal proliferation of T cells may suffer PRCA with long term LZD treatment. The monitoring of complete blood count and reticulocyte count were necessary during LZD therapy. If the clinical condition permits, LZD dosage reduction and blood transfusion should be considered.

  3. [Aplasia of the posterior arch of the atlas--report on two cases].

    PubMed

    Nakamura, T; Kadoya, S; Itoh, S; Kwak, R; Suzuki, T; Satoh, S

    1987-02-01

    Two cases of aplasia of the posterior arch of the atlas incidentally found are reported. Case 1: A 37-year-old man hit the forehead and the right mandible against the front glass at a head-on collision of his car and was brought to the emergency room. He was alert and neurologically normal except for multiple incision wounds with glass fragments in the face. CT, and cervical X-rays revealed total absence of the posterior arch of the atlas. Case 2: A 73-year-old woman, who sustained whip lash injury at an automobile accident, was admitted several hours after injury, complaining of neck and occipital pain. No neurological deficit was seen. CT demonstrated hemi-aplasia of the posterior arch of the atlas and isolated rudimentary posterior tubercle. Review of the literature and discussions were made on the incidence and genesis of this anomaly.

  4. A Model for Precise and Uniform Pelvic- and Limb-Sparing Abdominal Irradiation to Study the Radiation-Induced Gastrointestinal Syndrome in Mice Using Small Animal Irradiation Systems.

    PubMed

    Brodin, N Patrik; Velcich, Anna; Guha, Chandan; Tomé, Wolfgang A

    2017-01-01

    Currently, no readily available mitigators exist for acute abdominal radiation injury. Here, we present an animal model for precise and homogenous limb-sparing abdominal irradiation (LSAIR) to study the radiation-induced gastrointestinal syndrome (RIGS). The LSAIR technique was developed using the small animal radiation research platform (SARRP) with image guidance capabilities. We delivered LSAIR at doses between 14 and 18 Gy on 8- to 10-week-old male C57BL/6 mice. Histological analysis was performed to confirm that the observed mortality was due to acute abdominal radiation injury. A steep dose-response relationship was found for survival, with no deaths seen at doses below 16 Gy and 100% mortality at above 17 Gy. All deaths occurred between 6 and 10 days after irradiation, consistent with the onset of RIGS. This was further confirmed by histological analysis showing clear differences in the number of regenerative intestinal crypts between animals receiving sublethal (14 Gy) and 100% lethal (18 Gy) radiation. The developed LSAIR technique provides uniform dose delivery with a clear dose response, consistent with acute abdominal radiation injury on histological examination. This model can provide a useful tool for researchers investigating the development of mitigators for accidental or clinical high-dose abdominal irradiation.

  5. Surgical treatment and optical coherence tomographic evaluation for accidental laser-induced full-thickness macular holes.

    PubMed

    Qi, Y; Wang, Y; You, Q; Tsai, F; Liu, W

    2017-07-01

    PurposeTo report OCT appearance and surgical outcomes of full-thickness macular holes (MHs) accidentally caused by laser devices.Patients and methodsThis retrospective case series included 11 eyes of 11 patients with laser-induced MHs treated by pars plana vitrectomy, internal limiting membrane (ILM) peeling, and gas or silicone oil tamponade. Evaluations included a full ophthalmic examination, macular spectral-domain optical coherence tomography (SD-OCT), and fundus photography. Main outcome measures is MH closure and final visual acuity; the secondary outcome was the changes of retinal pigment epithelium and photoreceptor layer evaluated by sequential post-operative SD-OCT images.ResultsFive patients were accidentally injured by a yttrium aluminum garnet (YAG) laser and six patients by handheld laser. MH diameters ranged from 272 to 815 μm (mean, 505.5±163.0 μm) preoperatively. Best-corrected visual acuity (BCVA) improved from a mean of 0.90 logMAR (range, counting finger-8/20) preoperatively to a mean of 0.34 logMAR (range, a counting finger-20/20) postoperatively (P=0.001, t=4.521). Seven of 11 patients (63.6%) achieved a BCVA better than 10/20. Ten patients had a subfoveal hyperreflectivity and four patients had a focal choroidal depression subfoveal preoperatively. At the last follow-up, all 11 eyes demonstrated the following: closure of the macular hole, variable degrees of disruption of external limiting membrane (ELM) and outer photoreceptor ellipsoid and interdigitation bands. In 10 eyes, the disruption was in the form of focal defects in the outer retina. After surgery, the subfoveal hyperreflectivity and focal choroidal depression remained.ConclusionAccidental laser-induced full-thickness macular holes can be successfully closed with surgery. Inadvertent retinal injury from laser devices, especially handheld laser injury has occurred with increasing frequency in recent years. However, there is a paucity of data regarding these types of injuries

  6. Focal brain lesions induced with ultraviolet irradiation.

    PubMed

    Nakata, Mariko; Nagasaka, Kazuaki; Shimoda, Masayuki; Takashima, Ichiro; Yamamoto, Shinya

    2018-05-22

    Lesion and inactivation methods have played important roles in neuroscience studies. However, traditional techniques for creating a brain lesion are highly invasive, and control of lesion size and shape using these techniques is not easy. Here, we developed a novel method for creating a lesion on the cortical surface via 365 nm ultraviolet (UV) irradiation without breaking the dura mater. We demonstrated that 2.0 mWh UV irradiation, but not the same amount of non-UV light irradiation, induced an inverted bell-shaped lesion with neuronal loss and accumulation of glial cells. Moreover, the volume of the UV irradiation-induced lesion depended on the UV light exposure amount. We further succeeded in visualizing the lesioned site in a living animal using magnetic resonance imaging (MRI). Importantly, we also observed using an optical imaging technique that the spread of neural activation evoked by adjacent cortical stimulation disappeared only at the UV-irradiated site. In summary, UV irradiation can induce a focal brain lesion with a stable shape and size in a less invasive manner than traditional lesioning methods. This method is applicable to not only neuroscientific lesion experiments but also studies of the focal brain injury recovery process.

  7. Metastatic angiosarcoma of the spleen after accidental radiation exposure: a case report.

    PubMed

    Geffen, D B; Zirkin, H J; Mermershtain, W; Cohen, Y; Ariad, S

    1998-04-01

    Angiosarcoma is a rare malignant tumor arising from endothelial cells of blood vessels or lymphatic channels. Therapeutic irradiation, thoriumdioxide administration, pyothorax, and polyvinyl chloride exposure have been shown to be predisposing factors for developing angiosarcoma. Accidental radiation exposure has not been associated with angiosarcoma. We present an unusual case of angiosarcoma of the spleen, with metastases to bone, liver, breast, and bone marrow, in a woman who lived near the Chernobyl nuclear facility in the former Soviet Union at the time of the reactor accident in 1986. To the best of our knowledge, this is the first report of metastatic angiosarcoma after accidental radiation exposure.

  8. 48XXYY Syndrome in an Adult with Type 2 Diabetes Mellitus, Unilateral Renal Aplasia, and Pigmentary Retinitis.

    PubMed

    Zantour, Baha; Sfar, Mohamed Habib; Younes, Samia; Alaya, Wafa; Kamoun, Mahdi; Mkaouar, Emna; Jerbi, Saida

    2010-01-01

    A 45-year-old male was referred for diabetes mellitus. Clinical examination found a family history of multiple precocious deaths, strong consanguinity, personal history of seizures during childhood, small testicles, small penis, sparse body hair, long arms and legs, dysmorphic features, mental retardation, dysarthria, tremor, and mild gait ataxia. Investigations found pigmentary retinitis, metabolic syndrome, unilateral renal aplasia, and hypergonadotropic hypogonadism, and ruled out mitochondrial cytopathy and leucodystrophy. Karyotype study showed a 48XXYY chromosomal type. Renal aplasia and pigmentary retinitis have not been described in 48XXYY patients. They may be related to the chromosomal sex aneuploidy, or caused by other genetic aberrations in light of the high consanguinity rate in the patient's family.

  9. 48XXYY Syndrome in an Adult with Type 2 Diabetes Mellitus, Unilateral Renal Aplasia, and Pigmentary Retinitis

    PubMed Central

    Zantour, Baha; Sfar, Mohamed Habib; Younes, Samia; Alaya, Wafa; Kamoun, Mahdi; Mkaouar, Emna; Jerbi, Saida

    2010-01-01

    A 45-year-old male was referred for diabetes mellitus. Clinical examination found a family history of multiple precocious deaths, strong consanguinity, personal history of seizures during childhood, small testicles, small penis, sparse body hair, long arms and legs, dysmorphic features, mental retardation, dysarthria, tremor, and mild gait ataxia. Investigations found pigmentary retinitis, metabolic syndrome, unilateral renal aplasia, and hypergonadotropic hypogonadism, and ruled out mitochondrial cytopathy and leucodystrophy. Karyotype study showed a 48XXYY chromosomal type. Renal aplasia and pigmentary retinitis have not been described in 48XXYY patients. They may be related to the chromosomal sex aneuploidy, or caused by other genetic aberrations in light of the high consanguinity rate in the patient's family. PMID:20827436

  10. Accidental Predissociation: A Special Case of Photo-Induced Isotope Fractionation Effect and Possible Occurrence in Nature

    NASA Astrophysics Data System (ADS)

    Chakraborty, S.; Thiemens, M. H.

    2009-12-01

    Photo-Induced Isotope Fractionation Effects (PHIFE) are known to produce isotopic frac-tionation in some photo-dissociating molecules (1-2). The PHIFE formalism is based on the Born-Oppenheimer approximation and the Reflection Principle. The isotopic fractionation arises principally from the spectral shift induced by the small difference in zero point energy between isotopologues and the contraction of the wave function due to isotopic substitution, consequently, the associated isotopic fractionations depends on the reduced mass of the isotopically substi-tuted species. The PHIFE formalism is only applicable to the molecules which undergo direct photo-dissociation that possess continuous absorption spectra. Simple molecules (N2, O2, CO) however do not follow a direct dissociation pathway and dissociate through an indirect process termed predissociation, which occurs when the molecule is excited to a quasi-bound state energetically above the dissociation continuum. The PHIFE formalism is not applicable when the absorption spectra are discrete. The assumption that the lightest isotopologues are preferentially predissociated is only valid for restricted predissociation cases. There is a special case of predissociation known as ‘accidental predissociation’ (3), which takes place through an intermediate bound state in two steps (i) leakage to an intermediate bound state (coupled through spin orbit interaction) and, (ii) predissociation to a third quasi-bound state from the intermediate state. Line broadening at an accidental predissociation is a function of the magnitude of coupling matrix elements and the linewidths are strongly influenced by isotopic substitution (4). An anomalous isotopic effect in accidental predissociation was spectroscopically observed in CO (5), N2 (4) and BeH (6). We measured the isotopic fractionation for the first time in two accidental predissociating states of CO through VUV photodissociation using the 9.0.2 beamline at ALS (7-8). In

  11. Polymer Morphological Change Induced by Terahertz Irradiation

    PubMed Central

    Hoshina, Hiromichi; Suzuki, Hal; Otani, Chiko; Nagai, Masaya; Kawase, Keigo; Irizawa, Akinori; Isoyama, Goro

    2016-01-01

    As terahertz (THz) frequencies correspond to those of the intermolecular vibrational modes in a polymer, intense THz wave irradiation affects the macromolecular polymorph, which determines the polymer properties and functions. THz photon energy is quite low compared to the covalent bond energy; therefore, conformational changes can be induced “softly,” without damaging the chemical structures. Here, we irradiate a poly(3-hydroxybutylate) (PHB) / chloroform solution during solvent casting crystallization using a THz wave generated by a free electron laser (FEL). Morphological observation shows the formation of micrometer-sized crystals in response to the THz wave irradiation. Further, a 10−20% increase in crystallinity is observed through analysis of the infrared (IR) absorption spectra. The peak power density of the irradiating THz wave is 40 MW/cm2, which is significantly lower than the typical laser intensities used for material manipulation. We demonstrate for the first time that the THz wave effectively induces the intermolecular rearrangement of polymer macromolecules. PMID:27272984

  12. Polymer Morphological Change Induced by Terahertz Irradiation

    NASA Astrophysics Data System (ADS)

    Hoshina, Hiromichi; Suzuki, Hal; Otani, Chiko; Nagai, Masaya; Kawase, Keigo; Irizawa, Akinori; Isoyama, Goro

    2016-06-01

    As terahertz (THz) frequencies correspond to those of the intermolecular vibrational modes in a polymer, intense THz wave irradiation affects the macromolecular polymorph, which determines the polymer properties and functions. THz photon energy is quite low compared to the covalent bond energy; therefore, conformational changes can be induced “softly,” without damaging the chemical structures. Here, we irradiate a poly(3-hydroxybutylate) (PHB) / chloroform solution during solvent casting crystallization using a THz wave generated by a free electron laser (FEL). Morphological observation shows the formation of micrometer-sized crystals in response to the THz wave irradiation. Further, a 10-20% increase in crystallinity is observed through analysis of the infrared (IR) absorption spectra. The peak power density of the irradiating THz wave is 40 MW/cm2, which is significantly lower than the typical laser intensities used for material manipulation. We demonstrate for the first time that the THz wave effectively induces the intermolecular rearrangement of polymer macromolecules.

  13. Irradiation-induced phenomena in carbon nanomaterials

    NASA Astrophysics Data System (ADS)

    Krasheninnikov, Arkady

    2008-03-01

    The irradiation of solids with energetic particles such as electrons or ions is associated with disorder, normally an undesirable phenomenon. However, recent experiments [for an overview, see A.V Krasheninnikov, F. Banhart, Nature Materials, 6 (2007) 723] on bombardment of carbon nanostructures with energetic particles demonstrate that irradiation can have beneficial effects and that electron or ion beams may serve as tools to change the morphology and tailor mechanical, electronic and even magnetic properties of nanostructured carbon systems. We systematically study irradiation effects in carbon nanotubes and other forms of nano-structured carbon experimentally and theoretically by employing various atomistic models ranging from empirical potentials to time-dependent density functional theory. In my presentation, I will briefly review the recent progress in our understanding of ion-irradiation-induced phenomena in nano-structured carbon and present our recent theoretical [A.V Krasheninnikov, et al., Phys. Rev. Lett., 99 (2007) 016104, A. Tolvanen et al, Appl. Phys. Lett. 91 (2007) 173109.] and experimental [O. Lehtinen et al., to be published] results. I dwell on the ``beneficial'' role of defects and impurities in nanotubes and related systems. Finally, I will present the results of simulations of irradiation-induced pressure build-up inside nanotubes encapsulated with metals [L. Sun, et al., Science 312 (2006) 1199]. Electron irradiation of such composite systems in the transmission electron microscope gives rise to contraction of nanotube shells and thus to high pressure. The irradiation-stimulated pressure can be as high as 40 GPa, which makes it possible to study phase transformations at the nanoscale with high spatial resolution. I will also address the mechanisms of plastic deformation of small metal particles inside carbon shells at high temperatures, which may be important for understanding catalytic growth of carbon nanotubes.

  14. Nitric oxide-mediated bystander signal transduction induced by heavy-ion microbeam irradiation

    NASA Astrophysics Data System (ADS)

    Tomita, Masanori; Matsumoto, Hideki; Funayama, Tomoo; Yokota, Yuichiro; Otsuka, Kensuke; Maeda, Munetoshi; Kobayashi, Yasuhiko

    2015-07-01

    In general, a radiation-induced bystander response is known to be a cellular response induced in non-irradiated cells after receiving bystander signaling factors released from directly irradiated cells within a cell population. Bystander responses induced by high-linear energy transfer (LET) heavy ions at low fluence are an important health problem for astronauts in space. Bystander responses are mediated via physical cell-cell contact, such as gap-junction intercellular communication (GJIC) and/or diffusive factors released into the medium in cell culture conditions. Nitric oxide (NO) is a well-known major initiator/mediator of intercellular signaling within culture medium during bystander responses. In this study, we investigated the NO-mediated bystander signal transduction induced by high-LET argon (Ar)-ion microbeam irradiation of normal human fibroblasts. Foci formation by DNA double-strand break repair proteins was induced in non-irradiated cells, which were co-cultured with those irradiated by high-LET Ar-ion microbeams in the same culture plate. Foci formation was suppressed significantly by pretreatment with an NO scavenger. Furthermore, NO-mediated reproductive cell death was also induced in bystander cells. Phosphorylation of NF-κB and Akt were induced during NO-mediated bystander signaling in the irradiated and bystander cells. However, the activation of these proteins depended on the incubation time after irradiation. The accumulation of cyclooxygenase-2 (COX-2), a downstream target of NO and NF-κB, was observed in the bystander cells 6 h after irradiation but not in the directly irradiated cells. Our findings suggest that Akt- and NF-κB-dependent signaling pathways involving COX-2 play important roles in NO-mediated high-LET heavy-ion-induced bystander responses. In addition, COX-2 may be used as a molecular marker of high-LET heavy-ion-induced bystander cells to distinguish them from directly irradiated cells, although this may depend on the time

  15. Irradiation Induced Microstructure Evolution in Nanostructured Materials: A Review

    PubMed Central

    Liu, Wenbo; Ji, Yanzhou; Tan, Pengkang; Zang, Hang; He, Chaohui; Yun, Di; Zhang, Chi; Yang, Zhigang

    2016-01-01

    Nanostructured (NS) materials may have different irradiation resistance from their coarse-grained (CG) counterparts. In this review, we focus on the effect of grain boundaries (GBs)/interfaces on irradiation induced microstructure evolution and the irradiation tolerance of NS materials under irradiation. The features of void denuded zones (VDZs) and the unusual behavior of void formation near GBs/interfaces in metals due to the interactions between GBs/interfaces and irradiation-produced point defects are systematically reviewed. Some experimental results and calculation results show that NS materials have enhanced irradiation resistance, due to their extremely small grain sizes and large volume fractions of GBs/interfaces, which could absorb and annihilate the mobile defects produced during irradiation. However, there is also literature reporting reduced irradiation resistance or even amorphization of NS materials at a lower irradiation dose compared with their bulk counterparts, since the GBs are also characterized by excess energy (compared to that of single crystal materials) which could provide a shift in the total free energy that will lead to the amorphization process. The competition of these two effects leads to the different irradiation tolerance of NS materials. The irradiation-induced grain growth is dominated by irradiation temperature, dose, ion flux, character of GBs/interface and nanoprecipitates, although the decrease of grain sizes under irradiation is also observed in some experiments. PMID:28787902

  16. Ion-irradiation-induced damage of steels characterized by means of nanoindentation

    NASA Astrophysics Data System (ADS)

    Heintze, C.; Recknagel, C.; Bergner, F.; Hernández-Mayoral, M.; Kolitsch, A.

    2009-05-01

    Self-ion irradiation was used to simulate the damage caused by fast neutrons in the austenitic stainless steel SS 304 SA, the ferritic/martensitic steel Eurofer'97 and a Fe-9 at.%Cr model alloy. The irradiation-induced hardness change in the damage layer was evaluated by means of nanoindentation. Three-step irradiations were performed at room temperature and 300 °C up to 1 and 10 dpa. An irradiation-induced hardness change was shown for all materials. No influence of irradiation temperature could be resolved. Irradiation-induced hardening exhibits different fluence dependencies in Eurofer'97 and Fe-9 at.%Cr. While the data indicate a saturation-like behaviour for Fe-9 at.%Cr, an increase of hardness with fluence up to 10 dpa was found for Eurofer'97.

  17. Uterovaginal Anastomosis for Cases of Cryptomenorrhea Due to Cervical Atresia with Vaginal Aplasia: Benefits and Risks.

    PubMed

    Zayed, M; Fouad, R; Elsetohy, K A; Hashem, A T; AbdAllah, A A; Fathi, A I

    2017-12-01

    The objective of this study was to assess short-term benefits and risks of utero-vaginal anastomosis done for cases of cryptomenorrhea due to cervical atresia with vaginal aplasia. Prospective study. Surgical procedures were done between December 2013 and September 2015 at the department of Obstetrics and Gynecology, Cairo University Hospital. Five patients who had cryptomenorrhea due to cervical atresia associated with vaginal aplasia were included. Utero-vaginal anastomoses were performed in 2 stages; a stage of McIndoe vaginoplasty and a stage of excision of the atretic cervical tissue and anastomosing the uterus to the neovagina. Follow-up was done by gynecological and ultrasound examination in a duration ranged from 12 to 36 months. Occurrence of regular menstrual flow and relief of the severe cyclic pain. All patients had relief of the severe cyclic pain. Four patients had regular menstrual flow. One patient developed occlusion of the track after 1 year and needed dilatation once. Three patients developed low vaginal stenosis without occlusion of the track. One patient had rectal injury repaired without causing postoperative morbidity. Uterovaginal anastomosis is a promising conservative management option for cervical atresia with vaginal aplasia, which has benefits but is not free of risks. Long-term follow-up is still needed to judge its feasibility. We recommend performing McIndoe vaginoplasty as a starting stage before the anastomosis preferably in a separate setting. Copyright © 2017 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  18. Social evaluation of intentional, truly accidental, and negligently accidental helpers and harmers by 10-month-old infants.

    PubMed

    Woo, Brandon M; Steckler, Conor M; Le, Doan T; Hamlin, J Kiley

    2017-11-01

    Whereas adults largely base their evaluations of others' actions on others' intentions, a host of research in developmental psychology suggests that younger children privilege outcome over intention, leading them to condemn accidental harm. To date, this question has been examined only with children capable of language production. In the current studies, we utilized a non-linguistic puppet show paradigm to examine the evaluation of intentional and accidental acts of helping or harming in 10-month-old infants. In Experiment 1 (n=64), infants preferred intentional over accidental helpers but accidental over intentional harmers, suggestive that by this age infants incorporate information about others' intentions into their social evaluations. In Experiment 2 (n=64), infants did not distinguish "negligently" accidental from intentional helpers or harmers, suggestive that infants may find negligent accidents somewhat intentional. In Experiment 3 (n=64), we found that infants preferred truly accidental over negligently accidental harmers, but did not reliably distinguish negligently accidental from truly accidental helpers, consistent with past work with adults and children suggestive that humans are particularly sensitive to negligently accidental harm. Together, these results imply that infants engage in intention-based social evaluation of those who help and harm accidentally, so long as those accidents do not stem from negligence. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Berberine potentizes apoptosis induced by X-rays irradiation probably through modulation of gap junctions.

    PubMed

    Liu, Bing; Wang, Qin; Yuan, Dong-dong; Hong, Xiao-ting; Tao, Liang

    2011-04-01

    Clinical combination of some traditional Chinese medical herbs, including berberine, with irradiation is demonstrated to improve efficacy of tumor radiotherapy, yet the mechanisms for such effect remain largely unknown. The present study investigated the effect of berberine on apoptosis induced by X-rays irradiation and the relation between this effect and gap junction intercellular communication (GJIC). The role of gap junctions in the modulation of X-rays irradiation-induced apoptosis was explored by manipulation of connexin (Cx) expression, and gap junction function, using oleamide, a GJIC inhibitor, and berberine. In transfected HeLa cells, Cx32 expression increased apoptosis induced by X-rays irradiation, while inhibition of gap junction by oleamide reduced the irradiation responses, indicating the dependence of X-rays irradiation-induced apoptosis on GJIC. Berberine, at the concentrations without cytotoxicity, enhanced apoptosis induced by irradiation only in the presence of functional gap junctions. These results suggest that berberine potentizes cell apoptosis induced by X-rays irradiation, probably through enhancement of gap junction activity.

  20. Effect of proton irradiation on superconductivity in optimally doped BaFe 2 ( As 1 - x P x ) 2 single crystals

    DOE PAGES

    Smylie, M. P.; Leroux, M.; Mishra, V.; ...

    2016-03-10

    In this paper, irradiation with 4 MeV protons was used to systematically introduce defects in single crystals of the iron-arsenide superconductor BaFe 2(As 1-xP x) 2, x = 0.33. The effect of disorder on the low-temperature behavior of the London penetration depth λ(T) and transition temperature T c was investigated. In nearly optimally doped samples with T c ~ 29 K, signatures of a superconducting gap with nodes were observed. Contrary to previous reports on electron-irradiated crystals, we do not see a disorder-driven lifting of accidental nodes, and we observe that proton-induced defects are weaker pair breakers than electron-induced defects.more » Finally, we attribute our findings to anisotropic electron scattering caused by proton irradiation defects.« less

  1. Pure Red Cell Aplasia due to B19 Parvovirus Infection after Autologous Stem Cell Transplantation

    PubMed Central

    Tsirigotis, Panagiotis; Girkas, Konstantinos; Economopoulou, Christina; Bouchla, Anthoula; Papanicolaou, Nikolaos; Economopoulou, Panagiota; Papageorgiou, Sotirios; Pappa, Vassiliki; Dervenoulas, John

    2011-01-01

    Parvovirus B19 is recognized as a rare cause of pure red cell aplasia (PRCA) in allogeneic stem cell (SCT) and solid organ transplant patients. We report a patient with Hodgkin's disease who developed PRCA due to parvovirus B19 after autologous SCT and who had an excellent response after treatment with gamma-globulin. PMID:23198254

  2. Anti-inflammatory effect of selenium nanoparticles on the inflammation induced in irradiated rats.

    PubMed

    El-Ghazaly, M A; Fadel, N; Rashed, E; El-Batal, A; Kenawy, S A

    2017-02-01

    Selenium (Se) has been reported to possess anti-inflammatory properties, but its bioavailability and toxicity are considerable limiting factors. The present study aimed to investigate the possible anti-inflammatory and analgesic effects of selenium nanoparticles (Nano-Se) on inflammation induced in irradiated rats. Paw volume and nociceptive threshold were measured in carrageenan-induced paw edema and hyperalgesia model. Leukocytic count, tumor necrosis factor-α (TNF-α), prostaglandin E 2 (PGE 2 ), thiobarbituric acid reactive substances (TBAR), and total nitrate/nitrite (NOx) were estimated in the exudate collected from 6 day old air pouch model. Irradiated rats were exposed to 6 Gy gamma (γ)-irradiation. Nano-Se were administered orally in a dose of 2.55 mg/kg once before carrageenan injection in the first model and twice in the second model. The paw volume but not the nociceptive response produced by carrageenan in irradiated rats was higher than that induced in non-irradiated rats. Nano-Se were effective in reducing the paw volume in non-irradiated and irradiated rats but it did not alter the nociceptive threshold. The inflammation induced in irradiated rats increased all the estimated parameters in the exudate whereas; Nano-Se decreased their elevation in non-irradiated and irradiated rats. Nano-Se possess a potential anti-inflammatory activity on inflammation induced in irradiated rats.

  3. Study on elucidation of bactericidal effects induced by laser beam irradiation Measurement of dynamic stress on laser irradiated surface

    NASA Astrophysics Data System (ADS)

    Furumoto, Tatsuaki; Kasai, Atsushi; Tachiya, Hiroshi; Hosokawa, Akira; Ueda, Takashi

    2010-09-01

    In dental treatment, many types of laser beams have been used for various surgical treatments, and the influences of laser beam irradiation on bactericidal effect have been investigated. However, most of the work has been performed by irradiating to an agar plate with the colony of bacteria, and very few studies have been reported on the physical mechanism of bactericidal effects induced by laser beam irradiation. This paper deals with the measurement of dynamic stress induced in extracted human enamel by irradiation with Nd:YAG laser beams. Laser beams can be delivered to the enamel surface through a quartz optical fiber. Dynamic stress induced in the specimen using elastic wave propagation in a cylindrical long bar made of aluminum alloy is measured. Laser induced stress intensity is evaluated from dynamic strain measured by small semiconductor strain gauges. Carbon powder and titanium dioxide powder were applied to the human enamel surface as absorbents. Additionally, the phenomenon of laser beam irradiation to the human enamel surface was observed with an ultrahigh speed video camera. Results showed that a plasma was generated on the enamel surface during laser beam irradiation, and the melted tissues were scattered in the vertical direction against the enamel surface with a mushroom-like wave. Averaged scattering velocity of the melted tissues was 25.2 m/s. Induced dynamic stress on the enamel surface increased with increasing laser energy in each absorbent. Induced dynamic stresses with titanium dioxide powder were superior to those with carbon powder. Induced dynamic stress was related to volume of prepared cavity, and induced stress for the removal of unit volume of human enamel was 0.03 Pa/mm 3.

  4. [Aplasia cutis congenita associated with epidermolysis bullosa].

    PubMed

    Muñoz-Guerrero, Félix; Muñoz-Solís, Adrián Antonio; Ornelas-Aguirre, José Manuel

    2017-12-01

    Aplasia cutis congenita (ACC) is a skin condition of rare presentation, this disease is characterized by absence of skin at birth and associated with facial, skin and bone skull deformities. The diagnosis is mainly clinical. Male 5 days after birth, unique product of primigravida mother and no family history of relevance. Physical examination revealed bilateral and symmetrical skin defects of both lower extremities, the disease is characterized by skin fragility, scabs, and coated pseudomembrane ulcers, decreased interdigital space between toes of the left foot, retraction of the foot and genu varum. It was handled with allograft of epidermis cultured in vitro, general wound care and clinical follow-up. ACC associated with epidermolysis bullosa is one of the rarer forms of presentation. It is necessary to rule out other skin diseases. Clinical management is recommended with biological or synthetic skin cover, infection prevention, early treatment of complications and clinical follow. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  5. Like Father, Like Daughter-inherited cutis aplasia occurring in a family with Marfan syndrome: a case report.

    PubMed

    Islam, Yasmin Florence Khodeja; Williams, Charles A; Schoch, Jennifer Jane; Andrews, Israel David

    2017-01-01

    We present the case of a newborn with co-occurrence of Marfan syndrome and aplasia cutis congenita (ACC) and a family history significant for Marfan syndrome and ACC in the father. This case details a previously unreported mutation in Marfan syndrome and describes a novel coinheritance of Marfan syndrome and ACC.

  6. Accidental sodium hypochlorite-induced skin injury during endodontic treatment.

    PubMed

    Serper, Ahmet; Ozbek, Murat; Calt, Semra

    2004-03-01

    A case of accidental skin injury caused by leakage of sodium hypochlorite solution from the rubber dam during root canal preparation is reported. After placement of a rubber dam and initiation of root canal treatment, the patient complained of a burning sensation with sodium hypochlorite irrigation. The complaints were ignored by the practitioner, and a skin rash developed on and around the patient's chin, followed by scab formation. The patient required medical treatment with topical Hamamelis virginiana extract for 2 weeks, with full recovery.

  7. DNA Double-strand Breaks Induced byFractionated Neutron Beam Irradiation for Boron Neutron Capture Therapy.

    PubMed

    Kinashi, Yuko; Yokomizo, Natsuya; Takahashi, Sentaro

    2017-04-01

    To use the 53BP1 foci assay to detect DNA double-strand breaks induced by fractionated neutron beam irradiation of normal cells. The Kyoto University Research Reactor heavy-water facility and gamma-ray irradiation system were used as experimental radiation sources. After fixation of Chinese Hamster Ovary cells with 3.6% formalin, immunofluorescence staining was performed. Number and size of foci were analyzed using ImageJ software. Fractionated neutron irradiation induced 25% fewer 53BP1 foci than single irradiation at the same dose. By contrast, gamma irradiation induced 30% fewer 53BP1 foci than single irradiation at the same dose. Fractionated neutron irradiation induced larger foci than gamma irradiation, raising the possibility that persistent unrepaired DNA damage was amplified due to the high linear energy transfer component in the neutron beam. Unrepaired cluster DNA damage was more prevalent after fractionated neutron irradiation than after gamma irradiation. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  8. Electron-irradiation-induced crystallization at metallic amorphous/silicon oxide interfaces caused by electronic excitation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nagase, Takeshi, E-mail: t-nagase@uhvem.osaka-u.ac.jp; Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka 565-0871; Yamashita, Ryo

    2016-04-28

    Irradiation-induced crystallization of an amorphous phase was stimulated at a Pd-Si amorphous/silicon oxide (a(Pd-Si)/SiO{sub x}) interface at 298 K by electron irradiation at acceleration voltages ranging between 25 kV and 200 kV. Under irradiation, a Pd-Si amorphous phase was initially formed at the crystalline face-centered cubic palladium/silicon oxide (Pd/SiO{sub x}) interface, followed by the formation of a Pd{sub 2}Si intermetallic compound through irradiation-induced crystallization. The irradiation-induced crystallization can be considered to be stimulated not by defect introduction through the electron knock-on effects and electron-beam heating, but by the electronic excitation mechanism. The observed irradiation-induced structural change at the a(Pd-Si)/SiO{sub x} and Pd/SiO{sub x}more » interfaces indicates multiple structural modifications at the metal/silicon oxide interfaces through electronic excitation induced by the electron-beam processes.« less

  9. Enthalpy Landscape Dictates the Irradiation-Induced Disordering of Quartz

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krishnan, N. M. Anoop; Wang, Bu; Yu, Yingtian

    Here, under irradiation, minerals tend to experience an accumulation of structural defects, ultimately leading to a disordered atomic network. Despite the critical importance of understanding and predicting irradiation-induced damage, the physical origin of the initiation and saturation of defects remains poorly understood. Here, based on molecular dynamics simulations of α-quartz, we show that the topography of the enthalpy landscape governs irradiation-induced disordering. Specifically, we show that such disordering differs from that observed upon vitrification in that, prior to saturation, irradiated quartz accesses forbidden regions of the enthalpy landscape, i.e., those that are inaccessible by simply heating and cooling. Furthermore, wemore » demonstrate that damage saturates when the system accesses a local region of the enthalpy landscape corresponding to the configuration of an allowable liquid. At this stage, a sudden decrease in the heights of the energy barriers enhances relaxation, thereby preventing any further accumulation of defects and resulting in a defect-saturated disordered state.« less

  10. Enthalpy Landscape Dictates the Irradiation-Induced Disordering of Quartz

    DOE PAGES

    Krishnan, N. M. Anoop; Wang, Bu; Yu, Yingtian; ...

    2017-07-28

    Here, under irradiation, minerals tend to experience an accumulation of structural defects, ultimately leading to a disordered atomic network. Despite the critical importance of understanding and predicting irradiation-induced damage, the physical origin of the initiation and saturation of defects remains poorly understood. Here, based on molecular dynamics simulations of α-quartz, we show that the topography of the enthalpy landscape governs irradiation-induced disordering. Specifically, we show that such disordering differs from that observed upon vitrification in that, prior to saturation, irradiated quartz accesses forbidden regions of the enthalpy landscape, i.e., those that are inaccessible by simply heating and cooling. Furthermore, wemore » demonstrate that damage saturates when the system accesses a local region of the enthalpy landscape corresponding to the configuration of an allowable liquid. At this stage, a sudden decrease in the heights of the energy barriers enhances relaxation, thereby preventing any further accumulation of defects and resulting in a defect-saturated disordered state.« less

  11. Edaravone protects human peripheral blood lymphocytes from γ-irradiation-induced apoptosis and DNA damage.

    PubMed

    Chen, Liming; Liu, Yinghui; Dong, Liangliang; Chu, Xiaoxia

    2015-03-01

    Radiation-induced cellular injury is attributed primarily to the harmful effects of free radicals, which play a key role in irradiation-induced apoptosis. In this study, we investigated the radioprotective efficacy of edaravone, a licensed clinical drug and a powerful free radical scavenger that has been tested against γ-irradiation-induced cellular damage in cultured human peripheral blood lymphocytes in studies of various diseases. Edaravone was pre-incubated with lymphocytes for 2 h prior to γ-irradiation. It was found that pretreatment with edaravone increased cell viability and inhibited generation of γ-radiation-induced reactive oxygen species (ROS) in lymphocytes exposed to 3 Gy γ-radiation. In addition, γ-radiation decreased antioxidant enzymatic activity, such as superoxide dismutase and glutathione peroxidase, as well as the level of reduced glutathione. Conversely, treatment with 100 μM edaravone prior to irradiation improved antioxidant enzyme activity and increased reduced glutathione levels in irradiated lymphocytes. Importantly, we also report that edaravone reduced γ-irradiation-induced apoptosis through downregulation of Bax, upregulation of Bcl-2, and consequent reduction of the Bax:Bcl-2 ratio. The current study shows edaravone to be an effective radioprotector against γ-irradiation-induced cellular damage in lymphocytes in vitro. Finally, edaravone pretreatment significantly reduced DNA damage in γ-irradiated lymphocytes, as measured by comet assay (% tail DNA, tail length, tail moment, and olive tail moment) (p < 0.05). Thus, the current study indicates that edaravone offers protection from radiation-induced cytogenetic alterations.

  12. Radiation-induced segregation and precipitation behaviours around cascade clusters under electron irradiation.

    PubMed

    Sueishi, Yuichiro; Sakaguchi, Norihito; Shibayama, Tamaki; Kinoshita, Hiroshi; Takahashi, Heishichiro

    2003-01-01

    We have investigated the formation of cascade clusters and structural changes in them by means of electron irradiation following ion irradiation in an austenitic stainless steel. Almost all of the cascade clusters, which were introduced by the ion irradiation, grew to form interstitial-type dislocation loops or vacancy-type stacking fault tetrahedra after electron irradiation at 623 K, whereas a few of the dot-type clusters remained in the matrix. It was possible to recognize the concentration of Ni and Si by radiation-induced segregation around the dot-type clusters. After electron irradiation at 773 K, we found that some cascade clusters became precipitates (delta-Ni2Si) due to radiation-induced precipitation. This suggests that the cascade clusters could directly become precipitation sites during irradiation.

  13. Studies on Red Cell Aplasia. V. PRESENCE OF ERYTHROBLAST CYTOTOXICITY IN γG-GLOBULIN FRACTION OF PLASMA

    PubMed Central

    Krantz, Sanford B.; Moore, W. H.; Zaentz, S. Donald

    1973-01-01

    The marrow cells of a patient with pure red cell aplasia markedly increased their rate of heme synthesis when they were freed from the host environment and were incubated in vitro. When the red cell aplasia was treated with cyclophosphamide and prednisone, marrow cell incorporation of 59Fe into heme in vitro increased several weeks before a reticulocytosis was apparent, and was the earliest effect noted. The plasma γG-globulins of this patient inhibited heme synthesis by normal marrow cells or the patient's own marrow cells obtained after remission of the disease. Since the inhibition of heme synthesis could be the result of damage to erythroblasts, the patient's posttreatment marrow cells or normal marrow cells were labeled with 59Fe and were then incubated with the patient's pretreatment, treatment, and posttreatment γG-globulins as well as normal γG-globulins. At the end of this incubation the supernatant and cells were separated and counted. Heme was extracted and also was counted. Treatment of the cells with the patient's pretreatment γG-globulins resulted in a release of 40% of the radioactive heme from the cells. This represented the loss of radioactive hemoglobin and was an index of erythroblast cytotoxicity. A progressive disappearance of the cytotoxic factor in the γG-globulins occurred in the 3 wk period preceding the onset of reticulocytes in the patient's blood. Posttreatment and normal γG-globulins did not produce this effect and increased injury of red cells and lymphocytes was not produced by the patient's pretreatment γG-globulins. These studies demonstrate a method for measuring erythroblast cytoxicity and show that red cell aplasia is associated with γG-globulins that specifically damage erythroblasts. Whether interference with new erythroblast development also occurs and contributes to the inhibition of heme synthesis has not yet been ascertained. Images PMID:4119161

  14. Radiation-Induced Epigenetic Alterations after Low and High LET Irradiations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aypar, Umut; Morgan, William F.; Baulch, Janet E.

    Epigenetics, including DNA methylation and microRNA (miRNA) expression, could be the missing link in understanding the delayed, non-targeted effects of radiation including radiationinduced genomic instability (RIGI). This study tests the hypothesis that irradiation induces epigenetic aberrations, which could eventually lead to RIGI, and that the epigenetic aberrations induced by low linear energy transfer (LET) irradiation are different than those induced by high LET irradiations. GM10115 cells were irradiated with low LET x-rays and high LET iron (Fe) ions and evaluated for DNA damage, cell survival and chromosomal instability. The cells were also evaluated for specific locus methylation of nuclear factor-kappamore » B (NFκB), tumor suppressor in lung cancer 1 (TSLC1) and cadherin 1 (CDH1) gene promoter regions, long interspersed nuclear element 1 (LINE-1) and Alu repeat element methylation, CpG and non-CpG global methylation and miRNA expression levels. Irradiated cells showed increased micronucleus induction and cell killing immediately following exposure, but were chromosomally stable at delayed times post-irradiation. At this same delayed time, alterations in repeat element and global DNA methylation and miRNA expression were observed. Analyses of DNA methylation predominantly showed hypomethylation, however hypermethylation was also observed. MiRNA shown to be altered in expression level after x-ray irradiation are involved in chromatin remodeling and DNA methylation. Different and higher incidence of epigenetic changes were observed after exposure to low LET x-rays than high LET Fe ions even though Fe ions elicited more chromosomal damage and cell killing. This study also shows that the irradiated cells acquire epigenetic changes even though they are chromosomally stable suggesting that epigenetic aberrations may arise in the cell without initiating RIGI.« less

  15. Characterization of irradiation induced deep and shallow impurities

    NASA Astrophysics Data System (ADS)

    Treberspurg, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Krammer, Manfred; Valentan, Manfred

    2013-12-01

    Silicon Detectors close to the interaction point of the High Luminosity Large Hardron Collider (HL-LHC) have to withstand a harsh irradiation environment. In order to evaluate the behaviour of shallow and deep defects, induced by neutron irradiation, spreading resistance resistivity measurements and capacitance voltage measurements have been performed. These measurements, deliver information about the profile of shallow impurities after irradiation as well as indications of deep defects in the Space Charge Region (SCR) and the Electrical Neutral Bulk (ENB). By considering the theoretical background of the measurement both kinds of defects can be investigated independently from each other.

  16. Composite accidental axions

    NASA Astrophysics Data System (ADS)

    Redi, Michele; Sato, Ryosuke

    2016-05-01

    We present several models where the QCD axion arises accidentally. Confining gauge theories can generate axion candidates whose properties are uniquely determined by the quantum numbers of the new fermions under the Standard Model. The Peccei-Quinn symmetry can emerge accidentally if the gauge theory is chiral. We generalise previous constructions in a unified framework. In some cases these models can be understood as the deconstruction of 5-dimensional gauge theories where the Peccei-Quinn symmetry is protected by locality but more general constructions are possible.

  17. Epidemiology of accidental radiation exposures.

    PubMed Central

    Cardis, E

    1996-01-01

    Much of the information on the health effects of radiation exposure available to date comes from long-term studies of the atomic bombings in Hiroshima and Nagasaki. Accidental exposures, such as those resulting from the Chernobyl and Kyshtym accidents, have as yet provided little information concerning health effects of ionizing radiation. This paper will present the current state of our knowledge concerning radiation effects, review major large-scale accidental radiation exposures, and discuss information that could be obtained from studies of accidental exposures and the types of studies that are needed. PMID:8781398

  18. Accidental hanging by a T-shirt collar in a man with morphine intoxication: an unusual case.

    PubMed

    Kodikara, Sarathchandra; Alagiyawanna, Ramesh

    2011-09-01

    Accidental hanging is rare across all age groups, and it is even rarer in the adult population except in autoerotic asphyxia. Few cases have been reported in the literature, which describe unusual patterns of accidental hanging. This article focuses on an unusual pattern of accidental hanging of a 25-year-old man, who was in a state of morphine-induced central nervous system depression and found dead in a sitting position with the collar of his T-shirt hanging off a jutting-out root of a tree. The hanged collar acted as a ligature compressing the neck.

  19. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a) (1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death and...

  20. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death and...

  1. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death and...

  2. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death and...

  3. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death and...

  4. Irradiation-induced effects of proton irradiation on zirconium carbides with different stoichiometries

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Y. Huang; B.R. Maier; T.R. Allen

    2014-10-01

    Zirconium carbide (ZrC) is being considered for utilization in deep burn TRISO fuel particles for hightemperature, gas-cooled reactors. Zirconium carbide has a cubic B1 type crystal structure along with a very high melting point (3420 ?C), exceptional hardness and good thermal and electrical conductivities. Understanding the ZrC irradiation response is crucial for establishing ZrC as an alternative component in TRISO fuel. Until now, very few studies on irradiation effects on ZrC have been released and fundamental aspects of defect evolution and kinetics are not well understood although some atomistic simulations and phenomenological studies have been performed. This work was carriedmore » out to understand the damage evolution in float-zone refined ZrC with different stoichiometries. Proton irradiations at 800 ?C up to doses of 3 dpa were performed on ZrCx (where x ranges from 0.9 to 1.2) to investigate the damage evolution. The irradiation-induced defects, such as density of dislocation loops, at different stoichiometries and doses which were characterized by transmission electron microscopy (TEM) is presented and discussed.« less

  5. Effect of Bifidobacterium breve B-3 on skin photoaging induced by chronic UV irradiation in mice.

    PubMed

    Satoh, T; Murata, M; Iwabuchi, N; Odamaki, T; Wakabayashi, H; Yamauchi, K; Abe, F; Xiao, J Z

    2015-01-01

    Probiotics have been shown to have a preventative effect on skin photoaging induced by short term UV irradiation, however, the underlying mechanisms and the effect of probiotics on skin photoaging induced by chronic UV irradiation remain unclear. In this study, we investigated the effect of Bifidobacterium breve B-3 on skin photoaging induced by chronic UV irradiation in hairless mice. Mice were irradiated with UVB three times weekly and orally administered B. breve B-3 (2×10(9) cfu/mouse /day) for 7 weeks. Nonirradiated mice and UVB-irradiated mice without probiotic treatment were used as controls. B. breve B-3 significantly suppressed the changes of transepidermal water loss, skin hydration, epidermal thickening and attenuated the damage to the tight junction structure and basement membrane induced by chronic UVB irradiation. Administration of B. breve B-3 tended to suppress the UV-induced interleukin-1β production in skin (P=0.09). These results suggest that B. breve B-3 could potentially be used to prevent photoaging induced by chronic UV irradiation.

  6. Renal effects of renal x irradiation and induced autoallergic glomerulonephritis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rappaport, D.S.; Casarett, G.W.

    1979-09-01

    This study was conducted to determine what influence a single large x-ray exposure of kidney has on the development and course of an experimental autoallergic glomerulonephritis (EAG) in rats. EAG was induced in female Sprague-Dawley rats by immunization with Bordetella pertussis vaccine and homogenate of homologous kidney tissue and Freund's complete adjuvant. Progressive arteriolonephrosclerosis (ANS) was observed in right (irradiated) kidneys following unilateral renal irradiation (1500 rad). Rats were either immunized, sham-immunized, irradiated, sham-irradiated, or both immunized and irradiated. Light and immunofluorescent microscopic observation, urine protein content, and kidney weights were evaluated. In immunized-irradiated animals the effects of irradiation andmore » immunization were largely additive. Immunization did not considerably influence the development and course of ANS and irradiation did not considerably influence the development and course of EAG.« less

  7. Irradiation induces regionally specific alterations in pro-inflammatory environments in rat brain

    PubMed Central

    Lee, Won Hee; Sonntag, William E.; Mitschelen, Matthew; Yan, Han; Lee, Yong Woo

    2010-01-01

    Purpose Pro-inflammatory environments in the brain have been implicated in the onset and progression of neurological disorders. In the present study, we investigate the hypothesis that brain irradiation induces regionally specific alterations in cytokine gene and protein expression. Materials and methods Four month old F344 × BN rats received either whole brain irradiation with a single dose of 10 Gy γ-rays or sham-irradiation, and were maintained for 4, 8, and 24 h following irradiation. The mRNA and protein expression levels of pro-inflammatory mediators were analysed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and immunofluorescence staining. To elucidate the molecular mechanisms of irradiation-induced brain inflammation, effects of irradiation on the DNA-binding activity of pro-inflammatory transcription factors were also examined. Results A significant and marked up-regulation of mRNA and protein expression of pro-inflammatory mediators, including tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and monocyte chemoattractant protein-1 (MCP-1), was observed in hippocampal and cortical regions isolated from irradiated brain. Cytokine expression was regionally specific since TNF-α levels were significantly elevated in cortex compared to hippocampus (57% greater) and IL-1β levels were elevated in hippocampus compared to cortical samples (126% greater). Increases in cytokine levels also were observed after irradiation of mouse BV-2 microglial cells. A series of electrophoretic mobility shift assays (EMSA) demonstrated that irradiation significantly increased activation of activator protein-1 (AP-1), nuclear factor-κB (NF-κB), and cAMP response element-binding protein (CREB). Conclusion The present study demonstrated that whole brain irradiation induces regionally specific pro-inflammatory environments through activation of AP-1, NF-κB, and CREB and overexpression of TNF-α, IL

  8. Aplasia Ras homologue member Ⅰ overexpression inhibits tumor growth and induces apoptosis through inhibition of PI3K/Akt survival pathways in human osteosarcoma MG-63 cells in culture.

    PubMed

    Ye, Kaishan; Wang, Shuanke; Yang, Yong; Kang, Xuewen; Wang, Jing; Han, Hua

    2015-09-01

    Aplasia Ras homologue member Ⅰ (ARHI), an imprinted tumor-suppressor gene, is downregulated in various types of cancer. However, the expression, function and specific mechanisms of ARHI in human osteosarcoma (OS) cells remain unclear. The aim of the present study was to assess the effect of ARHI on OS cell proliferation and apoptosis and its associated mechanism. In the study, ARHI mRNA and protein levels were markedly downregulated in OS cells compared with the human osteoblast precursor cell line hFOB1.19. By generating stable transfectants, ARHI was overexpressed in OS cells that had low levels of ARHI. Overexpression of ARHI inhibited cell viability and proliferation and induced apoptosis. However, caspase‑3 activity was not changed by ARHI overexpression. In addition, phosphorylated Akt protein expression decreased in the ARHI overexpression group compared to that in the control vector group. The knockdown of ARHI also resulted in the promotion of cell proliferation and the attenuation of apoptosis in MG‑63 cells. Additionally, ARHI silencing increased the level of p‑Akt. The present results indicate that ARHI inhibits OS cell proliferation and may have a key role in the development of OS.

  9. Modelling irradiation-induced softening in BCC iron by crystal plasticity approach

    NASA Astrophysics Data System (ADS)

    Xiao, Xiazi; Terentyev, Dmitry; Yu, Long; Song, Dingkun; Bakaev, A.; Duan, Huiling

    2015-11-01

    Crystal plasticity model (CPM) for BCC iron to account for radiation-induced strain softening is proposed. CPM is based on the plastically-driven and thermally-activated removal of dislocation loops. Atomistic simulations are applied to parameterize dislocation-defect interactions. Combining experimental microstructures, defect-hardening/absorption rules from atomistic simulations, and CPM fitted to properties of non-irradiated iron, the model achieves a good agreement with experimental data regarding radiation-induced strain softening and flow stress increase under neutron irradiation.

  10. Accidental sulfur mustard exposure: A case report.

    PubMed

    Schmidt, Annette; Steinritz, Dirk; Rudolf, Klaus-Dieter; Thiermann, Horst; Striepling, Enno

    2018-09-01

    The clinical progression following a sulfur mustard-induced skin exposure is well documented in the literature. Upon skin contact and a characteristic latency period, sulfur mustard (SM) causes erythema, blister formation and ulceration, which is associated with wound healing disorders that may require surgical treatment. Here, we present a case report of accidental exposure to SM in a laboratory setting which required surgical treatment of the skin. The case was illustrated at close intervals over a period of two years and underlines that exposure to SM has to be taken into account when typical clinical symptoms occur. Moreover skin grafts appear to be effective in SM-induced non healing skin ulcerations. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. From labyrinthine aplasia to otocyst deformity.

    PubMed

    Giesemann, Anja Maria; Goetz, Friedrich; Neuburger, Jürgen; Lenarz, Thomas; Lanfermann, Heinrich

    2010-02-01

    Inner ear malformations (IEMs) are rare and it is unusual to encounter the rarest of them, namely labyrinthine aplasia (LA) and otocyst deformity. They do, however, provide useful pointers as to the early embryonic development of the ear. LA is characterised as a complete absence of inner ear structures. While some common findings do emerge, a clear definition of the otocyst deformity does not exist. It is often confused with the common cavity first described by Edward Cock. Our purpose was to radiologically characterise LA and otocyst deformity. Retrospective analysis of CT and MRI data from four patients with LA or otocyst deformity. Middle and inner ear findings were categorised by two neuroradiologists. The bony carotid canal was found to be absent in all patients. Posterior located cystic structures were found in association with LA and otocyst deformity. In the most severe cases, only soft tissue was present at the medial border of the middle ear cavity. The individuals with otocyst deformity also had hypoplasia of the petrous apex bone. These cases demonstrate gradual changes in the two most severe IEMs. Clarification of terms was necessary and, based on these findings, we propose defining otocyst deformity as a cystic structure in place of the inner ear, with the cochlea, IAC and carotid canal absent. This condition needs to be differentiated from the common cavity described by Edward Cook. A clear definition of inner ear malformations is essential if outcomes following cochlear implantation are to be compared.

  12. [Accidental hanging during auto-erotic practices].

    PubMed

    Vieira, D N; da Silva, A G

    1989-01-01

    An unusual case of accidental hanging during autoerotic practices in a 25-year-old male student is described and the autoerotic asphyxia syndrome briefly discussed. The authors stressed the importance of a correct diagnostic of accidental death in these cases.

  13. Phase change in CoTi2 induced by MeV electron irradiation

    NASA Astrophysics Data System (ADS)

    Zensho, Akihiro; Sato, Kazuhisa; Yasuda, Hidehiro; Mori, Hirotaro

    2018-07-01

    The phase change induced by MeV electron irradiation in the intermetallic compound E93-CoTi2 was investigated using high-voltage electron microscopy. Under MeV electron irradiation, CoTi2 was first transformed into an amorphous phase and, with continued irradiation, crystallite formation in the amorphous phase (i.e. formation of crystallites of a solid-solution phase within the amorphous phase) was induced. The critical temperature for amorphisation was around 250 K. The total dose (dpa) required for crystallite formation (i.e. that required for partial crystallisation) was high (i.e. 27-80 dpa) and, even after prolonged irradiation, the amorphous phase was retained in the irradiated sample. Such partial crystallisation behaviour of amorphous Co33Ti67 was clearly different from the crystallisation behaviour (i.e. amorphous-to-solid solution, polymorphous transformation) of amorphous Cr67Ti33 reported in the literature. A possible cause of the difference is discussed.

  14. Safety and efficacy of intravenous administration for tranexamic acid-induced emesis in dogs with accidental ingestion of foreign substances.

    PubMed

    Orito, Kensuke; Kawarai-Shimamura, Asako; Ogawa, Atsushi; Nakamura, Atsushi

    2017-12-22

    A prospective observational study was performed in canine clinical medicine to evaluate the emetic action and adverse effects of tranexamic acid. Veterinarians treated 137 dogs with a single dose of tranexamic acid (50 mg/kg, IV) after accidental ingestion of foreign substances. If needed, a second (median, 50 mg/kg; range, 20-50 mg/kg, IV) or third dose (median, 50 mg/kg; range, 25-50 mg/kg, IV) was administered. Tranexamic acid induced emesis in 116 of 137 (84.7%) dogs. Median time to onset of emesis was 116.5 sec (range, 26-370 sec), median duration of emesis was 151.5 sec (range, 30-780 sec), and median number of emesis episodes was 2 (range, 1-8). Second and third administrations of tranexamic acid induced emesis in 64.7 and 66.7% of dogs, respectively. In total, IV administration of tranexamic acid successfully induced emesis in 129 of 137 (94.2%) dogs. Adverse effects included a tonic-clonic convulsion and hemostatic disorder in two different dogs, both of which recovered after receiving medical care. Tranexamic acid induced emesis in most dogs following a single-dose. When a single dose was not sufficient, an additional dosage effectively induced emesis. Overall, adverse effects were considered low and self-limiting.

  15. Gastroprotective effect of kefir on ulcer induced in irradiated rats.

    PubMed

    Fahmy, Hanan A; Ismail, Amel F M

    2015-03-01

    The current study was designed to investigate the protective effect of kefir milk on ethanol-induced gastric ulcers in γ-irradiated rats. The results of the present study revealed that treatment with γ-irradiation and/or ethanol showed a significant increase in ulcers number, total acidity, peptic, H(+)K(+)ATPase, MMP-2 and MMP-9 activities and MDA level, which were accompanied by a significant decrease in the mucus content, the stomach GSH level, the GSH-Px activity and DNA damage. Pre-treatment with kefir milk exert significant improvement in all the tested parameters. Kefir milk exerts comparable effect to that of the antiulcer drug ranitidine. In conclusion, the present study revealed that oral administration of kefir milk prevents ethanol-induced gastric ulcer in γ-irradiated rats that could attribute to its antioxidant, anti-apoptotic and radio-protective activities. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Accidental poisoning with deadly nightshade berries: a case report.

    PubMed

    Trabattoni, G; Visintini, D; Terzano, G M; Lechi, A

    1984-12-01

    A case of acute accidental poisoning with deadly nightshade (Atropa belladonna) berries is reported. The patient was an elderly but healthy man who soon recovered. On the one hand, the clinical picture looked similar to that of delirium tremens; on the other, there were myoclonic jerks and signs of extrapyramidal involvement to suggest the onset of subacute dementia. The electroencephalogram findings confirmed those already reported during experimentally induced intoxication after ingestion of atropine in man.

  17. Analysis of strain-induced crystallinity in neutron-irradiated amorphous PET fiber

    NASA Astrophysics Data System (ADS)

    Mallick, B.

    2015-05-01

    Polyethylene terephthalate (PET) fiber of 2.2 denier per filament has been irradiated with 4.44-MeV fast neutron beam at different low doses: 0.58-2,513.5 mGy. The variation of crystallinity because of neutron irradiation straining in PET filaments has been investigated. Study of the effects of irradiation by using X-ray diffraction and differential scanning calorimetry technique confirms the radiation-induced microstrain-dependent crystallinity of PET fiber.

  18. [THREE CASES OF ACCIDENTAL AUTO-INJECTION OF ADRENALINE].

    PubMed

    Yanagida, Noriyuki; Iikura, Katsuhito; Ogura, Kiyotake; Wang, Ling-jen; Asaumi, Tomoyuki; Sato, Sakura; Ebisawa, Motohiro

    2015-12-01

    Reports on accidental auto-injection of adrenaline are few. We encountered three cases of accidental injection of adrenaline. In this study, we have examined and reported the clinical courses and symptoms of our cases. CASE 1 involved a female physician in her 50s who had attended an explanatory meeting on auto-injection of adrenaline. She mistook EpiPen® to be the EpiPen trainer and accidentally injected herself with 0.3 mg EpiPen®. Her systolic/diastolic pressure peaked at 7 min to reach 144/78 mmHg and decreased to 120/77 mmHg at 14 min. Except for palpitation after 7 min, the only subjective symptom was local pain at the injection site. CASE 2 was noted in a 6-year-old boy. He accidentally pierced his right forefinger with 0.15 mg EpiPen®, and after 20 min, his right forefinger was swollen. The swelling improved 80 min after the accidental injection. CASE 3 was noted in a 4-year-old girl. She accidentally injected herself with 0.15 mg EpiPen®. Her systolic/diastolic pressure peaked at 23 min to reach 123/70 mmHg and decreased to 96/86 mmHg at 28 min. Severe adverse effects of accidental auto-injection of adrenaline were not observed in these three cases. Our findings suggest that while handling adrenaline auto-injectors, we should keep in mind the possibility of accidental injection.

  19. Characterisation of irradiation-induced defects in ZnO single crystals

    NASA Astrophysics Data System (ADS)

    Prochazka, I.; Cizek, J.; Lukac, F.; Melikhova, O.; Valenta, J.; Havranek, V.; Anwand, W.; Skuratov, V. A.; Strukova, T. S.

    2016-01-01

    Positron annihilation spectroscopy (PAS) combined with optical methods was employed for characterisation of defects in the hydrothermally grown ZnO single crystals irradiated by 167 MeV Xe26+ ions to fluences ranged from 3×1012 to 1×1014 cm-2. The positron lifetime (LT), Doppler broadening as well as slow-positron implantation spectroscopy (SPIS) techniques were involved. The ab-initio theoretical calculations were utilised for interpretation of LT results. The optical transmission and photoluminescence measurements were conducted, too. The virgin ZnO crystal exhibited a single component LT spectrum with a lifetime of 182 ps which is attributed to saturated positron trapping in Zn vacancies associated with hydrogen atoms unintentionally introduced into the crystal during the crystal growth. The Xe ion irradiated ZnO crystals have shown an additional component with a longer lifetime of ≈ 360 ps which comes from irradiation-induced larger defects equivalent in size to clusters of ≈10 to 12 vacancies. The concentrations of these clusters were estimated on the basis of combined LT and SPIS data. The PAS data were correlated with irradiation induced changes seen in the optical spectroscopy experiments.

  20. Study on DNA Damage Induced by Neon Beam Irradiation in Saccharomyces Cerevisiae

    NASA Astrophysics Data System (ADS)

    Lu, Dong; Li, Wenjian; Wu, Xin; Wang, Jufang; Ma, Shuang; Liu, Qingfang; He, Jinyu; Jing, Xigang; Ding, Nan; Dai, Zhongying; Zhou, Jianping

    2010-12-01

    Yeast strain Saccharomyces cerevisiae was irradiated with different doses of 85 MeV/u 20Ne10+ to investigate DNA damage induced by heavy ion beam in eukaryotic microorganism. The survival rate, DNA double strand breaks (DSBs) and DNA polymorphic were tested after irradiation. The results showed that there were substantial differences in DNA between the control and irradiated samples. At the dose of 40 Gy, the yeast cell survival rate approached 50%, DNA double-strand breaks were barely detectable, and significant DNA polymorphism was observed. The alcohol dehydrogenase II gene was amplified and sequenced. It was observed that base changes in the mutant were mainly transversions of T→G and T→C. It can be concluded that heavy ion beam irradiation can lead to change in single gene and may be an effective way to induce mutation.

  1. Use of Nandrolone Decanoate in Treatment of Pure Red Cell Aplasia Secondary to Diclofenac Administration: A Case Report.

    PubMed

    de Marchi, Paula Nassar; Sueur Vieira, André Nanny Le; Antunes Ribeiro, José Francisco; Geraldes, Silvano Salgueiro; Rodrigues Ramos, Paulo Roberto; Melchert, Alessandra; Guimarães-Okamoto, Priscylla Tatiana Chalfun

    2017-03-01

    Pure red cell aplasia (PRCA) is a disorder that leads to a nonregenerative anemia that results from erythroid precursors failing to reach maturity in the bone marrow, whereas the numbers of mature myeloid and megakaryocytic cells remain normal. PRCA can be induced by autoimmune processes, infections, drugs, toxins, and radiation, and is diagnosed by a bone marrow cytology examination after excluding the most common causes of nonregenerative anemia. Immunosuppressive therapies are used to treat PRCA, and usually involve the use of glucocorticoids, cyclosporin, or azathioprine. Alternatively, although little studied in veterinary medicine, drugs which stimulate bone marrow (e.g., nandrolone decanoate) have been mentioned as possible therapeutic agents. A case of PRCA that presented at the Veterinary Teaching Hospital of the Faculty of Veterinary Medicine and Animal Science (UNESP)-Botucatu, Brazil showed a good therapeutic response to weekly administration of nandrolone decanoate. Therefore, it was concluded that bone marrow stimulants might improve the quality of life of PRCA patients, provided they are used with caution and under close clinical supervision. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Structural and optical properties improvements of PVP/gelatin blends induced by neutron irradiation

    NASA Astrophysics Data System (ADS)

    Basha, Mohammad Ahmad-Fouad; Hassan, Mohamed Ahmed

    2018-05-01

    Blends of polyvinylpyrrolidone and gelatin were prepared in three different concentrations to study the modifications in their structural and optical properties induced by neutron irradiations with different neutron fluence values from 108 up to 1011 neutron/cm2. X-ray spectroscopy revealed that the irradiation has induced a recrystallization phenomenon in the studied blends and the crystallinity index increased by increasing the neutron fluence due to the breaking of the crystallites. Fourier-transform infrared spectroscopy came to confirm the existence of interactions between interchain groups and a higher compatibility for the irradiated blends. The irradiation induced defects inside the material were responsible for the change in their optical and structural properties. The creation of free radicals or ions inside the conduction bands has led to the increase in the number of carriers on localized states; this has caused the increase in optical conductivity of the irradiated blends as a result of decreasing the energy gaps by increasing the neutron fluence. Results may widen the applications of the gelatin based blends to include optoelectronic devices, organic light emitting devices, solar selective and anti-reflectance bio-coatings, optical organic glass and lenses.

  3. Reevaluation of induced radioactivity in 10MeV electron-irradiated pepper for public acceptance

    NASA Astrophysics Data System (ADS)

    Furuta, M.; Katayama, T.; Ito, N.; Mizohata, A.; Toratani, H.; Takeda, A.

    In order to examine whether or not radioactivity could be produced in black pepper and white pepper with 10MeV electrons, the sample was irradiated with 10MeV electrons from a linear accelerator and its radioactivity was measured by gamma-ray spectrometry and beta-ray counting. The patterns of gamma-ray spectra showed that there was no difference between the irradiated and the non-irradiated samples, suggesting that the induced radioactivity in the irradiated sample was below the detection limit of its induced radioactivity. For further estimation, elemental composition was analyzed and photonuclear reactions which could produce radioactivity in the sample were investigated based on the data already published. Some photonuclear target nuclides in the list were spiked to the sample, being checked in the same way. Although short lived photonuclear products were observed, these radioactivities were found to decrease below the detection limit in a week. It is concluded that the induced radioactivity in the 10MeV electron-irradiated pepper and hence, its biological effect is far smaller than the natural radioactivity arising from 40K contained in the non-irradiated sample.

  4. EPR spectra induced by gamma-irradiation of some dry medical herbs

    NASA Astrophysics Data System (ADS)

    Yordanov, N. D.; Lagunov, O.; Dimov, K.

    2009-04-01

    The radiation-induced EPR spectra in some medical herbs are reported. The samples studied are: (i) leaves of nettle, common balm, peppermint and thyme; (ii) stalks of common balm, thyme, milfoil, yarrow and marigold; (iii) blossoms of yarrow and marigold; (iv) blossoms and leaves of hawthorn and tutsan; and (v) roots of common valerian, nettle, elecampane (black and white), restharrows and carlina. Before irradiation all samples exhibit one weak anisotropic singlet EPR line with effective g-value of 2.0050±0.0002. The radiation-induced spectra fall into three groups. EPR spectra of irradiated blossoms of yarrow and marigold, stalks of common balm, thyme, tutsan and yarrow as well as roots of common valerian, nettle and elecampane (black and white) show "cellulose-like" EPR spectrum typical for irradiated plants. It is characterized by one intense central line with g=2.0050±0.0005 and two weak satellite lines situated ca. 30 G left and right to it. EPR spectra of gamma-irradiated restharrows and carlina are complex. They may be represented by one triplet corresponding to the "cellulose-like" EPR spectrum, one relatively intense singlet, situated in the center of the spectrum, and five weak additional satellite lines left and right to the center. The last spectrum was assigned as "carbohydrate-like" type. Only one intense EPR singlet with g=2.0048±0.0005 was recorded after irradiation of leaves of nettle and common balm. The lifetime of the radiation-induced EPR spectra was followed for a period of 3 months.

  5. Rebamipide alleviates radiation-induced colitis through improvement of goblet cell differentiation in mice.

    PubMed

    Jang, Hyosun; Park, Sunhoo; Lee, Janet; Myung, Jae Kyung; Jang, Won-Suk; Lee, Sun-Joo; Myung, Hyunwook; Lee, Changsun; Kim, Hyewon; Lee, Seung-Sook; Jin, Young-Woo; Shim, Sehwan

    2018-04-01

    Radiation-induced colitis is a common clinical problem associated with radiotherapy and accidental exposure to ionizing radiation. Goblet cells play a pivotal role in the intestinal barrier against pathogenic bacteria. Rebamipide, an anti-gastric ulcer drug, has the effects to promote goblet cell proliferation. The aim of this study was to investigate whether radiation-induced colonic injury could be alleviated by rebamipide. This study orally administered rebamipide for 6 days to mice, which were subjected to 13 Gy abdominal irradiation, to evaluate the therapeutic effects of rebamipide against radiation-induced colitis. To confirm the effects of rebamipide on irradiated colonic epithelial cells, this study used the HT29 cell line. Rebamipide clearly alleviated the acute radiation-induced colitis, as reflected by the histopathological data, and significantly increased the number of goblet cells. The drug also inhibited intestinal inflammation and protected from bacterial translocation during acute radiation-induced colitis. Furthermore, rebamipide significantly increased mucin 2 expression in both the irradiated mouse colon and human colonic epithelial cells. Additionally, rebamipide accelerated not only the recovery of defective tight junctions but also the differentiation of impaired goblet cells in an irradiated colonic epithelium, which indicates that rebamipide has beneficial effects on the colon. Rebamipide is a therapeutic candidate for radiation-induced colitis, owing to its ability to inhibit inflammation and protect the colonic epithelial barrier. © 2017 The Authors Journal of Gastroenterology and Hepatology published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  6. Cardiolipin-Specific Peroxidase Reactions of Cytochrome c in Mitochondria During Irradiation-Induced Apoptosis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Belikova, Natalia A.; Jiang Jianfei; Tyurina, Yulia Y.

    2007-09-01

    Purpose: To determine whether cytochrome c (cyt c) content and associated cardiolipin oxidation can be determinants of cell sensitivity to irradiation-induced apoptosis. Methods and Materials: The small interfering RNA (siRNA) approach was used to engineer HeLa cells with lowered contents of cyt c (14%, HeLa 1.2 cells). Cells were treated by {gamma}-irradiation (in doses of 5-40 Gy). Lipid oxidation was characterized by electrospray ionization mass spectrometry analysis and fluorescence high-performance liquid chromatography-based Amplex Red assay. Release of a proapoptotic factor (cyt c, Smac/DIABLO) was detected by Western blotting. Apoptosis was revealed by caspase-3/7 activation and phosphatidylserine externalization. Results: Irradiation causedmore » selective accumulation of hydroperoxides in cardiolipin (CL) but not in other phospholipids. HeLa 1.2 cells responded by a lower irradiation-induced accumulation of CL oxidation products than parental HeLa cells. Proportionally decreased release of a proapoptotic factor, Smac/DIABLO, was detected in cyt c-deficient cells after irradiation. Caspase-3/7 activation and phosphatidylserine externalization were proportional to the cyt c content in cells. Conclusions: Cytochrome c is an important catalyst of CL peroxidation, critical to the execution of the apoptotic program. This new role of cyt c in irradiation-induced apoptosis is essential for the development of new radioprotectors and radiosensitizers.« less

  7. A phase field model for segregation and precipitation induced by irradiation in alloys

    NASA Astrophysics Data System (ADS)

    Badillo, A.; Bellon, P.; Averback, R. S.

    2015-04-01

    A phase field model is introduced to model the evolution of multicomponent alloys under irradiation, including radiation-induced segregation and precipitation. The thermodynamic and kinetic components of this model are derived using a mean-field model. The mobility coefficient and the contribution of chemical heterogeneity to free energy are rescaled by the cell size used in the phase field model, yielding microstructural evolutions that are independent of the cell size. A new treatment is proposed for point defect clusters, using a mixed discrete-continuous approach to capture the stochastic character of defect cluster production in displacement cascades, while retaining the efficient modeling of the fate of these clusters using diffusion equations. The model is tested on unary and binary alloy systems using two-dimensional simulations. In a unary system, the evolution of point defects under irradiation is studied in the presence of defect clusters, either pre-existing ones or those created by irradiation, and compared with rate theory calculations. Binary alloys with zero and positive heats of mixing are then studied to investigate the effect of point defect clustering on radiation-induced segregation and precipitation in undersaturated solid solutions. Lastly, irradiation conditions and alloy parameters leading to irradiation-induced homogeneous precipitation are investigated. The results are discussed in the context of experimental results reported for Ni-Si and Al-Zn undersaturated solid solutions subjected to irradiation.

  8. The characterization and evaluation of accidental explosions

    NASA Technical Reports Server (NTRS)

    Strehlow, R. A.; Baker, W. E.

    1975-01-01

    Accidental explosions are discussed from a number of viewpoints. First, all accidental explosions, intentional explosions and natural explosions are characterized by type. Second, the nature of the blast wave produced by an ideal (point source or HE) explosion is discussed to form a basis for describing how other explosion processes yield deviations from ideal blast wave behavior. The current status blast damage mechanism evaluation is also discussed. Third, the current status of our understanding of each different category of accidental explosions is discussed in some detail.

  9. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic products...

  10. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic products...

  11. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic products...

  12. Safety and efficacy of intravenous administration for tranexamic acid-induced emesis in dogs with accidental ingestion of foreign substances

    PubMed Central

    ORITO, Kensuke; KAWARAI-SHIMAMURA, Asako; OGAWA, Atsushi; NAKAMURA, Atsushi

    2017-01-01

    A prospective observational study was performed in canine clinical medicine to evaluate the emetic action and adverse effects of tranexamic acid. Veterinarians treated 137 dogs with a single dose of tranexamic acid (50 mg/kg, IV) after accidental ingestion of foreign substances. If needed, a second (median, 50 mg/kg; range, 20–50 mg/kg, IV) or third dose (median, 50 mg/kg; range, 25–50 mg/kg, IV) was administered. Tranexamic acid induced emesis in 116 of 137 (84.7%) dogs. Median time to onset of emesis was 116.5 sec (range, 26–370 sec), median duration of emesis was 151.5 sec (range, 30–780 sec), and median number of emesis episodes was 2 (range, 1–8). Second and third administrations of tranexamic acid induced emesis in 64.7 and 66.7% of dogs, respectively. In total, IV administration of tranexamic acid successfully induced emesis in 129 of 137 (94.2%) dogs. Adverse effects included a tonic-clonic convulsion and hemostatic disorder in two different dogs, both of which recovered after receiving medical care. Tranexamic acid induced emesis in most dogs following a single-dose. When a single dose was not sufficient, an additional dosage effectively induced emesis. Overall, adverse effects were considered low and self-limiting. PMID:29093310

  13. Protection of Radiation-Induced Damage to the Hematopoietic System, Small Intestine and Salivary Glands in Rats by JNJ7777120 Compound, a Histamine H4 Ligand

    PubMed Central

    Martinel Lamas, Diego J.; Carabajal, Eliana; Prestifilippo, Juan P.; Rossi, Luis; Elverdin, Juan C.; Merani, Susana; Bergoc, Rosa M.; Rivera, Elena S.; Medina, Vanina A.

