Science.gov

Sample records for radiation-induced brachial plexopathy

  1. Distinction between neoplastic and radiation-induced brachial plexopathy, with emphasis on the role of EMG

    SciTech Connect

    Harper, C.M. Jr.; Thomas, J.E.; Cascino, T.L.; Litchy, W.J.

    1989-04-01

    The results of clinical, radiologic, and electrophysiologic studies are retrospectively reviewed for 55 patients with neoplastic and 35 patients with radiation-induced brachial plexopathy. The presence or absence of pain as the presenting symptom, temporal profile of the illness, presence of a discrete mass on CT of the plexus, and presence of myokymic discharges on EMG contributed significantly to the prediction of the underlying cause of the brachial plexopathy. The distribution of weakness and the results of nerve conduction studies were of no help in distinguishing neoplastic from radiation-induced brachial plexopathy.

  2. Brachial plexopathy

    MedlinePlus

    ... the muscles Weakness of hand flexing A detailed history may help determine the cause of the brachial plexopathy. Age and sex are important, because some brachial plexus problems are more common in certain groups. For example, young men more often have inflammatory or post-viral ...

  3. Brachial plexopathy

    PubMed Central

    Khadilkar, Satish V.; Khade, Snehaldatta S.

    2013-01-01

    Brachial plexus injury can occur as a result of trauma, inflammation or malignancies, and associated complications. The current topic is concerned with various forms of brachial plexopathy, its clinical features, pathophysiology, imaging findings, and management. Idiopathic brachial neuritis (IBN), often preceded with antecedent events such as infection, commonly present with abruptonset painful asymmetric upper limb weakness with associated wasting around the shoulder girdle and arm muscles. Idiopathic hypertrophic brachial neuritis, a rare condition, is usually painless to begin with, unlike IBN. Hereditary neuralgic amyotrophy is an autosomal-dominant disorder characterized by repeated episodes of paralysis and sensory disturbances in an affected limb, which is preceded by severe pain. While the frequency of the episodes tends to decrease with age, affected individuals suffer from residual deficits. Neurogenic thoracic outlet syndrome affects the lower trunk of the brachial plexus. It is diagnosed on the basis of electrophysiology and is amenable to surgical intervention. Cancer-related brachial plexopathy may occur secondary to metastatic infiltration or radiation therapy. Traumatic brachial plexus injury is commonly encountered in neurology, orthopedic, and plastic surgery set-ups. Trauma may be a direct blow or traction or stretch injury. The prognosis depends on the extent and site of injury as well as the surgical expertise. PMID:23661957

  4. Radiation-induced brachial plexopathy: Neurological follow-up in 161 recurrence-free breast cancer patients

    SciTech Connect

    Olsen, N.K.; Pfeiffer, P.; Johannsen, L.; Schroder, H.; Rose, C. )

    1993-04-30

    The purpose was to assess the incidence and clinical manifestations of radiation-induced brachial plexopathy in breast cancer patients, treated according to the Danish Breast Cancer Cooperative Group protocols. One hundred and sixty-one recurrence-free breast cancer patients were examined for radiation-induced brachial plexopathy after a median follow-up period of 50 months (13-99 months). After total mastectomy and axillary node sampling, high-risk patients were randomized to adjuvant therapy. One hundred twenty-eight patients were treated with postoperative radiotherapy with 50 Gy in 25 daily fractions over 5 weeks. In addition, 82 of these patients received cytotoxic therapy (cyclophosphamide, methotrexate, and 5-fluorouracil) and 46 received tamoxifen. Five percent and 9% of the patients receiving radiotherapy had disabling and mild radiation-induced brachial plexopathy, respectively. Radiation-induced brachial plexopathy was more frequent in patients receiving cytotoxic therapy (p = 0.04) and in younger patients (p = 0.04). The clinical manifestations were paraesthesia (100%), hypaesthesia (74%), weakness (58%), decreased muscle stretch reflexes (47%), and pain (47%). The brachial plexus is more vulnerable to large fraction size. Fractions of 2 Gy or less are advisable. Cytotoxic therapy adds to the damaging effect of radiotherapy. Peripheral nerves in younger patients seems more vulnerable. Radiation-induced brachial plexopathy occurs mainly as diffuse damage to the brachial plexus. 24 refs., 9 tabs.

  5. Dose Constraints to Prevent Radiation-Induced Brachial Plexopathy in Patients Treated for Lung Cancer

    SciTech Connect

    Amini, Arya; Yang Jinzhong; Williamson, Ryan; McBurney, Michelle L.; Erasmus, Jeremy; Allen, Pamela K.; Karhade, Mandar; Komaki, Ritsuko; Liao, Zhongxing; Gomez, Daniel; Cox, James; Dong, Lei; Welsh, James

    2012-03-01

    Purpose: As the recommended radiation dose for non-small-cell lung cancer (NSCLC) increases, meeting dose constraints for critical structures like the brachial plexus becomes increasingly challenging, particularly for tumors in the superior sulcus. In this retrospective analysis, we compared dose-volume histogram information with the incidence of plexopathy to establish the maximum dose tolerated by the brachial plexus. Methods and Materials: We identified 90 patients with NSCLC treated with definitive chemoradiation from March 2007 through September 2010, who had received >55 Gy to the brachial plexus. We used a multiatlas segmentation method combined with deformable image registration to delineate the brachial plexus on the original planning CT scans and scored plexopathy according to Common Terminology Criteria for Adverse Events version 4.03. Results: Median radiation dose to the brachial plexus was 70 Gy (range, 56-87.5 Gy; 1.5-2.5 Gy/fraction). At a median follow-up time of 14.0 months, 14 patients (16%) had brachial plexopathy (8 patients [9%] had Grade 1, and 6 patients [7%] had Grade {>=}2); median time to symptom onset was 6.5 months (range, 1.4-37.4 months). On multivariate analysis, receipt of a median brachial plexus dose of >69 Gy (odds ratio [OR] 10.091; 95% confidence interval [CI], 1.512-67.331; p = 0.005), a maximum dose of >75 Gy to 2 cm{sup 3} of the brachial plexus (OR, 4.909; 95% CI, 0.966-24.952; p = 0.038), and the presence of plexopathy before irradiation (OR, 4.722; 95% CI, 1.267-17.606; p = 0.021) were independent predictors of brachial plexopathy. Conclusions: For lung cancers near the apical region, brachial plexopathy is a major concern for high-dose radiation therapy. We developed a computer-assisted image segmentation method that allows us to rapidly and consistently contour the brachial plexus and establish the dose limits to minimize the risk of brachial plexopathy. Our results could be used as a guideline in future prospective

  6. Brachial plexopathy: recurrent cancer or radiation

    SciTech Connect

    Lederman, R.J.; Wilbourn, A.J.

    1984-10-01

    We reviewed clinical and electrodiagnostic features of 16 patients with neoplastic brachial plexopathy (NBP) and 17 patients with radiation-induced plexopathy (RBP). The groups were similar in symptom-free interval after cancer diagnosis and location of the plexus lesions. NBP patients had pain and Horner's syndrome; RBP patients had paresthesias, but rarely Horner's. NBP patients presented earlier after symptom onset and had a shorter course. RBP patients more frequently had abnormal sensory and normal motor nerve conduction studies and characteristically had fasciculations or myokymia on EMG.

  7. Brachial plexopathy as a rare presenting manifestation of scorpion envenomation.

    PubMed

    Rubin, Devon I; Vavra, Michael

    2011-07-01

    We report a patient who experienced a rare manifestation of an acute, severe brachial plexopathy as the initial complication of scorpion (presumed Hemiscorpius lepturus species) envenomation. Features suggesting conduction block, due to either proximal demyelination or ion channel dysfunction, along with axonal loss were seen on serial electrophysiological studies. Possible mechanisms of the brachial plexopathy include direct compression from tissue edema or a toxic effect on the membrane channels along the nerve.

  8. Shoulder pain and isolated brachial plexopathy

    PubMed Central

    Kishan, Amar U; Syed, Sana; Fiorito-Torres, Franchesca; Thakore-James, Manisha

    2012-01-01

    Pancoast syndrome, classically considered as a constellation of (1) pain along the C8–T2 dermatomes, (2) weakness and atrophy of the hand and (3) Horner's syndrome, often presents a diagnostic challenge. In fact, it may manifest as a singular orthopaedic complaint, prompting a futile barrage of tests and referrals. The authors present the case of an elderly man who initially presented with severe shoulder pain. Due to progressive pain and weakness, he was referred to rheumatology and was treated with corticosteroid injections for a presumed musculoskeletal lesion. Ultimately, he manifested gross muscular atrophy and worsening pain, prompting a referral to neurology. An electromyogram (EMG) suggested a lower brachial plexopathy, and a follow-up brachial plexus MRI identified a large Pancoast tumour. Unfortunately, his disease was rapidly progressive, and he passed away within 2 months. While the MRI remains the gold standard for diagnosing Pancoast syndrome, an EMG can facilitate diagnosis in difficult cases such as this one. PMID:22744250

  9. Magnetic resonance imaging of traumatic and non-traumatic brachial plexopathies

    PubMed Central

    Fan, Yiru Lorna; Othman, Mohamad Isham Bin; Dubey, Niraj; Peh, Wilfred CG

    2016-01-01

    Adult-onset brachial plexopathy can be classified into traumatic and non-traumatic aetiologies. Traumatic brachial plexopathies can affect the pre- or postganglionic segments of the plexus. Non-traumatic brachial plexopathies may be due to neoplasia, radiotherapy, thoracic outlet syndrome and idiopathic neuralgic amyotrophy. Conventional magnetic resonance imaging (MRI) is useful to localise the area of injury or disease, and identify the likely cause. This review discusses some of the common causes of adult-onset brachial plexopathy and their imaging features on MRI. We also present a series of cases to illustrate some of these causes and their MRI findings. PMID:27779278

  10. Brachial Plexopathy in Apical Non-Small Cell Lung Cancer Treated With Definitive Radiation: Dosimetric Analysis and Clinical Implications

    SciTech Connect

    Eblan, Michael J.; Corradetti, Michael N.; Lukens, J. Nicholas; Xanthopoulos, Eric; Mitra, Nandita; Christodouleas, John P.; Grover, Surbhi; Fernandes, Annemarie T.; Langer, Corey J.; Evans, Tracey L.; Stevenson, James; Rengan, Ramesh; Apisarnthanarax, Smith

    2013-01-01

    Purpose: Data are limited on the clinical significance of brachial plexopathy in patients with apical non-small cell lung cancers (NSCLC) treated with definitive radiation therapy. We report the rates of radiation-induced brachial plexopathy (RIBP) and tumor-related brachial plexopathy (TRBP) and associated dosimetric parameters in apical NSCLC patients. Methods and Materials: Charts of NSCLC patients with primary upper lobe or superiorly located nodal disease who received {>=}50 Gy of definitive conventionally fractionated radiation or chemoradiation were retrospectively reviewed for evidence of brachial plexopathy and categorized as RIBP, TRBP, or trauma-related. Dosimetric data were gathered on ipsilateral brachial plexuses (IBP) contoured according to Radiation Therapy Oncology Group atlas guidelines. Results: Eighty patients were identified with a median follow-up and survival time of 17.2 and 17.7 months, respectively. The median prescribed dose was 66.6 Gy (range, 50.4-84.0), and 71% of patients received concurrent chemotherapy. RIBP occurred in 5 patients with an estimated 3-year rate of 12% when accounting for competing risk of death. Seven patients developed TRBP (estimated 3-year rate of 13%), comprising 24% of patients who developed locoregional failures. Grade 3 brachial plexopathy was more common in patients who experienced TRBP than RIBP (57% vs 20%). No patient who received {<=}78 Gy to the IBP developed RIBP. On multivariable competing risk analysis, IBP V76 receiving {>=}1 cc, and primary tumor failure had the highest hazard ratios for developing RIBP and TRBP, respectively. Conclusions: RIBP is a relatively uncommon complication in patients with apical NSCLC tumors receiving definitive doses of radiation, while patients who develop primary tumor failures are at high risk for developing morbid TRBP. These findings suggest that the importance of primary tumor control with adequate doses of radiation outweigh the risk of RIBP in this population of

  11. Lightning strike-induced brachial plexopathy.

    PubMed

    Bhargava, Amita N; Kasundra, Gaurav M; Khichar, Subhakaran; Bhushan, Bharat S K

    2014-10-01

    We describe a patient who presented with a history of lightning strike injury. Following the injury, he sustained acute right upper limb weakness with pain. Clinically, the lesion was located to the upper and middle trunk of the right brachial plexus, and the same confirmed with electrophysiological studies. Nerve damage due to lightning injuries is considered very rare, and a plexus damage has been described infrequently, if ever. Thus, the proposed hypothesis that lightning rarely causes neuropathy, as against high-voltage electric current, due to its shorter duration of exposure not causing severe burns which lead to nerve damage, needs to be reconsidered.

  12. Lightning strike-induced brachial plexopathy

    PubMed Central

    Bhargava, Amita N.; Kasundra, Gaurav M.; Khichar, Subhakaran; Bhushan, Bharat S. K.

    2014-01-01

    We describe a patient who presented with a history of lightning strike injury. Following the injury, he sustained acute right upper limb weakness with pain. Clinically, the lesion was located to the upper and middle trunk of the right brachial plexus, and the same confirmed with electrophysiological studies. Nerve damage due to lightning injuries is considered very rare, and a plexus damage has been described infrequently, if ever. Thus, the proposed hypothesis that lightning rarely causes neuropathy, as against high-voltage electric current, due to its shorter duration of exposure not causing severe burns which lead to nerve damage, needs to be reconsidered. PMID:25288846

  13. Hereditary Neuropathy with Liability to Pressure Palsy Presenting as an Acute Brachial Plexopathy: A Lover's Palsy

    PubMed Central

    Wedderburn, Sarah; Pateria, Puraskar; Panegyres, Peter K.

    2014-01-01

    It is generally regarded that patients with hereditary neuropathy to pressure palsies, due to a deletion in the PMP22 gene, show recurrent pressure palsy and generalised peripheral neuropathy (pes cavus and hammer toes sometimes develop). Brachial plexopathy is rarely identified as a first presentation of hereditary neuropathy to pressure palsies. We describe a young man who developed a painless flail upper limb with a clinical diagnosis of a brachial plexopathy after his partner slept on his arm – a PMP22 deletion was found. His father, who had a symmetrical polyneuropathy without recurrent mononeuropathies, shared the PMP22 deletion. PMID:25685136

  14. Mediastinal mass and brachial plexopathy caused by subclavian arterial aneurysm in Behçet's disease.

    PubMed

    Yoo, W H; Kim, H K; Park, J H; Park, T S; Baek, H S

    2000-01-01

    Vascular involvement in Behçet's disease is divided into venous and arterial thrombosis and arterial aneurysmal formation. Subclavian arterial aneurysm rarely occurs in Behçet's disease; however, when it does occur, it causes serious aneurysmal rupture and local complications such as nerve compression and arterial ischemia. We describe the case of a 39-year-old male who presented with neurologic symptoms and signs of brachial plexopathy and mediastinal mass caused by Behçet's subclavian arterial aneurysm. This case shows that the occurrence of brachial plexopathy should be considered a manifestation of Behçet's disease, and that Behçet's aneurysm should be considered in the differential diagnosis of upper mediastinal mass.

  15. Characteristic features of hereditary neuropathy with liability to pressure palsy (HNPP) presenting with brachial plexopathy in soldiers.

    PubMed

    Kim, Kyoung-Eun

    2014-11-15

    A brachial plexus lesion is not common in hereditary neuropathy with liability to pressure palsy (HNPP). We report the clinical and electrodiagnostic features of young soldiers with HNPP presenting with brachial plexopathy. By reviewing 2year medical records from Korean military hospitals, we identified soldiers with brachial plexus lesions. Among them, patients diagnosed with HNPP were determined and clinical and electrophysiological findings were compared between HNPP and non-HNPP patients with a brachial plexus lesion. Thirteen patients (6.8%) were diagnosed with HNPP among 189 patients with a brachial plexus lesion. Push-ups, as either a punishment or an exercise, was the most frequent preceding event in HNPP patients (76.9%), whereas it was rare in non-HNPP patients. The distal motor latency of the median nerve showed the highest sensitivity (90.9%) and specificity (100%) for HNPP in patients with a brachial plexus lesion. In conclusion, HNPP should be suspected in patients with brachial plexopathy if brachial plexopathy develops after push-ups or if the distal motor latency of median nerves is prolonged.

  16. A report of hereditary neuropathy with liability to pressure palsy (HNPP) presenting with brachial plexopathy: the value of complete electrodiagnostic testing.

    PubMed

    Bulusu, Srinivas; McMillan, Hugh J

    2011-09-01

    Patients with hereditary neuropathy with liability to pressure palsy (HNPP) typically present with a mononeuropathy (particularly peroneal or ulnar palsy) or a brachial plexopathy. Careful electrodiagnostic testing has an important role in establishing the diagnosis of HNPP differentiating this condition from other inherited or acquired neuropathies as well as obviating the need for unnecessary surgeries. We present a case of a patient who presented with a painless brachial plexopathy who was found to have multiple sites of segmental demyelination on nerve conduction studies, consistent with HNPP. We review the clinical and electrodiagnostic features of HNPP including the key electrodiagnostic findings to screen for this disorder.

  17. Facial nerve paralysis and partial brachial plexopathy after epidural blood patch: a case report and review of the literature

    PubMed Central

    Shahien, Radi; Bowirrat, Abdalla

    2011-01-01

    We report a complication related to epidural analgesia for delivery in a 24- year-old woman who was admitted with mild pre-eclampsia and for induction of labor. At the first postpartum day she developed a postdural puncture headache, which was unresponsive to conservative measures. On the fifth day an epidural blood patch was done, and her headache subsided. Sixteen hours later she developed paralysis of the right facial nerve, which was treated with prednisone. Seven days later she complained of pain in the left arm and the posterior region of the shoulder. She was later admitted and diagnosed with partial brachial plexopathy. PMID:21386953

  18. A case of relapsing-remitting facial palsy and ipsilateral brachial plexopathy caused by HSV-1.

    PubMed

    Alstadhaug, Karl B; Kvarenes, Hanne W; Prytz, Jan; Vedeler, Christian

    2016-05-01

    The etiologies of Bell's palsy and brachial neuritis remain uncertain, and the conditions rarely co-occur or reoccur. Here we present a woman in her twenties who had several relapsing-remitting episodes with left-sided facial palsy and brachial neuropathy. The episodes always started with painful left-sided oral blisters. Repeat PCRs HSV-1 DNA from oral vesicular lesions were positive. Extensive screening did not reveal any other underlying cause. Findings on MRI T2-weighted brachial plexus STIR images, using a 3.0-Tesla scanner during an episode, were compatible with brachial plexus neuritis. Except a mannose-binding lectin deficiency, a congenital complement deficiency that is frequently found in the general Caucasian population, no other immunodeficiency was demonstrated in our patient. In vitro resistance to acyclovir was tested negative, but despite prophylactic treatment with the drug in high doses, relapses recurred. To our knowledge, this is the first ever reported documentation of relapsing-remitting facial and brachial plexus neuritis caused by HSV-1.

  19. Heralding Extramedullary Blast Crisis: Horner's Syndrome with Brachial Plexopathy in a Patient with Chronic Myelogenous Leukemia

    PubMed Central

    Patil, Sadanand I.

    2016-01-01

    Chronic myelogenous leukemia (CML) blast crisis is an ominous clinical event that is challenging to treat. This can develop at extramedullary sites rarely and is defined as the infiltration of blasts outside the bone marrow irrespective of proliferation of blasts within the bone marrow. We aim to report an unusual clinical presentation characterized by Horner's syndrome, ipsilateral arm weakness, and cervical lymphadenopathy as the first signs of extramedullary blast crisis in a CML patient. To the best of our knowledge, the extramedullary locations involving the brachial plexus along with cervicothoracic paraspinal chloroma have not been previously reported in the literature. PMID:28096817

  20. Vascularized Thoracodorsal to Suprascapular Nerve Transfer, a Novel Technique to Restore Shoulder Function in Partial Brachial Plexopathy

    PubMed Central

    Potter, Shirley M.; Ferris, Scott I.

    2016-01-01

    We describe the clinical outcome of a novel nerve transfer to restore active shoulder motion in upper brachial plexus injury. The thoracodorsal nerve (TDN) was successfully used as a vascularized donor nerve to neurotize to the suprascapular nerve (SSN) in a patient with limited donor nerve availability. At 4 years follow-up, he had regained useful external rotation of the injured limb, with no significant donor site morbidity. Shoulder abduction return was less impressive, however, and reasons for this are discussed. We provide a comprehensive review of the literature on this topic and a subsequent discussion on the details of this novel technique. This is the first reported case of TDN to SSN transfer, and also the first reported case of a vascularized TDN transfer in the English language literature. We advocate direct thoracodorsal to SSN transfer as a valid surgical option for the restoration of shoulder function in patients with partial brachial plexus avulsion, when conventional nerve donors are unavailable. PMID:27014699

  1. Development of a Standardized Method for Contouring the Lumbosacral Plexus: A Preliminary Dosimetric Analysis of this Organ at Risk Among 15 Patients Treated With Intensity-Modulated Radiotherapy for Lower Gastrointestinal Cancers and the Incidence of Radiation-Induced Lumbosacral Plexopathy

    SciTech Connect

    Yi, Sun K.; Mak, Walter; Yang, Claus C.; Liu Tianxiao; Cui Jing; Chen, Allen M.; Purdy, James A.; Monjazeb, Arta M.; Do, Ly

    2012-10-01

    Purpose: To generate a reproducible step-wise guideline for the delineation of the lumbosacral plexus (LSP) on axial computed tomography (CT) planning images and to provide a preliminary dosimetric analysis on 15 representative patients with rectal or anal cancers treated with an intensity-modulated radiotherapy (IMRT) technique. Methods and Materials: A standardized method for contouring the LSP on axial CT images was devised. The LSP was referenced to identifiable anatomic structures from the L4-5 interspace to the level of the sciatic nerve. It was then contoured retrospectively on 15 patients treated with IMRT for rectal or anal cancer. No dose limitations were placed on this organ at risk during initial treatment planning. Dosimetric parameters were evaluated. The incidence of radiation-induced lumbosacral plexopathy (RILSP) was calculated. Results: Total prescribed dose to 95% of the planned target volume ranged from 50.4 to 59.4 Gy (median 54 Gy). The mean ({+-}standard deviation [SD]) LSP volume for the 15 patients was 100 {+-} 22 cm{sup 3} (range, 71-138 cm{sup 3}). The mean maximal dose to the LSP was 52.6 {+-} 3.9 Gy (range, 44.5-58.6 Gy). The mean irradiated volumes of the LSP were V40Gy = 58% {+-} 19%, V50Gy = 22% {+-} 23%, and V55Gy = 0.5% {+-} 0.9%. One patient (7%) was found to have developed RILSP at 13 months after treatment. Conclusions: The true incidence of RILSP in the literature is likely underreported and is not a toxicity commonly assessed by radiation oncologists. In our analysis the LSP commonly received doses approaching the prescribed target dose, and 1 patient developed RILSP. Identification of the LSP during IMRT planning may reduce RILSP. We have provided a reproducible method for delineation of the LSP on CT images and a preliminary dosimetric analysis for potential future dose constraints.

  2. Brachial plexus lesions in patients with cancer: 100 cases

    SciTech Connect

    Kori, S.H.; Foley, K.M.; Posner, J.B.

    1981-01-01

    In patients with cancer, brachial plexus signs are usually caused by tumor infiltration or injury from radiation therapy (RT). We analyzed 100 cases of brachial plexopathy to determine which clinical criteria helped differentiate tumor from radiation injury. Seventy-eight patients had tumor and 22 had radiation injury. Severe pain occurred in 80% of tumor patients but in only 19% of patients with radiation injury. The lower trunk was involved in 72% of the tumors. Seventy-eight percent of the radiation injuries affected the upper plexus (C5-6). Horner syndrome was more common in tumor, and lymphedema in radiation injury. The time from RT to onset of plexus symptoms, and the dose of RT, also differed.

  3. Radiation-induced gliomas

    PubMed Central

    Prasad, Gautam; Haas-Kogan, Daphne A.

    2013-01-01

    Radiation-induced gliomas represent a relatively rare but well-characterized entity in the neuro-oncologic literature. Extensive retrospective cohort data in pediatric populations after therapeutic intracranial radiation show a clearly increased risk in glioma incidence that is both patient age- and radiation dose/volume-dependent. Data in adults are more limited but show heightened risk in certain groups exposed to radiation. In both populations, there is no evidence linking increased risk associated with routine exposure to diagnostic radiation. At the molecular level, recent studies have found distinct genetic differences between radiation-induced gliomas and their spontaneously-occurring counterparts. Clinically, there is understandable reluctance on the part of clinicians to re-treat patients due to concern for cumulative neurotoxicity. However, available data suggest that aggressive intervention can lead to improved outcomes in patients with radiation-induced gliomas. PMID:19831840

  4. Brachial neuritis.

    PubMed

    Dillin, L; Hoaglund, F T; Scheck, M

    1985-07-01

    Brachial neuritis is an unusual syndrome of unknown etiology that can be confused with other causes of pain or weakness, or both, of the shoulder and arm. It is important to distinguish this disorder because of its dramatic symptoms and relatively good prognosis. Sharp pain, usually in the elbow or shoulder, marks the onset of brachial neuritis, but is relatively short-lived. Weakness generally occurs as the pain is subsiding and most frequently involves the deltoid, spinati, serratus anterior, biceps, and triceps. Paresthesias, atrophy, and sensory loss are inconstant features. Electromyographic findings of fibrillation potentials and positive waves characteristically are found in a pattern indicating combined nerve-root and peripheral nerve involvement. Electromyography more frequently than clinical examination shows that the lesion is bilateral, and also is of both diagnostic and prognostic value. Other laboratory studies serve only to exclude other causes of shoulder pain. The clinical course is variable, but in 90 per cent of patients complete recovery occurs within three years. Recurrences are uncommon.

  5. Brachial Plexus Injuries

    MedlinePlus

    ... to the shoulder, arm, and hand. Brachial plexus injuries are caused by damage to those nerves. Symptoms ... sensation in the arm or hand Brachial plexus injuries can occur as a result of shoulder trauma, ...

  6. Differential diagnosis between radiation and tumor plexopathy of the pelvis

    SciTech Connect

    Thomas, J.E.; Cascino, T.L.; Earle, J.D.

    1985-01-01

    Twenty patients were studied with lumbosacral radiculoplexopathy from radiation treatment and 30 patients with plexus damage from pelvic malignancy. Indolent leg weakness occurred early in radiation disease, whereas pain marked the onset of tumor plexopathy. Eventually, all radiation cases had weakness, which was bilateral in most of them and painless in one-half of them. Tumor patients typically had unilateral weakness, which was painful in all of them. Radiation disease often resulted in serious neurologic disability. Of the tumor patients, 86% were dead within 3 1/2 years after onset of neurologic symptoms.

  7. Radiation-Induced Bioradicals

    NASA Astrophysics Data System (ADS)

    Lahorte, Philippe; Mondelaers, Wim

    This chapter represents the second part of a review in which the production and application of radiation-induced radicals in biological matter are discussed. In part one the general aspects of the four stages (physical, physicochemical, chemical and biological) of interaction of radiation with matter in general and biological matter in particular, were discussed. Here an overview is presented of modem technologies and theoretical methods available for studying these radiation effects. The relevance is highlighted of electron paramagnetic resonance spectroscopy and quantum chemical calculations with respect to obtaining structural information on bioradicals, and a survey is given of the research studies in this field. We also discuss some basic aspects of modem accelerator technologies which can be used for creating radicals and we conclude with an overview of applications of radiation processing in biology and related fields such as biomedical and environmental engineering, food technology, medicine and pharmacy.

  8. Radiation Induced Oral Mucositis

    PubMed Central

    PS, Satheesh Kumar; Balan, Anita; Sankar, Arun; Bose, Tinky

    2009-01-01

    Patients receiving radiotherapy or chemotherapy will receive some degree of oral mucositis The incidence of oral mucositis was especially high in patients: (i) With primary tumors in the oral cavity, oropharynx, or nasopharynx; (ii) who also received concomitant chemotherapy; (iii) who received a total dose over 5,000 cGy; and (iv) who were treated with altered fractionation radiation schedules. Radiation-induced oral mucositis affects the quality of life of the patients and the family concerned. The present day management of oral mucositis is mostly palliative and or supportive care. The newer guidelines are suggesting Palifermin, which is the first active mucositis drug as well as Amifostine, for radiation protection and cryotherapy. The current management should focus more on palliative measures, such as pain management, nutritional support, and maintenance, of good oral hygiene PMID:20668585

  9. Radiation-induced malignant and atypical peripheral nerve sheath tumors

    SciTech Connect

    Foley, K.M.; Woodruff, J.M.; Ellis, F.T.; Posner, J.B.

    1980-04-01

    The reported peripheral nerve complications of therapeutic irradiation in humans include brachial and lumbar plexus fibrosis and cranial and peripheral nerve atrophy. We have encountered 9 patients with malignant (7) and atypical (2) peripheral nerve tumors occurring in an irradiated site suggesting that such tumors represent another delayed effect of radiation treatment on peripheral nerve. In all instances the radio-theray was within an acceptable radiation dosage, yet 3 patients developed local radiation-induced skin and bony abnormalities. The malignant peripheral nerve sheath tumors developed only in the radiation port. Animal studies support the clinical observation that malignant peripheral nerve sheath tumors can occur as a delayed effect of irradiation.

  10. Radiation Induced Genomic Instability

    SciTech Connect

    Morgan, William F.

    2011-03-01

    Radiation induced genomic instability can be observed in the progeny of irradiated cells multiple generations after irradiation of parental cells. The phenotype is well established both in vivo (Morgan 2003) and in vitro (Morgan 2003), and may be critical in radiation carcinogenesis (Little 2000, Huang et al. 2003). Instability can be induced by both the deposition of energy in irradiated cells as well as by signals transmitted by irradiated (targeted) cells to non-irradiated (non-targeted) cells (Kadhim et al. 1992, Lorimore et al. 1998). Thus both targeted and non-targeted cells can pass on the legacy of radiation to their progeny. However the radiation induced events and cellular processes that respond to both targeted and non-targeted radiation effects that lead to the unstable phenotype remain elusive. The cell system we have used to study radiation induced genomic instability utilizes human hamster GM10115 cells. These cells have a single copy of human chromosome 4 in a background of hamster chromosomes. Instability is evaluated in the clonal progeny of irradiated cells and a clone is considered unstable if it contains three or more metaphase sub-populations involving unique rearrangements of the human chromosome (Marder and Morgan 1993). Many of these unstable clones have been maintained in culture for many years and have been extensively characterized. As initially described by Clutton et al., (Clutton et al. 1996) many of our unstable clones exhibit persistently elevated levels of reactive oxygen species (Limoli et al. 2003), which appear to be due dysfunctional mitochondria (Kim et al. 2006, Kim et al. 2006). Interestingly, but perhaps not surprisingly, our unstable clones do not demonstrate a “mutator phenotype” (Limoli et al. 1997), but they do continue to rearrange their genomes for many years. The limiting factor with this system is the target – the human chromosome. While some clones demonstrate amplification of this chromosome and thus lend

  11. Compromising abnormalities of the brachial plexus as displayed by magnetic resonance imaging.

    PubMed

    Collins, J D; Shaver, M L; Disher, A C; Miller, T Q

    1995-01-01

    Magnetic resonance images (MRI) of brachial plexus anatomy bilaterally, not possible by plain radiographs or CT, were presented to the Vascular Surgery, Neurology, and the Neurosurgery departments. Patients were requested for MRI of their brachial plexus. They were referred for imaging and the imaging results were presented to the faculty and housestaff. Our technique was accepted and adopted to begin referrals for MRI evaluation of brachial plexopathy. Over 175 patients have been studied. Eighty-five patients were imaged with the 1.5 Tesla magnet (Signa; General Electric Medical Systems, Milwaukee, WI) 3-D reconstruction MRI. Coronal, transverse (axial), oblique transverse, and sagittal plane T1-weighted and selected T2-weighted pulse sequences were obtained at 4-5 mm slice thickness, 40-45 full field of view, and a 512 x 256 size matrix. Saline water bags were used to enhance the signal between the neck and the thorax. Sites of brachial plexus compromise were demonstrated. Our technique with 3-D reconstruction increased the definition of brachial plexus pathology. The increased anatomical definition enabled the vascular surgeons and neurosurgeons to improve patient care. Brachial plexus in vivo anatomy as displayed by MRI, magnetic resonance angiography (MRA), and 3-D reconstruction offered an opportunity to augment the teaching of clinical anatomy to medical students and health professionals. Selected case presentations (bodybuilder, anomalous muscle, fractured clavicle, thyroid goiter, silicone breast implant rupture, and cervical rib) demonstrated compromise of the brachial plexus displayed by MRI. The MRI and 3-D reconstruction techniques, demonstrating the bilateral landmark anatomy, increased the definition of the clinical anatomy and resulted in greater knowledge of patient care management.