    2013-01-01

    Based on previous data on the histamine radioprotective effect on highly radiosensitive tissues, in the present work we aimed at investigating the radioprotective potential of the H4R ligand, JNJ7777120, on ionizing radiation-induced injury and genotoxic damage in small intestine, salivary glands and hematopoietic tissue. For that purpose, rats were divided into 4 groups. JNJ7777120 and JNJ7777120-irradiated groups received a daily subcutaneous JNJ7777120 injection (10 mg/kg) starting 24 h before irradiation. Irradiated groups received a single dose of 5 Gy on whole-body using Cesium-137 source and were sacrificed 3 or 30 days after irradiation. Tissues were removed, fixed, stained with hematoxylin and eosin or PAS staining and histological characteristics were evaluated. Proliferative and apoptotic markers were studied by immunohistochemistry, while micronucleus assay was performed to evaluate DNA damage. Submandibular gland (SMG) function was evaluated by methacholine-induced salivation. Results indicate that JNJ7777120 treatment diminished mucosal atrophy and preserved villi and the number of crypts after radiation exposure (240±8 vs. 165±10, P<0.01). This effect was associated to a reduced apoptosis and DNA damage in intestinal crypts. JNJ7777120 reduced radiation-induced aplasia, preserving medullar components and reducing formation of micronucleus and also it accelerated bone marrow repopulation. Furthermore, it reduced micronucleus frequency in peripheral blood (27±8 vs. 149±22, in 1,000 erythrocytes, P<0.01). JNJ7777120 completely reversed radiation-induced reduced salivation, conserving glandular mass with normal histological appearance and reducing apoptosis and atrophy of SMG. JNJ7777120 exhibits radioprotective effects against radiation-induced cytotoxic and genotoxic damages in small intestine, SMG and hematopoietic tissues and, thus, could be of clinical value for patients undergoing radiotherapy. PMID:23922686

  14. Low-dose gamma-ray irradiation induces translocation of Nrf2 into nuclear in mouse macrophage RAW264.7 cells.

    PubMed

    Tsukimoto, Mitsutoshi; Tamaishi, Nana; Homma, Takujiro; Kojima, Shuji

    2010-01-01

    The transcription factor nuclear erythroid-derived 2-related factor 2 (Nrf2) regulates expression of genes encoding antioxidant proteins involved in cellular redox homeostasis, while gamma-ray irradiation is known to induce reactive oxygen species in vivo. Although activation of Nrf2 by various stresses has been studied, it has not yet been determined whether ionizing irradiation induces activation of Nrf2. Therefore, we investigated activation of Nrf2 in response to gamma-irradiation in mouse macrophage RAW264.7 cells. Irradiation of cells with gamma-rays induced an increase of Nrf2 expression. Even 0.1 Gy of gamma-irradiation induced a translocation of Nrf2 from cytoplasm to the nucleus, indicating the activation of Nrf2 by low-dose irradiation. Expression of heme oxygenase-1, which is regulated by Nrf2, was also increased at 24 h after irradiation with more than 0.1 Gy of gamma-rays. Furthermore, the activation of Nrf2 was suppressed by U0126, which is an inhibitor of the extracellular signal regulated protein kinase 1/2 (ERK1/2) pathway, suggesting involvement of ERK1/2-dependent pathway in the irradiation-induced activation of Nrf2. Our results indicate that low-dose gamma-irradiation induces activation of Nrf2 through ERK1/2-dependent pathways.

  15. Defects with Deep Levels in GaAs Induced by Plastic Deformation and Electron Irradiation

    NASA Astrophysics Data System (ADS)

    Haga, Toru; Suezawa, Masashi; Sumino, Koji

    1988-10-01

    Defects with deep electronic energy levels induced by plastic deformation at 450°C or electron irradiation at room temperature in boat-grown GaAs crystals are investigated by means of optical absorption. The optical absorption spectra associated with the induced defects are compared with that of grown-in defects EL2. Thermal stabilities of the defects are studied by tracing the changes in the absorption spectra due to isochronal annealing of the specimens. The defects induced by the above two procedures are identified not to be EL2, even though some part of the defects gives rise to absorption similar to that caused by EL2 in the spectral shape. The absorptions in both the deformed and the irradiated samples are mostly photo-unquenchable. Deformation-induced defects responsible for this absorption are found to be AsGa antisite-related defects which are less thermally stable than EL2. Irradiation-induced defects giving rise to this kind of absorption are far more unstable in comparison with the deformation-induced defects, and are mostly eliminated by annealing at temperatures lower than 300°C.

  16. Investigation of thermoluminescence properties of mobile phone screen displays as dosimeters for accidental dosimetry

    NASA Astrophysics Data System (ADS)

    Mrozik, Anna; Marczewska, B.; Bilski, P.; Kłosowski, M.

    2014-11-01

    The rapid assessment of the radiation dose after unexpected exposure is a task of accidental dosimetry. In case of a radiological accident glasses originating from mobile phone screens, placed usually near the human body, could be used as emergency thermoluminescent (TL) personal dosimeters. The time between irradiation and TL readout is crucial and therefore preparation of the mobile phone screens and their readout conditions should be optimized. The influence of the samples etching, bleaching and selection of the optical filters based on measurement of the emission spectrum of irradiated glass samples during heating for different types of mobile phones were the subjects of our investigation. Obtained results showed that glasses extracted from different brands of mobile phones have different dosimetric properties but all of them give a luminescent signal which can be used to calculate the dose.

  17. Irradiation induces bone injury by damaging bone marrow microenvironment for stem cells

    PubMed Central

    Cao, Xu; Wu, Xiangwei; Frassica, Deborah; Yu, Bing; Pang, Lijuan; Xian, Lingling; Wan, Mei; Lei, Weiqi; Armour, Michael; Tryggestad, Erik; Wong, John; Wen, Chun Yi; Lu, William Weijia; Frassica, Frank J.

    2011-01-01

    Radiation therapy can result in bone injury with the development of fractures and often can lead to delayed and nonunion of bone. There is no prevention or treatment for irradiation-induced bone injury. We irradiated the distal half of the mouse left femur to study the mechanism of irradiation-induced bone injury and found that no mesenchymal stem cells (MSCs) were detected in irradiated distal femora or nonirradiated proximal femora. The MSCs in the circulation doubled at 1 week and increased fourfold after 4 wk of irradiation. The number of MSCs in the proximal femur quickly recovered, but no recovery was observed in the distal femur. The levels of free radicals were increased threefold at 1 wk and remained at this high level for 4 wk in distal femora, whereas the levels were increased at 1 wk and returned to the basal level at 4 wk in nonirradiated proximal femur. Free radicals diffuse ipsilaterally to the proximal femur through bone medullary canal. The blood vessels in the distal femora were destroyed in angiographic images, but not in the proximal femora. The osteoclasts and osteoblasts were decreased in the distal femora after irradiation, but no changes were observed in the proximal femora. The total bone volumes were not affected in proximal and distal femora. Our data indicate that irradiation produces free radicals that adversely affect the survival of MSCs in both distal and proximal femora. Irradiation injury to the vasculatures and the microenvironment affect the niches for stem cells during the recovery period. PMID:21220327

  18. Irradiation induces bone injury by damaging bone marrow microenvironment for stem cells.

    PubMed

    Cao, Xu; Wu, Xiangwei; Frassica, Deborah; Yu, Bing; Pang, Lijuan; Xian, Lingling; Wan, Mei; Lei, Weiqi; Armour, Michael; Tryggestad, Erik; Wong, John; Wen, Chun Yi; Lu, William Weijia; Frassica, Frank J

    2011-01-25

    Radiation therapy can result in bone injury with the development of fractures and often can lead to delayed and nonunion of bone. There is no prevention or treatment for irradiation-induced bone injury. We irradiated the distal half of the mouse left femur to study the mechanism of irradiation-induced bone injury and found that no mesenchymal stem cells (MSCs) were detected in irradiated distal femora or nonirradiated proximal femora. The MSCs in the circulation doubled at 1 week and increased fourfold after 4 wk of irradiation. The number of MSCs in the proximal femur quickly recovered, but no recovery was observed in the distal femur. The levels of free radicals were increased threefold at 1 wk and remained at this high level for 4 wk in distal femora, whereas the levels were increased at 1 wk and returned to the basal level at 4 wk in nonirradiated proximal femur. Free radicals diffuse ipsilaterally to the proximal femur through bone medullary canal. The blood vessels in the distal femora were destroyed in angiographic images, but not in the proximal femora. The osteoclasts and osteoblasts were decreased in the distal femora after irradiation, but no changes were observed in the proximal femora. The total bone volumes were not affected in proximal and distal femora. Our data indicate that irradiation produces free radicals that adversely affect the survival of MSCs in both distal and proximal femora. Irradiation injury to the vasculatures and the microenvironment affect the niches for stem cells during the recovery period.

  19. EPIDEMIOLOGY OF ACCIDENTAL POISONING

    PubMed Central

    Bissell, D. M.; McInnes, Robert S.

    1960-01-01

    In San Jose, California, studies of cases of accidental poisoning showed that the greatest hazard was to children 1 through 3 years of age. Drugs accounted for half the cases, household products for another third, and insecticides and rodenticides and others for the remainder. Most often poison material was within easy reach of the children. An analysis of families in which an accident occurred indicated that accidental poisoning might happen to any family. Since there was little after-effect of poisoning in cases in which treatment was obtained promptly, education directed toward getting prompt treatment seems most advisable. Community agencies interested in poison control need to focus their attention on parents of pre-school children. PMID:13801023

  20. Accidental death in autoerotic maneuvers.

    PubMed

    Focardi, Martina; Gualco, Barbara; Norelli, GianAristide

    2008-03-01

    The authors from the Florence Forensic Department present a case that demonstrates the paradigms attached to accidental deaths while performing autoerotic maneuvers. The incidents of such practices are underestimated and are only the tip of the iceberg since they do not represent the cases that are never reported due to successful practice. After analyzing the statistic data, the authors describe the case and discuss about the element that prove the accidental nature of the death and the importance of the correct application of forensic methodology at the scene and in the mortuary.

  1. Immune-mediated pure red cell aplasia in a domestic ferret.

    PubMed

    Malka, Shachar; Hawkins, Michelle G; Zabolotzky, Shanon M; Mitchell, Elizabeth B; Owens, Sean D

    2010-09-15

    An 8-month-old spayed female domestic ferret (Mustela putorius furo) was referred for examination to determine the cause of lethargy and severe anemia. Initial examination revealed that the ferret was lethargic but with appropriate mentation. The only other abnormal findings were severe pallor of the mucous membranes, nasal planum, and skin and a PCV of 8%. Pure red cell aplasia (PRCA) was diagnosed on the basis of cytologic evaluation of a bone marrow biopsy specimen. Medical treatment included blood transfusions, IM administration of iron dextran, oral administration of antimicrobials and gastrointestinal tract protectants, and SC administration of erythropoietin. Once PRCA was diagnosed, the ferret was orally administered prednisone, cyclosporine, and azathioprine. Nine months after onset of treatment, the PRCA was in remission and the ferret was doing well. Immunosuppressive treatment was discontinued at 14 months after onset of treatment, and 36 months after initial examination, the ferret appeared to be healthy. It is important that PRCA be considered as a differential diagnosis for a ferret with severe anemia. Prolonged immunosuppressive treatment was successful in the ferret described here.

  2. Electron irradiation induced phase separation in a sodium borosilicate glass

    NASA Astrophysics Data System (ADS)

    Sun, K.; Wang, L. M.; Ewing, R. C.; Weber, W. J.

    2004-06-01

    Electron irradiation induced phase separation in a sodium borosilicate glass was studied in situ by analytical electron microscopy. Distinctly separate phases that are rich in boron and silicon formed at electron doses higher than 4.0 × 10 11 Gy during irradiation. The separated phases are still in amorphous states even at a much high dose (2.1 × 10 12 Gy). It indicates that most silicon atoms remain tetrahedrally coordinated in the glass during the entire irradiation period, except some possible reduction to amorphous silicon. The particulate B-rich phase that formed at high dose was identified as amorphous boron that may contain some oxygen. Both ballistic and ionization processes may contribute to the phase separation.

  3. Defect-induced ferromagnetism in semiconductors: A controllable approach by particle irradiation

    NASA Astrophysics Data System (ADS)

    Zhou, Shengqiang

    2014-05-01

    Making semiconductors ferromagnetic has been a long dream. One approach is to dope semiconductors with transition metals (TM). TM ions act as local moments and they couple with free carriers to develop collective magnetism. However, there are no fundamental reasons against the possibility of local moment formation from localized sp states. Recently, ferromagnetism was observed in nonmagnetically doped, but defective semiconductors or insulators including ZnO and TiO2. This kind of observation challenges the conventional understanding of ferromagnetism. Often the defect-induced ferromagnetism has been observed in samples prepared under non-optimized condition, i.e. by accident or by mistake. Therefore, in this field theory goes much ahead of experimental investigation. To understand the mechanism of the defect-induced ferromagnetism, one needs a better controlled method to create defects in the crystalline materials. As a nonequilibrium and reproducible approach of inducing defects, ion irradiation provides such a possibility. Energetic ions displace atoms from their equilibrium lattice sites, thus creating mainly vacancies, interstitials or antisites. The amount and the distribution of defects can be controlled by the ion fluence and energy. By ion irradiation, we have generated defect-induced ferromagnetism in ZnO, TiO2 and SiC. In this short review, we also summarize some results by other groups using energetic ions to introduce defects, and thereby magnetism in various materials. Ion irradiation combined with proper characterizations of defects could allow us to clarify the local magnetic moments and the coupling mechanism in defective semiconductors. Otherwise we may have to build a new paradigm to understand the defect-induced ferromagnetism.

  4. A reevaluation of X-irradiation-induced phocomelia and proximodistal limb patterning.

    PubMed

    Galloway, Jenna L; Delgado, Irene; Ros, Maria A; Tabin, Clifford J

    2009-07-16

    Phocomelia is a devastating, rare congenital limb malformation in which the long bones are shorter than normal, with the upper portion of the limb being most severely affected. In extreme cases, the hands or fingers are attached directly to the shoulder and the most proximal elements (those closest to the shoulder) are entirely missing. This disorder, previously known in both autosomal recessive and sporadic forms, showed a marked increase in incidence in the early 1960s due to the tragic toxicological effects of the drug thalidomide, which had been prescribed as a mild sedative. This human birth defect is mimicked in developing chick limb buds exposed to X-irradiation. Both X-irradiation and thalidomide-induced phocomelia have been interpreted as patterning defects in the context of the progress zone model, which states that a cell's proximodistal identity is determined by the length of time spent in a distal limb region termed the 'progress zone'. Indeed, studies of X-irradiation-induced phocomelia have served as one of the two major experimental lines of evidence supporting the validity of the progress zone model. Here, using a combination of molecular analysis and lineage tracing in chick, we show that X-irradiation-induced phocomelia is fundamentally not a patterning defect, but rather results from a time-dependent loss of skeletal progenitors. Because skeletal condensation proceeds from the shoulder to fingers (in a proximal to distal direction), the proximal elements are differentially affected in limb buds exposed to radiation at early stages. This conclusion changes the framework for considering the effect of thalidomide and other forms of phocomelia, suggesting the possibility that the aetiology lies not in a defect in the patterning process, but rather in progenitor cell survival and differentiation. Moreover, molecular evidence that proximodistal patterning is unaffected after X-irradiation does not support the predictions of the progress zone model.

  5. Nickel nanowires mesh fabricated by ion beam irradiation-induced nanoscale welding for transparent conducting electrodes

    NASA Astrophysics Data System (ADS)

    Honey, S.; Ahmad, I.; Madhuku, M.; Naseem, S.; Maaza, M.; Kennedy, J. V.

    2017-07-01

    In this report, random nickel nanowires (Ni-NWs) meshes are fabricated by ions beam irradiation-induced nanoscale welding of NWs on intersecting positions. Ni-NWs are exposed to beam of 50 KeV Argon (Ar+) ions at various fluencies in the range ~1015 ions cm-2 to 1016 ions cm-2 at room temperature. Ni-NWs are welded due to accumulation of Ar+ ions beam irradiation-induced sputtered atoms on crossing positions. Ar+ ions irradiated Ni-NWs meshes are optically transparent and optical transparency is enhanced with increase in beam fluence of Ar+ ions. Ar+ ions beam irradiation-induced welded and optically transparent mesh is then exposed to 2.75 MeV hydrogen (H+) ions at fluencies 1  ×  1015 ions cm-2, 3  ×  1015 ions cm-2 and 1  ×  1016 ions cm-2 at room temperature. MeV H+ ions irradiation-induced local heat cause melting and fusion of NWs on intersecting points and eventually lead to reduce contact resistance between Ni-NWs. Electrical conductivity is enhanced with increase in beam fluence of H+ ions. These welded highly transparent and electrically conductive Ni-NWs meshes can be employed as transparent conducting electrodes in optoelectronic devices.

  6. Adipochemokines induced by ultraviolet irradiation contribute to impaired fat metabolism in subcutaneous fat cells.

    PubMed

    Kim, E J; Kim, Y K; Kim, S; Kim, J E; Tian, Y D; Doh, E J; Lee, D H; Chung, J H

    2018-02-01

    Adipose tissue is now appreciated as the pivotal regulator of metabolic and endocrine functions. Subcutaneous (SC) fat, in contrast to visceral fat, may protect against metabolic syndrome and systemic inflammation. We demonstrated that chronic as well as acute ultraviolet (UV) irradiation to the skin induces loss of underlying SC fat. UV-irradiated SC fat may produce chemokines or cytokines that modulate lipid homeostasis and secretion of adipokines. To elucidate UV-induced specific adipochemokines implicated in UV-induced modulation of SC fat. Primary cultured adipocytes were treated with conditioned medium from UV- or sham-irradiated skin cells. Young and older healthy participants provided SC fat from sun-exposed and sun-protected skin. Sun-protected skin from other participants was irradiated with UV. Differentially expressed adipochemokines were screened by cytokine array, and confirmed in vitro and in vivo. The functions of select adipochemokines involved in lipid metabolism were examined via short interfering RNA-mediated knockdown of cognate receptors. Specific adipochemokines, including C-X-C motif chemokine (CXCL) family members such as CXCL5/ENA-78, and C-C motif chemokine (CCL) family members such as CCL20/MIP-3α and CCL5/RANTES, were greatly induced in SC fat by UV exposure. They could impair triglyceride synthesis via downregulation of lipogenic enzymes and sterol regulatory element-binding protein-1 through their respective cognate receptors, CXC chemokine receptor type (CXC-R)2, C-C chemokine receptor type (CCR)-6, and CCR-5. In addition, UV irradiation induced infiltration of adipose tissue macrophages responsible for the secretion of several chemokines into SC fat. These UV-induced adipochemokines may be implicated in the reduction of lipogenesis in SC fat, leading to impairment of fat homeostasis and associated comorbidities such as obesity. © 2017 British Association of Dermatologists.

  7. Ageing and thermal recovery of paramagnetic centers induced by electron irradiation in yttria-stabilized zirconia

    NASA Astrophysics Data System (ADS)

    Costantini, J. M.; Beuneu, F.

    We have used electron spin resonance spectroscopy to study the defects induced in yttria-stabilized zirconia (YSZ) single crystals by 2.5-MeV electron irradiations. Two paramagnetic centers are produced: the first one with an axial <111> symmetry is similar to the trigonal Zr3+ electron center (T center) found after X-ray irradiation or thermo-chemical reduction, whereas the second one is a new oxygen hole center with an axial <100> symmetry different from the orthorhombic O- center induced by X-ray irradiation. At a fluence around 10(18) e/cm(2) , both centers are bleached out near 600 K, like the corresponding X-ray induced defects. At a fluence around 10(19) e/cm(2) , defects are much more stable, since complete thermal bleaching occurs near 1000 K. Accordingly, ageing of as-irradiated samples shows that high-dose defects at more stable than the low-dose ones.

  8. Evolution of irradiation-induced strain in an equiatomic NiFe alloy

    DOE PAGES

    Ullah, Mohammad W.; Zhang, Yanwen; Sellami, Neila; ...

    2017-07-10

    Here, we investigate the formation and accumulation of irradiation-induced atomic strain in an equiatomic NiFe concentrated solid-solution alloy using both atomistic simulations and x-ray diffraction (XRD) analysis of irradiated samples. Experimentally, the irradiations are performed using 1.5 MeV Ni ions to fluences ranging from 1 × 10 13 to 1 × 10 14 cm -2. The irradiation simulations are carried out by overlapping 5 keV Ni recoils cascades up to a total of 300 recoils. An increase of volumetric strain is observed at low dose, which is associated with production of point defects and small clusters. A relaxation of strainmore » occurs at higher doses, when large defect clusters, like dislocation loops, dominate.« less

  9. A Rare Case of Apical Root Resorption during Orthodontic Treatment of Patient with Multiple Aplasia.

    PubMed

    Agrawal, Chintan M; Mahida, Khyati; Agrawal, Charu C; Bothra, Jitendrakumar; Mashru, Ketan

    2015-07-01

    External apical root resorption is an adverse effect of orthodontic treatment. It reduces the length of root and breaks the integrity of teeth and dental arch. Orthodontics is the only dental specialty that clinically uses the inflammatory process to correct the mal-aligned teeth. Hence, it is necessary to know the risk factors of root resorption and do everything to reduce the rate of root resorption. Hence, all predisposing factors which are systemic as well as local should be considered before treatment begins. This case report describes the incidence of root resorption following orthodontic treatment and the teeth affected in the patient with multiple aplasia.

  10. Extract of Punica granatum inhibits skin photoaging induced by UVB irradiation.

    PubMed

    Park, Hye Min; Moon, Eunjung; Kim, Ae-Jung; Kim, Mi Hyun; Lee, Sanghee; Lee, Jung Bok; Park, Yong Kon; Jung, Hyuk-Sang; Kim, Yoon-Bum; Kim, Sun Yeou

    2010-03-01

    Punica granatum (pomegranate) is kind of a fruit consumed fresh or in beverage. It has been widely used in traditional medicine in various parts of the world. In this study, we examined the efficacy of a Punica granatum (PG) extract in protecting skin against UVB-induced damage using cultured human skin fibroblasts. A Korean red PG sample was used, and its effects classified according to if the PG source originated from the rind, seed and fruit. The polyphenol content of PG, which is known to prevent other adverse cutaneous effects of UV irradiation, was measured by GC-MS. The protective effects of PG on UVB-induced skin photoaging were examined by determining the level of procollagen type I and MMP-1 after UVB irradiation. Based on the GC-MS quantitative analysis, catechin, quercetin, kaempferol, and equol were the predominant compounds detected in PG. In the changes of expression of procollagen type I and MMP-1 in UV irradiated human skin fibroblasts treated PG, especially extract prepared from rind, the synthesis of collagen was increased and the expression of MMP-1 was decreased. The major polyphenols in PG, particularly catechin, play a significant role in its photoprotective effects on UVB-induced skin damage.

  11. Rescue Effects and Underlying Mechanisms of Intragland Shh Gene Delivery on Irradiation-Induced Hyposalivation.

    PubMed

    Hai, Bo; Zhao, Qingguo; Qin, Lizheng; Rangaraj, Dharanipathy; Gutti, Veera R; Liu, Fei

    2016-05-01

    Irreversible hypofunction of salivary glands is common in head and neck cancer survivors treated with radiotherapy and can only be temporarily relieved with current treatments. We found in an inducible sonic hedgehog (Shh) transgenic mouse model that transient activation of the Hedgehog pathway after irradiation rescued salivary gland function in males by preserving salivary stem/progenitor cells and parasympathetic innervation. To translate these findings into feasible clinical application, we evaluated the effects of Shh gene transfer to salivary glands of wild-type mice on irradiation-induced hyposalivation. Shh or control GFP gene was delivered by noninvasive retrograde ductal instillation of corresponding adenoviral vectors. In both male and female mice, Shh gene delivery efficiently activated Hedgehog/Gli signaling, and significantly improved stimulated saliva secretion and preserved saliva-producing acinar cells after irradiation. In addition to preserving parasympathetic innervation through induction of neurotrophic factors, Shh gene delivery also alleviated the irradiation damage of the microvasculature, likely via inducing angiogenic factors, but did not expand the progeny of cells responsive to Hedgehog/Gli signaling. These data indicate that transient activation of the Hedgehog pathway by gene delivery is promising to rescue salivary function after irradiation in both sexes, and the Hedgehog/Gli pathway may function mainly in cell nonautonomous manners to achieve the rescue effect.

  12. Electronic excitation induced modifications in elongated iron nanoparticle encapsulated multiwalled carbon nanotubes under ion irradiation

    NASA Astrophysics Data System (ADS)

    Saikiran, V.; Bazylewski, P.; Sameera, I.; Bhatia, Ravi; Pathak, A. P.; Prasad, V.; Chang, G. S.

    2018-05-01

    Multi-wall carbon nanotubes (MWCNT) filled with Fe nanorods were shown to have contracted and deformed under heavy ion irradiation. In this study, 120 MeV Ag and 80 MeV Ni ion irradiation was performed to study the deformation and defects induced in iron filled MWCNT under heavy ion irradiation. The structural modifications induced due to electronic excitation by ion irradiation were investigated employing high-resolution transmission electron microscopy, micro-Raman scattering experiments, and synchrotron-based X-ray absorption and emission spectroscopy. We understand that the ion irradiation causes modifications in the Fe nanorods which result in compressions and expansions of the nanotubes, and in turn leads to the buckling of MWCNT. The G band of the Raman spectra shifts slightly towards higher wavenumber and the shoulder G‧ band enhances with the increase of ion irradiation fluence, where the buckling wavelength depends on the radius 'r' of the nanotubes as exp[(r)0.5]. The intensity ratio of the D to G Raman modes initially decreases at the lowest fluence, and then it increases with the increase in ion fluence. The electron diffraction pattern and the high resolution images clearly show the presence of ion induced defects on the walls of the tube and encapsulated iron nanorods.

  13. About Assessment Criteria of Driver's Accidental Abilities

    ERIC Educational Resources Information Center

    Lobanova, Yuliya I.; Glushko, Kirill V.

    2016-01-01

    The article points at the importance of studying the human factor as a cause of accidents of drivers, especially in loosely structured traffic situations. The description of the experiment on the measurement of driver's accidental abilities is given. Under accidental ability is meant the capability to ensure the security of driving as a behavior…

  14. Accidental awareness during general anaesthesia - a narrative review.

    PubMed

    Tasbihgou, S R; Vogels, M F; Absalom, A R

    2018-01-01

    Unintended accidental awareness during general anaesthesia represents failure of successful anaesthesia, and so has been the subject of numerous studies during the past decades. As return to consciousness is both difficult to describe and identify, the reported incidence rates vary widely. Similarly, a wide range of techniques have been employed to identify cases of accidental awareness. Studies which have used the isolated forearm technique to identify responsiveness to command during intended anaesthesia have shown remarkably high incidences of awareness. For example, the ConsCIOUS-1 study showed an incidence of responsiveness around the time of laryngoscopy of 1:25. On the other hand, the 5th Royal College of Anaesthetists National Audit Project, which reported the largest ever cohort of patients who had experienced accidental awareness, used a system to identify patients who spontaneously self-reported accidental awareness. In this latter study, the incidence of accidental awareness was 1:19,600. In the recently published SNAP-1 observational study, in which structured postoperative interviews were performed, the incidence was 1:800. In almost all reported cases of intra-operative responsiveness, there was no subsequent explicit recall of intra-operative events. To date, there is no evidence that this occurrence has any psychological consequences. Among patients who experience accidental awareness and can later remember details of their experience, the consequences are better known. In particular, when awareness occurs in a patient who has been given neuromuscular blocking agents, it may result in serious sequelae such as symptoms of post-traumatic stress disorder and a permanent aversion to surgery and anaesthesia, and is feared by patients and anaesthetists. In this article, the published literature on the incidence, consequences and management of accidental awareness under general anaesthesia with subsequent recall will be reviewed. © 2017 The Association

  15. Factors perceived as being related to accidental falls by persons with multiple sclerosis.

    PubMed

    Nilsagård, Ylva; Denison, Eva; Gunnarsson, Lars-Gunnar; Boström, Katrin

    2009-01-01

    This study explores and describes factors that persons with multiple sclerosis (MS) perceive as being related to accidental falls. A qualitative content analysis with primarily deductive approach was conducted using the International Classification of Functioning, Disability and Health. Twelve persons with MS, and identified as fallers, were interviewed. Factors perceived to cause accidental falls that had not previously been targeted in MS populations in relation to falls were identified as divided attention, reduced muscular endurance, fatigue and heat sensitivity. Previously reported risk factors such as changed gait pattern, limited walking ability, impaired proprioception, vision and spasticity were supported. Activities involving walking, recreation and leisure, maintaining and changing body position, lifting or carrying, taking care of the home, washing the body, moving around, preparing meals and housekeeping were limited and considered to be risk activities. Supportive persons and assistive device reduced falls, and unsuitable physical environments and climate conditions induced falls. Several preventative strategies were described as partially compensating for the impairments, limitations and restrictions. Investigating accidental falls using the perspective of the patient gave important information about variables not earlier targeted in MS research.

  16. N-Acetyl-L-cysteine protects thyroid cells against DNA damage induced by external and internal irradiation.

    PubMed

    Kurashige, Tomomi; Shimamura, Mika; Nagayama, Yuji

    2017-11-01

    We evaluated the effect of the antioxidant N-acetyl-L-cysteine (NAC) on the levels of reactive oxygen species (ROS), DNA double strand breaks (DSB) and micronuclei (MN) induced by internal and external irradiation using a rat thyroid cell line PCCL3. In internal irradiation experiments, ROS and DSB levels increased immediately after 131 I addition and then gradually declined, resulting in very high levels of MN at 24 and 48 h. NAC administration both pre- and also post- 131 I addition suppressed ROS, DSB and MN. In external irradiation experiments with a low dose (0.5 Gy), ROS and DSB increased shortly and could be prevented by NAC administration pre-, but not post-irradiation. In contrast, external irradiation with a high dose (5 Gy) increased ROS and DSB in a bimodal way: ROS and DSB levels increased immediately after irradiation, quickly returned to the basal levels and gradually rose again after >24 h. The second phase was in parallel with an increase in 4-hydroxy-2-nonenal. The number of MN induced by the second wave of ROS/DSB elevations was much higher than that by the first peak. In this situation, NAC administered pre- and post-irradiation comparably suppressed MN induced by a delayed ROS elevation. In conclusion, a prolonged ROS increase during internal irradiation and a delayed ROS increase after external irradiation with a high dose caused serious DNA damage, which were efficiently prevented by NAC. Thus, NAC administration even both after internal or external irradiation prevents ROS increase and eventual DNA damage.

  17. Irreversible metal-insulator transition in thin film VO2 induced by soft X-ray irradiation

    NASA Astrophysics Data System (ADS)

    Singh, V. R.; Jovic, V.; Valmianski, I.; Ramirez, J. G.; Lamoureux, B.; Schuller, Ivan K.; Smith, K. E.

    2017-12-01

    In this study, we show the ability of soft x-ray irradiation to induce room temperature metal-insulator transitions (MITs) in VO2 thin films grown on R-plane sapphire. The ability of soft x-rays to induce MIT in VO2 thin films is confirmed by photoemission spectroscopy and soft x-ray spectroscopy measurements. When irradiation was discontinued, the systems do not return to the insulating phase. Analysis of valence band photoemission spectra revealed that the density of states (DOSs) of the V 3d band increased with irradiation time, while the DOS of the O 2p band decreased. We use these results to propose a model in which the MIT is driven by oxygen desorption from thin films during irradiation.

  18. Thyroid aplasia in male sibling of heterozygotic twins born to the hyperthyroid mother treated with propylthiouracil during pregnancy (case report).

    PubMed

    Almarzouki, A A

    2012-01-01

    A 30-year-old pregnant female was diagnosed to have thyrotoxicosis (TSH= 0.005 µU/ml) at 13th week of gestation. Propylthiouracil (PTU; 200 mg daily) was prescribed to her and four weekly follow ups by the endocrinologist and obstetrician were ensured. At each examination TSH, FT4 and FT3 levels were normal and she became symptom free. Repeated ultrasound examination throughout the pregnancy did not reveal any fetal abnormality. The lady normally delivered heterozygotic twins. Umbilical cord blood of the baby boy twin showed a high TSH (541 µU/ml; reference range 0.270 - 4.20 μU/ml). He was started on thyroxine therapy (50 µg once daily). Ultrasound reported the absence of the thyroid gland. One month later TSH was within normal range and thyroxine dose was adjusted to 25 µg once daily. Repeated ultrasound confirmed the absence of thyroid gland. TSH was repeatedly normal. The boy is currently doing well on thyroxine replacement therapy. The other non-identical twin was a healthy girl with normal thyroid function tests and always thereafter. This case report suggested that PTU could be a hazardous drug to the fetus, since the mother gave birth to a baby with thyroid aplasia. PTU, Thyroid aplasia, Thyrotoxicosis, TSH.

  19. Irradiation induces glioblastoma cell senescence and senescence-associated secretory phenotype.

    PubMed

    Jeon, Hee-Young; Kim, Jun-Kyum; Ham, Seok Won; Oh, Se-Yeong; Kim, Jaebong; Park, Jae-Bong; Lee, Jae-Yong; Kim, Sung-Chan; Kim, Hyunggee

    2016-05-01

    Glioblastoma multiforme (GBM) is one of the most aggressive and fatal primary brain tumors in humans. The standard therapy for the treatment of GBM is surgical resection, followed by radiotherapy and/or chemotherapy. However, the frequency of tumor recurrence in GBM patients is very high, and the survival rate remains poor. Delineating the mechanisms of GBM recurrence is essential for therapeutic advances. Here, we demonstrate that irradiation rendered 17-20 % of GBM cells dead, but resulted in 60-80 % of GBM cells growth-arrested with increases in senescence markers, such as senescence-associated beta-galactosidase-positive cells, H3K9me3-positive cells, and p53-p21(CIP1)-positive cells. Moreover, irradiation induced expression of senescence-associated secretory phenotype (SASP) mRNAs and NFκB transcriptional activity in GBM cells. Strikingly, compared to injection of non-irradiated GBM cells into immune-deficient mice, the co-injection of irradiated and non-irradiated GBM cells resulted in faster growth of tumors with the histological features of human GBM. Taken together, our findings suggest that the increases in senescent cells and SASP in GBM cells after irradiation is likely one of main reasons for tumor recurrence in post-radiotherapy GBM patients.

  20. Scaling and Multifractality in Road Accidental Distances

    NASA Astrophysics Data System (ADS)

    Qiu, Tian; Wan, Chi; Zou, Xiang-Xiang; Wang, Xiao-Fan

    Accidental distance dynamics is investigated, based on the road accidental data of the Great Britain. The distance distribution of all the districts as an ensemble presents a power law tail, which is different from that of the individual district. A universal distribution is found for different districts, by rescaling the distribution functions of individual districts, which can be well fitted by the Weibull distribution. The male and female drivers behave similarly in the distance distribution. The multifractal characteristic is further studied for the individual district and all the districts as an ensemble, and different behaviors are also revealed between them. The accidental distances of the individual district show a weak multifractality, whereas of all the districts present a strong multifractality when taking them as an ensemble.

  1. Study of irradiation induced surface pattern and structural changes in Inconel 718 alloy

    NASA Astrophysics Data System (ADS)

    Wan, Hao; Si, Naichao; Zhao, Zhenjiang; Wang, Jian; Zhang, Yifei

    2018-05-01

    Helium ions irradiation induced surface pattern and structural changes of Inconel 718 alloy were studied with the combined utilization of atomic force microscopy (AFM), x-ray diffraction (XRD) and transmission electron microscopy (TEM). In addition, SRIM-2013 software was used to calculate the sputtering yield and detailed collision events. The result shows that, irradiation dose play an important role in altering the pattern of the surface. Enhanced irradiation aggravated the surface etching and increased the surface roughness. In ion irradiated layer, large amount of interstitials, vacancies and defect sinks were produced. Moreover, in samples with increasing dose irradiation, the dependence of interplanar spacing variation due to point defects clustering on sink density was discussed.

  2. Course Management Systems for Learning: Beyond Accidental Pedagogy

    ERIC Educational Resources Information Center

    McGee, Patricia; Carmean, Colleen; Jafari, Ali

    2005-01-01

    "Course Management Systems for Learning: Beyond Accidental Pedagogy" is a comprehensive overview of standards, practices and possibilities of course management systems in higher education. "Course Management Systems for Learning: Beyond Accidental Pedagogy" focuses on what the current knowledge is (in best practices, research, standards and…

  3. Irradiation induced kyphosis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Riseborough, E.J.

    1977-10-01

    Eighty-one patients with Wilms tumor treated by irradiation and chemotherapy were studied. Despite the fact that multiple portals for irradiation were used, each crossing the midline, the amount of irradiation delivered to different parts of the vertebral body varied and it was this variation in delivered dose which produced axial skeletal deformities in 70% of the patients. Of the 57 patients with these deformities, 32 had scoliosis, 22 kyphoscoliosis and 3 patients pure kyphosis; 12 patients had a kyphotic deformity of over 25 degrees, 7 patients requiring surgical correction. A high incidence of pseudarthrosis following posterior fusion has led tomore » the preference of a 2-stage procedure, anterior interbody fusion followed by a posterior fusion with Harrington rods after 2 weeks of correction in halo femoral traction.« less

  4. Fundamental Studies of Irradiation-Induced Modifications in Microstructural Evolution and Mechanical Properties of Advanced Alloys

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stubbins, James; Heuser, Brent; Hosemann, Peter

    This final technical report summarizes the research performed during October 2014 and December 2017, with a focus on investigating the radiation-induced microstructural and mechanical property modifications in optimized advanced alloys for sodium-cooled fast reactor (SFR) structural applications. To accomplish these objectives, the radiation responses of several different advanced alloys, including austenitic steel Alloy 709 (A709) and 316H, and ferritic/ martensitic Fe–9Cr steels T91 and G92, were investigated using a combination of microstructure characterizations and nanoindentation measurements. Different types of irradiation, including ex situ bulk ion irradiation and in situ transmission electron microscopy (TEM) ion irradiation, were employed in this study.more » Radiation-induced dislocations, precipitates, and voids were characterized by TEM. Scanning transmission electron microscopy with energy dispersive X-ray spectroscopy (STEM-EDS) and/or atom probe tomography (APT) were used to study radiation-induced segregation and precipitation. Nanoindentation was used for hardness measurements to study irradiation hardening. Austenitic A709 and 316H was bulk-irradiated by 3.5 MeV Fe ++ ions to up to 150 peak dpa at 400, 500, and 600°. Compared to neutron-irradiated stainless steel (SS) 316, the Frank loop density of ion-irradiated A709 shows similar dose dependence at 400°, but very different temperature dependence. Due to the noticeable difference in the initial microstructure of A709 and 316H, no systematic comparison on the Frank loops in A709 vs 316H was made. It would be helpful that future ion irradiation study on 316 stainless steel could be conducted to directly compare the temperature dependence of Frank loop density in ion-irradiated 316 SS with that in neutron-irradiated 316 SS. In addition, future neutron irradiation on A709 at 400–600° at relative high dose (≥10 dpa) can be carried out to compare with ion-irradiated A709. The radiation-induced

  5. A Reevaluation of X-Irradiation Induced Phocomelia and Proximodistal Limb Patterning

    PubMed Central

    Galloway, Jenna L.; Delgado, Irene; Ros, Maria A.; Tabin, Clifford J.

    2009-01-01

    Phocomelia is a devastating, rare congenital limb malformation in which the long bones are shorter than normal, with the upper portion of the limb being most severely affected. In extreme cases, the hands or fingers are attached directly to the shoulder and the most proximal elements (those closest to the shoulder) are entirely missing. This disorder, previously known in both autosomal recessive and sporadic forms, showed a dramatic increase in incidence in the early 1960’s due to the tragic toxicological effects of the drug thalidomide, which had been prescribed as a mild sedative1, 2. This human birth defect is mimicked in developing chick limb buds exposed to X-irradiation3-5. Both X-irradiation5 and thalidomide-induced phocomelia5, 6 have been interpreted as patterning defects in the context of the Progress Zone Model, which states that a cell’s proximodistal (PD) identity is determined by the length of time spent in a distal limb region termed the “Progress Zone” 7. Indeed, studies of X-irradiation induced phocomelia have served as one of the two major experimental lines of evidence supporting the validity of the Progress Zone Model. Here, using a combination of molecular analysis and lineage tracing, we show that X-irradiation-induced phocomelia is fundamentally not a patterning defect, but rather results from a time-dependent loss of skeletal progenitors. As skeletal condensation proceeds from the shoulder to fingers (in a proximal to distal direction), the proximal elements are differentially affected in limb buds exposed to radiation at early stages. This conclusion changes the framework for considering the effect of thalidomide and other forms of phocomelia, suggesting the possibility that the etiology lies not in a defect in the patterning process, but rather in progenitor cell survival and differentiation. Moreover, molecular evidence that PD patterning is unaffected following X-irradiation does not support the predictions of the Progress Zone

  6. Laser-induced retinal injury thresholds: variation with retinal irradiated area

    NASA Astrophysics Data System (ADS)

    Lund, David J.; Schulmeister, Karl; Seiser, Bernhard; Edthofer, Florian

    2005-04-01

    The retinal injury threshold for exposure to a laser source varies as a function of the irradiated area on the retina. Currently accepted guidelines for the safe use of lasers provide that the MPE will increase as the diameter of the irradiated area for retinal diameters between 25 mm and 1700 mm, based on the ED50 data available in the late 1970s. Recent studies by Zuclich and Lund produced data showing that the ED50 for ns-duration exposures at 532 nm and ms duration exposures at 590 nm varied as the square of the diameter of the irradiated area on the retina. This paper will discuss efforts to resolve the disagreement between the new data and the earlier data though an analysis of all accessible data relating the retinal injury threshold to the diameter of the incident beam on the retina and through simulations using computer models of laser-induced injury. The results show that the retinal radiant exposure required to produce retinal injury is a function of both exposure duration and retinal irradiance diameter and that the current guidelines for irradiance diameter dependence do not accurately reflect the variation of the threshold data.

  7. Evaluation of radio-protective effect of melatonin on whole body irradiation induced liver tissue damage.

    PubMed

    Shirazi, Alireza; Mihandoost, Ehsan; Ghobadi, Ghazale; Mohseni, Mehran; Ghazi-Khansari, Mahmoud

    2013-01-01

    Ionizing radiation interacts with biological systems to induce excessive fluxes of free radicals that attack various cellular components. Melatonin has been shown to be a direct free radical scavenger and indirect antioxidant via its stimulatory actions on the antioxidant system.The aim of this study was to evaluate the antioxidant role of melatonin against radiation-induced oxidative injury to the rat liver after whole body irradiation. In this experimental study,thirty-two rats were divided into four groups. Group 1 was the control group, group 2 only received melatonin (30 mg/kg on the first day and 30 mg/kg on the following days), group 3 only received whole body gamma irradiation of 10 Gy, and group 4 received 30 mg/kg melatonin 30 minutes prior to radiation plus whole body irradiation of 10 Gy plus 30 mg/kg melatonin daily through intraperitoneal (IP) injection for three days after irradiation. Three days after irradiation, all rats were sacrificed and their livers were excised to measure the biochemical parameters malondialdehyde (MDA) and glutathione (GSH). Each data point represents mean ± standard error on the mean (SEM) of at least eight animals per group. A one-way analysis of variance (ANOVA) was performed to compare different groups, followed by Tukey's multiple comparison tests (p<0.05). The results demonstrated that whole body irradiation induced liver tissue damage by increasing MDA levels and decreasing GSH levels. Hepatic MDA levels in irradiated rats that were treated with melatonin (30 mg/kg) were significantly decreased, while GSH levels were significantly increased, when compared to either of the control groups or the melatonin only group. The data suggest that administration of melatonin before and after irradiation may reduce liver damage caused by gamma irradiation.

  8. The Accidental Transgressor: Morally Relevant Theory of Mind

    PubMed Central

    Killen, Melanie; Mulvey, Kelly Lynn; Richardson, Cameron; Jampol, Noah

    2014-01-01

    To test young children’s false belief theory of mind in a morally relevant context, two experiments were conducted. In Experiment 1, children (N = 162) at 3.5, 5.5, and 7.5 years of age were administered 3 tasks: prototypic moral transgression task, false belief theory of mind task (ToM), and an “accidental transgressor” task, which measured a morally relevant false belief theory of mind (MoToM). Children who did not pass false belief ToM were more likely to attribute negative intentions to an accidental transgressor than children who passed false belief ToM, and to use moral reasons when blaming the accidental transgressor. In Experiment 2, children (N = 46) who did not pass false belief ToM viewed it as more acceptable to punish the accidental transgressor than did participants who passed false belief ToM. Findings are discussed in light of research on the emergence of moral judgment and theory of mind. PMID:21377148

  9. Excimer UV lamp irradiation induced grafting on synthetic polymers

    NASA Astrophysics Data System (ADS)

    Praschak, D.; Bahners, T.; Schollmeyer, E.

    Surface modifications on polyethyleneterephthalate (PET) films following excimer UV lamp irradiation induced grafting were studied. Characteristics of the modifications depending on the conditions during the irradiation were analysed using contact-angle measurements, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). Depending on the conditions during the irradiation different surface modifications were obtained, which can generally be classified regarding the hydrophilic or hydrophobic characteristics of the resulting surface. It is shown that not every substance that meets the general demands will be grafted on synthetic polymers using excimer UV radiation. Examples of agents that can simply be grafted onto polymer surfaces and those that undergo further crosslinking, building up thin films are listed. Agents used for grafting on polymers are 1,5-hexadiene, perfluoro-4-methyl-pent-2-ene, polyethyleneglycol 200, monosilane and polyethylene. The transferability of the effects achieved to substrates such as polyparaphenylene terephthalamide or polymetaphenylene isophthalamide is shown.

  10. Induced parthenogenesis by gamma-irradiated pollen in loquat for haploid production.

    PubMed

    Blasco, Manuel; Badenes, María Luisa; Del Mar Naval, María

    2016-09-01

    Successful haploid induction in loquat ( Eriobotrya japonica (Thunb.) Lindl.) through in situ-induced parthenogenesis with gamma-ray irradiated pollen has been achieved. Female flowers of cultivar 'Algerie' were pollinated using pollen of cultivars 'Changhong-3', 'Cox' and 'Saval Brasil' irradiated with two doses of gamma rays, 150 and 300 Gy. The fruits were harvested 90, 105 and 120 days after pollination (dap). Four haploid plants were obtained from 'Algerie' pollinated with 300-Gy-treated pollen of 'Saval Brasil' from fruits harvested 105 dap. Haploidy was confirmed by flow cytometry and chromosome count. The haploids showed a very weak development compared to the diploid plants. This result suggests that irradiated pollen can be used to obtain parthenogenetic haploids.

  11. Reactive oxygen species production in mitochondria of human gingival fibroblast induced by blue light irradiation.

    PubMed

    Yoshida, Ayaka; Yoshino, Fumihiko; Makita, Tetsuya; Maehata, Yojiro; Higashi, Kazuyoshi; Miyamoto, Chihiro; Wada-Takahashi, Satoko; Takahashi, Shun-suke; Takahashi, Osamu; Lee, Masaichi Chang-il

    2013-12-05

    In recent years, it has become well known that the production of reactive oxygen species (ROS) induced by blue-light irradiation causes adverse effects of photo-aging, such as age-related macular degeneration of the retina. Thus, orange-tinted glasses are used to protect the retina during dental treatment involving blue-light irradiation (e.g., dental resin restorations or tooth bleaching treatments). However, there are few studies examining the effects of blue-light irradiation on oral tissue. For the first time, we report that blue-light irradiation by quartz tungsten halogen lamp (QTH) or light-emitting diode (LED) decreased cell proliferation activity of human gingival fibroblasts (HGFs) in a time-dependent manner (<5 min). Additionally, in a morphological study, the cytotoxic effect was observed in the cell organelles, especially the mitochondria. Furthermore, ROS generation induced by the blue-light irradiation was detected in mitochondria of HGFs using fluorimetry. In all analyses, the cytotoxicity was significantly higher after LED irradiation compared with cytotoxicity after QTH irradiation. These results suggest that blue light irradiation, especially by LED light sources used in dental aesthetic treatment, might have adverse effects on human gingival tissue. Hence, this necessitates the development of new dental aesthetic treatment methods and/or techniques to protect HGFs from blue light irradiation during dental therapy. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Treatment of aggressive multiple myeloma by high-dose chemotherapy and total body irradiation followed by blood stem cells autologous graft

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fermand, J.P.; Levy, Y.; Gerota, J.

    1989-01-01

    Eight patients with stage III aggressive multiple myeloma, refractory to current chemotherapy in six cases, were treated by high-dose chemotherapy (nitrosourea, etoposide, and melphalan) (HDC) and total body irradiation (TBI), followed by autografting with blood stem cells. These cells were previously collected by leukapheresis performed during hematologic recovery following cytotoxic drug-induced bone marrow aplasia. Seven patients were alive 9 to 17 months after HDC-TBI and graft. One died at day 40 from cerebral bleeding. All living patients achieved a 90% or greater reduction in tumor mass. In two cases, a complete remission (CR) has persisted at a follow-up of 15more » and 16 months. Three patients have been well and off therapy with stable minimal residual disease (RD) since 10, 11, and 17 months, respectively. A patient in apparent CR and another with RD have relapsed 9 to 12 months posttreatment. Autologous blood-derived hematopoietic stem cells induced successful and sustained engraftment in all living patients. These results, although still preliminary, indicate that HDC and TBI, followed by blood stem cells autograft, which has both practical and theoretical interest over allogeneic or autologous bone marrow transplantation, deserve consideration in selected patients with multiple myeloma.« less

  13. Irradiated esophageal cells are protected from radiation-induced recombination by MnSOD gene therapy.

    PubMed

    Niu, Yunyun; Wang, Hong; Wiktor-Brown, Dominika; Rugo, Rebecca; Shen, Hongmei; Huq, M Saiful; Engelward, Bevin; Epperly, Michael; Greenberger, Joel S

    2010-04-01

    Radiation-induced DNA damage is a precursor to mutagenesis and cytotoxicity. During radiotherapy, exposure of healthy tissues can lead to severe side effects. We explored the potential of mitochondrial SOD (MnSOD) gene therapy to protect esophageal, pancreatic and bone marrow cells from radiation-induced genomic instability. Specifically, we measured the frequency of homologous recombination (HR) at an integrated transgene in the Fluorescent Yellow Direct Repeat (FYDR) mice, in which an HR event can give rise to a fluorescent signal. Mitochondrial SOD plasmid/liposome complex (MnSOD-PL) was administered to esophageal cells 24 h prior to 29 Gy upper-body irradiation. Single cell suspensions from FYDR, positive control FYDR-REC, and negative control C57BL/6NHsd (wild-type) mouse esophagus, pancreas and bone marrow were evaluated by flow cytometry. Radiation induced a statistically significant increase in HR 7 days after irradiation compared to unirradiated FYDR mice. MnSOD-PL significantly reduced the induction of HR by radiation at day 7 and also reduced the level of HR in the pancreas. Irradiation of the femur and tibial marrow with 8 Gy also induced a significant increase in HR at 7 days. Radioprotection by intraesophageal administration of MnSOD-PL was correlated with a reduced level of radiation-induced HR in esophageal cells. These results demonstrate the efficacy of MnSOD-PL for suppressing radiation-induced HR in vivo.

  14. Local brain heavy ion irradiation induced Immunosuppression

    NASA Astrophysics Data System (ADS)

    Lei, Runhong; Deng, Yulin; Huiyang Zhu, Bitlife.; Zhao, Tuo; Wang, Hailong; Yu, Yingqi; Ma, Hong; Wang, Xiao; Zhuang, Fengyuan; Qing, Hong

    Purpose: To investigate the long term effect of acute local brain heavy ion irradiation on the peripheral immune system in rat model. Methodology: Only the brain of adult male Wistar rats were radiated by heavy ions at the dose of 15 Gy. One, two and three months after irradiation, thymus and spleen were analyzed by four ways. Tunel assay was performed to evaluate the percentage of apoptotic cells in thymus and spleen, level of Inflammatory cytokines (IL-2, IL-6, SSAO, and TNF-α) was detected by ELISA assay, the differentiation of thymus T lymphocyte subsets were measured by flow cytometry and the relative expression levels of genes related to thymus immune cell development were measured by using quantitative real-time PCR. Results: Thymus and spleen showed significant atrophy from one month to three months after irradiation. A high level of apoptosis in thymus and spleen were obtained and the latter was more vulnerable, also, high level of inflammatory cytokines were found. Genes (c-kit, Rag1, Rag2 and Sca1) related to thymus lymphocytes’ development were down-regulated. Conclusion: Local area radiation in the rat brain would cause the immunosuppression, especially, the losing of cell-mediated immune functions. In this model, radiation caused inflammation and then induced apoptosis of cells in the immune organs, which contributed to immunosuppression.

  15. Low-energy N+ ion irradiation induced synthesis of nitrogenous compound from solid organic sodium salts

    NASA Astrophysics Data System (ADS)

    Wang, Xiangqin; Yu, Zengliang

    2003-08-01

    In this paper, samples of solid organic sodium salts (sodium formate, sodium acetate and sodium benzoate) were irradiated by low-energy N+ ions. The induced damage was detected by infrared (FT-IR). It is shown that a new cyano group (-CN) and amino group (-NH2) were formed in the irradiated sodium carbroxylic sample with N+ ion irradiation. The experimental results examined the effect of N+ ion irradiation by reacting with sodium salt molecules, and presented a new way for the synthesis of nitrogenous compound by low-energy ion irradiation.

  16. EFFICIENCY OF BORAGE SEEDS OIL AGAINST GAMMA IRRADIATION-INDUCED HEPATOTOXICITY IN MALE RATS: POSSIBLE ANTIOXIDANT ACTIVITY.

    PubMed

    Khattab, Hala A H; Abdallah, Inas Z A; Yousef, Fatimah M; Huwait, Etimad A

    2017-01-01

    Borage ( Borago officinal L.) is an annual herbaceous plant of great interest because its oil contains a high percentage of γ-linolenic acid (GLA). The present work was carried out to detect fatty acids composition of the oil extracted from borage seeds (BO) and its potential effectiveness against γ-irradiation- induced hepatotoxicity in male rats. GC-MS analysis of fatty acids methyl esters of BO was performed to identify fatty acids composition. Sixty rats were divided into five groups (12 rats each): Control, irradiated; rats were exposed to (6.5 Gy) of whole body γ-radiation, BO (50 mg/kg b.wt), irradiated BO post-treated and irradiated BO prepost-treated. Six rats from each group were sacrificed at two time intervals 7 and 15 days post-irradiation. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyl transferase (GGT) levels, lipids profile, as well as serum and hepatic reduced glutathione (GSH) and lipid peroxide (malondialdehyde) (MDA) levels were assessed. Histopathological examination of liver sections were also carried out. The results showed that the high contents of BO extracted by cold pressing, were linoleic acid (34.23%) and GLA (24.79%). Also, oral administration of BO significantly improved serum levels of liver enzymes, lipids profile, as well as serum and hepatic GSH and MDA levels (p<0.001) as compared with irradiated rats after 15 days post irradiation. Moreover, it exerted marked amelioration against irradiation-induced histopathological changes in liver tissues. The improvement was more pronounced in irradiated BO prepost-treated group than irradiated BO post-treated. BO has a beneficial role in reducing hepatotoxicity and oxidative stress induced by radiation exposure. Therefore, BO may be used as a beneficial supplement for patients during radiotherapy treatment.

  17. Origin of MeV ion irradiation-induced stress changes in SiO2

    NASA Astrophysics Data System (ADS)

    Brongersma, M. L.; Snoeks, E.; van Dillen, T.; Polman, A.

    2000-07-01

    The 4 MeV Xe ion irradiation of a thin thermally grown SiO2 film on a Si substrate leads to four different effects in which each manifests itself by a characteristic change in the mechanical stress state of the film: densification, ascribed to a beam-induced structural change in the silica network; stress relaxation by radiation-enhanced plastic flow; anisotropic expansion and stress generation; and transient stress relaxation ascribed to the annealing of point defects. Using sensitive wafer-curvature measurements, in situ measurements of the in-plane mechanical stress were made during and after ion irradiation at various temperatures in the range from 95 to 575 K, in order to study the magnitude of these effects, the mechanism behind them, as well as their interplay. It is found that the structural transformation leads to a state with an equilibrium density that is 1.7%-3.2% higher than the initial state, depending on the irradiation temperature. Due to the constraint imposed by the substrate, this transformation causes a tensile in-plane stress in the oxide film. This stress is relaxed by plastic flow, leading to densification of the film. The anisotropic strain-generation rate decreases linearly with temperature from (2.5±0.4)×10-17cm2/ion at 95 K to (-0.9±0.7)×10-17 cm2/ion at 575 K. The spectrum of irradiation-induced point defects, measured from the stress change after the ion beam was switched off, peaks below 0.23 eV and extends up to 0.80 eV. All four irradiation-induced effects can be described using a thermal spike model.

  18. Detection of radiation-induced hydrocarbons in baked sponged cake prepared with irradiated liquid egg

    NASA Astrophysics Data System (ADS)

    Schulzki, G.; Spiegelberg, A.; Bögl, K. W.; Schreiber, G. A.

    1995-02-01

    For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of this fast and efficient technique is demonstrated by the example of detection of radiation-induced HC in fat isolated from baked sponge cake which had been prepared with irradiated liquid egg.

  19. Induced parthenogenesis by gamma-irradiated pollen in loquat for haploid production

    PubMed Central

    Blasco, Manuel; Badenes, María Luisa; del Mar Naval, María

    2016-01-01

    Successful haploid induction in loquat (Eriobotrya japonica (Thunb.) Lindl.) through in situ-induced parthenogenesis with gamma-ray irradiated pollen has been achieved. Female flowers of cultivar ‘Algerie’ were pollinated using pollen of cultivars ‘Changhong-3’, ‘Cox’ and ‘Saval Brasil’ irradiated with two doses of gamma rays, 150 and 300 Gy. The fruits were harvested 90, 105 and 120 days after pollination (dap). Four haploid plants were obtained from ‘Algerie’ pollinated with 300-Gy-treated pollen of ‘Saval Brasil’ from fruits harvested 105 dap. Haploidy was confirmed by flow cytometry and chromosome count. The haploids showed a very weak development compared to the diploid plants. This result suggests that irradiated pollen can be used to obtain parthenogenetic haploids. PMID:27795686

  20. A Model for Microcontroller Functionality Upset Induced by External Pulsed Electromagnetic Irradiation

    DTIC Science & Technology

    2016-11-21

    AFRL-RD-PS- AFRL-RD-PS- TN-2016-0003 TN-2016-0003 A Model for Microcontroller Functionality Upset Induced by External Pulsed Electromagnetic ...External Pulsed Electromagnetic Irradiation 5a. CONTRACT NUMBER FA9451-15-C-0004 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6 . AUTHOR(S) David...microcontroller (µC) subjected to external irradiation by a narrowband electromagnetic (EM) pulse. In our model, the state of a µC is completely specified by

  1. Damage induced in garnets by heavy ion irradiations: a study by optical spectroscopies

    NASA Astrophysics Data System (ADS)

    Costantini, Jean-Marc; Miro, Sandrine; Lelong, Gérald; Guillaumet, Maxime; Toulemonde, Marcel

    2018-02-01

    The damage induced by heavy-ion irradiation has been studied in yttrium iron garnet (Y3Fe5O12 or YIG) films, doped with Ca, Tb and Tm, grown by liquid-phase epitaxy on gadolinium gallium garnet (Gd3Ga5O12 or GGG) substrates. Irradiations of doped-YIG epitaxial films and GGG substrates with 36-MeV 183W and 12-MeV 197Au ions were applied for fluences between 1 × 1013 and 3 × 1015 cm-2 near room temperature. The radiation damage was monitored by micro-Raman spectroscopy and UV-visible optical absorption spectroscopy. Raman spectra revealed that amorphisation was achieved in YIG for both ions, whereas a high lattice disorder was induced in GGG without reaching amorphisation for the Au ion irradiation. Raman spectra also showed that a major damage of the tetrahedral sites was induced in GGG, as previously found for YIG. It is concluded that with such ions reaching the stopping power threshold of track formation in YIG and GGG the observed rate of amorphisation may result from a combination of electronic and nuclear energy losses as calculated using the unified thermal spike model.

  2. Pathway-specific effect of caffeine on protection against UV irradiation-induced apoptosis in corneal epithelial cells.

    PubMed

    Wang, Ling; Lu, Luo

    2007-02-01

    To define the role of molecular interaction between the UV-induced JNK (c-Jun N-terminal kinase) cascade and corneal epithelial cell apoptosis and protection against apoptosis by caffeine. Rabbit and human corneal epithelial cells were cultured in DMEM/F12 medium containing 10% FBS and 5 microg/mL insulin at 37 degrees C in 5% CO(2). DNA fragmentation and ethidium bromide/acridine orange (EB/AO) nuclear staining were performed to detect cell death. Western blot, immunoprecipitation, and kinase assays were used to measure UV-induced mitogen-activated protein (MAP) kinase activity. UV irradiation-induced apoptosis through apoptosis signal-regulating kinase 1 (ASK1) and MAKK4 (SEK1) upstream from JNK was caffeine sensitive. Caffeine (1,3,7-trimethylxanthine), an agent that is one of the most popular additions to food consumed in the world and a potential enhancer of chemotherapy, effectively protected corneal epithelial cells against apoptosis by its specific effect on the JNK cascade. Theophylline (1,3-dimethylxanthine) exhibited an effect similar to that of caffeine on prevention of UV irradiation-induced apoptosis. However, alterations of either intracellular cAMP or Ca(2+) levels did not alter the effect of caffeine on the JNK signaling pathway. In addition, the blockade of PI3K-like kinases by wortmannin had no impact on the protective effect of caffeine against UV irradiation-induced apoptosis, suggesting that the protective effect of caffeine acts through a specific mechanism involving UV irradiation-induced activation of ASK1 and SEK1. In contrast, caffeine had no effects on melphalan-, hyperosmotic stress-, or IL-1beta-induced activation of the JNK signaling pathway in these cells. UV irradiation stress-induced activation of the ASK1-SEK1-JNK signaling pathway leading to apoptosis is a caffeine-sensitive process, and caffeine, as a multifunctional agent in cells, can specifically interact with the pathway to protect against apoptosis.

  3. Accidental poisoning with "Chinese chalk".

    PubMed

    Martínez-Navarrete, Juan; Loria-Castellanos, Jorge; Nava-Ocampo, Alejandro A

    2008-04-01

    We present a 1.5-year old, 11 kg, female infant with a history of bronchial hyper-responsiveness who accidentally ingested half of a "Chinese chalk". A day later, the infant showed vomiting, cough, fever, drowsiness, and irritability and her clinical conditions progressively worsened. She was admitted to the emergency department with cough, respiratory distress, and hepatomegaly. It has been reported that the chalk may contain deltamethrin and cypermethrin. The patient was successfully treated with supportive therapy. This report identifies "Chinese chalk" as a potential source of accidental poisoning in children and should be considered as part of the differential diagnoses in the emergency rooms since poisoning with these compounds may be misdiagnosed as organophosphate poisoning due to the presentation of similar symptoms.

  4. Mitotic UV Irradiation Induces a DNA Replication-Licensing Defect that Potentiates G1 Arrest Response

    PubMed Central

    Morino, Masayuki; Nukina, Kohei; Sakaguchi, Hiroki; Maeda, Takeshi; Takahara, Michiyo; Shiomi, Yasushi; Nishitani, Hideo

    2015-01-01

    Cdt1 begins to accumulate in M phase and has a key role in establishing replication licensing at the end of mitosis or in early G1 phase. Treatments that damage the DNA of cells, such as UV irradiation, induce Cdt1 degradation through PCNA-dependent CRL4-Cdt2 ubiquitin ligase. How Cdt1 degradation is linked to cell cycle progression, however, remains unclear. In G1 phase, when licensing is established, UV irradiation leads to Cdt1 degradation, but has little effect on the licensing state. In M phase, however, UV irradiation does not induce Cdt1 degradation. When mitotic UV-irradiated cells were released into G1 phase, Cdt1 was degraded before licensing was established. Thus, these cells exhibited both defective licensing and G1 cell cycle arrest. The frequency of G1 arrest increased in cells expressing extra copies of Cdt2, and thus in cells in which Cdt1 degradation was enhanced, whereas the frequency of G1 arrest was reduced in cell expressing an extra copy of Cdt1. The G1 arrest response of cells irradiated in mitosis was important for cell survival by preventing the induction of apoptosis. Based on these observations, we propose that mammalian cells have a DNA replication-licensing checkpoint response to DNA damage induced during mitosis. PMID:25798850

  5. Molecular imaging of low-power laser irradiation induced cell proliferation

    NASA Astrophysics Data System (ADS)

    Gao, Xuejuan; Wang, Fang; Da, Xing

    2006-02-01

    Low-power laser irradiation (LPLI) has been shown to promote cell proliferation in various cell types, yet the mechanism of which has not been fully clarified. Studying the signaling pathways involved in the laser irradiation is important for understanding these processes. The Ras/Raf/MEK/ERK (extracellular-signal-regulated kinase) signaling pathway is a network that governs proliferation, differentiation and cell survival. Recent studies suggest that Ras/Raf signaling pathway is involved in the LPLI-induced cell proliferation. Protein kinase Cs (PKCs) have been recently presumed to be involved in the regulation of cell proliferation induced by LPLI. In present study, to monitor the direct interaction between Ras and Raf and PKCs activation after LPLI treatment in living cells in real time, Raichu-Ras reporter and C kinase activity reporter (CKAR) were utilized, both of which were constructed based on fluorescence resonance energy transfer (FRET) technique. Our results show that the direct interaction between Ras and Raf is monitored during cell proliferation induced by LPLI (0.8 J/cm2) in serum-starved human lung adenocarcinoma cells (ASTC-a-1) expressing Raichu-Ras reporter using FRET imaging on laser scanning confocal microscope, and that the increasing dynamics of PKCs activity is also monitored during cell proliferation induced by LPLI (0.8 J/cm2) in serum-starved ASTC-a-1 cells expressing CKAR reporter using the similar way. Taken together, LPLI induces the ASTC-a-1 cell proliferation by activated Ras directly interacting with Raf and by specifically activating PKCs.

  6. Transition from Irradiation-Induced Amorphization to Crystallization in Nanocrystalline Silicon Carbide

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jiang, Weilin; Jiao, Liang; Wang, Haiyan

    2011-12-01

    Response to irradiation of nanocrystalline 3C-SiC is studied using 2 MeV Au+ ions near the critical temperature for amorphization and is compared to the behavior of its monocrystalline counterpart under the identical irradiation conditions. The irradiated samples have been characterized using in-situ ion channeling, ex-situ x-ray diffraction, and helium ion microscopy. Compared to monocrystalline 3C-SiC, a faster amorphization process in the nanocrystalline material (average grain size = 3.3 nm) is observed at 500 K. However, the nanograin grows with increasing ion fluence at 550 K and the grain size tends to saturate at high fluences. The striking contrast demonstrates amore » sharp transition from irradiation-induced interface-driven amorphization at 500 K to crystallization at 550 K. The results could show potential impacts of nanocrystalline SiC on nuclear fuel cladding and structural components of next-generation nuclear energy systems.« less

  7. Accidental and experimentally induced 5-fluorouracil toxicity in dogs.

    PubMed

    Sayre, Rebecca S; Barr, James W; Bailey, E Murl

    2012-10-01

    To summarize the literature involving 5-fluorouracil (5-FU) toxicosis in dogs. 5-Fluorouracil's mechanism of action revolves around the metabolism of 5-FU into fluorouridine triphosphate which then interferes with RNA synthesis and function as well as the inhibition of thymidylate synthase which ultimately impairs DNA stability. Toxicity of 5-FU is the most pronounced on rapidly dividing cells. Toxicity manifests itself mainly in the neurologic, gastrointestinal, respiratory, or hematopoietic systems. History of accidental exposure to 5-FU-containing products. Therapy for 5-FU toxicosis involves typical decontamination procedures and symptomatic therapy for the subsequent toxicity. Seizure control and treatment of the severe gastrointestinal signs that follow are the primary goals in the acute setting. As the disease progresses, management of the sequelae to bone marrow suppression and pulmonary complications are essential. The prognosis for dogs with ingestion of 5-FU is dependent on the amount consumed, with severe intoxication carrying a poor prognosis. Toxic doses can be as little as 5 mg/kg, and doses ≥40 mg/kg are reported to be uniformly fatal. © Veterinary Emergency and Critical Care Society 2012.

  8. Accidental Nuclear War: The Growing Peril. Part I [and] Part II.

    ERIC Educational Resources Information Center

    Newcombe, Alan, Ed.

    1984-01-01

    Two volumes designed to increase awareness of accidental nuclear war dangers are presented. The first of 5 sections in volume I proposes that although accidental war is preventable, the current arms race and secrecy about accidents and false alarms increase the possibility of an accidental war. Section 2 posits that decreased decision-making time…

  9. Advancement Is Seldom Accidental.

    ERIC Educational Resources Information Center

    Frantzreb, Arthur C.

    1981-01-01

    Success in college goals and programs for institutional advancement is seldom accidental: success in philanthropic support is seen as 90 percent planning and 10 percent implementation. Trustee membership, long-range plans, the motivational case, experienced staff, adequate budgets, prospect research, supportive communication all meld into a plan…

  10. Irradiation-induced Ag nanocluster nucleation in silicate glasses: Analogy with photography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Espiau de Lamaestre, R.; Fontainebleau Research Center, Corning SA, 77210 Avon; Bea, H.

    2007-11-15

    The synthesis of Ag nanoclusters in soda lime silicate glasses and silica was studied by optical absorption and electron spin resonance experiments under both low (gamma ray) and high (MeV ion) deposited energy density irradiation conditions. Both types of irradiation create electrons and holes whose density and thermal evolution--notably via their interaction with defects--are shown to determine the clustering and growth rates of Ag nanocrystals. We thus establish the influence of redox interactions of defects and silver (poly)ions. The mechanisms are similar to the latent image formation in photography: Irradiation-induced photoelectrons are trapped within the glass matrix, notably on dissolvedmore » noble metal ions and defects, which are thus neutralized (reverse oxidation reactions are also shown to exist). Annealing promotes metal atom diffusion, which, in turn, leads to cluster nuclei formation. The cluster density depends not only on the irradiation fluence but also--and primarily--on the density of deposited energy and the redox properties of the glass. Ion irradiation (i.e., large deposited energy density) is far more effective in cluster formation, despite its lower neutralization efficiency (from Ag{sup +} to Ag{sup 0}) as compared to gamma photon irradiation.« less

  11. Hydrogen-Rich Water Ameliorates Total Body Irradiation-Induced Hematopoietic Stem Cell Injury by Reducing Hydroxyl Radical

    PubMed Central

    Xue, Xiaolei; Han, Xiaodan; Li, Yuan; Lu, Lu; Li, Deguan

    2017-01-01

    We examined whether consumption of hydrogen-rich water (HW) could ameliorate hematopoietic stem cell (HSC) injury in mice with total body irradiation (TBI). The results indicated that HW alleviated TBI-induced HSC injury with respect to cell number alteration and to the self-renewal and differentiation of HSCs. HW specifically decreased hydroxyl radical (∙OH) levels in the c-kit+ cells of 4 Gy irradiated mice. Proliferative bone marrow cells (BMCs) increased and apoptotic c-kit+ cells decreased in irradiated mice uptaken with HW. In addition, the mean fluorescence intensity (MFI) of γ-H2AX and percentage of 8-oxoguanine positive cells significantly decreased in HW-treated c-kit+ cells, indicating that HW can alleviate TBI-induced DNA damage and oxidative DNA damage in c-kit+ cells. Finally, the cell cycle (P21), cell apoptosis (BCL-XL and BAK), and oxidative stress (NRF2, HO-1, NQO1, SOD, and GPX1) proteins were significantly altered by HW in irradiated mouse c-kit+ cells. Collectively, the present results suggest that HW protects against TBI-induced HSC injury. PMID:28243358

  12. Hydrogen-Rich Water Ameliorates Total Body Irradiation-Induced Hematopoietic Stem Cell Injury by Reducing Hydroxyl Radical.

    PubMed

    Zhang, Junling; Xue, Xiaolei; Han, Xiaodan; Li, Yuan; Lu, Lu; Li, Deguan; Fan, Saijun

    2017-01-01

    We examined whether consumption of hydrogen-rich water (HW) could ameliorate hematopoietic stem cell (HSC) injury in mice with total body irradiation (TBI). The results indicated that HW alleviated TBI-induced HSC injury with respect to cell number alteration and to the self-renewal and differentiation of HSCs. HW specifically decreased hydroxyl radical ( ∙ OH) levels in the c-kit + cells of 4 Gy irradiated mice. Proliferative bone marrow cells (BMCs) increased and apoptotic c-kit + cells decreased in irradiated mice uptaken with HW. In addition, the mean fluorescence intensity (MFI) of γ -H2AX and percentage of 8-oxoguanine positive cells significantly decreased in HW-treated c-kit + cells, indicating that HW can alleviate TBI-induced DNA damage and oxidative DNA damage in c-kit + cells. Finally, the cell cycle (P21), cell apoptosis (BCL-XL and BAK), and oxidative stress (NRF2, HO-1, NQO1, SOD, and GPX1) proteins were significantly altered by HW in irradiated mouse c-kit + cells. Collectively, the present results suggest that HW protects against TBI-induced HSC injury.

  13. Drug-Induced Hematologic Syndromes

    PubMed Central

    Mintzer, David M.; Billet, Shira N.; Chmielewski, Lauren

    2009-01-01

    Objective. Drugs can induce almost the entire spectrum of hematologic disorders, affecting white cells, red cells, platelets, and the coagulation system. This paper aims to emphasize the broad range of drug-induced hematological syndromes and to highlight some of the newer drugs and syndromes. Methods. Medline literature on drug-induced hematologic syndromes was reviewed. Most reports and reviews focus on individual drugs or cytopenias. Results. Drug-induced syndromes include hemolytic anemias, methemoglobinemia, red cell aplasia, sideroblastic anemia, megaloblastic anemia, polycythemia, aplastic anemia, leukocytosis, neutropenia, eosinophilia, immune thrombocytopenia, microangiopathic syndromes, hypercoagulability, hypoprothrombinemia, circulating anticoagulants, myelodysplasia, and acute leukemia. Some of the classic drugs known to cause hematologic abnormalities have been replaced by newer drugs, including biologics, accompanied by their own syndromes and unintended side effects. Conclusions. Drugs can induce toxicities spanning many hematologic syndromes, mediated by a variety of mechanisms. Physicians need to be alert to the potential for iatrogenic drug-induced hematologic complications. PMID:19960059

  14. Protective effects of sodium selenite supplementation against irradiation-induced damage in non-cancerous human esophageal cells.

    PubMed

    Puspitasari, Irma M; Yamazaki, Chiho; Abdulah, Rizky; Putri, Mirasari; Kameo, Satomi; Nakano, Takashi; Koyama, Hiroshi

    2017-01-01

    The administration of radioprotective compounds is one approach to preventing radiation damage in non-cancerous tissues. Therefore, radioprotective compounds are crucial in clinical radiotherapy. Selenium is a radioprotective compound that has been used in previous clinical studies of radiotherapy. However, evidence regarding the effectiveness of selenium in radiotherapy and the mechanisms underlying the selenium-induced reduction of the side effects of radiotherapy remains insufficient. To further investigate the effectiveness of selenium in radiotherapy, the present study examined the protective effects of sodium selenite supplementation administered prior to X-ray radiation treatment in CHEK-1 non-cancerous human esophageal cells. Sodium selenite supplementation increased glutathione peroxidase 1 (GPx-1) activity in a dose- and time-dependent manner. The sodium selenite dose that induced the highest GPx-1 activity was determined to be 50 nM for 72 h prior to radiotherapy. The half-maximal inhibitory concentration of sodium selenite in CHEK-1 cells was 3.6 µM. Sodium selenite supplementation increased the survival rate of the cells in a dose-dependent manner and enhanced the degree of cell viability at 72 h post-irradiation (P<0.05). Combined treatment with 50 nM sodium selenite and 2 gray (Gy) X-ray irradiation decreased the number of sub-G 1 cells from 5.9 to 4.2% (P<0.05) and increased the proportion of G 1 cells from 58.8 to 62.1%, compared with 2 Gy X-ray irradiation alone; however, this difference was not statistically significant (P=1.00). Western blot analysis revealed that treatment with 2 Gy X-ray irradiation significantly increased the expression levels of cleaved poly (ADP-ribose) polymerase (PARP; P<0.05). In addition, combined treatment with 50 nM sodium selenite and 2 Gy X-ray irradiation reduced the expression levels of cleaved PARP protein, compared with 2 Gy X-ray irradiation alone; however, this reduction was not statistically significant (P=0

  15. Low-energy electron irradiation induced top-surface nanocrystallization of amorphous carbon film

    NASA Astrophysics Data System (ADS)

    Chen, Cheng; Fan, Xue; Diao, Dongfeng

    2016-10-01

    We report a low-energy electron irradiation method to nanocrystallize the top-surface of amorphous carbon film in electron cyclotron resonance plasma system. The nanostructure evolution of the carbon film as a function of electron irradiation density and time was examined by transmission electron microscope (TEM) and Raman spectroscopy. The results showed that the electron irradiation gave rise to the formation of sp2 nanocrystallites in the film top-surface within 4 nm thickness. The formation of sp2 nanocrystallite was ascribed to the inelastic electron scattering in the top-surface of carbon film. The frictional property of low-energy electron irradiated film was measured by a pin-on-disk tribometer. The sp2 nanocrystallized top-surface induced a lower friction coefficient than that of the original pure amorphous film. This method enables a convenient nanocrystallization of amorphous surface.