  12. Recurrent brachial plexus neuropathy.

    PubMed

    Bradley, W G; Madrid, R; Thrush, D C; Campbell, M J

    1975-09-01

    The clinical, electrophysiological and pathological changes in 3 patients with recurrent attacks of non-traumatic brachial plexus neuropathy have been described. Two had recurrent attacks and a dominant family history of similar attacks, together with evidence of lesser degrees of nerve involvement outside the brachial plexus. In one patient the attacks were moderately painful, while in the other there was little or no pain. Only one showed undue slowing of motor nerve conduction during ischaemia, but in both cases the sural nerves had the changes of tomaculous neuropathy, with many sausage-shaped swellings of the myelin sheaths, and extensive segmental demyelination and remyelination. The third patient had two attacks of acute brachial plexus neuropathy which were both extremely painful. The clinical features were compatible with a diagnosis of neuralgic amuotrophy. In the second attack, there was vagus nerve involvement and the sural nerve showed evidence of healed extensive segmental demyelination. The various syndromes presenting with acute non-traumatic brachial plexus neuropathy are reviewed, and a tentative nonsological classification advanced. Most patients fall into the category of acute, painful paralysis with amyotrophy, with no family history and no evidence of lesions outside the brachial plexus. It is suggested that the term "neuralgic amyotrophy" be restricted to this group. Patients with features outside this clinical picture probably suffer from other disease entities presenting with brachial plexus neuropathy. The familial cases constitute one or more aetioliogical subgroups, differing from neuralgic amyotrophy in the frequency of recurrences, the relative freedom from pain in the attacks, the frequency of nerve lesions outside the brachial plexus, and of hypotelorism. Individual attacks of acute brachial plexus neuropathy, however, may be identical in patients with the different diseases, and further pathological and biochemical studies are

  13. Pelvic radiculopathies, lumbosacral plexopathies, and neuropathies in oncologic disease: a multidisciplinary approach to a diagnostic challenge

    PubMed Central

    Berry, Jonathan; Nisbet, Angus; Bloomfield, David; Burkill, Guy

    2013-01-01

    Abstract The purpose of this article is to familiarize the reader with the anatomy of the major pelvic nerves and the clinical features of associated lumbosacral plexopathies. To demonstrate this we illustrate several cases of malignant lumbosacral plexopathy on computed tomography, magnetic resonance imaging, and positron emission tomography/computed tomography. A new lumbosacral plexopathy in a patient with a prior history of abdominal or pelvic malignancy is usually of malignant etiology. Biopsies may be required to definitively differentiate tumour from posttreatment fibrosis, and in cases of inconclusive sampling or where biopsies are not possible, follow-up imaging may be necessary. In view of the complexity of clinical findings often confounded by a history of prior surgery and/or radiotherapy, a multidisciplinary approach between oncologists, neurologists, and radiologists is often required for what can be a diagnostic challenge. PMID:24433993

  14. Radiation-induced genomic instability

    NASA Technical Reports Server (NTRS)

    Kronenberg, A.

    1994-01-01

    Quantitative assessment of the heritable somatic effects of ionizing radiation exposures has relied upon the assumption that radiation-induced lesions were 'fixed' in the DNA prior to the first postirradiation mitosis. Lesion conversion was thought to occur during the initial round of DNA replication or as a consequence of error-prone enzymatic processing of lesions. The standard experimental protocols for the assessment of a variety of radiation-induced endpoints (cell death, specific locus mutations, neoplastic transformation and chromosome aberrations) evaluate these various endpoints at a single snapshot in time. In contrast with the aforementioned approaches, some studies have specifically assessed radiation effects as a function of time following exposure. Evidence has accumulated in support of the hypothesis that radiation exposure induces a persistent destabilization of the genome. This instability has been observed as a delayed expression of lethal mutations, as an enhanced rate of accumulation of non-lethal heritable alterations, and as a progressive intraclonal chromosomal heterogeneity. The genetic controls and biochemical mechanisms underlying radiation-induced genomic instability have not yet been delineated. The aim is to integrate the accumulated evidence that suggests that radiation exposure has a persistent effect on the stability of the mammalian genome.

  15. Obstetrical brachial plexus palsy.

    PubMed

    Romaña, M C; Rogier, A

    2013-01-01

    Obstetrical brachial plexus palsy is considered to be the result of a trauma during the delivery, even if there remains some controversy surrounding the causes. Although most babies recover spontaneously in the first 3 months of life, a small number remains with poor recovery which requires surgical brachial plexus exploration. Surgical indications depend on the type of lesion (producing total or partial palsy) and particularly the nonrecovery of biceps function by the age of 3 months. In a global palsy, microsurgery will be mandatory and the strategy for restoration will focus first on hand reinnervation and secondarily on providing elbow flexion and shoulder stability. Further procedures may be necessary during growth in order to avoid fixed contractured deformities or to give or increase strength of important muscle functions like elbow flexion or wrist extension. The author reviews the history of obstetrical brachial plexus injury, epidemiology, and the specifics of descriptive and functional anatomy in babies and children. Clinical manifestations at birth are directly correlated with the anatomical lesion. Finally, operative procedures are considered, including strategies of reconstruction with nerve grafting in infants and secondary surgery to increase functional capacity at later ages. However, normal function is usually not recovered, particularly in total brachial plexus palsy.

  16. Radiation-induced cardiovascular effects

    NASA Astrophysics Data System (ADS)

    Tapio, Soile

    Recent epidemiological studies indicate that exposure to ionising radiation enhances the risk of cardiovascular mortality and morbidity in a moderate but significant manner. Our goal is to identify molecular mechanisms involved in the pathogenesis of radiation-induced cardiovascular disease using cellular and mouse models. Two radiation targets are studied in detail: the vascular endothelium that plays a pivotal role in the regulation of cardiac function, and the myocardium, in particular damage to the cardiac mitochondria. Ionising radiation causes immediate and persistent alterations in several biological pathways in the endothelium in a dose- and dose-rate dependent manner. High acute and cumulative doses result in rapid, non-transient remodelling of the endothelial cytoskeleton, as well as increased lipid peroxidation and protein oxidation of the heart tissue, independent of whether exposure is local or total body. Proteomic and functional changes are observed in lipid metabolism, glycolysis, mitochondrial function (respiration, ROS production etc.), oxidative stress, cellular adhesion, and cellular structure. The transcriptional regulators Akt and PPAR alpha seem to play a central role in the radiation-response of the endothelium and myocardium, respectively. We have recently started co-operation with GSI in Darmstadt to study the effect of heavy ions on the endothelium. Our research will facilitate the identification of biomarkers associated with adverse cardiac effects of ionising radiation and may lead to the development of countermeasures against radiation-induced cardiac damage.

  17. Traumatic Brachial Artery Injuries

    PubMed Central

    Ergunes, Kazim; Yilik, Levent; Ozsoyler, Ibrahim; Kestelli, Mert; Ozbek, Cengiz; Gurbuz, Ali

    2006-01-01

    We performed this retrospective study to analyze our strategies for managing and surgically treating brachial artery injuries. Fifty-seven patients with a total of 58 traumatic brachial artery injuries underwent surgery at our institution, from August 1996 through November 2004. Fifty-four patients were male and 3 were female (age range, 7 to 75 years; mean, 29.4 years). Forty-four of the patients had penetrating injuries (18 had stab wounds; 16, window glass injuries; and 10, industrial accidents), 10 had blunt trauma injuries (traffic accidents), and 3 had gunshot injuries. Fourteen patients (24.6%) had peripheral nerve injury. All patients underwent Doppler ultrasonographic examination. The repair of the 58 arterial injuries involved end-to-end anastomosis for 32 injuries (55.2%), reverse saphenous vein graft interpositional grafts for 18 (31%), and primary repair for 8 (13.8%). Venous continuity was achieved in 11 (84.6%) of 13 patients who had major venous injuries. Nine of the 57 patients (15.8%) required primary fasciotomy. Follow-up showed that 5 of the 14 patients with peripheral nerve injury had apparent disabilities due to nerve injury. One patient underwent amputation. There were no deaths. We believe that good results can be achieved in patients with brachial artery injuries by use of careful physical examination, Doppler ultrasonography, and restoration of viability with vascular repair and dbridement of nonviable tissues. Traumatic neurologic injury frequently leads to disability of the extremities. PMID:16572866

  18. Radiation-Induced Vaccination to Breast Cancer

    DTIC Science & Technology

    2014-10-01

    Award Number: W81XWH-11-1-0531 TITLE: Radiation-Induced Vaccination to Breast Cancer PRINCIPAL INVESTIGATOR: William H. McBride CONTRACTING...TITLE AND SUBTITLE Radiation-Induced Vaccination to Breast Cancer 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-11-1-0531 5c. PROGRAM ELEMENT NUMBER

  19. Treatment of Radiation-Induced Urethral Strictures.

    PubMed

    Hofer, Matthias D; Liu, Joceline S; Morey, Allen F

    2017-02-01

    Radiation therapy may result in urethral strictures from vascular damage. Most radiation-induced urethral strictures occur in the bulbomembranous junction, and urinary incontinence may result as a consequence of treatment. Radiation therapy may compromise reconstruction due to poor tissue healing and radionecrosis. Excision and primary anastomosis is the preferred urethroplasty technique for radiation-induced urethral stricture. Principles of posterior urethroplasty for trauma may be applied to the treatment of radiation-induced urethral strictures. Chronic management with suprapubic tube is an option based on patient comorbidities and preference.

  20. Radiation-induced moyamoya syndrome

    SciTech Connect

    Desai, Snehal S.; Paulino, Arnold C. . E-mail: apaulino@tmh.tmc.edu; Mai, Wei Y.; Teh, Bin S.

    2006-07-15

    Purpose: The moyamoya syndrome is an uncommon late complication after radiotherapy (RT). Methods and Materials: A PubMed search of English-language articles, with radiation, radiotherapy, and moyamoya syndrome used as search key words, yielded 33 articles from 1967 to 2002. Results: The series included 54 patients with a median age at initial RT of 3.8 years (range, 0.4 to 47). Age at RT was less than 5 years in 56.3%, 5 to 10 years in 22.9%, 11 to 20 years in 8.3%, 21 to 30 years in 6.3%, 31 to 40 years in 2.1%, and 41 to 50 years in 4.2%. Fourteen of 54 patients (25.9%) were diagnosed with neurofibromatosis type 1 (NF-1). The most common tumor treated with RT was low-grade glioma in 37 tumors (68.5%) of which 29 were optic-pathway glioma. The average RT dose was 46.5 Gy (range, 22-120 Gy). For NF-1-positive patients, the average RT dose was 46.5 Gy, and for NF-1-negative patients, it was 58.1 Gy. The median latent period for development of moyamoya syndrome was 40 months after RT (range, 4-240). Radiation-induced moyamoya syndrome occurred in 27.7% of patients by 2 years, 53.2% of patients by 4 years, 74.5% of patients by 6 years, and 95.7% of patients by 12 years after RT. Conclusions: Patients who received RT to the parasellar region at a young age (<5 years) are the most susceptible to moyamoya syndrome. The incidence for moyamoya syndrome continues to increase with time, with half of cases occurring within 4 years of RT and 95% of cases occurring within 12 years. Patients with NF-1 have a lower radiation-dose threshold for development of moyamoya syndrome.

  1. [Ankle brachial index measurement].

    PubMed

    Rucigaj, Tanja Planinsek

    2014-10-01

    Ultrasound examinations are noninvasive diagnostic methods which, along with appropriate history and clinical examination, provide basic information on the etiology and spread of the disease, as well as on treatment options required in patients with chronic venous insufficiency and arterial flow impairment. Doppler flow meter offers useful data on venous blood return, primarily in great veins, while both deep and superficial veins as well as arteries can be visualized and data on venous and arterial hemodynamics obtained by duplex ultrasonography. In addition, Doppler flow meter provides data on the peripheral arterial system action through ankle brachial index measurement, which will guide the choice of compression therapy when deciding on the treatment of peripheral arterial disease and mixed arteriovenous leg ulcers. However, diagnosis of arterial insufficiency requires additional examinations.

  2. Radiation-induced accelerated coronary arteriosclerosis

    SciTech Connect

    Mittal, B.; Deutsch, M.; Thompson, M.; Dameshek, H.L.

    1986-07-01

    There is a paucity of information on radiation-induced coronary heart disease. A young patient with myocardial infarction following mediastinal irradiation is described. The role of radiotherapy and chemotherapy on the subsequent development of coronary heart disease is discussed.

  3. Brachial plexus injury in newborns

    MedlinePlus

    Gentle massage of the arm and range-of-motion exercises are recommended for mild cases. The infant ... the American College of Obstetricians and Gynecologists' Task Force on Neonatal Brachial Plexus Palsy. Obstet Gynecol . 2014 ...

  4. Radiation-Induced Vaccination to Breast Cancer

    DTIC Science & Technology

    2015-10-01

    Award Number: W81XWH-11-1-0531 TITLE: Radiation-Induced Vaccination to Breast Cancer PRINCIPAL INVESTIGATOR: William H. McBride CONTRACTING...FORM TO THE ABOVE ADDRESS. 1. REPORT DATE 2. REPORT TYPE Annual 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Radiation-Induced Vaccination to...determine abscopal responses that are hypothesized to be due to RT- induced vaccination . RT was started 10 days after the first and 3rd dose of

  5. Radiation-induced sarcoma of the thyroid

    SciTech Connect

    Griem, K.L.; Robb, P.K.; Caldarelli, D.D.; Templeton, A.C. )

    1989-08-01

    A 23-year-old white man presented with a thyroid mass 12 years after receiving high-dose radiotherapy for a T2 and N1 lymphoepithelioma of the nasopharynx. Following subtotal thyroidectomy, a histopathologic examination revealed liposarcoma of the thyroid gland. The relationship between sarcomas and irradiation is described and Cahan and colleagues' criteria for radiation-induced sarcomas are reviewed. To our knowledge, we are presenting the first such case of a radiation-induced sarcoma of the thyroid gland.

  6. Factors that modify radiation-induced carcinogenesis.

    PubMed

    Kennedy, Ann R

    2009-11-01

    It is known that numerous factors can influence radiation carcinogenesis in animals; these factors include the specific characteristics of the radiation (radiation type and dose, dose-rate, dose-fractionation, dose distribution, etc.) as well as many other contributing elements that are not specific to the radiation exposure, such as animal genetic characteristics and age, the environment of the animal, dietary factors and whether specific modifying agents for radiation carcinogenesis have been utilized in the studies. This overview focuses on the modifying factors for radiation carcinogenesis, in both in vivo and in vitro systems, and includes a discussion of agents that enhance (e.g., promoting agents) or suppress (e.g., cancer preventive agents) radiation-induced carcinogenesis. The agents that enhance or suppress radiation carcinogenesis in experimental model systems have been shown to lead to effects equally as large as other known modifying factors for radiation-induced carcinogenesis (e.g., dose-rate, dose-fractionation, linear energy transfer). It is known that dietary factors play an important role in determining the yields of radiation-induced cancers in animal model systems, and it is likely that they also influence radiation-induced cancer risks in human populations.

  7. [Quantification of radiation-induced genetic risk].

    PubMed

    Ehling, U H

    1987-05-01

    Associated with technical advances of our civilization is a radiation- and chemically-induced increase in the germ cell mutation rate in man. This would result in an increase in the frequency of genetic diseases and would be detrimental to future generations. It is the duty of our generation to keep this risk as low as possible. The estimation of the radiation-induced genetic risk of human populations is based on the extrapolation of results from animal experiments. Radiation-induced mutations are stochastic events. The probability of the event depends on the dose; the degree of the damage does not. The different methods to estimate the radiation-induced genetic risk will be discussed. The accuracy of the predicted results will be evaluated by a comparison with the observed incidence of dominant mutations in offspring born to radiation exposed survivors of the Hiroshima and Nagasaki atomic bombings. These methods will be used to predict the genetic damage from the fallout of the reactor accident at Chernobyl. For the exposure dose we used the upper limits of the mean effective life time equivalent dose from the fallout values in the Munich region. According to the direct method for the risk estimation we will expect for each 100 to 500 spontaneous dominant mutations one radiation-induced mutation in the first generation. With the indirect method we estimate a ratio of 100 dominant spontaneous mutations to one radiation-induced dominant mutation. The possibilities and the limitations of the different methods to estimate the genetic risk will be discussed. The discrepancy between the high safety standards for radiation protection and the low level of knowledge for the toxicological evaluation of chemical mutagens will be emphasized.

  8. [Rhabdomyolysis and lumbosacral plexopathy in intravenous drug addict: report of a case].

    PubMed

    Diaz Guzman, J; Pastor Valverde, C; Gil Grande, R; Alonso Ortiz, A; Trueba Gutierrez, J L

    1996-02-01

    There are several neuromuscular complications in the intravenous heroin addict (IHA). Someone may be due to direct toxic effect of the substance, but other ones may be associated to abuser's typical diseases (i.e. HIV infection). We present a 27 year-old IHA patient, HIV positive, that develop acute rhabdomyolisis with severe neuromuscular involvement, and consistent clinical and electrodiagnostic features of lumbosacral plexus neuropathy, forteen hours after an heroin inyection. Thirty months later, the patient is severely disabled, but her initial painfull and paretic picture have improved. The association of rhabdomyolisis-lumbosacral plexopathy (RLPS) is ocasionally reported. It has been proposed that RLSP is etiologically related to mecanic, toxic and immunologic factors.

  9. Radiation-induced meningiomas in pediatric patients.

    PubMed

    Moss, S D; Rockswold, G L; Chou, S N; Yock, D; Berger, M S

    1988-04-01

    Radiation-induced meningiomas rarely have latency periods short enough from the time of irradiation to the clinical presentation of the tumor to present in the pediatric patient. Three cases of radiation-induced intracranial meningiomas in pediatric patients are presented. The first involved a meningioma of the right frontal region in a 10-year-old boy 6 years after the resection and irradiation of a 4th ventricular medulloblastoma. Review of our pediatric tumor cases produced a second case of a left temporal fossa meningioma presenting in a 15-year-old boy with a history of irradiation for retinoblastoma at age 3 years and a third case of a right frontoparietal meningioma in a 15-year-old girl after irradiation for acute lymphoblastic leukemia. Only three cases of meningiomas presenting in the pediatric age group after radiation therapy to the head were detected in our review of the literature.

  10. Radiation-induced meningiomas in pediatric patients

    SciTech Connect

    Moss, S.D.; Rockswold, G.L.; Chou, S.N.; Yock, D.; Berger, M.S.

    1988-04-01

    Radiation-induced meningiomas rarely have latency periods short enough from the time of irradiation to the clinical presentation of the tumor to present in the pediatric patient. Three cases of radiation-induced intracranial meningiomas in pediatric patients are presented. The first involved a meningioma of the right frontal region in a 10-year-old boy 6 years after the resection and irradiation of a 4th ventricular medulloblastoma. Review of our pediatric tumor cases produced a second case of a left temporal fossa meningioma presenting in a 15-year-old boy with a history of irradiation for retinoblastoma at age 3 years and a third case of a right frontoparietal meningioma in a 15-year-old girl after irradiation for acute lymphoblastic leukemia. Only three cases of meningiomas presenting in the pediatric age group after radiation therapy to the head were detected in our review of the literature.

  11. Study of chemical and radiation induced carcinogenesis

    SciTech Connect

    Chmura, A.

    1995-11-01

    The study of chemical and radiation induced carcinogenesis has up to now based many of its results on the detection of genetic aberrations using the fluorescent in situ hybridization (FISH) technique. FISH is time consuming and this tends to hinder its use for looking at large numbers of samples. We are currently developing new technological advances which will increase the speed, clarity and functionality of the FISH technique. These advances include multi-labeled probes, amplification techniques, and separation techniques.

  12. Radiation-induced heart disease in rats

    SciTech Connect

    Lauk, S.; Kiszel, Z.; Buschmann, J.; Trott, K.R.

    1985-04-01

    After local irradiation of the rat heart with X ray doses of over 10 Gy (single dose), animals developed symptoms of radiation-induced heart disease, which at higher doses would lead to fatal cardiac failure. The LD 50 at 1 year was between 15 Gy and 20 Gy. The pericardium and epicardium responded to irradiation with exudative pericarditis after 4 months. Focal myocardial damage was secondary to progressive capillary damage.

  13. A report on radiation-induced gliomas

    SciTech Connect

    Salvati, M.; Artico, M.; Caruso, R.; Rocchi, G.; Orlando, E.R.; Nucci, F. )

    1991-01-15

    Radiation-induced gliomas are uncommon, with only 73 cases on record to date. The disease that most frequently occasioned radiation therapy has been acute lymphoblastic leukemia (ALL). Three more cases are added here, two after irradiation for ALL and one after irradiation for tinea capitis. In a review of the relevant literature, the authors stress the possibility that the ALL-glioma and the retinoblastoma-glioma links point to syndromes in their own right that may occur without radiation therapy.56 references.

  14. Radiation-induced injury of the esophagus

    SciTech Connect

    Lepke, R.A.; Libshitz, H.I.

    1983-08-01

    Forty patients with functional or morphologic esophageal abnormalities following radiotherapy were identified. Abnormalities included abnormal motility with and without mucosal edema, stricture, ulceration and pseudodiverticulum, and fistula. Abnormal motility occurred 4 to 12 weeks following radiotherapy alone and as early as 1 week after therapy when concomitant chemotherapy had been given. Strictures developed 4 to 8 months following completion of radiotherapy. Ulceration, pseudodiverticulum, and fistula formation did not develop in a uniform time frame. Radiation-induced esophageal injury is more frequent when radiotherapy and chemotherapy are combined than it is with radiotherapy alone.

  15. Radiation-induced esophagitis in lung cancer

    PubMed Central

    Baker, Sarah; Fairchild, Alysa

    2016-01-01

    Radiation-induced esophagitis is the most common local acute toxicity of radiotherapy (RT) delivered for the curative or palliative intent treatment of lung cancer. Although concurrent chemotherapy and higher RT dose are associated with increased esophagitis risk, advancements in RT techniques as well as adherence to esophageal dosimetric constraints may reduce the incidence and severity. Mild acute esophagitis symptoms are generally self-limited, and supportive management options include analgesics, acid suppression, diet modification, treatment for candidiasis, and maintenance of adequate nutrition. Esophageal stricture is the most common late sequela from esophageal irradiation and can be addressed with endoscopic dilatation. Approaches to prevent or mitigate these toxicities are also discussed. PMID:28210168

  16. Radiation induced conductivity in space dielectric materials

    SciTech Connect

    Hanna, R.; Paulmier, T. Belhaj, M.; Dirassen, B.; Molinie, P.; Payan, D.; Balcon, N.

    2014-01-21

    The radiation-induced conductivity of some polymers was described mainly in literature by a competition between ionization, trapping/detrapping, and recombination processes or by radiation assisted ageing mechanisms. Our aim is to revise the effect of the aforementioned mechanisms on the complex evolution of Teflon{sup ®} FEP under space representative ionizing radiation. Through the definition of a new experimental protocol, revealing the effect of radiation dose and relaxation time, we have been able to demonstrate that the trapping/recombination model devised in this study agrees correctly with the observed experimental phenomenology at qualitative level and allows describing very well the evolution of radiation induced conductivity with irradiation time (or received radiation dose). According to this model, the complex behavior observed on Teflon{sup ®} FEP may be basically ascribed to the competition between electron/hole pairs generation and recombination: electrons are deeply trapped and act as recombination centers for free holes. Relaxation effects have been characterized through successive irradiations steps and have been again well described with the defined model at qualitative level: recombination centers created by the irradiation induce long term alteration on the electric properties, especially the effective bulk conductivity. One-month relaxation does not allow a complete recovery of the material initial charging behavior.

  17. Radiation Dose to the Brachial Plexus in Head-and-Neck Intensity-Modulated Radiation Therapy and Its Relationship to Tumor and Nodal Stage

    SciTech Connect

    Truong, Minh Tam; Romesser, Paul B.; Qureshi, Muhammad M.; Kovalchuk, Nataliya; Orlina, Lawrence; Willins, John

    2012-09-01

    Purpose: The purpose of this retrospective study was to determine tumor factors contributing to brachial plexus (BP) dose in head-and-neck cancer (HNC) patients treated with intensity-modulated radiotherapy (IMRT) when the BP is routinely contoured as an organ at risk (OAR) for IMRT optimization. Methods and Materials: From 2004 to 2011, a total of 114 HNC patients underwent IMRT to a total dose of 69.96 Gy in 33 fractions, with the right and left BP prospectively contoured as separate OARs in 111 patients and the ipsilateral BP contoured in 3 patients (total, 225 BP). Staging category T4 and N2/3 disease were present in 34 (29.8%) and 74 (64.9%) patients, respectively. During IMRT optimization, the intent was to keep the maximum BP dose to {<=}60 Gy, but prioritizing tumor coverage over achieving the BP constraints. BP dose parameters were compared with tumor and nodal stage. Results: With a median follow-up of 16.2 months, 43 (37.7%) patients had {>=}24 months of follow-up with no brachial plexopathy reported. Mean BP volume was 8.2 {+-} 4.5 cm{sup 3}. Mean BP maximum dose was 58.1 {+-} 12.2 Gy, and BP mean dose was 42.2 {+-} 11.3 Gy. The BP maximum dose was {<=}60, {<=}66, and {<=}70 Gy in 122 (54.2%), 185 (82.2%), and 203 (90.2%) BP, respectively. For oropharynx, hypopharynx, and larynx sites, the mean BP maximum dose was 58.4 Gy and 63.4 Gy in T0-3 and T4 disease, respectively (p = 0.002). Mean BP maximum dose with N0/1 and N2/3 disease was 52.8 Gy and 60.9 Gy, respectively (p < 0.0001). Conclusions: In head-and-neck IMRT, dose constraints for the BP are difficult to achieve to {<=}60 to 66 Gy with T4 disease of the larynx, hypopharynx, and oropharynx or N2/3 disease. The risk of brachial plexopathy is likely very small in HNC patients undergoing IMRT, although longer follow-up is required.

  18. Role of neurotensin in radiation-induced hypothermia in rats

    SciTech Connect

    Kandasamy, S.B.; Hunt, W.A.; Harris, A.H. )

    1991-05-01

    The role of neurotensin in radiation-induced hypothermia was examined. Intracerebroventricular (ICV) administration of neurotensin produced dose-dependent hypothermia. Histamine appears to mediate neurotensin-induced hypothermia because the mast cell stabilizer disodium cromoglycate and antihistamines blocked the hypothermic effects of neurotensin. An ICV pretreatment with neurotensin antibody attenuated neurotensin-induced hypothermia, but did not attenuate radiation-induced hypothermia, suggesting that radiation-induced hypothermia was not mediated by neurotensin.

  19. Radiation induced carcinoma of the larynx

    SciTech Connect

    Amendola, B.E.; Amendola, M.A.; McClatchey, K.D.

    1985-07-01

    A squamous cell carcinoma presented in a 20 year old female nonsmoker three years after receiving a high dosage of radiation therapy to the base of the skull, face and entire neuroaxis and intense combination chemotherapy for a parameningeal rhabdomyosarcoma of the paranasal sinuses is reported. The larynx received a dose of about 3,500 rads over an eight week period. This dosage in conjunction with the associated intense chemotherapy regimen given to the patient may explain the appearance of a radiation induced tumor in an unusually short latent period. This certainly represents a risk in young patients in whom an aggressive combined approach is taken and the physician should be aware of.

  20. Radiation-induced spinal cord hemorrhage (hematomyelia).

    PubMed

    Agarwal, Amit; Kanekar, Sangam; Thamburaj, Krishnamurthy; Vijay, Kanupriya

    2014-10-23

    Intraspinal hemorrhage is very rare and intramedullary hemorrhage, also called hematomyelia, is the rarest form of intraspinal hemorrhage, usually related to trauma. Spinal vascular malformations such intradural arteriovenous malformations are the most common cause of atraumatic hematomyelia. Other considerations include warfarin or heparin anticoagulation, bleeding disorders, spinal cord tumors. Radiation-induced hematomyelia of the cord is exceedingly rare with only one case in literature to date. We report the case of an 8 year old girl with Ewing's sarcoma of the thoracic vertebra, under radiation therapy, presenting with hematomyelia. We describe the clinical course, the findings on imaging studies and the available information in the literature. Recognition of the clinical pattern of spinal cord injury should lead clinicians to perform imaging studies to evaluate for compressive etiologies.

  1. Transesophageal Echocardiography and Radiation-induced Damages

    PubMed Central

    Cottini, Marzia; Polizzi, Vincenzo; Pino, Paolo Giuseppe; Buffa, Vitaliano; Musumeci, Francesco

    2016-01-01

    The long-term sequelae of mantle therapy include, especially lung and cardiac disease but also involve the vessels and the organs in the neck and thorax (such as thyroid, aorta, and esophagus). We presented the case of 66-year-old female admitted for congestive heart failure in radiation-induced heart disease. The patient had undergone to massive radiotherapy 42 years ago for Hodgkin's disease (type 1A). Transesophageal echocardiography was performed unsuccessfully with difficulty because of the rigidity and impedance of esophageal walls. Our case is an extraordinary report of radiotherapy's latency effect as a result of dramatic changes in the structure of mediastinum, in particular in the esophagus, causing unavailability of a transesophageal echocardiogram. PMID:27867461

  2. Radiation-induced mutations and plant breeding

    SciTech Connect

    Naqvi, S.H.M.

    1985-01-01

    Ionizing radiation could cause genetic changes in an organism and could modify gene linkages. The induction of mutation through radiation is random and the probability of getting the desired genetic change is low but can be increased by manipulating different parameters such as dose rate, physical conditions under which the material has been irradiated, etc. Induced mutations have been used as a supplement to conventional plant breeding, particularly for creating genetic variability for specific characters such as improved plant structure, pest and disease resistance, and desired changes in maturity period; more than 200 varieties of crop plants have been developed by this technique. The Pakistan Atomic Energy Commission has used this technique fruitfully to evolve better germplasm in cotton, rice, chickpea, wheat and mungbean; some of the mutants have become popular commercial varieties. This paper describes some uses of radiation induced mutations and the results achieved in Pakistan so far.

  3. Radiation-induced mutation at minisatellite loci

    SciTech Connect

    Dubrova, Y.E. |; Nesterov, V.N.; Krouchinsky, N.G.