  16. The developmental toxicity and apoptosis in zebrafish eyes induced by carbon-ion irradiation.

    PubMed

    Zhou, Rong; Zhang, Hong; Wang, Zhenguo; Zhou, Xin; Si, Jing; Gan, Lu; Li, Jianzhen; Liu, Yang

    2015-10-15

    Heavy ions have become potentially radiotherapeutic tools. However, studies of the effects on development of normal organs were limited. Using a zebrafish model, this study investigated the potential developmental toxicity and cell apoptosis rates in eyes exposed to carbon-ion irradiation. Zebrafish embryos at 12h post-fertilization (hpf) were irradiated using (12)C(6+) ion beams at doses of 2, 4, and 8 Gy. The reactive oxygen species (ROS) concentration was detected using the dichlorofluorescein-diacetate at 24, 48, and 72 hpf. Apoptosis was assessed by acridine orange staining at 24, 48, and 72 hpf and was also detected using the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling assay, at 72 hpf. The expression of genes governing apoptosis was examined using real-time polymerase chain reaction at 24 hpf. Eye size was measured at 144 hpf. Ion irradiation with (12)C(6+) induced a significant increase in cell apoptosis at 24, 48 and 72 hpf. However, there was no significant increase in the ROS concentration at 24, 48, and 72 hpf. The proapoptotic genes, including P53, Bax, and Puma, were significantly upregulated. Two antiapoptotic genes, Mdm2 and Bcl-2, were significantly downregulated, and the expression levels of Capspase-9 and Caspase-3 were significantly increased. Microphthalmia was noted in the 8 Gy irradiated group. These results suggested that carbon-ion irradiation induced apoptosis through the p53 pathway in zebrafish eyes independent of ROS generation. Irradiation at high doses may disrupt eye development of zebrafish embryos. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Modeling thermal and irradiation-induced swelling effects on the integrity of Ti3SiC2/SiC joints

    NASA Astrophysics Data System (ADS)

    Nguyen, Ba Nghiep; Henager, Charles H.; Kurtz, Richard J.

    2017-11-01

    Previously, results for CVD-SiC joined by a solid state displacement reaction to form a dual-phase SiC/MAX phase joint subsequently irradiated at 800 °C to 5 dpa indicated some cracking in the joint. This paper elucidates the cracking origin by developing a model that accounts for differential thermal expansion and irradiation-induced swelling between the substrate and joint materials by using a continuum damage mechanics approach with support from micromechanical modeling. Damage accumulation in joined specimens irradiated at four temperatures (300 °C, 400 °C, 500 °C and 800 °C) is analyzed. We assume the experimental irradiation dose is sufficient to cause saturation swelling in SiC. The analyses indicate that the SiC/MAX joint survives irradiation-induced swelling at all the irradiation temperatures considered. The joint experiences only minor damage when heated to and irradiated at 800 °C as well as cooling to room temperature. The prediction agrees with the experimental findings available for this case. However, the joint heated to 300 °C suffers severe damage during irradiation-induced swelling at this temperature, and additional damage after cooling to room temperature. Irradiation at 400 °C and subsequent cooling to room temperature produced similar damage to the irradiation 300 °C case, but to a lesser extent. The joint heated to 500 °C and irradiated at this temperature suffered only very minor damage, but further moderate damage occurred after cooling to room temperature.

  18. Successful Thrombolysis and Spasmolysis of Acute Leg Ischemia after Accidental Intra-arterial Injection of Dissolved Flunitrazepam Tablets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Radeleff, B., E-mail: Boris_radeleff@med.uni-heidelberg.de; Stampfl, U.; Sommer, C.-M.

    2011-10-15

    A 37-year-old man with known intravenous drug abuse presented in the surgical ambulatory care unit with acute leg ischemia after accidental intra-arterial injection of dissolved flunitrazepam tablets into the right femoral artery. A combination of anticoagulation, vasodilatation, and local selective and superselective thrombolysis with urokinase was performed to salvage the leg. As a result of the severe ischemia-induced pain, the patient had to be monitored over the complete therapy period on the intensive care unit with permanent administration of intravenous fluid and analgetics. We describe the presenting symptoms and the interventional technique, and we discuss the recent literature regarding themore » management of accidental intra-arterial injection of dissolved flunitrazepam tablets.« less

  19. Degos disease: a new simulator of non-accidental injury.

    PubMed

    Moss, Celia; Wassmer, Evangeline; Debelle, Geoff; Hackett, Scott; Goodyear, Helen; Malcomson, Roger; Ryder, Clive; Sgouros, Spyros; Shahidullah, Hossain

    2009-08-01

    Recent high-profile cases have made paediatricians very aware of the serious implications of either missing or wrongly diagnosing non-accidental injury. Subdural fluid collections in non-mobile infants usually represent haemorrhage caused by non-accidental injury. We report a 6-month-old male who presented to the Accident and Emergency Department of Birmingham Heartlands Hospital with bilateral subdural fluid collections and skin ulcers resembling cigarette burns. Non-accidental injury was considered to be the most likely diagnosis. However, while under observation in hospital, the child's neurological condition deteriorated with progressive cerebral infarctions, and serial photographs of the skin lesions showed failure to heal. The revised diagnosis, confirmed histologically, was Degos disease, an extremely rare and often fatal occlusive vasculopathy. The child was treated palliatively and died 8 weeks after presentation. This report informs doctors of a new simulator of non-accidental injury to be considered in infants with otherwise unexplained subdural fluid collections.

  20. On the modeling of irradiation-induced homogeneous precipitation in proton-bombarded Ni-Si solid solutions

    NASA Astrophysics Data System (ADS)

    Lam, Nghi Q.; Janghorban, K.; Ardell, A. J.

    1981-10-01

    Irradiation-induced solute redistribution leading to precipitation of coherent γ' particles in undersaturated Ni-based solid solutions containing 6 and 8 at.% Si during 400-keV proton bombardment was modeled, based on the concept of solute segregation in concentrated alloys under spatially-dependent defect production conditions. The combined effects of (i) an extremely large difference between the defect production rates in the peak-damage and mid-range regions during irradiation and (ii) a preferential coupling between the interstitial and solute fluxes generate a net transient flux of Si atoms into the mid-range region, which is much larger than the solute flux out of this location. As a result, the Si concentration exceeds the solubility limit and homogeneous precipitation of the γ' phase occurs in this particular region of the irradiated samples. The spatial, compositional and temperature dependences of irradiation-induced homogeneous precipitation derived from the present theoretical calculations are in good qualitative agreement with experimental observations

  1. Cytoplasmic Irradiation Induces Metabolic Shift in Human Small Airway Epithelial Cells via Activation of Pim-1 Kinase.

    PubMed

    Wu, Jinhua; Zhang, Qin; Wuu, Yen-Ruh; Zou, Sirui; Hei, Tom K

    2017-04-01

    The unique cellular and molecular consequences of cytoplasmic damage caused by ionizing radiation were studied using a precision microbeam irradiator. Our results indicated that targeted cytoplasmic irradiation induced metabolic shift from an oxidative to glycolytic phenotype in human small airway epithelial cells (SAE). At 24 h postirradiation, there was an increase in the mRNA expression level of key glycolytic enzymes as well as lactate secretion in SAE cells. Using RNA-sequencing analysis to compare genes that were responsive to cytoplasmic versus nuclear irradiation, we found a glycolysis related gene, Pim-1, was significantly upregulated only in cytoplasmic irradiated SAE cells. Inhibition of Pim-1 activity using the selective pharmaceutic inhibitor Smi-4a significantly reduced the level of lactate production and glucose uptake after cytoplasmic irradiation. In addition, Pim-1 also inhibited AMPK activity, which is a well-characterized negative regulator of glycolysis. Distinct from the glycolysis induced by cytoplasmic irradiation, targeted nuclear irradiation also induced a transient and minimal increase in glycolysis that correlated with increased expression of Hif-1α. In an effort to explore the underline mechanism, we found that inhibition of mitochondria fission using the cell-permeable inhibitor mdivi-1 suppressed the induction of Pim-1, thus confirming Pim-1 upregulation as a downstream effect of mitochondrial dysfunction. Our data show and, for the first time, that cytoplasmic irradiation mediate expression level of Pim-1, which lead to glycolytic shift in SAE cells. Additionally, since glycolysis is frequently linked to cancer cell metabolism, our findings further suggest a role of cytoplasmic damage in promoting neoplastic changes.

  2. Cytoplasmic Irradiation Induces Metabolic Shift in Human Small Airway Epithelial Cells via Activation of Pim-1 Kinase

    PubMed Central

    Wu, Jinhua; Zhang, Qin; Wuu, Yen-Ruh; Zou, Sirui; Hei, Tom K.

    2017-01-01

    The unique cellular and molecular consequences of cytoplasmic damage caused by ionizing radiation were studied using a precision microbeam irradiator. Our results indicated that targeted cytoplasmic irradiation induced metabolic shift from an oxidative to glycolytic phenotype in human small airway epithelial cells (SAE). At 24 h postirradiation, there was an increase in the mRNA expression level of key glycolytic enzymes as well as lactate secretion in SAE cells. Using RNA-sequencing analysis to compare genes that were responsive to cytoplasmic versus nuclear irradiation, we found a glycolysis related gene, Pim-1, was significantly upregulated only in cytoplasmic irradiated SAE cells. Inhibition of Pim-1 activity using the selective pharmaceutic inhibitor Smi-4a significantly reduced the level of lactate production and glucose uptake after cytoplasmic irradiation. In addition, Pim-1 also inhibited AMPK activity, which is a well-characterized negative regulator of glycolysis. Distinct from the glycolysis induced by cytoplasmic irradiation, targeted nuclear irradiation also induced a transient and minimal increase in glycolysis that correlated with increased expression of Hif-1α. In an effort to explore the underline mechanism, we found that inhibition of mitochondria fission using the cell-permeable inhibitor mdivi-1 suppressed the induction of Pim-1, thus confirming Pim-1 upregulation as a downstream effect of mitochondrial dysfunction. Our data show and, for the first time, that cytoplasmic irradiation mediate expression level of Pim-1, which lead to glycolytic shift in SAE cells. Additionally, since glycolysis is frequently linked to cancer cell metabolism, our findings further suggest a role of cytoplasmic damage in promoting neoplastic changes. PMID:28170315

  3. Blue light irradiation-induced oxidative stress in vivo via ROS generation in rat gingival tissue.

    PubMed

    Yoshida, Ayaka; Shiotsu-Ogura, Yukako; Wada-Takahashi, Satoko; Takahashi, Shun-suke; Toyama, Toshizo; Yoshino, Fumihiko

    2015-10-01

    It has been reported that oxidative stress with reactive oxygen species (ROS) generation is induced by blue light irradiation to a living body. Only limited research has been reported in dental field on the dangers of blue light, mostly focusing on cytotoxicity associated with heat injury of dental pulp. We thus performed an in vivo study on oral tissue exposed to blue light. ROS generated upon blue light irradiation of flavin adenine dinucleotide were measured by electron spin resonance spectroscopy. After blue light irradiation, the palatal gingiva of Wistar rats were isolated. Collected samples were subjected to biochemical analysis of lipid peroxidation and glutathione. Singlet oxygen was generated by blue light irradiation, but was significantly quenched in an N-acetyl-L-cysteine (NAC) concentration-dependent manner. Blue light significantly accelerated oxidative stress and increased the oxidized glutathione levels in gingival tissue. These effects were also inhibited by NAC pre-administration. The results suggest that blue light irradiation at clinical levels of tooth bleaching treatment may enhance lipid peroxidation by the induction of oxidative stress and the consumption of a significant amount of intracellular glutathione. In addition, NAC might be an effective supplement for the protection of oral tissues against blue light irradiation-induced oxidative damage. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Effects of Fe concentration on the ion-irradiation induced defect evolution and hardening in Ni-Fe solid solution alloys

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jin, Ke; Guo, Wei; Lu, Chenyang

    Understanding alloying effects on the irradiation response of structural materials is pivotal in nuclear engineering. In order to systematically explore the effects of Fe concentration on the irradiation-induced defect evolution and hardening in face-centered cubic Ni-Fe binary solid solution alloys, single crystalline Ni-xFe (x = 0–60 at%) alloys have been grown and irradiated with 1.5 MeV Ni ions. The irradiations have been performed over a wide range of fluences from 3 × 10 13 to 3 × 10 16 cm -2 at room temperature. Ion channeling technique has shown reduced damage accumulation with increasing Fe concentration in the low fluencemore » regime, which is consistent to the results from molecular dynamic simulations. We did not observe any irradiation-induced compositional segregation in atom probe tomography within the detection limit, even in the samples irradiated with high fluence Ni ions. Transmission electron microscopy analyses have further demonstrated that the defect size significantly decreases with increasing Fe concentration, indicating a delay in defect evolution. Furthermore, irradiation induced hardening has been measured by nanoindentation tests. Ni and the Ni-Fe alloys have largely different initial hardness, but they all follow a similar trend for the increase of hardness as a function of irradiation fluence.« less

  5. Effects of Fe concentration on the ion-irradiation induced defect evolution and hardening in Ni-Fe solid solution alloys

    DOE PAGES

    Jin, Ke; Guo, Wei; Lu, Chenyang; ...

    2016-12-01

    Understanding alloying effects on the irradiation response of structural materials is pivotal in nuclear engineering. In order to systematically explore the effects of Fe concentration on the irradiation-induced defect evolution and hardening in face-centered cubic Ni-Fe binary solid solution alloys, single crystalline Ni-xFe (x = 0–60 at%) alloys have been grown and irradiated with 1.5 MeV Ni ions. The irradiations have been performed over a wide range of fluences from 3 × 10 13 to 3 × 10 16 cm -2 at room temperature. Ion channeling technique has shown reduced damage accumulation with increasing Fe concentration in the low fluencemore » regime, which is consistent to the results from molecular dynamic simulations. We did not observe any irradiation-induced compositional segregation in atom probe tomography within the detection limit, even in the samples irradiated with high fluence Ni ions. Transmission electron microscopy analyses have further demonstrated that the defect size significantly decreases with increasing Fe concentration, indicating a delay in defect evolution. Furthermore, irradiation induced hardening has been measured by nanoindentation tests. Ni and the Ni-Fe alloys have largely different initial hardness, but they all follow a similar trend for the increase of hardness as a function of irradiation fluence.« less

  6. Suppressing effect of low-dose gamma-ray irradiation on collagen-induced arthritis.

    PubMed

    Nakatsukasa, Hiroko; Tsukimoto, Mitsutoshi; Ohshima, Yasuhiro; Tago, Fumitoshi; Masada, Ayako; Kojima, Shuji

    2008-07-01

    We previously reported attenuation of autoimmune disease by low-dose gamma-ray irradiation in MRL-lpr/lpr mice. Here, we studied the effect of low-dose gamma-ray irradiation on collagen-induced arthritis (CIA) in DBA/1J mice. Mice were immunized with type II collagen, and exposed to low-dose gamma-rays (0.5 Gy per week for 5 weeks). Paw swelling, redness, and bone degradation were suppressed by irradiation, which also delayed the onset of pathological change and reduced the severity of the arthritis. Production of tumor necrosis factor-alpha, interferon-gamma, and interleukin-6, which play important roles in the onset of CIA, was suppressed by the irradiation. The level of anti-type II collagen antibody, which is essential for the onset of CIA, was also lower in irradiated CIA mice. The population of plasma cells was increased in CIA mice, but irradiation blocked this increase. Since regulatory T cells are known to be involved in suppression of autoimmune disease, the population of CD4(+)CD25(+)Foxp3(+) regulatory T cells was measured. Intriguingly, a significant increase of these regulatory T cells was found in irradiated CIA mice. Overall, our data suggest that low-dose gamma-ray irradiation could attenuate CIA through suppression of pro-inflammatory cytokines and autoantibody production, and induction of regulatory T cells.

  7. Particle irradiation induces FGF2 expression in normal human lens cells

    NASA Technical Reports Server (NTRS)

    Chang, P. Y.; Bjornstad K, A.; Chang, E.; McNamara, M.; Barcellos-Hoff, M. H.; Lin, S. P.; Aragon, G.; Polansky, J. R.; Lui, G. M.; Blakely, E. A.

    2000-01-01

    Particle Irradiation Induces FGF2 Expression in Normal Human Lens Cells. Particle radiations, including both proton and helium-ion beams, have been used to successfully treat choroidal melanoma, but with the complication of radiation-induced cataract. We have investigated a role for radiation-induced changes in the expression of basic fibroblast growth factor (FGF2) gene expression as part of the mechanism(s) underlying lens cell injury associated with cataract. Normal human lens epithelial (HLE) cells were cultured in vitro on extracellular matrix (ECM) originated from bovine corneal endothelial cells. This study reports evidence for rapid but transient induction of FGF2 transcripts, an increase of between 5- and 8-fold, within 0.5 h after exposure to particle radiation, followed by another wave of increased transcription at 2-3 h postirradiation. Immunofluorescence results confirm the enhanced levels of FGF2 protein rapidly after exposure to protons or helium ions, followed by another wave of increased activity unique to helium at 6 h postirradiation. This second wave of increased immunoreactivity was not observed in the proton-irradiated samples. Total FGF2 protein analysis after helium-ion exposures shows induced expression of three FGF2 isoforms, with an increase of up to 2-fold in the 18-kDa low-molecular-weight species. Studies of the effects of protons on individual FGF2 protein isoforms are in progress. Several mechanisms involving a role for FGF2 in radiation-induced cataract are discussed.

  8. Decrease in hematopoietic stem cell domains as a delayed effect of x-irradiation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maloney, M.A.; Lamela, R.A.; Patt, H.M.

    Although the hematopoietic integrity of locally X-irradiated sites can be restored for a time even after fairly large doses, a secondary aplasia often occurs some months later. To gain further insight into this delayed effect within the framework of the stem cell regulatory domain hypothesis, we characterized the growth kinetics of spleen colony forming units (CFU-S) in WBB6FI-+/+ bone marrow transplanted into WBB6FI-W/WV mice in which one leg had been exposed to 10-30 Gy of X rays 4-5 months previously. Compared to unirradiated contralateral marrow, fewer CFU-S either reached the previously irradiated marrow or were seeded into sites that couldmore » support growth. The initial exponential growth of effectively seeded CFU-S was unchanged, but growth deceleration (inflection point) occurred at a lower level of CFU-S in marrow previously irradiated with 20-30 Gy. This change in the inflection point indicates a radiation dose-dependent decrease consistent with the decrease in bone marrow cellularity. The decrease in effective stem cell domains after 20 Gy was calculated to be about 35%. We interpret these results to reflect the highly localized nature of delayed radiation damage to the marrow microenvironment.« less

  9. The fine structure of electron irradiation induced EL2-like defects in n-GaAs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tunhuma, S. M.; Auret, F. D.; Legodi, M. J.

    2016-04-14

    Defects induced by electron irradiation in n-GaAs have been studied using deep level transient spectroscopy (DLTS) and Laplace DLTS (L-DLTS). The E{sub 0.83} (EL2) is the only defect observed prior to irradiation. Ru/n-GaAs Schottky diodes were irradiated with high energy electrons from a Sr-90 radionuclide up to a fluence of 2.45 × 10{sup 13} cm{sup −2}. The prominent electron irradiation induced defects, E{sub 0.04}, E{sub 0.14}, E{sub 0.38}, and E{sub 0.63}, were observed together with the metastable E{sub 0.17}. Using L-DLTS, we observed the fine structure of a broad base EL2-like defect peak. This was found to be made up of the E{submore » 0.75}, E{sub 0.83}, and E{sub 0.85} defects. Our study reveals that high energy electron irradiation increases the concentration of the E{sub 0.83} defect and introduces a family of defects with electronic properties similar to those of the EL2.« less

  10. Single Low-Dose Ionizing Radiation Induces Genotoxicity in Adult Zebrafish and its Non-Irradiated Progeny.

    PubMed

    Lemos, J; Neuparth, T; Trigo, M; Costa, P; Vieira, D; Cunha, L; Ponte, F; Costa, P S; Metello, L F; Carvalho, A P

    2017-02-01

    This study investigated to what extent a single exposure to low doses of ionizing radiation can induce genotoxic damage in irradiated adult zebrafish (Danio rerio) and its non-irradiated F1 progeny. Four groups of adult zebrafish were irradiated with a single dose of X-rays at 0 (control), 100, 500 and 1000 mGy, respectively, and couples of each group were allowed to reproduce following irradiation. Blood of parental fish and whole-body offspring were analysed by the comet assay for detection of DNA damage. The level of DNA damage in irradiated parental fish increased in a radiation dose-dependent manner at day 1 post-irradiation, but returned to the control level thereafter. The level of DNA damage in the progeny was directly correlated with the parental irradiation dose. Results highlight the genotoxic risk of a single exposure to low-dose ionizing radiation in irradiated individuals and also in its non-irradiated progeny.

  11. Modeling thermal and irradiation-induced swelling effects on the integrity of Ti 3SiC 2/SiC joints

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nguyen, Ba Nghiep; Henager, Charles H.; Kurtz, Richard J.

    Previously, results for CVD-SiC joined by a solid state displacement reaction to form a dual-phase SiC/MAX phase joint subsequently irradiated at 800 °C to 5 dpa indicated some cracking in the joint. Here, this paper elucidates the cracking origin by developing a model that accounts for differential thermal expansion and irradiation-induced swelling between the substrate and joint materials by using a continuum damage mechanics approach with support from micromechanical modeling. Damage accumulation in joined specimens irradiated at four temperatures (300 °C, 400 °C, 500 °C and 800 °C) is analyzed. We assume the experimental irradiation dose is sufficient to causemore » saturation swelling in SiC. The analyses indicate that the SiC/MAX joint survives irradiation-induced swelling at all the irradiation temperatures considered. The joint experiences only minor damage when heated to and irradiated at 800 °C as well as cooling to room temperature. The prediction agrees with the experimental findings available for this case. However, the joint heated to 300 °C suffers severe damage during irradiation-induced swelling at this temperature, and additional damage after cooling to room temperature. Irradiation at 400 °C and subsequent cooling to room temperature produced similar damage to the irradiation 300 °C case, but to a lesser extent. Finally, the joint heated to 500 °C and irradiated at this temperature suffered only very minor damage, but further moderate damage occurred after cooling to room temperature.« less

  12. Modeling thermal and irradiation-induced swelling effects on the integrity of Ti 3SiC 2/SiC joints

    DOE PAGES

    Nguyen, Ba Nghiep; Henager, Charles H.; Kurtz, Richard J.

    2017-09-08

    Previously, results for CVD-SiC joined by a solid state displacement reaction to form a dual-phase SiC/MAX phase joint subsequently irradiated at 800 °C to 5 dpa indicated some cracking in the joint. Here, this paper elucidates the cracking origin by developing a model that accounts for differential thermal expansion and irradiation-induced swelling between the substrate and joint materials by using a continuum damage mechanics approach with support from micromechanical modeling. Damage accumulation in joined specimens irradiated at four temperatures (300 °C, 400 °C, 500 °C and 800 °C) is analyzed. We assume the experimental irradiation dose is sufficient to causemore » saturation swelling in SiC. The analyses indicate that the SiC/MAX joint survives irradiation-induced swelling at all the irradiation temperatures considered. The joint experiences only minor damage when heated to and irradiated at 800 °C as well as cooling to room temperature. The prediction agrees with the experimental findings available for this case. However, the joint heated to 300 °C suffers severe damage during irradiation-induced swelling at this temperature, and additional damage after cooling to room temperature. Irradiation at 400 °C and subsequent cooling to room temperature produced similar damage to the irradiation 300 °C case, but to a lesser extent. Finally, the joint heated to 500 °C and irradiated at this temperature suffered only very minor damage, but further moderate damage occurred after cooling to room temperature.« less

  13. The Role of DNA Methylation Changes in Radiation-Induced Bystander Effects in cranial irradiated Mice

    NASA Astrophysics Data System (ADS)

    Zhang, Meng; Sun, Yeqing; Xue, Bei; Wang, Xinwen; Wang, Jiawen

    2016-07-01

    Heavy-ion radiation could lead to bystander effect in neighboring non-hit cells by signals released from directly-irradiated cells. The exact mechanisms of radiation-induced bystander effect in distant organ remain obscure, yet accumulating evidence points to the role of DNA methylation changes in bystander effect. To identify the molecular mechanism that underlies bystander effects of heavy-ion radiation, the male Balb/c and C57BL mice were cranial exposed to 40, 200, 2000mGy dose of carbon heavy-ion radiation, while the rest of the animal body was shielded. The γH2AX foci as the DNA damage biomarker in directly irradiation organ ear and the distant organ liver were detected on 0, 1, 2, 6, 12 and 24h after radiation, respectively. Methylation-sensitive amplifcation polymorphism (MSAP) was used to monitor the level of polymorphic genomic DNA methylation changed with dose and time effects. The results show that cranial irradiated mice could induce the γH2AX foci and genomic DNA methylation changes significantly in both the directly irradiation organ ear and the distant organ liver. The percent of DNA methylation changes were time-dependent and tissue-specific. Demethylation polymorphism rate were highest separately at 1 h in 200 mGy and 6 h in 2000 mGy after irradiation in ear. The global DNA methylation changes tended to occur in the CG sites. We also found that the numbers of γH2AX foci and the genomic methylation changes of heavy-ion radiation-induced bystander effect in liver could be obvious 1 h after radiation and achieved the maximum at 6 h, while the changes could recover gradually at 12 h. The results suggest that mice head exposed to heavy-ion radiation can induce damage and methylation pattern changed in both directly radiation organ ear and distant organ liver. Moreover, our findings are important to understand the molecular mechanism of radiation induced bystander effects in vivo. Keywords: Heavy-ion radiation; Bystander effect; DNA methylation; γH2

  14. Irradiation-induced grain growth and defect evolution in nanocrystalline zirconia with doped grain boundaries

    DOE PAGES

    Dey, Sanchita; Mardinly, John; Wang, Yongqiang; ...

    2016-05-27

    Grain boundaries are effective sinks for radiation-induced defects, ultimately impacting the radiation tolerance of nanocrystalline materials (dense materials with nanosized grains) against net defect accumulation. However, irradiation-induced grain growth leads to grain boundary area decrease, shortening potential benefits of nanostructures. A possible approach to mitigate this is the introduction of dopants to target a decrease in grain boundary mobility or a reduction in grain boundary energy to eliminate driving forces for grain growth (using similar strategies as to control thermal growth). Here, in this study, we tested this concept in nanocrystalline zirconia doped with lanthanum. Although the dopant is observedmore » to segregate to the grain boundaries, causing grain boundary energy decrease and promoting dragging forces for thermally activated boundary movement, irradiation induced grain growth could not be avoided under heavy ion irradiation, suggesting a different growth mechanism as compared to thermal growth. Furthermore, it is apparent that reducing the grain boundary energy reduced the effectiveness of the grain boundary as sinks, and the number of defects in the doped material is higher than in undoped (La-free) YSZ.« less

  15. Fatal hemorrhagic cystitis induced by pelvic irradiation and cyclophosphamide therapy. Case reports and review

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Price, W.E.; Keldahl, L.R.

    The potent cytotoxic drug cyclophosphamide has been used extensively for neoplastic and non-neoplastic diseases. Patients taking this drug may have received or may be receiving pelvic irradiation concurrently. This report describes two patients who developed fatal hemorrhagic cystitis induced by pelvic irradiation and cyclophosphamide therapy. Etiology, incidence, pathologic descriptions, and diagnostic and therapeutic aspects of this entity are described. The incidence and risk of serious, life-threatening bladder hemorrhage from cyclophosphamide therapy is increased by prior or concurrent pelvic irradiation. Alternative cytotoxic, non-urotoxic chemotherapy should be used in these high-risk patients.

  16. Irradiation-induced creep in metallic nanolaminates characterized by In situ TEM pillar nanocompression

    DOE PAGES

    Dillon, Shen J.; Bufford, Daniel C.; Jawaharram, Gowtham S.; ...

    2017-04-13

    Our work reports on irradiation-induced creep (IIC) measured on nanolaminate (Cu-W and Ni-Ag) and nanocrystalline alloys (Cu-W) at room temperature using a combination of heavy ion irradiation and nanopillar compression performed concurrently in situ in a transmission electron microscope. Furthermore, we observed appreciable IIC in multilayers with 50 nm layer thicknesses at high stress, ≈½ the yield strength, but not in multilayers with only 5 nm layer thicknesses.

  17. Hazards of Improper Dispensary: Literature Review and Report of an Accidental Chloroform Injection.

    PubMed

    Verma, Prashant; Tordik, Patricia; Nosrat, Ali

    2018-06-01

    Several clear, transparent solutions are used in endodontics. Inappropriate dispensing methods can lead to accidental injection or accidental irrigation. These accidents can cause permanent tissue damage including damage to the bone, periodontium, nerves, and vasculature. This article reports on the consequences of an accidental chloroform injection. Nonsurgical retreatment of tooth #8 was planned as part of a restorative treatment plan in a 69-year-old woman. The dentist accidentally injected chloroform instead of local anesthesia because chloroform was loaded into the anesthetic syringe. The patient experienced severe pain and swelling and soft tissue necrosis and suffered permanent sensory and motor nerve damage. A review of the literature was performed on accidents caused by improper dispensary, namely accidental injections and accidental irrigations. The data were extracted and summarized. Sodium hypochlorite, chlorhexidine, formalin, formocresol, 1:1000 adrenaline, benzalkonium chloride, and lighter fuel were accidentally injected as an intraoral nerve block or as infiltration injections. Bone and soft tissue necrosis, tooth loss, and sensory nerve damage (anesthesia and paresthesia) were the most common consequences reported. Such disastrous events can be prevented by appropriate labeling and separate dispensing methods for each solution. There is a need for disseminating information on toxicity and biocompatibility of materials/solutions used in endodontics. The authors recommend training dental students and endodontic residents on immediate and long-term therapeutic management of patients when an accidental injection or accidental irrigation occurs. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  18. Mistakes in diagnosing non-accidental injury: 10 years' experience

    PubMed Central

    Wheeler, David M; Hobbs, Christopher J

    1988-01-01

    Fifty children who were referred to the child abuse team in Leeds over the 10 years 1976-86 with suspected non-accidental injury were found to have conditions which mimicked non-accidental injury. These included impetigo (nine children) and blue spots (five children). Five children who presented with multiple bruising had haemostatic disorders. Eight children had disorders of the bone. Five children had been previously abused physically. Four showed evidence of neglect. One had evidence of non-accidental injury as well as the condition mimicking abuse. It is emphasised that when child abuse is suspected a sensitive and thorough assessment should be carried out by a paediatrician who is experienced in this. ImagesFIG 1 PMID:3133026

  19. Effects of heavy particle irradiation and diet on amphetamine- and lithium chloride-induced taste avoidance learning in rats

    NASA Technical Reports Server (NTRS)

    Rabin, Bernard M.; Shukitt-Hale, Barbara; Szprengiel, Aleksandra; Joseph, James A.

    2002-01-01

    Rats were maintained on diets containing either 2% blueberry or strawberry extract or a control diet for 8 weeks prior to being exposed to 1.5 Gy of 56Fe particles in the Alternating Gradient Synchrotron at Brookhaven National Laboratory. Three days following irradiation, the rats were tested for the effects of irradiation on the acquisition of an amphetamine- or lithium chloride-induced (LiCl) conditioned taste avoidance (CTA). The rats maintained on the control diet failed to show the acquisition of a CTA following injection of amphetamine. In contrast, the rats maintained on antioxidant diets (strawberry or blueberry extract) continued to show the development of an amphetamine-induced CTA following exposure to 56Fe particles. Neither irradiation nor diet had an effect on the acquisition of a LiCl-induced CTA. The results are interpreted as indicating that oxidative stress following exposure to 56Fe particles may be responsible for the disruption of the dopamine-mediated amphetamine-induced CTA in rats fed control diets; and that a reduction in oxidative stress produced by the antioxidant diets functions to reinstate the dopamine-mediated CTA. The failure of either irradiation or diet to influence LiCl-induced responding suggests that oxidative stress may not be involved in CTA learning following injection of LiCl.

  20. Doctor Ward's Accidental Terrarium.

    ERIC Educational Resources Information Center

    Hershey, David R.

    1996-01-01

    Presents the story of the accidental invention of the Wardian case, or terrarium, by Nathaniel Bagshaw Ward. Advocates the use of this story in teaching precollege biology as an illustration of how a chance event can lead to a major scientific advancement and as an example of the common occurrence of multiple discovery in botany. Contains 34…

  1. Nonuniform Irradiation of the Canine Intestine. 2. Dosimetry

    DTIC Science & Technology

    1990-01-01

    irradiation is accurate assessment In vivo dosimetry was done using Harshaw (Solon, Ohio) TLD - 100 lith- of the injury after either accidental or... vivo TLD dosimetry system allowed measure- 5 and 6. The dose was determined from the median TLD ment of the °Co dose deposited in the canine small...provide replicate measurements. Two separate dosimetry tubes were deveoped (Fig. 1). The first contained 30 TLD cap- doses (1). Nevertheless, current

  2. Electron-beam-irradiation-induced crystallization of amorphous solid phase change materials

    NASA Astrophysics Data System (ADS)

    Zhou, Dong; Wu, Liangcai; Wen, Lin; Ma, Liya; Zhang, Xingyao; Li, Yudong; Guo, Qi; Song, Zhitang

    2018-04-01

    The electron-beam-irradiation-induced crystallization of phase change materials in a nano sized area was studied by in situ transmission electron microscopy and selected area electron diffraction. Amorphous phase change materials changed to a polycrystalline state after being irradiated with a 200 kV electron beam for a long time. The results indicate that the crystallization temperature strongly depends on the difference in the heteronuclear bond enthalpy of the phase change materials. The selected area electron diffraction patterns reveal that Ge2Sb2Te5 is a nucleation-dominated material, when Si2Sb2Te3 and Ti0.5Sb2Te3 are growth-dominated materials.

  3. Dissipative structure in the photo-induced phase under steady light irradiation in the spin crossover complex.

    PubMed

    Nishihara, Taishi; Bousseksou, Azzdine; Tanaka, Koichiro

    2013-12-16

    We report the spatial and temporal dynamics of the photo-induced phase in the iron (II) spin crossover complex Fe(ptz)(6)(BF(4))(2) studied by image measurement under steady light irradiation and transient absorption measurement. The dynamic factors are derived from the spatial and temporal fluctuation of the image in the steady state under light irradiation between 65 and 100 K. The dynamic factors clearly indicate that the fluctuation has a resonant frequency that strongly depends on the temperature, and is proportional to the relaxation rate of the photo-induced phase. This oscillation of the speckle pattern under steady light irradiation is ascribed to the nonlinear interaction between the spin state and the lattice volume at the surface.

  4. Ultraviolet A eye irradiation ameliorates colon carcinoma induced by azoxymethane and dextran sodium sulfate through β-endorphin and methionine-enkephalin.

    PubMed

    Hiramoto, Keiichi; Yokoyama, Satoshi; Yamate, Yurika

    2017-03-01

    We previously reported that ultraviolet (UV) A eye irradiation reduces the ulcerative colitis induced by dextran sodium sulfate (DSS). This study examined the effects of UVA on colon carcinoma induced by azoxymethane (AOM) and DSS. We irradiated the eyes of ICR mice with UVA at a dose of 110 kJ/m 2 using an FL20SBLB-A lamp for the experimental period. In mice treated with these drugs, the symptom of colon carcinoma was reduced by UVA eye irradiation. The levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in the blood were increased in AOM + DSS-treated mice; however, those levels were reduced by UVA eye irradiation. The expression of β-endorphin, methionine-enkephalin (OGF), μ-opioid receptor, and opioid growth factor receptor (OGFR) of the colon was increased in the AOM + DSS-treated mice, and these levels were increased further following UVA eye irradiation. When β-endorphin inhibitor was administered, the ameliorative effect of UVA eye irradiation was reduced, and the effect of eye irradiation disappeared entirely following the administration of naltrexone (inhibitor of both opioid receptor and OGFR). These results suggested that UVA eye irradiation exerts major effects on AOM + DSS-induced colon carcinoma. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Irradiation With Carbon Ion Beams Induces Apoptosis, Autophagy, and Cellular Senescence in a Human Glioma-Derived Cell Line

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jinno-Oue, Atsushi; Shimizu, Nobuaki; 21st Century Center of Excellence Program for Biomedical Research Using Accelerator Technology, Maebashi, Gunma

    2010-01-15

    Purpose: We examined biological responses of human glioma cells to irradiation with carbon ion beams (C-ions). Methods and Materials: A human glioma-derived cell line, NP-2, was irradiated with C-ions. Apoptotic cell nuclei were stained with Hoechst 33342. Induction of autophagy was examined either by staining cells with monodansylcadaverine (MDC) or by Western blotting to detect conversion of microtuble-associated protein light chain 3 (MAP-LC3) (LC3-I) to the membrane-bound form (LC3-II). Cellular senescence markers including induction of senescence-associated beta-galactosidase (SA-beta-gal) were examined. The mean telomere length of irradiated cells was determined by Southern blot hybridization. Expression of tumor suppressor p53 and cyclin/cyclin-dependentmore » kinase inhibitor p21{sup WAF1/CIP1} in the irradiated cells was analyzed by Western blotting. Results: When NP-2 cells were irradiated with C-ions at 6 Gy, the major population of the cells died of apoptosis and autophagy. The residual fraction of attached cells (<1% of initially irradiated cells) could not form a colony: however, they showed a morphological phenotype consistent with cellular senescence, that is, enlarged and flattened appearance. The senescent nature of these attached cells was further indicated by staining for SA-beta-gal. The mean telomere length was not changed after irradiation with C-ions. Phosphorylation of p53 at serine 15 as well as the expression of p21{sup WAF1/CIP1} was induced in NP-2 cells after irradiation. Furthermore, we found that irradiation with C-ions induced cellular senescence in a human glioma cell line lacking functional p53. Conclusions: Irradiation with C-ions induced apoptosis, autophagy, and cellular senescence in human glioma cells.« less

  6. Low-power laser irradiation inhibits amyloid beta-induced cell apoptosis

    NASA Astrophysics Data System (ADS)

    Zhang, Heng; Wu, Shengnan

    2011-03-01

    The deposition and accumulation of amyloid-β-peptide (Aβ) in the brain are considered a pathological hallmark of Alzheimer's disease(AD). Apoptosis is a contributing pathophysiological mechanism of AD. Low-power laser irradiation (LPLI), a non-damage physical therapy, which has been used clinically for decades of years, is shown to promote cell proliferation and prevent apoptosis. Recently, low-power laser irradiation (LPLI) has been applied to moderate AD. In this study, Rat pheochromocytoma (PC12) cells were treated with amyloid beta 25-35 (Aβ25-35) for induction of apoptosis before LPLI treatment. We measured cell viability with CCK-8 according to the manufacture's protocol, the cell viability assays show that low fluence of LPLI (2 J/cm2 ) could inhibit the cells apoptosis. Then using statistical analysis of proportion of apoptotic cells by flow cytometry based on Annexin V-FITC/PI, the assays also reveal that low fluence of LPLI (2 J/cm2 ) could inhibit the Aβ-induced cell apoptosis. Taken together, we demonstrated that low fluence of LPLI (2 J/cm2 ) could inhibit the Aβ-induced cell apoptosis, these results directly point to a therapeutic strategy for the treatment of AD through LPLI.

  7. [The course of pregnancy in congenital thyroid gland aplasia. Case report with special reference to maternal hypothyroidism].

    PubMed

    Bolz, M; Nagel, H

    1994-01-01

    A report is given on a 28 years old women with congenital aplasia of the thyroid gland. She was substituted with thyroxine (300 micrograms per day). Her first pregnancy was complicated by gestational hypertension and pre-eclampsia. Delivery was by forceps. During the first trimester of her second pregnancy, bleedings occurred. The thyroid-stimulating hormone level (TSH-level) was increased (18.3 microU/ml). The patient did not show clinical signs of manifested hypothyroidism. The thyroxine dosis was increased. Bleedings disappeared. Labour was terminated and induced. Labour intra partum was hypoactive. The delivery was again by forceps. The newborn did not show any signals of hypothyroidism. Dysfunction of thyroid gland is associated with reduced fertility. Hypothyroidism in pregnancy is associated with an adverse outcome in fetal health as well as an increase in obstetric complications. Thyroid hormones play a vital role in fetal development and maturation of brain. Women with a hypothyroidism have a lower rate of pregnancy and a higher rate of spontaneous miscarriages compared to a normal population. Recognition and treatment of thyroid disorders in reproductive age occur before conception. Iodoprophylaxis is necessary for prevention of congenital hypothyroidism (cretinism). Iodoprophylaxis is necessary to prevent endemic goiter in pregnancy. Euthyroid goiter is an indication for a combined treatment with jodid and levothyroxine. Treatment should be individualized. Assessment of efficacy of treatment is based on measurement of TSH- and free thyroid hormone (fT4)-levels.

  8. Are pre-hospital deaths from accidental injury preventable?

    PubMed Central

    Hussain, L. M.; Redmond, A. D.

    1994-01-01

    OBJECTIVE--To determine what proportion of pre-hospital deaths from accidental injury--deaths at the scene of the accident and those that occur before the person has reached hospital--are preventable. DESIGN--Retrospective study of all deaths from accidental injury that occurred between 1 January 1987 and 31 December 1990 and were reported to the coroner. SETTING--North Staffordshire. MAIN OUTCOME MEASURES--Injury severity score, probability of survival (probit analysis), and airway obstruction. RESULTS--There were 152 pre-hospital deaths from accidental injury (110 males and 42 females). In the same period there were 257 deaths in hospital from accidental injury (136 males and 121 females). The average age at death was 41.9 years for those who died before reaching hospital, and their average injury severity score was 29.3. In contrast, those who died in hospital were older and equally likely to be males or females. Important neurological injury occurred in 113 pre-hospital deaths, and evidence of airway obstruction in 59. Eighty six pre-hospital deaths were due to road traffic accidents, and 37 of these were occupants in cars. On the basis of the injury severity score and age, death was found to have been inevitable or highly likely in 92 cases. In the remaining 60 cases death had not been inevitable and airway obstruction was present in up to 51 patients with injuries that they might have survived. CONCLUSION--Death was potentially preventable in at least 39% of those who died from accidental injury before they reached hospital. Training in first aid should be available more widely, and particularly to motorists as many pre-hospital deaths that could be prevented are due to road accidents. PMID:8173428

  9. ESR detection of irradiated carob pods (Ceratoniasiliqua L) and its dosimetric feature

    NASA Astrophysics Data System (ADS)

    Tuner, Hasan; Polat, Mustafa

    2017-12-01

    Un-irradiated carob powder exhibited a weak ESR singlet at g = 2.0041 ± 0.0006 with peak-to-peak linewidth (ΔHpp) of 0.33 ± 0.01 mT. Irradiated carob powder exhibited an ESR spectrum consisting many resonance lines and similar to ESR spectrum of sugar in all aspects. A linear function of the absorbed radiation dose was found to describe best the dose-response curves of the ESR signal intensity Ipp. It is concluded that due to the similarity of carob powder ESR spectrum to the irradiated sugar and the fact that it is widely consumed, carob powder has the potential to be used as a retrospective and/or accidental dosimetric material.

  10. Acute renal failure in a pediatric kidney allograft recipient treated with intravenous immunoglobulin for parvovirus B19 induced pure red cell aplasia.

    PubMed

    Subtirelu, Mihail M; Flynn, Joseph T; Schechner, Richard S; Pullman, James M; Feuerstein, Dianne; Del Rio, Marcela

    2005-12-01

    Infection with parvovirus B19 (PV-B19) after solid organ transplantation may cause pure red cell aplasia (PRCA). Intravenous immunoglobulin (IVIg) may be of benefit in clearing the infection. Acute renal failure is a known adverse effect of IVIg administration. A 14-yr-old male received a cadaveric renal transplant. Three weeks after surgery he developed symptomatic anemia (hemoglobin 4.5 g/dL, reticulocyte count 0.2%). Anti-PV-B19 IgM and IgG titers, which had been negative pretransplant, were positive. He received two IVIg infusions as treatment for the PV-B19 infection. Four days after the IVIg infusions he developed non-oliguric acute renal failure (ARF) with a rise in serum creatinine from 1 to 1.8 mg/dL. Allograft biopsy showed changes consistent with an osmotic load. Anemia and the renal failure resolved after transfusions and IVIg. PV-B19 infection in immunosuppressed transplant recipients is associated with significant morbidity and may respond to IVIg therapy. High sucrose IVIg preparations may be associated with renal failure in renal allograft recipients. Adding PV-B19 testing of the donor and recipient to the standard pretransplant evaluation may be beneficial in diagnosing and managing a potential infection. If IVIg is to be used it may be safer to use a sucrose-free IVIg preparation.

  11. A preclinical rodent model of acute radiation-induced lung injury after ablative focal irradiation reflecting clinical stereotactic body radiotherapy.

    PubMed

    Hong, Zhen-Yu; Lee, Hae-June; Choi, Won Hoon; Lee, Yoon-Jin; Eun, Sung Ho; Lee, Jung Il; Park, Kwangwoo; Lee, Ji Min; Cho, Jaeho

    2014-07-01

    In a previous study, we established an image-guided small-animal micro-irradiation system mimicking clinical stereotactic body radiotherapy (SBRT). The goal of this study was to develop a rodent model of acute phase lung injury after ablative irradiation. A radiation dose of 90 Gy was focally delivered to the left lung of C57BL/6 mice using a small animal stereotactic irradiator. At days 1, 3, 5, 7, 9, 11 and 14 after irradiation, the lungs were perfused with formalin for fixation and paraffin sections were stained with hematoxylin and eosin (H&E) and Masson's trichrome. At days 7 and 14 after irradiation, micro-computed tomography (CT) images of the lung were taken and lung functional measurements were performed with a flexiVent™ system. Gross morphological injury was evident 9 days after irradiation of normal lung tissues and dynamic sequential events occurring during the acute phase were validated by histopathological analysis. CT images of the mouse lungs indicated partial obstruction located in the peripheral area of the left lung. Significant alteration in inspiratory capacity and tissue damping were detected on day 14 after irradiation. An animal model of radiation-induced lung injury (RILI) in the acute phase reflecting clinical stereotactic body radiotherapy was established and validated with histopathological and functional analysis. This model enhances our understanding of the dynamic sequential events occurring in the acute phase of radiation-induced lung injury induced by ablative dose focal volume irradiation.

  12. Cross-sectional transmission electron microscopic study of irradiation induced nano-crystallization of nickel in a W/Ni multilayer.

    PubMed

    Bagchi, Sharmistha; Lalla, N P

    2008-06-11

    The present study reports the cross-sectional transmission electron microscopic investigations of swift heavy ion-irradiation induced nano-size recrystallization of Ni in a nearly immiscible W/Ni multilayer structure. Multilayer structures (MLS) of [W(25 Å)/Ni(25 Å)](10BL) were grown on Si-(100) substrate by the ion-beam sputtering technique. The as-synthesized MLS were subjected to 120 MeV-Au(9+) ion-irradiation to a fluence of ∼5 × 10(13) ions cm(-2). Wide-angle x-ray diffraction studies of pristine as well as irradiated W/Ni multilayers show deterioration of the superlattice structure, whereas x-ray reflectivity (XRR) measurement reveals a nearly unaffected microstructure after irradiation. Analysis of the XRR data using 'Parratt's formalism' does show a significant increase of W/Ni interface roughness. Cross-sectional transmission electron microscopy (TEM) studies carried out in diffraction and imaging modes (including bright-field and dark-field imaging), show that at high irradiation dose the intralayer microstructure of Ni becomes nano-crystalline (1-2 nm). During these irradiation induced changes of the intralayer microstructure, the interlayer definition of the W and Ni layers still remains intact. The observed nano-recrystallization of Ni has been attributed to competition between low miscibility of the W/Ni interface and the ion-beam induced mixing kinetics.

  13. Irradiation with x-rays of the energy 18 MV induces radioactivity in transfusion blood: Proposal of a safe method using 6 MV.

    PubMed

    Frentzel, Katharina; Badakhshi, Harun

    2016-12-01

    To prevent a fatal transfusion-associated graft-versus-host disease, it is recommended to irradiate transfusion blood and blood components with ionizing radiation. Using x-rays from a linear accelerator of the radiotherapy department is an accepted alternative to gamma irradiation devices of the blood bank and to the orthovoltage units that are replacing the gamma irradiators today. However, the use of high energy x-rays may carry a potential risk of induced radioactivity. The objective of this study was to investigate the effect of two different energy levels, 6 and 18 MV, which are executed in routine clinical settings. The research question was if induced radioactivity occurs at one of these standard energy levels. The authors aimed to give a proposal for a blood irradiation procedure that certainly avoids induced radioactivity. For this study, the authors developed a blood bag phantom, irradiated it with x-ray energies of 6 and 18 MV, and measured the induced radioactivity in a well counter. Thereafter, the same irradiation and measuring procedure was performed with a unit of packed red blood cells. A feasible clinical procedure was developed using 6 MV and an acrylic box. With the irradiation planning system XiO, the authors generated an irradiation protocol for the linear accelerator Siemens ONCOR Anvant-Garde. Both measurement setups showed that there was induced radioactivity for 18 MV but not for 6 MV. The induced radioactivity for 18 MV was up to 190 times the background. This is significant and of clinical relevance especially since there are newborn and fetal blood recipients for whom every radiation exposure has to be strictly avoided. The irradiation of blood with x-rays from a linear accelerator of the radiotherapy department is safe and feasible, but by the current state of scientific knowledge, the authors recommend to use an x-ray energy of 6 MV or less to avoid induced radioactivity in transfusion blood.

  14. Accidental introductions are an important source of invasive plants in the continental United States.

    PubMed

    Lehan, Nora E; Murphy, Julia R; Thorburn, Lukas P; Bradley, Bethany A

    2013-07-01

    Preventing new plant invasions is critical for reducing large-scale ecological change. Most studies have focused on the deliberate introduction of nonnatives via the ornamental plant trade. However, accidental introduction may be an important source of nonnative, invasive plants. Using Web and literature searches, we compiled pathways of introduction to the United States for 1112 nonnative plants identified as invasive in the continental United States. We assessed how the proportion of accidentally and deliberately introduced invasive plants varies over time and space and by growth habit across the lower 48 states. Deliberate introductions of ornamentals are the primary source of invasive plants in the United States, but accidental introductions through seed contaminants are an important secondary source. Invasive forbs and grasses are the most likely to have arrived accidentally through seed contaminants, while almost all nonnative, invasive trees were introduced deliberately. Nonnative plants invading eastern states primarily arrived deliberately as ornamentals, while a high proportion of invasive plants in western states arrived accidentally as seed contaminants. Accidental introductions may be increasing in importance through time. Before 1850, 10 of 89 (11%) of invasive plants arrived accidentally. After 1900, 20 of 65 (31%) arrived accidentally. Recently enacted screening protocols and weed risk assessments aim to reduce the number of potentially invasive species arriving to the United States via deliberate introduction pathways. Increasing proportions of accidentally introduced invasive plants, particularly associated with contaminated seed imports across the western states, suggest that accidental introduction pathways also need to be considered in future regulatory decisions.

  15. Imitation of Intentional and Accidental Actions by Children with Autism

    ERIC Educational Resources Information Center

    D'Entremont, Barbara; Yazbek, Aimee

    2007-01-01

    To determine whether children with autism (CWA) would selectively imitate intentional, as opposed to accidental actions, an experimenter demonstrated either an "intentional" and an "accidental" action or two "intentional" actions on the same toy [Carpenter, Akhtar, & Tomasello ("1998a") "Infant Behavior and Development, 21," 315-330]. CWA tended…

  16. Orthopositronium study of positron-irradiation-induced surface defects in alumina powder

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dauwe, C.; Mbungu-Tsumbu

    1992-01-01

    Three-quantum-yield measurements and orthopositronium ({ital o}-Ps)-lifetime spectrometry at low temperatures are used to study the interaction of positronium with the surface in fine powders of aluminum oxide. It is found that electron and/or positron irradiation of the specimen induces surface defects which influence the positronium in three ways: (1) A surface positroniumlike bound state is created, (2) the fraction of {ital o}-Ps escaping from the particles is slightly inhibited, and (3) the escaped {ital o}-Ps is quenched into two-quantum decay upon collisions with the surface defects. It is found that the surface Ps state is not populated at the expensemore » of the interparticle Ps. The most likely surface defects are Al{sup 2+} or Al{sup 0} due to the migration of irradiation-induced interstitials. The techniques of long-lifetime spectrometry and of three-quantum-annihilation-rate measurement could be used to study both the diffusion of bulk defects to the surfaces, and the interactions of {ital o}-Ps to surface defects.« less

  17. Irradiation induced structural change in Mo 2Zr intermetallic phase

    DOE PAGES

    Gan, J.; Keiser, Jr., D. D.; Miller, B. D.; ...

    2016-05-14

    The Mo 2Zr phase has been identified as a major interaction product at the interface of U-10Mo and Zr. Transmission electron microscopy in-situ irradiation with Kr ions at 200 °C with doses up to 2.0E+16 ions/cm 2 was carried out to investigate the radiation stability of the Mo 2Zr. The Mo 2Zr undergoes a radiation-induced structural change, from a large cubic (cF24) to a small cubic (cI2), along with an estimated 11.2% volume contraction without changing its composition. The structural change begins at irradiation dose below 1.0E+14 ions/cm 2. Furthermore, the transformed Mo 2Zr phase demonstrates exceptional radiation tolerance withmore » the development of dislocations without bubble formation.« less

  18. RhNRG-1β Protects the Myocardium against Irradiation-Induced Damage via the ErbB2-ERK-SIRT1 Signaling Pathway

    PubMed Central

    Gu, Anxin; Jie, Yamin; Sun, Liang; Zhao, Shuping; E, Mingyan; You, Qingshan

    2015-01-01

    Radiation-induced heart disease (RIHD), which is a serious side effect of the radiotherapy applied for various tumors due to the inevitable irradiation of the heart, cannot be treated effectively using current clinical therapies. Here, we demonstrated that rhNRG-1β, an epidermal growth factor (EGF)-like protein, protects myocardium tissue against irradiation-induced damage and preserves cardiac function. rhNRG-1β effectively ameliorated irradiation-induced myocardial nuclear damage in both cultured adult rat-derived cardiomyocytes and rat myocardium tissue via NRG/ErbB2 signaling. By activating ErbB2, rhNRG-1β maintained mitochondrial integrity, ATP production, respiratory chain function and the Krebs cycle status in irradiated cardiomyocytes. Moreover, the protection of irradiated cardiomyocytes and myocardium tissue by rhNRG-1β was at least partly mediated by the activation of the ErbB2-ERK-SIRT1 signaling pathway. Long-term observations further showed that rhNRG-1β administered in the peri-irradiation period exerts continuous protective effects on cardiac pump function, the myocardial energy metabolism, cardiomyocyte volume and interstitial fibrosis in the rats receiving radiation via NRG/ErbB2 signaling. Our findings indicate that rhNRG-1β can protect the myocardium against irradiation-induced damage and preserve cardiac function via the ErbB2-ERK-SIRT1 signaling pathway. PMID:26332771

  19. Pulmonary anatomy and a case of unilateral aplasia in a common snapping turtle (Chelydra serpentina): developmental perspectives on cryptodiran lungs.

    PubMed

    Schachner, E R; Sedlmayr, J C; Schott, R; Lyson, T R; Sanders, R K; Lambertz, M

    2017-12-01

    The common snapping turtle (Chelydra serpentina) is a well studied and broadly distributed member of Testudines; however, very little is known concerning developmental anomalies and soft tissue pathologies of turtles and other reptiles. Here, we present an unusual case of unilateral pulmonary aplasia, asymmetrical carapacial kyphosis, and mild scoliosis in a live adult C. serpentina. The detailed three-dimensional (3D) anatomy of the respiratory system in both the pathological and normal adult C. serpentina, and a hatchling are visualized using computed tomography (CT), microCT, and 3D digital anatomical models. In the pathological turtle, the right lung consists of an extrapulmonary bronchus that terminates in a blind stump with no lung present. The left lung is hyperinflated relative to the normal adult, occupying the extra coelomic space facilitated by the unusual mid-carapacial kyphotic bulge. The bronchial tree of the left lung retains the overall bauplan of the normal specimens, with some minor downstream variation in the number of secondary airways. The primary difference between the internal pulmonary structure of the pathological individual and that of a normal adult is a marked increase in the surface area and density of the parenchymal tissue originating from the secondary airways, a 14.3% increase in the surface area to volume ratio. Despite this, the aplasia has not had an impact upon the ability of the turtle to survive; however, it did interfere with aquatic locomotion and buoyancy control under water. This turtle represents a striking example of a non-fatal congenital defect and compensatory visceral hypertrophy. © 2017 Anatomical Society.

  20. Experiences of Causing an Accidental Death: An Interpretative Phenomenological Analysis

    ERIC Educational Resources Information Center

    Rassool, Sara B.; Nel, Pieter W.

    2012-01-01

    Accidentally killing or feeling responsible for another person's death constitutes an event that is different from many typical traumatic stressors in that the responsibility for causing the trauma is located in the person themselves, rather than another person or persons. Research exploring the perspective of those who have accidentally caused a…

  1. Serum Proteome Analysis for Profiling Predictive Protein Markers Associated with the Severity of Skin Lesions Induced by Ionizing Radiation.

    PubMed

    Chaze, Thibault; Hornez, Louis; Chambon, Christophe; Haddad, Iman; Vinh, Joelle; Peyrat, Jean-Philippe; Benderitter, Marc; Guipaud, Olivier

    2013-07-10

    The finding of new diagnostic and prognostic markers of local radiation injury, and particularly of the cutaneous radiation syndrome, is crucial for its medical management, in the case of both accidental exposure and radiotherapy side effects. Especially, a fast high-throughput method is still needed for triage of people accidentally exposed to ionizing radiation. In this study, we investigated the impact of localized irradiation of the skin on the early alteration of the serum proteome of mice in an effort to discover markers associated with the exposure and severity of impending damage. Using two different large-scale quantitative proteomic approaches, 2D-DIGE-MS and SELDI-TOF-MS, we performed global analyses of serum proteins collected in the clinical latency phase (days 3 and 7) from non-irradiated and locally irradiated mice exposed to high doses of 20, 40 and 80 Gy which will develop respectively erythema, moist desquamation and necrosis. Unsupervised and supervised multivariate statistical analyses (principal component analysis, partial-least square discriminant analysis and Random Forest analysis) using 2D-DIGE quantitative protein data allowed us to discriminate early between non-irradiated and irradiated animals, and between uninjured/slightly injured animals and animals that will develop severe lesions. On the other hand, despite a high number of animal replicates, PLS-DA and Random Forest analyses of SELDI-TOF-MS data failed to reveal sets of MS peaks able to discriminate between the different groups of animals. Our results show that, unlike SELDI-TOF-MS, the 2D-DIGE approach remains a powerful and promising method for the discovery of sets of proteins that could be used for the development of clinical tests for triage and the prognosis of the severity of radiation-induced skin lesions. We propose a list of 15 proteins which constitutes a set of candidate proteins for triage and prognosis of skin lesion outcomes.

  2. Serum Proteome Analysis for Profiling Predictive Protein Markers Associated with the Severity of Skin Lesions Induced by Ionizing Radiation

    PubMed Central

    Chaze, Thibault; Hornez, Louis; Chambon, Christophe; Haddad, Iman; Vinh, Joelle; Peyrat, Jean-Philippe; Benderitter, Marc; Guipaud, Olivier

    2013-01-01

    The finding of new diagnostic and prognostic markers of local radiation injury, and particularly of the cutaneous radiation syndrome, is crucial for its medical management, in the case of both accidental exposure and radiotherapy side effects. Especially, a fast high-throughput method is still needed for triage of people accidentally exposed to ionizing radiation. In this study, we investigated the impact of localized irradiation of the skin on the early alteration of the serum proteome of mice in an effort to discover markers associated with the exposure and severity of impending damage. Using two different large-scale quantitative proteomic approaches, 2D-DIGE-MS and SELDI-TOF-MS, we performed global analyses of serum proteins collected in the clinical latency phase (days 3 and 7) from non-irradiated and locally irradiated mice exposed to high doses of 20, 40 and 80 Gy which will develop respectively erythema, moist desquamation and necrosis. Unsupervised and supervised multivariate statistical analyses (principal component analysis, partial-least square discriminant analysis and Random Forest analysis) using 2D-DIGE quantitative protein data allowed us to discriminate early between non-irradiated and irradiated animals, and between uninjured/slightly injured animals and animals that will develop severe lesions. On the other hand, despite a high number of animal replicates, PLS-DA and Random Forest analyses of SELDI-TOF-MS data failed to reveal sets of MS peaks able to discriminate between the different groups of animals. Our results show that, unlike SELDI-TOF-MS, the 2D-DIGE approach remains a powerful and promising method for the discovery of sets of proteins that could be used for the development of clinical tests for triage and the prognosis of the severity of radiation-induced skin lesions. We propose a list of 15 proteins which constitutes a set of candidate proteins for triage and prognosis of skin lesion outcomes. PMID:28250398

  3. Accidental degeneracies in nonlinear quantum deformed systems

    NASA Astrophysics Data System (ADS)

    Aleixo, A. N. F.; Balantekin, A. B.

    2011-09-01

    We construct a multi-parameter nonlinear deformed algebra for quantum confined systems that includes many other deformed models as particular cases. We demonstrate that such systems exhibit the property of accidental pairwise energy level degeneracies. We also study, as a special case of our multi-parameter deformation formalism, the extension of the Tamm-Dancoff cutoff deformed oscillator and the occurrence of accidental pairwise degeneracy in the energy levels of the deformed system. As an application, we discuss the case of a trigonometric Rosen-Morse potential, which is successfully used in models for quantum confined systems, ranging from electrons in quantum dots to quarks in hadrons.

  4. [Thrombopenia and radial aplasia: 2 cases with platelet function and ultrastructural studies of megakaryocytes and platelets (author's transl)].

    PubMed

    Juhan, I; Bayle, J; Mattei, J F; Thevenieau, D; Perrimond, H; Muratore, R

    1979-10-01

    The authors report on two cases of congenital thrombopenia with radial aplasia. Both children display several formative abnormalities and a mild thrombopenia; hemorragic manifestations occurred in the first case only. Megacryoblastic to platelets series, as studied with electronic microscopy, show small-sized, "microcytic" and hypogranular megacaryocytes, displaying a maturative disorder (dysmegacaryocytopoiesis). In functional studies, platelets of the first patient show an imperfect nucleotidic release and do not agregate normally with ristocetin. The second case exhibits mostly a PF3 reduction. The variety of expression of the megacaryocytic-platelets disorders appears likewise in the squelettal and visceral malformations. The whole disorder could be ascribed to a pleiotropic abnormal gene with a variable expressivity.

  5. Ion irradiation induced defect evolution in Ni and Ni-based FCC equiatomic binary alloys

    DOE PAGES

    Jin, Ke; Zhang, Yanwen; Bei, Hongbin

    2015-09-09

    In order to explore the chemical effects on radiation response of alloys with multi-principal elements, defect evolution under Au ion irradiation was investigated in the elemental Ni, equiatomic NiCo and NiFe alloys. Single crystals were successfully grown in an optical floating zone furnace and their (100) surfaces were irradiated with 3 MeV Au ions at fluences ranging from 1 × 10 13 to 5 × 10 15 ions cm –2 at room temperature. The irradiation-induced defect evolution was analyzed by using ion channeling technique. Experiment shows that NiFe is more irradiation-resistant than NiCo and pure Ni at low fluences. Withmore » continuously increasing the ion fluences, damage level is eventually saturated for all materials but at different dose levels. The saturation level in pure Ni appears at relatively lower irradiation fluence than the alloys, suggesting that damage accumulation slows down in the alloys. Here, under high-fluence irradiations, pure Ni has wider damage ranges than the alloys, indicating that defects in pure Ni have high mobility.« less

  6. Investigation on Large Molecule Permeation through Liposome Lipid Bilayer Induced by Microplasma Irradiation

    NASA Astrophysics Data System (ADS)

    Nagaiwa, Hidenori; Aibara, Daijiro; Ikeda, Yoshihisa; Motomura, Hideki; Kido, Yugo; Satoh, Susumu; Tachibana, Kunihide; Jinno, Masahumi

    2015-09-01

    The authors have been developing a novel gene transfection method using microplasma irradiation. In order to clarify the mechanism of large molecule permeation process through the lipid bilayer, plasma induced outflow of hydrophilic fluorescent dye molecules, which were encapsulated in the liposome, was observed. By microplasma irradiation on the liposome suspension, the dyes flowed out from the inside of the liposomes. The outflow of the dyes was enhanced by longer plasma irradiation time. Investigation of the outflow mechanism, i.e. permeation enhancement of the lipid bilayer or burst of the liposome, is under progress. This work was partly supported by JSPS KAKENHI Grant-in-Aid for Scientific Research on Innovative Areas (Number 25108509,15H00896) and a grant from Ehime University.

  7. On the Detectability of Acoustic Waves Induced Following Irradiation by a Radiotherapy Linear Accelerator.

    PubMed

    Hickling, Susannah; Leger, Pierre; El Naqa, Issam

    2016-02-11

    Irradiating an object with a megavoltage photon beam generated by a clinical radiotherapy linear accelerator (linac) induces acoustic waves through the photoacoustic effect. The detection and characterization of such acoustic waves has potential applications in radiation therapy dosimetry. The purpose of this work was to gain insight into the properties of such acoustic waves by simulating and experimentally detecting them in a well-defined system consisting of a metal block suspended in a water tank. A novel simulation workflow was developed by combining radiotherapy Monte Carlo and acoustic wave transport simulation techniques. Different set-up parameters such as photon beam energy, metal block depth, metal block width, and metal block material were varied, and the simulated and experimental acoustic waveforms showed the same relative amplitude trends and frequency variations for such setup changes. The simulation platform developed in this work can easily be extended to other irradiation situations, and will be an invaluable tool for developing a radiotherapy dosimetry system based on the detection of the acoustic waves induced following linear accelerator irradiation.

  8. Gamma irradiation induces acetylcholine-evoked, endothelium-independent relaxation and activatesk-channels of isolated pulmonary artery of rats

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eder, Veronique; Gautier, Mathieu; Boissiere, Julien

    2004-12-01

    Purpose: To test the effects of irradiation (R*) on the pulmonary artery (PA). Methods and materials: Isolated PA rings were submitted to gamma irradiation (cesium, 8 Gy/min{sup -1}) at doses of 20 Gy-140 Gy. Rings were placed in an organ chamber, contracted with serotonin (10{sup -4} M 5-hydroxytryptamine [5-HT]), then exposed to acetylcholine (ACh) in incremental concentrations. Smooth muscle cell (SMC) membrane potential was measured with microelectrodes. Results: A high dose of irradiation (60 Gy) increased 5HT contraction by 20%, whereas lower (20 Gy) doses slightly decreased it compared with control. In the absence of the endothelium, 5-HT precontracted ringsmore » exposed to 20 Gy irradiation developed a dose-dependent relaxation induced by acetylcholine (EI-ACh) with maximal relaxation of 60 {+-} 17% (n = 13). This was totally blocked by L-NAME (10{sup -4} M), partly by 7-nitro indazole; it was abolished by hypoxia and iberiotoxin, decreased by tetra-ethyl-ammonium, and not affected by free radical scavengers. In irradiated rings, hypoxia induced a slight contraction which was never observed in control rings. No differences in SMC membrane potential were observed between irradiated and nonirradiated PA rings. Conclusion: Irradiation mediates endothelium independent relaxation by a mechanism involving the nitric oxide pathway and K-channels.« less

  9. Model of photoinduced structural change induced by THz pulse irradiation

    NASA Astrophysics Data System (ADS)

    Ishida, Kunio; Nasu, Keiichiro

    Recently intense optical pulses with THz frequency have been obtained, and it is of interest to study the effect of irradiated THz pulses on electronic systems. We theoretically study the photoinduced cooperative dynamics triggered by irradiation of THz pulses. We employed a model of two-level localized electrons coupled with an optical phonon mode taking into account the nonadiabaticity of the electron dynamics, and solved the time-dependent Schrödinger equation numerically. We consider the cases in which the THz pulses create phonons near the surface of the system, and pursue the electronic transitions induced by the propagation of the phonons. We found that they are able to induce excited-state domain growth, and that the interference between them plays an important role in the growth dynamics. Hence, the domain growth is affected by the geometry of the surface of the system, which is different from the photoinduced structural change by visible/UV pulses. We also show that the nonadiabatic/adiabatic electronic transitions should be taken into account though the domain growth mainly proceeds on the ground-state potential energy surfaces(PESs). In other words, the energy level/structure of excited-state PESs are relevant to the domain-growth dynamics.

  10. Protective effect of curcumin against ultraviolet A irradiation-induced photoaging in human dermal fibroblasts

    PubMed Central

    Liu, Xiaoming; Zhang, Ruizhi; Shi, Haixia; Li, Xiaobo; Li, Yanhong; Taha, Ahmad; Xu, Chunxing

    2018-01-01

    Ultraviolet (UV) radiation induces DNA damage, oxidative stress, and inflammatory processes in skin, resulting in photoaging. Natural botanicals have gained considerable attention due to their beneficial protection against the harmful effects of UV irradiation. The present study aimed to evaluate the ability of curcumin (Cur) to protect human dermal fibroblasts (HDFs) against ultraviolet A (UVA)-induced photoaging. HDFs were treated with 0–10 µM Cur for 2 h and subsequently exposed to various intensities of UVA irradiation. The cell viability and apoptotic rate of HDFs were investigated by MTT and flow cytometry assays, respectively. The effect of UVA and Cur on the formation of reactive oxygen species (ROS), malondialdehyde levels, which are an indicator of ROS, and the levels/activity of antioxidative defense proteins, including glutathione, superoxide dismutase and catalase, were evaluated using 2′,7′-dichlorofluorescin diacetate and commercial assay kits. Furthermore, western blotting was performed to determine the levels of proteins associated with endoplasmic reticulum (ER) stress, the apoptotic pathway, inflammation and the collagen synthesis pathway. The results demonstrated that Cur reduced the accumulation of ROS and restored the activity of antioxidant defense enzymes, indicating that Cur minimized the damage induced by UVA irradiation in HDFs. Furthermore, western blot analysis demonstrated that Cur may attenuate UVA-induced ER stress, inflammation and apoptotic signaling by downregulating the protein expression of glucose-regulated protein 78, C/EBP-homologous protein, nuclear factor-κB and cleaved caspase-3, while upregulating the expression of Bcl-2. Additionally, it was demonstrated that Cur may regulate collagen metabolism by decreasing the protein expression of matrix metalloproteinase (MMP)-1 and MMP-3, and may promote the repair of cells damaged as a result of UVA irradiation through increasing the protein expression of transforming

  11. Novel Radiomitigator for Radiation-Induced Bone Loss

    NASA Technical Reports Server (NTRS)

    Schreurs, A-S; Shirazi-fard, Y.; Terada, M.; Alwood, J. S.; Steczina, S.; Medina, C.; Tahimic, C. G. T.; Globus, R. K.

    2016-01-01

    Radiation-induced bone loss can occur with radiotherapy patients, accidental radiation exposure and during long-term spaceflight. Bone loss due to radiation is due to an early increase in oxidative stress, inflammation and bone resorption, resulting in an imbalance in bone remodeling. Furthermore, exposure to high-Linear Energy Transfer (LET) radiation will impair the bone forming progenitors and reduce bone formation. Radiation can be classified as high-LET or low-LET based on the amount of energy released. Dried Plum (DP) diet prevents bone loss in mice exposed to total body irradiation with both low-LET and high-LET radiation. DP prevents the early radiation-induced bone resorption, but furthermore, we show that DP protects the bone forming osteoblast progenitors from high-LET radiation. These results provide insight that DP re-balances the bone remodeling by preventing resorption and protecting the bone formation capacity. This data is important considering that most of the current osteoporosis treatments only block the bone resorption but do not protect bone formation. In addition, DP seems to act on both the oxidative stress and inflammation pathways. Finally, we have preliminary data showing the potential of DP to be radio-protective at a systemic effect and could possible protect other tissues at risk of total body-irradiation such as skin, brain and heart.

  12. Potential Protective Effects of Ursolic Acid against Gamma Irradiation-Induced Damage Are Mediated through the Modulation of Diverse Inflammatory Mediators

    PubMed Central

    Wang, Hong; Sim, Meng-Kwoon; Loke, Weng Keong; Chinnathambi, Arunachalam; Alharbi, Sulaiman Ali; Tang, Feng Ru; Sethi, Gautam

    2017-01-01

    This study was aimed to evaluate the possible protective effects of ursolic acid (UA) against gamma radiation induced damage both in vitro as well as in vivo. It was observed that the exposure to gamma radiation dose- and time-dependently caused a significant decrease in the cell viability, while the treatment of UA attenuated this cytotoxicity. The production of free radicals including reactive oxygen species (ROS) and NO increased significantly post-irradiation and further induced lipid peroxidation and oxidative DNA damage in cells. These deleterious effects could also be effectively blocked by UA treatment. In addition, UA also reversed gamma irradiation induced inflammatory responses, as indicated by the decreased production of TNF-α, IL-6, and IL-1β. NF-κB signaling pathway has been reported to be a key mediator involved in gamma radiation-induced cellular damage. Our results further demonstrated that gamma radiation dose- and time-dependently enhanced NF-κB DNA binding activity, which was significantly attenuated upon UA treatment. The post-irradiation increase in the expression of both phospho-p65, and phospho-IκBα was also blocked by UA. Moreover, the treatment of UA was found to significantly prolong overall survival in mice exposed to whole body gamma irradiation, and reduce the excessive inflammatory responses. Given its radioprotective efficacy as described here, UA as an antioxidant and NF-κB pathway blocker, may function as an important pharmacological agent in protecting against gamma irradiation-induced injury. PMID:28670276

  13. Structural changes of Ti3SiC2 induced by helium irradiation with different doses

    NASA Astrophysics Data System (ADS)

    Zhang, Hongliang; Su, Ranran; Shi, Liqun; O'Connor, Daryl J.; Wen, Haiming

    2018-03-01

    In this study, the microstructure changes of Ti3SiC2 MAX phase material induced by helium irradiation and evolution with a sequence of different helium irradiation doses of 5 × 1015, 1 × 1016, 5 × 1016 and 1 × 1017 cm-2 at room temperature (RT) were characterized with grazing incidence X-ray diffraction (GIXRD) and Raman spectra analysis. The irradiation damage process of Ti3SiC2 can be roughly divided into three stages according to the level of helium irradiation dose: (1) for a low damage dose, only crystal and damaged Ti3SiC2 exit; (2) at a higher irradiation dose, there is some damaged TiC phase additionally; (3) with a much higher irradiation dose, crystal TiC phase could be found inside the samples as well. Moreover, the 450 °C 5 × 1016 cm-2 helium irradiation on Ti3SiC2 has confirmed that Ti3SiC2 has much higher irradiation tolerance at higher temperature, which implies that Ti3SiC2 could be a potential future structural and fuel coating material working at high temperature environments.