    1997-10-01

    We are studying the radiation-induced increase of mutation rate in minisatellite loci in mice and humans. Minisatellite mutations were scored by multilocus DNA fingerprint analysis in the progeny of {gamma}-irradiated and non-irradiated mice. The frequency of mutation in offspring of irradiated males was 1.7 higher that in the control group. Germline mutation at human minisatellite loci was studied among children born in heavily polluted areas of the Mogilev district of Belarus after the Chernobyl accident and in a control population. The frequency of mutation assayed both by DNA fingerprinting and by eight single locus probes was found to be two times higher in the exposed families than in the control group. Furthermore, mutation rate was correlated with the parental radiation dose for chronic exposure {sup 137}Cs, consistent with radiation-induction of germline mutation. The potential use of minisatellites in monitoring germline mutation in humans will be discussed.

  4. Severe Brachial Plexus Injuries in American Football.

    PubMed

    Daly, Charles A; Payne, S Houston; Seiler, John G

    2016-11-01

    This article reports a series of severe permanent brachial plexus injuries in American football players. The authors describe the mechanisms of injury and outcomes from a more contemporary treatment approach in the form of nerve transfer tailored to the specific injuries sustained. Three cases of nerve transfer for brachial plexus injury in American football players are discussed in detail. Two of these patients regained functional use of the extremity, but 1 patient with a particularly severe injury did not regain significant function. Brachial plexus injuries are found along a spectrum of brachial plexus stretch or contusion that includes the injuries known as "stingers." Early identification of these severe brachial plexus injuries allows for optimal outcomes with timely treatment. Diagnosis of the place of a given injury along this spectrum is difficult and requires a combination of imaging studies, nerve conduction studies, and close monitoring of physical examination findings over time. Although certain patients may be at higher risk for stingers, there is no evidence to suggest that this correlates with a higher risk of severe brachial plexus injury. Unfortunately, no equipment or strengthening program has been shown to provide a protective effect against these severe injuries. Patients with more severe injuries likely have less likelihood of functional recovery. In these patients, nerve transfer for brachial plexus injury offers the best possibility of meaningful recovery without significant morbidity. [ Orthopedics. 2016; 39(6):e1188-e1192.].

  5. Neurinomas of the brachial plexus: case report.

    PubMed

    Forte, A; Gallinaro, L S; Bertagni, A; Montesano, G; Prece, V; Illuminati, G

    1999-01-01

    Neurinomas, also referred to as neurilemmomas and schwannomas, are rare benign tumours of the peripheral nerves, a low proportion of which arise from the brachial plexus. Authors report a case of an ancient schwannoma arising from the brachial plexus. The tumour, usually asymptomatic, may cause sensory radicular symptoms, or rarely motor deficits in the involved arm. Enucleation of the tumour from the nerve without damage to any of the fascicles is the correct treatment.

  6. Radiation-induced degradation of aqueous fluoranthene

    NASA Astrophysics Data System (ADS)

    Popov, Petar; Getoff, Nikola

    2005-01-01

    The radiation-induced degradation of fluoranthene (FA) in slightly alkaline aqueous solution was investigated in the presence of air as well as of N 2O. Depending on the starting FA-concentration the determined Gi(-FA) was 0.34 for 1×10 -5 mol/l FA upto 0.67 for 4.6×10 -5 mol/l FA. As major radiolytic products found by HPLC-analysis were: 9-fluorene carboxylic acid ( Gi =0.006), 9-fluorenone ( Gi=0.004) and fluorene ( Gi=0.002) in addition to a mixture of carboxylic acids and aldehydes. In the presence of N 2O (90% OH, 10% H) practically the same products were observed, however in this case the yield of the carboxylic acids was about 2-times higher than in solutions saturated with air, but 4-times less aldehydes, resp. For illustration of the rather complicated degradation process a probable reaction mechanism is presented.

  7. Radiation-induced segregation, hardening, and IASCC

    SciTech Connect

    Eason, E.D.; Nelson, E.E.

    1995-12-31

    Intergranular cracking has been discovered after extended radiation exposure in several boiling water reactor (BWR) internal components made of austenitic stainless steel and nickel-based alloys. There are fewer field observations of intergranular cracking in pressurized water reactors (PWR), but failures have occurred in bolts, springs, and fuel cladding. There is concern for other PWR components, some of which will receive greater radiation doses than BWR components during the plant lifetime. This paper presents the results of an investigation on the connection between radiation induced segregation, hardening and irradiation-assisted stress corrosion cracking (IASCC). A data base was developed containing the available data on austenitic stainless steel where the grain boundary composition was measured by Field Emission Gun-Scanning Transmission Election Microscopy (FEG-STEM), the stress corrosion susceptibility was measured by constant extension rate tests (CERT) in light water reactor environments, some estimate of irradiated strength was available and the irradiation was conducted in a power reactor. The data base was analyzed using advanced data analysis techniques, including tree-structured pattern recognition and transformation analysis codes. The most sensitive variables and optimal modeling forms were identified using these techniques, then preliminary models were calibrated using nonlinear least squares. The results suggest that more than one mechanism causes IASCC.

  8. Ionizing Radiation-Induced Endothelial Cell Senescence and Cardiovascular Diseases

    PubMed Central

    Wang, Yingying; Boerma, Marjan; Zhou, Daohong

    2016-01-01

    Exposure to ionizing radiation induces not only apoptosis but also senescence. While the role of endothelial cell apoptosis in mediating radiation-induced acute tissue injury has been extensively studied, little is known about the role of endothelial cell senescence in the pathogenesis of radiation-induced late effects. Senescent endothelial cells exhibit decreased production of nitric oxide and expression of thrombomodulin, increased expression of adhesion molecules, elevated production of reactive oxygen species and inflammatory cytokines and an inability to proliferate and form capillary-like structures in vitro. These findings suggest that endothelial cell senescence can lead to endothelial dysfunction by dysregulation of vasodilation and hemostasis, induction of oxidative stress and inflammation and inhibition of angiogenesis, which can potentially contribute to radiation-induced late effects such as cardiovascular diseases (CVDs). In this article, we discuss the mechanisms by which radiation induces endothelial cell senescence, the roles of endothelial cell senescence in radiation-induced CVDs and potential strategies to prevent, mitigate and treat radiation-induced CVDs by targeting senescent endothelial cells. PMID:27387862

  9. Radiation-Induced Alopecia after Endovascular Embolization under Fluoroscopy

    PubMed Central

    Ounsakul, Vipawee; Iamsumang, Wimolsiri

    2016-01-01

    Radiation-induced alopecia after fluoroscopically guided procedures is becoming more common due to an increasing use of endovascular procedures. It is characterized by geometric shapes of nonscarring alopecia related to the area of radiation. We report a case of a 46-year-old man presenting with asymptomatic, sharply demarcated rectangular, nonscarring alopecic patch on the occipital scalp following cerebral angiography with fistula embolization under fluoroscopy. His presentations were compatible with radiation-induced alopecia. Herein, we also report a novel scalp dermoscopic finding of blue-grey dots in a target pattern around yellow dots and follicles, which we detected in the lesion of radiation-induced alopecia. PMID:28074164

  10. Delayed Radiation-Induced Vasculitic Leukoencephalopathy

    SciTech Connect

    Rauch, Philipp J.; Park, Henry S.; Knisely, Jonathan P.S.; Chiang, Veronica L.; Vortmeyer, Alexander O.

    2012-05-01

    Purpose: Recently, single-fraction, high-dosed focused radiation therapy such as that administered by Gamma Knife radiosurgery has been used increasingly for the treatment of metastatic brain cancer. Radiation therapy to the brain can cause delayed leukoencephalopathy, which carries its own significant morbidity and mortality. While radiosurgery-induced leukoencephalopathy is known to be clinically different from that following fractionated radiation, pathological differences are not well characterized. In this study, we aimed to integrate novel radiographic and histopathologic observations to gain a conceptual understanding of radiosurgery-induced leukoencephalopathy. Methods and Materials: We examined resected tissues of 10 patients treated at Yale New Haven Hospital between January 1, 2009, and June 30, 2010, for brain metastases that had been previously treated with Gamma Knife radiosurgery, who subsequently required surgical management of a symptomatic regrowing lesion. None of the patients showed pathological evidence of tumor recurrence. Clinical and magnetic resonance imaging data for each of the 10 patients were then studied retrospectively. Results: We provide evidence to show that radiosurgery-induced leukoencephalopathy may present as an advancing process that extends beyond the original high-dose radiation field. Neuropathologic examination of the resected tissue revealed traditionally known leukoencephalopathic changes including demyelination, coagulation necrosis, and vascular sclerosis. Unexpectedly, small and medium-sized vessels revealed transmural T-cell infiltration indicative of active vasculitis. Conclusions: We propose that the presence of a vasculitic component in association with radiation-induced leukoencephalopathy may facilitate the progressive nature of the condition. It may also explain the resemblance of delayed leukoencephalopathy with recurring tumor on virtually all imaging modalities used for posttreatment follow-up.

  11. Radar detection of radiation-induced ionization in air

    DOEpatents

    Gopalsami, Nachappa; Heifetz, Alexander; Chien, Hual-Te; Liao, Shaolin; Koehl, Eugene R.; Raptis, Apostolos C.

    2015-07-21

    A millimeter wave measurement system has been developed for remote detection of airborne nuclear radiation, based on electromagnetic scattering from radiation-induced ionization in air. Specifically, methods of monitoring radiation-induced ionization of air have been investigated, and the ionized air has been identified as a source of millimeter wave radar reflection, which can be utilized to determine the size and strength of a radiation source.

  12. [Update in radiation-induced neoplasms: genetic studies].

    PubMed

    Chauveinc, Laurent; Lefevre, Sandrine; Malfoy, Bernard; Dutrillaux, Bernard

    2002-02-01

    Radiation induced tumors are a possible (very) late complications of radiotherapy. The evaluation of the risks of radiation-induced tumors has been presented in different epidemiological studies, with the evaluation of the relative risk for different tissues. But, the genetic studies are rare, and no global theory exists. Two cytogenetic profiles are described, one with translocations and one with genetic material losses, evoking two different genetic evolutions. Two questions are stated. What are the radiation-induced genetic mechanisms? Is it possible to differentiate the radiation-induced and spontaneous tumors with genetic approaches? With 37 cytogenetic cases, 12 analyzed in our laboratory, the radiation-induced tumors were characterized by genetic material losses. An anti-oncogenic evolution is probable. A new molecularly study confirm these results. Only thyroid tumors do not have this evolution. For tumors with simple karyotype, like meningioma, radiation-induced tumors seem to be more complex than spontaneous tumors. But for the others, the differentiation is impossible to be done with cytogenetic. The mechanism of the chromosomic material losses in unknown, but some hypothesis are discussed.

  13. Systematic evaluation of brachial plexus injuries.

    PubMed

    Haynes, S

    1993-01-01

    Brachial plexus injuries offer a unique challenge to the athletic trainer because of their relatively high frequency rate in contact sports and because of the complexity of the neuroanatomy in the cervical area. During a game, athletic trainers must make a fast, accurate decision regarding a player's return to competition. It is imperative that the athletic trainer be able to quickly differentiate between minor injuries and more serious injuries warranting removal from the game and/or physician referral. A systematic approach to the evaluation of a brachial plexus injury is essential to ensure proper treatment. This paper will present a structured approach to an on-the-field assessment of brachial plexus injuries.

  14. Clinical and dosimetric factors of radiation-induced esophageal injury: Radiation-induced esophageal toxicity

    PubMed Central

    Qiao, Wen-Bo; Zhao, Yan-Hui; Zhao, Yan-Bin; Wang, Rui-Zhi

    2005-01-01

    AIM: To analyze the clinical and dosimetric predictive factors for radiation-induced esophageal injury in patients with non-small-cell lung cancer (NSCLC) during three-dimensional conformal radiotherapy (3D-CRT). METHODS: We retrospectively analyzed 208 consecutive patients (146 men and 62 women) with NSCLC treated with 3D-CRT. The median age of the patients was 64 years (range 35-87 years). The clinical and treatment parameters including gender, age, performance status, sequential chemotherapy, concurrent chemotherapy, presence of carinal or subcarinal lymph nodes, pretreatment weight loss, mean dose to the entire esophagus, maximal point dose to the esophagus, and percentage of volume of esophagus receiving >55 Gy were studied. Clinical and dosimetric factors for radiation-induced acute and late grade 3-5 esophageal injury were analyzed according to Radiation Therapy Oncology Group (RTOG) criteria. RESULTS: Twenty-five (12%) of the two hundred and eight patients developed acute or late grade 3-5 esophageal injury. Among them, nine patients had both acute and late grade 3-5 esophageal injury, two died of late esophageal perforation. Concurrent chemotherapy and maximal point dose to the esophagus ≥60 Gy were significantly associated with the risk of grade 3-5 esophageal injury. Fifty-four (26%) of the two hundred and eight patients received concurrent chemotherapy. Among them, 25 (46%) developed grade 3-5 esophageal injury (P = 0.0001<0.01). However, no grade 3-5 esophageal injury occurred in patients who received a maximal point dose to the esophagus <60 Gy (P = 0.0001<0.01). CONCLUSION: Concurrent chemotherapy and the maximal esophageal point dose ≥60 Gy are significantly associated with the risk of grade 3-5 esophageal injury in patients with NSCLC treated with 3D-CRT. PMID:15849822

  15. Magnetic resonance neurography of the brachial plexus

    PubMed Central

    Upadhyaya, Vaishali; Upadhyaya, Divya Narain; Kumar, Adarsh; Pandey, Ashok Kumar; Gujral, Ratni; Singh, Arun Kumar

    2015-01-01

    Magnetic Resonance Imaging (MRI) is being increasingly recognised all over the world as the imaging modality of choice for brachial plexus and peripheral nerve lesions. Recent refinements in MRI protocols have helped in imaging nerve tissue with greater clarity thereby helping in the identification, localisation and classification of nerve lesions with greater confidence than was possible till now. This article on Magnetic Resonance Neurography (MRN) is based on the authors’ experience of imaging the brachial plexus and peripheral nerves using these protocols over the last several years. PMID:26424974

  16. Radiation-induced myeloid leukemia in murine models

    PubMed Central

    2014-01-01

    The use of radiation therapy is a cornerstone of modern cancer treatment. The number of patients that undergo radiation as a part of their therapy regimen is only increasing every year, but this does not come without cost. As this number increases, so too does the incidence of secondary, radiation-induced neoplasias, creating a need for therapeutic agents targeted specifically towards incidence reduction and treatment of these cancers. Development and efficacy testing of these agents requires not only extensive in vitro testing but also a set of reliable animal models to accurately recreate the complex situations of radiation-induced carcinogenesis. As radiation-induced leukemic progression often involves genomic changes such as rearrangements, deletions, and changes in methylation, the laboratory mouse Mus musculus, with its fully sequenced genome, is a powerful tool in cancer research. This fact, combined with the molecular and physiological similarities it shares with man and its small size and high rate of breeding in captivity, makes it the most relevant model to use in radiation-induced leukemia research. In this work, we review relevant M. musculus inbred and F1 hybrid animal models, as well as methods of induction of radiation-induced myeloid leukemia. Associated molecular pathologies are also included. PMID:25062865

  17. What has changed in brachial plexus surgery?

    PubMed Central

    de Rezende, Marcelo Rosa; Silva, Gustavo Bersani; de Paula, Emygdio José Leomil; Junior, Rames Mattar; de Camargo, Olavo Pires

    2013-01-01

    Brachial plexus injuries, in all their severity and complexity, have been extensively studied. Although brachial plexus injuries are associated with serious and often definitive sequelae, many concepts have changed since the 1950s, when this pathological condition began to be treated more aggressively. Looking back over the last 20 years, it can be seen that the entire approach, from diagnosis to treatment, has changed significantly. Some concepts have become better established, while others have been introduced; thus, it can be said that currently, something can always be offered in terms of functional recovery, regardless of the degree of injury. Advances in microsurgical techniques have enabled improved results after neurolysis and have made it possible to perform neurotization, which has undoubtedly become the greatest differential in treating brachial plexus injuries. Improvements in imaging devices and electrical studies have allowed quick decisions that are reflected in better surgical outcomes. In this review, we intend to show the many developments in brachial plexus surgery that have significantly changed the results and have provided hope to the victims of this serious injury. PMID:23644864

  18. [Idiopathic brachial neuralgia after cesarean section].

    PubMed

    Rihane, B; Le Borgne, J M; Bélair, C

    2002-11-01

    We report a case of idiopathic brachial nevralgia of the right shoulder in a 30-year-old female, after caesarean section, under spinal anaesthesia. Two days after surgery, intense cervical pain appeared on the second day, associated with rapid collapse of muscular shoulder belt. Full recovery occurred in four months.

  19. The Mechanisms of Radiation-Induced Bystander Effect

    PubMed Central

    Najafi, M; Fardid, R; Hadadi, Gh; Fardid, M

    2014-01-01

    The radiation-induced bystander effect is the phenomenon which non-irradiated cells exhibit effects along with their different levels as a result of signals received from nearby irradiated cells. Responses of non-irradiated cells may include changes in process of translation, gene expression, cell proliferation, apoptosis and cells death. These changes are confirmed by results of some In-Vivo studies. Most well-known important factors affecting radiation-induced bystander effect include free radicals, immune system factors, expression changes of some genes involved in inflammation pathway and epigenetic factors. PMID:25599062

  20. Panretinal photocoagulation for radiation-induced ocular ischemia

    SciTech Connect

    Augsburger, J.J.; Roth, S.E.; Magargal, L.E.; Shields, J.A.

    1987-08-01

    We present preliminary findings on the effectiveness of panretinal photocoagulation in preventing neovascular glaucoma in eyes with radiation-induced ocular ischemia. Our study group consisted of 20 patients who developed radiation-induced ocular ischemia following cobalt-60 plaque radiotherapy for a choroidal or ciliary body melanoma. Eleven of the 20 patients were treated by panretinal photocoagulation shortly after the diagnosis of ocular ischemia, but nine patients were left untreated. In this non-randomized study, the rate of development of neovascular glaucoma was significantly lower (p = 0.024) for the 11 photocoagulated patients than for the nine who were left untreated.

  1. [Symptoms, diagnosis and treatment of radiation-induced enteritis].

    PubMed

    Sinkó, Dániel; Baranyai, Zsolt; Nemeskéri, Csaba; Teknos, Dániel; Jósa, Valéria; Hegedus, László; Mayer, Arpád

    2010-09-05

    The number of radiotherapy in the treatment of malignant diseases is increasing worldwide. During the radiotherapy of tumors in the minor pelvis and abdomen intestinal inflammation of different degree may occur even if special attention is paid. Irradiation to the minor pelvis causes in half of the cases radiation induced acute enteritis, whereas in 25% chronic enteritis and colitis will develop. Chronic enteritis following radiotherapy raises a number of diagnostic and therapeutic problems that can be solved only with cooperation of different specialties. Authors present a short review regarding therapeutical options of radiation induced enteritis.

  2. Radiation-induced xerostomia: pathophysiology, clinical course and supportive treatment.

    PubMed

    Guchelaar, H J; Vermes, A; Meerwaldt, J H

    1997-07-01

    Xerostomia, or oral dryness, is one of the most common complaints experienced by patients who have had radiotherapy of the oral cavity and neck region. The hallmarks of radiation-induced damage are acinar atrophy and chronic inflammation of the salivary glands. The early response, resulting in atrophy of the secretory cells without inflammation might be due to radiation-induced apoptosis. In contrast, the late response with inflammation could be a result of radiation-induced necrosis. The subjective complaint of a dry mouth appears to be poorly correlated with objective findings of salivary gland dysfunction. Xerostomia, with secondary symptoms of increased dental caries, difficulty in chewing, swallowing and speaking, and an increased incidence of oral candidiasis, can have a significant effect on the quality of life. At present there is no causal treatment for radiation-induced xerostomia. Temporary symptomatic relief can be offered by moistening agents and saliva substitutes, and is the only option for patients without residual salivary function. In patients with residual salivary function, oral administration of pilocarpine 5-10 mg three times a day is effective in increasing salivary flow and improving the symptoms of xerostomia, and this therapy should be considered as the treatment of choice. Effectiveness of sialogogue treatment requires residual salivary function, which emphasizes the potential benefit from sparing normal tissue during irradiation. The hypothesis concerning the existence of early apoptotic and late necrotic effects of irradiation on the salivary glands theoretically offers a way of achieving this goal.

  3. Obstructive jaundice due to radiation-induced hepatic duct stricture

    SciTech Connect

    Chandrasekhara, K.L.; Iyer, S.K.

    1984-10-01

    A case of obstructive jaundice due to radiation-induced hepatic duct stricture is reported. The patient received postoperative radiation for left adrenal carcinoma, seven years prior to this admission. The sequelae of hepatobiliary radiation and their management are discussed briefly.

  4. SPHINX Measurements of Radiation Induced Conductivity of Foam

    SciTech Connect

    Ballard, W.P.; Beutler, D.E.; Burt, M.; Dudley, K.J.; Stringer, T.A.

    1998-12-14

    Experiments on the SPHINX accelerator studying radiation-induced conductivity (RIC) in foam indicate that a field-exclusion boundary layer model better describes foam than a Maxwell-Garnett model that treats the conducting gas bubbles in the foam as modifying the dielectric constant. In both cases, wall attachment effects could be important but were neglected.

  5. Radiation-Induced Immune Modulation in Prostate Cancer

    DTIC Science & Technology

    2007-01-01

    postulate that radiation-induced TNFR I probably acts as a “ brake ” on immunity. Because of the high risk of the proposed experiment and high...the rest of body shielded. Tumor diameters were measured in three mutually orthogonal dimensions at 2–3 day intervals with a vernier caliper and the

  6. Prevention of Radiation-Induced Breast Cancer by Amifostine

    DTIC Science & Technology

    2009-01-01

    acetylcysteine and captopril . 4 Task 2. To determine if post-irradiation amifostine treatment can reduce the frequency of radiation-induced ductal...similar to amifostine but more suited to oral administration such as WR- 3689, WR151327, N-acetylcysteine and captopril . The first task is to

  7. Prevention of Radiation-Induced Breast Cancer by Amifostine

    DTIC Science & Technology

    2006-06-01

    acetylcysteine and captopril . 4 Task 2. To determine if post-irradiation amifostine treatment can reduce the frequency of radiation-induced ductal...similar to amifostine but more suited to oral administration such as WR- 3689, WR151327, N-acetylcysteine and captopril . The first task is to

  8. Prevention of Radiation-Induced Breast Cancer by Amifostine

    DTIC Science & Technology

    2007-12-01

    and captopril . 4 Task 2. To determine if post-irradiation amifostine treatment can reduce the frequency of radiation-induced ductal dysplasia...amifostine but more suited to oral administration such as WR- 3689, WR151327, N-acetylcysteine and captopril . The first task is to determine if

  9. Radiation-induced instability and its relation to radiation carcinogenesis

    NASA Technical Reports Server (NTRS)

    Ullrich, R. L.; Ponnaiya, B.

    1998-01-01

    PURPOSE: A model that identifies radiation-induced genetic instability as the earliest cellular event in the multi-step sequence leading to radiation-induced cancer was previously proposed. In this paper ongoing experiments are discussed which are designed to test this model and its predictions in mouse mammary epithelial cells. RESULTS: Several lines of evidence are presented that appear to support this model: first, the development of delayed mutations in p53 following irradiation in altered growth variants; secondly, the high frequencies for the induction of both instability and transformation following irradiation in mammary epithelial cells; and finally, the demonstration that susceptibility to the induction of cytogenetic instability is a heritable trait that correlates with susceptibility to transformation and radiation-induced mammary cancer. Mice resistant to transformation and mammary cancer development are also resistant to the development of instability after irradiation. In contrast, mice sensitive to transformation and cancer are also sensitive to the development of cytogenetic instability. CONCLUSIONS: Data from this laboratory and from the studies cited above suggest a specific, and perhaps unique, role for radiation-induced instability as a critical early event associated with initiation of the carcinogenic process.

  10. Poor outcome in radiation-induced constrictive pericarditis

    SciTech Connect

    Karram, T.; Rinkevitch, D.; Markiewicz, W. )

    1993-01-15

    The purpose was to compare the outcome of patients with radiation-induced constrictive pericarditis versus patients with constiction due to another etiology. Twenty patients with constrictive pericarditis were seen during 1975-1986 at a single medical center. Six had radiation-induced constrictive pericarditis (Group A). The etiology was idiopathic in ten subjects and secondary to carcinomatous encasement, chronic renal failure, purulent infection and tuberculosis in one patient each (Group B, N = 14). Meang age was 53.4 [+-] 15.5 years. Extensive pericardiectomy was performed in 3/6 Group A and 13/14 Group B patients. All Group A patients died, 4 weeks - 11 years post-diagnosis (median = 10 months). Two Group A patients died suddenly, one died post-operatively of respiratory failure, another of pneumonia and two of recurrent carcinoma. Thirteen Group B patients are alive (median follow-up = 72 months). The only death in this group was due to metastatic cancer. The poor outcome with radiation-induced constriction is probably multi-factorial. Poor surgical outcome is to be expected in patients with evidence of recurrent tumor, high-dose irradiation, pulmonary fibrosis or associated radiation-induced myocardinal, valvular or coronary damage.

  11. Radiation-induced augmentation of the immune response

    SciTech Connect

    Anderson, R.E.; Lefkovits, I.; Troup, G.M.

    1980-01-01

    Radiation-induced augmentation of the immune response has been shown to occur both in vivo and in vitro. Evidence is presented to implicate injury to an extremely radiosensitive T cell in the expression of this phenomenon. Experiments are outlined which could be employed to support or reflect this hypothesis.

  12. Data acquisition system used in radiation induced electrical degradation experiments

    SciTech Connect

    White, D.P.

    1995-04-01

    Radiation induced electrical degradation (RIED) of ceramic materials has recently been reported and is the topic of much research at the present time. The object of this report is to describe the data acquisition system for an experiment designed to study RIED at the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory.

  13. Radiation-induced nonlinear optical response of quartz fibers

    NASA Astrophysics Data System (ADS)

    Plaksin, O. A.

    2006-10-01

    The intensity of radiation-induced luminescence and transient optical losses in KU-1 (Russia) and K-3 (Japan) quartz glass optical tibers irradiated in a fast pulsed fission reactor (a pulse duration of 80 μs and a neutron flux up to 7 × 1016 cm 2 s 2) has been measured in the visible range. The intensity of the fast luminescence component nonlinearly depends on the neutron flux. The luminescence intensity and the transient optical losses depend on the probe light intensity. Suppression of radiation-induced luminescence is observed at wavelengths that are longer or shorter than the probe light wavelength. Light probing leads to an increase in transient optical losses and a more rapid recovery of transparency. A model of two photon fluxes is proposed to analyze the relationship of the effects of suppression of radiation-induced luminescence and the increase in optical losses upon light probing. The effect of suppression of radiation-induced luminescence can be used to control the optical properties of fibers in radiation fields.

  14. Risk and survival outcomes of radiation-induced CNS tumors.

    PubMed

    Lee, Jessica W; Wernicke, A Gabriella

    2016-08-01

    Patients treated with cranial radiation are at risk of developing secondary CNS tumors. Understanding the incidence, treatment, and long-term outcomes of radiation-induced CNS tumors plays a role in clinical decision-making and patient education. Additionally, as meningiomas and pituitary tumors have been detected at increasing rates across all ages and may potentially be treated with radiation, it is important to know and communicate the risk of secondary tumors in children and adults. After conducting an extensive literature search, we identified publications that report incidence and long-term outcomes of radiation-induced CNS tumors. We reviewed 14 studies in children, which reported that radiation confers a 7- to 10-fold increase in subsequent CNS tumors, with a 20-year cumulative incidence ranging from 1.03 to 28.9 %. The latency period for secondary tumors ranged from 5.5 to 30 years, with gliomas developing in 5-10 years and meningiomas developing around 15 years after radiation. We also reviewed seven studies in adults, where the two strongest studies showed no increased risk while the remaining studies found a higher risk compared to the general population. The latency period for secondary CNS tumors in adults ranged from 5 to 34 years. Treatment and long-term outcomes of radiation-induced CNS tumors have been documented in four case series, which did not conclusively demonstrate that secondary CNS tumors fared worse than primary CNS tumors. Radiation-induced CNS tumors remain a rare occurrence that should not by itself impede radiation treatment. Additional investigation is needed on the risk of radiation-induced tumors in adults and the long-term outcomes of these tumors.

  15. Treatment Options for Brachial Plexus Injuries

    PubMed Central

    Sakellariou, Vasileios I.; Badilas, Nikolaos K.; Stavropoulos, Nikolaos A.; Mazis, George; Kotoulas, Helias K.; Kyriakopoulos, Stamatios; Tagkalegkas, Ioannis; Sofianos, Ioannis P.

    2014-01-01

    The incidence of brachial plexus injuries is rapidly growing due to the increasing number of high-speed motor-vehicle accidents. These are devastating injuries leading to significant functional impairment of the patients. The purpose of this review paper is to present the available options for conservative and operative treatment and discuss the correct timing of intervention. Reported outcomes of current management and future prospects are also analysed. PMID:24967125

  16. Oligomer formation in the radiation-induced polymerization of styrene

    NASA Astrophysics Data System (ADS)

    Harayma, Hiroshi; Al-Sheikhly, Mohamad; Silverman, Joseph

    2003-12-01

    Analyses of the oligomers formed in radiation-induced polymerization of purified styrene were performed. The principal dimeric products were cis- and trans-diphenyl-cyclobutane with a relatively small amount of 1-phenyltetralin; the trimeric products were the optical isomers of 1-phenyl-4-[1'-phenylethyl-(1')]-tetralin in gamma-ray and 60 MeV proton irradiation. Oligomer formation increased with increasing dose, but more gradually than the linear formation of high polymer with dose. The yield was 0.25-3.1 μmol/J at low doses and decreased to an asymptotic value of 0.15 at higher doses. It appears that oligomers act as chain transfer agents during the polymerization reaction which would account for the observed decrease in molecular weight of the high polymer with increase in dose. Although the thermal and radiation-induced polymerization of styrene have different initiation steps, the oligomers produced by both reactions are similar in composition.

  17. Caffeine Markedly Enhanced Radiation-Induced Bystander Effects

    NASA Astrophysics Data System (ADS)

    Jiang, Erkang; Wu, Lijun

    2009-04-01

    In this paper it is shown that incubation with 2 mM caffeine enhanced significantly the MN (micronucleus) formation in both the 1 cGy α-particle irradiated and non-irradiated bystander regions. Moreover, caffeine treatment made the non-irradiated bystander cells more sensitive to damage signals. Treated by c-PTIO(2-(4-carboxy-phenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide), a nitric oxide (NO) scavenger, the MN frequencies were effectively inhibited, showing that nitric oxide might be very important in mediating the enhanced damage. These results indicated that caffeine enhanced the low dose α-particle radiation-induced damage in irradiated and non-irradiated bystander regions, and therefore it is important to investigate the relationship between the radiosensitizer and radiation-induced bystander effects (RIBE).

  18. Radioadaptive response for protection against radiation-induced teratogenesis.

    PubMed

    Okazaki, Ryuji; Ootsuyama, Akira; Norimura, Toshiyuki

    2005-03-01

    To clarify the characteristics of the radioadaptive response in mice, we compared the incidence of radiation-induced malformations in ICR mice. Pregnant ICR mice were exposed to a priming dose of 2 cGy (667 muGy/min) on day 9.5 of gestation and to a challenging dose of 2 Gy (1.04 Gy/min) 4 h later and were killed on day 18.5 of gestation. The incidence of malformations and prenatal death and fetal body weights were studied. The incidence of external malformations was significantly lower (by approximately 10%) in the primed (2 cGy + 2 Gy) mice compared to the unprimed (2 Gy alone) mice. However, there were no differences in the incidence of prenatal death or the skeletal malformations or the body weights between primed and unprimed mice. These results suggest that primary conditioning with low doses of radiation suppresses radiation-induced teratogenesis.

  19. Radiation-induced transient darkening of optically transparent polymers

    SciTech Connect

    Downey, S.W.; Builta, L.A.; Carlson, R.L.; Czuchlewski, S.J.; Moir, D.C.