  14. Individual housing-based socioeconomic status predicts risk of accidental falls among adults.

    PubMed

    Ryu, Euijung; Juhn, Young J; Wheeler, Philip H; Hathcock, Matthew A; Wi, Chung-Il; Olson, Janet E; Cerhan, James R; Takahashi, Paul Y

    2017-07-01

    Accidental falls are a major public health concern among people of all ages. Little is known about whether an individual-level housing-based socioeconomic status measure is associated with the risk of accidental falls. Among 12,286 Mayo Clinic Biobank participants residing in Olmsted County, Minnesota, subjects who experienced accidental falls between the biobank enrollment and September 2014 were identified using ICD-9 codes evaluated at emergency departments. HOUSES (HOUsing-based Index of SocioEconomic Status), a socioeconomic status measure based on individual housing features, was also calculated. Cox regression models were utilized to assess the association of the HOUSES (in quartiles) with accidental fall risk. Seven hundred eleven (5.8%) participants had at least one emergency room visit due to an accidental fall during the study period. Subjects with higher HOUSES were less likely to experience falls in a dose-response manner (hazard ratio: 0.58; 95% confidence interval: 0.44-0.76 for comparing the highest to the lowest quartile). In addition, the HOUSES was positively associated with better health behaviors, social support, and functional status. The HOUSES is inversely associated with accidental fall risk requiring emergency care in a dose-response manner. The HOUSES may capture falls-related risk factors through housing features and socioeconomic status-related psychosocial factors. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Procedures, placement, and risks of further abuse after Munchausen syndrome by proxy, non-accidental poisoning, and non-accidental suffocation

    PubMed Central

    Davis, P; McClure, R; Rolfe, K; Chessman, N; Pearson, S; Sibert, J; Meadow, R

    1998-01-01

    OBJECTIVES—To investigate outcome, management, and prevention in Munchausen syndrome by proxy, non-accidental poisoning, and non-accidental suffocation.
DESIGN—Ascertainment through British Paediatric Surveillance Unit and questionnaires to responding paediatricians.
SETTING—The UK and Republic of Ireland, September 1992 to August 1994.
SUBJECTS—Children under 14 years diagnosed with the above.
MAIN OUTCOME MEASURES—Placement and child protection measures for victims and siblings; morbidity and reabuse rates for victims; abuse of siblings; prosecution of perpetrators.
RESULTS—Outcome data for 119 with median follow up of 24 months (range 12 to 44 months). No previously diagnosed factitious disease was found to have been caused by genuine disease. Forty six children were allowed home without conditions at follow up. Children who had suffered from suffocation, non-accidental poisoning, direct harm, and those under 5 years were less likely to go home.
 Twenty seven (24%) children still had symptoms or signs as a result of the abuse at follow up; 108/120 were originally on a child protection register and 35/111 at follow up. Twenty nine per cent (34/118) of the perpetrators had been prosecuted and most convicted; 17% of the milder cases of Munchausen syndrome by proxy allowed home were reabused. Evidence in siblings suggests that in 50% of families with a suffocated child and 40% with non-accidental poisoning there would be further abuse, some fatal.
CONCLUSIONS—This type of abuse is severe with high mortality, morbidity, family disruption, reabuse, and harm to siblings. A very cautious approach for child protection with reintroduction to home only if circumstances are especially favourable is advised. Paediatric follow up by an expert in child protection should also occur.

 PMID:9613350

  16. Ion irradiation-induced crystal structure changes in inverse spinel MgIn 2O 4

    DOE PAGES

    Tang, Ming; Valdez, James A.; Wang, Yongqiang; ...

    2016-07-29

    We performed 400 keV Ne and 200 keV He ion irradiations on fully inverse MgIn 2O 4 samples at cryogenic temperature (~ 77 K), in order to examine the influence of radiation-induced cation disordering on crystal structure. In the case of MgIn 2O 4 samples irradiated with Ne ions to a peak displacement damage dose of 4 displacements per atom (dpa), a spinel-to-rocksalt phase transformation was observed. Conversely, for MgIn 2O 4 samples irradiated with He ions to a peak displacement damage dose of 5 dpa, the only observed structural effect involved cation rearrangements from an inverse to a “random”more » spinel structure.« less

  17. Modeling thermal and irradiation-induced swelling effects on the integrity of Ti 3 SiC 2 /SiC joints

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nguyen, Ba Nghiep; Henager, Charles H.; Kurtz, Richard J.

    Previously, results for CVD-SiC joints created using solid state displacement reactions to form a dual-phase SiC/MAX phase irradiated at 800°C and 5 dpa indicated some extent of cracking in the joint and along the CVD-SiC/joint interface. This paper elucidates the origin of cracking by thermomechanical modeling combined with irradiation-induced swelling effects using a continuum damage approach with support of micromechanical modeling. Three irradiation temperatures (400°C, 500°C and 800°C) are considered assuming experimental irradiation doses in a range leading to saturation swelling in SiC. The analyses indicate that a SiC/MAX joint heated to 400°C fails during irradiation-induced swelling at this temperaturemore » while it experiences some damage after being heated to 500°C and irradiated at the same temperature. However, it fails during cooling from 500°C to room temperature. The joint experiences minor damage when heated to and irradiated at 800°C but does not fail after cooling. The prediction agrees with the experimental findings available for this case.« less

  18. Protective effects of melatonin against 12C6+ beam irradiation-induced oxidative stress and DNA injury in the mouse brain

    NASA Astrophysics Data System (ADS)

    Wu, Z. H.; Zhang, H.; Wang, X. Y.; Yang, R.; Liu, B.; Liu, Y.; Zhao, W. P.; Feng, H. Y.; Xue, L. G.; Hao, J. F.; Niu, B. T.; Wang, Z. H.

    2012-01-01

    The purpose of this experiment was to estimate the protective effects of melatonin against radiation-induced brain damages in mice induced by heavy ion beams. Kun-Ming mice were randomly divided into five groups: normal control group, irradiation control group, and three different doses of melatonin (5, 10, and 20 mg/kg, i.p.) treated groups. Apart from the normal control group, the other four groups were exposed to whole-body 4.0 Gy carbon ion beam irradiation (approximately 0.5 Gy/min) after i.p. administration of normal saline or melatonin 1 h before irradiation. The oxidative redox status of brain tissue was assessed by measurement of malondiadehyde (MDA) levels, total superoxide dismutase (T-SOD), cytosolic superoxide dismutase (Cu/ZnSOD, SOD1) and mitochondrial superoxide dismutase (MnSOD, SOD2) activities at 8 h after irradiation. DNA damages were determined using the Comet assay and apoptosis and cell cycle distribution were detected by flow cytometric analyses. A dramatic dose-dependent decrease in MDA levels, tail moment, rates of tailing cells, and apoptosis, and a dose-dependent increase in T-SOD and SOD2 activities, in brain tissues in the melatonin-treated groups were detected compared with the irradiation only group. Furthermore, flow cytometric analysis demonstrated that the percentage of brain cells in the G0/G1 phase decreased significantly, while those in the S and G2/M stage increased dramatically, with mice pretreated with melatonin compared to the irradiation control group. These data indicate that melatonin has protective effects against irradiation-induced brain injury, and that its underlying protective mechanisms may relate to modulation of oxidative stress induced by heavy ionirradiation.

  19. Irradiation-induced β to α SiC transformation at low temperature

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parish, Chad M.; Koyanagi, Takaaki; Kondo, Sosuke

    Here, we observed that β-SiC, neutron irradiated to 9 dpa (displacements per atom) at ≈1440 °C, began transforming to α-SiC, with radiation-induced Frank dislocation loops serving as the apparent nucleation sites. 1440 °C is a far lower temperature than usual β → α phase transformations in SiC. SiC is considered for applications in advanced nuclear systems, as well as for electronic or spintronic applications requiring ion irradiation processing. β-SiC, preferred for nuclear applications, is metastable and undergoes a phase transformation at high temperatures (typically 2000 °C and above). Nuclear reactor concepts are not expected to reach the very high temperaturesmore » for thermal transformation. However, our results indicate incipient β → α phase transformation, in the form of small (~5–10 nm) pockets of α-SiC forming in the β matrix. In service transformation could degrade structural stability and fuel integrity for SiC-based materials operated in this regime. However, engineering this transformation deliberately using ion irradiation could enable new electronic applications.« less

  20. Irradiation-induced β to α SiC transformation at low temperature

    DOE PAGES

    Parish, Chad M.; Koyanagi, Takaaki; Kondo, Sosuke; ...

    2017-04-26

    Here, we observed that β-SiC, neutron irradiated to 9 dpa (displacements per atom) at ≈1440 °C, began transforming to α-SiC, with radiation-induced Frank dislocation loops serving as the apparent nucleation sites. 1440 °C is a far lower temperature than usual β → α phase transformations in SiC. SiC is considered for applications in advanced nuclear systems, as well as for electronic or spintronic applications requiring ion irradiation processing. β-SiC, preferred for nuclear applications, is metastable and undergoes a phase transformation at high temperatures (typically 2000 °C and above). Nuclear reactor concepts are not expected to reach the very high temperaturesmore » for thermal transformation. However, our results indicate incipient β → α phase transformation, in the form of small (~5–10 nm) pockets of α-SiC forming in the β matrix. In service transformation could degrade structural stability and fuel integrity for SiC-based materials operated in this regime. However, engineering this transformation deliberately using ion irradiation could enable new electronic applications.« less

  1. Enhanced Lithium-Induced Brain Recovery Following Cranial Irradiation Is Not Impeded by Inflammation

    PubMed Central

    Malaterre, Jordane; McPherson, Cameron S.; Denoyer, Delphine; Lai, Emily; Hagekyriakou, Jim; Lightowler, Sally; Shudo, Koishi; Ernst, Matthias; Ashley, David M.; Short, Jennifer L.; Wheeler, Greg

    2012-01-01

    Radiation-induced brain injury occurs in many patients receiving cranial radiation therapy, and these deleterious effects are most profound in younger patients. Impaired neurocognitive functions in both humans and rodents are associated with inflammation, demyelination, and neural stem cell dysfunction. Here we evaluated the utility of lithium and a synthetic retinoid receptor agonist in reducing damage in a model of brain-focused irradiation in juvenile mice. We found that lithium stimulated brain progenitor cell proliferation and differentiation following cranial irradiation while also preventing oligodendrocyte loss in the dentate gyrus of juvenile mice. In response to inflammation induced by radiation, which may have encumbered the optimal reparative action of lithium, we used the anti-inflammatory synthetic retinoid Am80 that is in clinical use in the treatment of acute promyelocytic leukemia. Although Am80 reduced the number of cyclooxygenase-2-positive microglial cells following radiation treatment, it did not enhance lithium-induced neurogenesis recovery, and this alone was not significantly different from the effect of lithium on this proinflammatory response. Similarly, lithium was superior to Am80 in supporting the restoration of new doublecortin-positive neurons following irradiation. These data suggest that lithium is superior in its restorative effects to blocking inflammation alone, at least in the case of Am80. Because lithium has been in routine clinical practice for 60 years, these preclinical studies indicate that this drug might be beneficial in reducing post-therapy late effects in patients receiving cranial radiotherapy and that blocking inflammation in this context may not be as advantageous as previously suggested. PMID:23197851

  2. Depletion of Securin Induces Senescence After Irradiation and Enhances Radiosensitivity in Human Cancer Cells Regardless of Functional p53 Expression

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen Wenshu; Yu Yichu; Lee Yijang

    2010-06-01

    Purpose: Radiotherapy is one of the best choices for cancer treatment. However, various tumor cells exhibit resistance to irradiation-induced apoptosis. The development of new strategies to trigger cancer cell death besides apoptosis is necessary. This study investigated the role of securin in radiation-induced apoptosis and senescence in human cancer cells. Methods and Materials: Cell survival was determined using clonogenic assays. Western blot analysis was used to analyze levels of securin, caspase-3, PARP, p53, p21, Rb, gamma-H2AX, and phospho-Chk2. Senescent cells were analyzed using a beta-galactosidase staining assay. A securin-expressed vector (pcDNA-securin) was stably transfected into securin-null HCT116 cells. Securin genemore » knockdown was performed by small interfering RNA and small hairpin RNA in HCT116 and MDA-MB-231 cells, respectively. Results: Radiation was found to induce apoptosis in securin wild type HCT116 cells but induced senescence in securin-null cells. Restoration of securin reduced senescence and increased cell survival in securin-null HCT116 cells after irradiation. Radiation-induced gamma-H2AX and Chk2 phosphorylation were induced transiently in securin-wild-type cells but exhibited sustained activation in securin-null cells. Securin gene knockdown switches irradiation-induced apoptosis to senescence in both HCT116 p53-null and MDA-MB-231 cells. Conclusions: Our results demonstrated that the level of securin expression plays a determining role in the radiosensitivity and fate of cells. Depletion of securin impairs DNA repair after irradiation, increasing DNA damage and promoting senescence in the residual surviving cells regardless of functional p53 expression. The knockdown of securin may contribute to a novel radiotherapy protocol for the treatment of human cancer cells that are resistant to irradiation.« less

  3. Synchrotron microbeam irradiation induces neutrophil infiltration, thrombocyte attachment and selective vascular damage in vivo

    PubMed Central

    Brönnimann, Daniel; Bouchet, Audrey; Schneider, Christoph; Potez, Marine; Serduc, Raphaël; Bräuer-Krisch, Elke; Graber, Werner; von Gunten, Stephan; Laissue, Jean Albert; Djonov, Valentin

    2016-01-01

    Our goal was the visualizing the vascular damage and acute inflammatory response to micro- and minibeam irradiation in vivo. Microbeam (MRT) and minibeam radiation therapies (MBRT) are tumor treatment approaches of potential clinical relevance, both consisting of parallel X-ray beams and allowing the delivery of thousands of Grays within tumors. We compared the effects of microbeams (25–100 μm wide) and minibeams (200–800 μm wide) on vasculature, inflammation and surrounding tissue changes during zebrafish caudal fin regeneration in vivo. Microbeam irradiation triggered an acute inflammatory response restricted to the regenerating tissue. Six hours post irradiation (6 hpi), it was infiltrated by neutrophils and fli1a+ thrombocytes adhered to the cell wall locally in the beam path. The mature tissue was not affected by microbeam irradiation. In contrast, minibeam irradiation efficiently damaged the immature tissue at 6 hpi and damaged both the mature and immature tissue at 48 hpi. We demonstrate that vascular damage, inflammatory processes and cellular toxicity depend on the beam width and the stage of tissue maturation. Minibeam irradiation did not differentiate between mature and immature tissue. In contrast, all irradiation-induced effects of the microbeams were restricted to the rapidly growing immature tissue, indicating that microbeam irradiation could be a promising tumor treatment tool. PMID:27640676

  4. Synchrotron microbeam irradiation induces neutrophil infiltration, thrombocyte attachment and selective vascular damage in vivo.

    PubMed

    Brönnimann, Daniel; Bouchet, Audrey; Schneider, Christoph; Potez, Marine; Serduc, Raphaël; Bräuer-Krisch, Elke; Graber, Werner; von Gunten, Stephan; Laissue, Jean Albert; Djonov, Valentin

    2016-09-19

    Our goal was the visualizing the vascular damage and acute inflammatory response to micro- and minibeam irradiation in vivo. Microbeam (MRT) and minibeam radiation therapies (MBRT) are tumor treatment approaches of potential clinical relevance, both consisting of parallel X-ray beams and allowing the delivery of thousands of Grays within tumors. We compared the effects of microbeams (25-100 μm wide) and minibeams (200-800 μm wide) on vasculature, inflammation and surrounding tissue changes during zebrafish caudal fin regeneration in vivo. Microbeam irradiation triggered an acute inflammatory response restricted to the regenerating tissue. Six hours post irradiation (6 hpi), it was infiltrated by neutrophils and fli1a(+) thrombocytes adhered to the cell wall locally in the beam path. The mature tissue was not affected by microbeam irradiation. In contrast, minibeam irradiation efficiently damaged the immature tissue at 6 hpi and damaged both the mature and immature tissue at 48 hpi. We demonstrate that vascular damage, inflammatory processes and cellular toxicity depend on the beam width and the stage of tissue maturation. Minibeam irradiation did not differentiate between mature and immature tissue. In contrast, all irradiation-induced effects of the microbeams were restricted to the rapidly growing immature tissue, indicating that microbeam irradiation could be a promising tumor treatment tool.

  5. Accidental fetal lacerations during cesarean delivery: experience in an Italian level III university hospital.

    PubMed

    Dessole, Salvatore; Cosmi, Erich; Balata, Antonio; Uras, Luisa; Caserta, Donatella; Capobianco, Giampiero; Ambrosini, Guido

    2004-11-01

    The purpose of this study was to investigate the incidence, type, location, and risk factors of accidental fetal lacerations during cesarean delivery. Total deliveries, cesarean deliveries, and neonatal records for documented accidental fetal lacerations were reviewed retrospectively in our level III university hospital. The gestational age, the presenting part of the fetus, the cesarean delivery indication, the type of incision, and the surgeon who performed the procedure were recorded. Cesarean deliveries were divided into scheduled, unscheduled, and emergency procedures. Fetal lacerations were divided into mild, moderate, and severe. Neonatal follow-up examinations regarding laceration sequelae were available for 6 months. Of 14926 deliveries, 3108 women were delivered by cesarean birth (20.82%). Neonatal records documented 97 accidental fetal lacerations. Of these accidental lacerations, 94 were mild; 2 were moderate, and 1 was severe. The overall rate of accidental fetal laceration per cesarean delivery was 3.12%; the accidental laceration rate in the cohort of fetuses was 2.46%. The crude odds ratios were 0.34 for scheduled procedures, 0.57 for unscheduled procedures, and 1.7 for emergency procedures. The risk for fetal accidental lacerations was higher in fetuses who underwent emergency cesarean birth and lower for unscheduled and scheduled cesarean births (P < .001). Fetal accidental laceration may occur during cesarean delivery; the incidence is significantly higher during emergency cesarean delivery compared with elective procedures. The patient should be counseled about the occurrence of fetal laceration during cesarean delivery to avoid litigation.

  6. Hemodialysis as a treatment of severe accidental hypothermia.

    PubMed

    Caluwé, Rogier; Vanholder, Raymond; Dhondt, Annemieke

    2010-03-01

    We describe a case of severe accidental hypothermia (core body temperature 23.2 degrees C) successfully treated with hemodialysis in a diabetic patient with preexisting renal insufficiency. Consensus exists about cardiopulmonary bypass as the treatment of choice in cases of severe accidental hypothermia with cardiac arrest. Prospective randomized controlled trials comparing the different rewarming modalities for hemodynamically stable patients with hypothermia, however, are lacking. In our opinion, the choice of a rewarming technique should be patient tailored, knowing that hemodialysis is an efficient, minimally invasive, and readily available technique with the advantage of providing electrolyte support.

  7. A descriptive study of accidental skeletal injuries and non-accidental skeletal injuries of child maltreatment.

    PubMed

    Ghanem, Maha A H; Moustafa, Tarek A; Megahed, Haidy M; Salama, Naglaa; Ghitani, Sara A

    2018-02-01

    Lack of awareness and recognition of child maltreatment is the major reason behind underreporting. All victims often interact with the health care system for routine or emergency care. In several research works, non-accidental fractures are the second most common injury in maltreated children and it is represented up to one-third of cases. To determine the incidence of different types of accidental and non-accidental skeletal injuries among children, estimate the severity of injuries according to the modified injury severity score and to determine the degree of fractures either closed or opened (Gustiloe-Anderson open fracture classification). Moreover, identifying fractures resulting from child abuse and neglect. This aimed for early recognition of non-accidental nature of fractures in child maltreatment that can prevent further morbidity and mortality. A descriptive study was carried out on all children (109) with skeletal injuries who were admitted to both Main Alexandria and El-Hadara Orthopedic and Traumatology University Hospitals during six months. History, physical examination and investigations were done for the patients. A detailed questionnaire was taken to diagnose child abuse and neglect. Gustiloe-Anderson open fracture classification was used to estimate the degree of open fractures. Out of 109 children, twelve cases (11%) were categorized as child maltreatment. One case was physical abuse, eight cases (7.3%) were child neglect and three cases (2.8%) were labour exploitation. Road traffic accidents (RTA) was the commonest cause of skeletal injuries followed by falling from height. Regarding falls, they included 4 cases of stair falls in neglected children and another four cases of falling from height (balcony/window). The remaining 36 cases of falls were accidental. The skeletal injuries were in the form of fractures in 99 cases, dislocation in two cases, both fracture and/or dislocation in three cases, and bone deformity from brachial plexus injury

  8. 21 CFR 369.9 - General warnings re accidental ingestion by children.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 5 2012-04-01 2012-04-01 false General warnings re accidental ingestion by... SERVICES (CONTINUED) DRUGS FOR HUMAN USE INTERPRETATIVE STATEMENTS RE WARNINGS ON DRUGS AND DEVICES FOR OVER-THE-COUNTER SALE Definitions and Interpretations § 369.9 General warnings re accidental ingestion...

  9. 21 CFR 369.9 - General warnings re accidental ingestion by children.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false General warnings re accidental ingestion by... SERVICES (CONTINUED) DRUGS FOR HUMAN USE INTERPRETATIVE STATEMENTS RE WARNINGS ON DRUGS AND DEVICES FOR OVER-THE-COUNTER SALE Definitions and Interpretations § 369.9 General warnings re accidental ingestion...

  10. Solar ultraviolet irradiation induces decorin degradation in human skin likely via neutrophil elastase.

    PubMed

    Li, Yong; Xia, Wei; Liu, Ying; Remmer, Henriette A; Voorhees, John; Fisher, Gary J

    2013-01-01

    Exposure of human skin to solar ultraviolet (UV) irradiation induces matrix metalloproteinase-1 (MMP-1) activity, which degrades type I collagen fibrils. Type I collagen is the most abundant protein in skin and constitutes the majority of skin connective tissue (dermis). Degradation of collagen fibrils impairs the structure and function of skin that characterize skin aging. Decorin is the predominant proteoglycan in human dermis. In model systems, decorin binds to and protects type I collagen fibrils from proteolytic degradation by enzymes such as MMP-1. Little is known regarding alterations of decorin in response to UV irradiation. We found that solar-simulated UV irradiation of human skin in vivo stimulated substantial decorin degradation, with kinetics similar to infiltration of polymorphonuclear (PMN) cells. Proteases that were released from isolated PMN cells degraded decorin in vitro. A highly selective inhibitor of neutrophil elastase blocked decorin breakdown by proteases released from PMN cells. Furthermore, purified neutrophil elastase cleaved decorin in vitro and generated fragments with similar molecular weights as those resulting from protease activity released from PMN cells, and as observed in UV-irradiated human skin. Cleavage of decorin by neutrophil elastase significantly augmented fragmentation of type I collagen fibrils by MMP-1. Taken together, these data indicate that PMN cell proteases, especially neutrophil elastase, degrade decorin, and this degradation renders collagen fibrils more susceptible to MMP-1 cleavage. These data identify decorin degradation and neutrophil elastase as potential therapeutic targets for mitigating sun exposure-induced collagen fibril degradation in human skin.

  11. [Clinical examination of children with tooth aplasia. Correlations between dental symptoms and the whole organism].

    PubMed

    Knolmayer, Judit; Bognár, Veronika; Szabó, Gyula

    2008-10-01

    The characteristic abnormalities of jaws, teeth, and salivation can be measured and expressed by numbers. The possible etiological factors, like the positive family history of noxas during the pregnancy can be explored. In our study we examined the symptoms of general organic system and teeth trait--jaw relation, seriousness of aplasia, abnormalities of teeth in size--defect of salivary glands and the presence of possible etiological factors. Thirty children were examined. The symptoms of general organic system were diagnosed. 60% of tooth agenesis occurs in the maxilla, the size of teeth reduced also in the upper jaw. Pseudoprogenia can be explained by these facts. The size reduction of extant teeth appeared stronger in the labiolingual direction. The salivary secretion rate in examined children proved significantly lower than in the control group. Seven siblings and eight parents were identified by examining the etiological factors. We did not find any noxas during the pregnancy by our questionnaire method.

  12. A Novel Mechanism of γ-Irradiation-Induced IL-6 Production Mediated by P2Y11 Receptor in Epidermal Keratinocytes.

    PubMed

    Ohsaki, Airi; Miyano, Yuki; Tanaka, Rei; Tanuma, Sei-Ichi; Kojima, Shuji; Tsukimoto, Mitsutoshi

    2018-06-01

    Skin inflammation is caused by excessive production of cytokines and chemokines in response to an external stimulus, such as radiation, but the mechanisms involved are not completely understood. Here, we report a novel mechanism of γ-irradiation-induced interleukin-6 (IL-6) production mediated by P2Y11 receptors in epidermal cells. After irradiation of HaCaT cells derived from human epidermal keratinocytes with 5 Gy of γ-rays ( 137 Cs: 0.78 Gy/min), IL-6 production was unchanged at 24 h after γ-irradiation, but was increased at 48 h. IL-6 mRNA was increased at 30 h, and IL-6 production was increased at 33 h after irradiation. The production of IL-6 was sustained at least for 4 d after irradiation. P2Y11 receptor antagonist NF157 inhibited IL-6 production in irradiated cells. Treatment with ATP, a ligand of P2Y11 receptor caused IL-6 production within 24 h. ATP-induced IL-6 production was also suppressed by NF157. Extracellular ATP level was increased after irradiation. The p38 mitogen-activated protein kinase (MAPK) and nuclear factor-kappaB (NF-κB) signaling was involved in the production of IL-6 at the downstream of P2Y11 receptor activation. In addition, the cell cycle was arrested at the G2/M phase, and DNA repair foci were not disappeared at 48 h after γ-irradiation. The protein level of histone methylation enzyme G9a, which inhibits IL-6 production, was decreased after γ-irradiation. In conclusion, we suggest that γ-irradiation induces sustained IL-6 production in HaCaT cells from 33 h after irradiation, which is mediated through P2Y11 receptor-p38 MAPK-NF-κB signaling pathway and G9a degradation. This is a novel mechanism of cytokine production in γ-irradiated cells.

  13. Proton-irradiation induced defects in modified 310S steels characterized with positron annihilation spectroscopy and transmission electron microscopy

    NASA Astrophysics Data System (ADS)

    Zhang, Weiping; Shen, Zhenyu; Tang, Rui; Jin, Suoxue; Song, Yaoxiang; Long, Yunxiang; Wei, Yaxia; Zhou, Xiong; Chen, Cheng; Guo, Liping

    2018-07-01

    An effective method to improve the irradiation resistance of austenitic stainless steels is adding oversized solutes into steels. In this work, the irradiation resistances of two type of modified 310S steels, in one of which Zr was added and in another Nb, Ta, and W were added, were investigated by proton irradiations at 563 K. Irradiation induced vacancy-type defects was characterized with positron annihilation spectroscopy (PAS), while dislocation loops and bubbles whose size are greater than 1 nm are characterized with transmission electron microscopy (TEM). It is found that the relative S parameter ΔS/S extracted from PAS is more effective than S parameter in evaluating the quantity of vacancy-type defects. It was revealed from ΔS/S that more vacancy-type defects produced in (Nb, Ta, W)-added steels than that in Zr-added steels, and this trend became more obvious with the dose increasing. S-W curves reveal that proton irradiation induced two kinds of vacancy-type defects, i.e. vacancy clusters and proton-vacancy clusters. TEM observation shows that the density of small bubbles induced by proton in (Nb, Ta, W)-added steels is much higher than that in Zr-added steels. Both 1/3 <1 1 1> and 1/2 <1 1 0> dislocation loops were observed with TEM in all of the specimens. The mean size and number density of dislocation loops in (Nb, Ta, W)-added steels are slightly larger than that in Zr-added steels, and increased with increasing irradiation dose. Both PAS and TEM observations shows that irradiation damage in Zr-added steels is less serious than that (Nb, Ta, W)-added steels, and the possible mechanisms are discussed through the enhancement of point defect recombination by oversized solute atoms.

  14. Laser-induced reduction of graphene oxide powders by high pulsed ultraviolet laser irradiations

    NASA Astrophysics Data System (ADS)

    Yang, Chii-Rong; Tseng, Shih-Feng; Chen, Yu-Ting

    2018-06-01

    This study aims to develop a laser-induced reduction approach for graphene oxide (GO) powders fabricated by using high pulsed ultraviolet laser irradiations. Before and after the laser irradiation with different fluences, the physical and electrical properties of homemade GO powders and reduced graphene oxide (rGO) powders were measured and analyzed using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), surface area analyzer, and four-point probe instrument. The laser irradiation parameters included the pulse repetition frequency of 100 kHz, the scanning speed of galvanometers of 50 mm/s, the number of laser irradiated cycles of 10, and the laser fluences of ranging from 0.153 mJ/cm2 to 0.525 mJ/cm2. The laser reduction experiments of GO powders demonstrated that the largest relative intensity of the 2D peak and specific surface area were found at the laser fluence of 0.438 mJ/cm2. Moreover, the electrical resistance sharply decreased from 280 MΩ in the initial GO powders to 0.267 MΩ in rGO powders at a laser irradiation fluence of 0.438. The C/O ratio was increased from 0.232 in the initial GO powders to 1.86 in the rGO powders at a laser irradiation fluence of 0.525 mJ/cm2; furthermore, the C/O ratios increased with increasing the laser fluences.

  15. Irradiation hardening of pure tungsten exposed to neutron irradiation

    DOE PAGES

    Hu, Xunxiang; Koyanagi, Takaaki; Fukuda, Makoto; ...

    2016-08-26

    In this paper, pure tungsten samples have been neutron irradiated in HFIR at 90–850 °C to 0.03–2.2 dpa. A dispersed barrier hardening model informed by the available microstructure data has been used to predict the hardness. Comparison of the model predictions and the measured Vickers hardness reveals the dominant hardening contribution at various irradiation conditions. For tungsten samples irradiated in HFIR, the results indicate that voids and dislocation loops contributed to the hardness increase in the low dose region (<0.3 dpa), while the formation of intermetallic second phase precipitation, resulting from transmutation, dominates the radiation-induced strengthening beginning with a relativelymore » modest dose (>0.6 dpa). Finally, the precipitate contribution is most pronounced for the HFIR irradiations, whereas the radiation-induced defect cluster microstructure can rationalize the entirety of the hardness increase observed in tungsten irradiated in the fast neutron spectrum of Joyo and the mixed neutron spectrum of JMTR.« less

  16. Ion irradiation induced surface modification studies of polymers using SPM

    NASA Astrophysics Data System (ADS)

    Tripathi, A.; Kumar, Amit; Singh, F.; Kabiraj, D.; Avasthi, D. K.; Pivin, J. C.

    2005-07-01

    Various types of scanning probe microscopy (SPM) techniques: atomic force microscopy (AFM) (contact and tapping in height and amplitude mode), scanning tunnelling microscopy (STM) and conducting atomic force microscopy (C-AFM) are used for studying ion beam induced surface modifications, nanostructure/cluster formation and disintegration in polymers and similar soft carbon based materials. In the present study, the results of studies on four materials, namely, (A) methyltriethoxysilane/phenyltriethoxysilane (MTES/PTES) based gel, (B) triethoxisilane (TH) based gel, (C) highly oriented pyrolytic graphite (HOPG) bulk and (D) fullerene (C60) thin films are discussed. In the case of Si based gels prepared from pre-cursors containing organic groups (MTES/PTES), hillocks are observed at the surface and their size decreases from 70 to 25 nm with increasing fluence, whereas, in the case of a gel with a stoichiometry SiO1.25H1, prepared from TH, an increases in the size of hillocks is observed. Hillocks are also formed at the surface of HOPG irradiated with 120 MeV Au beam at a low fluence, whereas, formation of craters and a re-organisation of surface features is observed at a higher fluence. In the case of C60 films, 120 MeV Au ion irradiation induces the formation of conducting ion tracks, which is attributed to the transformation from insulating C60 to conducting graphite like carbon.

  17. Night work, long work weeks, and risk of accidental injuries. A register-based study.

    PubMed

    Larsen, Ann D; Hannerz, Harald; Møller, Simone V; Dyreborg, Johnny; Bonde, Jens Peter; Hansen, Johnni; Kolstad, Henrik A; Hansen, Åse Marie; Garde, Anne Helene

    2017-11-01

    Objectives The aims of this study were to (i) investigate the association between night work or long work weeks and the risk of accidental injuries and (ii) test if the association is affected by age, sex or socioeconomic status. Methods The study population was drawn from the Danish version of the European Labour Force Survey from 1999-2013. The current study was based on 150 438 participants (53% men and 47% women). Data on accidental injuries were obtained at individual level from national health registers. We included all 20-59-year-old employees working ≥32 hours a week at the time of the interview. We used Poisson regression to estimate the relative rates (RR) of accidental injuries as a function of night work or long work weeks (>40 hours per week) adjusted for year of interview, sex, age, socioeconomic status (SES), industry, and weekly working hours or night work. Age, sex and SES were included as two-way interactions. Results We observed 23 495 cases of accidental injuries based on 273 700 person years at risk. Exposure to night work was statistically significantly associated with accidental injuries (RR 1.11, 99% CI 1.06-1.17) compared to participants with no recent night work. No associations were found between long work weeks (>40 hours) and accidental injuries. Conclusion We found a modest increased risk of accidental injuries when reporting night work. No associations between long work weeks and risk of accidental injuries were observed. Age, sex and SES showed no trends when included as two-way interactions.

  18. Spatially-Selective Membrane Permeabilization Induced by Cell-Solution Electrode Atmospheric Pressure Plasma Irradiation

    NASA Astrophysics Data System (ADS)

    Sasaki, Shota; Hokari, Yutaro; Kanzaki, Makoto; Kaneko, Toshiro

    2015-09-01

    Gene transfection, which is the process of deliberately introducing nucleic acids into cells, is expected to play an important role in medical treatment because the process is necessary for gene therapy and creation of induced pluripotent stem (iPS) cells. However, the conventional transfection methods have some problems, so we focus attention on promising transfection methods by atmospheric pressure plasma (APP). We have previously reported that the cell membrane permeability, which is closely related with gene transfection, is improved using a cell-solution electrode for generating He-APP. He-APP is irradiated to the solution containing the adherent cells and delivery materials such as fluorescent dyes (YOYO-1) and plasmid DNA (GFP). In case of YOYO-1 delivery, more than 80% of cells can be transferred only in the plasma-irradiated area and the spatially-selective membrane permeabilization is realized by the plasma irradiation. In addition, it is confirmed that plasmid DNA is transfected and the GFP genes are expressed using same APP irradiation system with no obvious cellular damage.

  19. Positive and negative tropic curvature induced by microbeam irradiation of protonemal tip cells of the moss Ceratodon purpureus.

    PubMed

    Lamparter, T; Kagawa, T; Brücker, G; Wada, M

    2004-01-01

    The photoreceptor phytochrome mediates tropic responses in protonemata of the moss Ceratodon purpureus. Under standard conditions the tip cells grow towards unilateral red light, or perpendicular to the electrical vector of polarized light. In this study the response of tip cells to partial irradiation of the apical region was analysed using a microbeam apparatus. The fluence response curve gave an unexpected pattern: whereas a 15-min microbeam with light intensities around 3 micro mol m (-2) s (-1) induced a growth curvature towards the irradiated side, higher light intensities around 100 micro mol m (-2) s (-1) caused a negative response, the cells grew away from the irradiated side. This avoidance response is explained by two effects: the light intensity is high enough to induce photoconversion into the active Pfr form of phytochrome, not only on the irradiated but also on the non-irradiated side by stray light. At the same time, the strong light on the irradiated side acts antagonistically to Pfr. As a result of this inhibition, the growth direction is moved to the light-avoiding side. Such a Pfr-independent mechanism might be important for the phototropic response to distinguish between the light-directed and light-avoiding side under unilateral light.

  20. Radiation induced segregation and precipitation behavior in self-ion irradiated Ferritic/Martensitic HT9 steel

    DOE PAGES

    Zheng, Ce; Auger, Maria A.; Moody, Michael P.; ...

    2017-04-24

    In this study, Ferritic/Martensitic (F/M) HT9 steel was irradiated to 20 displacements per atom (dpa) at 600 nm depth at 420 and 440 °C, and to 1, 10 and 20 dpa at 600 nm depth at 470 °C using 5 MeV Fe++ ions. The characterization was conducted using ChemiSTEM and Atom Probe Tomography (APT), with a focus on radiation induced segregation and precipitation. Ni and/or Si segregation at defect sinks (grain boundaries, dislocation lines, carbide/matrix interfaces) together with Ni, Si, Mn rich G-phase precipitation were observed in self-ion irradiated HT9 except in very low dose case (1 dpa at 470more » °C). Some G-phase precipitates were found to nucleate heterogeneously at defect sinks where Ni and/or Si segregated. In contrast to what was previously reported in the literature for neutron irradiated HT9, no Cr-rich α' phase, χ-phases, η phase and voids were found in self-ion irradiated HT9. The difference of observed microstructures is probably due to the difference of irradiation dose rate between ion irradiation and neutron irradiation. In addition, the average size and number density of G-phase precipitates were found to be sensitive to both irradiation temperature and dose. With the same irradiation dose, the average size of G-phase increased whereas the number density decreased with increasing irradiation temperature. Within the same irradiation temperature, the average size increased with increasing irradiation dose.« less

  1. The big chill: accidental hypothermia.

    PubMed

    Davis, Robert Allan

    2012-01-01

    A potential cause of such emergent issues as cardiac arrhythmias, hypotension, and fluid and electrolyte shifts, accidental hypothermia can be deadly, is common among trauma patients, and is often difficult to recognize. The author discusses predisposing conditions, the classic presentation, and the effects on normal thermoregulatory processes; explains how to conduct a systems assessment of the hypothermic patient; and describes crucial management strategies.

  2. Tranexamic acid suppresses ultraviolet B eye irradiation-induced melanocyte activation by decreasing the levels of prohormone convertase 2 and alpha-melanocyte-stimulating hormone.

    PubMed

    Hiramoto, Keiichi; Yamate, Yurika; Sugiyama, Daijiro; Takahashi, Yumi; Mafune, Eiichi

    2014-12-01

    Tranexamic acid (trans-4-aminomethylcyclohexanecarboxylic acid) is a medicinal amino acid used in skin whitening care. This study examined the effects of tranexamic acid on the melanocyte activation of the skin induced by an ultraviolet (UV) B eye irradiation. The eye or ear was locally exposed to UVB at a dose of 1.0 kJ/m(2) using a 20SE sunlamp after covering the remaining body surface with aluminum foil. UVB eye irradiation induced melanocyte activation of the skin, similar to that observed following UVB ear irradiation, which was suppressed by the administration of tranexamic acid treatment. The plasma α-melanocyte-stimulating hormone (α-MSH) content was increased by UVB irradiation of the eye; however, the increase in α-MSH was suppressed by tranexamic acid treatment. In addition, UVB eye irradiation induced the up-regulation of prohormone convertase (PC) 2 in the pituitary gland. Meanwhile, the increase in PC2 induced by UVB eye irradiation was suppressed by tranexamic acid treatment. These results clearly indicate that tranexamic acid decreases the expression of PC2, which cleavages from proopiomelanocortin to α-MSH in the pituitary gland, thereby suppressing melanocyte activation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Mitoquinone restores platelet production in irradiation-induced thrombocytopenia

    PubMed Central

    Ramsey, Haley; Zhang, Qi; Wu, Mei X.

    2014-01-01

    Myelodysplastic syndromes (MDS) are hallmarked by cytopenia and dysplasia of hematopoietic cells, often accompanied by mitochondrial dysfunction and increases of reactive oxygen species (ROS) within affected cells. However, it is not known whether the increase in ROS production is an instigator or a byproduct of the disease. The present investigation shows that mice lacking immediate early responsive gene X-1 (IEX-1) exhibit lineage specific increases in ROS production and abnormal cytology upon radiation in blood cell types commonly identified in MDS. These affected cell lineages chiefly have the bone marrow as a primary site of differentiation and maturation, while cells with extramedullary differentiation and maturation like B- and T-cells remain unaffected. Increased ROS production is likely to contribute significantly to irradiation-induced thrombocytopenia in the absence of IEX-1 as demonstrated by effective reversal of the disorder after mitoquinone (MitoQ) treatment, a mitochondria-specific antioxidant. MitoQ reduced intracellular ROS production within megakaryocytes and platelets. It also normalized mitochondrial membrane potential and superoxide production in platelets in irradiated, IEX-1 deficient mice. The lineage-specific effects of mitochondrial ROS may help us understand the etiology of thrombocytopenia in association with MDS in a subgroup of the patients. PMID:25025394

  4. Accidental Falls Among Geriatric Patients: Can More Be Prevented?

    PubMed Central

    Johnson, Edwin T.

    1985-01-01

    The potential for accidental falls among geriatric patients is of mounting concern. Two hundred forty-one accidental falls over a 12-month period at the VA Medical Center were analyzed retrospectively and the literature reviewed in order to highlight factors that have bearing on the incidence and severity of falls. If a patient's potential for falling could be identified through a grading system based on these premonitory features, preventive measures might be more clearly focused where needed to reduce this frequent hazard in our hospital population. PMID:4046062

  5. On the 16O 6+ ion irradiation induced magnetic moment generation in ZnFe2O4 nano ferrite

    NASA Astrophysics Data System (ADS)

    Satalkar, M.; Kane, S. N.; Raghuvanshi, S.

    2018-05-01

    X-ray diffraction (XRD) was utilized to study the effect of 80 MeV 16O 6+ ion irradiation of the as-burnt ZnFe2O4 samples, prepared by sol-gel auto-combustion technique. The samples were irradiated at fluence: 1 × 1011, 1 × 1012, 1 × 1013, 1 × 1014 ions/cm2 to observe the effect of irradiation on structural properties and cationic distribution. XRD confirms the formation of single phase nanocrystalline cubic spinel ferrites with Scherrer's particle diameter (D) ranging between 15.7 - 17.4 nm. Results very distinctly show the electronic energy loss induced changes in: - experimental and theoretical lattice parameter (aexp., ath.), tetrahedral and octahedral bond length (RA, RB), and shared tetrahedral and octahedral edge (dAE, dBE). The paper reports the generation of magnetic moment of Zn ferrite by swift heavy ion irradiation induced distortion at tetrahedral site.

  6. Epidemiology of Munchausen syndrome by proxy, non-accidental poisoning, and non-accidental suffocation.

    PubMed Central

    McClure, R J; Davis, P M; Meadow, S R; Sibert, J R

    1996-01-01

    A two year prospective study was performed to determine the epidemiology of Munchausen syndrome by proxy, non-accidental poisoning, and non-accidental suffocation in the UK and the Republic of Ireland. Cases were notified to the British Paediatric Association Surveillance Unit from September 1992 to August 1994 if a formal case conference had been held for the first time during that period to discuss any of the above conditions. A total of 128 cases were identified: 55 suffered Munchausen syndrome by proxy alone, 15 poisoning, and 15 suffocation; 43 suffered more than one type of abuse. The majority of children were aged under 5 years, the median age being 20 months. On 85% of occasions the perpetrator was the child's mother. In 42% of families with more than one child, a sibling had previously suffered some form of abuse. Eighty five per cent of notifying paediatricians considered the probability of their diagnosis as virtually certain before a case conference was convened. The commonest drugs used to poison were anticonvulsants; opiates were the second commonest. Sixty eight children suffered severe illness of whom eight died. The combined annual incidence of these conditions in children aged under 16 years is at least 0.5/100,000, and for children aged under 1, at least 2.8/100,000. PMID:8813872

  7. Chlorophyll degradation in aqueous mediums induced by light and UV-B irradiation: An UHPLC-ESI-MS study

    NASA Astrophysics Data System (ADS)

    Petrović, Sanja; Zvezdanović, Jelena; Marković, Dejan

    2017-12-01

    Irreversible chlorophyll degradation induced by continuous white light illumination and UV-B irradiation in the aqueous mediums (with 10%, 30% and 50% of methanol) was investigated using the ultrahigh liquid chromatography coupled with diode array and electrospray ionization mass spectrometry detectors (UHPLC-DAD-ESIMS). The degradation was governed by energy input of photons: higher energy of UV-B irradiation induced faster chlorophyll degradation and accordingly faster products formation in comparison to the white light treatment. Main light- or/and UV-B-induced products of chlorophyll in the aqueous mediums were hydroxy-pheophytin a, pheophytin a and hydroxy-lactone-pheophytin a, accompanied with the corresponding epimers. Chlorophylls aggregation dominant in the aqueous medium with the highest methanol content (50%) play a protective role against the UV-B radiation and white light illumination.

  8. Analysis of Heavy Ion Irradiation Induced Thermal Damage in SiC Schottky Diodes

    NASA Astrophysics Data System (ADS)

    Abbate, C.; Busatto, G.; Cova, P.; Delmonte, N.; Giuliani, F.; Iannuzzo, F.; Sanseverino, A.; Velardi, F.

    2015-02-01

    A study is presented aimed at describing phenomena involved in Single Event Burnout induced by heavy ion irradiation in SiC Schottky diodes. On the basis of experimental data obtained for 79Br irradiation at different energies, electro-thermal FEM is used to demonstrate that the failure is caused by a strong local increase of the semiconductor temperature. With respect to previous studies the temperature dependent thermal material properties were added. The critical ion energy calculated by this model is in agreement with literature experimental results. The substrate doping dependence of the SEE robustness was analyzed, proving the effectiveness of the developed model for device technological improvements.

  9. Effects of accidental hypothermia on posttraumatic complications and outcome in multiple trauma patients.

    PubMed

    Mommsen, P; Andruszkow, H; Frömke, C; Zeckey, C; Wagner, U; van Griensven, M; Frink, M; Krettek, C; Hildebrand, F

    2013-01-01

    Accidental hypothermia seems to predispose multiple trauma patients to the development of posttraumatic complications, such as Systemic Inflammatory Response Syndrome (SIRS), sepsis, Multiple Organ Dysfunction Syndrome (MODS), and increased mortality. However, the role of accidental hypothermia as an independent prognostic factor is controversially discussed. The aim of the present study was to evaluate the incidence of accidental hypothermia in multiple trauma patients and its effects on the development of posttraumatic complications and mortality. Inclusion criteria for patients in this retrospective study (2005-2009) were an Injury Severity Score (ISS) ≥16, age ≥16 years, admission to our Level I trauma centre within 6h after the accident. Accidental hypothermia was defined as body temperature less than 35°C measured within 2 h after admission, but always before first surgical procedure in the operation theatre. The association between accidental hypothermia and the development of posttraumatic complications as well as mortality was investigated. Statistical analysis was performed with χ(2)-test, Student's t-test, ANOVA and logistic regression. Statistical significance was considered at p<0.05. 310 multiple trauma patients were enrolled in the present study. Patients' mean age was 41.9 (SD 17.5) years, the mean injury severity score was 29.7 (SD 10.2). The overall incidence of accidental hypothermia was 36.8%. The overall incidence of posttraumatic complications was 77.4% (SIRS), 42.9% (sepsis) and 7.4% (MODS), respectively. No association was shown between accidental hypothermia and the development of posttraumatic complications. Overall, 8.7% died during the posttraumatic course. Despite an increased mortality rate in hypothermic patients, hypothermia failed to be an independent risk factor for mortality in multivariate analysis. Accidental hypothermia is very common in multiply injured patients. However, it could be assumed that the increase of

  10. Dental pain as a risk factor for accidental acetaminophen overdose: a case-control study.

    PubMed

    Vogel, Jody; Heard, Kennon J; Carlson, Catherine; Lange, Chad; Mitchell, Garrett

    2011-11-01

    Patients frequent take acetaminophen to treat dental pain. One previous study found a high rate of overuse of nonprescription analgesics in an emergency dental clinic. The purpose of this study is to determine if patients with dental pain are more likely to be treated for accidental acetaminophen poisoning than patients with other types of pain. We conducted a case-control study at 2 urban hospitals. Cases were identified by chart review of patients who required treatment for accidental acetaminophen poisoning. Controls were self-reported acetaminophen users taking therapeutic doses identified during a survey of emergency department patients. For our primary analysis, the reason for taking acetaminophen was categorized as dental pain or not dental pain. Our primary outcome was the odds ratio of accidental overdose to therapeutic users after adjustment for age, sex, alcoholism, and use of combination products using logistic regression. We identified 73 cases of accidental acetaminophen poisoning and 201 therapeutic users. Fourteen accidental overdose patients and 4 therapeutic users reported using acetaminophen for dental pain. The adjusted odds ratio for accidental overdose due to dental pain compared with other reasons for use was 12.8 (95% confidence interval, 4.2-47.6). We found that patients with dental pain are at increased risk to accidentally overdose on acetaminophen compared with patients taking acetaminophen for other reasons. Emergency physicians should carefully question patients with dental pain about overuse of analgesics. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Electron irradiation induced effects on the physico-chemical properties of L-Arginine Maleate Dihydrate (LAMD) single crystals

    NASA Astrophysics Data System (ADS)

    Thomas, Prince; Dhole, S. D.; Joseph, Ginson P.

    2018-07-01

    Single crystals of L-Arginine Maleate Dihydrate (LAMD) have been synthesized by slow solvent evaporation technique and irradiated with 6 MeV electrons at fluences of 0.5 ×1015e /cm2 , 1.0 ×1015e /cm2 and 1.5 ×1015e /cm2 . The Powder X-ray Diffraction (PXRD) studies showed that the intensity of the diffraction peaks of the Electron Beam (EB) irradiated crystals decreases with irradiation fluence. The electron irradiation induced effects on the optical parameters such as cut-off wavelength, band gap, Urbach energy and refractive index have been studied and the results are tabulated. The electronic parameters such as valence electron plasma energy, ℏωp , Penn gap, Ep , Fermi energy, EF and Electronic polarizability, α for pure and irradiated LAMD crystals are calculated. The electrical and thermal properties of the pure and irradiated LAMD crystals are also investigated.

  12. HRTEM and chemical study of an ion-irradiated chromium/zircaloy-4 interface

    NASA Astrophysics Data System (ADS)

    Wu, A.; Ribis, J.; Brachet, J.-C.; Clouet, E.; Leprêtre, F.; Bordas, E.; Arnal, B.

    2018-06-01

    Chromium-coated zirconium alloys are being studied as Enhanced Accident Tolerant Fuel Cladding for Light Water Reactors (LWRs). Those materials are especially studied to improve the oxidation resistance of LWRs current fuel claddings in nominal and at High Temperature (HT) for hypothetical accidental conditions such as LOss of Coolant Accident. Beyond their HT behavior, it is essential to assess the materials behavior under irradiation. A first generation chromium/Zircaloy-4 interface was thus irradiated with 20 MeV Kr8+ ions at 400 °C up to 10 dpa. High-Resolution Transmission Electron Microscopy and chemical analysis (EDS) were conducted at the Cr/Zr interface. The atomic structure of the interface reveals the presence of Zr(Fe, Cr)2 Laves phase, displaying both C14 and C15 structure. After irradiation, only the C14 structure was observed and atomic row matching was preserved across the different interfaces, thus ensuring a good adhesion of the coating after irradiation.

  13. Thermal stability of deep level defects induced by high energy proton irradiation in n-type GaN

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Farzana, E.; Sun, W. Y.; Chen, J.; Zhang, E. X.; Fleetwood, D. M.; Schrimpf, R. D.; McSkimming, B.; Kyle, E. C. H.; Speck, J. S.; Arehart, A. R.; Ringel, S. A.

    2015-10-01

    The impact of annealing of proton irradiation-induced defects in n-type GaN devices has been systematically investigated using deep level transient and optical spectroscopies. Moderate temperature annealing (>200-250 °C) causes significant reduction in the concentration of nearly all irradiation-induced traps. While the decreased concentration of previously identified N and Ga vacancy related levels at EC - 0.13 eV, 0.16 eV, and 2.50 eV generally followed a first-order reaction model with activation energies matching theoretical values for NI and VGa diffusion, irradiation-induced traps at EC - 0.72 eV, 1.25 eV, and 3.28 eV all decrease in concentration in a gradual manner, suggesting a more complex reduction mechanism. Slight increases in concentration are observed for the N-vacancy related levels at EC - 0.20 eV and 0.25 eV, which may be due to the reconfiguration of other N-vacancy related defects. Finally, the observed reduction in concentrations of the states at EC - 1.25 and EC - 3.28 eV as a function of annealing temperature closely tracks the detailed recovery behavior of the background carrier concentration as a function of annealing temperature. As a result, it is suggested that these two levels are likely to be responsible for the underlying carrier compensation effect that causes the observation of carrier removal in proton-irradiated n-GaN.

  14. Effect of gamma-ray irradiation on the device process-induced defects in 4H-SiC epilayers

    NASA Astrophysics Data System (ADS)

    Miyazaki, T.; Makino, T.; Takeyama, A.; Onoda, S.; Ohshima, T.; Tanaka, Y.; Kandori, M.; Yoshie, T.; Hijikata, Y.

    2016-11-01

    We investigated the gamma-ray irradiation effect on 4H-SiC device process-induced defects by photoluminescence (PL) imaging and deep level transient spectroscopy (DLTS). We found that basal plane dislocations (BPDs) that were present before the irradiation were eliminated by gamma-ray irradiation of 1 MGy. The reduction mechanism of BPD was discussed in terms of BPD-threading edge dislocation (TED) transformation and shrinkage of stacking faults. In addition, the entire PL image was gradually darkened with increasing absorbed dose, which is presumably due to the point defects generated by gamma-ray irradiation. We obtained DLTS peaks that could be assigned to complex defects, termed RD series, and found that the peaks increased with absorbed dose.

  15. Irradiation-induced precipitation and mechanical properties of vanadium alloys at <430 C

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chung, H.M.; Gazda, J.; Smith, D.L.

    Recent attention to V-base alloys has focused on the effect of low-temperature (<430 C) irradiation on tensile and impact properties of V-4Cr-4Ti. In previous studies, dislocation channeling, which causes flow localization and severe loss of work-hardening capability, has been attributed to dense, irradiation-induced precipitation of very fine particles. However, efforts to identify the precipitates were unsuccessful until now. In this study, analysis by transmission electron microscopy (TEM) was conducted on unalloyed V, V-5Ti, V-3Ti-1Si, and V-4Cr-4Ti specimens that were irradiated at <430 C in conventional and dynamic helium charging experiments. By means of dark-field imaging and selected-area-diffraction analysis, the characteristicmore » precipitates were identified to be (V,Ti{sub 1{minus}x})(C,O,N). In V-3Ti-1Si, precipitation of (V,Ti{sub 1{minus}x})(C,O,N) was negligible at <430 C, and as a result, dislocation channeling did not occur and work-hardening capability was high.« less

  16. Recrystallization-Induced Surface Cracks of Carbon Ions Irradiated 6H-SiC after Annealing

    PubMed Central

    Ye, Chao; Ran, Guang; Zhou, Wei; Shen, Qiang; Feng, Qijie; Lin, Jianxin

    2017-01-01

    Single crystal 6H-SiC wafers with 4° off-axis [0001] orientation were irradiated with carbon ions and then annealed at 900 °C for different time periods. The microstructure and surface morphology of these samples were investigated by grazing incidence X-ray diffraction (GIXRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Ion irradiation induced SiC amorphization, but the surface was smooth and did not have special structures. During the annealing process, the amorphous SiC was recrystallized to form columnar crystals that had a large amount of twin structures. The longer the annealing time was, the greater the amount of recrystallized SiC would be. The recrystallization volume fraction was accorded with the law of the Johnson–Mehl–Avrami equation. The surface morphology consisted of tiny pieces with an average width of approximately 30 nm in the annealed SiC. The volume shrinkage of irradiated SiC layer and the anisotropy of newly born crystals during annealing process produced internal stress and then induced not only a large number of dislocation walls in the non-irradiated layer but also the initiation and propagation of the cracks. The direction of dislocation walls was perpendicular to the growth direction of the columnar crystal. The longer the annealing time was, the larger the length and width of the formed crack would be. A quantitative model of the crack growth was provided to calculate the length and width of the cracks at a given annealing time. PMID:29068408

  17. Recrystallization-Induced Surface Cracks of Carbon Ions Irradiated 6H-SiC after Annealing.

    PubMed

    Ye, Chao; Ran, Guang; Zhou, Wei; Shen, Qiang; Feng, Qijie; Lin, Jianxin

    2017-10-25

    Single crystal 6H-SiC wafers with 4° off-axis [0001] orientation were irradiated with carbon ions and then annealed at 900 °C for different time periods. The microstructure and surface morphology of these samples were investigated by grazing incidence X-ray diffraction (GIXRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Ion irradiation induced SiC amorphization, but the surface was smooth and did not have special structures. During the annealing process, the amorphous SiC was recrystallized to form columnar crystals that had a large amount of twin structures. The longer the annealing time was, the greater the amount of recrystallized SiC would be. The recrystallization volume fraction was accorded with the law of the Johnson-Mehl-Avrami equation. The surface morphology consisted of tiny pieces with an average width of approximately 30 nm in the annealed SiC. The volume shrinkage of irradiated SiC layer and the anisotropy of newly born crystals during annealing process produced internal stress and then induced not only a large number of dislocation walls in the non-irradiated layer but also the initiation and propagation of the cracks. The direction of dislocation walls was perpendicular to the growth direction of the columnar crystal. The longer the annealing time was, the larger the length and width of the formed crack would be. A quantitative model of the crack growth was provided to calculate the length and width of the cracks at a given annealing time.

  18. Anti-tumor response induced by immunologically modified carbon nanotubes and laser irradiation using rat mammary tumor model

    NASA Astrophysics Data System (ADS)

    Acquaviva, Joseph T.; Hasanjee, Aamr M.; Bahavar, Cody F.; Zhou, Fefian; Liu, Hong; Howard, Eric W.; Bullen, Liz C.; Silvy, Ricardo P.; Chen, Wei R.

    2015-03-01

    Laser immunotherapy (LIT) is being developed as a treatment modality for metastatic cancer which can destroy primary tumors and induce effective systemic anti-tumor responses by using a targeted treatment approach in conjunction with the use of a novel immunoadjuvant, glycated chitosan (GC). In this study, Non-invasive Laser Immunotherapy (NLIT) was used as the primary treatment mode. We incorporated single-walled carbon nanotubes (SWNTs) into the treatment regimen to boost the tumor-killing effect of LIT. SWNTs and GC were conjugated to create a completely novel, immunologically modified carbon nanotube (SWNT-GC). To determine the efficacy of different laser irradiation durations, 5 minutes or 10 minutes, a series of experiments were performed. Rats were inoculated with DMBA-4 cancer cells, a highly aggressive metastatic cancer cell line. Half of the treatment group of rats receiving laser irradiation for 10 minutes survived without primary or metastatic tumors. The treatment group of rats receiving laser irradiation for 5 minutes had no survivors. Thus, Laser+SWNT-GC treatment with 10 minutes of laser irradiation proved to be effective at reducing tumor size and inducing long-term anti-tumor immunity.

  19. High temperature irradiation induced creep in Ag nanopillars measured via in situ transmission electron microscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jawaharram, Gowtham Sriram; Price, Patrick M.; Barr, Christopher M.

    Irradiation induced creep (IIC) rates are measured in compression on Ag nanopillar (square) beams in the sink-limited regime. The IIC rate increases linearly with stress at lower stresses, i.e. below ≈2/3 the high temperature yield stress and parabolically with pillar width, L, for L less than ≈300 nm. Here, the data are obtained by combining in situ transmission electron imaging with simultaneous ion irradiation, laser heating, and nanopillar compression. Results in the larger width regime are consistent with prior literature.

  20. High temperature irradiation induced creep in Ag nanopillars measured via in situ transmission electron microscopy

    DOE PAGES

    Jawaharram, Gowtham Sriram; Price, Patrick M.; Barr, Christopher M.; ...

    2018-01-30

    Irradiation induced creep (IIC) rates are measured in compression on Ag nanopillar (square) beams in the sink-limited regime. The IIC rate increases linearly with stress at lower stresses, i.e. below ≈2/3 the high temperature yield stress and parabolically with pillar width, L, for L less than ≈300 nm. Here, the data are obtained by combining in situ transmission electron imaging with simultaneous ion irradiation, laser heating, and nanopillar compression. Results in the larger width regime are consistent with prior literature.

  1. Reversible Hydrophobic to Hydrophilic Transition in Graphene via Water Splitting Induced by UV Irradiation

    PubMed Central

    Xu, Zhemi; Ao, Zhimin; Chu, Dewei; Younis, Adnan; Li, Chang Ming; Li, Sean

    2014-01-01

    Although the reversible wettability transition between hydrophobic and hydrophilic graphene under ultraviolet (UV) irradiation has been observed, the mechanism for this phenomenon remains unclear. In this work, experimental and theoretical investigations demonstrate that the H2O molecules are split into hydrogen and hydroxyl radicals, which are then captured by the graphene surface through chemical binding in an ambient environment under UV irradiation. The dissociative adsorption of H2O molecules induces the wettability transition in graphene from hydrophobic to hydrophilic. Our discovery may hold promise for the potential application of graphene in water splitting. PMID:25245110

  2. Comprehensive identification of mutations induced by heavy-ion beam irradiation in Arabidopsis thaliana.

    PubMed

    Hirano, Tomonari; Kazama, Yusuke; Ishii, Kotaro; Ohbu, Sumie; Shirakawa, Yuki; Abe, Tomoko

    2015-04-01

    Heavy-ion beams are widely used for mutation breeding and molecular biology. Although the mutagenic effects of heavy-ion beam irradiation have been characterized by sequence analysis of some restricted chromosomal regions or loci, there have been no evaluations at the whole-genome level or of the detailed genomic rearrangements in the mutant genomes. In this study, using array comparative genomic hybridization (array-CGH) and resequencing, we comprehensively characterized the mutations in Arabidopsis thaliana genomes irradiated with Ar or Fe ions. We subsequently used this information to investigate the mutagenic effects of the heavy-ion beams. Array-CGH demonstrated that the average number of deleted areas per genome were 1.9 and 3.7 following Ar-ion and Fe-ion irradiation, respectively, with deletion sizes ranging from 149 to 602,180 bp; 81% of the deletions were accompanied by genomic rearrangements. To provide a further detailed analysis, the genomes of the mutants induced by Ar-ion beam irradiation were resequenced, and total mutations, including base substitutions, duplications, in/dels, inversions, and translocations, were detected using three algorithms. All three resequenced mutants had genomic rearrangements. Of the 22 DNA fragments that contributed to the rearrangements, 19 fragments were responsible for the intrachromosomal rearrangements, and multiple rearrangements were formed in the localized regions of the chromosomes. The interchromosomal rearrangements were detected in the multiply rearranged regions. These results indicate that the heavy-ion beams led to clustered DNA damage in the chromosome, and that they have great potential to induce complicated intrachromosomal rearrangements. Heavy-ion beams will prove useful as unique mutagens for plant breeding and the establishment of mutant lines. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  3. Radiation-induced segregation at grain boundaries in AL-6XN stainless steels irradiated by hydrogen ions

    NASA Astrophysics Data System (ADS)

    Long, Yunxiang; Zheng, Zhongcheng; Guo, Liping; Zhang, Weiping; Shen, Zhenyu; Tang, Rui

    2018-04-01

    The effect of high concentration of hydrogen on the segregation of radiation-induced segregation (RIS) in AL-6XN stainless steels has been investigated by transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy. Specimens were irradiated with 100 keV H2+ ions from 1 dpa to 5 dpa at 380 °C to investigated the dose dependence of grain boundary RIS. A specimen was irradiated to 5 dpa at 290 °C to study the effect of irradiation temperature. The trends of Cr depletion and Ni enrichment with irradiation dose is similar to that of other austenitic steels reported in the literatures, but the higher concentration of hydrogen made the RIS profile wider. An abnormal phenomenon that the degree of RIS increased with decreasing irradiation temperature was found, indicating that with the retention of hydrogen in the steels, temperature dependence of RIS is dominated by the quantity of retained hydrogen, rather than by thermal segregation processes.

  4. AGC-2 Irradiation Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rohrbaugh, David Thomas; Windes, William; Swank, W. David

    The Next Generation Nuclear Plant (NGNP) will be a helium-cooled, very high temperature reactor (VHTR) with a large graphite core. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor (HTGR) designs.[ , ] Nuclear graphite H 451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphites have been developed and are considered suitable candidates for the new NGNP reactor design. To support the design and licensing of NGNP core components within a commercial reactor, a completemore » properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade with a specific emphasis on data related to the life limiting effects of irradiation creep on key physical properties of the NGNP candidate graphites. Based on experience with previous graphite core components, the phenomenon of irradiation induced creep within the graphite has been shown to be critical to the total useful lifetime of graphite components. Irradiation induced creep occurs under the simultaneous application of high temperatures, neutron irradiation, and applied stresses within the graphite components. Significant internal stresses within the graphite components can result from a second phenomenon—irradiation induced dimensional change. In this case, the graphite physically changes i.e., first shrinking and then expanding with increasing neutron dose. This disparity in material volume change can induce significant internal stresses within graphite components. Irradiation induced creep relaxes these large internal stresses, thus reducing the risk of crack formation and component failure. Obviously, higher irradiation creep levels tend to relieve more internal stress, thus allowing the

  5. Involving Parents in Indicated Early Intervention for Childhood PTSD Following Accidental Injury

    ERIC Educational Resources Information Center

    Cobham, Vanessa E.; March, Sonja; De Young, Alexandra; Leeson, Fiona; Nixon, Reginald; McDermott, Brett; Kenardy, Justin

    2012-01-01

    Accidental injuries represent the most common type of traumatic event to which a youth is likely to be exposed. While the majority of youth who experience an accidental injury will recover spontaneously, a significant proportion will go on to develop Post-Traumatic Stress Disorder (PTSD). And yet, there is little published treatment outcome…

  6. Hypofractionated Irradiation Has Immune Stimulatory Potential and Induces a Timely Restricted Infiltration of Immune Cells in Colon Cancer Tumors

    PubMed Central

    Frey, Benjamin; Rückert, Michael; Weber, Julia; Mayr, Xaver; Derer, Anja; Lotter, Michael; Bert, Christoph; Rödel, Franz; Fietkau, Rainer; Gaipl, Udo S.

    2017-01-01

    In addition to locally controlling the tumor, hypofractionated radiotherapy (RT) particularly aims to activate immune cells in the RT-modified microenvironment. Therefore, we examined whether hypofractionated RT can activate dendritic cells (DCs), induce immune cell infiltration in tumors, and how the chronology of immune cell migration into tumors occurs to gain knowledge for future definition of radiation breaks and inclusion of immunotherapy. Colorectal cancer treatments offer only limited survival benefit, and immunobiological principles for additional therapies need to be explored with preclinical models. The impact of hypofractionated RT on CT26 colon cancer tumor cell death, migration of DCs toward supernatants (SN) of tumor cells, and activation of DCs by SN were analyzed. The subcutaneous tumor of a BALB/c-CT26 mouse model was locally irradiated with 2 × 5 Gy, the tumor volume was monitored, and the infiltration of immune cells in the tumor was determined by flow cytometry daily. Hypofractionated RT induced a mixture of apoptotic and necrotic CT26 cells, which is known to be in particular immunogenic. DCs that migrated toward SN of CT26 cells particularly upregulated the activation markers CD80 and CD86 when in contact with SN of irradiated tumor cells. After hypofractionated RT, the tumor outgrowth was significantly retarded and in the irradiated tumors an increased infiltration of macrophages (CD11bhigh/F4-80+) and DCs (MHC-II+), but only between day 5 and 10 after the first irradiation, takes place. While CD4+ T cells migrated into non-irradiated and irradiated tumors, CD8+ T cells were only found in tumors that had been irradiated and they were highly increased at day 8 after the first irradiation. Myeloid-derived suppressor cells and regulatory T cells show regular turnover in irradiated and non-irradiated tumors. Tumor cell-specific anti-IgM antibodies were enhanced in the serum of animals with irradiated tumors. We conclude that

  7. Effect of anisotropy on stress-induced electrical potentials in bovine bone using ultrasound irradiation

    NASA Astrophysics Data System (ADS)

    Matsukawa, S.; Makino, T.; Mori, S.; Koyama, D.; Takayanagi, S.; Mizuno, K.; Yanagitani, T.; Matsukawa, M.

    2017-04-01

    The bone fracture healing mechanism of the low-intensity pulsed ultrasound technique is not yet clearly understood. In our previous study, the electrical potentials induced in bone were successfully measured by focusing on piezoelectricity in the MHz range. Bone is composed of collagen and hydroxyapatite and has strong anisotropy. The purpose of this study is to investigate the effects of bone anisotropy on the electrical potentials induced by ultrasound irradiation. For this study, ultrasound bone transducers were fabricated using cortical bovine bone plates as piezoelectric devices. An ultrasound of 7.4 kPapeak-peak (i.e., the peak-to-peak pressure value) was used to irradiate the side surface of each bone plate. Electrical potentials induced in the bone plate were then measured by varying the wave propagation direction in the plate. The peak-to-peak values of these ultrasonically induced electrical potentials were found to vary with changes in the ultrasound propagation direction in the bone sample. The potential was maximized at an inclination of approximately 45° to the bone axis but was minimized around the three orthogonal directions. These maxima and minima ranged from 28 to 33 μVpeak-peak and from 5 to 12 μVpeak-peak, respectively. Additionally, our ultrasound results indicated a change in polarity due to bone anisotropy in the MHz range.

  8. Continuous Exposure to Low-Dose-Rate Gamma Irradiation Reduces Airway Inflammation in Ovalbumin-Induced Asthma.

    PubMed

    Kim, Joong Sun; Son, Yeonghoon; Bae, Min Ji; Lee, Seung Sook; Park, Sun Hoo; Lee, Hae June; Lee, Soong In; Lee, Chang Geun; Kim, Sung Dae; Jo, Wol Soon; Kim, Sung Ho; Shin, In Sik

    2015-01-01

    Although safe doses of radiation have been determined, concerns about the harmful effects of low-dose radiation persist. In particular, to date, few studies have investigated the correlation between low-dose radiation and disease development. Asthma is a common chronic inflammatory airway disease that is recognized as a major public health problem. In this study, we evaluated the effects of low-dose-rate chronic irradiation on allergic asthma in a murine model. Mice were sensitized and airway-challenged with ovalbumin (OVA) and were exposed to continuous low-dose-rate irradiation (0.554 or 1.818 mGy/h) for 24 days after initial sensitization. The effects of chronic radiation on proinflammatory cytokines and the activity of matrix metalloproteinase-9 (MMP-9) were investigated. Exposure to low-dose-rate chronic irradiation significantly decreased the number of inflammatory cells, methylcholine responsiveness (PenH value), and the levels of OVA-specific immunoglobulin E, interleukin (IL)-4, and IL-5. Furthermore, airway inflammation and the mucus production in lung tissue were attenuated and elevated MMP-9 expression and activity induced by OVA challenge were significantly suppressed. These results indicate that low-dose-rate chronic irradiation suppresses allergic asthma induced by OVA challenge and does not exert any adverse effects on asthma development. Our findings can potentially provide toxicological guidance for the safe use of radiation and relieve the general anxiety about exposure to low-dose radiation.

  9. Ion irradiation induced nucleation and growth of nanoparticles in amorphous silicon carbide at elevated temperatures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Limin; Jiang, Weilin; Ai, Wensi

    Ion irradiation induced crystallization in as-deposited amorphous SiC films is investigated using grazing-angle incidence x-ray diffraction (GIXRD), transmission electron microscopy (TEM) and Raman spectroscopy. Irradiation with 5 MeV Xe to fluence of 115 Xe/nm2 at 700 K results in a homogenous distribution of 3C-SiC grains with an average crystallite size of ~5.7 nm over the entire film thickness (~1 μm). The nucleation and growth processes exhibit a weak dependence on dose in displacements per atom (dpa) in the dose range from 6 to 20 dpa. A transformation of homonuclear C-C bonds from sp3 to sp2 hybridization is observed in themore » irradiated films, which may be partly responsible for the observed grain size saturation. The results from this study may have a significant impact on synthesis of nanograins in amorphous SiC and other similar materials with effective control of grain size and density by ion irradiation.« less

  10. Comparison of small intestinal submucosa graft with split-thickness skin graft for cervicovaginal reconstruction of congenital vaginal and cervical aplasia.

    PubMed

    Shen, Fang; Zhang, Xu-Yin; Yin, Chu-Yang; Ding, Jing-Xin; Hua, Ke-Qin

    2016-11-01

    What is the difference in vaginal-length gain and resumption of menstruation following cervicovaginal reconstruction using split-thickness skin (STS) graft versus small intestinal submucosa (SIS) graft for patients with congenital vaginal and cervical aplasia? No difference was found in the number of patients who resumed menstruation between the two groups; however, significantly greater vaginal-length gain was found in the STS group. Hysterectomy and vaginoplasty are typically recommended for patients without a cervix or without a sufficient cervix to avoid postoperative re-obstruction. Advances in surgical techniques have enabled the use of autologous tissues or heterologous biological grafts for reconstructive procedures, allowing patients undergoing these procedures to preserve the possibility of conception. This was a retrospective study of 26 women who were diagnosed with congenital vaginal and cervical aplasia with a functional endometrial cavity and underwent cervicovaginal reconstruction using STS or SIS grafts between January 2012 and October 2015 at the Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China. 15 women underwent cervicovaginal reconstruction using SIS graft and 11 underwent cervicovaginal reconstruction using STS graft. Clinical characteristics, perioperative data, resumption of menstruation, vaginal stenosis, length of the neovagina, vaginal-length gain, stricture of the cervix and body image were postoperatively assessed. At a median follow-up of 21 (2-46) months, all but one of the patients experienced relief of abdominal pain and resumed menstruation. Re-obstruction of the cervix occurred in only one patient in the SIS group. The SIS group reported significantly higher body image scores and cosmetic satisfaction. Although the two groups had a similar vaginal length before surgery, the vaginal-length gain was significantly greater in the STS group (4.9 ± 1.7 cm in the SIS group versus 7.5 ± 0.7 cm in the STS group

  11. Proteolytic cleavage and activation of PAK2 during UV irradiation-induced apoptosis in A431 cells.

    PubMed

    Tang, T K; Chang, W C; Chan, W H; Yang, S D; Ni, M H; Yu, J S

    1998-09-15

    Exposure of mammalian cells to ultraviolet (UV) light elicits a cellular response and can also lead to apoptotic cell death. In this report, we show that a 36-kDa myelin basic protein (MBP) kinase detected by an in-gel kinase assay can be dramatically activated during the early stages of UV irradiation-triggered apoptosis of A431 cells. Immunoblot analysis revealed that this 36-kDa MBP kinase could be recognized by an antibody against the C-terminal regions of a family of p21Cdc42/Rac-activated kinases (PAKs). By using this antibody and a PAK2-specific antibody against the N-terminal region of PAK2 as studying tools, we further demonstrated that UV irradiation caused cleavage of PAK2 to generate a 36-kDa C-terminal catalytic fragment and a 30-kDa N-terminal fragment in A431 cells. The appearance of the 36-kDa C-terminal catalytic fragment of PAK2 matched exactly with the activation of the 36-kDa MBP kinase in A431 cells upon UV irradiation. In addition, UV irradiation also led to activation of CPP32/caspase-3, but not ICH-1L/caspase-2 and ICE/caspase-1, in A431 cells and the kinetics of activation of CPP32/caspase-3 appeared to correlate well with that of DNA fragmentation and of cleavage/activation of PAK2, respectively. Moreover, blockage of activation of CPP32/caspase-3 by pretreating the cells with two specific tetrapeptidic inhibitors for caspases (Ac-DEVD-cho and Ac-YVAD-cmk) could significantly attenuate the extent of cleavage/activation of PAK2 induced by UV irradiation. Collectively, the results demonstrate that cleavage and activation of PAK2 can be induced during the early stages of UV irradiation-triggered apoptosis and indicate the involvement of CPP32/caspase-3 in this process.

  12. Structural modifications induced by ion irradiation and temperature in boron carbide B4C

    NASA Astrophysics Data System (ADS)

    Victor, G.; Pipon, Y.; Bérerd, N.; Toulhoat, N.; Moncoffre, N.; Djourelov, N.; Miro, S.; Baillet, J.; Pradeilles, N.; Rapaud, O.; Maître, A.; Gosset, D.

    2015-12-01

    Already used as neutron absorber in the current French nuclear reactors, boron carbide (B4C) is also considered in the future Sodium Fast Reactors of the next generation (Gen IV). Due to severe irradiation conditions occurring in these reactors, it is of primary importance that this material presents a high structural resistance under irradiation, both in the ballistic and electronic damage regimes. Previous works have shown an important structural resistance of boron carbide even at high neutron fluences. Nevertheless, the structural modification mechanisms due to irradiation are not well understood. Therefore the aim of this paper is to study structural modifications induced in B4C samples in different damage regimes. The boron carbide pellets were shaped and sintered by using spark plasma sintering method. They were then irradiated in several conditions at room temperature or 800 °C, either by favoring the creation of ballistic damage (between 1 and 3 dpa), or by favoring the electronic excitations using 100 MeV swift iodine ions (Se ≈ 15 keV/nm). Ex situ micro-Raman spectroscopy and Doppler broadening of annihilation radiation technique with variable energy slow positrons were coupled to follow the evolution of the B4C structure under irradiation.

  13. The accidental mentor: Australian rural nurses developing supportive relationships in the workplace.

    PubMed

    Mills, J E; Francis, K; Bonner, A

    2007-01-01

    Like the fictional 'Accidental Tourist', an author who does not plan to write about travel, the accidental mentor is an experienced rural nurse who does not plan to be a mentor, and yet assumes that role with new or novice rural nurses as a result of them encountering a critical incident. Accidental mentoring is a short-term relationship that provides support for the new or novice nurse in managing the incident, while maintaining their level of confidence. This article describes the findings from a constructivist grounded theory study that examined Australian rural nurses' experiences of mentoring, including evidence for a new concept of mentoring - accidental mentoring. Constructivist grounded theory is a research methodology that focuses on issues of importance for participants around an area of common interest - in this case Australian rural nurse mentoring. In this study, seven participants were interviewed, generating nine transcripts. These were analysed using a process of concurrent data generation and analysis. In addition, the literature regarding rural nurse workforce and mentoring was incorporated as a source of data, using collective frame analysis. Rural nurses live their work, which predisposes them to developing supportive relationships with new or novice rural nurses. Supportive relationships range from preceptoring, to accidental mentoring, mentoring and deep friendship, depending on the level of trust and engagement that is established between the partners and the amount of time they spend together. Accidental mentoring is a short-term relationship that is prompted by experienced rural nurses observing a new or novice rural nurse experiencing a critical incident. Findings are presented that illustrate a new concept of accidental mentoring not present in the current literature around nurse mentoring. A series of recommendations are included that suggest strategies for improved rural nurse retention as an outcome of recognising and developing such

  14. Administration of the peroxisomal proliferator-activated receptor {gamma} agonist pioglitazone during fractionated brain irradiation prevents radiation-induced cognitive impairment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao Weiling; Payne, Valerie; Tommasi, Ellen

    2007-01-01

    Purpose: We hypothesized that administration of the anti-inflammatory peroxisomal proliferator-activated receptor {gamma} (PPAR{gamma}) agonist pioglitazone (Pio) to adult male rats would inhibit radiation-induced cognitive impairment. Methods and Materials: Young adult male F344 rats received one of the following: (1) fractionated whole brain irradiation (WBI); 40 or 45 Gy {gamma}-rays in 4 or 4.5 weeks, respectively, two fractions per week and normal diet; (2) sham-irradiation and normal diet; (3) WBI plus Pio (120 ppm) before, during, and for 4 or 54 weeks postirradiation; (4) sham-irradiation plus Pio; or (5) WBI plus Pio starting 24h after completion of WBI. Results: Administration ofmore » Pio before, during, and for 4 or 54 weeks after WBI prevented Radiation-induced cognitive impairment. Administration of Pio for 54 weeks starting after completion of fractionated WBI substantially but not significantly reduced Radiation-induced cognitive impairment. Conclusions: These findings offer the promise of improving the quality of life and increasing the therapeutic window for brain tumor patients.« less

  15. In Vivo Imaging Reveals Significant Tumor Vascular Dysfunction and Increased Tumor Hypoxia-Inducible Factor-1α Expression Induced by High Single-Dose Irradiation in a Pancreatic Tumor Model

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maeda, Azusa; Department of Medical Biophysics, University of Toronto, Toronto, Ontario; Chen, Yonghong

    Purpose: To investigate the effect of high-dose irradiation on pancreatic tumor vasculature and microenvironment using in vivo imaging techniques. Methods and Materials: A BxPC3 pancreatic tumor xenograft was established in a dorsal skinfold window chamber model and a subcutaneous hind leg model. Tumors were irradiated with a single dose of 4, 12, or 24 Gy. The dorsal skinfold window chamber model was used to assess tumor response, vascular function and permeability, platelet and leukocyte adhesion to the vascular endothelium, and tumor hypoxia for up to 14 days after 24-Gy irradiation. The hind leg model was used to monitor tumor size, hypoxia, and vascularitymore » for up to 65 days after 24-Gy irradiation. Tumors were assessed histologically to validate in vivo observations. Results: In vivo fluorescence imaging revealed temporary vascular dysfunction in tumors irradiated with a single dose of 4 to 24 Gy, but most significantly with a single dose of 24 Gy. Vascular functional recovery was observed by 14 days after irradiation in a dose-dependent manner. Furthermore, irradiation with 24 Gy caused platelet and leukocyte adhesion to the vascular endothelium within hours to days after irradiation. Vascular permeability was significantly higher in irradiated tumors compared with nonirradiated controls 14 days after irradiation. This observation corresponded with increased expression of hypoxia-inducible factor-1α in irradiated tumors. In the hind leg model, irradiation with a single dose of 24 Gy led to tumor growth delay, followed by tumor regrowth. Conclusions: Irradiation of the BxPC3 tumors with a single dose of 24 Gy caused transient vascular dysfunction and increased expression of hypoxia-inducible factor-1α. Such biological changes may impact tumor response to high single-dose and hypofractionated irradiation, and further investigations are needed to better understand the clinical outcomes of stereotactic body radiation therapy.« less

  16. Nanoparticles alloying in liquids: Laser-ablation-generated Ag or Pd nanoparticles and laser irradiation-induced AgPd nanoparticle alloying

    NASA Astrophysics Data System (ADS)

    Semaltianos, N. G.; Chassagnon, R.; Moutarlier, V.; Blondeau-Patissier, V.; Assoul, M.; Monteil, G.

    2017-04-01

    Laser irradiation of a mixture of single-element micro/nanomaterials may lead to their alloying and fabrication of multi-element structures. In addition to the laser induced alloying of particulates in the form of micro/nanopowders in ambient atmosphere (which forms the basis of the field of additive manufacturing technology), another interesting problem is the laser-induced alloying of a mixture of single-element nanoparticles in liquids since this process may lead to the direct fabrication of alloyed-nanoparticle colloidal solutions. In this work, bare-surface ligand-free Ag and Pd nanoparticles in solution were prepared by laser ablation of the corresponding bulk target materials, separately in water. The two solutions were mixed and the mixed solution was laser irradiated for different time durations in order to investigate the laser-induced nanoparticles alloying in liquid. Nanoparticles alloying and the formation of AgPd alloyed nanoparticles takes place with a decrease of the intensity of the surface-plasmon resonance peak of the Ag nanoparticles (at ∼405 nm) with the irradiation time while the low wavelength interband absorption peaks of either Ag or Pd nanoparticles remain unaffected by the irradiation for a time duration even as long as 30 min. The nanoalloys have lattice constants with values between those of the pure metals, which indicates that they consist of Ag and Pd in an approximately 1:1 ratio similar to the atomic composition of the starting mixed-nanoparticle solution. Formation of nanoparticle networks consisting of bimetallic alloyed nanoparticles and nanoparticles that remain as single elements (even after the end of the irradiation), joining together, are also formed. The binding energies of the 3d core electrons of both Ag and Pd nanoparticles shift to lower energies with the irradiation time, which is also a typical characteristic of AgPd alloyed nanoparticles. The mechanisms of nanoparticles alloying and network formation are also

  17. Nanoparticles alloying in liquids: Laser-ablation-generated Ag or Pd nanoparticles and laser irradiation-induced AgPd nanoparticle alloying.

    PubMed

    Semaltianos, N G; Chassagnon, R; Moutarlier, V; Blondeau-Patissier, V; Assoul, M; Monteil, G

    2017-04-18

    Laser irradiation of a mixture of single-element micro/nanomaterials may lead to their alloying and fabrication of multi-element structures. In addition to the laser induced alloying of particulates in the form of micro/nanopowders in ambient atmosphere (which forms the basis of the field of additive manufacturing technology), another interesting problem is the laser-induced alloying of a mixture of single-element nanoparticles in liquids since this process may lead to the direct fabrication of alloyed-nanoparticle colloidal solutions. In this work, bare-surface ligand-free Ag and Pd nanoparticles in solution were prepared by laser ablation of the corresponding bulk target materials, separately in water. The two solutions were mixed and the mixed solution was laser irradiated for different time durations in order to investigate the laser-induced nanoparticles alloying in liquid. Nanoparticles alloying and the formation of AgPd alloyed nanoparticles takes place with a decrease of the intensity of the surface-plasmon resonance peak of the Ag nanoparticles (at ∼405 nm) with the irradiation time while the low wavelength interband absorption peaks of either Ag or Pd nanoparticles remain unaffected by the irradiation for a time duration even as long as 30 min. The nanoalloys have lattice constants with values between those of the pure metals, which indicates that they consist of Ag and Pd in an approximately 1:1 ratio similar to the atomic composition of the starting mixed-nanoparticle solution. Formation of nanoparticle networks consisting of bimetallic alloyed nanoparticles and nanoparticles that remain as single elements (even after the end of the irradiation), joining together, are also formed. The binding energies of the 3d core electrons of both Ag and Pd nanoparticles shift to lower energies with the irradiation time, which is also a typical characteristic of AgPd alloyed nanoparticles. The mechanisms of nanoparticles alloying and network formation are also

  18. Irradiation of skin with visible light induces reactive oxygen species and matrix-degrading enzymes.

    PubMed

    Liebel, Frank; Kaur, Simarna; Ruvolo, Eduardo; Kollias, Nikiforos; Southall, Michael D

    2012-07-01

    Daily skin exposure to solar radiation causes cells to produce reactive oxygen species (ROS), which are a primary factor in skin damage. Although the contribution of the UV component to skin damage has been established, few studies have examined the effects of non-UV solar radiation on skin physiology. Solar radiation comprises <10% of UV, and thus the purpose of this study was to examine the physiological response of skin to visible light (400-700 nm). Irradiation of human skin equivalents with visible light induced production of ROS, proinflammatory cytokines, and matrix metalloproteinase (MMP)-1 expression. Commercially available sunscreens were found to have minimal effects on reducing visible light-induced ROS, suggesting that UVA/UVB sunscreens do not protect the skin from visible light-induced responses. Using clinical models to assess the generation of free radicals from oxidative stress, higher levels of free radical activity were found after visible light exposure. Pretreatment with a photostable UVA/UVB sunscreen containing an antioxidant combination significantly reduced the production of ROS, cytokines, and MMP expression in vitro, and decreased oxidative stress in human subjects after visible light irradiation. Taken together, these findings suggest that other portions of the solar spectrum aside from UV, particularly visible light, may also contribute to signs of premature photoaging in skin.

  19. Bone marrow transplantation in a patient with drug-induced aplastic anemia.

    PubMed

    Banerjee, T K; Band, P R; Pabst, H; Goldsand, G; Armstrong, W D; Brown, J; Hill, J R; Dossetor, J B

    1972-09-09

    A 23-year-old woman gravely ill with Pseudomonas septicemia secondary to presumed drug-induced bone marrow aplasia received marrow transplantation from two male HL-A identical sibling donors. She had a successful engraftment with excellent but temporary clinical improvement. Subsequently she succumbed to graft-versus-host disease manifested by Pseudomonas and Candida albicans septicemia, cytomegalovirus pneumonitis, three phases of dermatitis, nausea, vomiting, dysphagia, diarrhea, fever, edema and bone pain, with gradual but complete graft suppression by the 74th day after the transplantation. A second marrow transplant on the 70th day was unsuccessful.

  20. Loss of cellular transformation efficiency induced by DNA irradiation with low-energy (10 eV) electrons.

    PubMed

    Kouass Sahbani, Saloua; Sanche, Leon; Cloutier, Pierre; Bass, Andrew D; Hunting, Darel J

    2014-11-20

    Low energy electrons (LEEs) of energies less than 20 eV are generated in large quantities by ionizing radiation in biological matter. While LEEs are known to induce single (SSBs) and double strand breaks (DSBs) in DNA, their ability to inactivate cells by inducing nonreparable lethal damage has not yet been demonstrated. Here we observe the effect of LEEs on the functionality of DNA, by measuring the efficiency of transforming Escherichia coli with a [pGEM-3Zf (-)] plasmid irradiated with 10 eV electrons. Highly ordered DNA films were prepared on pyrolitic graphite by molecular self-assembly using 1,3-diaminopropane ions (Dap(2+)). The uniformity of these films permits the inactivation of approximately 50% of the plasmids compared to <10% using previous methods, which is sufficient for the subsequent determination of their functionality. Upon LEE irradiation, the fraction of functional plasmids decreased exponentially with increasing electron fluence, while LEE-induced isolated base damage, frank DSB, and non DSB-cluster damage increased linearly with fluence. While DSBs can be toxic, their levels were too low to explain the loss of plasmid functionality observed upon LEE irradiation. Similarly, non-DSB cluster damage, revealed by transforming cluster damage into DSBs by digestion with repair enzymes, also occurred relatively infrequently. The exact nature of the lethal damage remains unknown, but it is probably a form of compact cluster damage in which the lesions are too close to be revealed by purified repair enzymes. In addition, this damage is either not repaired or is misrepaired by E. coli, since it results in plasmid inactivation, when they contain an average of three lesions. Comparison with previous results from a similar experiment performed with γ-irradiated plasmids indicates that the type of clustered DNA lesions, created directly on cellular DNA by LEEs, may be more difficult to repair than those produced by other species from radiolysis.

  1. Ectrodactyly with aplasia of long bones (OMIM; 119100) in a large inbred Arab family with an apparent autosomal dominant inheritance and reduced penetrance: clinical and genetic analysis.

    PubMed

    Naveed, Mohammed; Al-Ali, Mahmoud T; Murthy, Sabita K; Al-Hajali, Sarah; Al-Khaja, Najib; Deutsch, Samuel; Bottani, Armand; Antonarakis, Stylianos E; Nath, Swapan K; Radhakrishna, Uppala

    2006-07-01

    Ectrodactyly with aplasia of long bones syndrome is one of the most recognizable defects involving the extremities. We have studied a very large eight-generation consanguineous Arab family from the United Arab Emirates (UAE) with multiple severe limb anomalies resembling this condition (OMIM; 119100), for which the affected gene is unknown. The pedigree consists of 145 individuals including 23 affected (14 males/9 females) with limb anomalies. Of these, 18 had tibial aplasia (TA) usually on the right side. The expression of the phenotype was variable and ranged from bilateral to unilateral TA with ectrodactyly and other defects of the extremities. The mode of inheritance appears to be autosomal dominant with reduced penetrance. There were 10 consanguineous marriages observed in this pedigree. This could suggest possible pseudodominance due to high frequency of the mutant allele. Candidate loci for the described syndrome include GLI3 (OMIM: 165240) on 7p13, sonic hedgehog; (OMIM: 600725) on 7q36, Langer-Giedion syndrome (OMIM: 150230) on 8q24.1 and split-hand/foot malformation 3 (OMIM: 600095) on 10q24. In addition, bilateral tibial hemimelia and unilateral absence of the ulna was previously observed to co-segregate with deletion of 8q24.1. Two-point linkage and haplotype analyses did not show the involvement of the above regions in this family. (c) 2006 Wiley-Liss, Inc.

  2. Chromosomal instability induced by heavy ion irradiation

    NASA Technical Reports Server (NTRS)

    Limoli, C. L.; Ponnaiya, B.; Corcoran, J. J.; Giedzinski, E.; Morgan, W. F.

    2000-01-01

    PURPOSE: To establish the dose-response relationship for the induction of chromosomal instability in GM10115 cells exposed to high-energy iron ions (1 GeV/nucleon, mean LET 146 keV/microm) and gold ions (11 GeV/nucleon, mean LET 1450 keV/microm). Past work has established that sparsely ionizing X-rays can induce a long-lived destabilization of chromosomes in a dose-dependent manner at an incidence of approximately 3% per gray. The present investigation assesses the capacity of High-Z and High-energy (HZE) particles to elicit this same endpoint. MATERIALS AND METHODS: Clonal populations derived from single progenitor cells surviving heavy-ion irradiation were analyzed cytogenetically to identify those clones showing a persistent destablization of chromosomes. RESULTS: Dose-response data, with a particular emphasis at low dose (< 1.0 Gy), indicate a frequency of approximately 4% per gray for the induction of chromosomal instability in clones derived from single progenitor cells surviving exposure to iron ions. The induction of chromosomal instability by gold ions was, however, less responsive to applied dose, as the observed incidence of this phenotype varied from 0 to 10% over 1-8 Gy. Both iron and gold ions gave dose-dependent increases in the yield of chromosomal aberrations (both chromosome- and chromatid-type) measured at the first mitosis following irradiation, as well as shoulderless survival curves having D0=0.87 and 1.1 Gy respectively. CONCLUSIONS: Based on the present dose-response data, the relative biological effectiveness of iron ions is 1.3 for the induction of chromosomal instability, and this indicates that heavy ions are only slightly more efficient than X-rays at eliciting this delayed phenotype.

  3. Accidental intrathecal injection of magnesium sulfate for cesarean section

    PubMed Central

    Gilani, Mehryar Taghavi; Zirak, Nahid; Razavi, Majid

    2014-01-01

    Magnesium sulfate is used frequently in the operation room and risks of wrong injection should be considered. A woman with history of pseudocholinesterase enzyme deficiency in the previous surgery was referred for cesarean operation. Magnesium sulfate of 700 mg (3.5 ml of 20% solution) was accidentally administered in the subarachnoid space. First, the patient had warm sensation and cutaneous anesthesia, but due to deep tissue pain, general anesthesia was induced by thiopental and atracurium. After the surgery, muscle relaxation and lethargy remained. At 8-10 h later, muscle strength improved and train of four (TOF) reached over 0.85, and then the endotracheal tube was removed. The patient was evaluated during the hospital stay and on the anesthesia clinic. No neurological symptoms, headache or backache were reported. Due to availability of magnesium sulfate, we should be careful for inadvertent intravenous, spinal and epidural injection; therefore before injection must be double checked. PMID:25422620

  4. Accidental intrathecal injection of magnesium sulfate for cesarean section.

    PubMed

    Gilani, Mehryar Taghavi; Zirak, Nahid; Razavi, Majid

    2014-10-01

    Magnesium sulfate is used frequently in the operation room and risks of wrong injection should be considered. A woman with history of pseudocholinesterase enzyme deficiency in the previous surgery was referred for cesarean operation. Magnesium sulfate of 700 mg (3.5 ml of 20% solution) was accidentally administered in the subarachnoid space. First, the patient had warm sensation and cutaneous anesthesia, but due to deep tissue pain, general anesthesia was induced by thiopental and atracurium. After the surgery, muscle relaxation and lethargy remained. At 8-10 h later, muscle strength improved and train of four (TOF) reached over 0.85, and then the endotracheal tube was removed. The patient was evaluated during the hospital stay and on the anesthesia clinic. No neurological symptoms, headache or backache were reported. Due to availability of magnesium sulfate, we should be careful for inadvertent intravenous, spinal and epidural injection; therefore before injection must be double checked.

  5. [Accidental hypothermia].

    PubMed

    Soteras Martínez, Iñigo; Subirats Bayego, Enric; Reisten, Oliver

    2011-07-09

    Accidental hypothermia is an infrequent and under-diagnosed pathology, which causes fatalities every year. Its management requires thermometers to measure core temperature. An esophageal probe may be used in a hospital situation, although in moderate hypothermia victims epitympanic measurement is sufficient. Initial management involves advance life support and body rewarming. Vigorous movements can trigger arrhythmia which does not use to respond to medication or defibrillation until the body reaches 30°C. External, passive rewarming is the method of choice for mild hypothermia and a supplementary method for moderate or severe hypothermia. Active external rewarming is indicated for moderate or severe hypothermia or mild hypothermia that has not responded to passive rewarming. Active internal rewarming is indicated for hemodynamically stable patients suffering moderate or severe hypothermia. Patients with severe hypothermia, cardiac arrest or with a potassium level below 12 mmol/l may require cardiopulmonary bypass treatment. Copyright © 2010 Elsevier España, S.L. All rights reserved.

  6. Measuring the visual salience of alignments by their non-accidentalness.

    PubMed

    Blusseau, S; Carboni, A; Maiche, A; Morel, J M; Grompone von Gioi, R

    2016-09-01

    Quantitative approaches are part of the understanding of contour integration and the Gestalt law of good continuation. The present study introduces a new quantitative approach based on the a contrario theory, which formalizes the non-accidentalness principle for good continuation. This model yields an ideal observer algorithm, able to detect non-accidental alignments in Gabor patterns. More precisely, this parameterless algorithm associates with each candidate percept a measure, the Number of False Alarms (NFA), quantifying its degree of masking. To evaluate the approach, we compared this ideal observer with the human attentive performance on three experiments of straight contours detection in arrays of Gabor patches. The experiments showed a strong correlation between the detectability of the target stimuli and their degree of non-accidentalness, as measured by our model. What is more, the algorithm's detection curves were very similar to the ones of human subjects. This fact seems to validate our proposed measurement method as a convenient way to predict the visibility of alignments. This framework could be generalized to other Gestalts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Water accelerated transformation of d-limonene induced by ultraviolet irradiation and air exposure.

    PubMed

    Li, Li Jun; Hong, Peng; Jiang, Ze Dong; Yang, Yuan Fan; Du, Xi Ping; Sun, Hao; Wu, Li Ming; Ni, Hui; Chen, Feng

    2018-01-15

    d-Limonene is a fragrant chemical that widely exists in aromatic products. Isotopic labelling of water molecules plus GC-MS and GC-PCI-Q-TOF analyses were used to investigate the influence of water molecules on chemical transformation of d-limonene induced by UV irradiation and air exposure. The results showed that the synergistic effect of UV irradiation, air exposure and water presence could facilitate d-limonene transformation into the limonene oxides: p-mentha-2,8-dienols, hydroperoxides, carveols, l-carvone and carvone oxide. UV irradiation, air exposure, or water alone, however, caused negligible d-limonene transformation. With the aid of isotopic labelling of water and oxygen molecules, it was found that water molecules were split into hydrogen radicals and hydroxyl radicals, and the hydrogen radicals, in particular, promoted the transformation reactions. This study has elucidated the mechanism and factors that influence the transformation of d-limonene, which will benefit industries involved in production and storage of d-limonene-containing products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Accidental Head Injury: A Real Life Experience.

    ERIC Educational Resources Information Center

    Blakely, Jim

    1988-01-01

    The adult victim of accidental head injury as a result of an automobile accident recounts his experiences as a brain injured adult with such problems as poor balance, poor speech, spasticity, and lack of fine motor movement. He emphasizes his determination to get on with his life. (DB)

  9. Paediatric femur fractures at the emergency department: accidental or not?

    PubMed Central

    Vrolijk-Bosschaart, Thekla F; Bakx, Roel; Van Rijn, Rick R.

    2016-01-01

    Only a small proportion of all paediatric fractures is caused by child abuse or neglect, especially in highly prevalent long bone fractures. It can be difficult to differentiate abusive fractures from non-abusive fractures. This article focuses on femoral fractures in young children. Based on three cases, this article presents a forensic evidence-based approach to differentiate between accidental and non-accidental causes of femoral fractures. We describe three cases of young children who were presented to the emergency department because of a suspected femur fracture. Although in all cases, the fracture had a similar location and appearance, the clinical history and developmental stage of the child led to three different conclusions. In the first two cases, an accidental mechanism was a plausible conclusion, although in the second case, neglect of parental supervision was the cause for concern. In the third case, a non-accidental injury was diagnosed and appropriate legal prosecution followed. Any doctor treating children should always be aware of the possibility of child abuse and neglect in children with injuries, especially in young and non-mobile children presenting with an unknown trauma mechanism. If a suspicion of child abuse or neglect arises, a thorough diagnostic work-up should be performed, including a full skeletal survey according to the guidelines of the Royal College of Radiologists and the Royal College of Paediatrics and Child Health. In order to make a good assessment, the radiologist reviewing the skeletal survey needs access to all relevant clinical and social information. PMID:26642309

  10. Risk assessment for stonecutting enterprises Accidental risks in the course of petroleum production and stone extraction

    NASA Astrophysics Data System (ADS)

    Aleksandrova, A. J.; Timofeeva, S. S.

    2018-01-01

    The paper is devoted to the assessment of accidental risks occurring at the works engaged in stone extracting and petroleum production. Two basic kinds of accidents common for stone extracting and petroleum production have been chosen to be discussed in the part under consideration. The most dangerous accidental situation characteristic for a stone milling line is an unsanctioned explosion, UE, of blasting agents used for the development of stone deposits. The analysis of a risk occurrence in certain accidental situations is to be carried out. With reference to petroleum extraction, a combustibles and lubricants (C & L) explosion is the most dangerous of characteristic accidental situations. To reveal the most probable causes of accidental situations to be realized, a graph of cause and effect relations has been constructed for each of the accidental situations most probable causes to real situation of an accident. Disasters of a natural origin are the most probable causes of unsanctioned explosions at the deposits of stone raw materials. Technology related natural disasters are the most probable causes of unsanctioned explosions to be realized at multiple well platforms engaged in petroleum production.

  11. Accidental poisoning with detomidine and butorphanol.

    PubMed

    Hannah, N

    2010-09-01

    This is a case report concerning a veterinarian who spilled detomidine and butorphanol on dermatitic hands while sedating a horse. This resulted in acute poisoning from which the patient spontaneously recovered with supportive management. Veterinarians often suffer from occupational dermatitis and handle strong sedatives with no gloves while working around unpredictable animals. Thus, this group is at risk of accidental self-poisoning from this method.

  12. Accidental hypothermia in a healthy quadriplegic patient.

    PubMed

    Altus, P; Hickman, J W; Nord, H J

    1985-03-01

    An otherwise healthy 28-year-old quadriplegic patient was admitted to the hospital with a core temperature of 76 degrees F secondary to accidental hypothermia. Her neurologic disability was detrimental to thermoregulation by decreasing her ability to shiver actively and to vasoconstrict. The relationship between shivering and thermoregulation is discussed.

  13. Effect of infrared laser irradiation on amino acid neurotransmitters in an epileptic animal model induced by pilocarpine.

    PubMed

    Radwan, Nasr Mahmoud; El Hay Ahmed, Nawal Abd; Ibrahim, Khayria Mansour; Khedr, Mona Emam; Aziz, Mona A; Khadrawy, Yasser Ashry

    2009-06-01

    The aim of the present study was to investigate the effect of daily laser irradiation on the levels of amino acid neurotransmitters in the cortex and hippocampus in an epileptic animal model induced by pilocarpine. It has been claimed that at specific wavelengths and energy densities, laser irradiation is a novel and useful tool for the treatment of peripheral and central nervous system injuries and disorders. Adult male albino rats were divided into three groups: control rats, pilocarpinized rats (epileptic animal model), and pilocarpinized rats treated daily with laser irradiation (90 mW at 830 nm) for 7 d. The following parameters were assayed in cortex and hippocampus: amino acid neurotransmitters (excitatory: glutamic acid and aspartate; and inhibitory: gamma-aminobutyric acid [GABA], glycine, and taurine) by high-performance liquid chromatography (HPLC), glucose content, and the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), using a spectrophotometer. Significant increases in the concentrations of glutamic acid, glutamine, glycine, and taurine were recorded in the cortices of pilocarpinized rats, and they returned to initial levels after laser treatment. In the hippocampus, a moderate increase in aspartate accompanied by a significant increase in glycine were observed in the epileptic animal model, and these dropped to near-control values after laser treatment. In addition, a significant increase in cortical AST activity and a significant decrease in ALT activity and glucose content were obtained in the pilocarpinized animals and pilocarpinized rats treated with laser irradiation. In the hippocampus, significant decreases in the activity of AST and ALT and glucose content were recorded in the epileptic animals and in the epileptic animals treated with laser irradiation. Based on the results obtained in this study, it may be suggested that nearinfrared laser irradiation may reverse the neurochemical changes in amino acid

  14. Glioma Cell Death Induced by Irradiation or Alkylating Agent Chemotherapy Is Independent of the Intrinsic Ceramide Pathway

    PubMed Central

    Gramatzki, Dorothee; Herrmann, Caroline; Happold, Caroline; Becker, Katrin Anne; Gulbins, Erich; Weller, Michael; Tabatabai, Ghazaleh

    2013-01-01

    Background/Aims Resistance to genotoxic therapy is a characteristic feature of glioma cells. Acid sphingomyelinase (ASM) hydrolyzes sphingomyelin to ceramide and glucosylceramide synthase (GCS) catalyzes ceramide metabolism. Increased ceramide levels have been suggested to enhance chemotherapy-induced death of cancer cells. Methods Microarray and clinical data for ASM and GCS in astrocytomas WHO grade II–IV were acquired from the Rembrandt database. Moreover, the glioblastoma database of the Cancer Genome Atlas network (TCGA) was used for survival data of glioblastoma patients. For in vitro studies, increases in ceramide levels were achieved either by ASM overexpression or by the GCS inhibitor DL-threo-1-phenyl-2-palmitoylamino-3-morpholino-1-propanol (PPMP) in human glioma cell lines. Combinations of alkylating chemotherapy or irradiation and ASM overexpression, PPMP or exogenous ceramide were applied in parental cells. The anti-glioma effects were investigated by assessing proliferation, metabolic activity, viability and clonogenicity. Finally, viability and clonogenicity were assessed in temozolomide (TMZ)-resistant cells upon treatment with PPMP, exogenous ceramide, alkylating chemotherapy, irradiation or their combinations. Results Interrogations from the Rembrandt and TCGA database showed a better survival of glioblastoma patients with low expression of ASM or GCS. ASM overexpression or PPMP treatment alone led to ceramide accumulation but did not enhance the anti-glioma activity of alkylating chemotherapy or irradiation. PPMP or exogenous ceramide induced acute cytotoxicity in glioblastoma cells. Combined treatments with chemotherapy or irradiation led to additive, but not synergistic effects. Finally, no synergy was found when TMZ-resistant cells were treated with exogenous ceramide or PPMP alone or in combination with TMZ or irradiation. Conclusion Modulation of intrinsic glioma cell ceramide levels by ASM overexpression or GCS inhibition does not

  15. Irradiation-induced defect formation and damage accumulation in single crystal CeO2

    NASA Astrophysics Data System (ADS)

    Graham, Joseph T.; Zhang, Yanwen; Weber, William J.

    2018-01-01

    The accumulation of irradiation-induced disorder in single crystal CeO2 has been investigated over a wide range of ion fluences. Room temperature irradiations of epitaxial CeO2 thin films using 2 MeV Au2+ ions were carried out up to a total fluence of 1.3 ×1016 cm-2 Post-irradiation disorder was characterized using ion channeling Rutherford backscattering spectrometry (RBS/C) and confocal Raman spectroscopy. The Raman measurements were interpreted by means of a phonon confinement model, which employed rigid ion calculations to determine the phonon correlation length in the irradiated material. Comparison between the dose dependent changes in correlation length of the Raman measurements and the Ce disorder fraction from RBS/C provides complementary quantitative details on the rate of point and extended defect formation on the Ce and O sub-lattices over a broad range of ion fluences. Raman measurements, which are significantly more sensitive than RBS/C at low doses, reveal that the nucleation rate of defects is highest below 0.1 displacements per atom (dpa). Comparison between Raman and RBS/C measurements suggests that between 0.1 and 10 dpa the damage evolution is characterized by modest growth of point defects and/or small clusters, while above 10 dpa the preexisting defects rapidly grow into extended clusters and/or loops.

  16. Irradiation-induced defect formation and damage accumulation in single crystal CeO 2

    DOE PAGES

    Graham, Joseph T.; Zhang, Yanwen; Weber, William J.

    2017-11-15

    Here, the accumulation of irradiation-induced disorder in single crystal CeO 2 has been investigated over a wide range of ion fluences. Room temperature irradiations of epitaxial CeO 2 thin films using 2 MeV Au 2+ ions were carried out up to a total fluence of 1.3 x 10 16 cm –2 Post-irradiation disorder was characterized using ion channeling Rutherford backscattering spectrometry (RBS/C) and confocal Raman spectroscopy. The Raman measurements were interpreted by means of a phonon confinement model, which employed rigid ion calculations to determine the phonon correlation length in the irradiated material. Comparison between the dose dependent changes inmore » correlation length of the Raman measurements and the Ce disorder fraction from RBS/C provides complementary quantitative details on the rate of point and extended defect formation on the Ce and O sub-lattices over a broad range of ion fluences. Raman measurements, which are significantly more sensitive than RBS/C at low doses, reveal that the nucleation rate of defects is highest below 0.1 displacements per atom (dpa). Comparison between Raman and RBS/C measurements suggests that between 0.1 and 10 dpa the damage evolution is characterized by modest growth of point defects and/or small clusters, while above 10 dpa the preexisting defects rapidly grow into extended clusters and/or loops.« less

  17. Irradiation-induced defect formation and damage accumulation in single crystal CeO 2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Graham, Joseph T.; Zhang, Yanwen; Weber, William J.

    Here, the accumulation of irradiation-induced disorder in single crystal CeO 2 has been investigated over a wide range of ion fluences. Room temperature irradiations of epitaxial CeO 2 thin films using 2 MeV Au 2+ ions were carried out up to a total fluence of 1.3 x 10 16 cm –2 Post-irradiation disorder was characterized using ion channeling Rutherford backscattering spectrometry (RBS/C) and confocal Raman spectroscopy. The Raman measurements were interpreted by means of a phonon confinement model, which employed rigid ion calculations to determine the phonon correlation length in the irradiated material. Comparison between the dose dependent changes inmore » correlation length of the Raman measurements and the Ce disorder fraction from RBS/C provides complementary quantitative details on the rate of point and extended defect formation on the Ce and O sub-lattices over a broad range of ion fluences. Raman measurements, which are significantly more sensitive than RBS/C at low doses, reveal that the nucleation rate of defects is highest below 0.1 displacements per atom (dpa). Comparison between Raman and RBS/C measurements suggests that between 0.1 and 10 dpa the damage evolution is characterized by modest growth of point defects and/or small clusters, while above 10 dpa the preexisting defects rapidly grow into extended clusters and/or loops.« less

  18. Accidental introductions of natural enemies: causes and implications

    USDA-ARS?s Scientific Manuscript database

    Accidental introductions of natural enemies, including parasitoid and predatory groups, may exceed species introduced intentionally. Several factors favor this: a general surge in international trade; lack of surveillance for species that are not associated with live plants or animals; inability to ...

  19. Topologically trivial and nontrivial edge bands in graphene induced by irradiation

    NASA Astrophysics Data System (ADS)

    Yang, Mou; Cai, Zhi-Jun; Wang, Rui-Qiang; Bai, Yan-Kui

    2016-08-01

    We proposed a minimal model to describe the Floquet band structure of two-dimensional materials with light-induced resonant inter-band transition. We applied it to graphene to study the band features caused by the light irradiation. Linearly polarized light induces pseudo gaps (gaps are functions of wavevector), and circularly polarized light causes real gaps on the quasi-energy spectrum. If the polarization of light is linear and along the longitudinal direction of zigzag ribbons, flat edge bands appear in the pseudo gaps, and if it is in the lateral direction of armchair ribbons, curved edge bands can be found. For the circularly polarized cases, edge bands arise and intersect in the gaps of both types of ribbons. The edge bands induced by the circularly polarized light are helical and those by linearly polarized light are topologically trivial ones. The Chern number of the Floquet band, which reflects the number of pairs of helical edge bands in graphene ribbons, can be reduced into the winding number at resonance.

  20. Limb/pelvis hypoplasia/aplasia with skull defect (Schinzel phocomelia): distinctive features and prenatal detection.

    PubMed

    Olney, R S; Hoyme, H E; Roche, F; Ferguson, K; Hintz, S; Madan, A

    2001-11-01

    Schinzel phocomelia syndrome is characterized by limb/pelvis hypoplasia/aplasia: specifically, intercalary limb deficiencies and absent or hypoplastic pelvic bones. The phenotype is similar to that described in a related multiple malformation syndrome known as Al-Awadi/Raas-Rothschild syndrome. The additional important feature of large parietooccipital skull defects without meningocele, encephalocele, or other brain malformation has thus far been reported only in children with Schinzel phocomelia syndrome. We recently evaluated a boy affected with Schinzel phocomelia born to nonconsanguineous healthy parents of Mexican origin. A third-trimester fetal ultrasound scan showed severe limb deficiencies and an absent pelvis. The infant died shortly after birth. Dysmorphology examination, radiographs, and autopsy revealed quadrilateral intercalary limb deficiencies with preaxial toe polydactyly; an absent pelvis and a 7 x 3-cm skull defect; and extraskeletal anomalies including microtia, telecanthus, micropenis with cryptorchidism, renal cysts, stenosis of the colon, and a cleft alveolar ridge. A normal 46,XY karyotype was demonstrated, and autosomal recessive inheritance was presumed on the basis of previously reported families. This case report emphasizes the importance of recognizing severe pelvic and skull deficiencies (either post- or prenatally) in differentiating infants with Schinzel phocomelia from other multiple malformation syndromes that feature intercalary limb defects, including thalidomide embryopathy and Roberts-SC phocomelia. Copyright 2001 Wiley-Liss, Inc.

  1. Jeju ground water containing vanadium induced immune activation on splenocytes of low dose γ-rays-irradiated mice.

    PubMed

    Ha, Danbee; Joo, Haejin; Ahn, Ginnae; Kim, Min Ju; Bing, So Jin; An, Subin; Kim, Hyunki; Kang, Kyung-goo; Lim, Yoon-Kyu; Jee, Youngheun

    2012-06-01

    Vanadium, an essential micronutrient, has been implicated in controlling diabetes and carcinogenesis and in impeding reactive oxygen species (ROS) generation. γ-ray irradiation triggers DNA damage by inducing ROS production and causes diminution in radiosensitive immunocytes. In this study, we elucidate the immune activation capacities of Jeju water containing vanadium on immunosuppression caused by γ-ray irradiation, and identify its mechanism using various low doses of NaVO(3). We examined the intracellular ROS generation, DNA damage, cell proliferation, population of splenocytes, and cytokine/antibody profiles in irradiated mice drinking Jeju water for 180 days and in non-irradiated and in irradiated splenocytes both of which were treated with NaVO(3). Both Jeju water and 0.245 μM NaVO(3) attenuated the intracellular ROS generation and DNA damage in splenocytes against γ-ray irradiation. Splenocytes were significantly proliferated by the long-term intake of Jeju water and by 0.245 μM NaVO(3) treatment, and the expansion of B cells accounted for the increased number of splenocytes. Also, 0.245 μM NaVO(3) treatment showed the potency to amplify the production of IFN-γ and total IgG in irradiated splenocytes, which correlated with the expansion of B cells. Collectively, Jeju water containing vanadium possesses the immune activation property against damages caused by γ-irradiation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. TLR9-ERK-mTOR signaling is critical for autophagic cell death induced by CpG oligodeoxynucleotide 107 combined with irradiation in glioma cells

    PubMed Central

    Li, Xiaoli; Cen, Yanyan; Cai, Yongqing; Liu, Tao; Liu, Huan; Cao, Guanqun; Liu, Dan; Li, Bin; Peng, Wei; Zou, Jintao; Pang, Xueli; Zheng, Jiang; Zhou, Hong

    2016-01-01

    Synthetic oligodeoxynucleotides containing unmethylated CpG dinucleotides (CpG ODN) function as potential radiosensitizers for glioma treatment, although the underlying mechanism is unclear. It was observed that CpG ODN107, when combined with irradiation, did not induce apoptosis. Herein, the effect of CpG ODN107 + irradiation on autophagy and the related signaling pathways was investigated. In vitro, CpG ODN107 + irradiation induced autophagosome formation, increased the ratio of LC3 II/LC3 I, beclin 1 and decreased p62 expression in U87 cells. Meanwhile, CpG ODN107 also increased LC3 II/LC3 I expression in U251 and CHG-5 cells. In vivo, CpG ODN107 combined with local radiotherapy induced autophagosome formation in orthotopic transplantation tumor. Investigation of the molecular mechanisms demonstrated that CpG ODN107 + irradiation increased the levels of TLR9 and p-ERK, and decreased the level of p-mTOR in glioma cells. Further, TLR9-specific siRNA could affect the expressions of p-ERK and autophagy-related proteins in glioma cells. Taken together, CpG ODN107 combined with irradiation could induce autophagic cell death, and this effect was closely related to the TLR9-ERK-mTOR signaling pathway in glioma cells, providing new insights into the investigation mechanism of CpG ODN. PMID:27251306

  3. Forced running exercise attenuates hippocampal neurogenesis impairment and the neurocognitive deficits induced by whole-brain irradiation via the BDNF-mediated pathway

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ji, Jian-feng; Ji, Sheng-jun; Sun, Rui

    Highlights: •Forced exercise can ameliorate WBI induced cognitive impairment in our rat model. •Mature BDNF plays an important role in the effects of forced exercise. •Exercise may be a possible treatment of the radiation-induced cognitive impairment. -- Abstract: Cranial radiotherapy induces progressive and debilitating cognitive deficits, particularly in long-term cancer survivors, which may in part be caused by the reduction of hippocampal neurogenesis. Previous studies suggested that voluntary exercise can reduce the cognitive impairment caused by radiation therapy. However, there is no study on the effect of forced wheel exercise and little is known about the molecular mechanisms mediating themore » effect of exercise. In the present study, we investigated whether the forced running exercise after irradiation had the protective effects of the radiation-induced cognitive impairment. Sixty-four Male Sprague–Dawley rats received a single dose of 20 Gy or sham whole-brain irradiation (WBI), behavioral test was evaluated using open field test and Morris water maze at 2 months after irradiation. Half of the rats accepted a 3-week forced running exercise before the behavior detection. Immunofluorescence was used to evaluate the changes in hippocampal neurogenesis and Western blotting was used to assess changes in the levels of mature brain-derived neurotrophic factor (BDNF), phosphorylated tyrosine receptor kinase B (TrkB) receptor, protein kinase B (Akt), extracellular signal-regulated kinase (ERK), calcium-calmodulin dependent kinase (CaMKII), cAMP-calcium response element binding protein (CREB) in the BDNF–pCREB signaling. We found forced running exercise significantly prevented radiation-induced cognitive deficits, ameliorated the impairment of hippocampal neurogenesis and attenuated the down-regulation of these proteins. Moreover, exercise also increased behavioral performance, hippocampal neurogenesis and elevated BDNF–pCREB signaling in non-irradiation

  4. Pressure control of a proton beam-irradiated water target through an internal flow channel-induced thermosyphon.

    PubMed

    Hong, Bong Hwan; Jung, In Su

    2017-07-01

    A water target was designed to enhance cooling efficiency using a thermosyphon, which is a system that uses natural convection to induce heat exchange. Two water targets were fabricated: a square target without any flow channel and a target with a flow channel design to induce a thermosyphon mechanism. These two targets had the same internal volume of 8 ml. First, visualization experiments were performed to observe the internal flow by natural convection. Subsequently, an experiment was conducted to compare the cooling performance of both water targets by measuring the temperature and pressure. A 30-MeV proton beam with a beam current of 20 μA was used to irradiate both targets. Consequently, the target with an internal flow channel had a lower mean temperature and a 50% pressure drop compared to the target without a flow channel during proton beam irradiation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. SIGN-R1 and complement factors are involved in the systemic clearance of radiation-induced apoptotic cells in whole-body irradiated mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, Jin-Yeon; Loh, SoHee; Cho, Eun-hee

    Although SIGN-R1-mediated complement activation pathway has been shown to enhance the systemic clearance of apoptotic cells, the role of SIGN-R1 in the clearance of radiation-induced apoptotic cells has not been characterized and was investigated in this study. Our data indicated that whole-body γ-irradiation of mice increased caspase-3{sup +} apoptotic lymphocyte numbers in secondary lymphoid organs. Following γ-irradiation, SIGN-R1 and complements (C4 and C3) were simultaneously increased only in the mice spleen tissue among the assessed tissues. In particular, C3 was exclusively activated in the spleen. The delayed clearance of apoptotic cells was markedly prevalent in the spleen and liver ofmore » SIGN-R1 KO mice, followed by a significant increase of CD11b{sup +} cells. These results indicate that SIGN-R1 and complement factors play an important role in the systemic clearance of radiation-induced apoptotic innate immune cells to maintain tissue homeostasis after γ-irradiation. - Highlights: • Splenic SIGN-R1{sup +} macrophages are activated after γ-irradiation. • C3 and C4 levels increased and C3 was activated in the spleen after γ-irradiation. • SIGN-R1 mediated the systemic clearance of radiation-induced apoptotic cells in spleen and liver.« less

  6. [Impact of heat waves on non-accidental deaths in Jinan, China].

    PubMed

    Zhang, J; Liu, S Q; Zhou, L; Gong, S P; Liu, Y L; Zhang, Y; Zhang, J

    2016-02-20

    To assess the impact of heat waves on non-accidental deaths, and to investigate the influencing factors for deaths caused by heat waves in Jinan, China. Daily death data and meteorological data for summer days with or without heat waves in Jinan from 2012 to 2014 were collected, and a cross-over analysis was conducted to evaluate the influence of heat waves on non-accidental deaths and deaths caused by other reasons. The univariate and multivariate logistic regression models were used to investigate the influencing factors for deaths caused by heat waves. The risks of non-accidental deaths and deaths caused by circulation system diseases during the days with heat waves were 1.82 times(95% CI: 1.47~2.36) and 1.53 times(95% CI: 1.14~2.07) those during the days without heat waves. The multivariate logistic regression analysis showed that old age(≥75 years)(OR=1.184, 95% CI: 1.068~1.313), low educational level(OR=1.187, 95% CI: 1.064~1.324), and deaths outside hospital(OR=1.105, 95% CI: 1.009~1.210) were associated with the high risk of deaths during the days with heat waves. Heat waves significantly increase the risk of non-accidental deaths and deaths caused by circulation system diseases in Jinan, and the deaths during the days with heat waves are related to age, educational level, and place of death.

  7. Distinct photoresponse in graphene induced by laser irradiation and interfacial gating.

    NASA Astrophysics Data System (ADS)

    Wang, Wenhui; Guo, Xitao; Nan, Haiyan; Ni, Zhenhua; Spectroscopy; Optoelectronics Group Team

    Graphene-based photodetectors have recently received much attention due to its unique optical and electronic properties. The photoresponse modulation plays a crucial role in the study of photocurrent generation mechanism and optoelectronic applications. Here, the tunable p-p +-p junctions of graphene were fabricated through simple laser irradiation process. Distinct photoresponse was observed at the graphene (G)-laser irradiation graphene (LIG) junction. Detailed investigation suggests that the photo-thermoelectric effect, instead of the photovoltaic effect, dominates the photocurrent generation at the G-LIG junction. On the other hand, the localized interface states, existing at the silicon dioxide/lightly doped Si interface, would induce an interfacial gating mechanism, which will enhance the photoresponsivity to 1000 A/W. More important, the photoresponse time of our device has been pushed to 400ns. The current device structure does not need a complicated fabrication process and is fully compatible with silicon technology. This work will open up a route to graphene-based high-performance optoelectronic devices. This work was supported by Southeast University.

  8. An alternative approach for computing seismic response with accidental eccentricity

    NASA Astrophysics Data System (ADS)

    Fan, Xuanhua; Yin, Jiacong; Sun, Shuli; Chen, Pu

    2014-09-01

    Accidental eccentricity is a non-standard assumption for seismic design of tall buildings. Taking it into consideration requires reanalysis of seismic resistance, which requires either time consuming computation of natural vibration of eccentric structures or finding a static displacement solution by applying an approximated equivalent torsional moment for each eccentric case. This study proposes an alternative modal response spectrum analysis (MRSA) approach to calculate seismic responses with accidental eccentricity. The proposed approach, called the Rayleigh Ritz Projection-MRSA (RRP-MRSA), is developed based on MRSA and two strategies: (a) a RRP method to obtain a fast calculation of approximate modes of eccentric structures; and (b) an approach to assemble mass matrices of eccentric structures. The efficiency of RRP-MRSA is tested via engineering examples and compared with the standard MRSA (ST-MRSA) and one approximate method, i.e., the equivalent torsional moment hybrid MRSA (ETM-MRSA). Numerical results show that RRP-MRSA not only achieves almost the same precision as ST-MRSA, and is much better than ETM-MRSA, but is also more economical. Thus, RRP-MRSA can be in place of current accidental eccentricity computations in seismic design.

  9. Irradiation-induced microchemical changes in highly irradiated 316 stainless steel

    NASA Astrophysics Data System (ADS)

    Fujii, K.; Fukuya, K.

    2016-02-01

    Cold-worked 316 stainless steel specimens irradiated to 74 dpa in a pressurized water reactor (PWR) were analyzed by atom probe tomography (APT) to extend knowledge of solute clusters and segregation at higher doses. The analyses confirmed that those clusters mainly enriched in Ni-Si or Ni-Si-Mn were formed at high number density. The clusters were divided into three types based on their size and Mn content; small Ni-Si clusters (3-4 nm in diameter), and large Ni-Si and Ni-Si-Mn clusters (8-10 nm in diameter). The total cluster number density was 7.7 × 1023 m-3. The fraction of large clusters was almost 1/10 of the total density. The average composition (in at%) for small clusters was: Fe, 54; Cr, 12; Mn, 1; Ni, 22; Si, 11; Mo, 1, and for large clusters it was: Fe, 44; Cr, 9; Mn, 2; Ni, 29; Si, 14; Mo,1. It was likely that some of the Ni-Si clusters correspond to γ‧ phase precipitates while the Ni-Si-Mn clusters were precursors of G phase precipitates. The APT analyses at grain boundaries confirmed enrichment of Ni, Si, P and Cu and depletion of Fe, Cr, Mo and Mn. The segregation behavior was consistent with previous knowledge of radiation induced segregation.

  10. Flagellin preconditioning enhances the efficacy of mesenchymal stem cells in an irradiation-induced proctitis model.

    PubMed

    Linard, Christine; Strup-Perrot, Carine; Lacave-Lapalun, Jean-Victor; Benderitter, Marc

    2016-09-01

    The success of mesenchymal stem cell transplantation for proctitis depends not only on cell donors but also on host microenvironmental factors, which play a major role in conditioning mesenchymal stem cell immunosuppressive action and repair. This study sought to determine if flagellin, a TLR5 ligand, can enhance the mesenchymal stem cell treatment efficacy in radiation-induced proctitis. With the use of a colorectal model of 27 Gy irradiation in rats, we investigated and compared the effects on immune capacity and remodeling at 28 d after irradiation of the following: 1) systemic mesenchymal stem cell (5 × 10(6)) administration at d 7 after irradiation, 2) administration of flagellin at d 3 and systemic mesenchymal stem cell administration at d 7, and 3) in vitro preconditioning of mesenchymal stem cells with flagellin, 24 h before their administration on d 7. The mucosal CD8(+) T cell population was normalized after treatment with flagellin-preconditioned mesenchymal stem cells or flagellin plus mesenchymal stem cells, whereas mesenchymal stem cells alone did not alter the radiation-induced elevation of CD8(+) T cell frequency. Mesenchymal stem cell treatment returned the irradiation-elevated frequency of CD25(+) cells in the mucosa-to-control levels, whereas both flagellin-preconditioned mesenchymal stem cell and flagellin-plus-mesenchymal stem cell treatment each significantly increased not only CD25(+) cell frequency but also forkhead box p3 and IL-2Rα expression. Specifically, IL-10 was overexpressed after flagellin-preconditioned mesenchymal stem cell treatment. Analysis of collagen expression showed that the collagen type 1/collagen type 3 ratio, an indicator of wound-healing maturation, was low in the irradiated and mesenchymal stem cell-treated groups and returned to the normal level only after the flagellin-preconditioned mesenchymal stem cell treatment. This was associated with a reduction in myofibroblast accumulation. In a proctitis model, flagellin

  11. Experience with intubated patients does not affect the accidental extubation rate in pediatric intensive care units and intensive care nurseries.

    PubMed

    Frank, B S; Lewis, R J

    1997-06-01

    Accidental extubation is a potentially serious event for pediatric or neonatal patients with respiratory failure, especially in clinical settings in which personnel capable of performing reintubation may not be readily available. Thus the rate of accidental extubation in small intensive care units that operate without 24-hour in-house physician availability may be an important quality assurance indicator. The objective of this study were to determine the accidental extubation rate at a single small pediatric intensive care unit (PICU) and compare it with published reports. This study was carried out in a six-bed PICU at Washoe Medical Center in Reno, Nevada, with a relatively low level of patient acuity, as measured by PRISM score and the frequency of intubation, and without 24-hour in-house physician availability. All intubated patients admitted during the 5-year period from January 1, 1989 to December 31, 1993 were included. The primary outcome measure was the occurrence of accidental extubation. We observed only two accidental extubations in 1,749 intubated-patient-days (IPD) (0.114 accidental extubations/100 IPD [95% confidence interval 0.014-0.413 accidental extubations/ 100 IPD]). This rate of accidental extubation was compared with data in published reports from neonatal intensive care units (NICUs) and PICUs, which ranged from 0.14 accidental extubations/100 IPD to 4.36 accidental extubations/100 IPD. The dependence of the observed accidental extubation rate on unit size and institutional experience with intubated patients, as measured by the average number of intubated patients, was examined. We found no evidence that the accidental extubation rate is higher in smaller units or units with less institutional experience. Low rates can be achieved in small units with low acuity.

  12. Accidental Kähler moduli inflation

    NASA Astrophysics Data System (ADS)

    Maharana, Anshuman; Rummel, Markus; Sumitomo, Yoske

    2015-09-01

    We study a model of accidental inflation in type IIB string theory where inflation occurs near the inflection point of a small Kähler modulus. A racetrack structure helps to alleviate the known concern that string-loop corrections may spoil Kähler Moduli Inflation unless having a significant suppression via the string coupling or a special brane setup. Also, the hierarchy of gauge group ranks required for the separation between moduli stabilization and inflationary dynamics is relaxed. The relaxation becomes more significant when we use the recently proposed D-term generated racetrack model.

  13. Nanoindentation of ion-irradiated reactor pressure vessel steels - model-based interpretation and comparison with neutron irradiation

    NASA Astrophysics Data System (ADS)

    Röder, F.; Heintze, C.; Pecko, S.; Akhmadaliev, S.; Bergner, F.; Ulbricht, A.; Altstadt, E.

    2018-04-01

    Ion-irradiation-induced hardening is investigated on six selected reactor pressure vessel (RPV) steels. The steels were irradiated with 5 MeV Fe2+ ions at fluences ranging from 0.01 to 1.0 displacements per atom (dpa) and the induced hardening of the surface layer was probed with nanoindentation. To separate the indentation size effect and the substrate effect from the irradiation-induced hardness profile, we developed an analytic model with the plastic zone of the indentation approximated as a half sphere. This model allows the actual hardness profile to be retrieved and the measured hardness increase to be assigned to the respective fluence. The obtained values of hardness increase vs. fluence are compared for selected pairs of samples in order to extract effects of the RPV steel composition. We identify hardening effects due to increased levels of copper, manganese-nickel and phosphorous. Further comparison with available neutron-irradiated conditions of the same heats of RPV steels indicates pronounced differences of the considered effects of composition for irradiation with neutrons vs. ions.

  14. Patterns of accidental deaths in Kuwait: a retrospective descriptive study from 2003-2009.

    PubMed

    Al-Kandary, Nadia; Al-Waheeb, Salah

    2015-03-28

    Accidents are a preventable cause of death. Unfortunately it accounts for a large number of deaths in many societies. In Kuwait, road traffic accidents (RTA) is the leading cause of death in young people. The study investigated the patterns of accidental deaths in Kuwait, one of the Gulf States which incorporates a wide variety of multi-ethnic communities. The study was retrospective from 2003-2009. Data of forensic cases were collected from the general department of criminal evidence (GDCE) in the ministry of interior (MOI).We attempted to find out causes of accidental death and the prevelance of each cause. Furthermore, the relationship of demographic factors (eg. Age, sex, marital status and nationality) with each cause of accidental death in Kuwait were studied. The material of this study constituted a total of 4886 reported accidental deaths referred for Medico-legal examination. Road traffic accidents was by far the most prevalent cause of death (64.6%) followed by fall from height (13.1%). Poisoning and mine explosions were amongst the least common causes. The government of Kuwait needs to take strong measures to promote safety in the workplace and households by educational campaigns.

  15. Irradiation Microstructure of Austenitic Steels and Cast Steels Irradiated in the BOR-60 Reactor at 320°C

    NASA Astrophysics Data System (ADS)

    Yang, Yong; Chen, Yiren; Huang, Yina; Allen, Todd; Rao, Appajosula

    Reactor internal components are subjected to neutron irradiation in light water reactors, and with the aging of nuclear power plants around the world, irradiation-induced material degradations are of concern for reactor internals. Irradiation-induced defects resulting from displacement damage are critical for understanding degradation in structural materials. In the present work, microstructural changes due to irradiation in austenitic stainless steels and cast steels were characterized using transmission electron microscopy. The specimens were irradiated in the BOR-60 reactor, a fast breeder reactor, up to 40 dpa at 320°C. The dose rate was approximately 9.4x10-7 dpa/s. Void swelling and irradiation defects were analyzed for these specimens. A high density of faulted loops dominated the irradiated-altered microstructures. Along with previous TEM results, a dose dependence of the defect structure was established at 320°C.

  16. Atom redistribution and multilayer structure in NiTi shape memory alloy induced by high energy proton irradiation

    NASA Astrophysics Data System (ADS)

    Wang, Haizhen; Yi, Xiaoyang; Zhu, Yingying; Yin, Yongkui; Gao, Yuan; Cai, Wei; Gao, Zhiyong

    2017-10-01

    The element distribution and surface microstructure in NiTi shape memory alloys exposed to 3 MeV proton irradiation were investigated. Redistribution of the alloying element and a clearly visible multilayer structure consisting of three layers were observed on the surface of NiTi shape memory alloys after proton irradiation. The outermost layer consists primarily of a columnar-like TiH2 phase with a tetragonal structure, and the internal layer is primarily comprised of a bcc austenite phase. In addition, the Ti2Ni phase, with an fcc structure, serves as the transition layer between the outermost and internal layer. The above-mentioned phenomenon is attributed to the preferential sputtering of high energy protons and segregation induced by irradiation.

  17. Osborn waves in severe accidental hypothermia secondary to prolonged immobilization and malnutrition.

    PubMed

    Rotondi, Francesco; Manganelli, Fiore; Candelmo, Fiore; Marino, Luciano; Di Lorenzo, Emilio; Alfano, Ferdinando; Stanco, Giovanni; Rosato, Giuseppe

    2010-07-01

    We report the case of a 77-year-old man, in whom accidental hypothermia was secondary to prolonged immobilization and malnutrition. The electrocardiogram showed typical Osborn waves, which disappeared with the rewarming of the patient. The diagnosis of hypothermia is easy in patients with a history of prolonged exposure to a cold environment but accidental hypothermia may also occur as a consequence of prolonged immobilization and malnutrition. ECG analysis is very important for a correct and fast diagnosis.

  18. Electron beam irradiation induced compatibilization of immiscible polyethylene/ethylene vinyl acetate (PE/EVA) blends: Mechanical properties and morphology stability

    NASA Astrophysics Data System (ADS)

    Entezam, Mehdi; Aghjeh, Mir Karim Razavi; Ghaffari, Mehdi

    2017-02-01

    Gel content, mechanical properties and morphology of immiscible PE/EVA blends irradiated by high energy electron beam were studied. The results of gel content measurements showed that the capability of cross-linking of the blend samples increased with an increase of the EVA composition. Also, the gel content for most compositions of the blends displayed a positive deviation from the additive rule. The results of mechanical properties showed that the tensile strength and elongation at break of the samples increased and decreased, respectively, with irradiation dose. On the other hand, the mechanical properties of the irradiated blends also depicted a positive deviation from additive rule contrary to the un-irradiated blends. A synergistic effect observed for the mechanical properties improvement of the irradiated blends and it was attributed to the probable formation of the PE-graft-EVA copolymers at the interface of the blends during the irradiation process. A theoretical analysis revealed that irradiation induced synergistic effect was more significant for EVA-rich blends with weaker interfacial interaction as compared to PE-rich blends. The morphological analysis indicated that the blend morphology was not affected obviously, whereas it was stabilized by irradiation.

  19. The fate of mitochondrial loci in rho minus mutants induced by ultraviolet irradiation of Saccharomyces cerevisiae: effects of different post-irradiation treatments.

    PubMed

    Heude, M; Moustacchi, E

    1979-09-01

    Three main features regarding the loss of mitochondrial genetic markers among rho- mutants induced by ultraviolet irradiation are reported: (a) the frequency of loss of six loci examined increases with UV dose; (b) preferential loss of one region of the mitochondrial genome observed in spontaneous rho- mutants is enhanced by UV; and (c) the loss of each marker results from large deletions. Marker loss in rho- mutants was also investigated under conditions that modulate rho- induction. Liquid holding of irradiated exponential or stationary phase cells, as well as a split-dose regime applied to stationary phase cells, results in rho- mutants in which the loss of markers is correlated with rho- induction: the more sensitive the cells are to rho- induction, the more frequent are the marker losses among rho- clones derived from these cells. This correlation is not found in exponential-phase cells submitted to a split-dose treatment, suggesting that a different mechanism is involved in the latter case. It is known that UV-induced pyrimidine dimers are not excised in a controlled manner in mitochondrial DNA. However, our studies indicate that an accurate repair mechanism (of the recombinational type ?) can lead to the restoration of mitochondrial genetic information in growing cells.

  20. Effect of Pre-Irradiation Annealing and Laser Modification on the Formation of Radiation-Induced Surface Color Centers in Lithium Fluoride

    NASA Astrophysics Data System (ADS)

    Voitovich, A. P.; Kalinov, V. S.; Novikov, A. N.; Radkevich, A. V.; Runets, L. P.; Stupak, A. P.; Tarasenko, N. V.

    2017-01-01

    It is shown that surface color centers of the same type are formed in the surface layer and in regions with damaged crystal structure inside crystalline lithium fluoride after γ-irradiation. Results are presented from a study of the effect of pre-irradiation annealing on the efficiency with which surface centers are formed in lithium fluoride nanocrystals. Raising the temperature for pre-irradiation annealing from room temperature to 250°C leads to a substantial reduction in the efficiency with which these centers are created. Surface color centers are not detected after γ-irradiation for pre-irradiation annealing temperatures of 300°C and above. Adsorption of atmospheric gases on the crystal surface cannot be regarded as a necessary condition for the formation of radiation-induced surface centers.

  1. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Prevention of accidental ignition. 192.751 Section 192.751 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE:...

  2. Gap structure in Fe-based superconductors with accidental nodes: The role of hybridization

    NASA Astrophysics Data System (ADS)

    Hinojosa, Alberto; Chubukov, Andrey V.

    2015-06-01

    We study the effects of hybridization between the two electron pockets in Fe-based superconductors with s -wave gap with accidental nodes. We argue that hybridization reconstructs the Fermi surfaces and also induces an additional interpocket pairing component. We analyze how these two effects modify the gap structure by tracing the position of the nodal points of the energy dispersions in the superconducting state. We find three possible outcomes. In the first, the nodes simply shift their positions in the Brillouin zone; in the second, the nodes merge and disappear, in which case the gap function has either equal or opposite signs on the electron pockets; in the third, a new set of nodal points emerges, doubling the original number of nodes.

  3. UVB-irradiated keratinocytes induce melanoma-associated ganglioside GD3 synthase gene in melanocytes via secretion of tumor necrosis factor α and interleukin 6

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miyata, Maiko; Department of Biochemistry II, Nagoya University Graduate School of Medicine, 65 Tsurumai, Showa-ku, Nagoya 466-0065; Ichihara, Masatoshi

    Highlights: • Melanocytes showed low ST8SIA1 and high B3GALT4 levels in contrast with melanomas. • Direct UVB irradiation of melanocytes did not induce ganglioside synthase genes. • Culture supernatants of UVB-irradiated keratinocytes induced ST8SIA1 in melanocytes. • TNFα and IL-6 secreted from keratinocytes enhanced ST8SIA1 expression in melanocytes. • Inflammatory cytokines induced melanoma-related ST8SIA1 in melanocytes. - Abstract: Although expression of gangliosides and their synthetic enzyme genes in malignant melanomas has been well studied, that in normal melanocytes has been scarcely analyzed. In particular, changes in expression levels of glycosyltransferase genes responsible for ganglioside synthesis during evolution of melanomas frommore » melanocytes are very important to understand roles of gangliosides in melanomas. Here, expression of glycosyltransferase genes related to the ganglioside synthesis was analyzed using RNAs from cultured melanocytes and melanoma cell lines. Quantitative RT-PCR revealed that melanomas expressed high levels of mRNA of GD3 synthase and GM2/GD2 synthase genes and low levels of GM1/GD1b synthase genes compared with melanocytes. As a representative exogenous stimulation, effects of ultraviolet B (UVB) on the expression levels of 3 major ganglioside synthase genes in melanocytes were analyzed. Although direct UVB irradiation of melanocytes caused no marked changes, culture supernatants of UVB-irradiated keratinocytes (HaCaT cells) induced definite up-regulation of GD3 synthase and GM2/GD2 synthase genes. Detailed examination of the supernatants revealed that inflammatory cytokines such as TNFα and IL-6 enhanced GD3 synthase gene expression. These results suggest that inflammatory cytokines secreted from UVB-irradiated keratinocytes induced melanoma-associated ganglioside synthase genes, proposing roles of skin microenvironment in the promotion of melanoma-like ganglioside profiles in melanocytes.« less

  4. Effects of compositional complexity on the ion-irradiation induced swelling and hardening in Ni-containing equiatomic alloys

    DOE PAGES

    Jin, K.; Lu, C.; Wang, L. M.; ...

    2016-04-14

    The impact of compositional complexity on the ion-irradiation induced swelling and hardening is studied in Ni and six Ni-containing equiatomic alloys with face-centered cubic structure. The irradiation resistance at the temperature of 500 °C is improved by controlling the number and, especially, the type of alloying elements. Alloying with Fe and Mn has a stronger influence on swelling reduction than does alloying with Co and Cr. Lastly, the quinary alloy NiCoFeCrMn, with known excellent mechanical properties, has shown 40 times higher swelling tolerance than nickel.

  5. Sulforaphane mitigates genotoxicity induced by radiation and anticancer drugs in human lymphocytes.

    PubMed

    Katoch, Omika; Kumar, Arun; Adhikari, Jawahar S; Dwarakanath, Bilikere S; Agrawala, Paban K

    2013-12-12

    Sulforaphane, present in cruciferous vegetables such as broccoli, is a dietary anticancer agent. Sulforaphane, added 2 or 20 h following phytohemaglutinin stimulation to cultured peripheral blood lymphocytes of individuals accidentally exposed to mixed γ and β-radiation, reduced the micronucleus frequency by up to 70%. Studies with whole blood cultures obtained from healthy volunteers confirmed the ability of sulforaphane to ameliorate γ-radiation-induced genotoxicity and to reduce micronucleus induction by other DNA-damaging anticancer agents, such as bleomycin and doxorubicin. This reduction in genotoxicity in lymphocytes treated at the G(0) or G(1) stage suggests a role for sulforaphane in modulating DNA repair. Sulforaphane also countered the radiation-induced increase in lymphocyte HDAC activity, to control levels, when cells were treated 2 h after exposure, and enhanced histone H4 acetylation status. Sulforaphane post-irradiation treatment enhanced the CD 34(+)Lin(-) cell population in culture. Sulforaphane has therapeutic potential for management of the late effects of radiation. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Respiration Induced Heart Motion and Indications of Gated Delivery for Left-Sided Breast Irradiation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Qi, X. Sharon, E-mail: xiangrong.qi@ucdenver.edu; Hu, Angela; Wang Kai

    Purpose: To investigate respiration-induced heart motion for left-sided breast irradiation using a four-dimensional computed tomography (4DCT) technique and to determine novel indications to assess heart motion and identify breast patients who may benefit from a gated treatment. Methods and Materials: Images of 4DCT acquired during free breathing for 20 left-sided breast cancer patients, who underwent whole breast irradiation with or without regional nodal irradiation, were analyzed retrospectively. Dose distributions were reconstructed in the phases of 0%, 20%, and 50%. The intrafractional heart displacement was measured in three selected transverse CT slices using D{sub LAD} (the distance from left ascending aortamore » to a fixed line [connecting middle point of sternum and the body] drawn on each slice) and maximum heart depth (MHD, the distance of the forefront of the heart to the line). Linear regression analysis was used to correlate these indices with mean heart dose and heart dose volume at different breathing phases. Results: Respiration-induced heart displacement resulted in observable variations in dose delivered to the heart. During a normal free-breathing cycle, heart-induced motion D{sub LAD} and MHD changed up to 9 and 11 mm respectively, resulting in up to 38% and 39% increases of mean doses and V{sub 25.2} for the heart. MHD and D{sub LAD} were positively correlated with mean heart dose and heart dose volume. Respiratory-adapted gated treatment may better spare heart and ipsilateral-lung compared with the conventional non-gated plan in a subset of patients with large D{sub LAD} or MHD variations. Conclusion: Proposed indices offer novel assessment of heart displacement based on 4DCT images. MHD and D{sub LAD} can be used independently or jointly as selection criteria for respiratory gating procedure before treatment planning. Patients with great intrafractional MHD variations or tumor(s) close to the diaphragm may particularly benefit from the

  7. Surface and structure modification induced by high energy and highly charged uranium ion irradiation in monocrystal spinel

    NASA Astrophysics Data System (ADS)

    Yang, Yitao; Zhang, Chonghong; Song, Yin; Gou, Jie; Zhang, Liqing; Meng, Yancheng; Zhang, Hengqing; Ma, Yizhun

    2014-05-01

    Due to its high temperature properties and relatively good behavior under irradiation, magnesium aluminate spinel (MgAl2O4) is considered as a possible material to be used as inert matrix for the minor actinides burning. In this case, irradiation damage is an unavoidable problem. In this study, high energy and highly charged uranium ions (290 MeV U32+) were used to irradiate monocrystal spinel to the fluence of 1.0 × 1013 ions/cm2 to study the modification of surface and structure. Highly charged ions carry large potential energy, when they interact with a surface, the release of potential energy results in the modification of surface. Atomic force microscopy (AFM) results showed the occurrence of etching on surface after uranium ion irradiation. The etching depth reached 540 nm. The surprising efficiency of etching is considered to be induced by the deposition of potential energy with high density. The X-ray diffraction results showed that the (4 4 0) diffraction peak obviously broadened after irradiation, which indicated that the distortion of lattice has occurred. After multi-peak Gaussian fitting, four Gaussian peaks were separated, which implied that a structure with different damage layers could be formed after irradiation.

  8. Thermal effects in tissues induced by interstitial irradiation of near infrared laser with a cylindrical diffuser

    NASA Astrophysics Data System (ADS)

    Le, Kelvin; Johsi, Chet; Figueroa, Daniel; Goddard, Jessica; Li, Xiaosong; Towner, Rheal A.; Saunders, Debra; Smith, Nataliya; Liu, Hong; Hode, Tomas; Nordquist, Robert E.; Chen, Wei R.

    2011-03-01

    Laser immunotherapy (LIT), using non-invasive laser irradiation, has resulted in promising outcomes in the treatment of late-stage cancer patients. However, the tissue absorption of laser light limits the clinical applications of LIT in patients with dark skin, or with deep tumors. The present study is designed to investigate the thermal effects of interstitial irradiation using an 805-nm laser with a cylindrical diffuser, in order to overcome the limitations of the non-invasive mode of treatment. Cow liver and rat tumors were irradiated using interstitial fiber. The temperature increase was monitored by thermocouples that were inserted into the tissue at different sites around the cylinder fiber. Three-dimensional temperature distribution in target tissues during and after interstitial laser irradiation was also determined by Proton Resonance Frequency. The preliminary results showed that the output power of laser and the optical parameters of the target tissue determined the light distribution in the tissue. The temperature distributions varied in the tissue according to the locations relative to the active tip of the cylindrical diffuser. The temperature increase is strongly related to the laser power and irradiation time. Our results using thermocouples and optical sensors indicated that the PRF method is reliable and accurate for temperature determination. Although the inhomogeneous biological tissues could result in temperature fluctuation, the temperature trend still can be reliable enough for the guidance of interstitial irradiation. While this study provides temperature profiles in tumor tissue during interstitial irradiation, the biological effects of the irradiation remain unclear. Future studies will be needed, particularly in combination with the application of immunostimulant for inducing tumor-specific immune responses in the treatment of metastatic tumors.

  9. Ameliorative effect of black grape juice on systemic alterations and mandibular osteoradionecrosis induced by whole brain irradiation in rats.

    PubMed

    Freitas, Robson B; González, Paquita; Martins, Nara Maria B; Andrade, Edson R; Cesteros Morante, María Jesús; Conles Picos, Iban; Costilla García, Serafín; Bauermann, Liliane F; Barrio, Juan Pablo

    2017-02-01

    Whole brain irradiation (WBI) causes a variety of secondary side-effects including anorexia and bone necrosis. We evaluated the radiomodifying effect of black grape juice (BGJ) on WBI alterations in rats measuring food and water intake, body weight, hemogram, and morphological and histological mandibular parameters. Forty male rats (200-250 g) were exposed to eight sessions of cranial X-ray irradiation. The total dose absorbed was 32 Gy delivered over 2 weeks. Four groups were defined: (i) NG: non-irradiated, glucose and fructose solution-supplemented (GFS); (ii) NJ: non-irradiated, BGJ-supplemented; (iii) RG: irradiated, GFS-supplemented; and (iv) RJ: irradiated, BGJ-supplemented. Rats received daily BGJ or GFS dosing by gavage starting 4 days before, continuing during, and ending 4 days after WBI. RJ rats ingested more food and water and showed less body weight loss than RG rats during the irradiation period. Forty days after WBI, irradiated animals started losing weight again compared with controls as a consequence of masticatory hypofunction by mandibular osteoradionecrosis (ORN). Osteoclastic activity and inflammation were apparent in RG rat mandibles. BGJ was able to attenuate the severity of ORN as well as to improve white and red blood cell counts. Fractionated whole brain irradiation induces mandibular changes that interfere with normal feeding. BGJ can be used to mitigate systemic side-effects of brain irradiation and ORN.