    1986-11-15

    Results are presented for the radiation-induced transient darkening of thin organic polymer films normally used as Cerenkov light emissions sources. The radiation source is a 27-MeV, 10-..mu..C, 200-ns electron beam generated by the PHERMEX accelerator. The typical dose for a single pulse is 5 Mrad. At this dose, the broadband time-resolved percent transmission above 520 nm was measured for four common polymers: polyimide (Kapton-H), polyethylene terephthalate (Mylar), cellulose acetate, and high-density polyethylene. Kapton was found to darken the most and polyethylene darkened the least. The recovery time to normal transmission for Kapton was found to be greater than 10--20 ..mu..s. The radiation-induced attenuation coefficient is shown to depend on electronic band energy separation. The results show that Kapton is not the material of choice for a Cerenkov light source.

  20. Faecal microbiota transplantation protects against radiation-induced toxicity.

    PubMed

    Cui, Ming; Xiao, Huiwen; Li, Yuan; Zhou, Lixin; Zhao, Shuyi; Luo, Dan; Zheng, Qisheng; Dong, Jiali; Zhao, Yu; Zhang, Xin; Zhang, Junling; Lu, Lu; Wang, Haichao; Fan, Saijun

    2017-04-01

    Severe radiation exposure may cause acute radiation syndrome, a possibly fatal condition requiring effective therapy. Gut microbiota can be manipulated to fight against many diseases. We explored whether intestinal microbe transplantation could alleviate radiation-induced toxicity. High-throughput sequencing showed that gastrointestinal bacterial community composition differed between male and female mice and was associated with susceptibility to radiation toxicity. Faecal microbiota transplantation (FMT) increased the survival rate of irradiated animals, elevated peripheral white blood cell counts and improved gastrointestinal tract function and intestinal epithelial integrity in irradiated male and female mice. FMT preserved the intestinal bacterial composition and retained mRNA and long non-coding RNA expression profiles of host small intestines in a sex-specific fashion. Despite promoting angiogenesis, sex-matched FMT did not accelerate the proliferation of cancer cells in vivo FMT might serve as a therapeutic to mitigate radiation-induced toxicity and improve the prognosis of tumour patients after radiotherapy.

  1. Dose and volume impact on radiation-induced xerostomia.

    PubMed

    Marmiroli, Luca; Salvi, Giovanna; Caiazza, Adolfo; Di Rienzo, Luigi; Massaccesi, Mariangela; Murino, Paola; Macchia, Gabriella

    2005-01-01

    Radiation-induced xerostomia consists in the chronic dryness of the mouth caused by parotid gland irradiation. Parotid glands produce approximately 60% of saliva while the rest is secreted by submandibular and accessory salivary glands. Methods of measuring the salivary output are essentially represented by 99mTc-pertechnate scintigraphy or simpler albeit less accurate methods in stimulated or unstimulated saliva. There are subjective and objective criteria of classification and grading of the secretion of saliva. Radiation-induced xerostomia, namely the residual salivary gland function is evidently associated with the mean dose absorbed. The salivary output tends to decrease after the end of radiotherapy. The partial dose-volume is substantially correlated with the mean dose to the whole gland. As for ipsilateral irradiation for head and neck cancer, conformal RT or IMRT allow to spare the contralateral parotid gland without increasing the risk of contralateral nodal recurrences. The monitoring system of late toxicity used by the authors is presented.

  2. Prosthodontic management of radiation induced xerostomic patient using flexible dentures

    PubMed Central

    Murthy, Varsha; V, Yuvraj; Nair, Preeti P; Thomas, Shaji

    2012-01-01

    Xerostomia causes discomfort for complete denture wearers as the tissues become dry and friable due to lack of lubricating properties of saliva. Common problems faced by such patients are glossitis, mucositis, angular chelitis, dysgeusia and difficulty in chewing and swallowing. This case report describes a new method in addressing such issues by using flexible complete denture construction in radiation induced xerostomic patient with minimal tissue damage during and after denture construction procedures. PMID:22605708

  3. Heavy-ion radiation induced bystander effect in mice

    NASA Astrophysics Data System (ADS)

    Liang, Shujian; Sun, Yeqing; Zhang, Meng; Wang, Wei; Cui, Changna

    2012-07-01

    Radiation-induced bystander effect is defined as the induction of damage in neighboring non-hit cells by signals released from directly-irradiated cells. Recently, Low dose of high LET radiation induced bystander effects in vivo have been reported more and more. It has been indicated that radiation induced bystander effect was localized not only in bystander tissues but also in distant organs. Genomic, epigenetic, metabolomics and proteomics play significant roles in regulating heavy-ion radiation stress responses in mice. To identify the molecular mechanism that underlies bystander effects of heavy-ion radiation, the male mice head were exposed to 2000mGy dose of 12C heavy-ion radiation and the distant organ liver was detected on 1h, 6h, 12h and 24h after radiation, respectively. MSAP was used to monitor the level of polymorphic DNA methylation changes. The results show that heavy-ion irradiate mouse head can induce liver DNA methylation changes significantly. The percent of DNA methylation changes are time-dependent and highest at 6h after radiation. We also prove that the hypo-methylation changes on 1h and 6h after irradiation. But the expression level of DNA methyltransferase DNMT3a is not changed. UPLC/Synapt HDMS G2 was employed to detect the proteomics of bystander liver 1h after irradiation. 64 proteins are found significantly different between treatment and control group. GO process show that six of 64 which were unique in irradiation group are associated with apoptosis and DNA damage response. The results suggest that mice head exposed to heavy-ion radiation can induce damage and methylation pattern changed in distant organ liver. Moreover, our findings are important to understand the molecular mechanism of radiation induced bystander effects in vivo.

  4. Follistatin attenuates radiation-induced fibrosis in a murine model

    PubMed Central

    Forrester, Helen B.; de Kretser, David M.; Leong, Trevor; Hagekyriakou, Jim; Sprung, Carl N.

    2017-01-01

    Purpose Fibrosis can be a disabling, severe side effect of radiotherapy that can occur in patients, and for which there is currently no effective treatment. The activins, proteins which are members of the TGFβ superfamily, have a major role in stimulating the inflammatory response and subsequent fibrosis. Follistatin is an endogenous protein that binds the activins virtually irreversibly and inhibits their actions. These studies test if follistatin can attenuate the fibrotic response using a murine model of radiation-induced fibrosis. Experimental design C57BL/6 mice were subcutaneously injected with follistatin 24 hours prior to irradiation. Mice were irradiated in a 10 x 10 mm square area of the right hind leg with 35 Gy and were given follistatin 24 hours before radiation and three times a week for six months following. Leg extension was measured, and tissue was collected for histological and molecular analysis to evaluate the progression of the radiation-induced fibrosis. Results Leg extension was improved in follistatin treated mice compared to vehicle treated mice at six months after irradiation. Also, epidermal thickness and cell nucleus area of keratinocytes were decreased by the follistatin treatment compared to the cells in irradiated skin of control mice. Finally, the gene expression of transforming growth factor β1 (Tgfb1), and smooth muscle actin (Acta2) were decreased in the irradiated skin and Acta2 and inhibin βA subunit (Inhba) were decreased in the irradiated muscle of the follistatin treated mice. Conclusions Follistatin attenuated the radiation-induced fibrotic response in irradiated mice. These studies provide the data to support further investigation of the use of follistatin to reduce radiation-induced fibrosis in patients undergoing radiotherapy for cancer. PMID:28301516

  5. Thermodynamic models of radiation-induced processes in solids

    NASA Astrophysics Data System (ADS)

    Yurov, V. M.; Eremin, E. N.; Kasymov, S. S.; Laurinas, V. CH; Chernyavskii, A. V.

    2017-01-01

    A thermodynamic model is proposed to qualitatively describe the radiation-induced processes in solids: temperature dependence of the X-ray radio luminescence output, dependence of these processes on the excitation density, energy accumulating in a solid under exposure to ionizing radiation and its temperature dependence. The proposed model and the formula derived can be used to develop radiation-resistant and radiation-sensitive materials.

  6. Process and Radiation Induced Defects in Electronic Materials and Devices

    NASA Technical Reports Server (NTRS)

    Washington, Kenneth; Fogarty, T. N.

    1997-01-01

    Process and radiation induced defects are characterized by a variety of electrical techniques, including capacitance-voltage measurements and charge pumping. Separation of defect type into stacking faults, displacement damage, oxide traps, interface states, etc. and their related causes are discussed. The defects are then related to effects on device parameters. Silicon MOS technology is emphasized. Several reviews of radiation effects and silicon processing exist.

  7. Role of Neurotensin in Radiation-Induced Hypothermia in Rats

    DTIC Science & Technology

    1991-01-01

    variety of behavioral and physiolog- of Neurotensin in Radiation-induced Hypothermia in Rat.A- ical effects, including the stimulation of histamine relmeas...induction of hypothermia, after intracisternal or intraven- was examined. Intracerebroventricular (IafCV) adminis-tration of tricular administration...1S-4 7). ’The purposes of this study ne-urotensin produced dose-dependent hypoihermia. Histamine were to investigate the role of neurotensin in

  8. Modulation of Radiation-Induced Apoptosis by Thiolamines

    NASA Technical Reports Server (NTRS)

    Warters, R. L.; Roberts, J. C.; Wilmore, B. H.; Kelley, L. L.

    1997-01-01

    Exposure to the thiolamine radioprotector N-(2-mercaptoethyl)-1,3-propanediamine (WR-1065) induced apoptosis in the mouse TB8-3 hybridoma after 60-minute (LD(sub50) = 4.5mM) or during a 20-hour (LD(sub50) = 0.15 mM) exposure. In contrast, a 20-hour exposure to 17 mM L-cysteine or 10 mM cysteamine was required to induce 50 percent apoptosis within 20 hours. Apoptosis was not induced by either a 60-minute or 20-hour exposure to 10 mM of the thiazolidime prodrugs ribose-cysteine (RibCys) or ribose-cysteamine (RibCyst). Thiolamine-induced apoptosis appeared to be a p53-independent process since it was induced by WR-1065 exposure in human HL60 cells. Exposure to WR-1065 (4mM for 15 minutes) or cysteine (10mM for 60 minutes) before and during irradiation protected cells against the induction of both DNA double-strand breaks and apoptosis, while exposure to RibCys (10 mM for 3 hours) did not. Treatment with either WR-1065, cysteine, RibCys or RibCyst for 60 minutes beginning 60 minutes after irradiation did not affect the level of radiation-induced apoptosis. In contrast, treatment with either cysteine, cysteamine or RibCys for 20 hours beginning 60 minutes after irradiation enhanced radiation-induced apoptosis. Similar experiments could not be conducted with WR-1065 because of its extreme toxicity. Our results indicate that thiolamine enhancement of radiation-induced apoptosis is not involved in their previously reported capacity to reduce radiation-induced mutations.

  9. Modeling radiation induced segregation in Iron-Chromium alloys

    SciTech Connect

    Senninger, Oriane; Soisson, Frederic; Martinez Saez, Enrique; Nastar, Maylise; Fu, Chu-Chun; Brechet, Yves

    2015-10-16

    Radiation induced segregation in ferritic Fe-Cr alloys is studied by Atomistic Kinetic Monte Carlo simulations that include di usion of chemical species by vacancy and interstitial migration, recombination, and elimination at sinks. The parameters of the di usion model are tted to DFT calculations. Transport coe cients that control the coupling between di usion of defects and chemical species are measured in dilute and concentrated alloys. Radiation induced segregation near grain boundaries is directly simulated with this model. We nd that the di usion of vacancies toward sinks leads to a Cr depletion. Meanwhile, the di usion of self-interstitials causes an enrichment of Cr in the vicinity of sinks. For concentrations lower than 15%Cr, we predict that sinks will be enriched with Cr for temperatures lower than a threshold. When the temperature is above this threshold value, the sinks will be depleted in Cr. These results are compared to previous experimental studies and models. Cases of radiation induced precipitation and radiation accelerated precipitation are considered.

  10. Modeling radiation induced segregation in Iron-Chromium alloys

    DOE PAGES

    Senninger, Oriane; Soisson, Frederic; Martinez Saez, Enrique; ...

    2015-10-16

    Radiation induced segregation in ferritic Fe-Cr alloys is studied by Atomistic Kinetic Monte Carlo simulations that include di usion of chemical species by vacancy and interstitial migration, recombination, and elimination at sinks. The parameters of the di usion model are tted to DFT calculations. Transport coe cients that control the coupling between di usion of defects and chemical species are measured in dilute and concentrated alloys. Radiation induced segregation near grain boundaries is directly simulated with this model. We nd that the di usion of vacancies toward sinks leads to a Cr depletion. Meanwhile, the di usion of self-interstitials causesmore » an enrichment of Cr in the vicinity of sinks. For concentrations lower than 15%Cr, we predict that sinks will be enriched with Cr for temperatures lower than a threshold. When the temperature is above this threshold value, the sinks will be depleted in Cr. These results are compared to previous experimental studies and models. Cases of radiation induced precipitation and radiation accelerated precipitation are considered.« less

  11. Diagnosis and treatment of pain in plexopathy, radiculopathy, peripheral neuropathy and phantom limb pain. Evidence and recommendations from the Italian Consensus Conference on Pain on Neurorehabilitation.

    PubMed

    Ferraro, Francesco; Jacopetti, Marco; Spallone, Vincenza; Padua, Luca; Traballesi, Marco; Brunelli, Stefano; Cantarella, Cristina; Ciotti, Cristina; Coraci, Daniele; Dalla Toffola, Elena; Mandrini, Silvia; Morone, Giovanni; Pazzaglia, Costanza; Romano, Marcello; Schenone, Angelo; Togni, Rossella; Tamburin, Stefano

    2016-12-01

    Pain may affect all aspects of social life and reduce the quality of life. Neuropathic pain (NP) is common in patients affected by plexopathy, radiculopathy, mononeuropathy, peripheral neuropathy. Phantom limb pain (PLP) is a painful sensation that is common after amputation, and its pathophysiological mechanisms involve changes in the peripheral and central nervous system. Given the lack of conclusive evidence and specific guidelines on these topics, the aim of the Italian Consensus Conference on Pain on Neurorehabilitation (ICCPN) was to collect evidence and offer recommendations to answer currently open questions on the assessment and treatment of NP associated with the above conditions and PLP. When no evidence was available, recommendations were based on consensus between expert opinions. Current guidelines on the assessment and pharmacological treatment of NP can be applied to plexopathy, radiculopathy, mononeuropathy, peripheral neuropathy, while evidence for invasive treatments and physical therapy is generally poor because of the low quality of studies. Treatment of PLP is still unsatisfactory. Data on the functional outcome and impact of pain on neurorehabilitation outcome in these conditions are lacking. In most cases, a multidisciplinary approach is recommended to offer a better outcome and reduce side effects. High quality studies are requested to address the unmet needs in this field.

  12. Lateral approach for supraclavicular brachial plexus block

    PubMed Central

    Sahu, DK; Sahu, Anjana

    2010-01-01

    A lateral approach described by Volker Hempel and Dr. Dilip Kotharihas been further studied, evaluated and described in detail in the present study. The aim of this study was to evaluate lateral approach of supraclavicular brachial plexus block, mainly in terms of successes rate and complication rate. The study was conducted in secondary level hospital and tertiary level hospital from 2004 to 2008. It was a prospective nonrandomized open-level study. Eighty-two patients of both sexes, aged between 18 and 65 years with ASA Grade I and II scheduled to undergo elective major surgery of the upper limb below the midarm, were selected for this new lateral approach of brachial plexus block. The onset and duration of sensory and motor block, any complications and need for supplement anaesthesia were observed. Success and complication rate were calculated in percentage. Average onset and duration of sensory and motor block was calculated as mean ± SD and percentage. Out of 82 patients, 75 (92%) have got successful block with no significant complication in any case. PMID:20885867

  13. Measurements of prompt radiation induced conductivity in Teflon (PTFE).

    SciTech Connect

    Hartman, E. Frederick; Zarick, Thomas Andrew; Sheridan, Timothy J.; Preston, E.

    2013-05-01

    We performed measurements of the prompt radiation induced conductivity (RIC) in thin samples of Teflon (PTFE) at the Little Mountain Medusa LINAC facility in Ogden, UT. Three mil (76.2 microns) samples were irradiated with a 0.5 %CE%BCs pulse of 20 MeV electrons, yielding dose rates of 1E9 to 1E11 rad/s. We applied variable potentials up to 2 kV across the samples and measured the prompt conduction current. Details of the experimental apparatus and analysis are reported in this report on prompt RIC in Teflon.

  14. Skeletal Scintigraphy in Radiation-Induced Fibrosis With Lymphedema.

    PubMed

    Wang, Jieqi; Iranmanesh, Arya M; Oates, M Elizabeth

    2017-03-01

    Despite increasing reliance on CT, MRI, and FDG PET/CT for oncological imaging, whole-body skeletal scintigraphy remains a frontline modality for staging and surveillance of osseous metastatic disease. We present a 54-year-old woman with metastatic breast cancer who received palliative external-beam radiation to the left ilium. Serial follow-up Tc-MDP bone scans demonstrated progressive soft-tissue uptake in her left lower extremity, extending from thigh to leg, with associated enlargement and skin thickening, consistent with lymphedema related to radiation-induced fibrosis. Correlative abdominopelvic CT scans confirmed fibrotic changes in the left thigh.

  15. Facial reconstruction for radiation-induced skin cancer

    SciTech Connect

    Panje, W.R.; Dobleman, T.J. )

    1990-04-01

    Radiation-induced skin cancers can be difficult to diagnose and treat. Typically, a patient who has received orthovoltage radiotherapy for disorders such as acne, eczema, tinea capitis, skin tuberculosis, and skin cancer can expect that aggressive skin cancers and chronic radiodermatitis may develop subsequently. Cryptic facial cancers can lead to metastases and death. Prophylactic widefield excision of previously irradiated facial skin that has been subject to multiple recurrent skin cancers is suggested as a method of deterring future cutaneous malignancy and metastases. The use of tissue expanders and full-thickness skin grafts offers an expedient and successful method of subsequent reconstruction.

  16. Challenges and Opportunities in Radiation-induced Hemorrhagic Cystitis

    PubMed Central

    Zwaans, Bernadette M.M.; Nicolai, Heinz G.; Chancellor, Michael B.; Lamb, Laura E.

    2016-01-01

    As diagnosis and treatment of cancer is improving, medical and social issues related to cancer survivorship are becoming more prevalent. Hemorrhagic cystitis (HC), a rare but serious disease that may affect patients after pelvic radiation or systemic chemotherapy, has significant unmet medical needs. Although no definitive treatment is currently available, various interventions are employed for HC. Effects of nonsurgical treatments for HC are of modest success and studies aiming to control radiation-induced bladder symptoms are lacking. In this review, we present current and advanced therapeutic strategies for HC to help cancer survivors deal with long-term urologic health issues. PMID:27601964

  17. Radiation-Induced Intraspinal Chondrosarcoma: A Case Report

    PubMed Central

    Obid, Peter; Vierbuchen, Mathias; Wolf, Eduard; Reichl, Michael; Niemeyer, Thomas; Übeyli, Hüseyin; Richter, Alexander

    2015-01-01

    Study Design Case report and review of the literature. Objective To report a unique case of an intraspinal chondrosarcoma that was diagnosed 18 years after radiotherapy for a cervical carcinoma and its remarkably unusual clinical presentation. Methods A retrospective case description of an intraspinal mass lesion that occurred 6 weeks after previous spinal surgery. Results Within ∼9 weeks, the tumor had infiltrated the peritoneal cavity and reached the lumbar subcutaneous tissue. Conclusion Radiation-induced sarcomas are rare, are highly aggressive, and may be difficult to diagnose. Furthermore, the only means of achieving long-term survival is through early and extensive surgery. PMID:26430606

  18. Radiation-induced breast angiosarcoma: a case report

    PubMed Central

    Tato-Varela, Sara; Albalat-Fernández, Rosa; Pabón-Fernández, Sara; Núñez-García, Diego; Calle-Marcos, Manolo La

    2016-01-01

    Radiation-induced breast angiosarcoma is a severe but rare late complication in the breast-preserving management of breast cancer through surgery and radiotherapy [1]. Often the initial diagnosis of this entity is complex given its relatively anodyne nature and usually being present in the form of typically multifocal reddish-purple papular skin lesions [2]. Because of the low incidence of this tumour, there is a limited number of studies regarding its optimal therapeutic management [3]. The preferred treatment is aggressive surgical removal and the prognosis is poor with an overall survival rate of 12–20% at five years [4]. PMID:28101140

  19. Radiation-Induced Premelting of Ice at Silica Interfaces

    SciTech Connect

    Schoeder, S.; Reichert, H.; Schroeder, H.; Mezger, M.; Okasinski, J. S.; Dosch, H.; Honkimaeki, V.; Bilgram, J.

    2009-08-28

    The existence of surface and interfacial melting of ice below 0 deg. C has been confirmed by many different experimental techniques. Here we present a high-energy x-ray reflectivity study of the interfacial melting of ice as a function of both temperature and x-ray irradiation dose. We found a clear increase of the thickness of the quasiliquid layer with the irradiation dose. By a systematic x-ray study, we have been able to unambiguously disentangle thermal and radiation-induced premelting phenomena. We also confirm the previously announced very high water density (1.25 g/cm{sup 3}) within the emerging quasiliquid layer.

  20. Measurements of prompt radiation induced conductivity of Kapton.

    SciTech Connect

    Preston, Eric F.; Zarick, Thomas Andrew; Sheridan, Timothy J.; Hartman, E. Frederick; Stringer, Thomas Arthur

    2010-10-01

    We performed measurements of the prompt radiation induced conductivity in thin samples of Kapton (polyimide) at the Little Mountain Medusa LINAC facility in Ogden, UT. Three mil samples were irradiated with a 0.5 {mu}s pulse of 20 MeV electrons, yielding dose rates of 1E9 to 1E10 rad/s. We applied variable potentials up to 2 kV across the samples and measured the prompt conduction current. Analysis rendered prompt conductivity coefficients between 6E-17 and 2E-16 mhos/m per rad/s, depending on the dose rate and the pulse width.

  1. Pathology and biology of radiation-induced cardiac disease

    PubMed Central

    Tapio, Soile

    2016-01-01

    Heart disease is the leading global cause of death. The risk for this disease is significantly increased in populations exposed to ionizing radiation, but the mechanisms are not fully elucidated yet. This review aims to gather and discuss the latest data about pathological and biological consequences in the radiation-exposed heart in a comprehensive manner. A better understanding of the molecular and cellular mechanisms underlying radiation-induced damage in heart tissue and cardiac vasculature will provide novel targets for therapeutic interventions. These may be valuable for individuals clinically or occupationally exposed to varying doses of ionizing radiation. PMID:27422929

  2. Mechanisms of Radiation Induced Effects in Carbon Nanotubes

    DTIC Science & Technology

    2016-10-01

    8725 John J. Kingman Road, MS 6201 Fort Belvoir, VA 22060-6201 T E C H N IC A L R E P O R T DTRA-TR-17-5 Mechanisms of Radiation-Induced...CLASSIFICATION OF: a. REPORT b. ABSTRACT c. THIS PAGE 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 00-10-2016 Final Oct 5, 2010 - Dec 31, 2015 Mechanisms of...primary outcome of this program, determined using both theory and experiment, has been a complete understanding of the mechanisms of radiation damage

  3. Radiation-induced skin carcinomas of the head and neck

    SciTech Connect

    Ron, E.; Modan, B.; Preston, D.; Alfandary, E.; Stovall, M.; Boice, J.D. Jr. )

    1991-03-01

    Radiation exposures to the scalp during childhood for tinea capitis were associated with a fourfold increase in skin cancer, primarily basal cell carcinomas, and a threefold increase in benign skin tumors. Malignant melanoma, however, was not significantly elevated. Overall, 80 neoplasms were identified from an extensive search of the pathology logs of all major hospitals in Israel and computer linkage with the national cancer registry. Radiation dose to the scalp was computed for over 10,000 persons irradiated for ringworm (mean 7 Gy), and incidence rates were contrasted with those observed in 16,000 matched comparison subjects. The relative risk of radiogenic skin cancer did not differ significantly between men or women or by time since exposure; however, risk was greatest following exposures in early childhood. After adjusting for sex, ethnic origin, and attained age, the estimated excess relative risk was 0.7 per Gy and the average excess risk over the current follow-up was 0.31/10(4) PY-Gy. The risk per Gy of radiation-induced skin cancer was intermediate between the high risk found among whites and no risk found among blacks in a similar study conducted in New York City. This finding suggests the role that subsequent exposure to uv radiation likely plays in the expression of a potential radiation-induced skin malignancy.

  4. Nature of radiation-induced defects in quartz

    SciTech Connect

    Wang, Bu; Yu, Yingtian; Bauchy, Mathieu; Pignatelli, Isabella; Sant, Gaurav

    2015-07-14

    Although quartz (α-form) is a mineral used in numerous applications wherein radiation exposure is an issue, the nature of the atomistic defects formed during radiation-induced damage has not been fully clarified. Especially, the extent of oxygen vacancy formation is still debated, which is an issue of primary importance as optical techniques based on charged oxygen vacancies have been utilized to assess the level of radiation damage in quartz. In this paper, molecular dynamics simulations are applied to study the effects of ballistic impacts on the atomic network of quartz. We show that the defects that are formed mainly consist of over-coordinated Si and O, as well as Si–O connectivity defects, e.g., small Si–O rings and edge-sharing Si tetrahedra. Oxygen vacancies, on the contrary, are found in relatively low abundance, suggesting that characterizations based on E′ centers do not adequately capture radiation-induced structural damage in quartz. Finally, we evaluate the dependence on the incident energy, of the amount of each type of the point defects formed, and quantify unambiguously the threshold displacement energies for both O and Si atoms. These results provide a comprehensive basis to assess the nature and extent of radiation damage in quartz.

  5. Inhibition of radiation-induced polyuria by histamine receptor antagonists

    SciTech Connect

    Donlon, M.A.; Melia, J.A.; Helgeson, E.A.; Wolfe, W.W.

    1986-03-01

    In previous studies the authors have demonstrated that gamma radiation results in polyuria, which is preceded by polydypsia. This suggests that the increased thirst elicited by radiation causes increased urinary volume (UV). Histamine, which is released following radiation exposure, also elicits drinking by nonirradiated rats when administered exogenously. In this study the authors have investigated both the role of water deprivation and the effect of histamine receptor antagonists (HRA) on radiation-induced polyuria. Sprague-Dawley rats were housed individually in metabolic cages. Water was allowed ad libitum except in deprivation experiments where water was removed for 24 hr immediately following radiation. Cimetidine (CIM), an H2 HRA, and dexbromopheniramine (DXB), an H1 HRA, were administered i.p. (16 and 1 mg/kg, respectively) 30 min prior to irradiation (950 rads from a cobalt source). UV was determined at 24-hr intervals for 3 days preceding irradiation and 24 hr postirradiation. UV in DXB treated rats was significantly reduced 24 hr postirradiation (CON = 427 +/- 54%; DXB = 247 +/- 39% of preirradiated CON) compared to postirradiation control values. CIM did not affect postirradiation UV. These data suggest that radiation-induced polyuria is caused by polydypsia which is, in part, mediated by histamine induced by an H1 receptor.

  6. The thermal stability of radiation-induced defects in illite

    NASA Astrophysics Data System (ADS)

    Riegler, T.; Allard, T.; Beaufort, D.; Cantin, J.-L.; von Bardeleben, H. J.

    2016-01-01

    High-purity illite specimens from the Mesoproterozoic unconformity-related uranium deposits of Kiggavik, Thelon basin, Nunavut (Canada), and Shea Creek (Athabasca basin, Saskatchewan, Canada) have been studied using electron paramagnetic resonance spectroscopy to determine the thermal stability of the main radiation-induced defects and question the potential of using illite as a natural dosimeter. The observed spectra are complex as they can show in the same region several contributions: (1) an unstable native defect, (2) the main stable defect named Ai by reference to a previous study (Morichon et al. in Phys Chem Minerals 35:339-346, 2008), (3) a signal at g = 2.063 assigned to a new defect, not yet fully characterized, named Ai2 center and (4) impurities such as vanadyl complex or divalent manganese. Isochronal heating shows that the new signal corresponds to a stable species. Isothermal heating experiments at 400 and 450 °C provide values of half-life extrapolated at room temperature and activation energy of 1.9-29,109 years and 1.3-1.4 eV, respectively, corresponding to the Ai center. These parameters allow the use of stable radiation-induced defects as a record of radioactivity down to the Paleoproterozoic period.

  7. Radiation-induced dural fibrosarcoma with unusually short latent period

    SciTech Connect

    Ghatak, N.R.; Aydin, F.; Leshner, R.T. Tulane Univ., New Orleans, LA )

    1993-05-01

    Although rare, the occurrence of radiation-induced intracranial neoplasms of various types is well known. Among these tumors, fibrosarcomas, especially in the region of seila turcica, seem to be the most common type. These tumors characteristically occur after a long latent period, usually several years, following radiation therapy. The authors now report a case of apparently radiation-induced fibrosarcoma with some unusual features in a 10-year-old boy who was treated with radiation for medulloblastoma. He received a total dose of 53.2 Gy radiation delivered at 1.8 per fraction with 6 MV acceleration using the standard craniospinal technique. An MRI at 15 months after the completion of radiotherapy showed a mass over the cerebral convexity, which increased two-fold in size within a period of 4 months. A well circumscribed tumor was removed from the fronto-parietal convexity. The tumor measured 5x4.5x1.5 cm and was attached to the dura with invasion of the overlying bone. Histologically, it displayed the characteristic features of a low-grade fibrosarcoma. The patient remains free of tumor 18 months after the surgery. This case emphasizes the potential risk for the development of a second neoplasm following therapeutic radiation and also documents, to the authors' knowledge, the shortest latent period reported so far between administration of radiotherapy and development of an intracranial tumor.

  8. Radiation-induced recurrent intestinal pseudo-obstruction

    SciTech Connect

    Conklin, J.L.; Anuras, S.

    1981-06-01

    The syndrome of intestinal pseudo-obstruction is a complex of signs and symptoms of intestinal obstruction without evidence of mechanical obstruction of the intestinal lumen. A patient with radiation-induced intestinal pseudoobstruction is described. The patient is a 74-year old woman with a history of chronic diarrhea, recurrent episodes of crampy abdominal pain, nausea and vomiting since receiving a 13,000 rad radiation dose to the pelvis in 1954. She has been hospitalized on many occasions for symptoms and signs of bowel obstruction. Upper gastrointestinal contrast roentgenograms with small bowel follow-through done during these episodes revealed multiple dilated loops of small bowel with no obstructing lesion. Barium enemas revealed no obstructing lesion. Each episode resolved with conservative therapy. Other secondary causes for intestinal pseudo-obstruction were ruled out in our patient. She gave no history of familial gastrointestinal disorders. Although postirradiation motility abnormalities have been demonstrated experimentally this is the first report of radiation induced intestinal pseudo-obstruction.

  9. Sensitivity to Radiation-Induced Cancer in Hemochromatosis

    SciTech Connect

    Bull. Richard J.; Anderson, Larry E.

    2000-06-01

    The objectives of this pilot project using HFE-knockout homozygotes and heterozygotes are to (1) determine whether the knock-out mice have greater sensitivity to radiation-induced cancer of the colon, liver and breast, (2) establish the dependence of this sensitivity on the accumulation of iron, (3) determine the extent to which cell replication and apoptosis occur in these target tissues with varying iron load, and (4) correlate the increases in sensitivity with changes in insulin-related signaling in tumors and normal tissue from each target organ. Three experimental designs will be used in the pilot project. The sequence of experiments is designed to first explore the influence of iron load on the response and demonstrate that HFE knockout mice are more sensitive than the wild type to radiation-induced cancer in one or more of three target tissues (liver, colon and breast). The dose response relationships with a broader set of radiation doses will be explored in the second experiment. The final experiment is designed to explore the extent to which heterozygotes display the increased susceptibility to cancer induction and to independently assess the importance of iron load to the initiation versus promotion of tumors.