  10. Suicide and accidental deaths in children and adolescents in England and Wales, 2001-2010.

    PubMed

    Windfuhr, Kirsten; While, David; Hunt, Isabelle M; Shaw, Jenny; Appleby, Louis; Kapur, Nav

    2013-12-01

    To investigate the impact of narrative verdicts on suicide statistics among 10-19-year-olds; to identify the number and rate of suicide and accidental deaths, particularly in 10-14-year-olds. National cohort study. England and Wales. Mid-year population estimates from the Office for National Statistics (ONS) were used to calculate rates per 100,000 population for suicide (undetermined and suicide verdicts) and accidental deaths (poisoning, hanging) for those aged 10-14 and 15-19. Trends in rates over time (2001-2010) were investigated using Poisson regression. Interaction tests were carried out to determine differences in trends between the two time periods (2001-2005 and 2006-2010). There were 1523 suicides (2.25/100,000). Suicide rates were highest in those aged 15-19 years (4.04/100,000) and in males (3.14/100,000). Between 2001 and 2010, rates significantly decreased among those aged 15-19 years (incidence rate-ratio (IRR): 0.95; 95% CI 0.93 to 0.97), with no change in rates of accidental deaths (IRR: 1.01, 95% CI 0.95 to 1.07). However, there was a significant interaction between the two time periods for accidental poisonings (2001-2005: IRR: 0.79 (95% CI 0.69 to 0.91); 2006-2010: IRR: 1.01 (95% CI 0.89 to 1.15), interaction p=0.012) and accidental hangings (2001-2005: IRR: 0.93 (95% CI 0.76 to 1.14); 2006-2010: IRR: 1.25 (95% CI 1.04 to 1.49), interaction=0.01) Undetermined deaths significantly decreased among females aged 15-19 yeras (IRR: 0.93; 95% CI 0.88 to 0.98). There were no significant trends among 10-14-year-olds. Rates of suicide are higher among older adolescents and males. There was a significant fall in suicide rates in males aged 15-19 years that was not accounted for by changes in rates of accidental death. The absence of a significant trend in suicide or accidental deaths in those aged 10-14 years may have been the result of small numbers. However, monitoring should continue to identify longitudinal trends in all young people.

  11. Prevention of accidental exposure in radiotherapy: the risk matrix approach.

    PubMed

    Vilaragut, J J; Duménigo, C; Delgado, J M; Morales, J; McDonnell, J D; Ferro, R; Ortiz López, P; Ramírez, M L; Pérez Mulas, A; Papadopulos, S; Gonçalves, M; López Morones, R; Sánchez Cayuela, C; Cascajo Castresana, A; Somoano, F; Álvarez, C; Guillén, A; Rodríguez, M; Pereira, P P; Nader, A

    2013-02-01

    Knowledge and lessons from past accidental exposures in radiotherapy are very helpful in finding safety provisions to prevent recurrence. Disseminating lessons is necessary but not sufficient. There may be additional latent risks for other accidental exposures, which have not been reported or have not occurred, but are possible and may occur in the future if not identified, analyzed, and prevented by safety provisions. Proactive methods are available for anticipating and quantifying risk from potential event sequences. In this work, proactive methods, successfully used in industry, have been adapted and used in radiotherapy. Risk matrix is a tool that can be used in individual hospitals to classify event sequences in levels of risk. As with any anticipative method, the risk matrix involves a systematic search for potential risks; that is, any situation that can cause an accidental exposure. The method contributes new insights: The application of the risk matrix approach has identified that another group of less catastrophic but still severe single-patient events may have a higher probability, resulting in higher risk. The use of the risk matrix approach for safety assessment in individual hospitals would provide an opportunity for self-evaluation and managing the safety measures that are most suitable to the hospital's own conditions.

  12. Detection of some irradiated spices on the basis of radiation induced damage of starch

    NASA Astrophysics Data System (ADS)

    Farkas, J.; Sharif, M. M.; Koncz, Á.

    Untreated and irradiated samples of spices were suspended in water, alkalized, and after heat-gelatinization, the apparent viscosity was determined by a rotational viscometer. Several spices, i.e. white pepper, black pepper, nutmeg and ginger showed considerable loss of viscosity as a function of γ-radiation dose in the dose range required for microbial decontamination of natural spices. Less promising results were obtained with spices such as allspice, garlic powder, and onion powder forming low-viscosity heat-treated suspensions even when unirradiated viscometric studies were also performed with a number of pepper samples of various origin to estimate the "natural" variation of rheological properties. Irradiation and storage studies were performed with ground black pepper samples of moisture contents in equilibrium with air of 25%, 50% and 75% R.H., respectively, either untreated or irradiated with 4, 8, 16 or 32 kGy, to study the effect of equilibrium relative humidity and storage time on detectability of radiation treatment. During the entire storage period of 100 days, statistically significant differences of the apparent viscosities of heat-gelatinized suspensions remained detectable between untreated samples and those irradiated with 8 kGy or higher doses. The apparent viscosity of high-moisture (75% E.R.H.) untreated samples was decreasing during long-term storage. Differences between viscosities of untreated and irradiated samples were enlarged when measured at elevated temperatures such as 50°C in the rotational viscometer, or in the boiling-water bath of a falling number apparatus. Other analytical indices such as onset and peak temperatures of gelatinization endotherms by DSC (damaged starch content), by colorimetry, reducing sugar content, alcohol-induced turbidity of hot water extracts of pepper samples, have been changed less dramatically by irradiation than the apparent viscosity of the gelatinized suspensions

  13. Accidental Chlorine Gas Intoxication: Evaluation of 39 Patients

    PubMed Central

    Sever, Mustafa; Mordeniz, Cengiz; Sever, Fidan; Dokur, Mehmet

    2009-01-01

    Background Chlorine is a known pulmonary irritant gas that may cause acute damage in the respiratory system. In this paper, the socio-demographic and clinical characteristics of 39 accidentally exposed patients to chlorine gas are reported and different emergency treatment modalities are also discussed. Methods Two emergency departments applications were retrospectively analyzed for evaluation of accidental chlorine gas exposure for year 2007. Patients were classified into 3 groups according to severity of clinical and laboratory findings based on the literature and duration of land of stay in the emergency department. The first group was slightly exposed (discharged within 6 hours), second group moderately exposed (treated and observed for 24 hours), and third group was severely exposed (hospitalized). Most of the patients were initially treated with a combination of humidified oxygen, corticosteroids, and bronchodilators. Results The average age was 17.03 ± 16.01 years (95% CI). Seven (17.9%) of them were female and 29 (74.4%) were children. Twenty-four patients (61.5%) were included in the first, nine (23.1%) were in second and six (15.4%) were in the third group. The presenting symptoms were cough, nausea, and vomiting and conjunctiva hyperemia for the first group, first groups symptoms plus dyspnea for the second group. Second groups symptoms plus palpitation, weakness and chest tightness were for the third group. Cough and dyspnea were seen in 64.1% and 30.8% of the patients respectively. No patients died. Conclusions The authors recommend that non symptomatic or slightly exposed patients do not need any specific treatment or symptomatic treatment is sufficient. Keywords Accidental; Chlorine exposure; Chlorine gas; Chlorine intoxication; Emergency department PMID:22481989

  14. [The hormonal and genetic effects induced by an irradiation in small dozes at Tradescantia (a clone 02)].

    PubMed

    Khomichenko, A A; Skorobogatova, I V; Karsunkina, N P; Zaĭnullin, V G

    2007-01-01

    The purpose of the present work was studying the possible interrelation of the hormonal status of plants and size of the genetic effects induced by an irradiation in small dozes. The frequency of somatic mutations in strings Tradescantia (a clone 02) at an irradiation in dozes up to 28 cGy was estimated. Influence radiations in a range from background up to 28 cGy on the maintenance in inflorescences Tradescantia (a clone 02) the basic groups of plant hormones is investigated: abscisic acid, cytokinin, auxin and gibberellin A3. It is shown, that small dozes of an irradiation cause extremely radical changes of hormonal balance in fabrics of inflorescences Tradescantia. Received results are discussed with attraction of the data on influence phytohormones on kinetics a cellular cycle.

  15. Electrical potentials in bone induced by ultrasound irradiation in the megahertz range

    NASA Astrophysics Data System (ADS)

    Okino, M.; Coutelou, S.; Mizuno, K.; Yanagitani, T.; Matsukawa, M.

    2013-09-01

    Low frequency mechanical studies have reported the contribution of stress-induced electrical potentials to bone metabolism. However, the healing mechanism of bone fractures by low intensity ultrasound is not yet clear. We demonstrate that bone can generate electrical potentials by ultrasound irradiation in the MHz range. Electrical potentials were obtained from the output of bovine cortical bone transducers. In the range of 0.7-2.5 MHz, sensitivities of bone transducers were around 1/1000 of a poly (vinylidene fluoride) ultrasonic transducer and did not depend on magnitude and alignment of hydroxyapatite crystallites in bone.

  16. DART model for irradiation-induced swelling of uranium silicide dispersion fuel elements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rest, J.; Hofman, G.L.

    1999-04-01

    Models for the interaction of uranium silicide dispersion fuels with an aluminum matrix, for the resultant reaction product swelling, and for the calculation of the stress gradient within the fuel particles are described within the context of DART fission-gas-induced swelling models. The effects of an aluminide shell on fuel particle swelling are evaluated. Validation of the model is demonstrated by comparing DART calculations with irradiation data for the swelling of U{sub 3}SiAl-Al and U{sub 3}Si{sub 2}-Al in variously designed dispersion fuel elements.

  17. Accidental poisoning with autumn crocus.

    PubMed

    Gabrscek, Lucija; Lesnicar, Gorazd; Krivec, Bojan; Voga, Gorazd; Sibanc, Branko; Blatnik, Janja; Jagodic, Boris

    2004-01-01

    We describe a case of a 43-yr-old female with severe multiorgan injury after accidental poisoning with Colchicum autumnale, which was mistaken for wild garlic (Allium ursinum). Both plants grow on damp meadows and can be confused in the spring when both plants have leaves but no blossoms. The autumn crocus contains colchicine, which inhibits cellular division. Treatment consisted of supportive care, antibiotic therapy, and granulocyte-directed growth factor. The patient was discharged from the hospital after three weeks. Three years after recovery from the acute poisoning, the patient continued to complain of muscle weakness and intermittent episodes of hair loss.

  18. Duration of time on shift before accidental blood or body fluid exposure for housestaff, nurses, and technicians.

    PubMed

    Green-McKenzie, Judith; Shofer, Frances S

    2007-01-01

    Shift work has been found to be associated with an increased rate of errors and accidents among healthcare workers (HCWs), but the effect of shift work on accidental blood and body fluid exposure sustained by HCWs has not been well characterized. To determine the duration of time on shift before accidental blood and body fluid exposure in housestaff, nurses, and technicians and the proportion of housestaff who sustain a blood and body fluid exposure after 12 hours on duty. This retrospective, descriptive study was conducted during a 24-month period at a large urban teaching hospital. Participants were HCWs who sustained an accidental blood and body fluid exposure. Housestaff were on duty significantly longer than both nursing staff (P=.02) and technicians (P<.0001) before accidental blood and body fluid exposure. Half of the blood and body fluid exposures sustained by housestaff occurred after being on duty 8 hours or more, and 24% were sustained after being on duty 12 hours or more. Of all HCWs, 3% reported an accidental blood and body fluid exposure, with specific rates of 7.9% among nurses, 9.4% among housestaff, and 3% among phlebotomists. Housestaff were significantly more likely to have longer duration of time on shift before blood and body fluid exposure than were the other groups. Almost one-quarter of accidental blood and body fluid exposures to housestaff were incurred after they had been on duty for 12 hours or more. Housestaff sustained a higher rate of accidental blood and body fluid exposures than did nursing staff and technicians.

  19. A prospective cohort study of non-fatal accidental overdose among street youth: the link with suicidal ideation.

    PubMed

    Richer, Isabelle; Bertrand, Karine; Vandermeerschen, Jill; Roy, Elise

    2013-07-01

    Drug overdose and suicide are the two leading causes of death among street youth. The literature discusses the two faces of drug overdose: accidental act and suicide attempt. Some authors have stated that accidental overdoses may be a hidden expression of suicidal ideation. This study longitudinally examined the relationship between recent suicidal ideations and non-fatal accidental drug overdoses among street youth. Between July 2001 and December 2005, 858 street youth (14-23 years old) were recruited for a prospective cohort study. Youth were eligible if, in the previous year, they had been without a place to sleep more than once or had used the services of street youth agencies on a regular basis (≥3). Participants completed baseline questionnaires and follow-up interviews were carried out every 6 months. Mixed-effect logistic regression models were conducted. Apart from suicidal ideation and accidental drug overdose, variables considered in the model were age, sex, problematic alcohol use, homelessness, injection drug use and polydrug use (≥3 drugs). Accidental drug overdose was significantly associated with suicidal ideation (adjusted odds ratio 1.88; 95% confidence interval 1.23-2.54). Homelessness, injection drug use and polydrug use were also significant in the final model. Results show that, during follow up, suicidal ideation independently increased risks of accidental overdose. They also underscore the need for interventions beyond educational prevention. Primary care practitioners should investigate suicidal ideations and behaviours of street youth in treatment for accidental overdose. © 2012 Australasian Professional Society on Alcohol and other Drugs.

  20. Hepatoprotective effect of grape seed oil against carbon tetrachloride induced oxidative stress in liver of γ-irradiated rat.

    PubMed

    Ismail, Amel F M; Salem, Asmaa A M; Eassawy, Mamdouh M T

    2016-07-01

    Carbon tetrachloride (CCl4) and ionizing radiation are well known environmental pollutants that generate free radicals and induce oxidative stress. The liver is the primary and major target organ responsible for the metabolism of drugs, toxic chemicals and affected by irradiation. This study investigated the effect of grape seed oil (GSO) on acute liver injury induced by carbon tetrachloride (CCl4) in γ-irradiated rats (7Gy). CCl4-intoxicated rats exhibited an elevation of ALT, AST activities, IL-6 and TNF-α level in the serum. Further, the levels of MDA, NO, NF-κB and the gene expression of CYP2E1, iNOS and Caspase-3 were increased, and SOD, CAT, GSH-Px, GST activities and GSH content were decreased. Furthermore, silent information regulator protein 1 (SIRT1) gene expression was markedly down-regulated. Additionally, alterations of the trace elements; copper, manganese, zinc and DNA fragmentation was observed in the hepatic tissues of the intoxicated group. These effects were augmented in CCl4-intoxicated-γ-irradiated rats. However, the administration of GSO ameliorated these parameters. GSO exhibit protective effects on CCl4 induced acute liver injury in γ-irradiated rats that could be attributed to its potent antioxidant, anti-inflammatory and anti-apoptotic activities. The induction of the antioxidant enzymes activities, down-regulation of the CYP2E1, iNOS, Caspase-3 and NF-κB expression, up-regulation of the trace elements concentration levels and activation of SIRT1 gene expression are responsible for the improvement of the antioxidant and anti-inflammatory status in the hepatic tissues and could be claimed to be the hepatoprotective mechanism of GSO. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Detection of irradiation induced reactive oxygen species production in live cells

    NASA Astrophysics Data System (ADS)

    Gao, Bo; Zhu, Debin

    2006-09-01

    Reactive oxygen species (ROS) is thought to play an important role in cell signaling of apoptosis, necrosis, and proliferation. Light irradiation increases mitochondrial reactive oxygen species (ROS) production and mediates its intracellular signaling by adjusting the redox potential in tumor cells. Mitochondria are the main source of ROS in the living cell. Superoxide anions (0 II - are likely the first ROS generated in the mitochondria following radiation damage, and then convert to hydrogen peroxide (H II0 II), hydroxyl radical (•OH), and singlet oxygen (10 II), etc. Conventional methods for research ROS production in mitochondria mostly use isolated mitochondria rather than mitochondria in living cells. In this study, a highly selective probe to detect mitochondrial 0 II - in live cells, MitoSOX TM Red, was applied to quantify the mitochondrial ROS production in human lung adenocarcinoma cells (ASTC-a-1) with laser scanning microscope (LSM) after ultraviolet C (UVC) and He-Ne laser irradiation. Dichiorodihydrofluoresein diacetate (DCFHDA), a common used fluorescent probe for ROS detection without specificity, were used as a comparison to image the ROS production. The fluorescent image of MItoSOX TM Red counterstained with MitoTracker Deep Red 633, a mitochondria selective probe, shows that the mitochondrial ROS production increases distinctly after UVC and He-Ne laser irradiation. DCFH-DA diffuses labeling throughout the cell though its fluorescence increases markedly too. In conclusion, the fluorescent method with MitoSOX TM Red reagent is proved to be a promising technique to research the role of ROS in radiation induced apoptosis.

  2. Thread Embedding Acupuncture Inhibits Ultraviolet B Irradiation-Induced Skin Photoaging in Hairless Mice.

    PubMed

    Kim, Yoon-Jung; Kim, Ha-Neui; Shin, Mi-Sook; Choi, Byung-Tae

    2015-01-01

    Thread embedding acupuncture (TEA) is an acupuncture treatment applied to many diseases in Korean medical clinics because of its therapeutic effects by continuous stimulation to tissues. It has recently been used to enhance facial skin appearance and antiaging, but data from evidence-based medicine are limited. To investigate whether TEA therapy can inhibit skin photoaging by ultraviolet B (UVB) irradiation, we performed analyses for histology, histopathology, in situ zymography and western blot analysis in HR-1 hairless mice. TEA treatment resulted in decreased wrinkle formation and skin thickness (Epidermis; P = 0.001 versus UV) in UVB irradiated mice and also inhibited degradation of collagen fibers (P = 0.010 versus normal) by inhibiting proteolytic activity of gelatinase matrix-metalloproteinase-9 (MMP-9). Western blot data showed that activation of c-Jun N-terminal kinase (JNK) induced by UVB (P = 0.002 versus normal group) was significantly inhibited by TEA treatment (P = 0.005 versus UV) with subsequent alleviation of MMP-9 activation (P = 0.048 versus UV). These results suggest that TEA treatment can have anti-photoaging effects on UVB-induced skin damage by maintenance of collagen density through regulation of expression of MMP-9 and related JNK signaling. Therefore, TEA therapy may have potential roles as an alternative treatment for protection against skin damage from aging.

  3. Thread Embedding Acupuncture Inhibits Ultraviolet B Irradiation-Induced Skin Photoaging in Hairless Mice

    PubMed Central

    Kim, Yoon-Jung; Kim, Ha-Neui; Shin, Mi-Sook; Choi, Byung-Tae

    2015-01-01

    Thread embedding acupuncture (TEA) is an acupuncture treatment applied to many diseases in Korean medical clinics because of its therapeutic effects by continuous stimulation to tissues. It has recently been used to enhance facial skin appearance and antiaging, but data from evidence-based medicine are limited. To investigate whether TEA therapy can inhibit skin photoaging by ultraviolet B (UVB) irradiation, we performed analyses for histology, histopathology, in situ zymography and western blot analysis in HR-1 hairless mice. TEA treatment resulted in decreased wrinkle formation and skin thickness (Epidermis; P = 0.001 versus UV) in UVB irradiated mice and also inhibited degradation of collagen fibers (P = 0.010 versus normal) by inhibiting proteolytic activity of gelatinase matrix-metalloproteinase-9 (MMP-9). Western blot data showed that activation of c-Jun N-terminal kinase (JNK) induced by UVB (P = 0.002 versus normal group) was significantly inhibited by TEA treatment (P = 0.005 versus UV) with subsequent alleviation of MMP-9 activation (P = 0.048 versus UV). These results suggest that TEA treatment can have anti-photoaging effects on UVB-induced skin damage by maintenance of collagen density through regulation of expression of MMP-9 and related JNK signaling. Therefore, TEA therapy may have potential roles as an alternative treatment for protection against skin damage from aging. PMID:26185518

  4. Non-accidental salt poisoning.

    PubMed Central

    Meadow, R

    1993-01-01

    The clinical features of 12 children who incurred non-accidental salt poisoning are reported. The children usually presented to hospital in the first six months of life with unexplained hypernatraemia and associated illness. Most of the children suffered repetitive poisoning before detection. The perpetrator was believed to the mother for 10 children, the father for one, and either parent for one. Four children had serum sodium concentrations above 200 mmol/l. Seven children had incurred other fabricated illness, drug ingestion, physical abuse, or failure to thrive/neglect. Two children died; the other 10 remained healthy in alternative care. Features are described that should lead to earlier detection of salt poisoning; the importance of checking urine sodium excretion, whenever hypernatraemia occurs, is stressed. PMID:8503665

  5. Delayed persistence of giant-nucleated cells induced by X-ray and proton irradiation in the progeny of replicating normal human f ibroblast cells

    NASA Astrophysics Data System (ADS)

    Almahwasi, A. A.; Jeynes, J. C.; Merchant, M. J.; Bradley, D. A.; Regan, P. H.

    2017-08-01

    Ionising radiation can induce giant-nucleated cells (GCs) in the progeny of irradiated populations, as demonstrated in various cellular systems. Most in vitro studies have utilised quiescent cancerous or normal cell lines but it is not clear whether radiation-induced GCs persist in the progeny of normal replicated cells. In the current work we show persistent induction of GCs in the progeny of normal human-diploid skin fibroblasts (AG1522). These cells were originally irradiated with a single equivalent clinical dose of 0.2, 1 or 2 Gy of either X-ray or proton irradiation and maintained in an active state for various post-irradiation incubation interval times before they were replated for GC analysis. The results demonstrate that the formation of GCs in the progeny of X-ray or proton irradiated cells was increased in a dose-dependent manner when measured 7 days after irradiation and this finding is in agreement with that reported for the AG1522 cells using other radiation qualities. For the 1 Gy X-ray doses it was found that the GC yield increased continually with time up to 21 days post-irradiation. These results can act as benchmark data for such work and may have important implications for studies aimed at evaluating the efficacy of radiation therapy and in determining the risk of delayed effects particularly when applying protons.

  6. Self-reported Hearing Difficulty and Risk of Accidental Injury in US Adults, 2007 to 2015.

    PubMed

    Lin, Harrison W; Mahboubi, Hossein; Bhattacharyya, Neil

    2018-03-22

    Accidental injuries are a leading cause of morbidity and mortality in the United States. Hearing problems may be associated with an increased risk for such injuries. To investigate associations between hearing difficulty and risk of accidental injuries among US adults. Cross-sectional analysis of responses of a nationally representative sample of 232.2 million individuals 18 years or older who participated in the National Health Interview Survey from 2007 to 2015 and responded to the questions related to the hearing and injury modules. The main outcome variable was accidental injury in the preceding 3 months. Hearing status was self-reported as "excellent," "good," "a little trouble," "moderate trouble," "a lot of trouble," and "deaf." Prevalence of accidental injuries was analyzed based on demographic characteristics and hearing status. Odds ratios (ORs) and 95% CIs for injuries adjusted for demographics were calculated for degrees of hearing difficulty. A secondary outcome was association of hearing status with type of injury and was classified as driving related, work related, or leisure/sport related. Of 232.2 million US adults, 120.2 million (51.7%) were female, and 116.3 million (50.1%) considered their hearing to be less than excellent. Accidental injuries occurred in 2.8% of survey respondents. In comparison with normal-hearing adults (those with self-rated excellent or good hearing), the odds of accidental injury were higher in those with a little trouble hearing (4.1%; OR, 1.6; 95% CI, 1.5-1.8), moderate trouble hearing (4.2%; OR, 1.7; 95% CI, 1.4-1.9), and a lot of trouble hearing (4.8%; OR, 1.9; 95% CI, 1.6-2.3). Work- and leisure-related injuries were more prevalent among those with self-perceived hearing difficulty. Multivariate analysis, adjusted for age and sex, revealed leisure-related injuries was most consistently associated with various degrees of hearing difficulty. Odds ratios were 1.2 (95% CI, 1.0-1.4) in those with a little trouble hearing

  7. Recruitment of Gr1(+)CD11b (+)F4/80 (+) population in the bone marrow and spleen by irradiation-induced pulmonary damage.

    PubMed

    Thanasegaran, Suganya; Ito, Sachiko; Nishio, Naomi; Uddin, Mohammad Nizam; Sun, Yang; Isobe, Ken-ichi

    2015-04-01

    Radiation-induced lung injury is a kind of sterile inflammation, which may lead to morbidity and mortality. The mechanism by which ionizing radiation activate the immune system is not well understood. In the present study, we have investigated the immunological responses induced by local irradiation-induced damage in mouse lung. The left lungs of C57BL/6 mice were irradiated at a high dose of 100 Gy. The histology of the lungs and spleen showed evidences of alveolar inflammation and congestion at 2 weeks after X-ray treatment. Also, prominent increase in cells expressing the cell surface markers, Gr(+)CD11b(+)F4/80(+) and Ly6C(+) Ly6G(+) were observed 2 weeks after X-ray treatment (100 Gy). Gr1(+)CD11b(+)F4/80(+) cell depletion by clodronate treatment reversed the histological effects and also failed to recruit Gr(+)CD11b(+) cells or F4/80(+) cells caused by irradiation. The origin of recruited Gr1(+)CD11b(+) cells was found to be a mixed resident and recruited phenotype.

  8. Insomnia medication use and the probability of an accidental event in an older adult population

    PubMed Central

    Avidan, Alon Y; Palmer, Liisa A; Doan, Justin F; Baran, Robert W

    2010-01-01

    Objective: This study examined the risk of accidental events in older adults prescribed a sedating antidepressant, long-acting benzodiazepine, short-acting benzodiazepine, and nonbenzodiazepine, relative to a reference group (selective melatonin receptor agonist). Methods: This was a retrospective cohort analysis of older adults (≥65 years) with newly initiated pharmacological treatment of insomnia. Data were collected from the Thomson MarketScan® Medicare Supplemental and Coordination of Benefits databases (January 1, 2000, through June 30, 2006). Probit models were used to evaluate the probability of an accidental event. Results: Data were analyzed for 445,329 patients. Patients taking a long-acting benzodiazepine (1.21 odds ratio [OR]), short-acting benzodiazepine (1.16 OR), or nonbenzodiazepine (1.12 OR) had a significantly higher probability of experiencing an accidental event during the first month following treatment initiation compared with patients taking the reference medication (P < 0.05 for all). A significantly higher probability of experiencing an accidental event was also observed during the 3-month period following the initiation of treatment (1.62 long-acting benzodiazepine, 1.60 short-acting benzodiazepine, 1.48 nonbenzodiazepine, and 1.56 sedating antidepressant; P < 0.05). Conclusions: Older adults taking an SAD or any of the benzodiazepine receptor agonists appear to have a greater risk of an accidental event compared with a reference group taking an MR. PMID:21701634

  9. Status of Post Irradiation Examination of FCAB and FCAT Irradiation Capsules

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Field, Kevin G.; Yamamoto, Yukinori; Howard, Richard H.

    A series of irradiation programs are ongoing to address the need for determining the radiation tolerance of FeCrAl alloys. These irradiation programs, deemed the FCAT and FCAB irradiation programs, use the High Flux Isotope Reactor (HFIR) to irradiate second generation wrought FeCrAl alloys and early-generation powder-metallurgy (PM) oxide dispersion-strengthened (ODS) FeCrAl alloys. Irradiations have been or are being performed at temperatures of 200°C, 330°C, and 550°C from doses of 1.8 dpa up to 16 dpa. Preliminary post-irradiation examination (PIE) on low dose (<2 dpa) irradiation capsules of tensile specimens has been performed. Analysis of co-irradiated SiC thermometry have shown reasonablemore » matching between the nominal irradiation temperatures and the target irradiation temperatures. Room temperature tensile tests have shown typical radiation-induced hardening and embrittlement at irradiations of 200°C and 330°C, but a propensity for softening when irradiated to 550°C for the wrought alloys. The PM-ODS FeCrAl specimens showed less hardening compared to the wrought alloys. Future PIE includes high temperature tensile tests on the low dose irradiation capsules as well as the determination of reference fracture toughness transition temperature, T o, in alloys irradiated to 7 dpa and higher.« less

  10. The Protective Effect of Baicalin against UVB Irradiation Induced Photoaging: An In Vitro and In Vivo Study

    PubMed Central

    Yin, Zhi-qiang; Hu, Yan-yan; Xu, Yang; Wu, Di; Permatasari, Felicia; Luo, Dan; Zhou, Bing-rong

    2014-01-01

    Objective This study was aimed to evaluate the anti-photoaging effects of baicalin on Ultraviolet B (UVB)-induced photoaging in the dorsal skin of hairless mice and premature senescence in human dermal fibroblasts. Methods We established in vivo and in vitro photoaging models by repeated exposures to UVB irradiation. By HE staining, masson staining, immunohistostaing and real-time RT-PCR, we analyzed epidermal thickness, collagen expression and the mRNA and protein levels of type I collagen, type III collagen, interstitial collagenase (MMP-1 and MMP-3) in UVB exposed dorsal mice skin. The aging condition in human dermal fibroblasts was determined by senescence-associated β-galactosidase (SA-β-gal) staining. Cell viability was determined using the Cell Counting Kit-8 (CCK-8). The G1 phase cell growth arrest was analyzed by flow cytometry. The senescence-related protein levels of p16INK-4a, p21WAF-1, and p53 and protein levels of phosphorylated histone H2AX were estimated by Western blotting. Results Topically application of baicalin treatment reduced UVB-induced epidermal thickening of mouse skin and also result in an increase in the production of collagen I and III, and a decrease in the expression of MMP-1 and MMP-3. Compared with the UVB-irradiated group, we found that the irradiated fibroblasts additionally treated with baicalin demonstrated a decrease in the expression of SA-β-gal, a increase in the cell viability, a decrease in the G1 phase cell proportion, a downregulation in the level of senescence-associated and γ-H2AX proteins. However, Baicalin had no difference in the normal fibroblasts without UVB irradiation and long-term Baicalin incubation of UVB-SIPS fibroblasts gave no effects on the cell proliferation. Conclusions Taken together, these results suggest that baicalin significantly antagonizes photoaging induced by UVB in vivo and in vitro, indicating the potential of baicalin application for anti-photoaging treatment. PMID:24949843

  11. The protective effect of baicalin against UVB irradiation induced photoaging: an in vitro and in vivo study.

    PubMed

    Zhang, Jia-an; Yin, Zhi; Ma, Li-wen; Yin, Zhi-qiang; Hu, Yan-yan; Xu, Yang; Wu, Di; Permatasari, Felicia; Luo, Dan; Zhou, Bing-rong

    2014-01-01

    This study was aimed to evaluate the anti-photoaging effects of baicalin on Ultraviolet B (UVB)-induced photoaging in the dorsal skin of hairless mice and premature senescence in human dermal fibroblasts. We established in vivo and in vitro photoaging models by repeated exposures to UVB irradiation. By HE staining, masson staining, immunohistostaing and real-time RT-PCR, we analyzed epidermal thickness, collagen expression and the mRNA and protein levels of type I collagen, type III collagen, interstitial collagenase (MMP-1 and MMP-3) in UVB exposed dorsal mice skin. The aging condition in human dermal fibroblasts was determined by senescence-associated β-galactosidase (SA-β-gal) staining. Cell viability was determined using the Cell Counting Kit-8 (CCK-8). The G1 phase cell growth arrest was analyzed by flow cytometry. The senescence-related protein levels of p16INK-4a, p21WAF-1, and p53 and protein levels of phosphorylated histone H2AX were estimated by Western blotting. Topically application of baicalin treatment reduced UVB-induced epidermal thickening of mouse skin and also result in an increase in the production of collagen I and III, and a decrease in the expression of MMP-1 and MMP-3. Compared with the UVB-irradiated group, we found that the irradiated fibroblasts additionally treated with baicalin demonstrated a decrease in the expression of SA-β-gal, a increase in the cell viability, a decrease in the G1 phase cell proportion, a downregulation in the level of senescence-associated and γ-H2AX proteins. However, Baicalin had no difference in the normal fibroblasts without UVB irradiation and long-term Baicalin incubation of UVB-SIPS fibroblasts gave no effects on the cell proliferation. Taken together, these results suggest that baicalin significantly antagonizes photoaging induced by UVB in vivo and in vitro, indicating the potential of baicalin application for anti-photoaging treatment.

  12. Effects of cadmium and zinc on solar-simulated light-irradiated cells: potential role of zinc-metallothionein in zinc-induced genoprotection.

    PubMed

    Jourdan, Eric; Emonet-Piccardi, Nathalie; Didier, Christine; Beani, Jean-Claude; Favier, Alain; Richard, Marie-Jeanne

    2002-09-15

    Zinc is an essential oligoelement for cell growth and cell survival and has been demonstrated to protect cells from oxidative stress induced by UVA or from genotoxic stress due to UVB. In a recent work we demonstrated that the antioxidant role of zinc could be related to its ability to induce metallothioneins (MTs). In this study we identified the mechanism of zinc protection against solar-simulated light (SSL) injury. Cultured human keratinocytes (HaCaT) were used to examine MTs expression and localization in response to solar-simulated radiation. We found translocation to the nucleus, with overexpression of MTs in irradiated cells, a novel observation. The genoprotective effect of zinc was dependent on time and protein synthesis. DNA damage was significantly decreased after 48 h of ZnCl(2) (100 microM) treatment and is inhibited by actinomycin D. ZnCl(2) treatment (100 microM) led to an intense induction, redistribution, and accumulation of MT in the nucleus of irradiated cells. MT expression correlated with the time period of ZnCl(2) treatment. CdCl(2), a potent MT inducer, did not show any genoprotection, although the MTs were expressed in the nucleus. Overall our findings demonstrate that MTs could be a good candidate for explaining the genoprotection mediated by zinc on irradiated cells.

  13. The Association between Dust Storms and Daily Non-Accidental Mortality in the United States, 1993-2005.

    PubMed

    Crooks, James Lewis; Cascio, Wayne E; Percy, Madelyn S; Reyes, Jeanette; Neas, Lucas M; Hilborn, Elizabeth D

    2016-11-01

    The impact of dust storms on human health has been studied in the context of Asian, Saharan, Arabian, and Australian storms, but there has been no recent population-level epidemiological research on the dust storms in North America. The relevance of dust storms to public health is likely to increase as extreme weather events are predicted to become more frequent with anticipated changes in climate through the 21st century. We examined the association between dust storms and county-level non-accidental mortality in the United States from 1993 through 2005. Dust storm incidence data, including date and approximate location, are taken from the U.S. National Weather Service storm database. County-level mortality data for the years 1993-2005 were acquired from the National Center for Health Statistics. Distributed lag conditional logistic regression models under a time-stratified case-crossover design were used to study the relationship between dust storms and daily mortality counts over the whole United States and in Arizona and California specifically. End points included total non-accidental mortality and three mortality subgroups (cardiovascular, respiratory, and other non-accidental). We estimated that for the United States as a whole, total non-accidental mortality increased by 7.4% (95% CI: 1.6, 13.5; p = 0.011) and 6.7% (95% CI: 1.1, 12.6; p = 0.018) at 2- and 3-day lags, respectively, and by an average of 2.7% (95% CI: 0.4, 5.1; p = 0.023) over lags 0-5 compared with referent days. Significant associations with non-accidental mortality were estimated for California (lag 2 and 0-5 day) and Arizona (lag 3), for cardiovascular mortality in the United States (lag 2) and Arizona (lag 3), and for other non-accidental mortality in California (lags 1-3 and 0-5). Dust storms are associated with increases in lagged non-accidental and cardiovascular mortality. Citation: Crooks JL, Cascio WE, Percy MS, Reyes J, Neas LM, Hilborn ED. 2016. The association between dust storms

  14. Dirac cones induced by accidental degeneracy in photonic crystals and zero-refractive-index materials.

    PubMed

    Huang, Xueqin; Lai, Yun; Hang, Zhi Hong; Zheng, Huihuo; Chan, C T

    2011-05-29

    A zero-refractive-index metamaterial is one in which waves do not experience any spatial phase change, and such a peculiar material has many interesting wave-manipulating properties. These materials can in principle be realized using man-made composites comprising metallic resonators or chiral inclusions, but metallic components have losses that compromise functionality at high frequencies. It would be highly desirable if we could achieve a zero refractive index using dielectrics alone. Here, we show that by employing accidental degeneracy, dielectric photonic crystals can be designed and fabricated that exhibit Dirac cone dispersion at the centre of the Brillouin zone at a finite frequency. In addition to many interesting properties intrinsic to a Dirac cone dispersion, we can use effective medium theory to relate the photonic crystal to a material with effectively zero permittivity and permeability. We then numerically and experimentally demonstrate in the microwave regime that such dielectric photonic crystals with reasonable dielectric constants manipulate waves as if they had near-zero refractive indices at and near the Dirac point frequency.

  15. Microarray analysis of miRNA expression profiles following whole body irradiation in a mouse model.

    PubMed

    Aryankalayil, Molykutty J; Chopra, Sunita; Makinde, Adeola; Eke, Iris; Levin, Joel; Shankavaram, Uma; MacMillan, Laurel; Vanpouille-Box, Claire; Demaria, Sandra; Coleman, C Norman

    2018-06-19

    Accidental exposure to life-threatening radiation in a nuclear event is a major concern; there is an enormous need for identifying biomarkers for radiation biodosimetry to triage populations and treat critically exposed individuals. To identify dose-differentiating miRNA signatures from whole blood samples of whole body irradiated mice. Mice were whole body irradiated with X-rays (2 Gy-15 Gy); blood was collected at various time-points post-exposure; total RNA was isolated; miRNA microarrays were performed; miRNAs differentially expressed in irradiated vs. unirradiated controls were identified; feature extraction and classification models were applied to predict dose-differentiating miRNA signature. We observed a time and dose responsive alteration in the expression levels of miRNAs. Maximum number of miRNAs were altered at 24-h and 48-h time-points post-irradiation. A 23-miRNA signature was identified using feature selection algorithms and classifier models. An inverse correlation in the expression level changes of miR-17 members, and their targets were observed in whole body irradiated mice and non-human primates. Whole blood-based miRNA expression signatures might be used for predicting radiation exposures in a mass casualty nuclear incident.

  16. Study on accumulated crystallization characteristics of amorphous Ge2Sb2Te5 induced by multi-pulsed laser irradiations with different fluences

    NASA Astrophysics Data System (ADS)

    Fan, T.; Liu, F. R.; Li, W. Q.; Guo, J. C.; Wang, Y. H.; Sun, N. X.; Liu, F.

    2018-07-01

    Accumulated crystallization characteristics of amorphous Ge2Sb2Te5 (a-GST) films induced by multi-pulsed laser irradiations with different fluences were investigated by x-ray diffraction (XRD), Raman spectroscopy and spectrophotometer. Solid-state transformation was performed at low fluence (LF, 30.5 mJ cm‑2), whereas melting-cooling transformation dominated at medium and high fluence (MF, 45.7 and HF, 61 mJ cm‑2). Solid-state transformation induced by subsequent LF pulses promoted the growth and coalescence of grains, linearly increasing the average grain size, accordingly causing blue-shifts of the Raman spectral peaks. For MF/HF pulse irradiated films, the relatively high laser fluence increased the melting depth and reduced the volume fraction of the crystalline state induced by individual pulses, thereby increasing the threshold of laser pulse numbers for XRD detectable crystallization. However, the remelting depth induced by subsequent MF/HF laser pulse progressively decreased. The remelting-recrystallization process refined grain sizes, which improved the red-shifts of Raman spectral peaks. Moreover, optical contrast increased dramatically compared to single laser irradiation and five-level storage could be realized for a linear increase of optical contrast. The present study is fundamental for realizing the potential of multi-level devices.

  17. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the Director, Center for Devices and Radiological Health, all accidental radiation occurrences... grounds include, but are not necessarily limited to, professional, scientific, or medical facts or... occurred. (b) Such reports shall be addressed to the Center for Devices and Radiological Health, ATTN...

  18. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the Director, Center for Devices and Radiological Health, all accidental radiation occurrences... grounds include, but are not necessarily limited to, professional, scientific, or medical facts or... occurred. (b) Such reports shall be addressed to Food and Drug Administration, Center for Devices and...

  19. GaAlAs laser irradiation induces active tertiary dentin formation after pulpal apoptosis and cell proliferation in rat molars.

    PubMed

    Shigetani, Yoshimi; Sasa, Natsuki; Suzuki, Hironobu; Okiji, Takashi; Ohshima, Hayato

    2011-08-01

    This study aimed to clarify pulpal responses to gallium-aluminum-arsenide (GaAlAs) laser irradiation. Maxillary first molars of 8-week-old rats were irradiated at an output power of 0.5 or 1.5 W for 180 seconds, and the samples were collected at intervals of 0 to 14 days. The demineralized paraffin sections were processed for immunohistochemistry for heat-shock protein (HSP)-25 and nestin in addition to cell proliferation assay using bromodeoxyuridine (BrdU) labeling and apoptosis assay using deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL). Intense HSP-25 and nestin immunoreactivities in the odontoblast layer were weakened immediately after 0.5-W irradiation and recovered on day 1, resulting in slight tertiary dentin formation by day 14. On the contrary, 1.5-W irradiation immediately induced the loss of HSP-25 and nestin-immunoreactivities in the odontoblast layer. On day 1, numerous TUNEL-positive cells appeared in a degenerative zone that was surrounded by intense HSP-25 immunoreactivity. BrdU-positive cells occurred within the intensely HSP-25-immunopositive areas during days 2 through 5, whereas TUNEL-positive cells gradually decreased in number by day 5. HSP-25- and nestin-positive odontoblast-like cells were arranged along the pulp-dentin border by day 7, resulting in remarkable tertiary dentin formation on day 14. The output energy determined pulpal healing patterns after GaAlAs laser irradiation; the higher energy induced the apoptosis in the affected dental pulp including odontoblasts followed by active cell proliferation in the intense HSP-25-immunoreactive areas surrounding the degenerative tissue, resulting in abundant tertiary dentin formation. Thus, the optimal GaAlAs laser irradiation elicited intentional tertiary dentin formation in the dental pulp. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  20. Determinants of suicide and accidental or violent death in the Australian HIV Observational Database.

    PubMed

    McManus, Hamish; Petoumenos, Kathy; Franic, Teo; Kelly, Mark D; Watson, Jo; O'Connor, Catherine C; Jeanes, Mark; Hoy, Jennifer; Cooper, David A; Law, Matthew G

    2014-01-01

    Rates of suicide and accidental or violent death remain high in HIV-positive populations despite significantly improved prognosis since the introduction of cART. We conducted a nested case-control study of suicide and accidental or violent death in the Australian HIV Observational Database (AHOD) between January 1999 and March 2012. For each case, 2 controls were matched by clinic, age, sex, mode of exposure and HIV-positive date to adjust for potential confounding by these covariates. Risk of suicide and accidental or violent death was estimated using conditional logistic regression. We included 27 cases (17 suicide and 10 violent/accidental death) and 54 controls. All cases were men who have sex with men (MSM) or MSM/ injecting drug use (IDU) mode of exposure. Increased risk was associated with unemployment (Odds Ratio (OR) 5.86, 95% CI: 1.69-20.37), living alone (OR 3.26, 95% CI: 1.06-10.07), suicidal ideation (OR 6.55, 95% CI: 1.70-25.21), and >2 psychiatric/cognitive risk factors (OR 4.99, 95% CI: 1.17-30.65). CD4 cell count of >500 cells/µL (OR 0.25, 95% CI: 0.07-0.87) and HIV-positive date ≥1990 (1990-1999 (OR 0.31, 95% CI: 0.11-0.89), post-2000 (OR 0.08, 95% CI: 0.01-0.84)) were associated with decreased risk. CD4 cell count ≥500 cells/µL remained a significant predictor of reduced risk (OR 0.15, 95% CI: 0.03-0.70) in a multivariate model adjusted for employment status, accommodation status and HIV-positive date. After adjustment for psychosocial factors, the immunological status of HIV-positive patients contributed to the risk of suicide and accidental or violent death. The number of psychiatric/cognitive diagnoses contributed to the level of risk but many psychosocial factors were not individually significant. These findings indicate a complex interplay of factors associated with risk of suicide and accidental or violent death.

  1. Cervical spine injuries in young children: pattern and outcomes in accidental versus inflicted trauma.

    PubMed

    Baerg, Joanne; Thirumoorthi, Arul; Hazboun, Rajaie; Vannix, Rosemary; Krafft, Paul; Zouros, Alexander

    2017-11-01

    The aim of the study was to compare the cervical spine (c-spine) pattern of injury and outcomes in children below 3 y with a head injury from confirmed inflicted versus accidental trauma. After Institutional Review Board approval, data were prospectively collected between July 2011 and January 2016. Inclusion criteria were age below 3 y, a loss of consciousness, and any one of the following initial head computed tomography (CT) findings (subdural hematoma, intraventricular, intraparenchymal, subarachnoid hemorrhage, or cerebral edema). A protocol of brain and neck magnetic resonance imaging and magnetic resonance angiography was instituted. Brain and neck imaging results, clinical variables, and outcomes were recorded. Data were compared by t-test for continuous and Fisher exact test for categorical variables. 73 children were identified, 52 (71%) with inflicted and 21 (29%) with accidental trauma. The median age was 11 mo; (range: 1-35 mo). Ten (14%) had c-spine injuries, 7/52 (13%) inflicted, and 3/21 (14%) accidental. The mechanism was shaking for all inflicted and motor vehicle accident or pedestrian struck for accidental c-spine injuries. The inflicted group were significantly younger (P = 0.03), had higher Injury Severity Scores (P = 0.02), subdural hematomas (P = 0.03), fractures (P = 0.03), retinal hemorrhages (P = 0.02), brain infarcts (P = 0.01), and required cardiopulmonary resuscitation (P = 0.01). Seven with inflicted trauma died from brain injury (9.5%), one had atlanto-occipital dissociation. Six mortalities (86%) had no c-spine injury. Six with inflicted c-spine injuries survived with neurologic impairment, whereas three with accidental survived without disability, including one atlanto-occipital dissociation. Compared to accidental trauma, young children with inflicted c-spine injuries have more multisystem trauma, long-term disability from brain injury, and an injury pattern consistent with shaking. Copyright © 2017 Elsevier Inc

  2. Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset.

    PubMed

    Gualde, N; Goodwin, J S

    1984-04-01

    Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less [3H]thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced [3H]thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), and OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset.

  3. Topical Formulation Containing Naringenin: Efficacy against Ultraviolet B Irradiation-Induced Skin Inflammation and Oxidative Stress in Mice

    PubMed Central

    Martinez, Renata M.; Pinho-Ribeiro, Felipe A.; Steffen, Vinicius S.; Silva, Thais C. C.; Caviglione, Carla V.; Bottura, Carolina; Fonseca, Maria J. V.; Vicentini, Fabiana T. M. C.; Vignoli, Josiane A.; Baracat, Marcela M.; Georgetti, Sandra R.; Verri, Waldiceu A.; Casagrande, Rubia

    2016-01-01

    Naringenin (NGN) exhibits anti-inflammatory and antioxidant activities, but it remains undetermined its topical actions against ultraviolet B (UVB)-induced inflammation and oxidative stress in vivo. The purpose of this study was to evaluate the physicochemical and functional antioxidant stability of NGN containing formulations, and the effects of selected NGN containing formulation on UVB irradiation-induced skin inflammation and oxidative damage in hairless mice. NGN presented ferric reducing power, ability to scavenge 2,2′-azinobis (3-ethylbenzothiazoline- 6-sulfonic acid) (ABTS) and hydroxyl radical, and inhibited iron-independent and dependent lipid peroxidation. Among the three formulations containing NGN, only the F3 kept its physicochemical and functional stability over 180 days. Topical application of F3 in mice protected from UVB-induced skin damage by inhibiting edema and cytokine production (TNF-α, IL-1β, IL-6, and IL-10). Furthermore, F3 inhibited superoxide anion and lipid hydroperoxides production and maintained ferric reducing and ABTS scavenging abilities, catalase activity, and reduced glutathione levels. In addition, F3 maintained mRNA expression of cellular antioxidants glutathione peroxidase 1, glutathione reductase and transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2), and induced mRNA expression of heme oxygenase-1. In conclusion, a formulation containing NGN may be a promising approach to protecting the skin from the deleterious effects of UVB irradiation. PMID:26741806

  4. Ion irradiation induced nucleation and growth of nanoparticles in amorphous silicon carbide at elevated temperatures

    DOE PAGES

    Zhang, Limin; Jiang, Weilin; Ai, Wensi; ...

    2018-04-04

    Ion irradiation induced crystallization in as-deposited amorphous SiC films is investigated using grazing-angle incidence x-ray diffraction (GIXRD), transmission electron microscopy (TEM) and Raman spectroscopy. Irradiation with 5 MeV Xe to fluence of 1.15 ×10 16 Xe/cm 2 at 700 K results in a homogenous distribution of 3C-SiC grains with an average crystallite size of ~5.7 nm over the entire film thickness (~1 μm). The nucleation and growth processes exhibit a weak dependence on dose in displacements per atom (dpa) in the range from ~6 dpa at the film surface to ~20 dpa at the SiC/Si interface. A transformation of homonuclearmore » C-C bonds from sp 3 to sp 2 hybridization is observed in the irradiated films, which may be partly responsible for the observed grain size saturation. Lastly, the results from this study may have a significant impact on applications of SiC as structural components of advanced nuclear energy systems.« less

  5. Ion irradiation induced nucleation and growth of nanoparticles in amorphous silicon carbide at elevated temperatures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Limin; Jiang, Weilin; Ai, Wensi

    Ion irradiation induced crystallization in as-deposited amorphous SiC films is investigated using grazing-angle incidence x-ray diffraction (GIXRD), transmission electron microscopy (TEM) and Raman spectroscopy. Irradiation with 5 MeV Xe to fluence of 1.15 ×10 16 Xe/cm 2 at 700 K results in a homogenous distribution of 3C-SiC grains with an average crystallite size of ~5.7 nm over the entire film thickness (~1 μm). The nucleation and growth processes exhibit a weak dependence on dose in displacements per atom (dpa) in the range from ~6 dpa at the film surface to ~20 dpa at the SiC/Si interface. A transformation of homonuclearmore » C-C bonds from sp 3 to sp 2 hybridization is observed in the irradiated films, which may be partly responsible for the observed grain size saturation. Lastly, the results from this study may have a significant impact on applications of SiC as structural components of advanced nuclear energy systems.« less

  6. Ion irradiation induced nucleation and growth of nanoparticles in amorphous silicon carbide at elevated temperatures

    NASA Astrophysics Data System (ADS)

    Zhang, Limin; Jiang, Weilin; Ai, Wensi; Chen, Liang; Wang, Tieshan

    2018-07-01

    Ion irradiation induced crystallization in as-deposited amorphous SiC films is investigated using grazing-angle incidence x-ray diffraction (GIXRD), transmission electron microscopy (TEM) and Raman spectroscopy. Irradiation with 5 MeV Xe to fluence of 1.15 × 1016 Xe/cm2 at 700 K results in a homogenous distribution of 3C-SiC grains with an average crystallite size of ∼5.7 nm over the entire film thickness (∼1 μm). The nucleation and growth processes exhibit a weak dependence on dose in displacements per atom (dpa) in the range from ∼6 dpa at the film surface to ∼20 dpa at the SiC/Si interface. A transformation of homonuclear C-C bonds from sp3 to sp2 hybridization is observed in the irradiated films, which may be partly responsible for the observed grain size saturation. The results from this study may have a significant impact on applications of SiC as structural components of advanced nuclear energy systems.

  7. Accidental Peccei-Quinn Symmetry Protected to Arbitrary Order

    NASA Astrophysics Data System (ADS)

    Di Luzio, Luca; Nardi, Enrico; Ubaldi, Lorenzo

    2017-07-01

    A S U (N )L×S U (N )R gauge theory for a scalar multiplet Y transforming in the bifundamental representation (N ,N ¯) preserves, for N >4 , an accidental U (1 ) symmetry first broken at operator dimension N . A vacuum expectation value for Y can break the symmetry to Hs=S U (N )L+R or to Hh=S U (N -1 )L×S U (N -1 )R×U (1 )L +R . In the first case the accidental U (1 ) gets also broken, yielding a pseudo-Nambu-Goldstone boson with mass suppression controlled by N . In the second case a global U (1 ) remains unbroken. The strong C P problem is solved by coupling Y to new fermions carrying color. The first case allows for a Peccei-Quinn solution with U (1 )PQ protected by the gauge symmetry up to order N . In the second case U (1 ) can get broken by condensates of the new strong dynamics, resulting in a composite axion. By coupling Y to fermions carrying only weak isospin, models for axionlike particles can be constructed.

  8. Accidental Beam Losses and Protection in the LHC

    NASA Astrophysics Data System (ADS)

    Schmidt, R.; Working Group On Machine Protection

    2005-06-01

    At top energy (proton momentum 7 TeV/c) with nominal beam parameters, each of the two LHC proton beams has a stored energy of 350 MJ threatening to damage accelerator equipment in case of accidental beam loss. It is essential that the beams are properly extracted onto the dump blocks in case of failure since these are the only elements that can withstand full beam impact. Although the energy stored in the beams at injection (450 GeV/c) is about 15 times smaller compared to top energy, the beams must still be properly extracted in case of large accidental beam losses. Failures must be detected at a sufficiently early stage and initiate a beam dump. Quenches and power converter failures will be detected by monitoring the correct functioning of the hardware systems. In addition, safe operation throughout the cycle requires the use of beam loss monitors, collimators and absorbers. Ideas of detection of fast beam current decay, monitoring of fast beam position changes and monitoring of fast magnet current changes are discussed, to provide the required redundancy for machine protection.

  9. Smad, but not MAPK, pathway mediates the expression of type I collagen in radiation induced fibrosis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yano, Hiroyuki; Division of Radioisotope Research, Department of Research Support, Research Promotion Project, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593; Hamanaka, Ryoji

    Highlights: Black-Right-Pointing-Pointer We examine how radiation affects the expression level and signal pathway of collagen. Black-Right-Pointing-Pointer TGF-{beta}1 mRNA is elevated earlier than those of collagen genes after irradiation. Black-Right-Pointing-Pointer Smad pathway mediates the expression of collagen in radiation induced fibrosis. Black-Right-Pointing-Pointer MAPK pathways are not affected in the expression of collagen after irradiation. -- Abstract: Radiation induced fibrosis occurs following a therapeutic or accidental radiation exposure in normal tissues. Tissue fibrosis is the excessive accumulation of collagen and other extracellular matrix components. This study investigated how ionizing radiation affects the expression level and signal pathway of type I collagen. Realmore » time RT-RCR showed that both {alpha}1and {alpha}2 chain of type I collagen mRNA were elevated from 48 h after irradiation with 10 Gy in NIH3T3 cells. The relative luciferase activities of both genes and type I collagen marker were elevated at 72 h. TGF-{beta}1 mRNA was elevated earlier than those of type I collagen genes. A Western blot analysis showed the elevation of Smad phosphorylation at 72 h. Conversely, treatment with TGF-{beta} receptor inhibitor inhibited the mRNA and relative luciferase activity of type I collagen. The phosphorylation of Smad was repressed with the inhibitor, and the luciferase activity was cancelled using a mutant construct of Smad binding site of {alpha}2(I) collagen gene. However, the MAPK pathways, p38, ERK1/2 and JNK, were not affected with specific inhibitors or siRNA. The data showed that the Smad pathway mediated the expression of type I collagen in radiation induced fibrosis.« less

  10. Effect of He+ fluence on surface morphology and ion-irradiation induced defect evolution in 7075 aluminum alloys

    NASA Astrophysics Data System (ADS)

    Ni, Kai; Ma, Qian; Wan, Hao; Yang, Bin; Ge, Junjie; Zhang, Lingyu; Si, Naichao

    2018-02-01

    The evolution of microstructure for 7075 aluminum alloys with 50 Kev helium ions irradiation were studied by using optical microscopy (OM), scanning electron microscopy (SEM), x-ray diffraction (XRD) and transmission electron microscopy (TEM). The fluences of 1 × 1015, 1 × 1016 and 1 × 1017 ions cm-2 were selected, and irradiation experiments were conducted at room temperatures. The transmission process of He+ ions was simulated by using SRIM software, including distribution of ion ranges, energy losses and atomic displacements. Experimental results show that irradiated pits and micro-cracks were observed on irradiation sample surface, and the size of constituent particles (not including Mg2Si) decreased with the increasing dose. The x-ray diffraction results of the pair of peaks is better resolved in irradiated samples might indicate that the stressed structure consequence due to crystal defects (vacancies and interstitials) after He+ implantation. TEM observation indicated that the density of MgZn2 phase was significantly reduced after helium ion irradiation which is harmful to strength. Besides, the development of compressive stress produced a large amount of dislocation defects in the 1015 ions cm-2 sample. Moreover, higher fluence irradiation produced more dislocations in sample. At fluence of 1016 ions cm-2, dislocation wall formed by dislocation slip and aggregation in the interior of grains, leading to the refinement of these grains. As fluence increased to 1017 ions cm-2, dislocation loops were observed in pinned dislocation. Moreover, dislocation as effective defect sink, irradiation-induced vacancy defects aggregated to these sinks, and resulted in the formation of helium bubbles in dislocation.

  11. Mentha piperita as a pivotal neuro-protective agent against gamma irradiation induced DNA fragmentation and apoptosis : Mentha extract as a neuroprotective against gamma irradiation.

    PubMed

    Hassan, Hanaa A; Hafez, Hani S; Goda, Mona S

    2013-01-01

    Ionizing radiation is classified as a potent carcinogen, and its injury to living cells, in particular to DNA, is due to oxidative stress enhancing apoptotic cell death. Our present study aimed to characterize and semi-quantify the radiation-induced apoptosis in CNS and the activity of Mentha extracts as neuron-protective agent. Our results through flow cytometry exhibited the significant disturbance and arrest in cell cycle in % of M1: SubG1 phase, M2: G0/1 phase of diploid cycle, M3: S phase and M4: G2/M phase of cell cycle in brain tissue (p < 0.05). Significant increase in % of apoptosis and P53 protein expression as apoptotic biomarkers were coincided with significant decrease in Bcl(2) as an anti-apoptotic marker. The biochemical analysis recorded a significant decrease in the levels of reduced glutathione, superoxide dismutase, deoxyribonucleic acid (DNA) and ribonucleic acid contents. Moreover, numerous histopathological alterations were detected in brain tissues of gamma irradiated mice such as signs of chromatolysis in pyramidal cells of cortex, nuclear vacuolation, numerous apoptotic cell, and neural degeneration. On the other hand, gamma irradiated mice pretreated with Mentha extract showed largely an improvement in all the above tested parameters through a homeostatic state for the content of brain apoptosis and stabilization of DNA cycle with a distinct improvement in cell cycle analysis and antioxidant defense system. Furthermore, the aforementioned effects of Mentha extracts through down-regulation of P53 expression and up-regulation of Bcl(2) domain protected brain structure from extensive damage. Therefore, Mentha extract seems to have a significant role to ameliorate the neuronal injury induced by gamma irradiation.

  12. Formation of laser-induced periodic surface structures on fused silica upon two-color double-pulse irradiation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Höhm, S.; Herzlieb, M.; Rosenfeld, A.

    2013-12-16

    The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of fused silica with multiple irradiation sequences consisting of laser pulse pairs (50 fs single-pulse duration) of two different wavelengths (400 and 800 nm) is studied experimentally. Parallel polarized double-pulse sequences with a variable delay Δt between −10 and +10 ps and between the individual fs-laser pulses were used to investigate the LIPSS periods versus Δt. These two-color experiments reveal the importance of the ultrafast energy deposition to the silica surface by the first laser pulse for LIPSS formation. The second laser pulse subsequently reinforces the previously seeded spatial LIPSSmore » frequencies.« less

  13. The Accidental Transgressor: Morally-Relevant Theory of Mind

    ERIC Educational Resources Information Center

    Killen, Melanie; Mulvey, Kelly Lynn; Richardson, Cameron; Jampol, Noah; Woodward, Amanda

    2011-01-01

    To test young children's false belief theory of mind in a morally relevant context, two experiments were conducted. In Experiment 1, children (N=162) at 3.5, 5.5, and 7.5 years of age were administered three tasks: prototypic moral transgression task, false belief theory of mind task (ToM), and an "accidental transgressor" task, which measured a…

  14. Positive income shocks and accidental deaths among Cherokee Indians: a natural experiment

    PubMed Central

    Bruckner, Tim A; Brown, Ryan A; Margerison-Zilko, Claire

    2011-01-01

    Background Several studies in low-income populations report the somewhat counterintuitive finding that positive income gains adversely affect adult health. The literature posits that receipt of a large portion of annual income increases, in the short term, risk-taking behaviour and/or the consumption of health-damaging goods. This work implies the hypothesis that persons with an unexpected gain in income will exhibit an elevated risk of accidental death—the fifth leading cause of death in the USA. We test this hypothesis directly by capitalizing on a natural experiment in which Cherokee Indians in rural North Carolina received discrete lump sum payments from a new casino. Methods We applied Poisson regression to the monthly count of accidental deaths among Cherokee Indians over 204 months spanning 1990–2006. We controlled for temporal patterns in accidental deaths (e.g. seasonality and trend) as well as changes in population size. Results As hypothesized, the risk of accidental death rises above expected levels during months of the large casino payments (relative risk = 2.62; 95% confidence interval = 1.54–4.47). Exploratory analyses of ethnographic interviews and behavioural surveys support that increased vehicular travel and consumption of health-damaging goods may account for the rise in accident proneness. Conclusions Although long-term income gains may improve health in this population, our findings indicate that acute responses to large income gains, in the short term, increase risk-taking and accident proneness. We encourage further investigation of natural experiments to identify causal economic antecedents of population health. PMID:21527447

  15. The Impacts of Air Temperature on Accidental Casualties in Beijing, China.

    PubMed

    Ma, Pan; Wang, Shigong; Fan, Xingang; Li, Tanshi

    2016-11-02

    Emergency room (ER) visits for accidental casualties, according to the International Classification of Deceases 10th Revision Chapters 19 and 20, include injury, poisoning, and external causes (IPEC). Annual distribution of 187,008 ER visits that took place between 2009 and 2011 in Beijing, China displayed regularity rather than random characteristics. The annual cycle from the Fourier series fitting of the number of ER visits was found to explain 63.2% of its total variance. In this study, the possible effect and regulation of meteorological conditions on these ER visits are investigated through the use of correlation analysis, as well as statistical modeling by using the Distributed Lag Non-linear Model and Generalized Additive Model. Correlation analysis indicated that meteorological variables that positively correlated with temperature have a positive relationship with the number of ER visits, and vice versa. The temperature metrics of maximum, minimum, and mean temperatures were found to have similar overall impacts, including both the direct impact on human mental/physical conditions and indirect impact on human behavior. The lag analysis indicated that the overall impacts of temperatures higher than the 50th percentile on ER visits occur immediately, whereas low temperatures show protective effects in the first few days. Accidental casualties happen more frequently on warm days when the mean temperature is higher than 14 °C than on cold days. Mean temperatures of around 26 °C result in the greatest possibility of ER visits for accidental casualties. In addition, males were found to face a higher risk of accidental casualties than females at high temperatures. Therefore, the IPEC-classified ER visits are not pure accidents; instead, they are associated closely with meteorological conditions, especially temperature.

  16. Electron beam irradiation effects on ethylene-tetrafluoroethylene copolymer films

    NASA Astrophysics Data System (ADS)

    Nasef, Mohamed Mahmoud; Saidi, Hamdani; Dahlan, Khairul Zaman M.

    2003-12-01

    The effects of electron beam irradiation on ethylene-tetrafluoroethylene copolymer (ETFE) films were studied. Samples were irradiated in air at room temperature by a universal electron beam accelerator for doses ranging from 100 to 1200 kGy. Irradiated samples were investigated with respect to their chemical structure, thermal characteristics, crystallinity and mechanical properties using FTIR, differential scanning calorimeter (DSC) and universal mechanical tester. The interaction of electron irradiation with ETFE films was found to induce dose-dependent changes in all the investigated properties. A mechanism for electron-induced reactions is proposed to explain the structure-property behaviour of irradiated ETFE films.

  17. Calcium influx through TRP channels induced by short-lived reactive species in plasma-irradiated solution

    NASA Astrophysics Data System (ADS)

    Sasaki, Shota; Kanzaki, Makoto; Kaneko, Toshiro

    2016-05-01

    Non-equilibrium helium atmospheric-pressure plasma (He-APP), which allows for a strong non-equilibrium chemical reaction of O2 and N2 in ambient air, uniquely produces multiple extremely reactive products, such as reactive oxygen species (ROS), in plasma-irradiated solution. We herein show that relatively short-lived unclassified reactive species (i.e., deactivated within approximately 10 min) generated by the He-APP irradiation can trigger physiologically relevant Ca2+ influx through ruthenium red- and SKF 96365-sensitive Ca2+-permeable channel(s), possibly transient receptor potential channel family member(s). Our results provide novel insight into understanding of the interactions between cells and plasmas and the mechanism by which cells detect plasma-induced chemically reactive species, in addition to facilitating development of plasma applications in medicine.

  18. Accidental neutron dosimetry with human hair

    NASA Astrophysics Data System (ADS)

    Ekendahl, Daniela; Bečková, Věra; Zdychová, Vlasta; Bulánek, Boris; Prouza, Zdeněk; Štefánik, Milan

    2014-11-01

    Human hair contains sulfur, which can be activated by fast neutrons. The 32S(n,p)32P reaction with a threshold of 2.5 MeV was used for fast neutron dose estimation. It is a very important parameter for individual dose reconstruction with regards to the heterogeneity of the neutron transfer to the human body. Samples of human hair were irradiated in a radial channel of a training reactor VR-1. 32P activity in hair was measured both, directly by means of a proportional counter, and as ash dispersed in a liquid scintillator. Based on neutron spectrum estimation, a relationship between the neutron dose and induced activity was derived. The experiment verified the practical feasibility of this dosimetry method in cases of criticality accidents or malevolent acts with nuclear materials.

  19. Non-random distribution of DNA double-strand breaks induced by particle irradiation

    NASA Technical Reports Server (NTRS)

    Lobrich, M.; Cooper, P. K.; Rydberg, B.; Chatterjee, A. (Principal Investigator)

    1996-01-01

    Induction of DNA double-strand breaks (dsbs) in mammalian cells is dependent on the spatial distribution of energy deposition from the ionizing radiation. For high LET particle radiations the primary ionization sites occur in a correlated manner along the track of the particles, while for X-rays these sites are much more randomly distributed throughout the volume of the cell. It can therefore be expected that the distribution of dsbs linearly along the DNA molecule also varies with the type of radiation and the ionization density. Using pulsed-field gel and conventional gel techniques, we measured the size distribution of DNA molecules from irradiated human fibroblasts in the total range of 0.1 kbp-10 Mbp for X-rays and high LET particles (N ions, 97 keV/microns and Fe ions, 150 keV/microns). On a mega base pair scale we applied conventional pulsed-field gel electrophoresis techniques such as measurement of the fraction of DNA released from the well (FAR) and measurement of breakage within a specific NotI restriction fragment (hybridization assay). The induction rate for widely spaced breaks was found to decrease with LET. However, when the entire distribution of radiation-induced fragments was analysed, we detected an excess of fragments with sizes below about 200 kbp for the particles compared with X-irradiation. X-rays are thus more effective than high LET radiations in producing large DNA fragments but less effective in the production of smaller fragments. We determined the total induction rate of dsbs for the three radiations based on a quantitative analysis of all the measured radiation-induced fragments and found that the high LET particles were more efficient than X-rays at inducing dsbs, indicating an increasing total efficiency with LET. Conventional assays that are based only on the measurement of large fragments are therefore misleading when determining total dsb induction rates of high LET particles. The possible biological significance of this non

  20. Radiation damage induced in Al2O3 single crystal sequentially irradiated with reactor neutrons and 90 MeV Xe ions

    NASA Astrophysics Data System (ADS)

    Zirour, H.; Izerrouken, M.; Sari, A.

    2016-06-01

    The present investigation reports the effect of 90 MeV Xe ion irradiation on neutron irradiated Al2O3 single crystals. Three irradiation experiments were performed, with neutrons only, 90 MeV Xe ions only and with neutrons followed by 90 MeV Xe ions. Neutron and 90 MeV Xe ion irradiations were performed at NUR research reactor, Algiers, Algeria and at GANIL accelerator, Caen, France respectively. After irradiation, the radiation damage was investigated by Raman spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), optical absorption measurements, and X-ray diffraction (XRD) techniques. Raman technique revealed that the concentration of the defects formed in Al2O3 samples subsequently irradiated with neutrons and 90 MeV Xe ions is lower than that formed in Al2O3 samples which were irradiated only with neutrons. This reveals the occurrence of ionization-induced recovery of the neutron damage. Furthermore, as revealed by XRD analysis, a new peak is appeared at about 2θ = 38.03° after irradiation at high fluence (>3 × 1013 Xe/cm2). It can be assigned to the formation of new lattice plane.

  1. High resolution laser beam induced current images under trichromatic laser radiation: approximation to the solar irradiation.

    PubMed

    Navas, F J; Alcántara, R; Fernández-Lorenzo, C; Martín-Calleja, J

    2010-03-01

    A laser beam induced current (LBIC) map of a photoactive surface is a very useful tool when it is necessary to study the spatial variability of properties such as photoconverter efficiency or factors connected with the recombination of carriers. Obtaining high spatial resolution LBIC maps involves irradiating the photoactive surface with a photonic beam with Gaussian power distribution and with a low dispersion coefficient. Laser emission fulfils these characteristics, but against it is the fact that it is highly monochromatic and therefore has a spectral distribution different to solar emissions. This work presents an instrumental system and procedure to obtain high spatial resolution LBIC maps in conditions approximating solar irradiation. The methodology developed consists of a trichromatic irradiation system based on three sources of laser excitation with emission in the red, green, and blue zones of the electromagnetic spectrum. The relative irradiation powers are determined by either solar spectrum distribution or Planck's emission formula which provides information approximate to the behavior of the system if it were under solar irradiation. In turn, an algorithm and a procedure have been developed to be able to form images based on the scans performed by the three lasers, providing information about the photoconverter efficiency of photovoltaic devices under the irradiation conditions used. This system has been checked with three photosensitive devices based on three different technologies: a commercial silicon photodiode, a commercial photoresistor, and a dye-sensitized solar cell. These devices make it possible to check how the superficial quantum efficiency has areas dependent upon the excitation wavelength while it has been possible to measure global incident photon-to-current efficiency values approximating those that would be obtained under irradiation conditions with sunlight.

  2. Stress-induced waveguides in Nd:YAG by simultaneous double-beam irradiation with femtosecond pulses

    NASA Astrophysics Data System (ADS)

    Castillo, Gabriel R.; Romero, Carolina; Lifante, Ginés; Jaque, Daniel; Chen, Feng; Varela, Óscar; García-García, Enrique; Méndez, Cruz; Camacho-López, Santiago; Vázquez de Aldana, Javier R.

    2016-01-01

    We report on the fabrication of stress-induced waveguides in Nd:YAG (neodymium doped yttrium aluminum garnet, Nd:Y3Al5O12) by simultaneous double-beam irradiation with femtosecond laser pulses. An interferometer was used to generate two femtosecond laser beams that, focused with certain lateral separation inside the crystal, produced two parallel damage tracks with a single scan. The propagation of the mechanical waves simultaneously created in both focal spots produced a highly symmetrical stress field that is clearly revealed in micro-luminescence maps. The optical properties of the double-beam waveguides are studied and compared to those of single-beam irradiation, showing relevant differences. The creation of more symmetric stress patterns and a slight reduction of propagation losses are explained in terms of the fact that simultaneous inscription allows for a drastic reduction in the magnitude of "incubation" effects related to the existence of pre-damaged states.

  3. ENDOR-Induced EPR of Disordered Systems: Application to X-Irradiated Alanine.

    PubMed

    Kusakovskij, Jevgenij; Maes, Kwinten; Callens, Freddy; Vrielinck, Henk

    2018-02-15

    The electron paramagnetic resonance (EPR) spectra of radiation-induced radicals in organic solids are generally composed of multiple components that largely overlap due to their similar weak g anisotropy and a large number of hyperfine (HF) interactions. Such properties make these systems difficult to study using standard cw EPR spectroscopy even in single crystals. Electron-nuclear double-resonance (ENDOR) spectroscopy is a powerful and widely used complementary technique. In particular, ENDOR-induced EPR (EIE) experiments are useful for separating the overlapping contributions. In the present work, these techniques were employed to study the EPR spectrum of stable radicals in X-irradiated alanine, which is widely used in dosimetric applications. The principal values of all major proton HF interactions of the dominant radicals were determined by analyzing the magnetic field dependence of the ENDOR spectrum at 50 K, where the rotation of methyl groups is frozen. Accurate simulations of the EPR spectrum were performed after the major components were separated using an EIE analysis. As a result, new evidence in favor of the model of the second dominant radical was obtained.

  4. MASM, a Matrine Derivative, Offers Radioprotection by Modulating Lethal Total-Body Irradiation-Induced Multiple Signaling Pathways in Wistar Rats.

    PubMed

    Li, Jianzhong; Xu, Jing; Lu, Yiming; Qiu, Lei; Xu, Weiheng; Lu, Bin; Hu, Zhenlin; Chu, Zhiyong; Chai, Yifeng; Zhang, Junping

    2016-05-17

    Matrine is an alkaloid extracted from Sophora flavescens Ait and has many biological activities, such as anti-inflammatory, antitumor, anti-fibrosis, and immunosuppressive properties. In our previous studies, the matrine derivative MASM was synthesized and exhibited potent inhibitory activity against liver fibrosis. In this study, we mainly investigated its protection against lethal total-body irradiation (TBI) in rats. Administration of MASM reduced the radiation sickness characteristics and increased the 30-day survival of rats before or after lethal TBI. Ultrastructural observation illustrated that pretreatment of rats with MASM significantly attenuated the TBI-induced morphological changes in the different organs of irradiated rats. Gene expression profiles revealed that pretreatment with MASM had a dramatic effect on gene expression changes caused by TBI. Pretreatment with MASM prevented differential expression of 53% (765 genes) of 1445 differentially expressed genes induced by TBI. Pathway enrichment analysis indicated that these genes were mainly involved in a total of 21 pathways, such as metabolic pathways, pathways in cancer, and mitogen-activated protein kinase (MAPK) pathways. Our data indicated that pretreatment of rats with MASM modulated these pathways induced by TBI, suggesting that the pretreatment with MASM might provide the protective effects on lethal TBI mainly or partially through the modulation of these pathways, such as multiple MAPK pathways. Therefore, MASM has the potential to be used as an effective therapeutic or radioprotective agent to minimize irradiation damages and in combination with radiotherapy to improve the efficacy of cancer therapy.

  5. XAS and XMCD studies of magnetic properties modifications of Pt/Co/Au and Pt/Co/Pt trilayers induced by Ga⁺ ions irradiation.

    PubMed

    Mazalski, Piotr; Sveklo, Iosif; Kurant, Zbigniew; Ollefs, Katharina; Rogalev, Andrei; Wilhelm, Fabrice; Fassbender, Juergen; Baczewski, Lech Tomasz; Wawro, Andrzej; Maziewski, Andrzej

    2015-05-01

    Magnetic and magneto-optical properties of Pt/Co/Au and Pt/Co/Pt trilayers subjected to 30 keV Ga(+) ion irradiation are compared. In two-dimensional maps of these properties as a function of cobalt thickness and ion fluence, two branches with perpendicular magnetic anisotropy (PMA) for Pt/Co/Pt trilayers are well distinguished. The replacement of the Pt capping layer with Au results in the two branches still being visible but the in-plane anisotropy for the low-fluence branch is suppressed whereas the high-fluence branch displays PMA. The X-ray absorption spectra and X-ray magnetic circular dichroism (XMCD) spectra are discussed and compared with non-irradiated reference samples. The changes of their shapes and peak amplitude, particularly for the high-fluence branch, are related to the modifications of the local environment of Co(Pt) atoms and the etching effects induced by ion irradiation. Additionally, in irradiated trilayers the XMCD measurements at the Pt L2,3-edge reveal an increase of the magnetic moment induced in Pt atoms.