  10. Radiation-induced genomic instability in Caenorhabditis elegans.

    PubMed

    Huumonen, Katriina; Immonen, Hanna-Kaisa; Baverstock, Keith; Hiltunen, Mikko; Korkalainen, Merja; Lahtinen, Tapani; Parviainen, Juha; Viluksela, Matti; Wong, Garry; Naarala, Jonne; Juutilainen, Jukka

    2012-10-09

    Radiation-induced genomic instability has been well documented, particularly in vitro. However, the understanding of its mechanisms and their consequences in vivo is still limited. In this study, Caenorhabditis elegans (C. elegans; strain CB665) nematodes were exposed to X-rays at doses of 0.1, 1, 3 or 10Gy. The endpoints were measured several generations after exposure and included mutations in the movement-related gene unc-58, alterations in gene expression analysed with oligoarrays containing the entire C. elegans genome, and micro-satellite mutations measured by capillary electrophoresis. The progeny of the irradiated nematodes showed an increased mutation frequency in the unc-58 gene, with a maximum response observed at 1Gy. Significant differences were also found in gene expression between the irradiated (1Gy) and non-irradiated nematode lines. Differences in gene expression did not show clear clustering into certain gene categories, suggesting that the instability might be a chaotic process rather than a result of changes in the function of few specific genes such as, e.g., those responsible for DNA repair. Increased heterogeneity in gene expression, which has previously been described in irradiated cultured human lymphocytes, was also observed in the present study in C. elegans, the coefficient of variation of gene expression being higher in the progeny of irradiated nematodes than in control nematodes. To the best of our knowledge, this is the first publication reporting radiation-induced genomic instability in C. elegans.

  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. DNA damage in cells exhibiting radiation-induced genomic instability

    DOE PAGES

    Keszenman, Deborah J.; Kolodiuk, Lucia; Baulch, Janet E.

    2015-02-22

    Cells exhibiting radiation induced genomic instability exhibit varied spectra of genetic and chromosomal aberrations. Even so, oxidative stress remains a common theme in the initiation and/or perpetuation of this phenomenon. Isolated oxidatively modified bases, abasic sites, DNA single strand breaks and clustered DNA damage are induced in normal mammalian cultured cells and tissues due to endogenous reactive oxygen species generated during normal cellular metabolism in an aerobic environment. While sparse DNA damage may be easily repaired, clustered DNA damage may lead to persistent cytotoxic or mutagenic events that can lead to genomic instability. In this study, we tested the hypothesismore » that DNA damage signatures characterised by altered levels of endogenous, potentially mutagenic, types of DNA damage and chromosomal breakage are related to radiation-induced genomic instability and persistent oxidative stress phenotypes observed in the chromosomally unstable progeny of irradiated cells. The measurement of oxypurine, oxypyrimidine and abasic site endogenous DNA damage showed differences in non-double-strand breaks (DSB) clusters among the three of the four unstable clones evaluated as compared to genomically stable clones and the parental cell line. These three unstable clones also had increased levels of DSB clusters. The results of this study demonstrate that each unstable cell line has a unique spectrum of persistent damage and lead us to speculate that alterations in DNA damage signaling and repair may be related to the perpetuation of genomic instability.« less

  13. DNA damage in cells exhibiting radiation-induced genomic instability

    SciTech Connect

    Keszenman, Deborah J.; Kolodiuk, Lucia; Baulch, Janet E.

    2015-02-22

    Cells exhibiting radiation induced genomic instability exhibit varied spectra of genetic and chromosomal aberrations. Even so, oxidative stress remains a common theme in the initiation and/or perpetuation of this phenomenon. Isolated oxidatively modified bases, abasic sites, DNA single strand breaks and clustered DNA damage are induced in normal mammalian cultured cells and tissues due to endogenous reactive oxygen species generated during normal cellular metabolism in an aerobic environment. While sparse DNA damage may be easily repaired, clustered DNA damage may lead to persistent cytotoxic or mutagenic events that can lead to genomic instability. In this study, we tested the hypothesis that DNA damage signatures characterised by altered levels of endogenous, potentially mutagenic, types of DNA damage and chromosomal breakage are related to radiation-induced genomic instability and persistent oxidative stress phenotypes observed in the chromosomally unstable progeny of irradiated cells. The measurement of oxypurine, oxypyrimidine and abasic site endogenous DNA damage showed differences in non-double-strand breaks (DSB) clusters among the three of the four unstable clones evaluated as compared to genomically stable clones and the parental cell line. These three unstable clones also had increased levels of DSB clusters. The results of this study demonstrate that each unstable cell line has a unique spectrum of persistent damage and lead us to speculate that alterations in DNA damage signaling and repair may be related to the perpetuation of genomic instability.

  14. [Radiation-induced genomic instability: phenomenon, molecular mechanisms, pathogenetic significance].

    PubMed

    Mazurik, V K; Mikhaĭlov, V F

    2001-01-01

    The recent data on the radiation-induced genome instability as a special state of progeny of cells irradiated in vitro as well as after a whole body exposure to ionizing radiation, that make these cells considerably different from normal, unirradiated cells, were considered. This state presents a number of cytogenetical, molecular-biological, cytological and biochemical manifestations untypical for normal cells. The state is controlled by the mechanisms of regulation of checkpoints of cell cycle, and apoptosis, that is under gene p53 control. The proof has been found that this state transfers from irradiated maternal cells to their surviving progeny by the epigenetical mechanisms and would exist until the cells restore the original state of response on the DNA damage. From the point of view of the genome instability conception, that considers the chromatine rearrangement as the adaptive-evolution mechanism of adaptation of the species to changeable environmental conditions, the radiation-induced genome instability may be considered as transition of irradiated progeny to the state of read these to adaptation changes with two alternative pathways. The first leads to adaptation to enviromental conditions and restoring of normal cell functions. The second presents the cell transition into the transformed state with remain genome instability and with increase of tumour growth probability.

  15. Contribution of radiation-induced, nitric oxide-mediated bystander effect to radiation-induced adaptive response.

    NASA Astrophysics Data System (ADS)

    Matsumoto, H.; Ohnishi, T.

    There has been a recent upsurge of interest in radiation-induced adaptive response and bystander effect which are specific modes in stress response to low-dose low-dose rate radiation Recently we found that the accumulation of inducible nitric oxide NO synthase iNOS in wt p53 cells was induced by chronic irradiation with gamma rays followed by acute irradiation with X-rays but not by each one resulting in an increase in nitrite concentrations of medium It is suggested that the accumulation of iNOS may be due to the depression of acute irradiation-induced p53 functions by pre-chronic irradiation In addition we found that the radiosensitivity of wt p53 cells against acute irradiation with X-rays was reduced after chronic irradiation with gamma rays This reduction of radiosensitivity of wt p53 cells was nearly completely suppressed by the addition of NO scavenger carboxy-PTIO to the medium This reduction of radiosensitivity of wt p53 cells is just radiation-induced adaptive response suggesting that NO-mediated bystander effect may considerably contribute to adaptive response induced by radiation

  16. Radiation induced genome instability: multiscale modelling and data analysis

    NASA Astrophysics Data System (ADS)

    Andreev, Sergey; Eidelman, Yuri

    2012-07-01

    Genome instability (GI) is thought to be an important step in cancer induction and progression. Radiation induced GI is usually defined as genome alterations in the progeny of irradiated cells. The aim of this report is to demonstrate an opportunity for integrative analysis of radiation induced GI on the basis of multiscale modelling. Integrative, systems level modelling is necessary to assess different pathways resulting in GI in which a variety of genetic and epigenetic processes are involved. The multilevel modelling includes the Monte Carlo based simulation of several key processes involved in GI: DNA double strand breaks (DSBs) generation in cells initially irradiated as well as in descendants of irradiated cells, damage transmission through mitosis. Taking the cell-cycle-dependent generation of DNA/chromosome breakage into account ensures an advantage in estimating the contribution of different DNA damage response pathways to GI, as to nonhomologous vs homologous recombination repair mechanisms, the role of DSBs at telomeres or interstitial chromosomal sites, etc. The preliminary estimates show that both telomeric and non-telomeric DSB interactions are involved in delayed effects of radiation although differentially for different cell types. The computational experiments provide the data on the wide spectrum of GI endpoints (dicentrics, micronuclei, nonclonal translocations, chromatid exchanges, chromosome fragments) similar to those obtained experimentally for various cell lines under various experimental conditions. The modelling based analysis of experimental data demonstrates that radiation induced GI may be viewed as processes of delayed DSB induction/interaction/transmission being a key for quantification of GI. On the other hand, this conclusion is not sufficient to understand GI as a whole because factors of DNA non-damaging origin can also induce GI. Additionally, new data on induced pluripotent stem cells reveal that GI is acquired in normal mature

  17. Radiation-induced lichen sclerosus of the vulva : First report in the medical literature.

    PubMed

    Edwards, Lisa R; Privette, Emily D; Patterson, James W; Tchernev, Georgi; Chokoeva, Anastasiya Atanasova; Wollina, Uwe; Lotti, Torello; Wilson, Barbara B

    2017-03-01

    A 67-year-old woman presented with a firm plaque in the perineal region, 16 months after diagnosis of a high-grade basaloid squamous cell carcinoma of the vagina and treatment by external beam radiation therapy and vaginal cuff brachytherapy. The differential diagnosis included radiation-induced morphea, radiation dermatitis, or, possibly, radiation-induced lichen sclerosus. Biopsy findings, including special staining, confirmed the diagnosis of radiation-induced lichen sclerosus. To our knowledge, this is the first report of radiation-induced lichen sclerosus of the vulvar region.

  18. Radiation-induced bystander effect: early process and rapid assessment.

    PubMed

    Wang, Hongzhi; Yu, K N; Hou, Jue; Liu, Qian; Han, Wei

    2015-01-01

    Radiation-induced bystander effect (RIBE) is a biological process that has received attention over the past two decades. RIBE refers to a plethora of biological effects in non-irradiated cells, including induction of genetic damages, gene expression, cell transformation, proliferation and cell death, which are initiated by receiving bystander signals released from irradiated cells. RIBE brings potential hazards to normal tissues in radiotherapy, and imparts a higher risk from low-dose radiation than we previously thought. Detection with proteins related to DNA damage and repair, cell cycle control, proliferation, etc. have enabled rapid assessment of RIBE in a number of research systems such as cultured cells, three-dimensional tissue models and animal models. Accumulated experimental data have suggested that RIBE may be initiated rapidly within a time frame as short as several minutes after radiation. These have led to the requirement of techniques capable of rapidly assessing RIBE itself as well as assessing the early processes involved.

  19. The Dose Window for Radiation-Induced Protective Adaptive Responses

    PubMed Central

    Mitchel, Ronald E. J.

    2009-01-01

    Adaptive responses to low doses of low LET radiation occur in all organisms thus far examined, from single cell lower eukaryotes to mammals. These responses reduce the deleterious consequences of DNA damaging events, including radiation-induced or spontaneous cancer and non-cancer diseases in mice. The adaptive response in mammalian cells and mammals operates within a certain window that can be defined by upper and lower dose thresholds, typically between about 1 and 100 mGy for a single low dose rate exposure. However, these thresholds for protection are not a fixed function of total dose, but also vary with dose rate, additional radiation or non-radiation stressors, tissue type and p53 functional status. Exposures above the upper threshold are generally detrimental, while exposures below the lower threshold may or may not increase either cancer or non-cancer disease risk. PMID:20585438

  20. Calculation of radiation-induced creep and stress relaxation

    NASA Astrophysics Data System (ADS)

    Nagakawa, Johsei

    1995-08-01

    Numerical calculation based on a computer simulation of point defect kinetics under stress was performed to predict radiation-induced deformation in an Inconel X-750 bolt in a LWR core and for a 316 stainless steel blanket in experimental fusion reactors with the water-coolant scenario. Although the displacement rate is rather low, modest irradiation creep with nearly linear stress dependence was predicted below 200 MPa at 300°C in the LWR core. This low stress dependence causes significant stress relaxation, which coincides with the experimental data to 2 dpa. An almost equal amount of enhanced irradiation creep strain was predicted at 60°C in both solution annealed and cold worker 316 stainless steel in the water-cooled blanket. The stress relaxation is practically not expected without irradiation in both the cases, but the calculation predicts that it is definitely expected under irradiation.

  1. Measurements of prompt radiation induced conductivity of alumina and sapphire

    SciTech Connect

    Hartman, E. Frederick; Zarick, Thomas Andrew; Sheridan, Timothy J.; Preston, Eric F.

    2011-04-01

    We performed measurements of the prompt radiation induced conductivity in thin samples of Alumina and Sapphire at the Little Mountain Medusa LINAC facility in Ogden, UT. Five mil thick samples were irradiated with pulses of 20 MeV electrons, yielding dose rates of 1E7 to 1E9 rad/s. We applied variable potentials up to 1 kV across the samples and measured the prompt conduction current. Analysis rendered prompt conductivity coefficients between 1E10 and 1E9 mho/m/(rad/s), depending on the dose rate and the pulse width for Alumina and 1E7 to 6E7 mho/m/(rad/s) for Sapphire.

  2. Factors that modify risks of radiation-induced cancer

    SciTech Connect

    Fabrikant, J.I.

    1988-11-01

    The collective influence of biologic and physical factors that modify risks of radiation-induced cancer introduces uncertainties sufficient to deny precision of estimates of human cancer risk that can be calculated for low-dose radiation in exposed populations. The important biologic characteristics include the tissue sites and cell types, baseline cancer incidence, minimum latent period, time-to-tumor recognition, and the influence of individual host (age and sex) and competing etiologic influences. Physical factors include radiation dose, dose rate, and radiation quality. Statistical factors include time-response projection models, risk coefficients, and dose-response relationships. Other modifying factors include other carcinogens, and other biological sources (hormonal status, immune status, hereditary factors).

  3. Invertase immobilization onto radiation-induced graft copolymerized polyethylene pellets

    NASA Astrophysics Data System (ADS)

    de Queiroz, Alvaro Antonio Alencar; Vitolo, Michele; de Oliveira, Rômulo Cesar; Higa, Olga Zazuco

    1996-06-01

    The graft copolymer poly(ethylene-g-acrylic acid) (LDPE-g-AA) was prepared by radiation-induced graft copolymerization of acrylic acid onto low density polyethylene (LDPE) pellets, and characterized by infrared photoacoustic spectroscopy and scanning electron microscopy (SEM). The presence of the grafted poly(acrylic acid) (PAA) was established. Invertase was immobilized onto the graft polymer and the thermodynamic parameters of the soluble and immobilized enzyme were determined. The Michaelis constant, Km, and the maximum reaction velocity, Vmax, were determined for the free and the immobilized invertase. The Michaelis constant, Km was larger for the immobilized invertase than for the free enzyme, whereas Vmax was smaller for the immobilized invertase. The thermal stability of the immobilized invertase was higher than that of the free enzyme.

  4. Radiation-induced polymerization for the immobilization of penicillin acylase

    SciTech Connect

    Boccu, E.; Carenza, M.; Lora, S.; Palma, G.; Veronese, F.M.

    1987-06-01

    The immobilization of Escherichia coli penicillin acylase was investigated by radiation-induced polymerization of 2-hydroxyethyl methacrylate at low temperature. A leak-proof composite that does not swell in water was obtained by adding the cross-linking agent trimethylolpropane trimethacrylate to the monomer-aqueous enzyme mixture. Penicillin acylase, which was immobilized with greater than 70% yield, possessed a higher Km value toward the substrate 6-nitro-3-phenylacetamidobenzoic acid than the free enzyme form (Km = 1.7 X 10(-5) and 1 X 10(-5) M, respectively). The structural stability of immobilized penicillin acylase, as assessed by heat, guanidinium chloride, and pH denaturation profiles, was very similar to that of the free-enzyme form, thus suggesting that penicillin acylase was entrapped in its native state into aqueous free spaces of the polymer matrix.

  5. Radiation-induced degradation of 4-chloroaniline in aqueous solution

    NASA Astrophysics Data System (ADS)

    Sánchez, M.; Wolfger, H.; Getoff, N.

    2002-12-01

    The radiation-induced decomposition of 4-chloroaniline (4-ClA) was studied under steady-state conditions using aqueous solutions saturated with air, pure oxygen, N 2O, argon and argon in the presence of t-Butanol. Using HPLC-method, the initial G-values of the substrate degradation as well as of a number of radiolytic products were determined. The formation of aminophenols, chlorophenols, aniline and phenol in addition to chloride, ammonia, formaldehyde and mixture of aldehydes as well as carboxylic acids was studied as a function of absorbed dose. Based on the experimental data, probable reaction mechanisms for the degradation of 4-ClA by γ-rays and the formation of the identified products are presented.

  6. Pulsed radiation-induced attenuation in certain optical fibers

    SciTech Connect

    Weiss, J.D. )

    1992-05-01

    Using the X-ray pulse from the HERMES II simulation machine at Sandia National Laboratories, the pulsed radiation-induced attenuation was measured in two optical fibers considered to be 'nonrad-hard': the 50-micron-core, graded-index fiber from Corning and the plastic (PMMA) fiber from the Mitsubishi Rayon Company. These fibers were exposed to radiation up to doses of 19.5 and 28 krad(Si), respectively. In addition, fits of their post-radiation recovery were made to the geminate recombination model, from which the recombination-rate and generation constants, characteristic of this theory, were determined. These parameters should be useful in determining the response of the fibers to radiation conditions other than those encountered here. 18 refs.

  7. Modification of microcrystalline cellulose by gamma radiation-induced grafting

    NASA Astrophysics Data System (ADS)

    Madrid, Jordan F.; Abad, Lucille V.

    2015-10-01

    Modified microcrystalline cellulose (MCC) was prepared through gamma radiation-induced graft polymerization of glycidyl methacrylate (GMA). Simultaneous grafting was employed wherein MCC with GMA in methanol was irradiated with gamma radiation in nitrogen atmosphere. The effects of different experimental factors such as monomer concentration, type of solvent and absorbed dose on the degree of grafting, Dg, were studied. The amount of grafted GMA, expressed as Dg, was determined gravimetrically. Information from grafted samples subjected to Fourier transformed infrared spectroscopy (FTIR) in attenuated total reflectance (ATR) mode showed peaks corresponding to GMA which indicates successful grafting. The X-ray diffraction (XRD) analysis revealed that the crystalline region of MCC was not adversely affected after grafting with GMA. The thermogravimetric analysis (TGA) data showed that the decomposition of grafted MCC occurred at higher temperature compared to the base MCC polymer.

  8. Radiation-induced cerebral meningioma: a recognizable entity.

    PubMed

    Rubinstein, A B; Shalit, M N; Cohen, M L; Zandbank, U; Reichenthal, E

    1984-11-01

    The authors retrospectively analyzed the clinical and histopathological findings in 201 patients with intracranial meningiomas operated on in the period 1978 to 1982. Forty-three of the patients (21.4%) had at some previous time received radiation treatment to their scalp, the majority for tinea capitis. The findings in these 43 irradiated patients were compared with those in the 158 non-irradiated patients. Several distinctive clinical and histological features were identified in the irradiated group, which suggest that radiation-induced meningiomas can be defined as a separate nosological subgroup. The use of irradiation in large numbers of children with tinea capitis in the era prior to the availability of griseofulvin may be responsible for a significantly increased incidence of intracranial meningiomas.

  9. Study of radiation induced cancers in a breast screening programme.

    PubMed

    León, A; Verdú, G; Cuevas, M D; Salas, M D; Villaescusa, J I; Bueno, F

    2001-01-01

    It is demonstrated that screening mammography programmes reduce breast cancer mortality considerably. Nevertheless, radiology techniques have an intrinsic risk, the most important being the late somatic effect of the induction of cancer. This study was carried out in order to evaluate the risk to the population produced by the Comunidad Valenciana Breast Screening Programme. All the calculations are carried out for two risk models, UNSCEAR 94 and NRPB 93. On the one hand, screening series detriments are investigated as a function of doses delivered and other parameters related to population structure and X ray equipment. On the other hand the radiation induced cancer probability for a woman who starts at 45 years and remains in the programme until 65 years old is calculated as a function of mammography units' doses and average compression breast thickness. Finally, risk comparison between a screening programme starting at 45 years old and another one starting at 50 years old is made.

  10. Radiation-induced cationic polymerization of. beta. -pinene

    SciTech Connect

    Adur, A.M.; Williams, F.

    1981-03-01

    The radiation-induced polymerization of ..beta..-pinene carried out in bulk at ca.25/sup 0/ has been studied for different methods of monomer drying. It has been confirmed that the polymerization is sensitive to adventitious moisture and that substantial polymer yields (ca. 10% conversion per Mrad) can only be obtained under extremely dry conditions. Complete inhibition of the reaction by added tripropylamine corroborates the view that the polymerization is cationic. About half of the polymer formed is insoluble in the monomer. The number-average molecular weights for the soluble poly(..beta..-pinene) fraction have been measured by vapor pressure osmometry and are in the narrow range from 1700 to 2400 with little or no dependence on the degree of monomer conversion to polymer, at least up to 80%. The results are compared with literature reports on the polymerization of ..beta..-pinene by catalytic initiators.

  11. Radiation Induced Cystitis and Proctitis - Prediction, Assessment and Management.

    PubMed

    Mallick, Supriya; Madan, Renu; Julka, Pramod K; Rath, Goura K

    2015-01-01

    Cystitis and proctitis are defined as inflammation of bladder and rectum respectively. Haemorrhagic cystitis is the most severe clinical manifestation of radiation and chemical cystitis. Radiation proctitis and cystitis are major complications following radiotherapy. Prevention of radiation-induced haemorrhagic cystitis has been investigated using various oral agents with minimal benefit. Bladder irrigation remains the most frequently adopted modality followed by intra-vesical instillation of alum or formalin. In intractable cases, surgical intervention is required in the form of diversion ureterostomy or cystectomy. Proctitis is more common in even low dose ranges but is self-limiting and improves on treatment interruption. However, treatment of radiation proctitis is broadly non-invasive or invasive. Non-invasive treatment consists of non-steroid anti-inflammatory drugs (NSAIDs), anti-oxidants, sucralfate, short chain fatty acids and hyperbaric oxygen. Invasive treatment consists of ablative procedures like formalin application, endoscopic YAG laser coagulation or argon plasma coagulation and surgery as a last resort.

  12. Probabilistic methodology for estimating radiation-induced cancer risk

    SciTech Connect

    Dunning, D.E. Jr.; Leggett, R.W.; Williams, L.R.

    1981-01-01

    The RICRAC computer code was developed at Oak Ridge National Laboratory to provide a versatile and convenient methodology for radiation risk assessment. The code allows as input essentially any dose pattern commonly encountered in risk assessments for either acute or chronic exposures, and it includes consideration of the age structure of the exposed population. Results produced by the analysis include the probability of one or more radiation-induced cancer deaths in a specified population, expected numbers of deaths, and expected years of life lost as a result of premature fatalities. These calculatons include consideration of competing risks of death from all other causes. The program also generates a probability frequency distribution of the expected number of cancers in any specified cohort resulting from a given radiation dose. The methods may be applied to any specified population and dose scenario.

  13. Radiatively induced breaking of conformal symmetry in a superpotential

    NASA Astrophysics Data System (ADS)

    Arbuzov, A. B.; Cirilo-Lombardo, D. J.

    2016-07-01

    Radiatively induced symmetry breaking is considered for a toy model with one scalar and one fermion field unified in a superfield. It is shown that the classical quartic self-interaction of the superfield possesses a quantum infrared singularity. Application of the Coleman-Weinberg mechanism for effective potential leads to the appearance of condensates and masses for both scalar and fermion components. That induces a spontaneous breaking of the initial classical symmetries: the supersymmetry and the conformal one. The energy scales for the scalar and fermion condensates appear to be of the same order, while the renormalization scale is many orders of magnitude higher. A possibility to relate the considered toy model to conformal symmetry breaking in the Standard Model is discussed.

  14. Modulation of radiation-induced hemopoietic suppression by acute thrombocytopenia

    SciTech Connect

    Ebbe, S.; Phalen, E.; Threatte, G.; Londe, H.

    1985-01-01

    Modifications of radiation-induced hemopoietic suppression by acute thrombocytopenia were evaluated. Immediately before or after exposure to sublethal irradiation, mice were given a single injection of anti-mouse platelet serum (APS), normal heterologous serum, neuraminidase (N'ase), or saline, or no further treatment was provided. Hemopoiesis was evaluated by blood cell counts, hematocrits, and incorporation of (75Se)selenomethionine into platelets. APS and N'ase induced an acute thrombocytopenia from which there was partial recovery before the platelet count started to fall from the radiation. During the second post-treatment week, both thrombocytopoiesis and erythropoiesis were greater in mice that received APS or N'ase in addition to radiation than in control irradiated mice. Differences in leukopoiesis were not apparent. Therefore, both thrombocytopoiesis and erythropoiesis appeared to be responsive to a stimulus generated by acute thrombocytopenia in sublethally irradiated mice.

  15. Bystander effects in radiation-induced genomic instability

    NASA Technical Reports Server (NTRS)

    Morgan, William F.; Hartmann, Andreas; Limoli, Charles L.; Nagar, Shruti; Ponnaiya, Brian

    2002-01-01

    Exposure of GM10115 hamster-human hybrid cells to X-rays can result in the induction of chromosomal instability in the progeny of surviving cells. This instability manifests as the dynamic production of novel sub-populations of cells with unique cytogenetic rearrangements involving the "marker" human chromosome. We have used the comet assay to investigate whether there was an elevated level of endogenous DNA breaks in chromosomally unstable clones that could provide a source for the chromosomal rearrangements and thus account for the persistent instability observed. Our results indicate no significant difference in comet tail measurement between non-irradiated and radiation-induced chromosomally unstable clones. Using two-color fluorescence in situ hybridization we also investigated whether recombinational events involving the interstitial telomere repeat-like sequences in GM10115 cells were involved at frequencies higher than random processes would otherwise predict. Nine of 11 clones demonstrated a significantly higher than expected involvement of these interstitial telomere repeat-like sequences at the recombination junction between the human and hamster chromosomes. Since elevated levels of endogenous breaks were not detected in unstable clones we propose that epigenetic or bystander effects (BSEs) lead to the activation of recombinational pathways that perpetuate the unstable phenotype. Specifically, we expand upon the hypothesis that radiation induces conditions and/or factors that stimulate the production of reactive oxygen species (ROS). These reactive intermediates then contribute to a chronic pro-oxidant environment that cycles over multiple generations, promoting chromosomal recombination and other phenotypes associated with genomic instability.

  16. Radiation-induced fibrosis: mechanisms and implications for therapy

    PubMed Central

    Straub, Jeffrey M.; New, Jacob; Hamilton, Chase D.; Lominska, Chris; Shnayder, Yelizaveta

    2015-01-01

    Purpose Radiation-induced fibrosis (RIF) is a long-term side effect of external beam radiation therapy for the treatment of cancer. It results in a multitude of symptoms that significantly impact quality of life. Understanding the mechanisms of RIF-induced changes is essential to developing effective strategies to prevent long-term disability and discomfort following radiation therapy. In this review, we describe the current understanding of the etiology, clinical presentation, pathogenesis, treatment, and directions of future therapy for this condition. Methods A literature review of publications describing mechanisms or treatments of RIF was performed. Specific databases utilized included PubMed and clinicaltrials.gov, using keywords “Radiation-Induced Fibrosis,” “Radiotherapy Complications,” “Fibrosis Therapy,” and other closely related terms. Results RIF is the result of a misguided wound healing response. In addition to causing direct DNA damage, ionizing radiation generates reactive oxygen and nitrogen species that lead to localized inflammation. This inflammatory process ultimately evolves into a fibrotic one characterized by increased collagen deposition, poor vascularity, and scarring. Tumor growth factor beta serves as the primary mediator in this response along with a host of other cytokines and growth factors. Current therapies have largely been directed toward these molecular targets and their associated signaling pathways. Conclusion Although RIF is widely prevalent among patients undergoing radiation therapy and significantly impacts quality of life, there is still much to learn about its pathogenesis and mechanisms. Current treatments have stemmed from this understanding, and it is anticipated that further elucidation will be essential for the development of more effective therapies. PMID:25910988

  17. Ion beam induced luminescence: Relevance to radiation induced bystander effects

    NASA Astrophysics Data System (ADS)

    Ahmad, S. B.; McNeill, F. E.; Byun, S. H.; Prestwich, W. V.; Seymour, C.; Mothersill, C. E.

    2012-10-01

    The aim of this work is quantify the light emitted as a result of charged particle interaction in materials which may be of relevance to radiation induced "bystander effects" studies. We have developed a system which employs single photon counting to measure the light emitted from samples irradiated under vacuum by a charged particle beam. The system uses a fast photomultiplier tube with a peak cathode response at 420 nm. It has been tested in a proof-of-principle experiment using polystyrene targets. Light output, as a result of irradiation, was measured. The luminescence yield appears to have a non-linear behavior with the incident ion fluence: it rises exponentially to an asymptotic value. The target was irradiated with beam energies varying from 1 to 2 MeV and showed saturation at or before an incident fluence rate of 3 × 1013 H+/cm2 s. The average saturation value for the photon output was found to be 40 × 106 cps. Some measurements were performed using filters to study the emission at specific wavelengths. In the case of filtered light measurements, the photon output was found to saturate at 28 × 103, 10 × 106, and 35 × 106 cps for wavelengths of 280 ± 5 nm, 320 ± 5 nm and 340 ± 5 nm respectively. The light output reaches a maximum value because of damage induced in the polymer. Our measurements indicate a "damage cross section" of the order of 10-14 cm2. The average radiant intensity was found to increase at wavelengths of 280 and 320 nm when the proton energy was increased. This was not found to occur at 340 nm. In conclusion, the light emission at specific wavelengths was found to depend upon the incident proton fluence and the proton energy. The wavelengths of the emitted light measured in this study have significance for the understanding of radiation induced bystander effects.

  18. Barriers to Radiation-Induced In Situ Tumor Vaccination

    PubMed Central

    Wennerberg, Erik; Lhuillier, Claire; Vanpouille-Box, Claire; Pilones, Karsten A.; García-Martínez, Elena; Rudqvist, Nils-Petter; Formenti, Silvia C.; Demaria, Sandra

    2017-01-01

    The immunostimulatory properties of radiation therapy (RT) have recently generated widespread interest due to preclinical and clinical evidence that tumor-localized RT can sometimes induce antitumor immune responses mediating regression of non-irradiated metastases (abscopal effect). The ability of RT to activate antitumor T cells explains the synergy of RT with immune checkpoint inhibitors, which has been well documented in mouse tumor models and is supported by observations of more frequent abscopal responses in patients refractory to immunotherapy who receive RT during immunotherapy. However, abscopal responses following RT remain relatively rare in the clinic, and antitumor immune responses are not effectively induced by RT against poorly immunogenic mouse tumors. This suggests that in order to improve the pro-immunogenic effects of RT, it is necessary to identify and overcome the barriers that pre-exist and/or are induced by RT in the tumor microenvironment. On the one hand, RT induces an immunogenic death of cancer cells associated with release of powerful danger signals that are essential to recruit and activate dendritic cells (DCs) and initiate antitumor immune responses. On the other hand, RT can promote the generation of immunosuppressive mediators that hinder DCs activation and impair the function of effector T cells. In this review, we discuss current evidence that several inhibitory pathways are induced and modulated in irradiated tumors. In particular, we will focus on factors that regulate and limit radiation-induced immunogenicity and emphasize current research on actionable targets that could increase the effectiveness of radiation-induced in situ tumor vaccination. PMID:28348554

  19. Role of Oxidative Damage in Radiation-Induced Bone Loss

    NASA Technical Reports Server (NTRS)

    Schreurs, Ann-Sofie; Alwood, Joshua S.; Limoli, Charles L.; Globus, Ruth K.

    2014-01-01

    used an array of countermeasures (Antioxidant diets and injections) to prevent the radiation-induced bone loss, although these did not prevent bone loss, analysis is ongoing to determine if these countermeasure protected radiation-induced damage to other tissues.

  20. Radiation-induced leukemia: Comparative studies in mouse and man

    SciTech Connect

    Haas, M.

    1991-01-01

    We now have a clear understanding of the mechanism by which radiation-induced (T-cell) leukemia occurs. In irradiated mice (radiation-induced thymic leukemia) and in man (acute lymphoblastic T-cell leukemia, T-ALL) the mechanism of leukemogenesis is surprisingly similar. Expressed in the most elementary terms, T-cell leukemia occurs when T-cell differentiation is inhibited by a mutation, and pre-T cells attempt but fail to differentiate in the thymus. Instead of leaving the thymus for the periphery as functional T-cells they continue to proliferate in the thymus. The proliferating pre- (pro-) T-cells constitute the (early) acute T-cell leukemia (A-TCL). This model for the mechanism of T-cell leukemogenesis accounts for all the properties of both murine and human A-TCL. Important support for the model has recently come from work by Ilan Kirsch and others, who have shown that mutations/deletions in the genes SCL (TAL), SIL, and LCK constitute primary events in the development of T-ALL, by inhibiting differentiation of thymic pre- (pro-) T-cells. This mechanism of T-cell leukemogenesis brings several specific questions into focus: How do early A-TCL cells progress to become potently tumorigenic and poorly treatable Is it feasible to genetically suppress early and/or progressed A-TCL cells What is the mechanism by which the differentiation-inhibited (leukemic) pre-T cells proliferate During the first grant year we have worked on aspects of all three questions.

  1. Radiation-induced sarcomas of bone: factors that affect outcome.

    PubMed

    Kalra, S; Grimer, R J; Spooner, D; Carter, S R; Tillman, R M; Abudu, A

    2007-06-01

    We identified 42 patients who presented to our unit over a 27-year period with a secondary radiation-induced sarcoma of bone. We reviewed patient, tumour and treatment factors to identify those that affected outcome. The mean age of the patients at presentation was 45.6 years (10 to 84) and the mean latent interval between radiotherapy and diagnosis of the sarcoma was 17 years (4 to 50). The median dose of radiotherapy given was estimated at 50 Gy (mean 49; 20 to 66). There was no correlation between radiation dose and the time to development of a sarcoma. The pelvis was the most commonly affected site (14 patients (33%)). Breast cancer was the most common primary tumour (eight patients; 19%). Metastases were present at diagnosis of the sarcoma in nine patients (21.4%). Osteosarcoma was the most common diagnosis and occurred in 30 cases (71.4%). Treatment was by surgery and chemotherapy when indicated: 30 patients (71.4%) were treated with the intention to cure. The survival rate was 41% at five years for those treated with the intention to cure but in those treated palliatively the mean survival was only 8.8 months (2 to 22), and all had died by two years. The only factor found to be significant for survival was the ability to completely resect the tumour. Limb sarcomas had a better prognosis (66% survival at five years) than central ones (12% survival at five years) (p = 0.009). Radiation-induced sarcoma is a rare complication of radiotherapy. Both surgical and oncological treatment is likely to be compromised by the treatment received previously by the patient.

  2. Intercellular Adhesion Molecule 1 Knockout Abrogates Radiation Induced Pulmonary Inflammation

    NASA Astrophysics Data System (ADS)

    Hallahan, Dennis E.; Virudachalam, Subbulakshmi

    1997-06-01

    Increased expression of intercellular adhesion molecule 1 (ICAM-1; CD54) is induced by exposure to ionizing radiation. The lung was used as a model to study the role of ICAM-1 in the pathogenesis of the radiation-induced inflammation-like response. ICAM-1 expression increased in the pulmonary microvascular endothelium and not in the endothelium of larger pulmonary vessels following treatment of mice with thoracic irradiation. To quantify radiation-induced ICAM-1 expression, we utilized fluorescence-activated cell sorting analysis of anti-ICAM-1 antibody labeling of pulmonary microvascular endothelial cells from human cadaver donors (HMVEC-L cells). Fluorochrome conjugates and UV microscopy were used to quantify the fluorescence intensity of ICAM in the irradiated lung. These studies showed a dose- and time-dependent increase in ICAM-1 expression in the pulmonary microvascular endothelium. Peak expression occurred at 24 h, while threshold dose was as low as 2 Gy. To determine whether ICAM-1 is required for inflammatory cell infiltration into the irradiated lung, the anti-ICAM-1 blocking antibody was administered by tail vein injection to mice following thoracic irradiation. Inflammatory cells were quantified by immunofluorescence for leukocyte common antigen (CD45). Mice treated with the anti-ICAM-1 blocking antibody showed attenuation of inflammatory cell infiltration into the lung in response to ionizing radiation exposure. To verify the requirement of ICAM-1 in the inflammation-like radiation response, we utilized the ICAM-1 knockout mouse. ICAM-1 was not expressed in the lungs of ICAM-1-deficient mice following treatment with thoracic irradiation. ICAM-1 knockout mice had no increase in the inflammatory cell infiltration into the lung in response to thoracic irradiation. These studies demonstrate a radiation dose-dependent increase in ICAM-1 expression in the pulmonary microvascular endothelium, and show that ICAM-1 is required for inflammatory cell infiltration

  3. Evidence for Radiation-Induced Disseminated Intravascular Coagulation as a Major Cause of Radiation-Induced Death in Ferrets

    PubMed Central

    Krigsfeld, Gabriel S.; Savage, Alexandria R.; Billings, Paul C.; Lin, Liyong; Kennedy, Ann R.

    2014-01-01

    Purpose/Objectives(s) The studies reported here were performed as part of a program in space radiation biology in which proton radiation like that present in solar particle events (SPEs), as well as conventional gamma radiation, were being evaluated in terms of the ability to affect hemostasis. Methods and Materials Ferrets were exposed to 0 – 2 Gray (Gy) of whole body proton or gamma radiation and monitored for 30 days. Blood was analyzed for blood cell counts, platelet clumping, thromboelastometry, and fibrin clot formation. Results The lethal dose of radiation to 50% of the population, known as the LD50, of ferrets was established at ~ 1.5 Gy, with 100% mortality at 2 Gy. Hypocoagulability was present as early as day 7 post-irradiation, with animals unable to generate a stable clot and exhibiting signs of platelet aggregation, thrombocytopenia, and fibrin clots in blood vessels of organs. Platelet counts were at normal levels during the early times post-irradiation when coagulopathies were present and progressively becoming more severe; platelet counts were greatly reduced at the time of the white blood cell nadir of 13 days. Conclusions The data presented here provide evidence that death at the LD50 in ferrets is most likely due to disseminated intravascular coagulation (DIC). These data question the current hypothesis that death at relatively low doses of radiation is solely due to the cell killing effects of hematopoietic cells. The recognition that radiation-induced DIC is the most likely mechanism of death in ferrets raises the question of whether DIC is a contributing mechanism to radiation induced death at relatively low doses in large mammals. PMID:24495588

  4. Evidence for Radiation-Induced Disseminated Intravascular Coagulation as a Major Cause of Radiation-Induced Death in Ferrets

    SciTech Connect

    Krigsfeld, Gabriel S.; Savage, Alexandria R.; Billings, Paul C.; Lin, Liyong; Kennedy, Ann R.

    2014-03-15

    Purpose: The studies reported here were performed as part of a program in space radiation biology in which proton radiation like that present in solar particle events, as well as conventional gamma radiation, were being evaluated in terms of the ability to affect hemostasis. Methods and Materials: Ferrets were exposed to 0 to 2 Gy of whole-body proton or gamma radiation and monitored for 30 days. Blood was analyzed for blood cell counts, platelet clumping, thromboelastometry, and fibrin clot formation. Results: The lethal dose of radiation to 50% of the population (LD{sub 50}) of the ferrets was established at ∼1.5 Gy, with 100% mortality at 2 Gy. Hypocoagulability was present as early as day 7 postirradiation, with animals unable to generate a stable clot and exhibiting signs of platelet aggregation, thrombocytopenia, and fibrin clots in blood vessels of organs. Platelet counts were at normal levels during the early time points postirradiation when coagulopathies were present and becoming progressively more severe; platelet counts were greatly reduced at the time of the white blood cell nadir of 13 days. Conclusions: Data presented here provide evidence that death at the LD{sub 50} in ferrets is most likely due to disseminated intravascular coagulation (DIC). These data question the current hypothesis that death at relatively low doses of radiation is due solely to the cell-killing effects of hematopoietic cells. The recognition that radiation-induced DIC is the most likely mechanism of death in ferrets raises the question of whether DIC is a contributing mechanism to radiation-induced death at relatively low doses in large mammals.

  5. Involvement of prostaglandins and histamine in radiation-induced temperature responses in rats

    SciTech Connect

    Kandasamy, S.B.; Hunt, W.A. )

    1990-01-01

    Exposure of rats to 1-15 Gy of gamma radiation induced hyperthermia, whereas exposure to 20-150 Gy produced hypothermia. Since radiation exposure induced the release of prostaglandins (PGs) and histamine, the role of PGs and histamine in radiation-induced temperature changes was examined. Radiation-induced hyper- and hypothermia were antagonized by pretreatment with indomethacin, a cyclooxygenase inhibitor. Intracerebroventricular administration of PGE2 and PGD2 induced hyper- and hypothermia, respectively. Administration of SC-19220, a specific PGE2 antagonist, attenuated PGE2- and radiation-induced hyperthermia, but it did not antagonize PGD2- or radiation-induced hypothermia. Consistent with an apparent role of histamine in hypothermia, administration of disodium cromoglycate (a mast cell stabilizer), mepyramine (H1-receptor antagonist), or cimetidine (H2-receptor antagonist) attenuated PGD2- and radiation-induced hypothermia. These results suggest that radiation-induced hyperthermia is mediated via PGE2 and that radiation-induced hypothermia is mediated by another PG, possibly PGD2, via histamine.

  6. Countermeasures for Space Radiation Induced Malignancies and Acute Biological Effects

    NASA Astrophysics Data System (ADS)

    Kennedy, Ann

    The hypothesis being evaluated in this research program is that control of radiation induced oxidative stress will reduce the risk of radiation induced adverse biological effects occurring as a result of exposure to the types of radiation encountered during space travel. As part of this grant work, we have evaluated the protective effects of several antioxidants and dietary supplements and observed that a mixture of antioxidants (AOX), containing L-selenomethionine, N-acetyl cysteine (NAC), ascorbic acid, vitamin E succinate, and alpha-lipoic acid, is highly effective at reducing space radiation induced oxidative stress in both in vivo and in vitro systems, space radiation induced cytotoxicity and malignant transformation in vitro [1-7]. In studies designed to determine whether the AOX formulation could affect radiation induced mortality [8], it was observed that the AOX dietary supplement increased the 30-day survival of ICR male mice following exposure to a potentially lethal dose (8 Gy) of X-rays when given prior to or after animal irradiation. Pretreatment of animals with antioxidants resulted in significantly higher total white blood cell and neutrophil counts in peripheral blood at 4 and 24 hours following exposure to doses of 1 Gy and 8 Gy. Antioxidant treatment also resulted in increased bone marrow cell counts following irradiation, and prevented peripheral lymphopenia following 1 Gy irradiation. Supplementation with antioxidants in irradiated animals resulted in several gene expression changes: the antioxidant treatment was associated with increased Bcl-2, and decreased Bax, caspase-9 and TGF-β1 mRNA expression in the bone marrow following irradiation. These results suggest that modulation of apoptosis may be mechanistically involved in hematopoietic system radioprotection by antioxidants. Maintenance of the antioxidant diet was associated with improved recovery of the bone marrow following sub-lethal or potentially lethal irradiation. Taken together

  7. Automated analysis of brachial ultrasound time series

    NASA Astrophysics Data System (ADS)

    Liang, Weidong; Browning, Roger L.; Lauer, Ronald M.; Sonka, Milan

    1998-07-01

    Atherosclerosis begins in childhood with the accumulation of lipid in the intima of arteries to form fatty streaks, advances through adult life when occlusive vascular disease may result in coronary heart disease, stroke and peripheral vascular disease. Non-invasive B-mode ultrasound has been found useful in studying risk factors in the symptom-free population. Large amount of data is acquired from continuous imaging of the vessels in a large study population. A high quality brachial vessel diameter measurement method is necessary such that accurate diameters can be measured consistently in all frames in a sequence, across different observers. Though human expert has the advantage over automated computer methods in recognizing noise during diameter measurement, manual measurement suffers from inter- and intra-observer variability. It is also time-consuming. An automated measurement method is presented in this paper which utilizes quality assurance approaches to adapt to specific image features, to recognize and minimize the noise effect. Experimental results showed the method's potential for clinical usage in the epidemiological studies.

  8. The effect of tianeptine in the prevention of radiation-induced neurocognitive impairment.

    PubMed

    Akyurek, Serap; Senturk, Vesile; Oncu, Bedriye; Ozyigit, Gokhan; Yilmaz, Sercan; Gokce, Saban Cakir

    2008-12-01

    Radiation-induced neurocognitive impairment is an undesirable radiation-induced toxicity and a common health problem in patients with primary or metastatic brain tumor. It greatly impairs quality of life for long-term brain tumor survivors. Hippocampus is the most important brain structure for neurocognitive functions. It has been shown that radiation affects the hippocampal neurogenesis due to either induce the apoptosis or reduce the precursor cell proliferation in the hippocampus. Radiation-induced microglial inflammatory response is also negative regulator of neurogenesis. Tianeptine is a clinically effective antidepressant that induces neurogenesis. It has also been shown that tianeptine is able to reduce apoptosis and cytoprotective against the effects of proinflammatory cytokines in the hippocampus. Given the putative role of impaired hippocampal neurogenesis in radiation-induced neurocognitive impairment we think that tianeptine can be effective for preventing radiation-induced neurocognitive impairment by increasing hippocampal neurogenesis.

  9. Morphology of brachial plexus and axillary artery in bonobo (Pan paniscus).

    PubMed

    Kikuchi, Y; Oishi, M; Shimizu, D

    2011-02-01

    A left brachial plexus and axillary artery of bonobo (Pan paniscus) were examined, and the interrelation between the brachial plexus and the axillary artery was discussed. This is the first report of the brachial plexus and the axillary artery of bonobo. The bonobo brachial plexus formed very similar pattern to that of other ape species and human. On the other hand, the branches of the bonobo axillary artery had uncommon architecture in comparison with human case. The axillary artery did not penetrate the brachial plexus and passes through all way along anterior to the brachial plexus. Only 4.9% of human forelimbs have this pattern. Moreover, the brachial artery runs through superficially anterior to branches of the brachial plexus.

  10. Space-radiation-induced Photon Luminescence of the Moon

    NASA Technical Reports Server (NTRS)

    Wilson, Thomas; Lee, Kerry

    2008-01-01

    We report on the results of a study of the photon luminescence of the Moon induced by Galactic Cosmic Rays (GCRs) and space radiation from the Sun, using the Monte Carlo program FLUKA. The model of the lunar surface is taken to be the chemical composition of soils found at various landing sites during the Apollo and Luna programs, averaged over all such sites to define a generic regolith for the present analysis. This then becomes the target that is bombarded by Galactic Cosmic Rays (GCRs) and Solar Energetic Particles (SEPs) above 1 keV in FLUKA to determine the photon fluence albedo produced by the Moon's surface when there is no sunlight and Earthshine. This is to be distinguished from the gamma-ray spectrum produced by the radioactive decay of radiogenic constituents lying in the surface and interior of the Moon. From the photon fluence we derive the spectrum which can be utilized to examine existing lunar spectral data and to design orbiting instrumentation for measuring various components of the space-radiation-induced photon luminescence present on the Moon.

  11. Gamma radiation induces hydrogen absorption by copper in water

    PubMed Central

    Lousada, Cláudio M.; Soroka, Inna L.; Yagodzinskyy, Yuriy; Tarakina, Nadezda V.; Todoshchenko, Olga; Hänninen, Hannu; Korzhavyi, Pavel A.; Jonsson, Mats

    2016-01-01

    One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories. PMID:27086752

  12. Outcome of Carotid Artery Stenting for Radiation-Induced Stenosis

    SciTech Connect

    Dorresteijn, Lucille; Vogels, Oscar; Leeuw, Frank-Erik de; Vos, Jan-Albert; Christiaans, Marleen H.; Ackerstaff, Rob; Kappelle, Arnoud C.

    2010-08-01

    Purpose: Patients who have been irradiated at the neck have an increased risk of symptomatic stenosis of the carotid artery during follow-up. Carotid angioplasty and stenting (CAS) can be a preferable alternative treatment to carotid endarterectomy, which is associated with increased operative risks in these patients. Methods and Materials: We performed a prospective cohort study of 24 previously irradiated patients who underwent CAS for symptomatic carotid stenosis. We assessed periprocedural and nonprocedural events including transient ischemic attack (TIA), nondisabling stroke, disabling stoke, and death. Patency rates were evaluated on duplex ultrasound scans. Restenosis was defined as a stenosis of >50% at the stent location. Results: Periprocedural TIA rate was 8%, and periprocedural stroke (nondisabling) occurred in 4% of patients. After a mean follow-up of 3.3 years (range, 0.3-11.0 years), only one ipsilateral incident event (TIA) had occurred (4%). In 12% of patients, a contralateral incident event was present: one TIA (4%) and two strokes (12%, two disabling strokes). Restenosis was apparent in 17%, 33%, and 42% at 3, 12, and 24 months, respectively, although none of the patients with restenosed vessels became symptomatic. The length of the irradiation to CAS interval proved the only significant risk factor for restenosis. Conclusions: The results of CAS for radiation-induced carotid stenosis are favorable in terms of recurrence of cerebrovascular events at the CAS site.

  13. Radiation-induced thymine base damage in replicating chromatin

    SciTech Connect

    Warters, R.L.; Childers, T.J.

    1982-06-01

    The efficiency of radiation-induced production of 5',6'-dihydroxydihydrothymine (t/sup ..gamma../)-type damage was determined in nascent and mature chromatin DNA for the dose range of 50 to 150 krad. These large doses affected neither the total fraction of nuclear DNA in chromatin subunits nor the nucleosome subunit repeat length. The DNA in nascent chromatin, however, was found to be 3.3 times more sensitive than mature chromatin DNA to ..gamma..-ray (/sup 137/Cs)-induced t/sup ..gamma../-type damage, while thymine damage of this type was uniformly distributed in the nucleosomal DNA of mature chromatin (i.e., in the nucleosome core and spacer DNA). The half-time for the transition of nascent DNA sensitivity to mature chromatin DNA sensitivity levels was the same as the half-time at 37/sup 0/C for the maturation of nascent into mature chromatin structure. The rate at which nascent chromatin matured was unaffected by radiation doses as large as 150 krad. The most logical explanation for the greater sensitivity of nascent DNA to radiation is the decreased concentration of histone chromosomal proteins in nascent chromatin.

  14. Radiation induced degradation of dyes--an overview.

    PubMed

    Rauf, M A; Ashraf, S Salman

    2009-07-15

    Synthetic dyes are a major part of our life. Products ranging from clothes to leather accessories to furniture all depend on extensive use of organic dyes. An unfortunate side effect of extensive use of these chemicals is that huge amounts of these potentially carcinogenic compounds enter our water supplies. Various advanced oxidation processes (AOPs) including the use of high-energy radiation have been developed to degrade these compounds. In this review, dye decoloration and degradation as a result of its exposure to high energy radiation such as gamma radiation and pulsed electron beam are discussed in detail. The role of various transient species such as H, OH and e(aq)(-) are taken into account as reported by various researchers. Literature citations in this area show that e(aq)(-) is very effective in decolorization but is less active in the further degradation of the products formed. The degradation of the dyes is initiated exclusively by OH attack on electron-rich sites of the dye molecules. Additionally, various parameters that affect the efficiency of radiation induced degradation of dyes, such as effect of radiation dose, oxygen, pH, hydrogen peroxide, added ions and dye classes are also reviewed and summarized. Lastly, pilot plant application of radiation for wastewater treatment is briefly discussed.

  15. Gamma radiation induces hydrogen absorption by copper in water.

    PubMed

    Lousada, Cláudio M; Soroka, Inna L; Yagodzinskyy, Yuriy; Tarakina, Nadezda V; Todoshchenko, Olga; Hänninen, Hannu; Korzhavyi, Pavel A; Jonsson, Mats

    2016-04-18

    One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories.

  16. Early corticosteroid administration in experimental radiation-induced heart disease

    SciTech Connect

    Reeves, W.C.; Stryker, J.A.; Abt, A.A.; Chung, C.K.; Whitesell, L.; Zelis, R.

    1980-02-01

    The ability of dexamethasone (DEX) to reduce the severity of the late stage of radiation-induced heart disease (RIHD) was assessed in 25 New Zealand white rabbits. Ten rabbits served as unirradiated controls (CONT). In Group A, seven rabbits received intravenous DEX prior to irradiation and every 24 hours for three consecutive days. DEX was not administered to the eight rabbits in Group B. At 100 days postirradiation, the severity of the late state was determined by microscopic examination (MICRO) for myocardial fibrosis and determination of myocardial hydroxyproline content (MHP). Myocardial fibrosis was evident in groups A (40%) and B (80%) while none was present in CONT by MICRO. One rabbit in Group B with no fibrosis by MICRO had abnormally increased MHP. MHP was significantly increased in Groups A and B, as compared to CONT (p < 0.01). In addition to less fibrosis by MICRO, Group A demonstrated a significant reduction of MHP when compared to Group B (p < 0.05). Determination of MHP may be superior to MICRO in the detection of the late stage of RIHD. Also, early DEX administration appears to reduce myocardial collagen content (fibrosis) in this experimental model.

  17. Epigenetic determinants of space radiation-induced cognitive dysfunction

    PubMed Central

    Acharya, Munjal M.; Baddour, Al Anoud D.; Kawashita, Takumi; Allen, Barrett D.; Syage, Amber R.; Nguyen, Thuan H.; Yoon, Nicole; Giedzinski, Erich; Yu, Liping; Parihar, Vipan K.; Baulch, Janet E.

    2017-01-01

    Among the dangers to astronauts engaging in deep space missions such as a Mars expedition is exposure to radiations that put them at risk for severe cognitive dysfunction. These radiation-induced cognitive impairments are accompanied by functional and structural changes including oxidative stress, neuroinflammation, and degradation of neuronal architecture. The molecular mechanisms that dictate CNS function are multifaceted and it is unclear how irradiation induces persistent alterations in the brain. Among those determinants of cognitive function are neuroepigenetic mechanisms that translate radiation responses into altered gene expression and cellular phenotype. In this study, we have demonstrated a correlation between epigenetic aberrations and adverse effects of space relevant irradiation on cognition. In cognitively impaired irradiated mice we observed increased 5-methylcytosine and 5-hydroxymethylcytosine levels in the hippocampus that coincided with increased levels of the DNA methylating enzymes DNMT3a, TET1 and TET3. By inhibiting methylation using 5-iodotubercidin, we demonstrated amelioration of the epigenetic effects of irradiation. In addition to protecting against those molecular effects of irradiation, 5-iodotubercidin restored behavioral performance to that of unirradiated animals. The findings of this study establish the possibility that neuroepigenetic mechanisms significantly contribute to the functional and structural changes that affect the irradiated brain and cognition. PMID:28220892

  18. Progesterone prevents radiation-induced apoptosis in breast cancer cells.

    PubMed

    Vares, Guillaume; Ory, Katherine; Lectard, Bruno; Levalois, Céline; Altmeyer-Morel, Sandrine; Chevillard, Sylvie; Lebeau, Jérôme

    2004-06-03

    Sex steroid hormones play an essential role in the control of homeostasis in the mammary gland. Although the involvement of progesterone in cellular proliferation and differentiation is well established, its exact role in the control of cell death still remains unclear. As dysregulation of the apoptotic process plays an important role in the pathogenesis of breast cancer, we investigated the regulation of apoptosis by progesterone in various breast cancer cell lines. Our results show that progesterone treatment protects against radiation-induced apoptosis. This prevention appears to be mediated by the progesterone receptor and is unrelated to p53 status. There is also no correlation with the intrinsic hormonal effect on cell proliferation, as the presence of cells in a particular phase of the cell cycle. Surprisingly, progesterone partly allows bypassing of the irradiation-induced growth arrest in G(2)/M in PgR+ cells, leading to an increase in cell proliferation after irradiation. One consequence of this effect is a higher rate of chromosome damage in these proliferating progesterone-treated cells compared to what is observed in untreated irradiated cells. We propose that progesterone, by inhibiting apoptosis and promoting the proliferation of cells with DNA damage, potentially facilitates the emergence of genetic mutations that may play a role in malignant transformation.

  19. Low dose radiation-induced endothelial cell retraction.

    PubMed

    Kantak, S S; Diglio, C A; Onoda, J M

    1993-09-01

    We characterized in vitro the effects of gamma-radiation (12.5-100 cGy) on pulmonary microvascular endothelial cell (PMEC) morphology and F-actin organization. Cellular retraction was documented by phase-contrast microscopy and the organization of actin microfilaments was determined by immunofluorescence. Characterization included radiation dose effects, their temporal duration and reversibility of the effects. A dose-dependent relationship between the level of exposure (12.5-100 cGy) and the rate and extent of endothelial retraction was observed. Moreover, analysis of radiation-induced depolymerization of F-actin microfilament stress fibres correlated positively with the changes in PMEC morphology. The depolymerization of the stress fibre bundles was dependent on radiation dose and time. Cells recovered from exposure to reform contact inhibited monolayers > or = 24 h post-irradiation. Concomitantly, the depolymerized microfilaments reorganized to their preirradiated state as microfilament stress fibres arrayed parallel to the boundaries of adjacent contact-inhibited cells. The data presented here are representative of a series of studies designed to characterize low-dose radiation effects on pulmonary microvascular endothelium. Our data suggest that post-irradiation lung injuries (e.g. oedema) may be induced with only a single fraction of therapeutic radiation, and thus microscopic oedema may initiate prior to the lethal effects of radiation on the microvascular endothelium, and much earlier than would be suggested by the time course for clinically-detectable oedema.

  20. Radiation-induced sarcomas of the head and neck

    PubMed Central

    Thiagarajan, Anuradha; Iyer, N Gopalakrishna

    2014-01-01

    With improved outcomes associated with radiotherapy, radiation-induced sarcomas (RIS) are increasingly seen in long-term survivors of head and neck cancers, with an estimated risk of up to 0.3%. They exhibit no subsite predilection within the head and neck and can arise in any irradiated tissue of mesenchymal origin. Common histologic subtypes of RIS parallel their de novo counterparts and include osteosarcoma, chondrosarcoma, malignant fibrous histiocytoma/sarcoma nitricoxide synthase, and fibrosarcoma. While imaging features of RIS are not pathognomonic, large size, extensive local invasion with bony destruction, marked enhancement within a prior radiotherapy field, and an appropriate latency period are suggestive of a diagnosis of RIS. RIS development may be influenced by factors such as radiation dose, age at initial exposure, exposure to chemotherapeutic agents and genetic tendency. Precise pathogenetic mechanisms of RIS are poorly understood and both directly mutagenizing effects of radiotherapy as well as changes in microenvironments are thought to play a role. Management of RIS is challenging, entailing surgery in irradiated tissue and a limited scope for further radiotherapy and chemotherapy. RIS is associated with significantly poorer outcomes than stage-matched sarcomas that arise independent of irradiation and surgical resection with clear margins seems to offer the best chance for cure. PMID:25493233

  1. Nocifensive Behaviors in Mice with Radiation-Induced Oral Mucositis.

    PubMed

    Nolan, Michael W; Long, C Tyler; Marcus, Karen L; Sarmadi, Shayan; Roback, Donald M; Fukuyama, Tomoki; Baeumer, Wolfgang; Lascelles, B Duncan X

    2017-02-10

    Oral mucositis can result in significant dysphagia, and is the most common dose-limiting acute toxicity in head and neck cancer patients receiving chemoradiotherapy. There is a critical need to determine the cellular and molecular mechanisms that underlie radiotherapy-associated discomfort in patients with mucositis. The objective was to induce oral mucositis in mice, using a clinical linear accelerator, and to quantify resultant discomfort, and characterize peripheral sensitization. A clinical linear accelerator was used to deliver ionizing radiation to the oral cavity of mice. Mucositis severity scoring, and various behavioral assays were performed to quantify bouts of orofacial wiping and scratching, bite force, gnawing behavior and burrowing activity. Calcium imaging was performed on neurons of the trigeminal ganglia. Glossitis was induced with a single fraction of at least 27 Gy. Body weight decreased and subsequently returned to baseline, in concert with development and resolution of mucositis, which was worst at day 10 and 11 postirradiation, however was resolved within another 10 days. Neither bite force, nor gnawing behavior were measurably affected. However, burrowing activity was decreased, and both facial wiping and scratching were increased while mice had visible mucositis lesions. Sensory nerves of irradiated mice were more responsive to histamine, tumor necrosis factor alpha and capsaicin. Radiation-induced glossitis is associated with hyper-reactivity of sensory neurons in the trigeminal ganglia of mice, and is accompanied by several behaviors indicative of both itch and pain. These data validate an appropriate model for cancer treatment related discomfort in humans.

  2. Radiation-Induced Notch Signaling in Breast Cancer Stem Cells

    SciTech Connect

    Lagadec, Chann; Vlashi, Erina; Alhiyari, Yazeed; Phillips, Tiffany M.; Bochkur Dratver, Milana; Pajonk, Frank

    2013-11-01

    Purpose: To explore patterns of Notch receptor and ligand expression in response to radiation that could be crucial in defining optimal dosing schemes for γ-secretase inhibitors if combined with radiation. Methods and Materials: Using MCF-7 and T47D breast cancer cell lines, we used real-time reverse transcription–polymerase chain reaction to study the Notch pathway in response to radiation. Results: We show that Notch receptor and ligand expression during the first 48 hours after irradiation followed a complex radiation dose–dependent pattern and was most pronounced in mammospheres, enriched for breast cancer stem cells. Additionally, radiation activated the Notch pathway. Treatment with a γ-secretase inhibitor prevented radiation-induced Notch family gene expression and led to a significant reduction in the size of the breast cancer stem cell pool. Conclusions: Our results indicate that, if combined with radiation, γ-secretase inhibitors may prevent up-regulation of Notch receptor and ligand family members and thus reduce the number of surviving breast cancer stem cells.

  3. Radiation-induced heart disease in lung cancer radiotherapy

    PubMed Central

    Ming, Xin; Feng, Yuanming; Yang, Chengwen; Wang, Wei; Wang, Ping; Deng, Jun

    2016-01-01

    Abstract Background: Radiation-induced heart disease (RIHD), which affects the patients’ prognosis with both acute and late side effects, has been published extensively in the radiotherapy of breast cancer, lymphoma and other benign diseases. Studies on RIHD in lung cancer radiotherapy, however, are less extensive and clear even though the patients with lung cancer are delivered with higher doses to the heart during radiation treatment. Methods: In this article, after extensive literature search and analysis, we reviewed the current evidence on RIHD in lung cancer patients after their radiation treatments and investigated the potential risk factors for RIHD as compared to other types of cancers. Result: Cardiac toxicity has been found highly relevant in lung cancer radiotherapy. So far, the crude incidence of cardiac complications in the lung cancer patients after radiotherapy has been up to 33%. Conclusion: The dose to the heart, the lobar location of tumor, the treatment modality, the history of heart and pulmonary disease and smoking were considered as potential risk factors for RIHD in lung cancer radiotherapy. As treatment techniques improve over the time with better prognosis for lung cancer survivors, an improved prediction model can be established to further reduce the cardiac toxicity in lung cancer radiotherapy. PMID:27741117

  4. Gamma radiation induced changes in nuclear waste glass containing Eu

    NASA Astrophysics Data System (ADS)

    Mohapatra, M.; Kadam, R. M.; Mishra, R. K.; Kaushik, C. P.; Tomar, B. S.; Godbole, S. V.