  6. Molecular response to phototoxic stress of UVB-irradiated ketoprofen through arresting cell cycle in G2/M phase and inducing apoptosis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu Shicheng; Mizu, Hideo; Yamauchi, Hitoshi

    The phototoxicity of ketoprofen (KP), a non-steroidal anti-inflammatory drug, has recently attracted considerable attention, because it is photolabile and undergoes degradation when irradiated by sunlight to induce various skin diseases. The present study shows that combination of UVB irradiation with KP induced the cytotoxicity and suppressed DNA synthesis in HaCaT cells in a concentration-dependent manner. UVB-irradiated KP inhibited the cell growth and induced G2/M cell cycle arrest by modulating the levels of cdc2, cyclin B1, Chk1, Tyr15-phosphorylated cdc2 and p21. It also provoked a striking accumulation of cyclin B1-cdc2-p21 complexes, concomitantly with an increase in the levels of Tyr15-phosphorylated cdc2more » and p21 protein. The presence of KP accentuated the apoptotic response to UVB radiation in HaCaT cells as evidenced by DAPI staining. The apoptotic process was associated with activation of caspase-9, caspase-3 and cleavage of PARP, and this activation could be prevented by a specific caspase-3 inhibitor. Taken together, our results suggest that KP-photoinduced apoptosis may be a useful approach to reduce or prevent skin carcinogenesis.« less

  7. Effects of carotenoids on damage of biological lipids induced by gamma irradiation

    NASA Astrophysics Data System (ADS)

    Saito, Takeshi; Fujii, Noriko

    2014-05-01

    Carotenoids are considered to be involved in the radioresistant mechanisms of radioresistant bacteria. In these bacterial cells, carotenoids are present in biological lipids, and therefore may be related to the radiation-induced damage of lipids. However, only limited data are available for the role of carotenoids in such damage. In this study, we irradiated an α-linolenic acid-benzene solution with gamma rays and analyzed the resulting oxidative degradation and peroxidation damage in the presence or absence of two typical carotenoids: β-carotene and astaxanthin. The analyses revealed that oxidative degradation and peroxidation of α-linolenic acid, as evaluated by the amount of malondialdehyde and conjugated diene formed, respectively, increased in a dose-dependent manner. Moreover, 8.5×10-3 M β-carotene inhibited gamma radiation-induced oxidative degradation of α-linolenic acid, whereas 5.0×10-5 and 5.0×10-6 M β-carotene, and 5.0×10-7 and 5.0×10-8 M astaxanthin promoted degradation. In contrast, neither β-carotene nor astaxanthin affected peroxidation of α-linolenic acid. These results suggest that an optimum concentration of carotenoids in radioresistant bacteria protects biological lipid structures from radiation-induced damage.

  8. Investigation of Oxygen Diffusion in Irradiated UO2 with MD Simulation

    NASA Astrophysics Data System (ADS)

    Günay, Seçkin D.

    2016-11-01

    In this study, irradiated UO2 is analyzed by atomistic simulation method to obtain diffusion coefficient of oxygen ions. For this purpose, a couple of molecular dynamics (MD) supercells containing Frenkel, Schottky, vacancy and interstitial types for both anion and cation defects is constructed individually. Each of their contribution is used to calculate the total oxygen diffusion for both intrinsic and extrinsic ranges. The results display that irradiation-induced defects contribute the most to the overall oxygen diffusion at temperatures below 800-1,200 K. This result is quite sensible because experimental data shows that, from room temperature to about 1,500 K, irradiation-induced swelling decreases and irradiated UO2 lattice parameter is gradually recovered because defects annihilate each other. Another point is that, concentration of defects enhances the irradiation-induced oxygen diffusion. Irradiation type also has the similar effect, namely oxygen diffusion in crystals irradiated with α-particles is more than the crystals irradiated with neutrons. Dynamic Frenkel defects dominate the oxygen diffusion data above 1,500—1,800 K. In all these temperature ranges, thermally induced Frenkel defects make no significant contribution to overall oxygen diffusion.

  9. Low energy electron irradiation induced carbon etching: Triggering carbon film reacting with oxygen from SiO{sub 2} substrate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Cheng; Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060; Wang, Chao, E-mail: cwang367@szu.edu.cn, E-mail: dfdiao@szu.edu.cn

    2016-08-01

    We report low-energy (50–200 eV) electron irradiation induced etching of thin carbon films on a SiO{sub 2} substrate. The etching mechanism was interpreted that electron irradiation stimulated the dissociation of the carbon film and SiO{sub 2}, and then triggered the carbon film reacting with oxygen from the SiO{sub 2} substrate. A requirement for triggering the etching of the carbon film is that the incident electron penetrates through the whole carbon film, which is related to both irradiation energy and film thickness. This study provides a convenient electron-assisted etching with the precursor substrate, which sheds light on an efficient pathway to themore » fabrication of nanodevices and nanosurfaces.« less

  10. The Association between Dust Storms and Daily Non-Accidental Mortality in the United States, 1993–2005

    PubMed Central

    Crooks, James Lewis; Cascio, Wayne E.; Percy, Madelyn S.; Reyes, Jeanette; Neas, Lucas M.; Hilborn, Elizabeth D.

    2016-01-01

    Background: The impact of dust storms on human health has been studied in the context of Asian, Saharan, Arabian, and Australian storms, but there has been no recent population-level epidemiological research on the dust storms in North America. The relevance of dust storms to public health is likely to increase as extreme weather events are predicted to become more frequent with anticipated changes in climate through the 21st century. Objectives: We examined the association between dust storms and county-level non-accidental mortality in the United States from 1993 through 2005. Methods: Dust storm incidence data, including date and approximate location, are taken from the U.S. National Weather Service storm database. County-level mortality data for the years 1993–2005 were acquired from the National Center for Health Statistics. Distributed lag conditional logistic regression models under a time-stratified case-crossover design were used to study the relationship between dust storms and daily mortality counts over the whole United States and in Arizona and California specifically. End points included total non-accidental mortality and three mortality subgroups (cardiovascular, respiratory, and other non-accidental). Results: We estimated that for the United States as a whole, total non-accidental mortality increased by 7.4% (95% CI: 1.6, 13.5; p = 0.011) and 6.7% (95% CI: 1.1, 12.6; p = 0.018) at 2- and 3-day lags, respectively, and by an average of 2.7% (95% CI: 0.4, 5.1; p = 0.023) over lags 0–5 compared with referent days. Significant associations with non-accidental mortality were estimated for California (lag 2 and 0–5 day) and Arizona (lag 3), for cardiovascular mortality in the United States (lag 2) and Arizona (lag 3), and for other non-accidental mortality in California (lags 1–3 and 0–5). Conclusions: Dust storms are associated with increases in lagged non-accidental and cardiovascular mortality. Citation: Crooks JL, Cascio WE, Percy MS, Reyes

  11. Anti-inflammatory effect of linear polarized infrared irradiation on interleukin-1beta-induced chemokine production in MH7A rheumatoid synovial cells.

    PubMed

    Shibata, Yasuko; Ogura, Naomi; Yamashiro, Keisuke; Takashiba, Shogo; Kondoh, Toshirou; Miyazawa, Keiji; Matsui, Masaru; Abiko, Yoshimitsu

    2005-12-01

    We examined the anti-inflammatory effect of infrared linear polarized light irradiation on the MH7A rheumatoid fibroblast-like synoviocytes (FLS) stimulated with the proinflammatory cytokine interleukin (IL)-1beta. Expression of messenger ribonucleic acids (mRNAs) encoding IL-8, RANTES (regulated upon activation, normal T cell expressed and secreted), growth-related gene alpha (GROalpha), and macrophage inflammatory protein-1alpha (MIP1alpha) was measured using real-time reverse transcription polymerase chain reaction, and the secreted proteins were measured in the conditioned media using enzyme-linked immunosorbent assays. We found that irradiation with linear polarized infrared light suppressed IL-1beta-induced expression of IL-8 mRNA and, correspondingly, the synthesis and release of IL-8 protein in MH7A cells. This anti-inflammatory effect was equivalent to that obtained with the glucocorticoid dexamethasone. Likewise, irradiation suppressed the IL-1beta-induced expression of RANTES and GROalpha mRNA. These results suggest that the irradiation of the areas around the articular surfaces of joints affected by rheumatoid arthritis (RA) using linear polarized light may represent a useful new approach to treatment.

  12. Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gualde, N.; Goodwin, J.S.

    1984-04-01

    Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less (/sup 3/H)thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced (/sup 3/H)thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), andmore » OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset.« less

  13. Measurements of near-ultimate strength for multiwalled carbon nanotubes and irradiation-induced crosslinking improvements.

    PubMed

    Peng, Bei; Locascio, Mark; Zapol, Peter; Li, Shuyou; Mielke, Steven L; Schatz, George C; Espinosa, Horacio D

    2008-10-01

    The excellent mechanical properties of carbon nanotubes are being exploited in a growing number of applications from ballistic armour to nanoelectronics. However, measurements of these properties have not achieved the values predicted by theory due to a combination of artifacts introduced during sample preparation and inadequate measurements. Here we report multiwalled carbon nanotubes with a mean fracture strength >100 GPa, which exceeds earlier observations by a factor of approximately three. These results are in excellent agreement with quantum-mechanical estimates for nanotubes containing only an occasional vacancy defect, and are approximately 80% of the values expected for defect-free tubes. This performance is made possible by omitting chemical treatments from the sample preparation process, thus avoiding the formation of defects. High-resolution imaging was used to directly determine the number of fractured shells and the chirality of the outer shell. Electron irradiation at 200 keV for 10, 100 and 1,800 s led to improvements in the maximum sustainable loads by factors of 2.4, 7.9 and 11.6 compared with non-irradiated samples of similar diameter. This effect is attributed to crosslinking between the shells. Computer simulations also illustrate the effects of various irradiation-induced crosslinking defects on load sharing between the shells.

  14. Measurements of near-ultimate strength for multiwalled carbon nanotubes and irradiation-induced crosslinking improvements.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peng, B.; Locascio, M.; Zapol, P.

    2008-01-01

    The excellent mechanical properties of carbon nanotubes are being exploited in a growing number of applications from ballistic armour to nanoelectronics. However, measurements of these properties have not achieved the values predicted by theory due to a combination of artifacts introduced during sample preparation and inadequate measurements. Here we report multiwalled carbon nanotubes with a mean fracture strength >100 GPa, which exceeds earlier observations by a factor of approximately three. These results are in excellent agreement with quantum-mechanical estimates for nanotubes containing only an occasional vacancy defect, and are {approx}80% of the values expected for defect-free tubes. This performance ismore » made possible by omitting chemical treatments from the sample preparation process, thus avoiding the formation of defects. High-resolution imaging was used to directly determine the number of fractured shells and the chirality of the outer shell. Electron irradiation at 200 keV for 10, 100 and 1,800 s led to improvements in the maximum sustainable loads by factors of 2.4, 7.9 and 11.6 compared with non-irradiated samples of similar diameter. This effect is attributed to crosslinking between the shells. Computer simulations also illustrate the effects of various irradiation-induced crosslinking defects on load sharing between the shells.« less

  15. Combination therapy for radiation-induced bone marrow aplasia in nonhuman primates using synthokine SC-55494 and recombinant human granulocyte colony-stimulating factor.

    PubMed

    MacVittie, T J; Farese, A M; Herodin, F; Grab, L B; Baum, C M; McKearn, J P

    1996-05-15

    Combination cytokine therapy continues to be evaluated in an effort to stimulate multilineage hematopoietic reconstitution after bone marrow myelosuppression. This study evaluated the efficacy of combination therapy with the synthetic interleukin-3 receptor agonist, Synthokine-SC55494, and recombinant methionyl human granulocyte colony-stimulating factor (rhG-CSF) on platelet and neutrophil recovery in nonhuman primates exposed to total body 700 cGy 60Co gamma radiation. After irradiation on day (d) 0, cohorts of animals subcutaneously received single-agent protocols of either human serum albumin (HSA; every day [QD], 15 micrograms/kg/d, n = 10), Synthokine (twice daily [BID], 100, micrograms/kg/d, n = 15), rhG-CSF (QD, 10 micrograms/kg/d, n = 5), or a combination of Synthokine and rhG-CSF (BID, 100 and 10 micrograms/kg/d, respectively, n = 5) for 23 days beginning on d1. Complete blood counts were monitored for 60 days postirradiation and the durations of neutropenia (absolute neutrophil count < 500/microL) and thrombocytopenia (platelet count < 20,000/microL) were assessed. Animals were provided clinical support in the form of antibiotics, fresh irradiated whole blood, and fluids. All cytokine protocols significantly (P < .05) reduced the duration thrombocytopenia versus the HSA-treated animals. Only the combination protocol of Synthokine + rhG-CSF and rhG-CSF alone significantly shortened the period neutropenia (P < .05). The combined Synthokine/rhG-CSF protocol significantly improved platelet nadir versus Synthokine alone and HSA controls and neutrophil nadir versus rhG-CSF alone and HSA controls. All cytokine protocols decreased the time to recovery to preirradiation neutrophil and platelet values. The Synthokine/rhG-CSF protocol also reduced the transfusion requirements per treatment group to 0 among 5 animals as compared with 2 among 5 animals for Synthokine alone, 8 among 5 animals for rhG-CSF, and 17 among 10 animals for HSA. These data showed that the

  16. Determinants of Suicide and Accidental or Violent Death in the Australian HIV Observational Database

    PubMed Central

    McManus, Hamish; Petoumenos, Kathy; Franic, Teo; Kelly, Mark D.; Watson, Jo; O’Connor, Catherine C.; Jeanes, Mark; Hoy, Jennifer; Cooper, David A.; Law, Matthew G.

    2014-01-01

    Background Rates of suicide and accidental or violent death remain high in HIV-positive populations despite significantly improved prognosis since the introduction of cART. Methods We conducted a nested case-control study of suicide and accidental or violent death in the Australian HIV Observational Database (AHOD) between January 1999 and March 2012. For each case, 2 controls were matched by clinic, age, sex, mode of exposure and HIV-positive date to adjust for potential confounding by these covariates. Risk of suicide and accidental or violent death was estimated using conditional logistic regression. Results We included 27 cases (17 suicide and 10 violent/accidental death) and 54 controls. All cases were men who have sex with men (MSM) or MSM/ injecting drug use (IDU) mode of exposure. Increased risk was associated with unemployment (Odds Ratio (OR) 5.86, 95% CI: 1.69–20.37), living alone (OR 3.26, 95% CI: 1.06–10.07), suicidal ideation (OR 6.55, 95% CI: 1.70–25.21), and >2 psychiatric/cognitive risk factors (OR 4.99, 95% CI: 1.17–30.65). CD4 cell count of >500 cells/µL (OR 0.25, 95% CI: 0.07–0.87) and HIV-positive date ≥1990 (1990–1999 (OR 0.31, 95% CI: 0.11–0.89), post-2000 (OR 0.08, 95% CI: 0.01–0.84)) were associated with decreased risk. CD4 cell count ≥500 cells/µL remained a significant predictor of reduced risk (OR 0.15, 95% CI: 0.03–0.70) in a multivariate model adjusted for employment status, accommodation status and HIV-positive date. Conclusions After adjustment for psychosocial factors, the immunological status of HIV-positive patients contributed to the risk of suicide and accidental or violent death. The number of psychiatric/cognitive diagnoses contributed to the level of risk but many psychosocial factors were not individually significant. These findings indicate a complex interplay of factors associated with risk of suicide and accidental or violent death. PMID:24586519

  17. Crystal plasticity modeling of irradiation growth in Zircaloy-2

    DOE PAGES

    Patra, Anirban; Tome, Carlos; Golubov, Stanislav I.

    2017-05-10

    A reaction-diffusion based mean field rate theory model is implemented in the viscoplastic self-consistent (VPSC) crystal plasticity framework to simulate irradiation growth in hcp Zr and its alloys. A novel scheme is proposed to model the evolution (both number density and radius) of irradiation-induced dislocation loops that can be informed directly from experimental data of dislocation density evolution during irradiation. This framework is used to predict the irradiation growth behavior of cold-worked Zircaloy-2 and trends compared to available experimental data. The role of internal stresses in inducing irradiation creep is discussed. Effects of grain size, texture, and external stress onmore » the coupled irradiation growth and creep behavior are also studied.« less

  18. Crystal plasticity modeling of irradiation growth in Zircaloy-2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patra, Anirban; Tome, Carlos; Golubov, Stanislav I.

    A reaction-diffusion based mean field rate theory model is implemented in the viscoplastic self-consistent (VPSC) crystal plasticity framework to simulate irradiation growth in hcp Zr and its alloys. A novel scheme is proposed to model the evolution (both number density and radius) of irradiation-induced dislocation loops that can be informed directly from experimental data of dislocation density evolution during irradiation. This framework is used to predict the irradiation growth behavior of cold-worked Zircaloy-2 and trends compared to available experimental data. The role of internal stresses in inducing irradiation creep is discussed. Effects of grain size, texture, and external stress onmore » the coupled irradiation growth and creep behavior are also studied.« less

  19. Single cell analysis of low-power laser irradiation-induced activation of signaling pathway in cell proliferation

    NASA Astrophysics Data System (ADS)

    Xing, Da; Gao, Xuejuan

    2007-02-01

    Low-power laser irradiation (LPLI) has been shown to promote cell proliferation in various cell types, yet the mechanism of which has not been fully clarified. Investigating the signaling pathways involved in the laser irradiation is important for understanding these processes. The small G protein Ras works as a binary switch in many important intracellular signaling pathways and, therefore, has been one of the focal targets of signal-transduction investigations and drug development. The Ras/Raf/MEK/ERK (extracellular-signal-regulated kinase) signaling pathway is a network that governs proliferation, differentiation and cell survival. Recent studies suggest that Ras/Raf signaling pathway is involved in the LPLI-induced cell proliferation. On the other hand, Protein kinase Cs (PKCs), the Ca 2+ activated, phospholipid-dependent serine/threonine protein kinases, have been recently presumed to be involved in the regulation of cell proliferation induced by LPLI. In this report, to monitor the direct activations of Ras and PKCs after LPLI treatment in living cells in real time, Raichu-Ras reporter and C kinase activity reporter (CKAR) were utilized, both of which were constructed based on fluorescence resonance energy transfer (FRET) technique. The direct activation of Ras is predominantly initiated from the different microdomains of the plasma membrane. The results are monitored during cell proliferation induced by LPLI (0.8 J/cm2) in serum-starved COS-7 cells expressing Raichu-Ras reporter using FRET imaging on laser scanning confocal microscope. Furthermore, the increasing activation of PKCs is also monitored during cell proliferation induced by LPLI (0.8 J/cm2) in serum-starved human lung adenocarcinoma cells (ASTC-a-1) expressing CKAR reporter using the similar way. Taken together, the dynamic increases of H-Ras and PKCs activities are observed during the processes of cell proliferation induced by LPLI.

  20. Correlation of proton irradiation induced threshold voltage shifts to deep level traps in AlGaN/GaN heterostructures

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Cardwell, D.; Sasikumar, A.; Kyle, E. C. H.; Chen, J.; Zhang, E. X.; Fleetwood, D. M.; Schrimpf, R. D.; Speck, J. S.; Arehart, A. R.; Ringel, S. A.

    2016-04-01

    The impact of proton irradiation on the threshold voltage (VT) of AlGaN/GaN heterostructures is systematically investigated to enhance the understanding of a primary component of the degradation of irradiated high electron mobility transistors. The value of VT was found to increase monotonically as a function of 1.8 MeV proton fluence in a sub-linear manner reaching 0.63 V at a fluence of 1 × 1014 cm-2. Silvaco Atlas simulations of VT shifts caused by GaN buffer traps using experimentally measured introduction rates, and energy levels closely match the experimental results. Different buffer designs lead to different VT dependences on proton irradiation, confirming that deep, acceptor-like defects in the GaN buffer are primarily responsible for the observed VT shifts. The proton irradiation induced VT shifts are found to depend on the barrier thickness in a linear fashion; thus, scaling the barrier thickness could be an effective way to reduce such degradation.

  1. Low dose irradiation facilitates hepatocellular carcinoma genesis involving HULC.

    PubMed

    Li, Yuan; Ge, Chang; Feng, Guoxing; Xiao, Huiwen; Dong, Jiali; Zhu, Changchun; Jiang, Mian; Cui, Ming; Fan, Saijun

    2018-03-24

    Irradiation exposure positive correlates with tumor formation, such as breast cancer and lung cancer. However, whether low dose irradiation induces hepatocarcinogenesis and the underlying mechanism remain poorly defined. In the present study, we reported that low dose irradiation facilitated the proliferation of hepatocyte through up-regulating HULC in vitro and in vivo. Low dose irradiation exposure elevated HULC expression level in hepatocyte. Deletion of heightened HULC erased the cells growth accelerated following low dose irradiation exposure. CDKN1, the neighbor gene of HULC, was down-regulated by overexpression of HULC following low dose irradiation exposure via complementary base pairing, resulting in promoting cell cycle process. Thus, our findings provide new insights into the mechanism of low dose irradiation-induced hepatocarcinogenesis through HULC/CDKN1 signaling, and shed light on the potential risk of low dose irradiation for the development of hepatocellular carcinoma in pre-clinical settings. © 2018 Wiley Periodicals, Inc.

  2. Incidence and characteristics of accidental falls in hospitalizations

    PubMed Central

    Kobayashi, Kazuyoshi; Imagama, Shiro; Inagaki, Yuko; Suzuki, Yusuke; Ando, Kei; Nishida, Yoshihiro; Nagao, Yoshimasa; Ishiguro, Naoki

    2017-01-01

    ABSTRACT Aging of the patient population has led to increased occurrence of accidental falls in acute care settings. The aim of this study is to survey the annual occurrence of falls in a university hospital, and to examine procedures to prevent fall. A total of 49,059 inpatients were admitted to our hospital from April 2015 to March 2016. A fall assessment scale was developed to estimate the risk of fall at admission. Data on falls were obtained from the hospital incident reporting system. There were fall-related incidents in 826 patients (1.7%). Most falls occurred in hospital rooms (67%). Adverse events occurred in 101 patients who fell (12%) and were significantly more frequent in patients aged ≥80 years old and in those wearing slippers. The incidence of falls was also significantly higher in patients in the highest risk group. These results support the validity of the risk assessment scale for predicting accidental falls in an acute treatment setting. The findings also clarify the demographic and environmental factors and consequences associated with fall. These results of the study could provide important information for designing effective interventions to prevent fall in elderly patients. PMID:28878434

  3. Observation and analysis on skin cancer induced by UVB irradiation using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Wang, Yunxia; Wu, Shulian; Li, Hui; Zheng, Xiaoxiao

    2014-09-01

    Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the prevalent skin cancers, which have a quite high incidence in the white race. In recent years, however, their incidences have been increasing in the yellow race, resulting in a great threat to the public health. According to researches, chronics UVB irradiation (280nm~320nm) is the major culprit of skin cancer in humans. In our study, the model of UVB induced skin cancer was established firstly. Optical coherence tomography (OCT) combined with the histopathology was exploited to monitor the morphologic and histological changes of the process of UVB induced skin cancer. Meanwhile, this canceration process was systematically studied and analyzed from the perspective of tissue optics. The attenuation coefficient (μt) has a rising trend in the epidermis, but which shows a downward trend in the dermis. The results are conducive to understand the process of UVB-induced skin cancer and further be able to provide a reference for medical researchers.

  4. Antioxidative activity and growth regulation of Brassicaceae induced by oxygen radical irradiation

    NASA Astrophysics Data System (ADS)

    Hayashi, Nobuya; Ono, Reoto; Shiratani, Masaharu; Yonesu, Akira

    2015-06-01

    The growth regulation characteristics of plants are investigated when plant seeds are irradiated with atmospheric discharge plasma. Enhancement of the germination and lengths of the stem and root of plants are observed after seeding. The total length of the stem and root increases approximately 1.6 times after a cultivation period of 72 h. The growth regulation effect is found to be maintained for 80 h of cultivation after seeding. The growth regulation originates from the change in the antioxidative activity of plant cells induced by active oxygen species generated in the oxygen plasma, which leads to the production of growth factor in plants.

  5. Effect of laser irradiation on the early-stage seed formation of laser-induced submicrometer-scale silica spheres

    NASA Astrophysics Data System (ADS)

    Kim, H. J.; Ha, S. Y.; Hong, Y. J.; Nam, S.; Oh, S. Y.; Lim, C.

    2014-04-01

    We describe the effect of irradiation on the early-stage seed formation of submicrometer-scale (SS) SiO2 spheres by a laser-induced process. A quartz cell containing chemical reagents was exposed to a pulsed laser (Nd:YAG, 532 nm) tuned to various energy densities, while SiO2 SS spheres are synthesized in the quartz cell by the Stöber, Fink, and Bohn method. Higher laser energy densities typically produce wider size distributions. In particular, bidisperse SiO2 spheres were obtained when the laser energy density was 1.15 J/cm2. The size distributions were widest with 1.15 J/cm2 and narrowest with 0.33 J/cm2 laser energy density. However, the compositions of the SiO2 SS spheres were not affected by laser irradiation, and we observed by the energy-dispersive X-ray spectroscopy that the compositions of the irradiated and nonirradiated SiO2 SS spheres were the same.

  6. Young and juvenile chimpanzees' (Pan troglodytes) reactions to intentional versus accidental and inadvertent actions.

    PubMed

    Povinelli, D J; Perilloux, H K; Reaux, J E; Bierschwale, D T

    1998-02-01

    Chimpanzees were tested for their ability to discriminate between accidental/inadvertent and intentional actions with equivalent adverse consequences. Subjects were first trained to `point' to human trainers in order to receive food rewards. In Experiment 1, six 5-year-old subjects were alternately presented with two unfamiliar human actors. In condition 1, each actor either started to hand a cup of juice to the trainer but then pulled it back and intentionally poured it onto the floor, or accidentally spilled it while handing it to the trainer. In condition 2, the actors either accidentally spilled it as above, or aggressively threw the juice onto the floor. The subjects were then presented with both actors and were allowed to choose between them. In Experiment 2, seven 6-7-year-old chimpanzees were confronted with unfamiliar actors who either (a) intentionally withheld and consumed food intended for the subjects, (b) attempted to hand the intended food to the subjects but were victimized by a third party who consumed the food, or (c) always succeeded in delivering the food to the subjects. In general, the subjects showed little evidence of using the accidental/inadvertent versus intentional distinction in their choices between the actors, although they did display some evidence of favoring the actor involved in the most passive role in both conditions in Experiment 1.

  7. Irradiation effects in monazite-(Ce) and zircon: Raman and photoluminescence study of Au-irradiated FIB foils

    NASA Astrophysics Data System (ADS)

    Nasdala, Lutz; Akhmadaliev, Shavkat; Artac, Andreas; Chanmuang N., Chutimun; Habler, Gerlinde; Lenz, Christoph

    2018-05-01

    Lamellae of 1.5 µm thickness, prepared from well-crystallised monazite-(Ce) and zircon samples using the focused-ion-beam technique, were subjected to triple irradiation with 1 MeV Au+ ions (15.6% of the respective total fluence), 4 MeV Au2+ ions (21.9%) and 10 MeV Au3+ ions (62.5%). Total irradiation fluences were varied in the range 4.5 × 1012 - 1.2 × 1014 ions/cm2. The highest fluence resulted in amorphisation of both minerals; all other irradiations (i.e. up to 4.5 × 1013 ions/cm2) resulted in moderate to severe damage. Lamellae were subjected to Raman and laser-induced photoluminescence analysis, in order to provide a means of quantifying irradiation effects using these two micro-spectroscopy techniques. Based on extensive Monte Carlo calculations and subsequent defect-density estimates, irradiation-induced spectroscopic changes are compared with those of naturally self-irradiated samples. The finding that ion irradiation of monazite-(Ce) may cause severe damage or even amorphisation, is in apparent contrast to the general observation that naturally self-irradiated monazite-(Ce) does not become metamict (i.e. irradiation-amorphised), in spite of high self-irradiation doses. This is predominantly assigned to the continuous low-temperature damage annealing undergone by this mineral; other possible causes are discussed. According to cautious estimates, monazite-(Ce) samples of Mesoproterozoic to Cretaceous ages have stored only about 1% of the total damage experienced. In contrast, damage in ion-irradiated and naturally self-irradiated zircon is on the same order; reasons for the observed slight differences are discussed. We may assess that in zircon, alpha decays create significantly less than 103 Frenkel-type defect pairs per event, which is much lower than previous estimates. Amorphisation occurs at defect densities of about 0.10 dpa (displacements per lattice atom).

  8. Unraveling irradiation induced grain growth with in situ transmission electron microscopy and coordinated modeling

    DOE PAGES

    Bufford, D. C.; Abdeljawad, F. F.; Foiles, S. M.; ...

    2015-11-09

    Here, nanostructuring has been proposed as a method to enhance radiation tolerance, but many metallic systems are rejected due to significant concerns regarding long term grain boundary and interface stability. This work utilized recent advancements in transmission electron microscopy (TEM) to quantitatively characterize the grain size, texture, and individual grain boundary character in a nanocrystalline gold model system before and after in situ TEM ion irradiation with 10 MeV Si. The initial experimental measurements were fed into a mesoscale phase field model, which incorporates the role of irradiation-induced thermal events on boundary properties, to directly compare the observed and simulatedmore » grain growth with varied parameters. The observed microstructure evolution deviated subtly from previously reported normal grain growth in which some boundaries remained essentially static. In broader terms, the combined experimental and modeling techniques presented herein provide future avenues to enhance quantification and prediction of the thermal, mechanical, or radiation stability of grain boundaries in nanostructured crystalline systems.« less

  9. Ion irradiation to simulate neutron irradiation in model graphites: Consequences for nuclear graphite

    NASA Astrophysics Data System (ADS)

    Galy, N.; Toulhoat, N.; Moncoffre, N.; Pipon, Y.; Bérerd, N.; Ammar, M. R.; Simon, P.; Deldicque, D.; Sainsot, P.

    2017-10-01

    Due to its excellent moderator and reflector qualities, graphite was used in CO2-cooled nuclear reactors such as UNGG (Uranium Naturel-Graphite-Gaz). Neutron irradiation of graphite resulted in the production of 14C which is a key issue radionuclide for the management of the irradiated graphite waste. In order to elucidate the impact of neutron irradiation on 14C behavior, we carried out a systematic investigation of irradiation and its synergistic effects with temperature in Highly Oriented Pyrolitic Graphite (HOPG) model graphite used to simulate the coke grains of nuclear graphite. We used 13C implantation in order to simulate 14C displaced from its original structural site through recoil. The collision of the impinging neutrons with the graphite matrix carbon atoms induces mainly ballistic damage. However, a part of the recoil carbon atom energy is also transferred to the graphite lattice through electronic excitation. The effects of the different irradiation regimes in synergy with temperature were simulated using ion irradiation by varying Sn(nuclear)/Se(electronic) stopping power. Thus, the samples were irradiated with different ions of different energies. The structure modifications were followed by High Resolution Transmission Electron Microscopy (HRTEM) and Raman microspectrometry. The results show that temperature generally counteracts the disordering effects of irradiation but the achieved reordering level strongly depends on the initial structural state of the graphite matrix. Thus, extrapolating to reactor conditions, for an initially highly disordered structure, irradiation at reactor temperatures (200 - 500 °C) should induce almost no change of the initial structure. On the contrary, when the structure is initially less disordered, there should be a "zoning" of the reordering: In "cold" high flux irradiated zones where the ballistic damage is important, the structure should be poorly reordered; In "hot" low flux irradiated zones where the ballistic

  10. Salidroside protects against premature senescence induced by ultraviolet B irradiation in human dermal fibroblasts.

    PubMed

    Mao, G-X; Xing, W-M; Wen, X-L; Jia, B-B; Yang, Z-X; Wang, Y-Z; Jin, X-Q; Wang, G-F; Yan, J

    2015-06-01

    Salidroside, the predominant component of a Chinese herbal medicine, Rhodiola rosea L., becomes an attractive bio-agent due to its multifunction. Although it is well proposed that this herbal medicine may have photoprotective effect according to the folk hearsay, the direct supportive experimental evidences linking the drug with skin ageing have rarely been reported so far. The study was conducted to investigate the photoprotective role of salidrosdie and its related mechanisms in vitro. First, a premature senescence model induced by UVB irradiation (250 mJ cm(-2)) in human dermal fibroblasts (HDFs) was established, and senescent phenotypes were evaluated by cell morphology, cell proliferation, senescence-associated beta-galactosidase (SA-β-gal) activity and cell cycle distribution. Then the photoprotective effect of salidroside was investigated. Cells were pre-treated with various doses of salidroside (1, 5 and 10 μM) followed by the sublethal dosage of UVB exposure and then were harvested for various detections, including senescence-associated phenotypes and molecules, alteration of oxidative stress, matrix metalloproteinase-1 (MMP-1) secretion and inflammatory response. Pre-treatment of salidroside dose dependently reversed the senescent state of HDFs induced by UVB as evidenced by elevated cell viability, decreased SA-β-gal activity and relieving of G1/G0 cell cycle arrest. UVB-induced increased protein expression of cyclin-dependent kinase (CDK) inhibitors p21(WAF) (1) and p16(INK) (4) was also repressed by salidrosdie treatment in a dose-dependent manner. Meanwhile, the increment of malondialdehyde (MDA) level in UVB-irradiated HDFs was inhibited upon salidroside treatment. Additionally, salidroside significantly attenuated UVB-induced synthesis of MMP-1 as well as the production of IL-6 and TNF-α in HDFs. Our data provided the evidences for the protective role of salidroside against UVB-induced premature senescence in HDFs probably via its anti

  11. Food allergy: practical approach on education and accidental exposure prevention.

    PubMed

    Pádua, I; Moreira, A; Moreira, P; Barros, R

    2016-09-01

    Food allergies are a growing problem and currently the primary treatment of food allergy is avoidance of culprit foods. However, given the lack of information and education and also the ubiquitous nature of allergens, accidental exposures to food allergens are not uncommon. The fear of potential fatal reactions and the need of a proper avoidance leads in most of the cases to the limitation of leisure and social activities. This review aims to be a practical approach on education and accidental exposure prevention regarding activities like shopping, eating out, and travelling. The recommendations are focused especially on proper reading of food labels and the management of the disease, namely in restaurants and airplanes, concerning cross-contact and communication with other stakeholders. The implementation of effective tools is essential to manage food allergy outside home, avoid serious allergic reactions and minimize the disease's impact on individuals' quality of life.

  12. Site specific oxidation of amino acid residues in rat lens γ-crystallin induced by low-dose γ-irradiation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Ingu; Saito, Takeshi; Research Reactor Institute, Kyoto University, Kumatori, Osaka 590-0494

    Although cataracts are a well-known age-related disease, the mechanism of their formation is not well understood. It is currently thought that eye lens proteins become abnormally aggregated, initially causing clumping that scatters the light and interferes with focusing on the retina, and ultimately resulting in a cataract. The abnormal aggregation of lens proteins is considered to be triggered by various post-translational modifications, such as oxidation, deamidation, truncation and isomerization, that occur during the aging process. Such modifications, which are also generated by free radical and reactive oxygen species derived from γ-irradiation, decrease crystallin solubility and lens transparency, and ultimately leadmore » to the development of a cataract. In this study, we irradiated young rat lenses with low-dose γ-rays and extracted the water-soluble and insoluble protein fractions. The water-soluble and water-insoluble lens proteins were digested with trypsin, and the resulting peptides were analyzed by LC-MS. Specific oxidation sites of methionine, cysteine and tryptophan in rat water-soluble and -insoluble γE and γF-crystallin were determined by one-shot analysis. The oxidation sites in rat γE and γF-crystallin resemble those previously identified in γC and γD-crystallin from human age-related cataracts. Our study on modifications of crystallins induced by ionizing irradiation may provide useful information relevant to human senile cataract formation. - Highlights: • Low-dose γ-rays induced oxidation at specific residues in γE- and γF-crystallin. • The number of oxidation sites was higher in insoluble than soluble crystallins. • γ-Irradiation closely mimics the oxidation that occur in senile human cataracts.« less

  13. Ultraviolet B irradiation of the mouse eye induces pigmentation of the skin more strongly than does stress loading, by increasing the levels of prohormone convertase 2 and α-melanocyte-stimulating hormone.

    PubMed

    Hiramoto, K; Yamate, Y; Kobayashi, H; Ishii, M; Sato, E F; Inoue, M

    2013-01-01

    In previous studies, we made the unexpected finding that in mice, ultraviolet (UV)B irradiation of the eye increased the concentration of α-melanocyte-stimulating hormone (α-MSH) in plasma, and systemically stimulated epidermal melanocytes. To compare the extent of the pigmentation induced by social and restraint stress (which activate the hippocampus-pituitary system) with that induced by UVB irradiation. DBA/2 and sham-operated or hypophysectomized DBA/2 mice were subjected to local UVB exposure using a sunlamp directed at the eye, and two types of stress (social and restraint) were imposed. UVB irradiation of the eye or exposure to stress loading both increased the number of Dopa-positive melanocytes in the epidermis, and hypophysectomy strongly inhibited the UVB-induced and stress-induced stimulation of melanocytes. Irradiation of the eye caused a much greater increase in dopamine than did the stress load. Both UVB eye irradiation and stress increased the blood levels of α-MSH and adrenocorticotropic hormone (ACTH). In addition, the increase in plasma α-MSH was greater in animals subjected to UVB eye irradiation than in those subjected to stress loading, whereas the reverse occurred for plasma ACTH. UVB irradiation to the eye and stress loading increased the expression of prohormone convertase (PC)1/3 and PC2 in the pituitary gland. The increase in expression of pituitary PC2 was greater in animals subjected to UVB eye irradiation than to stress, whereas no difference was seen between the two groups for the increase in PC1/3. UVB eye irradiation exerts a stronger effect on pigmentation than stress loading, and is related to increased levels of α-MSH and PC2. © The Author(s). CED © 2012 British Association of Dermatologists.

  14. Electron-beam irradiation induced transformation of Cu2(OH)3NO3 nanoflakes into nanocrystalline CuO

    NASA Astrophysics Data System (ADS)

    Padhi, S. K.; Gottapu, S. N.; Krishna, M. Ghanashyam

    2016-05-01

    The transmission electron microscope electron-beam (TEM e-beam) as a material modification tool has been demonstrated. The material modification is realised in the high-resolution TEM mode (largest condenser aperture, 150 μm, and 200 nm spot size) at a 200 keV beam energy. The Cu2(OH)3NO3 (CHN) nanoflakes used in this study were microwave solution processed that were layered single crystals and radiation sensitive. The single domain CHN flakes disintegrate into a large number of individual CuO crystallites within a 90 s span of time. The sequential bright-field, dark-field, and selected area electron diffraction modes were employed to record the evolved morphology, microstructural changes, and structural transformation that validate CHN modification. High-resolution transmission electron microscopy imaging of e-beam irradiated regions unambiguously supports the growth of CuO nanoparticles (11.8(3.2) nm in diameter). This study demonstrates e-beam irradiation induced CHN depletion, subsequent nucleation and growth of nanocrystalline CuO regions well embedded in the parent burnt porous matrix which can be useful for miniaturized sensing applications. NaBH4 induced room temperature reduction of CHN to elemental Cu and its printability on paper was also demonstrated.The transmission electron microscope electron-beam (TEM e-beam) as a material modification tool has been demonstrated. The material modification is realised in the high-resolution TEM mode (largest condenser aperture, 150 μm, and 200 nm spot size) at a 200 keV beam energy. The Cu2(OH)3NO3 (CHN) nanoflakes used in this study were microwave solution processed that were layered single crystals and radiation sensitive. The single domain CHN flakes disintegrate into a large number of individual CuO crystallites within a 90 s span of time. The sequential bright-field, dark-field, and selected area electron diffraction modes were employed to record the evolved morphology, microstructural changes, and structural

  15. [Change of chart genes expression in small intestines of mouse induced by electromagnetic pulse irradiation].

    PubMed

    Ren, Dongqing; Jin, Juan; Li, Xiaojuan; Zeng, Guiying

    2008-01-01

    To explore the bio-effects of electromagnetic pulse(EMP) on mouse small intestines induced by means of gene chip. Twelve BALB/c mice were randomly assigned to the normal control group and the EMP group with 6 in each group. The EMP group was irradiated with 200 kV/m, 200 pulses EMP. 18 hours after the irradiation, the mice were sacrificed and their jejunum of small intestines were eviscerated. The fluorescent cDNA probes labeled with Cy3 and Cy5 were prepared from RNA extracted from the intestines of the two groups. Probes of the two groups were then hybridized against cDNA gene chip, the fluorescent signals were scanned with a scanner and the results were analyzed by computer. Compared with the control, 56 genes in gene expression profile were altered. The expression levels of 37 genes were up-regulated distinctly while 19 genes were down-regulated significantly. Among the 56 genes, 19 were reported with known or inferred functions, 12 up-regulated genes were catenin alpha 1 (alpha-catenin), ly-6 alloantigen(Ly-6E), fructose-6-phosphate transaminase (GF6P), ribosomal protein S17 (rpS17), small proline-rich protein 2A (Sprr2a), glandular kallikrein27 (GK27), lipoxygenase-3, aldo-keto reductase (Akr1c12), GSG1, amylase 2 (Amy2),elastase 2, p6-5 gene and 7 down-regulated genes were junctional adhesion molecule (Jam), protein arginine methyltransferase (Carm1),NNP-1, 2-5 A synthetase L2,Mlark gene, ATP synthase alpha subunit, uncoupling protein-2 (Ucp2) gene; the other 37 were reported with unknown functions. EMP irradiation could induce specific expressions of some genes in mouse small intestines and most of these genes were up-regulated ones.

  16. Laser induced periodic surface structures formation by nanosecond laser irradiation of poly (ethylene terephthalate) reinforced with Expanded Graphite

    NASA Astrophysics Data System (ADS)

    Rodríguez-Beltrán, René I.; Hernandez, Margarita; Paszkiewicz, Sandra; Szymczyk, Anna; Rosłaniec, Zbigniew; Ezquerra, Tiberio A.; Castillejo, Marta; Moreno, Pablo; Rebollar, Esther

    2018-04-01

    We report on the formation of Laser Induced Periodic Surface Structures in poly (ethylene terephthalate) and poly (ethylene terephthalate)/Expanded Graphite films by laser irradiation with nanosecond pulses at 266 nm. The characterization studies show that the quality of the ripples depends strongly on the irradiation time and fluence and the optimal conditions for obtaining LIPSS are affected by the amount of the expanded graphite present in the film due to the differences in crystallinity, thermal conductivity and thermal diffusivity of the nanocomposites. Physicochemical modifications in the materials were inspected by Raman spectroscopy, the colloidal probe technique and contact angle measurements using different liquids. Results show that there is an increase of the hydrophilicity of the surfaces after laser irradiation together with an increase of the surface free energy and in particular of its polar component. Additionally, the adhesion force estimated by the colloidal probe technique increases after laser nanostructuring.

  17. A tree branch instead of a ligature: an unusual accidental hanging.

    PubMed

    Vadysinghe, Amal Nishantha; Sivasubramanium, Murugupillai; Jayasooriya, Rankothge Pemasiri

    2017-12-01

    A unique case of accidental hanging due to compression of the neck of an adult by the branches of a coffee tree is reported. The decedent was a 42-year-old male who was found dead in a semi prone position on a slope. His neck was lodged in a wedge formed by two branches of a coffee tree, with his legs angled downwards on the slope. Autopsy revealed two friction abrasions located horizontally on either side of the front of the neck, just above the larynx. The findings were compatible with compression of the neck by the branches of the tree, with the body weight of the decedent contributing to compression. Subsequent complete autopsy examination confirmed the cause of death as hanging. Following an inquest the death was ruled to be accidental.

  18. PREVENTION REFERENCE MANUAL: CONTROL TECHNOLOGIES, VOL. 2. POST-RELEASE MITIGATION MEASURES FOR CONTROLLING ACCIDENTAL RELEASES OF AIR TOXICS

    EPA Science Inventory

    The volume discusses prevention and protection measures for controlling accidental releases of air toxics. The probability of accidental releases depends on the extent to which deviations (in magnitude and duration) in the process can be tolerated before a loss of chemical contai...

  19. 19 CFR 158.27 - Accidental fire or other casualty.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Casualty, Loss, or Theft While in Customs Custody § 158.27 Accidental fire or other casualty. In the case... submitted: (a) A declaration of the master of the vessel, the conductor or driver of the vehicle, the... merchandise was on board the vessel or vehicle, in the warehouse, or otherwise in his charge, as the case may...

  20. The 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: summary of main findings and risk factors.

    PubMed

    Pandit, J J; Andrade, J; Bogod, D G; Hitchman, J M; Jonker, W R; Lucas, N; Mackay, J H; Nimmo, A F; O'Connor, K; O'Sullivan, E P; Paul, R G; Palmer, J H MacG; Plaat, F; Radcliffe, J J; Sury, M R J; Torevell, H E; Wang, M; Hainsworth, J; Cook, T M

    2014-10-01

    We present the main findings of the 5th National Audit Project on accidental awareness during general anaesthesia. Incidences were estimated using reports of accidental awareness as the numerator, and a parallel national anaesthetic activity survey to provide denominator data. The incidence of certain/probable and possible accidental awareness cases was ~1:19 600 anaesthetics (95% CI 1:16 700-23 450). However, there was considerable variation across subtypes of techniques or subspecialties. The incidence with neuromuscular blockade was ~1:8200 (1:7030-9700), and without it was ~1:135 900 (1:78 600-299 000). The cases of accidental awareness during general anaesthesia reported to 5th National Audit Project were overwhelmingly cases of unintended awareness during neuromuscular blockade. The incidence of accidental awareness during caesarean section was ~1:670 (1:380-1300). Two thirds (82, 66%) of cases of accidental awareness experiences arose in the dynamic phases of anaesthesia, namely induction of and emergence from anaesthesia. During induction of anaesthesia, contributory factors included: use of thiopental; rapid sequence induction; obesity; difficult airway management; neuromuscular blockade; and interruptions of anaesthetic delivery during movement from anaesthetic room to theatre. During emergence from anaesthesia, residual paralysis was perceived by patients as accidental awareness, and commonly related to a failure to ensure full return of motor capacity. One third (43, 33%) of accidental awareness events arose during the maintenance phase of anaesthesia, most due to problems at induction or towards the end of anaesthesia. Factors increasing the risk of accidental awareness included: female sex; age (younger adults, but not children); obesity; anaesthetist seniority (junior trainees); previous awareness; out-of-hours operating; emergencies; type of surgery (obstetric, cardiac, thoracic); and use of neuromuscular blockade. The following factors were

  1. Comparison of irradiation behaviour of HTR graphite grades

    NASA Astrophysics Data System (ADS)

    Heijna, M. C. R.; de Groot, S.; Vreeling, J. A.

    2017-08-01

    The INNOGRAPH irradiations were executed in the High Flux Reactor (HFR) in Petten by NRG supported by the European Framework programs HTR-M, RAPHAEL, and ARCHER to generate data on the irradiation behaviour of graphite grades for High Temperature Reactor (HTR) application available at that time. Samples of the graphite grades NBG-10, NBG-17, NBG-18, NBG-20, NBG-25, PCEA, PPEA, PCIB, and IG-110 have been irradiated at 750 °C and 950 °C. The inherent scatter induced by the probabilistic material behaviour of graphite requires uncertainty and scatter induced by test conditions and post-irradiation examination to be minimized. The INNOGRAPH irradiations supplied an adequate number of irradiated samples to enable accurate determination of material properties and their evolution under irradiation. This allows comparison of different graphite grades and a qualitative assessment of their appropriateness for HTR applications, as a basis of selection, design and core component lifetime. The results indicate that coarse grained graphite grades exhibit more favourable behaviour for application in HTRs due to their low dimensional anisotropy and fracture propagation resilience.

  2. Suicide and accidental death in Australia's rural farming communities: a review of the literature.

    PubMed

    Kennedy, Alison J; Maple, Myfanwy J; McKay, Kathy; Brumby, Susan A

    2014-01-01

    Australia's farmers constitute a heterogeneous group within the rural population. This literature review incorporates four broad areas: an understanding of farming communities, families and individuals and the contexts in which they live and work; an exploration of the challenges to morbidity and mortality that these communities face; a description of the patterns of suicide and accidental death in farming communities; and an outline of what is missing from the current body of research. Recommendations will be made on how these gaps may be addressed. In developing this comprehensive literature review, a snowballing and saturation approach was adopted. Initial search terms included suicid*, farm*, accident*, fatal*, death, sudden death, rural OR remote, Australia and NOT Australia. Databases searched included SCOPUS, PubMed, Proquest and SafetyLit; research from 1995 onwards was examined for relevance. Earlier seminal texts were also included. Reference lists of retrieved articles were searched and citations explored for further relevant research material. The primary focus was on Australian peer-reviewed research with supplementary grey literature. International material was used as examples. The literature variously describes farmers as members of both rural farming communities and farming families, and as individuals within an occupational classification. Within each of these classifications, there is evidence of the cumulative impact of a multiplicity of social, geographical and psychological factors relating to work, living and social arrangements that impact the health and wellbeing of Australia's farmers and their families, particularly accidental death and suicide. Research consistently demonstrates traumatic death to be at a greater rate than in the general Australian population, with reductions found more recently in some modes of farming-related accidental death. Patterns of accidental death and suicide are commonly linked to the changing shape of

  3. 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: summary of main findings and risk factors.

    PubMed

    Pandit, J J; Andrade, J; Bogod, D G; Hitchman, J M; Jonker, W R; Lucas, N; Mackay, J H; Nimmo, A F; O'Connor, K; O'Sullivan, E P; Paul, R G; Palmer, J H M G; Plaat, F; Radcliffe, J J; Sury, M R J; Torevell, H E; Wang, M; Hainsworth, J; Cook, T M

    2014-10-01

    We present the main findings of the 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia (AAGA). Incidences were estimated using reports of accidental awareness as the numerator, and a parallel national anaesthetic activity survey to provide denominator data. The incidence of certain/probable and possible accidental awareness cases was ~1:19,600 anaesthetics (95% confidence interval 1:16,700-23,450). However, there was considerable variation across subtypes of techniques or subspecialities. The incidence with neuromuscular block (NMB) was ~1:8200 (1:7030-9700), and without, it was ~1:135,900 (1:78,600-299,000). The cases of AAGA reported to NAP5 were overwhelmingly cases of unintended awareness during NMB. The incidence of accidental awareness during Caesarean section was ~1:670 (1:380-1300). Two-thirds (82, 66%) of cases of accidental awareness experiences arose in the dynamic phases of anaesthesia, namely induction of and emergence from anaesthesia. During induction of anaesthesia, contributory factors included: use of thiopental, rapid sequence induction, obesity, difficult airway management, NMB, and interruptions of anaesthetic delivery during movement from anaesthetic room to theatre. During emergence from anaesthesia, residual paralysis was perceived by patients as accidental awareness, and commonly related to a failure to ensure full return of motor capacity. One-third (43, 33%) of accidental awareness events arose during the maintenance phase of anaesthesia, mostly due to problems at induction or towards the end of anaesthesia. Factors increasing the risk of accidental awareness included: female sex, age (younger adults, but not children), obesity, anaesthetist seniority (junior trainees), previous awareness, out-of-hours operating, emergencies, type of surgery (obstetric, cardiac, thoracic), and use of NMB. The following factors were not risk factors for accidental awareness: ASA physical status, race, and use or omission

  4. The effects of pre-emptive low-dose X-ray irradiation on MIA induced inflammatory pain in rats

    NASA Astrophysics Data System (ADS)

    Hahm, Suk-Chan; Lee, Go-Eun; Kim, Eun-Hye; Kim, Junesun; Lee, Taewoong; Lee, Wonho

    2013-07-01

    This study was performed to determine the effect of pre-emptive low-dose irradiation on the development of inflammatory pain and to characterize the potential mechanisms underlying this effect in osteoarthritis (OA) animal model. Whole-body X-irradiations with 0.1, 0.5, 1 Gy or sham irradiations were performed for 3 days before the induction of ostearthritis with monosodium iodoacetate (MIA) (40 µl, in saline) into the right knee joint in male Sprague Dawley rats. Behavioral tests for arthritic pain including evoked and non-evoked pain were conducted before and after MIA injection and inducible nitric-oxide synthase (iNOS) expression level was measured by western blot. Low-dose radiation significantly prevented the development of mechanical allodynia and thermal hyperalgesia and reduction in weight bearing that is regarded as a behavioral signs of non-evoked pain following MIA injection. Low-dose radiation significantly inhibited the increase in iNOS expression after MIA injection in spinal L3-5 segments in rat. These data suggest that low-dose X-irradiation is able to prevent the development of arthritic pain through modulation of iNOS expression in the spinal cord dorsal horn. Thus, low-dose radiotherapy could be substituted in part for treatment with drugs for patients with chronic inflammatory disease in clinical setting.

  5. HZE ⁵⁶Fe-ion irradiation induces endothelial dysfunction in rat aorta: role of xanthine oxidase.

    PubMed

    Soucy, Kevin G; Lim, Hyun Kyo; Kim, Jae Hyung; Oh, Young; Attarzadeh, David O; Sevinc, Baris; Kuo, Maggie M; Shoukas, Artin A; Vazquez, Marcelo E; Berkowitz, Dan E

    2011-10-01

    Ionizing radiation has been implicated in the development of significant cardiovascular complications. Since radiation exposure is associated with space exploration, astronauts are potentially at increased risk of accelerated cardiovascular disease. This study investigated the effect of high atomic number, high-energy (HZE) iron-ion radiation on vascular and endothelial function as a model of space radiation. Rats were exposed to a single whole-body dose of iron-ion radiation at doses of 0, 0.5 or 1 Gy. In vivo aortic stiffness and ex vivo aortic tension responses were measured 6 and 8 months after exposure as indicators of chronic vascular injury. Rats exposed to 1 Gy iron ions demonstrated significantly increased aortic stiffness, as measured by pulse wave velocity. Aortic rings from irradiated rats exhibited impaired endothelial-dependent relaxation consistent with endothelial dysfunction. Acute xanthine oxidase (XO) inhibition or reactive oxygen species (ROS) scavenging restored endothelial-dependent responses to normal. In addition, XO activity was significantly elevated in rat aorta 4 months after whole-body irradiation. Furthermore, XO inhibition, initiated immediately after radiation exposure and continued until euthanasia, completely inhibited radiation-dependent XO activation. ROS production was elevated after 1 Gy irradiation while production of nitric oxide (NO) was significantly impaired. XO inhibition restored NO and ROS production. Finally, dietary XO inhibition preserved normal endothelial function and vascular stiffness after radiation exposure. These results demonstrate that radiation induced XO-dependent ROS production and nitroso-redox imbalance, leading to chronic vascular dysfunction. As a result, XO is a potential target for radioprotection. Enhancing the understanding of vascular radiation injury could lead to the development of effective methods to ameliorate radiation-induced vascular damage.

  6. Proton Irradiation Induced Effects in Titanium Carbide and Titanium Nitride: An Evaluation of Microstructures and Mechanical Properties

    NASA Astrophysics Data System (ADS)

    Dickerson, Clayton A.

    The materials TiC and TiN have been identified as potential candidate materials for advanced coated nuclear fuel components for the gas-cooled fast reactor (GFR). While a number of their thermal and mechanical properties have been studied, little is known about how these ceramics respond to particle irradiation. The goal of this study was to investigate the radiation effects in TiC and TiN by analyzing the irradiated microstructures and mechanical properties. Irradiations of TiC and TiN were conducted with 2.6 MeV protons at the University of Wisconsin -- Madison to simulate proposed conditions expected in a reactor. Each material was subjected to three incident proton fluences resulting in doses of ˜0.2 dpa to ˜1 dpa at three temperatures, 600°C, 800°C, and 900°C. Post irradiation examination included microstructural analysis via TEM, lattice parameter determinations with XRD, and mechanical property measurements with micro indentation hardness and fracture toughness tests. The predominant irradiation induced aggregate defects found by high resolution TEM and diffraction contrast TEM in both irradiated TiC and TiN were interstitial faulted dislocation loops. Only circular loops were identified in TiC while both circular and triangular loops were present in TiN. The influences on the microstructural evolution from a high inherent density of dislocations and high porosity were also determined. The strains resulting from the development of the defective microstructures were measured with XRD and shown to be highly dependent on the density of dislocation loops. Maximum strains for the irradiated samples were on the order of 0.5%. Measurements of the fracture toughness of Tic samples were made by ion milling the surface of the samples to create micro cantilever beams which were subsequently fractured by nano indentation. The formation of high densities of dislocation loops in the irradiated samples was found to significantly decrease the material's fracture

  7. Accidental falls in hospitalized children: an analysis of the vulnerabilities linked to the presence of caregivers.

    PubMed

    Bagnasco, A; Sobrero, M; Sperlinga, L; Tibaldi, L; Sasso, L

    2010-06-01

    This study stemmed from the data gathered by a research conducted by the coordinator of the Department of Healthcare Services and a group of nurses involved in a research on accidental falls in hospitalized children at the "G. Gaslini" Children's Hospital and Scientific Research Institute in Genoa, Italy. The first retrospective study evaluated the accidental falls in hospitalized children referred to the three-year period 2003-2006, while the second perspective study, referred to the trimester March-May 2007, found that the main cause of falls in children was parent's distraction. The method adopted in the first phase of our study was a proactive risk analysis (The Basics of Healthcare Failure Mode and Effect Analysis), identified in the first place by the VA National Centre for Patient Safety and applied to the "Child and parent hospital admission process". This proactive risk analysis has proven to be very effective in preventing the risk of accidental falls in hospitalized children through effective communication and educational interventions. The second phase of our study consisted of two Focus Groups for accidental traumatic events. The analysis of the results of the study showed how effective communication is instrumental, not only to have a better awareness of the children and their parents during their stay in hospital, but also to implement educational sessions on prevention to reduce the risk of accidental traumatic events. The present study contributes to improve safety and the quality of care by motivating nurses to keep their attention high on falls in hospitalized children, by monitoring and the development of new risk assessment tools.

  8. Accidental fatal lung injury by compressed air: a case report.

    PubMed

    Rayamane, Anand Parashuram; Pradeepkumar, M V

    2015-03-01

    Compressed air is being used extensively as a source of energy at industries and in daily life. A variety of fatal injuries are caused by improper and ignorant use of compressed air equipments. Many types of injuries due to compressed air are reported in the literature such as colorectal injury, orbital injury, surgical emphysema, and so on. Most of these injuries are accidental in nature. It is documented that 40 pounds per square inch pressure causes fatal injuries to the ear, eyes, lungs, stomach, and intestine. Openings of body are vulnerable to injuries by compressed air. Death due to compressed air injuries is rarely reported. Many cases are treated successfully by conservative or surgical management. Extensive survey of literature revealed no reports of fatal injury to the upper respiratory tract and lungs caused by compressed air. Here, we are reporting a fatal event of accidental death after insertion of compressed air pipe into the mouth. The postmortem findings are corroborated with the history and discussed in detail.

  9. Accidental degeneracy in photonic bands and topological phase transitions in two-dimensional core-shell dielectric photonic crystals.

    PubMed

    Xu, Lin; Wang, Hai-Xiao; Xu, Ya-Dong; Chen, Huan-Yang; Jiang, Jian-Hua

    2016-08-08

    A simple core-shell two-dimensional photonic crystal is studied where the triangular lattice symmetry and the C6 point group symmetry give rich physics in accidental touching points of photonic bands. We systematically evaluate different types of accidental nodal points at the Brillouin zone center for transverse-magnetic harmonic modes when the geometry and permittivity of the core-shell material are continuously tuned. The accidental nodal points can have different dispersions and topological properties (i.e., Berry phases). These accidental nodal points can be the critical states lying between a topological phase and a normal phase of the photonic crystal. They are thus very important for the study of topological photonic states. We show that, without breaking time-reversal symmetry, by tuning the geometry of the core-shell material, a phase transition into the photonic quantum spin Hall insulator can be achieved. Here the "spin" is defined as the orbital angular momentum of a photon. We study the topological phase transition as well as the properties of the edge and bulk states and their application potentials in optics.

  10. Accidental dural puncture, postdural puncture headache, intrathecal catheters, and epidural blood patch: revisiting the old nemesis.

    PubMed

    Kaddoum, Roland; Motlani, Faisal; Kaddoum, Romeo N; Srirajakalidindi, Arvi; Gupta, Deepak; Soskin, Vitaly

    2014-08-01

    One of the controversial management options for accidental dural puncture in pregnant patients is the conversion of labor epidural analgesia to continuous spinal analgesia by threading the epidural catheter intrathecally. No clear consensus exists on how to best prevent severe headache from occurring after accidental dural puncture. To investigate whether the intrathecal placement of an epidural catheter following accidental dural puncture impacts the incidence of postdural puncture headache (PDPH) and the subsequent need for an epidural blood patch in parturients. A retrospective chart review of accidental dural puncture was performed at Hutzel Women's Hospital in Detroit, MI, USA for the years 2002-2010. Documented cases of accidental dural punctures (N = 238) were distributed into two groups based on their management: an intrathecal catheter (ITC) group in which the epidural catheter was inserted intrathecally and a non-intrathecal catheter (non-ITC) group that received the epidural catheter inserted at different levels of lumbar interspaces. The incidence of PDPH as well as the necessity for epidural blood patch was analyzed using two-tailed Fisher's exact test. In the non-ITC group, 99 (54 %) parturients developed PDPH in comparison to 20 (37 %) in the ITC [odds ratio (OR), 1.98; 95 % confidence interval (CI), 1.06-3.69; P = 0.03]. Fifty-seven (31 %) of 182 patients in the non-ITC group required an epidural blood patch (EBP) (data for 2 patients of 184 were missing). In contrast, 7 (13 %) of parturients in the ITC group required an EBP. The incidence of EBP was calculated in parturients who actually developed headache to be 57 of 99 (57 %) in the non-ITC group versus 7 of 20 (35 %) in the ITC group (OR, 2.52; 95 % CI, 0.92-6.68; P = 0.07). The insertion of an intrathecal catheter following accidental dural puncture decreases the incidence of PDPH but not the need for epidural blood patch in parturients.

  11. Crystal plasticity modeling of irradiation growth in Zircaloy-2

    NASA Astrophysics Data System (ADS)

    Patra, Anirban; Tomé, Carlos N.; Golubov, Stanislav I.

    2017-08-01

    A physically based reaction-diffusion model is implemented in the visco-plastic self-consistent (VPSC) crystal plasticity framework to simulate irradiation growth in hcp Zr and its alloys. The reaction-diffusion model accounts for the defects produced by the cascade of displaced atoms, their diffusion to lattice sinks and the contribution to crystallographic strain at the level of single crystals. The VPSC framework accounts for intergranular interactions and irradiation creep, and calculates the strain in the polycrystalline ensemble. A novel scheme is proposed to model the simultaneous evolution of both, number density and radius, of irradiation-induced dislocation loops directly from experimental data of dislocation density evolution during irradiation. This framework is used to predict the irradiation growth behaviour of cold-worked Zircaloy-2 and trends compared to available experimental data. The role of internal stresses in inducing irradiation creep is discussed. Effects of grain size, texture and external stress on the coupled irradiation growth and creep behaviour are also studied and compared with available experimental data.

  12. Investigation of room temperature UV emission of ZnO films with different defect densities induced by laser irradiation.

    PubMed

    Zhao, Yan; Jiang, Yijian

    2010-08-01

    We studied the room temperature UV emission of ZnO films with different defect densities which is fabricated by KrF laser irradiation process. It is shown room temperature UV photoluminescence of ZnO film is composed of contribution from free-exciton (FX) recombination and its longitudinal-optical phonon replica (FX-LO) (1LO, 2LO). With increase of the defect density, the FX emission decreased and FX-LO emission increased dramatically; and the relative strengths of FX to FX-LO emission intensities determine the peak position and intensity of UV emission. What is more, laser irradiation with moderate energy density could induce the crystalline ZnO film with very flat and smooth surface. This investigation indicates that KrF laser irradiation could effectively modulate the exciton emission and surface morphology, which is important for the application of high performance of UV emitting optoelectronic devices. Copyright 2010 Elsevier B.V. All rights reserved.

  13. IL-15 signaling promotes adoptive effector T-cell survival and memory formation in irradiation-induced lymphopenia.

    PubMed

    Xu, Aizhang; Bhanumathy, Kalpana Kalyanasundaram; Wu, Jie; Ye, Zhenmin; Freywald, Andrew; Leary, Scot C; Li, Rongxiu; Xiang, Jim

    2016-01-01

    Lymphopenia promotes naïve T-cell homeostatic proliferation and adoptive effector T-cell survival and memory formation. IL-7 plays a critical role in homeostatic proliferation, survival and memory formation of naïve T-cells in lymphopenia, and its underlying molecular mechanism has also been well studied. However, the mechanism for adoptively transferred effector T-cell survival and memory formation is not fully understood. Here, we transferred in vitro-activated transgenic OT-I CD8(+) effector T-cells into irradiation (600 rads)-induced lymphopenic C57BL/6, IL-7 knockout (KO) and IL-15 KO mice, and investigated the survival and memory formation of transferred T-cells in lymphopenia. We demonstrate that transferred T-cells prolong their survival and enhance their memory in lymphopenic mice, in a manner that depends on IL-15 signaling, but not IL-7. We determine that in vitro stimulation of naïve or effector T-cells with IL-7 and IL-15 reduces IL-7Rα, and increases and/or maintains IL-15Rβ expression, respectively. Consistent with these findings, the expression of IL-7Rα and IL-15Rβ is down- and up-regulated, respectively, in vivo on transferred T-cells in an early phase post T-cell transfer in lymphopenia. We further show that in vitro IL-15 restimulation-induced memory T-cells (compared to IL-2 restimulation-induced effector T-cells) and in vivo transferred T-cells in irradiated IL-15-sufficient C57BL/6 mice (compared to IL-15-deficient IL-15 KO mice) have increased mitochondrial content, but less NADH and lower mitochondrial potential (ΔΨm), and demonstrate greater phosphorylation of signal transducers and activators of transcription-5 (STAT5) and Unc-51-like kinase-1 (ULK1), and higher expression of B-cell leukemia/lymphoma-2 (Bcl2) and memory-, autophagy- and mitochondrial biogenesis-related molecules. Irradiation-induced lymphopenia promotes effector T-cell survival via IL-15 signaling the STAT5/Bcl2 pathway, enhances T-cell memory formation via IL

  14. Detecting self-ion irradiation-induced void swelling in pure copper using transient grating spectroscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dennett, C. A.; So, K. P.; Kushima, A.

    Irradiation-induced void swelling remains a major challenge to nuclear reactor operation. Swelling may take years to initiate and often results in rapid material property degradation once started. Alloy development for advanced nuclear systems will require rapid characterization of the swelling breakaway dose in new alloys, yet this capability does not yet exist. In this paper, we demonstrate that transient grating spectroscopy (TGS) can detect void swelling in single crystal copper via changes in surface acoustic wave (SAW) velocity. Scanning transmission electron microscopy (STEM) links the TGS-observed changes with void swelling-induced microstructural evolution. Finally, these results are considered in the contextmore » of previous work to suggest that in situ TGS will be able to rapidly determine when new bulk materials begin void swelling, shortening alloy development and testing times.« less

  15. Detecting self-ion irradiation-induced void swelling in pure copper using transient grating spectroscopy

    DOE PAGES

    Dennett, C. A.; So, K. P.; Kushima, A.; ...

    2017-12-20

    Irradiation-induced void swelling remains a major challenge to nuclear reactor operation. Swelling may take years to initiate and often results in rapid material property degradation once started. Alloy development for advanced nuclear systems will require rapid characterization of the swelling breakaway dose in new alloys, yet this capability does not yet exist. In this paper, we demonstrate that transient grating spectroscopy (TGS) can detect void swelling in single crystal copper via changes in surface acoustic wave (SAW) velocity. Scanning transmission electron microscopy (STEM) links the TGS-observed changes with void swelling-induced microstructural evolution. Finally, these results are considered in the contextmore » of previous work to suggest that in situ TGS will be able to rapidly determine when new bulk materials begin void swelling, shortening alloy development and testing times.« less

  16. Accumulation and dissipation of positive charges induced on a PMMA build-up cap of an ionisation chamber by (60)Co gamma-ray irradiation.

    PubMed

    Morishita, Y; Takata, N

    2013-07-01

    The signal current from an ionisation chamber with a PMMA build-up cap decreases with irradiation time due to electric fields produced by positive charges induced on the cap. In the present study, it was confirmed that the signal current decreases faster for irradiation using narrower (60)Co gamma-ray beams. This is because the number of secondary electrons that are emitted from surrounding materials and penetrate the build-up cap is smaller in a narrower gamma-ray beam, so that fewer positive charges are neutralised. The ionisation chamber was first subjected to continuous gamma-ray irradiation for 24 h, following which it was irradiated with shorter periodic gamma-ray bursts while measuring the current signal. This allowed the coefficients of positive charge accumulation and dissipation to be determined. It was found that the dissipation coefficient has a large constant value during gamma-ray irradiation and decreases asymptotically to a small value after irradiation is stopped. From the coefficients, the minimum signal current was calculated, which is the value when accumulation and dissipation balance each other under continuous irradiation. The time required for the signal current to recover following irradiation was also calculated.

  17. Comparison of structural changes in skin and amnion tissue grafts for transplantation induced by gamma and electron beam irradiation for sterilization.

    PubMed

    Mrázová, H; Koller, J; Kubišová, K; Fujeríková, G; Klincová, E; Babál, P

    2016-06-01

    Sterilization is an important step in the preparation of biological material for transplantation. The aim of the study is to compare morphological changes in three types of biological tissues induced by different doses of gamma and electron beam radiation. Frozen biological tissues (porcine skin xenografts, human skin allografts and human amnion) were irradiated with different doses of gamma rays (12.5, 25, 35, 50 kGy) and electron beam (15, 25, 50 kGy). Not irradiated specimens served as controls. The tissue samples were then thawn and fixed in 10 % formalin, processed by routine paraffin technique and stained with hematoxylin and eosin, alcian blue at pH 2.5, orcein, periodic acid Schiff reaction, phosphotungstic acid hematoxylin, Sirius red and silver impregnation. The staining with hematoxylin and eosin showed vacuolar cytoplasmic changes of epidermal cells mainly in the samples of xenografts irradiated by the lowest doses of gamma and electron beam radiation. The staining with orcein revealed damage of fine elastic fibers in the xenograft dermis at the dose of 25 kGy of both radiation types. Disintegration of epithelial basement membrane, especially in the xenografts, was induced by the dose of 15 kGy of electron beam radiation. The silver impregnation disclosed nuclear chromatin condensation mainly in human amnion at the lowest doses of both radiation types and disintegration of the fine collagen fibers in the papillary dermis induced by the lowest dose of electron beam and by the higher doses of gamma radiation. Irradiation by both, gamma rays and the electron beam, causes similar changes on cells and extracellular matrix, with significant damage of the basement membrane and of the fine and elastic and collagen fibers in the papillary dermis, the last caused already by low dose electron beam radiation.

  18. Accidental Outcomes Guide Punishment in a “Trembling Hand” Game

    PubMed Central

    Cushman, Fiery; Dreber, Anna; Wang, Ying; Costa, Jay

    2009-01-01

    How do people respond to others' accidental behaviors? Reward and punishment for an accident might depend on the actor's intentions, or instead on the unintended outcomes she brings about. Yet, existing paradigms in experimental economics do not include the possibility of accidental monetary allocations. We explore the balance of outcomes and intentions in a two-player economic game where monetary allocations are made with a “trembling hand”: that is, intentions and outcomes are sometimes mismatched. Player 1 allocates $10 between herself and Player 2 by rolling one of three dice. One die has a high probability of a selfish outcome, another has a high probability of a fair outcome, and the third has a high probability of a generous outcome. Based on Player 1's choice of die, Player 2 can infer her intentions. However, any of the three die can yield any of the three possible outcomes. Player 2 is given the opportunity to respond to Player 1's allocation by adding to or subtracting from Player 1's payoff. We find that Player 2's responses are influenced substantially by the accidental outcome of Player 1's roll of the die. Comparison to control conditions suggests that in contexts where the allocation is at least partially under the control of Player 1, Player 2 will punish Player 1 accountable for unintentional negative outcomes. In addition, Player 2's responses are influenced by Player 1's intention. However, Player 2 tends to modulate his responses substantially more for selfish intentions than for generous intentions. This novel economic game provides new insight into the psychological mechanisms underlying social preferences for fairness and retribution. PMID:19707578

  19. Extrapyramidal symptoms following accidental ingestion of risperidone in a child.

    PubMed

    Cheslik, T A; Erramouspe, J

    1996-04-01

    To describe the development of extrapyramidal symptoms (EPS) precipitated by an accidental overdose of risperidone in a 3.5-year-old boy. The boy presented to the emergency department with bilateral upward eye gaze, jerky movements of his extremities, and motor restlessness following an accidental ingestion of a single 4-mg risperidone tablet. Decontamination with NaCl 0.9% lavage and activated charcoal with sorbitol was performed. His symptoms responded immediately to intravenous diphenhydramine (on 3 different occasions) during his first 9.5 hours of hospitalization. He experienced no additional EPS, and was discharged home approximately 33 hours following initial presentation. At home, he received three oral doses of diphenhydramine in the 24 hours following hospital discharge because of hand tremor, total body shivering, and eye wandering. These signs resolved without further complications. Although the incidence of EPS associated with therapeutic risperidone use is low, its occurrence following overdose is less clearly defined. This represents the first published case, to our knowledge, of risperidone overdose in a child and highlights the potential for dystonic reactions at low doses in this population. Seven intentional overdoses of risperidone in adults (aged 21-68 y) have been reported in the literature and are reviewed. Amounts ingested ranged from 5 to 270 mg. All adult patients appeared to have a relatively benign course. Reported symptoms included drowsiness, slurred speech, altered levels of consciousness, hypertension, tachycardia, electrocardiogram abnormalities, atypical motor behavior, tremors, and other EPS (not specified). Accidental ingestion of low doses of risperidone can cause EPS in children that may respond well to an anticholinergic agent. Overdose management includes gastrointestinal lavage, activated charcoal with cathartic, cardiovascular monitoring, and supportive therapy.

  20. Nanoscale Morphology Evolution Under Ion Irradiation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aziz, Michael J.

    We showed that the half-century-old paradigm of morphological instability under irradiation due to the curvature-dependence of the sputter yield, can account neither for the phase diagram nor the amplification or decay rates that we measure in the simplest possible experimental system -- an elemental semiconductor with an amorphous surface under noble-gas ion irradiation; We showed that a model of pattern formation based on the impact-induced redistribution of atoms that do not get sputtered away explains our experimental observations; We developed a first-principles, parameter-free approach for predicting morphology evolution, starting with molecular dynamics simulations of single ion impacts, lasting picoseconds, andmore » upscaling through a rigorous crater-function formalism to develop a partial differential equation that predicts morphology evolution on time scales more than twelve orders of magnitude longer than can be covered by the molecular dynamics; We performed the first quantitative comparison of the contributions to morphological instability from sputter removal and from impact-induced redistribution of atoms that are removed, and showed that the former is negligible compared to the latter; We established a new paradigm for impact-induced morphology evolution based on crater functions that incorporate both redistribution and sputter effects; and We developed a model of nanopore closure by irradiation-induced stress and irradiationenhanced fluidity, for the near-surface irradiation regime in which nuclear stopping predominates, and showed that it explains many aspects of pore closure kinetics that we measure experimentally.« less

  1. The AT{sub 1} Receptor Antagonist, L-158,809, Prevents or Ameliorates Fractionated Whole-Brain Irradiation-Induced Cognitive Impairment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Robbins, Mike E.; Brain Tumor Center of Excellence, Wake Forest University School of Medicine, Winston-Salem, NC; Payne, Valerie B.S.