    2011-10-01

    Gamma radiation induced changes were investigated in sodium-barium borosilicate glasses containing Eu. The glass composition was similar to that of nuclear waste glasses used for vitrifying Trombay research reactor nuclear waste at Bhabha Atomic Research Centre, India. Photoluminescence (PL) and electron paramagnetic resonance (EPR) techniques were used to study the speciation of the rare earth (RE) ion in the matrix before and after gamma irradiation. Judd-Ofelt ( J- O) analyses of the emission spectra were done before and after irradiation. The spin counting technique was employed to quantify the number of defect centres formed in the glass at the highest gamma dose studied. PL data suggested the stabilisation of the trivalent RE ion in the borosilicate glass matrix both before and after irradiation. It was also observed that, the RE ion distributes itself in two different environments in the irradiated glass. From the EPR data it was observed that, boron oxygen hole centre based radicals are the predominant defect centres produced in the glass after irradiation along with small amount of E’ centres. From the spin counting studies the concentration of defect centres in the glass was calculated to be 350 ppm at 900 kGy. This indicated the fact that bulk of the glass remained unaffected after gamma irradiation up to 900 kGy.

  5. Interleukin-32 Positively Regulates Radiation-Induced Vascular Inflammation

    SciTech Connect

    Kobayashi, Hanako; Yazlovitskaya, Eugenia M.; Lin, P. Charles

    2009-08-01

    Purpose: To study the role of interleukin-32 (IL-32), a novel protein only detected in human tissues, in ionizing radiation (IR)-induced vascular inflammation. Methods and Materials: Irradiated (0-6 Gy) human umbilical vein endothelial cells treated with or without various agents-a cytosolic phospholipase A2 (cPLA2) inhibitor, a cyclooxygenase-2 (Cox-2) inhibitor, or lysophosphatidylcholines (LPCs)-were used to assess IL-32 expression by Northern blot analysis and quantitative reverse transcriptase-polymerase chain reaction. Expression of cell adhesion molecules and leukocyte adhesion to endothelial cells using human acute monocytic leukemia cell line (THP-1) cells was also analyzed. Results: Ionizing radiation dramatically increased IL-32 expression in vascular endothelial cells through multiple pathways. Ionizing radiation induced IL-32 expression through nuclear factor {kappa}B activation, through induction of cPLA2 and LPC, as well as induction of Cox-2 and subsequent conversion of arachidonic acid to prostacyclin. Conversely, blocking nuclear factor {kappa}B, cPLA2, and Cox-2 activity impaired IR-induced IL-32 expression. Importantly, IL-32 significantly enhanced IR-induced expression of vascular cell adhesion molecules and leukocyte adhesion on endothelial cells. Conclusion: This study identifies IL-32 as a positive regulator in IR-induced vascular inflammation, and neutralization of IL-32 may be beneficial in protecting from IR-induced inflammation.

  6. Radiation induced destruction of thebaine, papaverine and noscapine in methanol

    NASA Astrophysics Data System (ADS)

    Kantoğlu, Ömer; Ergun, Ece

    2016-07-01

    The presence of methanol decreases the efficiency of radiation-induced decomposition of alkaloids in wastewater. Intermediate products were observed before the complete degradation of irradiated alkaloids. In order to identify the structure of the by-products and the formation pathway, thebaine, papaverine and noscapine solutions were prepared in pure methanol and irradiated using a 60Co gamma cell at absorbed doses of 0, 1, 3, 5, 7, 10, 30, 50 and 80 kGy. The dose-dependent alkaloid degradation and by-product formation were monitored by ESI mass spectrometer. Molecular structures of the by-products and reaction pathways were proposed. Oxygenated and methoxy group containing organic compounds was observed in the mass spectra of irradiated alkaloids. At initial dose values oxygenated by-products were formed due to the presence of dissolved oxygen in solutions. After the consumption of dissolved oxygen with radicals, the main mechanism was addition of solvent radicals to alkaloid structure. However, it was determined that alkaloids and by-products were completely degraded at doses higher than 50 kGy. The G-value and degradation efficiency of alkaloids were also evaluated.

  7. Radiation-induced removal of sulphadiazine antibiotics from wastewater.

    PubMed

    Liu, Yuankun; Hu, Jun; Wang, Jianlong

    2014-08-01

    The radiation-induced removal of sulphadiazine (SD) belonging to the heterocyclic sulphonamides pharmaceuticals was investigated by gamma irradiation at different conditions in laboratory scale. The influence of initial SD concentrations, pH values, 02 and N2 on SD degradation was determined. The experimental results showed that gamma-ray irradiation was efficient for removing SD from wastewater. SD could be completely removed at an absorbed dose of 10 kGy. The degradation kinetics of SD conformed to the first-order kinetic equation. When SD concentration was in the range of 10-30 mg/L, the dose constant (d) decreased with an increasing initial SD concentration. The mineralization of SD, in terms of total organic carbon removal, was not obvious at a low absorbed dose, but it increased to more than 75% at 100 kGy. The biodegradability of SD was improved after irradiation, suggesting that irradiation could be used as a pretreatment technology for treating SD-containing wastewater. The possible degradation pathway of SD was tentatively proposed based on the analysis of intermediate products during gamma irradiation.

  8. Radiation-induced optic neuropathy: A magnetic resonance imaging study

    SciTech Connect

    Guy, J.; Mancuso, A.; Beck, R.; Moster, M.L.; Sedwick, L.A.; Quisling, R.G.; Rhoton, A.L. Jr.; Protzko, E.E.; Schiffman, J. )

    1991-03-01

    Optic neuropathy induced by radiation is an infrequent cause of delayed visual loss that may at times be difficult to differentiate from compression of the visual pathways by recurrent neoplasm. The authors describe six patients with this disorder who experienced loss of vision 6 to 36 months after neurological surgery and radiation therapy. Of the six patients in the series, two had a pituitary adenoma and one each had a metastatic melanoma, multiple myeloma, craniopharyngioma, and lymphoepithelioma. Visual acuity in the affected eyes ranged from 20/25 to no light perception. Magnetic resonance (MR) imaging showed sellar and parasellar recurrence of both pituitary adenomas, but the intrinsic lesions of the optic nerves and optic chiasm induced by radiation were enhanced after gadolinium-diethylenetriaminepenta-acetic acid (DTPA) administration and were clearly distinguishable from the suprasellar compression of tumor. Repeated MR imaging showed spontaneous resolution of gadolinium-DTPA enhancement of the optic nerve in a patient who was initially suspected of harboring recurrence of a metastatic malignant melanoma as the cause of visual loss. The authors found the presumptive diagnosis of radiation-induced optic neuropathy facilitated by MR imaging with gadolinium-DTPA. This neuro-imaging procedure may help avert exploratory surgery in some patients with recurrent neoplasm in whom the etiology of visual loss is uncertain.

  9. Radiation-induced chromosomal instability in human mammary epithelial cells

    NASA Astrophysics Data System (ADS)

    Durante, M.; Grossi, G. F.; Yang, T. C.

    Karyotypes of human cells surviving X- and alpha-irradiation have been studied. Human mammary epithelial cells of the immortal, non-tumorigenic cell line H184B5 F5-1 M/10 were irradiated and surviving clones isolated and expanded in culture. Cytogenetic analysis was performed using dedicated software with an image analyzer. We have found that both high- and low-LET radiation induced chromosomal instability in long-term cultures, but with different characteristics. Complex chromosomal rearrangements were observed after X-rays, while chromosome loss predominated after alpha-particles. Deletions were observed in both cases. In clones derived from cells exposed to alpha-particles, some cells showed extensive chromosome breaking and double minutes. Genomic instability was correlated to delayed reproductive death and neoplastic transformation. These results indicate that chromosomal instability is a radiation-quality-dependent effect which could determine late genetic effects, and should therefore be carefully considered in the evaluation of risk for space missions.

  10. Investigations of radiation-induced and carrier-enhanced conductivity

    NASA Astrophysics Data System (ADS)

    Meulenberg, A., Jr.; Parker, L. W.; Yadlowski, E. J.; Hazelton, R. C.

    1985-03-01

    A steady-state carrier computer code, PECK (Parker Enhanced Carrier Kinetics), that predicts the radiation-induced conductivity (RIC) produced in a dielectric by an electron beam was developed. The model, which assumes instantly-trapped holes, was then applied to experimental measurements on thin Kapton samples penetrated by an electron beam. Measurements at high bias were matched in the model by an appropriate choice for the trap-modulated electron mobility. A fractional split between front and rear currents measured at zone bias is explained on the basis of beam-scattering. The effects of carrier-enhanced conductivity (CEC) on data obtained for thick, free-surface Kapton samples is described by using an analytical model that incorporates field injection of carriers from the RIC region. The computer code, LWPCHARGE, modified for carrier transport, is also used to predict partial penetration effects associated with CEC in the unirradiated region. Experimental currents and surface voltages, when incorporated in the appropriate models, provide a value for the trap modulated mobility that is in essential agreement with the RIC results.

  11. Investigations of radiation-induced and carrier-enhanced conductivity

    NASA Technical Reports Server (NTRS)

    Meulenberg, A., Jr.; Parker, L. W.; Yadlowski, E. J.; Hazelton, R. C.

    1985-01-01

    A steady-state carrier computer code, PECK (Parker Enhanced Carrier Kinetics), that predicts the radiation-induced conductivity (RIC) produced in a dielectric by an electron beam was developed. The model, which assumes instantly-trapped holes, was then applied to experimental measurements on thin Kapton samples penetrated by an electron beam. Measurements at high bias were matched in the model by an appropriate choice for the trap-modulated electron mobility. A fractional split between front and rear currents measured at zone bias is explained on the basis of beam-scattering. The effects of carrier-enhanced conductivity (CEC) on data obtained for thick, free-surface Kapton samples is described by using an analytical model that incorporates field injection of carriers from the RIC region. The computer code, LWPCHARGE, modified for carrier transport, is also used to predict partial penetration effects associated with CEC in the unirradiated region. Experimental currents and surface voltages, when incorporated in the appropriate models, provide a value for the trap modulated mobility that is in essential agreement with the RIC results.

  12. Mechanisms of radiation-induced neoplastic cell transformation

    SciTech Connect

    Yang, T.C.H.; Tobias, C.A.

    1984-04-01

    Studies with cultured mammalian cells demonstrated clearly that radiation can transform cells directly and can enhance the cell transformation by oncogenic DNA viruses. In general, high-LET heavy-ion radiation can be more effective than X and gamma rays in inducing neoplastic cell transformation. Various experimental results indicate that radiation-induced DNA damage, most likely double-strand breaks, is important for both the initiation of cell transformation and for the enhancement of viral transformation. Some of the transformation and enhancement lesions can be repaired properly in the cell, and the amount of irrepairable lesions produced by a given dose depends on the quality of radiation. An inhibition of repair processes with chemical agents can increase the transformation frequency of cells exposed to radiation and/or oncogenic viruses, suggesting that repair mechanisms may play an important role in the radiation transformation. The progression of radiation-transformed cells appears to be a long and complicated process that can be modulated by some nonmutagenic chemical agents, e.g., DMSO. Normal cells can inhibit the expression of transforming properties of tumorigenic cells through an as yet unknown mechanism. The progression and expression of transformation may involve some epigenetic changes in the irradiated cells. 38 references, 15 figures, 1 table.

  13. Radiation-induced sarcomas of the chest wall

    SciTech Connect

    Souba, W.W.; McKenna, R.J. Jr.; Meis, J.; Benjamin, R.; Raymond, A.K.; Mountain, C.F.

    1986-02-01

    Sixteen patients are presented who had sarcomas of the chest wall at a site where a prior malignancy had been irradiated. The first malignancies included breast cancer (ten cases), Hodgkin's disease (four cases), and others (two cases). Radiation doses varied from 4200 to 5500 R (mean, 4900 R). The latency period ranged from 5 to 28 years (mean, 13 years). The histologic types of the radiation-induced sarcomas were as follows: malignant fibrous histiocytoma, nine cases; osteosarcoma, six cases; and malignant mesenchymoma, one case. The only long-term survivor is alive and well 12 years after resection of a clavicular chondroblastic osteosarcoma. Three cases were recently diagnosed. Despite aggressive multimodality treatment, the remaining 13 patients have all died from their sarcomas (mean survival, 13.5 months). All patients have apparently been cured of their first malignancies. Chemotherapy was ineffective. No treatment, including forequarter amputation, appeared to palliate the patients with supraclavicular soft tissue sarcomas. Major chest wall resection offered good palliation for seven of eight patients with sarcomas arising in the sternum or lateral chest wall. Close follow-up is needed to detect signs of these sarcomas in the ever-increasing number of patients receiving therapeutic irradiation.

  14. Radiation-induced chromosomal instability in human mammary epithelial cells

    NASA Technical Reports Server (NTRS)

    Durante, M.; Grossi, G. F.; Yang, T. C.

    1996-01-01

    Karyotypes of human cells surviving X- and alpha-irradiation have been studied. Human mammary epithelial cells of the immortal, non-tumorigenic cell line H184B5 F5-1 M/10 were irradiated and surviving clones isolated and expanded in culture. Cytogenetic analysis was performed using dedicated software with an image analyzer. We have found that both high- and low-LET radiation induced chromosomal instability in long-term cultures, but with different characteristics. Complex chromosomal rearrangements were observed after X-rays, while chromosome loss predominated after alpha-particles. Deletions were observed in both cases. In clones derived from cells exposed to alpha-particles, some cells showed extensive chromosome breaking and double minutes. Genomic instability was correlated to delayed reproductive death and neoplastic transformation. These results indicate that chromosomal instability is a radiation-quality-dependent effect which could determine late genetic effects, and should therefore be carefully considered in the evaluation of risk for space missions.

  15. Temporal distributions of risk for radiation-induced cancers.

    PubMed

    Land, C E

    1987-01-01

    Observations of cancer risk in irradiated human populations over time after exposure suggest that there are at least two, and perhaps more, very different patterns of temporal distribution of risk for radiation-induced cancer. The first, exemplified by bone sarcoma following therapeutic injection of 224Ra and chronic granulocytic leukemia in Japanese A-bomb survivors, is an early, wave-like pulse consisting of an increase in risk followed by a gradual decline back to baseline levels. The second, exemplified by breast cancer following a brief exposure to external gamma ray or X ray, and by lung cancer and stomach cancer in A-bomb survivors, is an increase in relative risk over about 10 years to a value which appears to remain constant over time thereafter. The first pattern suggests that tumor growth kinetics may play a central role in the temporal distribution of risk following exposure, while the second seems more consistent with multi-event models for carcinogenesis, in which radiation or some other cause of early events must be followed by one or more later events whose frequencies depend mainly on attained age. There are, however, other data that appear to conform to neither of the two models just mentioned. Influences of other cancer causes, like tobacco smoking, are potentially serious confounding factors in studies of induction period.

  16. Radiation-induced chromosome damage in astronauts' lymphocytes.

    PubMed

    Testard, I; Ricoul, M; Hoffschir, F; Flury-Herard, A; Dutrillaux, B; Fedorenko, B; Gerasimenko, V; Sabatier, L

    1996-10-01

    The increased number of manned space missions has made it important to estimate the biological risks encountered by astronauts. As they are exposed to cosmic rays, especially ions with high linear energy transfer (LET), it is necessary to estimate the doses they receive. The most sensitive biological dosimetry used is based on the quantification of radiation-induced chromosome damage to human lymphocytes. After the space missions ANTARES (1992) and ALTAIR (1993), we performed cytogenetic analysis of blood samples from seven astronauts who had spent from 2 weeks to 6 months in space. After 2 or 3 weeks, the X-ray equivalent dose was found to be below the cytogenetic detection level of 20 mGy. After 6 months, the biological dose greatly varied among the astronauts, from 95 to 455 mGy equivalent dose. These doses are in the same range as those estimated by physical dosimetry (90 mGy absorbed dose and 180 mSv equivalent dose). Some blood cells exhibited the same cytogenetic pattern as the 'rogue cells' occasionally observed in controls, but with a higher frequency. We suggest that rogue cells might result from irradiation with high-LET particles of cosmic origin. However, the responsibility of such cells for the long-term effects of cosmic irradiation remains unknown and must be investigated.

  17. Perinatal radiation-induced renal damage in the beagle

    SciTech Connect

    Jaenke, R.S.; Angleton, G.M. )

    1990-04-01

    The developing perinatal kidney is particularly sensitive to radiation. The pathogenesis of the radiation-induced lesion is related to the destruction of outer cortical developing nephrons and direct radiation injury with secondary hemodynamic alterations in remnant nephrons. In this study, which is part of a life span investigation of the effects of whole-body gamma radiation during prenatal and early postnatal life, dogs were given 0, 0.16, 0.83, or 1.25 Gy irradiation at either 55 days postcoitus or 2 days postpartum and were examined morphometrically and histopathologically at 70 days of age. Although irradiated dogs showed no reduction in the total number of nephrons per kidney, there was a significant increase in the total number and relative percentage of immature, dysplastic glomeruli. In addition, deeper cortical glomeruli of irradiated kidneys exhibited mesangial sclerosis similar to that associated with progressive renal failure in our previous studies. These findings are in accord with those reported at doses of 2.24 to 3.57 Gy and demonstrate that the perinatal kidney is affected by radiation doses much lower than previously demonstrated.

  18. Effects of contrast medium on radiation-induced chromosome aberrations

    SciTech Connect

    Matsubara, S.; Suzuki, S.; Suzuki, H.; Kuwabara, Y.; Okano, T.

    1982-07-01

    The effects of contrast material (meglumine iothalamate) on radiation-induced chromosome aberrations were investigated in studies on the lymphocytes of patients who had undergone diagnostic radiography and in in vitro experiments with diagnostic x rays and /sup 60/Co gamma rays. Chromosome and chromatid aberrations were found to increase significantly with increasing concentrations of contrast material that were added at irradiation. However, the aberrations were not associated with elevation of the ratio of dicentric and ring chromosomes to the number of cells with unstable chromosome aberrations at the first mitosis. Lymphocytes irradiated in the absence of contrast material did not show an increase in chromosome-type aberrations when the agent was given in increasing concentrations during subsequent incubation, but there were greater numbers of chromatid gaps and breaks. When lymphocytes were exposed to 400 R (103.2 mC/kg) of /sup 60/Co gamma rays, the presence of contrast agent did not increase the yield of dicentric and ring chromosomes, but induced a marked delay in cell proliferation, especially in lymphocytes with more heavily damaged chromosomes. In additional examination, the contrast agent itself induced sister chromatid exchanges in lymphocytes.

  19. Glycyrrhetinic acid alleviates radiation-induced lung injury in mice

    PubMed Central

    Chen, Jinmei; Zhang, Weijian; Zhang, Lurong; Zhang, Jiemin; Chen, Xiuying; Yang, Meichun; Chen, Ting; Hong, Jinsheng

    2017-01-01

    Radiation-induced lung injury (RILI) is a common complication of thoracic radiotherapy, but efficacious therapy for RILI is lacking. This study ascertained whether glycyrrhetinic acid (GA; a functional hydrolyzed product of glycyrrhizic acid, which is extracted from herb licorice) can protect against RILI and investigated its relationship to the transforming growth factor (TGF)-β1/Smads signaling pathway. C57BL/6 mice were divided into four groups: a control group, a GA group and two irradiation (IR) groups. IR groups were exposed to a single fraction of X-rays (12 Gy) to the thorax and administered normal saline (IR + NS group) or GA (IR + GA group). Two days and 17 days after irradiation, histologic analyses were performed to assess the degree of lung injury, and the expression of TGF-β1, Smad2, Smad3 and Smad7 was recorded. GA administration mitigated the histologic changes of lung injury 2 days and 17 days after irradiation. Protein and mRNA expression of TGF-β1, Smad2 and Smad3, and the mRNA level of Smad7, in lung tissue were significantly elevated after irradiation. GA decreased expression of TGF-β1, Smad2 and Smad3 in lung tissue, but did not increase Smad7 expression. GA can protect against early-stage RILI. This protective effect may be associated with inhibition of the TGF-β1/Smads signaling pathway. PMID:27672101

  20. Molecular Mechanisms and Treatment of Radiation-Induced Lung Fibrosis

    PubMed Central

    Ding, Nian-Hua; Li, Jian Jian; Sun, Lun-Quan

    2014-01-01

    Radiation-induced lung fibrosis (RILF) is a severe side effect of radiotherapy in lung cancer patients that presents as a progressive pulmonary injury combined with chronic inflammation and exaggerated organ repair. RILF is a major barrier to improving the cure rate and well-being of lung cancer patients because it limits the radiation dose that is required to effectively kill tumor cells and diminishes normal lung function. Although the exact mechanism is unclear, accumulating evidence suggests that various cells, cytokines and regulatory molecules are involved in the tissue reorganization and immune response modulation that occur in RILF. In this review, we will summarize the general symptoms, diagnostics, and current understanding of the cells and molecular factors that are linked to the signaling networks implicated in RILF. Potential approaches for the treatment of RILF will also be discussed. Elucidating the key molecular mediators that initiate and control the extent of RILF in response to therapeutic radiation may reveal additional targets for RILF treatment to significantly improve the efficacy of radiotherapy for lung cancer patients. PMID:23909719

  1. Radiation induced thyroid neoplasms 1920 to 1987: A vanishing problem

    SciTech Connect

    Mehta, M.P.; Goetowski, P.G.; Kinsella, T.J.

    1989-06-01

    Radiation for benign diseases has been implicated as an etiologic factor in thyroid cancer. From 1930-60, over 2 million children may have been exposed to therapeutic radiation and it is estimated that up to 7% may develop thyroid cancer after a 5-40 year latency. Thyroid stimulating hormone, secondary to radioinduced hypothyroidism, has been implicated as causative in animals. Such data has led to expensive screening programs in high risk patients. Because of a decline in irradiation for benign diseases in children over the last 2 decades, we questioned whether the incidence of radiation induced thyroid neoplasms (RITN) was also decreasing. Twenty-six of 227 patients (11%) with thyroid malignancies seen at our institution from 1974-87 had a history of previous head and neck irradiation. These included 13 papillary, 3 follicular, and 7 mixed carcinomas as well as 2 lymphomas and 1 synovial cell sarcoma. None of these 26 patients had abnormal thyroid function tests at presentation. Mean latency from irradiation to the diagnosis of thyroid cancer was 25.4 years (6-55 year range). Compared to the reported increasing incidence of RITN from 1940-70, there appears to be a significant decrease since 1970. Based on our analysis, the use of expensive screening programs in high risk populations may no longer be warranted. Additionally, the routine use of thyroid replacement in previously irradiated chemically hypothyroid patients is not recommended.30 references.

  2. Gamma radiation induces hydrogen absorption by copper in water

    NASA Astrophysics Data System (ADS)

    Lousada, Cláudio M.; Soroka, Inna L.; Yagodzinskyy, Yuriy; Tarakina, Nadezda V.; Todoshchenko, Olga; Hänninen, Hannu; Korzhavyi, Pavel A.; Jonsson, Mats

    2016-04-01

    One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories.

  3. Massive hemothorax: A rare complication after supraclavicular brachial plexus block.

    PubMed

    Singh, Shiv Kumar; Katyal, Surabhi; Kumar, Amit; Kumar, Pawan

    2014-01-01

    Plexus block is the preferred anesthesia plan for upper limb surgeries. Among the known complications, hematoma formation following the vascular trauma is often occur but this complication is frequently underreported. We present a case where a massive hemothorax developed post operatively in a patient who underwent resection of giant cell tumor of the right hand radius bone followed by arthroplasty under brachial plexus block using supraclavicular approach. This case report attempts to highlight the essence of remaining vigilant postoperatively for first initial days after brachial plexus block, especially after failed or multiple attempts. Ultrasound guided technique in combination with nerve stimulator has proven to be more reliable and safer than traditional techniques.

  4. Acute presentation of brachial plexus schwannoma secondary to infarction.

    PubMed

    Sidani, Charif; Saraf-Lavi, Efrat; Lyapichev, Kirill A; Nadji, Mehrdad; Levi, Allan D

    2015-06-01

    Schwannomas of the brachial plexus are rare and typically present as slowly growing masses. We describe a case of a 37-year-old female who presented with acute onset of severe left upper extremity pain. Magnetic resonance imaging (MRI) showed a 2.3 × 2.1 cm peripherally enhancing centrally cystic lesion in the left axilla, along the cords of the left brachial plexus, with significant surrounding edema and enhancement. The mass was surgically removed. Pathology was consistent with a schwannoma with infarction. The pain completely resolved immediately after surgery.

  5. ATM Heterozygosity and the Development of Radiation-Induced Erectile Dysfunction and Urinary Morbidity Following Radiotherapy for Prostate Cancer

    DTIC Science & Technology

    2007-02-01

    whether there is a correlation between the presence of a mutation, development of a radiation -induced complication , and impairment of ATM protein...associated with the development of radiation -induced proctitis following prostate cancer radiotherapy for patients who receive the full prescription...possession of genetic variants in the ATM gene is associated with the development of radiation -induced proctitis following prostate cancer

  6. Effects of helium and hydrogen on radiation-induced microstructural changes in austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Jin, Hyung-Ha; Ko, Eunsol; Lim, Sangyeop; Kwon, Junhyun

    2015-09-01

    Microstructural changes in austenitic stainless steel by helium, hydrogen, and iron ion irradiation were investigated with transmission electron microscopy. Typical radiation-induced changes, such as the formation of Frank loops in the matrix and radiation-induced segregation (RIS) or depletion at grain boundaries, were observed after ion irradiation. The helium ion irradiation led to the formation of cavities both at grain boundaries and in the matrix, as well as the development of smaller Frank loops. The hydrogen ion irradiation generated stronger RIS behavior at the grain boundaries compared to irradiation with helium and iron ions. The effects of helium and hydrogen on radiation-induced microstructural changes were discussed.

  7. Dosimetric Analysis of Radiation-Induced Gastric Bleeding

    PubMed Central

    Feng, Mary; Normolle, Daniel; Pan, Charlie C.; Dawson, Laura A.; Amarnath, Sudha; Ensminger, William D.; Lawrence, Theodore S.; Ten Haken, Randall K.

    2012-01-01

    Purpose Radiation-induced gastric bleeding has been poorly understood. In this study, we describe dosimetric predictors for gastric bleeding after fractionated radiotherapy and compare several predictive models. Materials & Methods The records of 139 sequential patients treated with 3-dimensional conformal radiotherapy (3D-CRT) for intrahepatic malignancies between January 1999 and April 2002 were reviewed. Median follow-up was 7.4 months. Logistic regression and Lyman normal tissue complication probability (NTCP) models for the occurrence of ≥ grade 3 gastric bleed were fit to the data. The principle of maximum likelihood was used to estimate parameters for all models. Results Sixteen of 116 evaluable patients (14%) developed gastric bleeds, at a median time of 4.0 months (mean 6.5 months, range 2.1–28.3 months) following completion of RT. The median and mean of the maximum doses to the stomach were 61 and 63 Gy (range 46 Gy–86 Gy), respectively, after bio-correction to equivalent 2 Gy daily fractions. The Lyman NTCP model with parameters adjusted for cirrhosis was most predictive of gastric bleed (AUROC=0.92). Best fit Lyman NTCP model parameters were n =0.10, and m =0.21, with TD50(normal) =56 Gy and TD50(cirrhosis) = 22 Gy. The low n value is consistent with the importance of maximum dose; a lower TD50 value for the cirrhosis patients points out their greater sensitivity. Conclusion This study demonstrates that the Lyman NTCP model has utility for predicting gastric bleeding, and that the presence of cirrhosis greatly increases this risk. These findings should facilitate the design of future clinical trials involving high-dose upper abdominal radiation. PMID:22541965

  8. Dosimetric Analysis of Radiation-induced Gastric Bleeding

    SciTech Connect

    Feng, Mary; Normolle, Daniel; Pan, Charlie C.; Dawson, Laura A.; Amarnath, Sudha; Ensminger, William D.; Lawrence, Theodore S.; Ten Haken, Randall K.

    2012-09-01

    Purpose: Radiation-induced gastric bleeding has been poorly understood. In this study, we described dosimetric predictors for gastric bleeding after fractionated radiation therapy. Methods and Materials: The records of 139 sequential patients treated with 3-dimensional conformal radiation therapy (3D-CRT) for intrahepatic malignancies were reviewed. Median follow-up was 7.4 months. The parameters of a Lyman normal tissue complication probability (NTCP) model for the occurrence of {>=}grade 3 gastric bleed, adjusted for cirrhosis, were fitted to the data. The principle of maximum likelihood was used to estimate parameters for NTCP models. Results: Sixteen of 116 evaluable patients (14%) developed gastric bleeds at a median time of 4.0 months (mean, 6.5 months; range, 2.1-28.3 months) following completion of RT. The median and mean maximum doses to the stomach were 61 and 63 Gy (range, 46-86 Gy), respectively, after biocorrection of each part of the 3D dose distributions to equivalent 2-Gy daily fractions. The Lyman NTCP model with parameters adjusted for cirrhosis predicted gastric bleed. Best-fit Lyman NTCP model parameters were n=0.10 and m=0.21 and with TD{sub 50} (normal) = 56 Gy and TD{sub 50} (cirrhosis) = 22 Gy. The low n value is consistent with the importance of maximum dose; a lower TD{sub 50} value for the cirrhosis patients points out their greater sensitivity. Conclusions: This study demonstrates that the Lyman NTCP model has utility for predicting gastric bleeding and that the presence of cirrhosis greatly increases this risk. These findings should facilitate the design of future clinical trials involving high-dose upper abdominal radiation.

  9. Chronic radiation-induced dermatitis: challenges and solutions

    PubMed Central

    Spałek, Mateusz

    2016-01-01

    Chronic radiation dermatitis is a late side effect of skin irradiation, which may deteriorate patients’ quality of life. There is a lack of precise data about its incidence; however, several risk factors may predispose to the development of this condition. It includes radiotherapy dose, fractionation, technique, concurrent systemic therapy, comorbidities, and personal and genetic factors. Chronic radiation dermatitis is mostly caused by the imbalance of proinflammatory and profibrotic cytokines. Clinical manifestation includes changes in skin appearance, wounds, ulcerations, necrosis, fibrosis, and secondary cancers. The most severe complication of irradiation is extensive radiation-induced fibrosis (RIF). RIF can manifest in many ways, such as skin induration and retraction, lymphedema or restriction of joint motion. Diagnosis of chronic radiation dermatitis is usually made by clinical examination. In case of unclear clinical manifestation, a biopsy and histopathological examination are recommended to exclude secondary malignancy. The most effective prophylaxis of chronic radiation dermatitis is the use of proper radiation therapy techniques to avoid unnecessary irradiation of healthy skin. Treatment of chronic radiation dermatitis is demanding. The majority of the interventions are based only on clinical practice. Telangiectasia may be treated with pulse dye laser therapy. Chronic postirradiation wounds need special dressings. In case of necrosis or severe ulceration, surgical intervention may be considered. Management of RIF should be complex. Available methods are rehabilitative care, pharmacotherapy, hyperbaric oxygen therapy, and laser therapy. Future challenges include the assessment of late skin toxicity in modern irradiation techniques. Special attention should be paid on genomics and radiomics that allow scientists and clinicians to select patients who are at risk of the development of chronic radiation dermatitis. Novel treatment methods and clinical

  10. [Radiation-induced tumors of the nervous system in man].