    2009-02-01

    Purpose: We hypothesized that administration of the angiotensin type 1 (AT1) receptor antagonist, L-158,809, to young adult male rats would prevent or ameliorate fractionated whole-brain irradiation (WBI)-induced cognitive impairment. Materials and Methods: Groups of 80 young adult male Fischer 344 x Brown Norway (F344xBN) rats, 12-14 weeks old, received either: (1) fractionated WBI; 40 Gy of {gamma} rays in 4 weeks, 2 fractions/week, (2) sham-irradiation; (3) WBI plus L-158,809 (20 mg/L drinking water) starting 3 days prior, during, and for 14, 28, or 54 weeks postirradiation; and (4) sham-irradiation plus L-158,809 for 14, 28, or 54 weeks postirradiation. An additionalmore » group of rats (n = 20) received L-158,809 before, during, and for 5 weeks postirradiation, after which they received normal drinking water up to 28 weeks postirradiation. Results: Administration of L-158,809 before, during, and for 28 or 54 weeks after fractionated WBI prevented or ameliorated the radiation-induced cognitive impairment observed 26 and 52 weeks postirradiation. Moreover, giving L-158,809 before, during, and for only 5 weeks postirradiation ameliorated the significant cognitive impairment observed 26 weeks postirradiation. These radiation-induced cognitive impairments occurred without any changes in brain metabolites or gross histologic changes assessed at 28 and 54 weeks postirradiation, respectively. Conclusions: Administering L-158,809 before, during, and after fractionated WBI can prevent or ameliorate the chronic, progressive, cognitive impairment observed in rats at 26 and 52 weeks postirradiation. These findings offer the promise of improving the quality of life for brain tumor patients.« less

  2. A case of an accidental exposure to a veterinary insecticide product formulation.

    PubMed

    Sidhu, K S; Collisi, M B

    1989-02-01

    A veterinary technician while opening a package was accidentally exposed to a commercial canned product formulation containing insecticides and solvents. The patient was twice briefly treated and released as an outpatient from 2 different hospitals on the first and second day after the exposure. However, on the fourth day, as some of the symptoms (headache, nausea, vomiting, diarrhea, difficult breathing) persisted, the patient was admitted to another hospital. The patient was treated for exposure to organophosphates and solvents and was released after 13 days. The patient developed diabetes insipidus, a condition which lasted for approximately 1 year. The cause of the temporary development of diabetes insipidus is not understood. There is a need to prevent and minimize such accidental exposures in future.

  3. Sodium orthovanadate (vanadate), a potent mitigator of radiation-induced damage to the hematopoietic system in mice

    PubMed Central

    Wang, Bing; Tanaka, Kaoru; Morita, Akinori; Ninomiya, Yasuharu; Maruyama, Kouichi; Fujita, Kazuko; Hosoi, Yoshio; Nenoi, Mitsuru

    2013-01-01

    Previous in vitro and in vivo studies have shown that sodium orthovanadate (vanadate), an inorganic vanadium compound, could effectively suppress radiation-induced p53-mediated apoptosis via both transcription-dependent and transcription-independent pathways. As a potent radiation protector administered at a dose of 20 mg/kg body weight (20 mg/kg) prior to total body irradiation (TBI) by intra-peritoneal (ip) injection, it completely protected mice from hematopoietic syndrome and partially from gastrointestinal syndrome. In the present study, radiation mitigation effects from vanadate were investigated by ip injection of vanadate after TBI in mice. Results showed that a single administration of vanadate at a dose of 20 mg/kg markedly improved the 30-day survival rate and the peripheral blood hemogram, relieved bone marrow aplasia and decreased occurrence of the bone marrow micronucleated erythrocytes in the surviving animals. The dose reduction factor was 1.2 when a single dose of 20 mg/kg was administered 15 min after TBI in mice using the 30-day survival test as the endpoint. Results also showed that either doubling the vanadate dose (40 mg/kg) in a single administration or continuing the vanadate treatment (after a single administration at 20 mg/kg) from the following day at a dose of 5 mg/kg per day for 4 consecutive days further significantly improved the efficacy for rescuing bone marrow failure in the 30-day survival test. Taken together, these findings indicate that vanadate would be a potent mitigator suppressing the acute lethality (hematopoietic syndrome) and minimizing the detrimental effects (anhematopoiesis and delayed genotoxic effects) induced by TBI in mice. PMID:23349341

  4. Parental cannabis abuse and accidental intoxications in children: prevention by detecting neglectful situations and at-risk families.

    PubMed

    Pélissier, Fanny; Claudet, Isabelle; Pélissier-Alicot, Anne-Laure; Franchitto, Nicolas

    2014-12-01

    Cannabis intoxication in toddlers is rare and mostly accidental. Our objectives were to focus on the characteristics and management of children under the age of 6 years who were admitted to our emergency department with cannabis poisoning reported as accidental by parents, and to point out the need to consider accidental cannabis ingestions as an indicator of neglect. The medical records of children hospitalized for cannabis poisoning in a pediatric emergency department from January 2007 to November 2012 were retrospectively evaluated. Data collected included age, sex, drug ingested, source of drug, intentional versus accidental ingestion, pediatric intensive care unit or hospital admission, treatment and length of hospital stay, toxicology results, and rate of child protectives services referral. Twelve toddlers (4 boys and 8 girls; mean age, 16.6 months) were included. All had ingested cannabis. Their parents reported the ingestion. Seven children experienced drowsiness or hypotonia. Three children were given activated charcoal. Blood screening for cannabinoids, performed in 2 cases, was negative in both, and urine samples were positive in 7 children (70%). All children had favorable outcomes after being hospitalized from 2 to 48 hours. Nine children were referred to social services for further assessment before discharge. Cannabis intoxication in children should be reported to child protection services with the aim of prevention, to detect situations of neglect and at-risk families. Legal action against the parents may be considered. Accidental intoxication and caring parents should be no exception to this rule.

  5. Oligodendrocyte progenitor cell (OPC) transplantation is unlikely to offer a means of preventing X-irradiation induced damage in the CNS.

    PubMed

    Chari, Divya M; Gilson, Jennifer M; Franklin, Robin J M; Blakemore, William F

    2006-03-01

    Oligodendrocyte lineage cells [oligodendrocytes and their parent cells, the oligodendrocyte progenitor cells (OPCs)] are depleted by X-irradiation and progenitor cell transplantation has been proposed as a therapeutic strategy to counteract radiation induced myelopathy. Previous studies have demonstrated that oligodendrocyte progenitor cell (OPC) depletion is a prerequisite for establishing transplanted OPCs in normal tissue. One can therefore predict that the extent and timing of OPC depletion and regeneration following X-irradiation will be crucial factors in determining the feasibility of this therapeutic approach. To address this issue, we have examined the time course of OPC depletion and regeneration following a range of X-irradiation doses (5 to 40 Gy), and its relationship to establishing transplanted OPCs in X-irradiated tissue. Doses above 10 Gy resulted in rapid death of OPCs. With doses up to 20 Gy, surviving X-irradiated OPCs were capable of robust regeneration, restoring normal densities within 6 weeks. Transplanted OPCs could only be established in tissue that had been exposed to > or =20 Gy. Since 20 Gy is close to the ED50 for radiation necrosis, our findings demonstrate the limitation of OPC replacement strategies.

  6. Correlation of Hsp110 expression with caspase-3 and -9 during apoptosis induced by in vivo embryonic exposition to retinoic acid or irradiation in early mouse craniofacial development.

    PubMed

    Gashegu, J; Vanmuylder, N; Philippson, C; Choa-Duterre, M; Rooze, M; Louryan, S

    2006-05-01

    To analyze the expression and role of three proteins (HSP110, caspase-3 and caspase-9) during craniofacial development. Seven pregnant C57Bl/6J mice received, by force-feeding at gestation day 9 (E9), 80 mg/kg of all-trans retinoic acid mixed to sesame oil. Seven pregnant NMRI mice received two grays irradiation at the same gestation day. Control mice of both strains (seven mice for each strain) were not submitted to any treatment. Embryos were obtained at various stages after exposition (3, 6, 12 and 24 h), fixed, dehydrated and embedded. Coronal sections (5 microm) were made. Slide staining occurred alternatively using anti-Hsp110, anti-caspase-3 and anti-caspase-9 immunohistochemistry. Expression of HSP110, caspase-3 and caspase-9 was found in cells of well-known locations of programmed cell death. After retinoic acid exposure, expressions were increased especially in neural crest cells of mandibular and hyoid arches. Quantification of positive cells shows that caspase-9 and Hsp110 were expressed before caspase-3. After irradiation, the expression of the three proteins quickly increased with a maximum 3 h after irradiation. For all three models of apoptosis (physiological, retinoic-induced and irradiation-induced) HSP110 positive cells were more numerous than caspase-3 positive cells. Caspase-3 positive cells were more numerous than caspase-9 positive cells especially in mesectodermal irradiation-induced apoptotic cells. The findings show a potential function of HSP110 in apoptosis during embryo development. Caspase-3-expressing cells are more numerous than cells expressing caspase-9, especially irradiation-induced apoptotic neural crest cells. This suggests that other caspases, still to be identified, may activate caspase-3 in this model.

  7. Intra-oral administration of rebamipide liquid prevents tongue injuries induced by X-ray irradiation in rats.

    PubMed

    Nakashima, Takako; Uematsu, Naoya; Sakurai, Kazushi

    2017-07-01

    Oral mucositis is a common and serious side effect in patients who undergo cytotoxic cancer therapies. The purpose of this study was to investigate the preventive effects of rebamipide on radiation-induced glossitis model in rats. Glossitis was induced by a single dose of 15 Gy of X-rays to the snouts of rats (day 0). A novel form of rebamipide liquid comprising its submicronized crystals was administered intra-orally. The preventive effect of rebamipide on tongue injuries was macroscopically evaluated on day 7 following irradiation. The pretreatment period, dosing frequency, and dose dependency of rebamipide were examined. Two percent rebamipide liquid, administered six times a day for 14 days from day -7 to day 6, significantly decreased the ulcer-like area. However, no significant effect was observed when rebamipide was given either from day -4 or from day -1. Four or six times daily, 2% rebamipide liquid significantly inhibited the ulcer-like injury area ratio, but not when given twice daily. Rebamipide liquid, 1, 2, and 4% six times daily significantly reduced the area ratios of total injury and ulcer-like injury in a dose-dependent manner. Gene expression and protein levels of proinflammatory cytokines and chemokines were dramatically elevated in the irradiated tongues of control rats on day 7 without rebamipide liquid treatment. They were dose-dependently and significantly suppressed in rebamipide-treated groups. Intra-oral administration of rebamipide liquid prevented oral mucositis dose-dependently accompanied by the suppression of inflammatory expression in the radiation-induced rats' glossitis model.

  8. Food Irradiation Using Electron Beams and X-Rays

    NASA Astrophysics Data System (ADS)

    Miller, Bruce

    2003-04-01

    In this presentation we will discuss the technology of food irradiation using electron accelerators. Food irradiation has generally come to describe the use of ionizing radiation to decrease the population of, or prevent the growth of, undesirable biological organisms in food. The many beneficial applications include insect disinfestation, sprouting inhibition, delayed ripening, and the enhanced safety and sterilization of fresh and frozen meat products, seafood, and eggs. With special regard to food safety, bacteria such as Salmonella enteridis, Listeria monocytogenes, Campylobacter jejuni and Escherichia coli serotype O157:H7 are the primary causes of food poisoning in industrialized countries. Ionizing doses in the range of only 1-5 kilogray (kGy) can virtually eliminate these organisms from food, without affecting the food's sensory and nutritional qualities, and without inducing radioactivity. The key elements of an accelerator-based irradiation facility include the accelerator system, a scanning system, and a material handling system that moves the product through the beam in a precisely controlled manner. Extensive radiation shielding is necessary to reduce the external dose to acceptable levels, and a safety system is necessary to prevent accidental exposure of personnel during accelerator operation. Parameters that affect the dose distribution must be continuously monitored and controlled with process control software. The choice of electron beam vs x-ray depends on the areal density (density times thickness) of the product and the anticipated mass throughput. To eliminate nuclear activation concerns, the maximum kinetic energy of the accelerator is limited by regulation to 10 MeV for electron beams, and 5 MeV for x-rays. From penetration considerations, the largest areal density that can be treated by double-sided electron irradiation at 10 MeV is about 8.8 g/cm2. Products having greater areal densities must be processed using more penetrating x-rays. The

  9. Effects of a turmeric extract (Curcuma longa) on chronic ultraviolet B irradiation-induced skin damage in melanin-possessing hairless mice.

    PubMed

    Sumiyoshi, Maho; Kimura, Yoshiyuki

    2009-12-01

    Turmeric (the rhizomes of Curcuma longa L., Zingiberacease) is widely used as a dietary pigment and spice, and has been traditionally used for the treatment of inflammation, skin wounds and hepatic disorders in Ayurvedic, Unani and Chinese medicine. Although the topical application or oral administration of turmeric is used to improve skin trouble, there is no evidence to support this effect. The aim of this study was to clarify whether turmeric prevents chronic ultraviolet B (UVB)-irradiated skin damage. We examined the effects of a turmeric extract on skin damage including changes in skin thickness and elasticity, pigmentation and wrinkling caused by long-term, low-dose ultraviolet B irradiation in melanin-possessing hairless mice. The extract (at 300 or 1000 mg/kg, twice daily) prevented an increase in skin thickness and a reduction in skin elasticity induced by chronic UVB exposure. It also prevented the formation of wrinkles and melanin (at 1000 mg/kg, twice daily) as well as increases in the diameter and length of skin blood vessels and in the expression of matrix metalloproteinase-2 (MMP-2). Prevention of UVB-induced skin aging by turmeric may be due to the inhibition of increases in MMP-2 expression caused by chronic irradiation.

  10. Effect of irradiation temperature on microstructural changes in self-ion irradiated austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Jin, Hyung-Ha; Ko, Eunsol; Lim, Sangyeob; Kwon, Junhyun; Shin, Chansun

    2017-09-01

    We investigated the microstructural and hardness changes in austenitic stainless steel after Fe ion irradiation at 400, 300, and 200 °C using transmission electron microscopy (TEM) and nanoindentation. The size of the Frank loops increased and the density decreased with increasing irradiation temperature. Radiation-induced segregation (RIS) was detected across high-angle grain boundaries, and the degree of RIS increases with increasing irradiation temperature. Ni-Si clusters were observed using high-resolution TEM in the sample irradiated at 400 °C. The results of this work are compared with the literature data of self-ion and proton irradiation at comparable temperatures and damage levels on stainless steels with a similar material composition with this study. Despite the differences in dose rate, alloy composition and incident ion energy, the irradiation temperature dependence of RIS and the size and density of radiation defects followed the same trends, and were very comparable in magnitude.

  11. Hazard assessment of substances produced from the accidental heating of chemical compounds.

    PubMed

    Lunghi, A; Gigante, L; Cardillo, P; Stefanoni, V; Pulga, G; Rota, R

    2004-12-10

    Accidental events concerning process industries can affect not only the staff working in, but also the environment and people living next to the factory. For this reason a regulation is imposed by the European Community to prevent accidents that could represent a risk for the population and the environment. In particular, Directive 96/82/CE, the so-called 'Seveso II directive', requests a risk analysis involving also the hazardous materials generated in accidental events. Therefore, it is necessary to develop simple and economic procedure to foresee the hazardous materials that can be produced in the case of major accidents, among which the accidental heating of a chemical due to a fire or a runaway reaction is one of the most frequent. The procedure proposed in this work is based on evolved gas analysis methodology that consists in coupling two instruments: a thermogravimetric analyzer or a flash pyrolyzer, that are employed to simulate accident conditions, and a FTIR spectrometer that can be used to detect the evolved gas composition. More than 40 materials have been examined in various accident scenarios and the obtained data have been statistically analyzed in order to identify meaningful correlations between the presence of a chemical group in the molecule of a chemical and the presence of a given hazardous species in the fume produced.

  12. [Promotive effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on recovery from neutropenia induced by fractionated irradiation in mice].

    PubMed

    Kabaya, K; Watanabe, M; Kusaka, M; Seki, M; Fushiki, M

    1994-08-25

    The effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on the recovery from neutropenia induced by fractionated whole-body irradiation was investigated in mice. Male 7-week old C3H/HeN mice received a total of ten exposures of 0.25 Gy/day from day 1 to 5 and from day 8 to 12. Peripheral neutropenia with a nadir on day 17 was caused by the fractionated irradiation. Daily subcutaneous injections of rhG-CSF at 0.25 and 2.5 micrograms/body/day from day 1 to 21 promoted the recovery of neutrophils in a dose-dependent manner. The kinetics of morphologically identifiable bone marrow cells were studied to clarify the mechanism behind the promotive effect of this factor. A slight decrease in mitotic immature granulocytes, such as myeloblasts, promyelocytes and myelocytes on day 5, and a drastic decrease in metamyelocytes and marrow neutrophils on days 5, 9, and 17 were seen in the femur of irradiated mice. Treatment using rhG-CSF caused an increase in immature granulocytes of all differential stages in the femur. Microscopic findings of the femurs and spleens also revealed an increase in immature granulocytes in these organs in mice injected with rhG-CSF. These results indicate that rhG-CSF accelerates granulopoiesis in the femur and spleen, thereby promoting recovery from neutropenia induced by fractionated irradiation.

  13. Proton irradiation effects on beryllium - A macroscopic assessment

    NASA Astrophysics Data System (ADS)

    Simos, Nikolaos; Elbakhshwan, Mohamed; Zhong, Zhong; Camino, Fernando

    2016-10-01

    Beryllium, due to its excellent neutron multiplication and moderation properties, in conjunction with its good thermal properties, is under consideration for use as plasma facing material in fusion reactors and as a very effective neutron reflector in fission reactors. While it is characterized by unique combination of structural, chemical, atomic number, and neutron absorption cross section it suffers, however, from irradiation generated transmutation gases such as helium and tritium which exhibit low solubility leading to supersaturation of the Be matrix and tend to precipitate into bubbles that coalesce and induce swelling and embrittlement thus degrading the metal and limiting its lifetime. Utilization of beryllium as a pion production low-Z target in high power proton accelerators has been sought both for its low Z and good thermal properties in an effort to mitigate thermos-mechanical shock that is expected to be induced under the multi-MW power demand. To assess irradiation-induced changes in the thermal and mechanical properties of Beryllium, a study focusing on proton irradiation damage effects has been undertaken using 200 MeV protons from the Brookhaven National Laboratory Linac and followed by a multi-faceted post-irradiation analysis that included the thermal and volumetric stability of irradiated beryllium, the stress-strain behavior and its ductility loss as a function of proton fluence and the effects of proton irradiation on the microstructure using synchrotron X-ray diffraction. The mimicking of high temperature irradiation of Beryllium via high temperature annealing schemes has been conducted as part of the post-irradiation study. This paper focuses on the thermal stability and mechanical property changes of the proton irradiated beryllium and presents results of the macroscopic property changes of Beryllium deduced from thermal and mechanical tests.

  14. Irradiation creep due to SIPA under cascade damage conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Woo, C.H.; Garner, F.A.; Holt, R.A.

    1992-12-31

    This paper derives the relationships between void swelling and irradiation creep due to Stress-Induced Preferred Absorption (SIPA) and SIPA-Induced Growth (SIG) under cascade damage conditions in an irradiated pressurized tube. It is found that at low swelling rates irradiation creep is a major contribution to the total diametral strain rate of the tube, whereas at high swelling rates the creep becomes a minor contribution. The anisotropy of the corresponding dislocation structure is also predicted to decline as the swelling rate increases. The theoretical predictions are found to agree very well with experimental results.

  15. Laboratory simulation of irradiation-induced dielectric breakdown in spacecraft charging

    NASA Technical Reports Server (NTRS)

    Yadlowsky, E. J.; Churchill, R. J.; Hazelton, R. C.

    1980-01-01

    The discharging of dielectric samples irradiated by a beam of monoenergetic electrons is investigated. The development of a model, or models, which describe the discharge phenomena occuring on the irradiated dielectric targets is discussed. The electrical discharge characteristics of irradiated dielectric samples are discussed and the electrical discharge paths along dielectric surfaces and within the dielectric material are determined. The origin and destination of the surface emitted particles is examined and the charge and energy balance in the system is evaluated.

  16. Structural responses of metallic glasses under neutron irradiation.

    PubMed

    Yang, L; Li, H Y; Wang, P W; Wu, S Y; Guo, G Q; Liao, B; Guo, Q L; Fan, X Q; Huang, P; Lou, H B; Guo, F M; Zeng, Q S; Sun, T; Ren, Y; Chen, L Y

    2017-12-01

    Seeking nuclear materials that possess a high resistance to particle irradiation damage is a long-standing issue. Permanent defects, induced by irradiation, are primary structural changes, the accumulation of which will lead to structural damage and performance degradation in crystalline materials served in nuclear plants. In this work, structural responses of neutron irradiation in metallic glasses (MGs) have been investigated by making a series of experimental measurements, coupled with simulations in ZrCu amorphous alloys. It is found that, compared with crystalline alloys, MGs have some specific structural responses to neutron irradiation. Although neutron irradiation can induce transient vacancy-like defects in MGs, they are fully annihilated after structural relaxation by rearrangement of free volumes. In addition, the rearrangement of free volumes depends strongly on constituent elements. In particular, the change in free volumes occurs around the Zr atoms, rather than the Cu centers. This implies that there is a feasible strategy for identifying glassy materials with high structural stability against neutron irradiation by tailoring the microstructures, the systems, or the compositions in alloys. This work will shed light on the development of materials with high irradiation resistance.

  17. Radiation-induced cystitis following intracavitary irradiation for superficial bladder cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maatman, T.J.; Novick, A.C.; Montague, D.K.

    Intracavitary irradiation is effective in the treatment of noninvasive papillary transitional cell carcinoma and carcinoma in situ of the bladder. Mortality has not been associated with this form of therapy. The morbidity associated with intracavitary irradiation consists of mild to severe radiation cystitis and we report 2 such cases. One patient is from a series of 65 patients with noninvasive bladder tumors treated with intracavitary irradiation at this clinic since 1965. The second patient had noninvasive bladder tumors and was treated with intracavitary irradiation elsewhere. In both patients severe radiation cystitis subsequently developed, requiring simple cystectomy and urinary diversion. Themore » potential for this serious side effect must be considered when choosing a form of therapy for patients with noninvasive papillary transitional cell carcinoma and carcinoma in situ of the bladder.« less

  18. [Changes in cellular radiosensitivity after low dose irradiation].

    PubMed

    Pelevina, I I; Aleshchenko, A V; Antoshchina, M M; Kudriashova, O V; Riabchenko, N I; Akleev, A V

    2012-01-01

    When the adaptive response (AR) was studied on human blood lymphocytes, a new dependence was discovered. This dependence defines the direction of the radiosensitivity change after a low dose of irradiation. Using micronucleus (MN) test with cytochalasin B the dependence between the cell reaction after low level irradiation and radiosensititvity (the effect after irradiation at the dose of 1 Gy) was observed. The negative correlation between the frequency of AR manifestation, sensibilization, intermediate links and radiosensitivity was discovered. This regularity is observed in the population of Moscow, Obninsk, Chelyabinsk region (irradiated and control) inhabitants, Chernobyl accident liquidators, Moscow children, in individuals with Hodgkin's lymphoma before and during treatment. The negative correlation is also noted by AR determination with two irradiation schemes: in one or two different cell cycle phases (G1-G1 or G1-G2). Similar links are observed using the chromosome methaphase analysis (the frequency of cells with chromosome aberrations). So, the results of the experiments conducted allow us to suppose that the connection between the cell radiosensitivity and a different type of reaction after low dose irradiation--from AR to the increase in radiosensitivity (sensibilization) is a general regularity. AR is induced by low level irradiation and high cell radiosensitivity, while sensibilization is induced by low radiosensitivity. Since AR and sensibilization can be induced not only by irradiation, but many different chemicals and physical agents, the described correlation can be observed in the case of different exposures. Cellular AR and sensibilization are integral indexes depending on many genetic and epigenetic factors, as well as on the initiation of a large number of events. However, the discovered mechanisms of interrelations are still difficult to explain.

  19. Immunogenicity of the irradiated Schistosoma mansoni schistosomula vaccine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Othman, M.I.

    1986-01-01

    This work was initiated to investigate the immunogenicity of the irradiated schistosomula vaccine with respect to its: ability to protect against challenge infection; ability to induce antibody responses in Western blot (WB) assay; and the antibodies' ability to kill the parasites; ultrastructural changes of the vaccine organism's tegument; antibody binding to their surface in immunofluorescence (IFA) and immunoelectron microscopic (IEM) assays and surface antigen recognition with different sera in WB. Irradiated schistosomula, freshly prepared or cultured up to 48 hours, were able to induce significant levels of protection (27%-67%). however, irradiated cercariae offered greater protection (52%-72%). Vaccination of mice withmore » irradiated schistosomula, led to higher antibody responses to adult freeze-thaw (AFT) and schistosomula membrane extract (SME) antigens with respect to to time and number of recognized antigens.« less

  20. A study of irradiation-induced defects in silicon using low temperature photoluminescence

    NASA Technical Reports Server (NTRS)

    Streetman, B. G.

    1971-01-01

    Irradiation-induced defects in silicon, using low temperature photoluminescence as a probe of defect properties were investigated. The goal of this research was to gain new understanding of defects which degrade solar cell characteristics in a radiation environment. In this regard, an important aspect of this program was a study of radiation damage and annealing in lithium doped silicon, which is useful in reducing solar cell degradation. Luminescence was used to study defects because this property reveals electron transitions through a number of defect energy levels at any given annealing stage; the luminescence spectra give excellent resolution of many defect energy levels, and these measurements can be used to give defect symmetry in the lattice, impurity dependence, and annealing properties.

  1. Irradiation Creep in Graphite

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ubic, Rick; Butt, Darryl; Windes, William

    2014-03-13

    An understanding of the underlying mechanisms of irradiation creep in graphite material is required to correctly interpret experimental data, explain micromechanical modeling results, and predict whole-core behavior. This project will focus on experimental microscopic data to demonstrate the mechanism of irradiation creep. High-resolution transmission electron microscopy should be able to image both the dislocations in graphite and the irradiation-induced interstitial clusters that pin those dislocations. The team will first prepare and characterize nanoscale samples of virgin nuclear graphite in a transmission electron microscope. Additional samples will be irradiated to varying degrees at the Advanced Test Reactor (ATR) facility and similarlymore » characterized. Researchers will record microstructures and crystal defects and suggest a mechanism for irradiation creep based on the results. In addition, the purchase of a tensile holder for a transmission electron microscope will allow, for the first time, in situ observation of creep behavior on the microstructure and crystallographic defects.« less

  2. Radiation-induced effects in the electron-beam irradiation of dietary flavonoids

    NASA Astrophysics Data System (ADS)

    Tamba, M.; Torreggiani, A.

    2004-09-01

    The harmful effects of oxidative processes in living organisms can be reduced by the dietary intake of flavonoids, a class of phenolic compounds ubiquitous in plants and widely found in a number of fruits, vegetables and beverages. Many fruits and vegetables are treated by irradiation to solve preservation problems and a radical-induced degradation of nutrients, including polyphenols, may occur. The free radical chemistry of two abundant flavonoids in food, catechin and quercetin, have been investigated by using pulse radiolysis technique. The central role of the phenoxyl-type radical and the strong influence of the state of protonation of the compounds on the pathway of formation and decay of the corresponding oxidized radicals has been evidenced from the spectral properties and chemical reactivity of the radicals derived from the attack of several oxidizing species ( ṡOH, N 3ṡ SO 4-ṡ).

  3. Degradation of N-nitrosodimethylamine (NDMA) and its precursor dimethylamine (DMA) in mineral micropores induced by microwave irradiation.

    PubMed

    He, Yuanzhen; Cheng, Hefa

    2016-05-01

    Removal of N-nitrosodimethylamine (NDMA) in drinking water treatment poses a significant technical challenge due to its small molecular size, high polarity and water solubility, and poor biodegradability. Degradation of NDMA and its precursor, dimethylamine (DMA), was investigated by adsorbing them from aqueous solution using porous mineral sorbents, followed by destruction under microwave irradiation. Among the mineral sorbents evaluated, dealuminated ZSM-5 exhibited the highest sorption capacities for NDMA and DMA, which decreased with the density of surface cations present in the micropores. In contrast, the degradation rate of the sorbed NDMA increased with the density of surface cations under microwave irradiation. Evolutions of the degradation products and C/N ratio indicate that the sorbed NDMA and DMA could be eventually mineralized under continuous microwave irradiation. The degradation rate was strongly correlated with the bulk temperature of ZSM-5 and microwave power, which is consistent with the mechanism of pyrolysis caused by formation of micro-scale "hot spots" within the mineral micropores under microwave irradiation. Compared to existing treatment options for NDMA removal, microporous mineral sorption coupled with microwave-induced degradation has the unique advantages of being able to simultaneously remove NDMA and DMA and cause their full mineralization, and thus could serve as a promising alternative method. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Electron irradiation induced amorphous SiO2 formation at metal oxide/Si interface at room temperature; electron beam writing on interfaces.

    PubMed

    Gurbán, S; Petrik, P; Serényi, M; Sulyok, A; Menyhárd, M; Baradács, E; Parditka, B; Cserháti, C; Langer, G A; Erdélyi, Z

    2018-02-01

    Al 2 O 3 (5 nm)/Si (bulk) sample was subjected to irradiation of 5 keV electrons at room temperature, in a vacuum chamber (pressure 1 × 10 -9 mbar) and formation of amorphous SiO 2 around the interface was observed. The oxygen for the silicon dioxide growth was provided by the electron bombardment induced bond breaking in Al 2 O 3 and the subsequent production of neutral and/or charged oxygen. The amorphous SiO 2 rich layer has grown into the Al 2 O 3 layer showing that oxygen as well as silicon transport occurred during irradiation at room temperature. We propose that both transports are mediated by local electric field and charged and/or uncharged defects created by the electron irradiation. The direct modification of metal oxide/silicon interface by electron-beam irradiation is a promising method of accomplishing direct write electron-beam lithography at buried interfaces.

  5. New insight into mitochondrial changes in vascular endothelial cells irradiated by gamma ray.

    PubMed

    Hu, Shunying; Gao, Yajing; Zhou, Hao; Kong, Fanxuan; Xiao, Fengjun; Zhou, Pingkun; Chen, Yundai

    2017-05-01

    To investigate alterations of mitochondria in irradiated endothelial cells to further elucidate the mechanism underlying radiation-induced heart disease. Experiments were performed using human umbilical vein endothelial cells (HUVECs). HUVECs were irradiated with single gamma ray dose of 0, 5, 10 and 20 Gy, respectively. Apoptosis was assessed by flow cytometry at 24, 48 and 72 h post-irradiation, respectively. The intracellular reactive oxygen species (ROS) was measured with 2',7'-dichlorofluorescein-diacetate (DCFH-DA) at 24 h post-irradiation. Mitochondrial membrane potential (ΔΨm) by JC-1 and the opening of mitochondrial permeability transition pore (mPTP) by a calcein-cobalt quenching method were detected at 24 h post-irradiation in order to measure changes of mitochondria induced by gamma ray irradiation. Gamma ray irradiation increased HUVECs apoptosis in a dose-dependent and time-dependent manner. Irradiation also promoted ROS production in HUVECs in a dose-dependent manner. At 24 h post-irradiation, the results showed that irradiation decreases ΔΨm, however, paradoxically, flow cytometry showed green fluorescence instensity higher in irradiated HUVECs than in control HUVECs in an irradiation dose-dependent manner which indicated gamma ray irradiation inhibited mPTP opening in HUVECs. Gamma ray irradiation induces apoptosis and ROS production of endothelial cells, and decreases ΔΨm meanwhile contradictorily inhibiting the opening of mPTP.

  6. [The accidental detection of apical periodontitis].

    PubMed

    Wesselink, P R

    2011-04-01

    Accidental detection of an asymptomatic apical periodontitis raises the question whether this lesion should be treated or not. Arguments favouring treatment are that the inflammation may cause pain in the future, may enlarge or may negatively affect the host's resistance. Reasons for not treating may be that treatment weakens the tooth, may cause iatrogenic damage and that treatment is expensive and burdensome for the patient and does not lead in all cases to complete healing. Scientific evidence supporting either choice, whether treating the lesion or not, is lacking. In making such decisions, therefore, personal judgments by the patient and the dentist concerning the impact on the quality of life of the patient play an important role.

  7. Risk of pure red cell aplasia in patients with hepatitis C receiving antiviral therapy and an erythropoiesis-stimulating agent.

    PubMed

    Rossert, Jerome; Yue, Susan; Smirnakis, Karen; Mytych, Daniel T; Johnson, Larry; Kouchakji, Elias; Casadevall, Nicole

    2014-02-01

    Antibody-mediated pure red cell aplasia (PRCA) has been primarily observed in patients with chronic kidney disease treated with an erythropoiesis-stimulating agent (ESA); only a few anecdotal cases have been reported in other patient populations. We searched the Amgen Global Safety Adverse Event Database and identified 14 patients with hepatitis C who developed severe anemia, anti-erythropoietin antibodies, and bone marrow biopsy-proven PRCA, while receiving interferon therapy (with or without ribavirin) and an ESA. During the follow-up period and after ESA treatment stopped, 11 patients no longer required transfusions and 3 did. Analysis of antibody isotypes showed that, contrary to reports of patients with chronic kidney disease, immunoglobulin G1 was the predominant isotype rather than immunoglobulin G4 (immunoglobulin G4 was detected in only 1 of 6 patients). Epitope mapping showed the anti-erythropoietin antibodies bound domains required for receptor binding. Therefore, the potential benefits of ESA therapy must be weighed against the risk for PRCA in patients with hepatitis C who are receiving treatment with interferon and ribavirin. Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.

  8. Whole-Body Imaging of High-Dose Ionizing Irradiation-Induced Tissue Injuries Using 99mTc-Duramycin

    PubMed Central

    Johnson, Steven E.; Li, Zhixin; Liu, Yu; Moulder, John E.; Zhao, Ming

    2013-01-01

    High-dose ionizing irradiation can cause extensive injuries in susceptible tissues. A noninvasive imaging technique that detects a surrogate marker of apoptosis may help characterize the dynamics of radiation-induced tissue damage. The goal of this study was to prove the concept of imaging the temporal and spatial distribution of damage in susceptible tissues after high-dose radiation exposure, using 99mTc-duramycin as a phosphatidylethanolamine-binding radiopharmaceutical. Methods Rats were subjected to 15 Gy of total-body irradiation with x-rays. Planar whole-body 99mTc-duramycin scanning (n = 4 per time point) was conducted at 24, 48, and 72 h using a clinical γ-camera. On the basis of findings from planar imaging, preclinical SPECT data were acquired on control rats and on irradiated rats at 6 and 24 h after irradiation (n = 4 per time point). Imaging data were validated by γ-counting and histology, using harvested tissues in parallel groups of animals (n = 4). Results Prominent focal uptake was detected in the thymus as early as 6 h after irradiation, followed by a gradual decline in 99mTc-duramycin binding accompanied by extensive thymic atrophy. Early (6–24 h) radioactivity uptake in the gastrointestinal region was detected. Significant signal was seen in major bones in a slightly delayed fashion, at 24 h, which persisted for at least 2 d. This finding was paralleled by an elevation in signal intensity in the kidneys, spleen, and liver. The imaging results were consistent with ex vivo γ-counting results and histology. Relatively high levels of apoptosis were detected from histology in the thymus, guts, and bones, with the thymus undergoing substantial atrophy. Conclusion As a proof of principle, this study demonstrated a noninvasive imaging technique that allows characterization of the temporal and spatial dynamics of injuries in susceptible tissues during the acute phase after high-dose ionizing irradiation. Such an imaging capability will potentially

  9. UV irradiation-induced methionine oxidation in human skin keratins: Mass spectrometry-based non-invasive proteomic analysis.

    PubMed

    Lee, Seon Hwa; Matsushima, Keita; Miyamoto, Kohei; Oe, Tomoyuki

    2016-02-05

    Ultraviolet (UV) radiation is the major environmental factor that causes oxidative skin damage. Keratins are the main constituents of human skin and have been identified as oxidative target proteins. We have recently developed a mass spectrometry (MS)-based non-invasive proteomic methodology to screen oxidative modifications in human skin keratins. Using this methodology, UV effects on methionine (Met) oxidation in human skin keratins were investigated. The initial screening revealed that Met(259), Met(262), and Met(296) in K1 keratin were the most susceptible oxidation sites upon UVA (or UVB) irradiation of human tape-stripped skin. Subsequent liquid chromatography/electrospray ionization-MS and tandem MS analyses confirmed amino acid sequences and oxidation sites of tryptic peptides D(290)VDGAYMTK(298) (P1) and N(258)MQDMVEDYR(267) (P2). The relative oxidation levels of P1 and P2 increased in a time-dependent manner upon UVA irradiation. Butylated hydroxytoluene was the most effective antioxidant for artifactual oxidation of Met residues. The relative oxidation levels of P1 and P2 after UVA irradiation for 48 h corresponded to treatment with 100mM hydrogen peroxide for 15 min. In addition, Met(259) was oxidized by only UVA irradiation. The Met sites identified in conjunction with the current proteomic methodology can be used to evaluate skin damage under various conditions of oxidative stress. We demonstrated that the relative Met oxidation levels in keratins directly reflected UV-induced damages to human tape-stripped skin. Human skin proteins isolated by tape stripping were analyzed by MS-based non-invasive proteomic methodology. Met(259), Met(262), and Met(296) in K1 keratin were the most susceptible oxidation sites upon UV irradiation. Met(259) was oxidized by only UVA irradiation. Quantitative LC/ESI-SRM/MS analyses confirmed a time-dependent increase in the relative oxidation of target peptides (P1 and P2) containing these Met residues, upon UVA irradiation

  10. Accidental mechanical asphyxia of children in Germany between 2000 and 2008.

    PubMed

    Meyer, F S; Trübner, K; Schöpfer, J; Zimmer, G; Schmidt, E; Püschel, K; Vennemann, M; Bajanowski, T; Althaus, L; Bach, P; Banaschak, S; Cordes, O; Dettmeyer, S R; Dressler, J; Gahr, B; Grellner, W; Héroux, V; Mützel, E; Tatschner, T; Zack, F; Zedler, B

    2012-09-01

    Accidents constitute one of the greatest risks to children, yet there are few medical reports that discuss the subject of accidental asphyxia. However, a systematic analysis of all documented cases in Germany over the years 2000-2008 has now been conducted, aiming at identifying patterns of accidental asphyxia, deducing findings, defining avoidance measures and recommending ways of increasing product safety and taking possible precautions. The analysis is based on a detailed retrospective analysis of all 91 relevant autopsy reports from 24 different German forensic institutes. A variety of demographic and morphological data was systematically collected and analysed. In 84 of the 91 cases, the sex of the victim was reported, resulting in a total of 57 boys (68 %) and 27 girls (32 %). The age spread ranged between 1 day and 14 years, with an average of 5.9 years. Most accidents occurred in the first year of life (20 %) or between the ages of 1 and 2 years (13 %). In 46 % of cases, the cause of death was strangulation, with the majority occurring in the home environment. In 31 % of all cases, the cause of death was positional asphyxia, the majority resulting from chest compression. In 23 % of cases, the cause of death was aspiration, mainly of foreign bodies. Today, accidental asphyxiation is a rare cause of death in children in Germany. Nevertheless, the majority of cases could have been avoided. Future incidence can be reduced by implementing two major precautions: increasing product safety and educating parents of potentially fatal risks. Specific recommendations relate to children's beds, toys and food.

  11. Study of irradiation damage induced by He2+ ion irradiation in Ni62Ta38 metallic glass and W metal

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaonan; Mei, Xianxiu; Zhang, Qi; Li, Xiaona; Wang, Yingmin; Wang, Younian

    2017-09-01

    Metallic glasses are considered to possess good resistant against irradiation due to their inherent structural long-range disorder and a lack of grain boundaries. The He2+ with an energy of 300 keV was used to irradiate Ni62Ta38 binary metallic glass to investigate its resistance against the irradiation, and the irradiated behaviour of the metallic glass was compared with that of W metal. The irradiation fluence range over 2.0 × 1017 ions/cm2-1.6 × 1018 ions/cm2. The TEM results show that nanocrystals of μ-NiTa phase and Ni2Ta phase appeared in Ni62Ta38 metallic glass under the irradiation fluence of 1.6 × 1018 ions/cm2. The SEM results show that the surfaces of Ni62Ta38 metallic glasses maintained flat and smooth, whereas a large area of blisters with peeling formed on the surface of W metal at the irradiation fluence of 1.0 × 1018 ions/cm2. It indicates that the critical irradiation fluence of surface breakage of the Ni62Ta38 metallic glass is higher than that of W metal. After the irradiation, stress was generated in the surface layer of W metal, leading to the increase of the hardness of W metal.

  12. Pump-probe imaging of laser-induced periodic surface structures after ultrafast irradiation of Si

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murphy, Ryan D.; Torralva, Ben; Adams, David P.

    2013-09-30

    Ultrafast pump-probe microscopy has been used to investigate laser-induced periodic surface structure (LIPSS) formation on polished Si surfaces. A crater forms on the surface after irradiation by a 150 fs laser pulse, and a second, subsequent pulse forms LIPSS within the crater. Sequentially delayed images show that LIPSS with a periodicity slightly less than the fundamental laser wavelength of 780 nm appear on Si surfaces ∼50 ps after arrival of the second pump laser pulse, well after the onset of melting. LIPSS are observed on the same timescale as material removal, suggesting that their formation involves material ejection.

  13. Defects induced in cerium dioxide single crystals by electron irradiation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Costantini, Jean-Marc; Miro, Sandrine; Touati, Nadia

    In this work, Micro-Raman spectroscopy, X-band electron paramagnetic resonance (EPR) spectroscopy, and UV-visible optical absorption spectroscopy were used to study the damage production in cerium dioxide (CeO 2) single crystals by electron irradiation for three energies (1.0, 1.4, and 2.5 MeV). The Raman-active T 2g peak was left unchanged after 2.5-MeV electron irradiation at a high fluence. This shows that no structural modifications occurred for the cubic fluorite structure. UV-visible optical absorption spectra exhibited a characteristic sub band-gap tail for 1.4-MeV and 2.5-MeV energies, but not for 1.0 MeV. Narrow EPR lines were recorded near liquid-helium temperature after 2.5-MeV electronmore » irradiation; whereas no such signal was found for the virgin un-irradiated crystal or after 1.0-MeV irradiation for the same fluence. The angular variation of these lines in the {111} plane revealed a weak g-factor anisotropy assigned to Ce 3+ ions (with the 4f 1 configuration) in a high-symmetry local environment. Finally, it is concluded that Ce 3+ ions may be produced by a reduction resulting from the displacement damage process. However, no evidence of F + or F 0 center or hole center formation due to irradiation was found from the present EPR and optical absorption spectra.« less

  14. Defects induced in cerium dioxide single crystals by electron irradiation

    DOE PAGES

    Costantini, Jean-Marc; Miro, Sandrine; Touati, Nadia; ...

    2018-01-12

    In this work, Micro-Raman spectroscopy, X-band electron paramagnetic resonance (EPR) spectroscopy, and UV-visible optical absorption spectroscopy were used to study the damage production in cerium dioxide (CeO 2) single crystals by electron irradiation for three energies (1.0, 1.4, and 2.5 MeV). The Raman-active T 2g peak was left unchanged after 2.5-MeV electron irradiation at a high fluence. This shows that no structural modifications occurred for the cubic fluorite structure. UV-visible optical absorption spectra exhibited a characteristic sub band-gap tail for 1.4-MeV and 2.5-MeV energies, but not for 1.0 MeV. Narrow EPR lines were recorded near liquid-helium temperature after 2.5-MeV electronmore » irradiation; whereas no such signal was found for the virgin un-irradiated crystal or after 1.0-MeV irradiation for the same fluence. The angular variation of these lines in the {111} plane revealed a weak g-factor anisotropy assigned to Ce 3+ ions (with the 4f 1 configuration) in a high-symmetry local environment. Finally, it is concluded that Ce 3+ ions may be produced by a reduction resulting from the displacement damage process. However, no evidence of F + or F 0 center or hole center formation due to irradiation was found from the present EPR and optical absorption spectra.« less

  15. Detection of low amount of irradiated ingredients in non-irradiated precooked meals

    NASA Astrophysics Data System (ADS)

    Marchioni, Eric; Horvatovich, Peter; Ndiaye, Bara; Miesch, Michel; Hasselmann, Claude

    2002-03-01

    The application of the European Standards for the detection of irradiated food by thermoluminescence of silicates, electron-spin resonance spectroscopy of bones or gas chromatography-mass spectrometry of 2-alkylcyclobutanones does not allow the detection of irradiated ingredients included in small quantity in the matrix of a food which has not been irradiated, but which could be subjected to various processing technologies such as cooking, freezing or storage. The use of an enzymatic food hydrolysis carried out at moderated temperature, for the extraction of the food-contaminating silicate minerals and bone fragments, followed by a purification of the extracts by a high-density aqueous solution of sodium polytungstate, allows a simultaneous detection of weak inclusions (0.1% m:m) of irradiated spices and mechanically deboned turkey meat (MRM) included in various precooked foods. Moreover, the use of a supercritical fluid extraction procedure for the 2-alkylcyclobutanones or an additional purification step of the lipid extracts made it possible to lower the detection limit of the 2-alkylcyclobutanones radiation-induced from triglycerides. Using gas chromatography-mass spectrometry, down to 0.5% (m:m) of irradiated MRM included in non-irradiated chicken quenelles could be detected.

  16. Correlation of proton irradiation induced threshold voltage shifts to deep level traps in AlGaN/GaN heterostructures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Z.; Cardwell, D.; Sasikumar, A.

    2016-04-28

    The impact of proton irradiation on the threshold voltage (V{sub T}) of AlGaN/GaN heterostructures is systematically investigated to enhance the understanding of a primary component of the degradation of irradiated high electron mobility transistors. The value of V{sub T} was found to increase monotonically as a function of 1.8 MeV proton fluence in a sub-linear manner reaching 0.63 V at a fluence of 1 × 10{sup 14} cm{sup −2}. Silvaco Atlas simulations of V{sub T} shifts caused by GaN buffer traps using experimentally measured introduction rates, and energy levels closely match the experimental results. Different buffer designs lead to different V{sub T} dependences on protonmore » irradiation, confirming that deep, acceptor-like defects in the GaN buffer are primarily responsible for the observed V{sub T} shifts. The proton irradiation induced V{sub T} shifts are found to depend on the barrier thickness in a linear fashion; thus, scaling the barrier thickness could be an effective way to reduce such degradation.« less

  17. Irradiation-induced microstructural evolution and mechanical properties in iron with and without helium

    NASA Astrophysics Data System (ADS)

    Okuniewski, Maria Ann

    Ferritic-martensitic steels have been identified as candidate structural materials for Generation IV reactors, fusion systems, and accelerator driven systems (ADS). These steels have been selected because of their superior radiation resistance to void swelling, irradiation creep, and helium (He) and hydrogen (H) embrittlement at higher temperatures (T/Tm > 0.4). In fusion and ADS reactors the structural materials will be subjected to irradiation damage, as well as the introduction of He and H. The He and H can be introduced via (n,alpha) and (n,p) threshold reactions, respectively. Also protons can be directly implanted from the beam in an ADS. In fusion and ADS environments the He generation is approximately 10 appm/dpa and 150 appm/dpa. The H generation is approximately three to ten times higher than He production in ADS environments. The impact of these large generation rates of He and H impurities on microstructural evolution during irradiation is not well understood. The irradiation-induced microstructural evolution and its relationship to mechanical properties in body-centered cubic (bcc) iron (Fe) with and without He was systematically investigated. The bcc Fe was selected as a simplified material to serve as a basis for a reactor structural material that was exposed to varying He-to-damage ratios to simulate fusion (10 appm/dpa) and ADS (150 appm/dpa) environments. Through utilizing relatively pure, single crystal, bcc Fe, microstructural and mechanical properties effects from alloying elements can be reduced, if not eliminated. Ion irradiations were carried out at two temperature regimes (300 and 450°C). A coordinated group of experiments and simulations were carried out. Following specimen irradiations, the resultant microstructure and mechanical properties were evaluated with both non-destructive and destructive experimental techniques. The experimental techniques included positron annihilation spectroscopy (PAS), specifically, Doppler broadening

  18. Ion irradiation-induced easy-cone anisotropy in double-MgO free layers for perpendicular magnetic tunnel junctions

    NASA Astrophysics Data System (ADS)

    Teixeira, B. M. S.; Timopheev, A. A.; Caçoilo, N. F. F.; Auffret, S.; Sousa, R. C.; Dieny, B.; Alves, E.; Sobolev, N. A.

    2018-05-01

    We have used the ferromagnetic resonance in the X-band (9.37 GHz) to investigate the effect of 400 keV Ar+ irradiation on the perpendicular magnetic anisotropy (PMA) and Gilbert damping parameter, α, of double-MgO free layers designed for application in perpendicular magnetic tunnel junctions. The samples comprised a MgO/Fe72Co8B20/X(0.2 nm)/Fe72Co8B20/MgO layer stack, where X stands for an ultrathin Ta or W spacer. Samples with two different total FeCoB layer thicknesses, tFCB = 3.0 nm and tFCB = 2.6 nm, were irradiated with ion fluences ranging from 1012 cm-2 to 1016 cm-2. The effective first-order PMA field, BK1, decreased nearly linearly with the logarithm of the fluence for both FeCoB thicknesses and spacer elements. The decrease in BK1, which is likely caused by an ion-induced intermixing at the FeCoB/MgO interfaces, resulted in a reorientation of the magnetization of the free layers with tFCB = 2.6 nm, initially exhibiting a perpendicular easy-axis anisotropy. For intermediate fluences, 1013 cm-2 and 1014 cm-2, easy-cone states with different cone angles could be induced in the free layer with a W spacer. Importantly, no corresponding increase in the Gilbert damping was observed. This study shows that ion irradiation can be used to tune the easy-cone anisotropy in perpendicular magnetic tunnel junctions, which is interesting for spintronic applications such as spin-torque magnetic memory devices, oscillators, and sensors.

  19. [Cardiac arrest due to accidental hypothermia and prolonged cardiopulmonary resuscitation].

    PubMed

    Kot, P; Botella, J

    2010-11-01

    In cardiac arrest produced by accidental hypothermia, cardiopulmonary resuscitation must be prolonged until normal body temperature is achieved. There are different rewarming methods. In theory, the more invasive ones are elective in patients with cardiac arrest because of their higher rewarming speed. However, it has not been proven that these methods are better than the non-invasive ones. We present a case report of a patient with cardiac arrest due to accidental hypothermia who was treated without interruption for three hours with heart massage. This is the longest successful cardiopulmonary resuscitation known up-to-date in Spain. In order to rewarm the body, a combination of non-invasive methods was used: active external rewarming with convective warm air, gastric and bladder lavage with warm saline solution and intravenous warm saline infusion. This case shows that it is possible to treat hypothermic cardiac arrest successfully through these rewarming methods, which are both easy to apply and feasible in any hospital. Copyright © 2009 Elsevier España, S.L. y SEMICYUC. All rights reserved.

  20. RITA enhances irradiation-induced apoptosis in p53-defective cervical cancer cells via upregulation of IRE1α/XBP1 signaling.

    PubMed

    Zhu, Hong; Abulimiti, Muyasha; Liu, Huan; Su, Xiang-Jiang; Liu, Cai-Hong; Pei, Hai-Ping

    2015-09-01

    Radiation therapy is the most widely used treatment for patients with cervical cancer. Recent studies have shown that endoplasmic reticulum (ER) stress induces apoptosis and sensitizes tumor cells to radiotherapy, which reportedly induces ER stress in cells. Classical key tumor suppressor p53 is involved in the response to a variety of cellular stresses, including those incurred by ionizing irradiation. A recent study demonstrated that small-molecule RITA (reactivation of p53 and induction of tumor cell apoptosis) increased the radiosensitivity of tumor cells expressing mutant p53 (mtp53). In the present study, we explored the effects and the underlying mechanisms of RITA in regards to the radiosensitivity and ER stress in mtp53-expressing human cervix cancer cells. Treatment with 1 µM of RITA for 24 h before irradiation markedly decreased survival and increased apoptosis in C-33A and HT-3 cells; the effects were not significantly altered by knockdown of p53. In the irradiated C-33A and HT-3 cells, RITA significantly increased the expression of IRE1α, the spliced XBP1 mRNA level, as well as apoptosis; the effects were abolished by knockdown of IRE1α. Transcriptional pulse-chase assays revealed that RITA significantly increased the stability of IRE1α mRNA in the irradiated C-33A and HT-3 cells. In contrast, the same RITA treatment did not show any significant effect on sham-irradiated cells. In conclusion, the present study provides initial evidence that RITA upregulates the expression level of IRE1α by increasing the stability of IRE1α mRNA in irradiated mtp53-expressing cervical cancer cells; the effect leads to enhanced IRE1α/XBP1 ER stress signaling and increased apoptosis in the cells. The present study offers novel insight into the pharmacological potential of RITA in the radiotherapy for cervical cancer.

  1. Gamma-irradiation enhances apoptosis induced by cannabidiol, a non-psychotropic cannabinoid, in cultured HL-60 myeloblastic leukemia cells.

    PubMed

    Gallily, Ruth; Even-Chena, Tal; Katzavian, Galia; Lehmann, Dan; Dagan, Arie; Mechoulam, Raphael

    2003-10-01

    Two non-psychotropic cannabinoids, cannabidiol (CBD) and cannabidiol-dimethylheptyl (CBD-DMH), induced apoptosis in a human acute myeloid leukemia (AML) HL-60 cell line. Apoptosis was determined by staining with bisBenzimide and propidium iodide. A dose dependent increase of apoptosis was noted, reaching 61 and 43% with 8 microg/ml CBD and 15 microg/ml CBD-DMH, respectively, after a 24 h treatment. Prior exposure of the cells to gamma-irradiation (800 cGy) markedly enhanced apoptosis, reaching values of 93 and 95%, respectively. Human monocytes from normal individuals were resistant to either cannabinoids or gamma-irradiation. Caspase-3 activation was observed after the cannabinoid treatment, and may represent a mechanism for the apoptosis. Our data suggest a possible new approach to treatment of AML.

  2. A case of pediatric age anticholinergic intoxication due to accidental Datura stramonium ingestion admitting with visual hallucination.

    PubMed

    Şanlıdağ, Burçin; Derinöz, Okşan; Yıldız, Nagehan

    2014-01-01

    Datura stramonium (DS) is a hallucinogenic plant that can produce anticholinergic toxicity because of its significant concentrations of toxic alkaloids, such as atropine, hyoscyamine, and scopolamine. DS grows in both rural and urban areas in Turkey. Clinical findings of toxicity are similar to those of atropine toxicity. DS abuse is common among adolescents because of its hallucinatory effects. However, accidental DS poisoning from contaminated food is very rare. Accidental poisonings are commonly seen among children. Children are more prone to the toxic effects of atropine; ingestion of even a small amount can cause serious central nervous system symptoms. Treatment is supportive; antidote treatment is given rarely. An eight-year-old male with accidental DS poisoning who presented to the Pediatric Emergency Department with aggression, agitation, delirium, and visual hallucinations is reported.

  3. Runge-Lenz vector, accidental SU(2) symmetry, and unusual multiplets for motion on a cone

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Al-Hashimi, M.H.; Wiese, U.-J.

    2008-01-15

    We consider a particle moving on a cone and bound to its tip by 1/r or harmonic oscillator potentials. When the deficit angle of the cone divided by 2{pi} is a rational number, all bound classical orbits are closed. Correspondingly, the quantum system has accidental degeneracies in the discrete energy spectrum. An accidental SU(2) symmetry is generated by the rotations around the tip of the cone as well as by a Runge-Lenz vector. Remarkably, some of the corresponding multiplets have fractional 'spin' and unusual degeneracies.

  4. Immunization against strontium-90 induction of bone tumors with inactivated FBJ virus and irradiated syngeneic strontium-90-induced tumor cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reif, A.E.; Triest, W.E.

    1981-01-01

    Three hundred six C57BL/6J female mice were subdivided into a control group left untreated and an experimental group treated intraperitoneally with 1.0 ..mu..Ci strontium-90/g of body weight at an age of 66 days. Treatments for the groups were as follows: none, 6 injections of formalin-inactivated FBJ viral preparation, 6 injections of active FBJ viral preparation, and 2 injections of 10,000 rad irradiated transplantable osteosarcoma previously induced in C57BL/6J mice by strontium-90. In addition to the above groups, two other groups were treated with respectively 0.032 and 0.10 ..mu..Ci strontium-90/g body weight in order to obtain information on the dose-response relationshipmore » between the injection of strontium-90 and the yield of bone tumors. In the groups not treated with strontium-90, only 1 bone tumor developed; this occurred in the group injected with FBJ virus. The incidence of bone tumors in the groups treated with 1.0 ..mu..Ci strontium-90 was significantly lower (18.5% or 18.2%) in the two groups that had received injections of inactivated FBJ virus or irradiated isogenic osteosarcoma when compared to the group left uninjected, which developed 43.5% tumors. In contrast, the strontium-90-treated group that also received injections of active FBJ virus developed 63.0% tumors. Only a single bone tumor developed in the groups treated solely with intermediate doses of strontium-90. The results indicate that immunization with inactivated FBJ virus or with irradiated syngeneic strontium-90-induced tumor cells can significantly decrease the development of strontium-90-induced tumors.« less

  5. Trauma-induced systemic inflammatory response versus exercise-induced immunomodulatory effects.

    PubMed

    Fehrenbach, Elvira; Schneider, Marion E

    2006-01-01

    Accidental trauma and heavy endurance exercise, both induce a kind of systemic inflammatory response, also called systemic inflammatory response syndrome (SIRS). Exercise-related SIRS is conditioned by hyperthermia and concomitant heat shock responses, whereas trauma-induced SIRS manifests concomitantly with tissue necrosis and immune activation, secondarily followed by fever. Inflammatory cytokines are common denominators in both trauma and exercise, although there are marked quantitative differences. Different anti-inflammatory cytokines may be involved in the control of inflammation in trauma- and exercise-induced stress. Exercise leads to a balanced equilibrium between inflammatory and anti-inflammatory responses. Intermittent states of rest, as well as anti-oxidant capacity, are lacking or minor in trauma but are high in exercising individuals. Regular training may enhance immune competence, whereas trauma-induced SIRS often paves the way for infectious complications, such as sepsis.

  6. Accidental poisoning with Veratrum album mistaken for wild garlic (Allium ursinum).

    PubMed

    Gilotta, Irene; Brvar, Miran

    2010-11-01

    Veratrum album (white or false hellebore) is a poisonous plant containing steroidal alkaloids that cause nausea, vomiting, headache, visual disturbances, paresthesia, dizziness, bradycardia, atrioventricular block, hypotension, and syncope. It is regularly mistaken for Gentiana lutea (yellow gentian). We report accidental poisoning with V. album mistaken for Allium ursinum (wild garlic), a wild plant used in soups and salads in Central Europe. Four adults (24-45 years) accidentally ingested V. album mistaken for A. ursinum in self-prepared salads and soups. Within 15-30 min of ingestion they developed nausea, vomiting, and abdominal pain. At the same time dizziness, tingling, dimmed and jumping vision, transient blindness, and confusion appeared. On arrival at the ED, all patients had sinus bradycardia and hypotension. Following treatment the patients were discharged well 24-48 h after ingestion. In patients presenting with gastrointestinal, neurological, and cardiovascular symptoms a history of wild plant ingestion suggests possible poisoning with V. album mistaken for wild garlic.

  7. Photonic crystal surface-emitting lasers enabled by an accidental Dirac point

    DOEpatents

    Chua, Song Liang; Lu, Ling; Soljacic, Marin

    2014-12-02

    A photonic-crystal surface-emitting laser (PCSEL) includes a gain medium electromagnetically coupled to a photonic crystal whose energy band structure exhibits a Dirac cone of linear dispersion at the center of the photonic crystal's Brillouin zone. This Dirac cone's vertex is called a Dirac point; because it is at the Brillouin zone center, it is called an accidental Dirac point. Tuning the photonic crystal's band structure (e.g., by changing the photonic crystal's dimensions or refractive index) to exhibit an accidental Dirac point increases the photonic crystal's mode spacing by orders of magnitudes and reduces or eliminates the photonic crystal's distributed in-plane feedback. Thus, the photonic crystal can act as a resonator that supports single-mode output from the PCSEL over a larger area than is possible with conventional PCSELs, which have quadratic band edge dispersion. Because output power generally scales with output area, this increase in output area results in higher possible output powers.

  8. Ion-irradiation-induced microstructural modifications in ferritic/martensitic steel T91

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Xiang; Miao, Yinbin; Li, Meimei

    In this paper, in situ transmission electron microscopy investigations were carried out to study the microstructural evolution of ferritic/martensitic steel T91 under 1 MeV Krypton ion irradiation up to 4.2 x 10(15) ions/cm(2) at 573 K, 673 K, and 773 K. At 573 K, grown-in defects are strongly modified by black dot loops, and dislocation networks together with black-dot loops were observed after irradiation. At 673 K and 773 K, grown-in defects are only partially modified by dislocation loops; isolated loops and dislocation segments were commonly found after irradiation. Post irradiation examination indicates that at 4.2 x 1015 ions/cm(2), aboutmore » 51% of the loops were a(0)/2 < 111 > type for the 673 K irradiation, and the dominant loop type was a(0)< 100 > for the 773 K irradiation. Finally, a dispersed barrier hardening model was employed to estimate the change in yield strength, and the calculated ion data were found to follow the similar trend as the existing neutron data with an offset of 100-150 MPa. (C) 2017 Elsevier B.V. All rights reserved.« less

  9. Bittering agents in the prevention of accidental poisoning: children's reactions to denatonium benzoate (Bitrex).

    PubMed Central

    Sibert, J R; Frude, N

    1991-01-01

    The responses of young children to Denatonium Benzoate (Bitrex) were observed, in order to assess the potential of this bittering agent in the prevention of accidental poisoning. Thirty-three children aged 17-36 months were offered orange juice containing Bitrex (in a concentration of 10 parts per million). Of the 30 children who took some of this juice, only seven were willing to take more than 10 gm. A variety of negative verbal and non-verbal responses were noted. It is suggested that the highly unpalatable nature of Bitrex makes this compound a useful additive that could well prevent accidental poisoning from household products of mild to moderate toxicity. PMID:1854387

  10. Apoptosis and accidental cell death in cultured human keratinocytes after thermal injury.

    PubMed

    Matylevitch, N P; Schuschereba, S T; Mata, J R; Gilligan, G R; Lawlor, D F; Goodwin, C W; Bowman, P D

    1998-08-01

    The respective roles of apoptosis and accidental cell death after thermal injury were evaluated in normal human epidermal keratinocytes. By coupling the LIVE/DEAD fluorescence viability assay with the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) method and ultrastructural morphology, these two processes could be distinguished. Cells were grown on glass coverslips with a microgrid pattern so that the results of several staining procedures performed sequentially could be visualized in the same cells after heating at temperatures of up to 72 degrees C for 1 second. After exposure to temperatures of 58 to 59 degrees C, cells died predominantly by apoptosis; viable cells became TUNEL positive, indicating degradation of DNA. After exposure to temperatures of 60 to 66 degrees C, both TUNEL-positive viable cells and TUNEL-positive nonviable cells were observed, indicating that apoptosis and accidental cell death were occurring simultaneously. Cells died almost immediately after exposure to temperatures above 72 degrees C, presumably from heat fixation. The fluorescent mitochondrial probe MitoTracker Orange indicated that cells undergoing apoptosis became TUNEL positive before loss of mitochondrial function. Nucleosomal fragmentation of DNA analyzed by enzyme-linked immunosorbent assay and gel electrophoresis occurred after exposure to temperatures of 58 to 59 degrees C. The characteristic morphological findings of cells undergoing apoptosis, by transmission electron microscopy, included cellular shrinkage, cytoplasmic budding, and relatively intact mitochondria. Depending on temperature and time of exposure, normal human epidermal keratinocytes may die by apoptosis, accidental cell death, or heat fixation.

  11. Radiation-induced degradation of cyclohexanebutyric acid in aqueous solutions by gamma ray irradiation

    NASA Astrophysics Data System (ADS)

    Jia, Wenbao; He, Yanquan; Ling, Yongsheng; Hei, Daqian; Shan, Qing; Zhang, Yan; Li, Jiatong

    2015-04-01

    The radiation-induced degradation of cyclohexanebutyric acid under gamma ray irradiation was investigated. Degradation experiments were performed with 100 mL sealed Pyrex glass vessels loaded with 80 mL of cyclohexanebutyric acid solutions at various initial concentrations of 10, 20, and 40 mg L-1. The absorbed doses were controlled at 0, 0.65, 1.95, 3.25, 6.5, 9.75, and 13 kGy. The results showed that gamma ray irradiation could effectively degrade cyclohexanebutyric acid in aqueous solutions. The removal rate of cyclohexanebutyric acid increased significantly with the increase of absorbed dose and the decrease of its initial concentration. At the same time, the removal of chemical oxygen demand (COD) was as effective as that of cyclohexanebutyric acid. The kinetic studies showed that the degradation of cyclohexanebutyric acid followed pseudo first-order reaction. Above all, the proposed mechanism obtained when NaNO2, NaNO3 and tert-butanol were added showed that the •OH radical played a major role in the gamma degradation process of cyclohexanebutyric acid, while •H and eaq- played a minor role in the gamma degradation process. The degradation products were identified by Fourier transform infrared spectroscopy (FTIR) and gas chromatography/mass spectrometry (GC/MS) during cyclohexanebutyric acid degradation.

  12. Effects of gamma irradiation on deteriorated paper

    NASA Astrophysics Data System (ADS)

    Bicchieri, Marina; Monti, Michela; Piantanida, Giovanna; Sodo, Armida

    2016-08-01

    Even though gamma radiation application, also at the minimum dosage required for disinfection, causes depolymerization and degradation of the paper substrate, recently published papers seemed, instead, to suggest that γ-rays application could be envisaged in some conditions for Cultural Heritage original documents and books. In some of the published papers, the possible application of γ-rays was evaluated mainly by using mechanical tests that scarcely reflect the chemical modifications induced in the cellulosic support. In the present article the effect of low dosage γ-irradiation on cellulosic substrates was studied and monitored applying different techniques: colorimetry, spectroscopic measurements, carbonyl content and average viscometric degree of polymerization. Two different papers were investigated, a non-sized, non-filled cotton paper, and a commercial permanent paper. To simulate a real deteriorated document, which could need γ-rays irradiation, some samples were submitted to a hydrolysis treatment. We developed a treatment based on the exposition of paper to hydrochloric acid vapors, avoiding any contact of the samples with water. This method induces a degradation similar to that observed on original documents. The samples were then irradiated with 3 kGy γ-rays at a 5258 Gy/h rate. The aforementioned analyses were performed on the samples just irradiated and after artificial ageing. All tests showed negative effects of gamma irradiation on paper. Non-irradiated paper preserves better its appearance and chemical properties both in the short term and after ageing, while the irradiated samples show appreciable color change and higher oxidation extent. Since the Istituto centrale restauro e conservazione patrimonio archivistico e librario is responsible for the choice of all restoration treatments that could be applied on library and archival materials under the protection of the Italian State (http://www.icpal.beniculturali.it/allegati/DM-7

  13. Cytosolic Irradiation of Femtosecond Laser Induces Mitochondria-dependent Apoptosis-like Cell Death via Intrinsic Reactive Oxygen Cascades

    PubMed Central

    Yoon, Jonghee; Ryu, Seung-wook; Lee, Seunghee; Choi, Chulhee

    2015-01-01

    High-intensity femtosecond lasers have recently been used to irreversibly disrupt nanoscale structures, such as intracellular organelles, and to modify biological functions in a reversible manner: so-called nanosurgery and biophotomodulation. Femtosecond laser pulses above the threshold intensity sufficient for reversible biophotomodulation can cause irreversible changes in the irradiated cell, eventually leading to cell death. Here, we demonstrated that cytosolic irradiation with a femtosecond laser produced intrinsic cascades of reactive oxygen species (ROS), which led to rapid apoptosis-like cell death via a caspase and poly (ADP-ribose) polymerase 1 (PARP-1) signaling pathway. We further showed that cells with enhanced mitochondrial fusion activity are more resilient to laser-induced stress compared to those with enforced mitochondrial fission. Taken together, these findings provide fundamental insight into how optical stimulation intervenes in intrinsic cellular signaling pathways and functions. PMID:25648455

  14. Cytosolic irradiation of femtosecond laser induces mitochondria-dependent apoptosis-like cell death via intrinsic reactive oxygen cascades.

    PubMed

    Yoon, Jonghee; Ryu, Seung-Wook; Lee, Seunghee; Choi, Chulhee

    2015-02-04

    High-intensity femtosecond lasers have recently been used to irreversibly disrupt nanoscale structures, such as intracellular organelles, and to modify biological functions in a reversible manner: so-called nanosurgery and biophotomodulation. Femtosecond laser pulses above the threshold intensity sufficient for reversible biophotomodulation can cause irreversible changes in the irradiated cell, eventually leading to cell death. Here, we demonstrated that cytosolic irradiation with a femtosecond laser produced intrinsic cascades of reactive oxygen species (ROS), which led to rapid apoptosis-like cell death via a caspase and poly (ADP-ribose) polymerase 1 (PARP-1) signaling pathway. We further showed that cells with enhanced mitochondrial fusion activity are more resilient to laser-induced stress compared to those with enforced mitochondrial fission. Taken together, these findings provide fundamental insight into how optical stimulation intervenes in intrinsic cellular signaling pathways and functions.

  15. Accumulation of flavonoids and related compounds in birch induced by UV-B irradiance.

    PubMed

    Lavola, Anu

    1998-01-01

    A growth chamber experiment was conducted to examine the effects of UV-B exposure (4.9 kJ m(-2) day(-1) of biologically effective UV-B, 280-320 nm) on shoot growth and secondary metabolite production in Betula pendula (Roth) and B. resinifera (Britt.) seedlings originating from environments in Finland, Germany and Alaska differing in solar UV-B radiation and climate. Neither shoot growth nor the composition of secondary metabolites was affected by UV-B irradiance, but the treatment induced significant changes in the amounts of individual secondary metabolites in leaves. Leaves of seedlings exposed to UV-B radiation contained higher concentrations of several flavonoids, condensed tannins and some hydroxycinnamic acids than leaves of control seedlings that received no UV-B radiation. At the population level, there was considerable variation in secondary metabolite responses to UV-B radiation: among populations, the induced response was most prominent in Alaskan populations, which were adapted to the lowest ambient UV-B radiation environment. I conclude that solar UV-B radiation plays an important role in the formation of secondary chemical characteristics in birch trees.

  16. Response under low-energy electron irradiation of a thin film of a potential copper precursor for focused electron beam induced deposition (FEBID)

    PubMed Central

    Sala, Leo; Szymańska, Iwona B; Dablemont, Céline; Lafosse, Anne

    2018-01-01

    Background: Focused electron beam induced deposition (FEBID) allows for the deposition of free standing material within nanometre sizes. The improvement of the technique needs a combination of new precursors and optimized irradiation strategies to achieve a controlled fragmentation of the precursor for leaving deposited material of desired composition. Here a new class of copper precursors is studied following an approach that probes some surface processes involved in the fragmentation of precursors. We use complexes of copper(II) with amines and perfluorinated carboxylate ligands that are solid and stable under ambient conditions. They are directly deposited on the surface for studying the fragmentation with surface science tools. Results: Infrared spectroscopy and high-resolution electron energy loss spectroscopy (HREELS) are combined to show that the precursor is able to spontaneously lose amine ligands under vacuum. This loss can be enhanced by mild heating. The combination of mass spectrometry and low-energy electron irradiation (0–15 eV) shows that full amine ligands can be released upon irradiation, and that fragmentation of the perfluorinated ligands is induced by electrons of energy as low as 1.5 eV. Finally, the cross section for this process is estimated from the temporal evolution in the experiments on electron-stimulated desorption (ESD). Conclusion: The release of full ligands under high vacuum and by electron irradiation, and the cross section measured here for ligands fragmentation allow one to envisage the use of the two precursors for FEBID studies. PMID:29379701

  17. Measurement of Heavy Ion Irradiation Induced In-Plane Strain in Patterned Face-Centered-Cubic Metal Films: An in Situ Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yu, K. Y.; Chen, Y.; Li, J.

    Nanocrystalline Ag, Cu, and Ni thin films and their coarse grained counterparts are patterned in this paper using focused ion beam and then irradiated by Kr ions within an electron microscope at room temperature. Irradiation induced in-plane strain of the films is measured by tracking the location of nanosized holes. The magnitude of the strain in all specimens is linearly dose-dependent and the strain rates of nanocrystalline metals are significantly greater as compared to that of the coarse grained metals. Finally, real-time microscopic observation suggests that substantial grain boundary migration and grain rotation are responsible for the significant in-plane strain.

  18. Measurement of Heavy Ion Irradiation Induced In-Plane Strain in Patterned Face-Centered-Cubic Metal Films: An in Situ Study

    DOE PAGES

    Yu, K. Y.; Chen, Y.; Li, J.; ...

    2016-11-28

    Nanocrystalline Ag, Cu, and Ni thin films and their coarse grained counterparts are patterned in this paper using focused ion beam and then irradiated by Kr ions within an electron microscope at room temperature. Irradiation induced in-plane strain of the films is measured by tracking the location of nanosized holes. The magnitude of the strain in all specimens is linearly dose-dependent and the strain rates of nanocrystalline metals are significantly greater as compared to that of the coarse grained metals. Finally, real-time microscopic observation suggests that substantial grain boundary migration and grain rotation are responsible for the significant in-plane strain.

  19. PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC. VOLUME 2. CONTROL OF ACCIDENTAL RELEASES OF CHLORINE (SCAQMD) (SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT)

    EPA Science Inventory

    The manual discusses reducing the risk associated with an accidental release of chlorine. It identifies some of the potential causes of accidental releases that apply to the processes that use chlorine. It also identifies examples of potential causes, as well as measures that may...

  20. Correlation of radiation-induced changes in microstructure/microchemistry, density and thermo-electric power of type 304L and 316 stainless steels irradiated in the Phénix reactor

    NASA Astrophysics Data System (ADS)

    Renault Laborne, Alexandra; Gavoille, Pierre; Malaplate, Joël; Pokor, Cédric; Tanguy, Benoît

    2015-05-01

    Annealed specimens of type 304L and 316 stainless steel and cold-worked 316 specimens were irradiated in the Phénix reactor in the temperature range 381-394 °C and to different damage doses up to 39 dpa. The microstructure and microchemistry of both 304L and 316 have been examined using the combination of the different techniques of TEM to establish the void swelling and precipitation behavior under neutron irradiation. TEM observations are compared with results of measurements of immersion density and thermo-electric power obtained on the same irradiated stainless steels. The similarities and differences in their behavior on different scales are used to understand the factors in terms of the chemical composition and metallurgical state of steels, affecting the precipitation under irradiation and the swelling behavior. Irradiation induces the formation of some precipitate phases (e.g., M6C and M23C6-type carbides, and γ'- and G-phases), Frank loops and cavities. According to the metallurgical state and chemical composition of the steel, the amount of each type of radiation-induced defects is not the same, affecting their density and thermo-electric power.