    PubMed

    Hubert, D; Bertin, M

    1993-11-01

    The risk of developing a tumor of the nervous system in humans is analysed in several studies of populations, exposed to ionising radiation for medical reasons, or exposed to military or occupational radiation. The main data come from series of patients who underwent radiotherapy during childhood: a high incidence of tumors of the nervous system is found after irradiation of one to a few grays as treatment of a benign disease (especially tinea capitis), as well as after irradiation at higher doses of a few tens of grays for the treatment of cancer (in particular cerebral irradiation in acute lymphoblastic leukaemia). The type of radiation-induced tumors is variable, but meningioma is more frequent after low doses and glioma and sarcoma after higher doses used in the treatment of neoplastic diseases. A dose-effect relationship appeared between the risk of tumor of the nervous system and the radiation dose. The risk was higher when radiation was delivered at a younger age. Much less data are available after radiotherapy in the adulthood, but an increased risk of cerebral tumor appears in the series of ankylosing spondylitis patients. As for the exposures to radiodiagnosis exams, the main problem is the risk of cerebral tumor in children whose mother has undergone abdominal or pelvic X-rays during pregnancy. No risk of neurologic tumor was found in the A-bomb survivors irradiated at Hiroshima and Nagasaki. Occupational exposure to ionising radiation has been incriminated in the first radiologists exposed to high doses. In nuclear industry workers, the results of epidemiological studies are contradictory and at the present time it is not possible to link their radiologic exposure with a risk of tumor of the nervous system. In populations living near nuclear plants, mortality due to tumors of the nervous system was not increased.

  11. Novel concepts in radiation-induced cardiovascular disease

    PubMed Central

    Cuomo, Jason R; Sharma, Gyanendra K; Conger, Preston D; Weintraub, Neal L

    2016-01-01

    Radiation-induced cardiovascular disease (RICVD) is the most common nonmalignant cause of morbidity and mortality among cancer survivors who have undergone mediastinal radiation therapy (RT). Cardiovascular complications include effusive or constrictive pericarditis, cardiomyopathy, valvular heart disease, and coronary/vascular disease. These are pathophysiologically distinct disease entities whose prevalence varies depending on the timing and extent of radiation exposure to the heart and great vessels. Although refinements in RT dosimetry and shielding will inevitably limit future cases of RICVD, the increasing number of long-term cancer survivors, including those treated with older higher-dose RT regimens, will ensure a steady flow of afflicted patients for the foreseeable future. Thus, there is a pressing need for enhanced understanding of the disease mechanisms, and improved detection methods and treatment strategies. Newly characterized mechanisms responsible for the establishment of chronic fibrosis, such as oxidative stress, inflammation and epigenetic modifications, are discussed and linked to potential treatments currently under study. Novel imaging modalities may serve as powerful screening tools in RICVD, and recent research and expert opinion advocating their use is introduced. Data arguing for the aggressive use of percutaneous interventions, such as transcutaneous valve replacement and drug-eluting stents, are examined and considered in the context of prior therapeutic approaches. RICVD and its treatment options are the subject of a rich and dynamic body of research, and patients who are at risk or suffering from this disease will benefit from the care of physicians with specialty expertise in the emerging field of cardio-oncology. PMID:27721934

  12. Chronic radiation-induced dermatitis: challenges and solutions.

    PubMed

    Spałek, Mateusz

    2016-01-01

    Chronic radiation dermatitis is a late side effect of skin irradiation, which may deteriorate patients' quality of life. There is a lack of precise data about its incidence; however, several risk factors may predispose to the development of this condition. It includes radiotherapy dose, fractionation, technique, concurrent systemic therapy, comorbidities, and personal and genetic factors. Chronic radiation dermatitis is mostly caused by the imbalance of proinflammatory and profibrotic cytokines. Clinical manifestation includes changes in skin appearance, wounds, ulcerations, necrosis, fibrosis, and secondary cancers. The most severe complication of irradiation is extensive radiation-induced fibrosis (RIF). RIF can manifest in many ways, such as skin induration and retraction, lymphedema or restriction of joint motion. Diagnosis of chronic radiation dermatitis is usually made by clinical examination. In case of unclear clinical manifestation, a biopsy and histopathological examination are recommended to exclude secondary malignancy. The most effective prophylaxis of chronic radiation dermatitis is the use of proper radiation therapy techniques to avoid unnecessary irradiation of healthy skin. Treatment of chronic radiation dermatitis is demanding. The majority of the interventions are based only on clinical practice. Telangiectasia may be treated with pulse dye laser therapy. Chronic postirradiation wounds need special dressings. In case of necrosis or severe ulceration, surgical intervention may be considered. Management of RIF should be complex. Available methods are rehabilitative care, pharmacotherapy, hyperbaric oxygen therapy, and laser therapy. Future challenges include the assessment of late skin toxicity in modern irradiation techniques. Special attention should be paid on genomics and radiomics that allow scientists and clinicians to select patients who are at risk of the development of chronic radiation dermatitis. Novel treatment methods and clinical

  13. Posterior subscapular dissection: An improved approach to the brachial plexus for human anatomy students.

    PubMed

    Hager, Shaun; Backus, Timothy Charles; Futterman, Bennett; Solounias, Nikos; Mihlbachler, Matthew C

    2014-05-01

    Students of human anatomy are required to understand the brachial plexus, from the proximal roots extending from spinal nerves C5 through T1, to the distal-most branches that innervate the shoulder and upper limb. However, in human cadaver dissection labs, students are often instructed to dissect the brachial plexus using an antero-axillary approach that incompletely exposes the brachial plexus. This approach readily exposes the distal segments of the brachial plexus but exposure of proximal and posterior segments require extensive dissection of neck and shoulder structures. Therefore, the proximal and posterior segments of the brachial plexus, including the roots, trunks, divisions, posterior cord and proximally branching peripheral nerves often remain unobserved during study of the cadaveric shoulder and brachial plexus. Here we introduce a subscapular approach that exposes the entire brachial plexus, with minimal amount of dissection or destruction of surrounding structures. Lateral retraction of the scapula reveals the entire length of the brachial plexus in the subscapular space, exposing the brachial plexus roots and other proximal segments. Combining the subscapular approach with the traditional antero-axillary approach allows students to observe the cadaveric brachial plexus in its entirety. Exposure of the brachial dissection in the subscapular space requires little time and is easily incorporated into a preexisting anatomy lab curriculum without scheduling additional time for dissection.

  14. The natural history and management of brachial plexus birth palsy.

    PubMed

    Buterbaugh, Kristin L; Shah, Apurva S

    2016-12-01

    Brachial plexus birth palsy (BPBP) is an upper extremity paralysis that occurs due to traction injury of the brachial plexus during childbirth. Approximately 20 % of children with brachial plexus birth palsy will have residual neurologic deficits. These permanent and significant impacts on upper limb function continue to spur interest in optimizing the management of a problem with a highly variable natural history. BPBP is generally diagnosed on clinical examination and does not typically require cross-sectional imaging. Physical examination is also the best modality to determine candidates for microsurgical reconstruction of the brachial plexus. The key finding on physical examination that determines need for microsurgery is recovery of antigravity elbow flexion by 3-6 months of age. When indicated, both microsurgery and secondary shoulder and elbow procedures are effective and can substantially improve functional outcomes. These procedures include nerve transfers and nerve grafting in infants and secondary procedures in children, such as botulinum toxin injection, shoulder tendon transfers, and humeral derotational osteotomy.

  15. Inflammation and chronic oxidative stress in radiation-induced late normal tissue injury: therapeutic implications.

    PubMed

    Zhao, Weiling; Robbins, Mike E C

    2009-01-01

    The threat of radiation-induced late normal tissue injury limits the dose of radiation that can be delivered safely to cancer patients presenting with solid tumors. Tissue dysfunction and failure, associated with atrophy, fibrosis and/or necrosis, as well as vascular injury, have been reported in late responding normal tissues, including the central nervous system, gut, kidney, liver, lung, and skin. The precise mechanisms involved in the pathogenesis of radiation-induced late normal tissue injury have not been fully elucidated. It has been proposed recently that the radiation-induced late effects are caused, in part, by chronic oxidative stress and inflammation. Increased production of reactive oxygen species, which leads to lipid peroxidation, oxidation of DNA and proteins, as well as activation of pro-inflammatory factors has been observed in vitro and in vivo. In this review, we will present direct and indirect evidence to support this hypothesis. To improve the long-term survival and quality of life for radiotherapy patients, new approaches have been examined in preclinical models for their efficacy in preventing or mitigating the radiation-induced chronic normal tissue injury. We and others have tested drugs that can either attenuate inflammation or reduce chronic oxidative stress in animal models of late radiation-induced normal tissue injury. The effectiveness of renin-angiotensin system blockers, peroxisome proliferator-activated receptor (PPAR) gamma agonists, and antioxidants/antioxidant enzymes in preventing or mitigating the severity of radiation-induced late effects indicates that radiation-induced chronic injury can be prevented and/or treated. This provides a rationale for the design and development of anti-inflammatory-based interventional approaches for the treatment of radiation-induced late normal tissue injury.

  16. Radiation-Induced Topological Disorder in Irradiated Network Structures

    SciTech Connect

    Hobbs, Linn W.

    2002-12-21

    This report summarizes results of a research program investigating the fundamental principles underlying the phenomenon of topological disordering in a radiation environment. This phenomenon is known popularly as amorphization, but is more formally described as a process of radiation-induced structural arrangement that leads in crystals to loss of long-range translational and orientational correlations and in glasses to analogous alteration of connectivity topologies. The program focus has been on a set compound ceramic solids with directed bonding exhibiting structures that can be described as networks. Such solids include SiO2, Si3N4, SiC, which are of interest to applications in fusion energy production, nuclear waste storage, and device manufacture involving ion implantation or use in radiation fields. The principal investigative tools comprise a combination of experimental diffraction-based techniques, topological modeling, and molecular-dynamics simulations that have proven a rich source of information in the preceding support period. The results from the present support period fall into three task areas. The first comprises enumeration of the rigidity constraints applying to (1) more complex ceramic structures (such as rutile, corundum, spinel and olivine structures) that exhibit multiply polytopic coordination units or multiple modes of connecting such units, (2) elemental solids (such as graphite, silicon and diamond) for which a correct choice of polytope is necessary to achieve correct representation of the constraints, and (3) compounds (such as spinel and silicon carbide) that exhibit chemical disorder on one or several sublattices. With correct identification of the topological constraints, a unique correlation is shown to exist between constraint and amorphizability which demonstrates that amorphization occurs at a critical constraint loss. The second task involves the application of molecular dynamics (MD) methods to topologically-generated models

  17. Radiation-induced osteosarcomas in the pediatric population

    SciTech Connect

    Koshy, Matthew; Paulino, Arnold C. . E-mail: apaulino@tmh.tmc.edu; Mai, Wei Y.; Teh, Bin S.

    2005-11-15

    Purpose: Radiation-induced osteosarcomas (R-OS) have historically been high-grade, locally invasive tumors with a poor prognosis. The purpose of this study was to perform a comprehensive literature review and analysis of reported cases dealing with R-OS in the pediatric population to identify the characteristics, prognostic factors, optimal treatment modalities, and overall survival of these patients. Methods and Materials: A MEDLINE/PubMed search of articles written in the English language dealing with OSs occurring after radiotherapy (RT) in the pediatric population yielded 30 studies from 1981 to 2004. Eligibility criteria included patients <21 years of age at the diagnosis of the primary cancer, cases satisfying the modified Cahan criteria, and information on treatment outcome. Factors analyzed included the type of primary cancer treated with RT, the radiation dose and beam energy, the latency period between RT and the development of R-OS, and the treatment, follow-up, and final outcome of R-OS. Results: The series included 109 patients with a median age at the diagnosis of primary cancer of 6 years (range, 0.08-21 years). The most common tumors treated with RT were Ewing's sarcoma (23.9%), rhabdomyosarcoma (17.4%), retinoblastoma (12.8%), Hodgkin's disease (9.2%), brain tumor (8.3%), and Wilms' tumor (6.4%). The median radiation dose was 47 Gy (range, 15-145 Gy). The median latency period from RT to the development of R-OS was 100 months (range, 36-636 months). The median follow-up after diagnosis of R-OS was 18 months (1-172 months). The 3- and 5-year cause-specific survival rate was 43.6% and 42.2%, respectively, and the 3- and 5-year overall survival rate was 41.7% and 40.2%, respectively. Variables, including age at RT, primary site, type of tumor treated with RT, total radiation dose, and latency period did not have a significant effect on survival. The 5-year cause-specific and overall survival rate for patients who received treatment for R-OS involving

  18. PAI-1-Dependent Endothelial Cell Death Determines Severity of Radiation-Induced Intestinal Injury

    PubMed Central

    Abderrahmani, Rym; François, Agnes; Buard, Valerie; Tarlet, Georges; Blirando, Karl; Hneino, Mohammad; Vaurijoux, Aurelie; Benderitter, Marc; Sabourin, Jean-Christophe; Milliat, Fabien

    2012-01-01

    Normal tissue toxicity still remains a dose-limiting factor in clinical radiation therapy. Recently, plasminogen activator inhibitor type 1 (SERPINE1/PAI-1) was reported as an essential mediator of late radiation-induced intestinal injury. However, it is not clear whether PAI-1 plays a role in acute radiation-induced intestinal damage and we hypothesized that PAI-1 may play a role in the endothelium radiosensitivity. In vivo, in a model of radiation enteropathy in PAI-1 −/− mice, apoptosis of radiosensitive compartments, epithelial and microvascular endothelium was quantified. In vitro, the role of PAI-1 in the radiation-induced endothelial cells (ECs) death was investigated. The level of apoptotic ECs is lower in PAI-1 −/− compared with Wt mice after irradiation. This is associated with a conserved microvascular density and consequently with a better mucosal integrity in PAI-1 −/− mice. In vitro, irradiation rapidly stimulates PAI-1 expression in ECs and radiation sensitivity is increased in ECs that stably overexpress PAI-1, whereas PAI-1 knockdown increases EC survival after irradiation. Moreover, ECs prepared from PAI-1 −/− mice are more resistant to radiation-induced cell death than Wt ECs and this is associated with activation of the Akt pathway. This study demonstrates that PAI-1 plays a key role in radiation-induced EC death in the intestine and suggests that this contributes strongly to the progression of radiation-induced intestinal injury. PMID:22563394

  19. Pyruvate metabolism: A therapeutic opportunity in radiation-induced skin injury

    SciTech Connect

    Yoo, Hyun; Kang, Jeong Wook; Lee, Dong Won; Oh, Sang Ho; Lee, Yun-Sil; Lee, Eun-Jung; Cho, Jaeho

    2015-05-08

    Ionizing radiation is used to treat a range of cancers. Despite recent technological progress, radiation therapy can damage the skin at the administration site. The specific molecular mechanisms involved in this effect have not been fully characterized. In this study, the effects of pyruvate, on radiation-induced skin injury were investigated, including the role of the pyruvate dehydrogenase kinase 2 (PDK2) signaling pathway. Next generation sequencing (NGS) identified a wide range of gene expression differences between the control and irradiated mice, including reduced expression of PDK2. This was confirmed using Q-PCR. Cell culture studies demonstrated that PDK2 overexpression and a high cellular pyruvate concentration inhibited radiation-induced cytokine expression. Immunohistochemical studies demonstrated radiation-induced skin thickening and gene expression changes. Oral pyruvate treatment markedly downregulated radiation-induced changes in skin thickness and inflammatory cytokine expression. These findings indicated that regulation of the pyruvate metabolic pathway could provide an effective approach to the control of radiation-induced skin damage. - Highlights: • The effects of radiation on skin thickness in mice. • Next generation sequencing revealed that radiation inhibited pyruvate dehydrogenase kinase 2 expression. • PDK2 inhibited irradiation-induced cytokine gene expression. • Oral pyruvate treatment markedly downregulated radiation-induced changes in skin thickness.

  20. Effects of ceramide inhibition on radiation-induced apoptosis in human leukemia MOLT-4 cells.

    PubMed

    Takahashi, Eriko; Inanami, Osamu; Asanuma, Taketoshi; Kuwabara, Mikinori

    2006-03-01

    In the present study, using inhibitors of ceramide synthase (fumonisin B1), ketosphinganine synthetase (L-cycloserine), acid sphingomyelinase (D609 and desipramine) and neutral sphingomyelinase (GW4869), the role of ceramide in X-ray-induced apoptosis was investigated in MOLT-4 cells. The diacylglycerol kinase (DGK) assay showed that the intracellular concentration of ceramide increased time-dependently after X irradiation of cells, and this radiation-induced accumulation of ceramide did not occur prior to the appearance of apoptotic cells. Treatment with D609 significantly inhibited radiation-induced apoptosis, but did not inhibit the increase of intracellular ceramide. Treatment with desipramine or GW4869 prevented neither radiation-induced apoptosis nor the induced increase of ceramide. On the other hand, fumonisin B1 and L-cycloserine had no effect on the radiation-induced induction of apoptosis, in spite of significant inhibition of the radiation-induced ceramide. From these results, it was suggested that the increase of the intracellular concentration of ceramide was not essential for radiation-induced apoptosis in MOLT-4 cells.

  1. Synchrotron-Radiation Induced X-Ray Emission (SRIXE)

    SciTech Connect

    Jones, Keith W.

    1999-09-01

    and increase in scientific use can be maintained for the synchrotron x-ray source. A short summary of the present state of the synchrotron radiation-induced x-ray emission (SRIXE) method is presented here. Basically, SRIXE experiments can include any that depend on the detection. of characteristic x-rays produced by the incident x-ray beam born the synchrotron source as they interact with a sample. Thus, experiments done to measure elemental composition, chemical state, crystal, structure, and other sample parameters can be considered in a discussion of SRIXE. It is also clear that the experimentalist may well wish to use a variety of complementary techniques for study of a given sample. For this reason, discussion of computed microtomography (CMT) and x-ray diffraction is included here. It is hoped that this present discussion will serve as a succinct introduction to the basic ideas of SRIXE for those not working in the field and possibly help to stimulate new types of work by those starting in the field as well as by experienced practitioners of the art. The topics covered include short descriptions of (1) the properties of synchrotron radiation, (2) a description of facilities used for its production, (3) collimated microprobe, (4) focused microprobes, (5) continuum and monoenergetic excitation, (6) detection limits, (7) quantitation, (8) applications of SRIXE, (9) computed microtomography (CMT), and (10)chemical speciation using x-ray absorption near-edge structure (XANES) and extended x-ray absorption fine structure (EXAFS). An effort has been made to cite a wide variety of work from different laboratories to show the vital nature of the field.

  2. Image-based modeling of radiation-induced foci

    NASA Astrophysics Data System (ADS)

    Costes, Sylvain; Cucinotta, Francis A.; Ponomarev, Artem; Barcellos-Hoff, Mary Helen; Chen, James; Chou, William; Gascard, Philippe

    Several proteins involved in the response to DNA double strand breaks (DSB) form microscopically visible nuclear domains, or foci, after exposure to ionizing radiation. Radiation-induced foci (RIF) are believed to be located where DNA damage occurs. To test this assumption, we used Monte Carlo simulations to predict the spatial distribution of DSB in human nuclei exposed to high or low-LET radiation. We then compared these predictions to the distribution patterns of three DNA damage sensing proteins, i.e. 53BP1, phosphorylated ATM and γH2AX in human mammary epithelial. The probability to induce DSB can be derived from DNA fragment data measured experimentally by pulsed-field gel electrophoresis. We first used this probability in Monte Carlo simulations to predict DSB locations in synthetic nuclei geometrically described by a complete set of human chromosomes, taking into account microscope optics from real experiments. Simulations showed a very good agreement for high-LET, predicting 0.7 foci/µm along the path of a 1 GeV/amu Fe particle against measurement of 0.69 to 0.82 foci/µm for various RIF 5 min following exposure (LET 150 keV/µm). On the other hand, discrepancies were shown in foci frequency for low-LET, with measurements 20One drawback using a theoretical model for the nucleus is that it assumes a simplistic and static pattern for DNA densities. However DNA damage pattern is highly correlated to DNA density pattern (i.e. the more DNA, the more likely to have a break). Therefore, we generalized our Monte Carlo approach to real microscope images, assuming pixel intensity of DAPI in the nucleus was directly proportional to the amount of DNA in that pixel. With such approach we could predict DNA damage pattern in real images on a per nucleus basis. Since energy is randomly deposited along high-LET particle paths, RIF along these paths should also be randomly distributed. As expected, simulations produced DNA-weighted random (Poisson) distributions. In

  3. Radiation-Induced Liver Damage: Correlation of Histopathology with Hepatobiliary Magnetic Resonance Imaging, a Feasibility Study

    SciTech Connect

    Seidensticker, Max; Burak, Miroslaw; Kalinski, Thomas; Garlipp, Benjamin; Koelble, Konrad; Wust, Peter; Antweiler, Kai; Seidensticker, Ricarda; Mohnike, Konrad; Pech, Maciej; Ricke, Jens

    2015-02-15

    PurposeRadiotherapy of liver malignancies shows promising results (radioembolization, stereotactic irradiation, interstitial brachytherapy). Regardless of the route of application, a certain amount of nontumorous liver parenchyma will be collaterally damaged by radiation. The functional reserve may be significantly reduced with an impact on further treatment planning. Monitoring of radiation-induced liver damage by imaging is neither established nor validated. We performed an analysis to correlate the histopathological presence of radiation-induced liver damage with functional magnetic resonance imaging (MRI) utilizing hepatobiliary contrast media (Gd-BOPTA).MethodsPatients undergoing local high-dose-rate brachytherapy for whom a follow-up hepatobiliary MRI within 120 days after radiotherapy as well as an evaluable liver biopsy from radiation-exposed liver tissue within 7 days before MRI were retrospectively identified. Planning computed tomography (CT)/dosimetry was merged to the CT-documentation of the liver biopsy and to the MRI. Presence/absence of radiation-induced liver damage (histopathology) and Gd-BOPTA uptake (MRI) as well as the dose applied during brachytherapy at the site of tissue sampling was determined.ResultsFourteen biopsies from eight patients were evaluated. In all cases with histopathological evidence of radiation-induced liver damage (n = 11), no uptake of Gd-BOPTA was seen. In the remaining three, cases no radiation-induced liver damage but Gd-BOPTA uptake was seen. Presence of radiation-induced liver damage and absence of Gd-BOPTA uptake was correlated with a former high-dose exposition.ConclusionsAbsence of hepatobiliary MRI contrast media uptake in radiation-exposed liver parenchyma may indicate radiation-induced liver damage. Confirmatory studies are warranted.

  4. Recent advances in the management of brachial plexus injuries

    PubMed Central

    Bhandari, Prem Singh; Maurya, Sanjay

    2014-01-01

    Management of brachial plexus injury is a demanding field of hand and upper extremity surgery. With currently available microsurgical techniques, functional gains are rewarding in upper plexus injuries. However, treatment options in the management of flail and anaesthetic limb are still evolving. Last three decades have witnessed significant developments in the management of these injuries, which include a better understanding of the anatomy, advances in the diagnostic modalities, incorporation of intra-operative nerve stimulation techniques, more liberal use of nerve grafts in bridging nerve gaps, and the addition of new nerve transfers, which selectively neurotise the target muscles close to the motor end plates. Newer research works on the use of nerve allografts and immune modulators (FK 506) are under evaluation in further improving the results in nerve reconstruction. Direct reimplantation of avulsed spinal nerve roots into the spinal cord is another area of research in brachial plexus reconstruction. PMID:25190913

  5. Massive hemothorax: A rare complication after supraclavicular brachial plexus block

    PubMed Central

    Singh, Shiv Kumar; Katyal, Surabhi; Kumar, Amit; Kumar, Pawan

    2014-01-01

    Plexus block is the preferred anesthesia plan for upper limb surgeries. Among the known complications, hematoma formation following the vascular trauma is often occur but this complication is frequently underreported. We present a case where a massive hemothorax developed post operatively in a patient who underwent resection of giant cell tumor of the right hand radius bone followed by arthroplasty under brachial plexus block using supraclavicular approach. This case report attempts to highlight the essence of remaining vigilant postoperatively for first initial days after brachial plexus block, especially after failed or multiple attempts. Ultrasound guided technique in combination with nerve stimulator has proven to be more reliable and safer than traditional techniques. PMID:25886347

  6. Activating PTEN by COX-2 inhibitors antagonizes radiation-induced AKT activation contributing to radiosensitization

    SciTech Connect

    Meng, Zhen; Gan, Ye-Hua

    2015-05-01

    Radiotherapy is still one of the most effective nonsurgical treatments for many tumors. However, radioresistance remains a major impediment to radiotherapy. Although COX-2 inhibitors can induce radiosensitization, the underlying mechanism is not fully understood. In this study, we showed that COX-2 selective inhibitor celecoxib enhanced the radiation-induced inhibition of cell proliferation and apoptosis in HeLa and SACC-83 cells. Treatment with celecoxib alone dephosphorylated phosphatase and tensin homolog deleted on chromosome ten (PTEN), promoted PTEN membrane translocation or activation, and correspondingly dephosphorylated or inactivated protein kinase B (AKT). By contrast, treatment with radiation alone increased PTEN phosphorylation, inhibited PTEN membrane translocation and correspondingly activated AKT in the two cell lines. However, treatment with celecoxib or another COX-2 selective inhibitor (valdecoxib) completely blocked radiation-induced increase of PTEN phosphorylation, rescued radiation-induced decrease in PTEN membrane translocation, and correspondingly inactivated AKT. Moreover, celecoxib could also upregulate PTEN protein expression by downregulating Sp1 expression, thereby leading to the activation of PTEN transcription. Our results suggested that COX-2 inhibitors could enhance radiosensitization at least partially by activating PTEN to antagonize radiation-induced AKT activation. - Highlights: • COX-2 inhibitor, celecoxib, could enhance radiosensitization. • Radiation induced PTEN inactivation (phosphorylation) and AKT activation. • COX-2 inhibitor induced PTEN expression and activation, and inactivated AKT. • COX-2 inhibitor enhanced radiosensitization through activating PTEN.

  7. Ultrasonographic evaluation of brachial plexus tumors in five dogs.

    PubMed

    Rose, Scott; Long, Craig; Knipe, Marguerite; Hornof, Bill

    2005-01-01

    Five dogs with unilateral thoracic limb lameness, neurologic deficits, muscle atrophy, and pain, or a combination of these signs, were examined using ultrasonograghy. Large, hypoechoic tubular masses that displaced vessels and destroyed the normal architecture were found in each dog. The affected axilla of each patient was then imaged with computed tomography or magnetic resonance to fully assess the extent of the masses. We describe the use of ultrasound in screening patients for brachial plexus tumors.

  8. Brachial artery aneurysms associated with arteriovenous access for hemodialysis.

    PubMed

    Chemla, Eric; Nortley, Mei; Morsy, Mohamed

    2010-01-01

    Brachial artery aneurysm (BAA) is a rare condition. We describe a series of cases of BAA with arteriovenous access. Thirteen patients were retrospectively identified between January 2006 and July 2009 using a patient database. All were associated with brachio-cephalic fistulas. Mean age was 51.2 +/- 13.8 years. Twelve males (93.3%) were identified. Characteristics were: diabetes 1, hypertension 8, hypercholesterolemia 2, ischemic heart disease 2, family history of aneurysmal disease 2. Five BAA developed after access ligation, eight while it was working, one after trauma. One was associated with a venous aneurysm. While the average life of the access was 161 +/- 115 months, the average time for BAA formation was 40 +/- 35.8 months. BAA was asymptomatic in three patients, whereas 10 presented with ischemic and neurologic symptoms. None presented with a rupture. All patients underwent surgical repair, seven an aneurysm excision and end-to-end reconstruction of the brachial artery. Venous conduits were utilized: four long saphenous veins, one cephalic, and one basilic vein. All patients had patent brachial arteries with a complete relief of symptoms at 14 months. BAA is a rare but significant complication of vascular access. The surgical approaches presented offer a reasonable outcome.

  9. Evaluation of an education day for families of children with obstetrical brachial plexus palsy.

    PubMed

    Ho, Emily S; Ulster, Alissa A

    2011-09-01

    Children with obstetrical brachial plexus palsy may have chronic physical impairment in their affected upper extremity. Affected children and their families may benefit from psychosocial interventions including therapeutic relationships with health professionals, meeting other families living with obstetrical brachial plexus palsy, support groups, and social work. One method of addressing psychosocial needs is through a support and education day. The purpose of this quality improvement project is to evaluate parental perceptions of a support and education day called the "Brachial Plexus Family Day." Families of children with obstetrical brachial plexus palsy who attended the Brachial Plexus Family Day completed a questionnaire to evaluate the different programs offered during the day. The families also ranked the importance of different psychosocial supports offered in the clinic. Sixty-three out of 69 families completed the questionnaire. Each program of the Brachial Plexus Family Day was rated as good or excellent by the respondents. Ninety-seven percent of respondents rated meeting other families and children with obstetrical brachial plexus palsy as helpful supports. Attending a Brachial Plexus Family day event (86%), followed by connecting with a doctor (60%), and physical or occupational therapist (59%) were the highest ranked supports reported by the families. The parents and caregivers that attended the Brachial Plexus Family Day rated the program highly. This group also valued the opportunity to connect with other families and children affected with the same condition.

  10. Delayed rupture of a pseudoaneurysm in the brachial artery of a burn reconstruction patient

    PubMed Central

    2013-01-01

    A brachial artery pseudoaneurysm is a rare but serious condition that can be limb threatening. A number of reports have found that it may be the result of damage to the blood vessels around the brachial artery, either directly or indirectly, due to trauma or systemic diseases. We present our experience of delayed pseudoaneurysm rupture of the brachial artery in a rehabilitation patient with burns of the upper extremity who underwent fasciotomy and musculocutaneous flap coverage. We also provide a review of the brachial artery pseudoaneurysm. PMID:23758847

  11. [Modified grant method protocol for dissecting and identifying the brachial plexus].

    PubMed

    Arakawa, Takamitsu; Setsu, Tomiyoshi; Terashima, Toshio

    2004-03-01

    Dissection of the brachial plexus is an important part in the anatomical course, but it is difficult for medical students to identify individual nerves of the brachial plexus due to its complexity and numerous variations. We have recently adopted the Grant method (1991) to guide students in the successful identification of this plexus. However, according to the Grant method the part of the upper limb including the brachial plexus is dissected before the neck part, which makes it impossible to identify the roots, trunks, and cords of the brachial plexus, and to identify the nerve branches extending from the brachial plexus. Here, we propose of anatomical dissection protocol of the brachial plexus a modified Grant method for medical students and instructors. The points of the modified protocols are: (1) to dissect the brachial plexus after the dissection of the neck part, (2) to identify the nerve trunks at the scalenus gap after dissecting the lateral, medial and posterior cords. The modified Grant method can be adapted to any other dissecting protocol of the brachial plexus, and will allow students to cope with many variations of the brachial plexus when they occur.

  12. ATM Heterozygosity and the Development of Radiation-Induced Erectile Dysfunction and Urinary Morbidity Following Radiotherapy for Prostate Cancer

    DTIC Science & Technology

    2006-02-01

    mutation are more likely to develop radiation -induced complications . The principal goal of this project is to determine whether men who inherit a...W81XWH-04-1-0172 TITLE: ATM Heterozygosity and the Development of Radiation -Induced Erectile Dysfunction and Urinary Morbidity Following...SUBTITLE 5a. CONTRACT NUMBER ATM Heterozygosity and the Development of Radiation -Induced Erectile Dysfunction and Urinary Morbidity Following

  13. Radiation-induced trapped charge in metal-nitride-oxide-semiconductor structure

    SciTech Connect

    Takahashi, Y.; Ohnishi, K.; Fujimaki, T.; Yoshikawa, M.

    1999-12-01

    The radiation-induced trapped charge in insulation layer of metal-nitride-oxide-semiconductor (MNOS) structure has been investigated. The mechanism of charge trapping under irradiation is studied by the radiation-induced mid-gap voltage shift using a simple charge trap model. The depth profile of fixed charge in insulator before irradiation was evaluated by the mid-gap voltage of MNOS structures with varying insulator thicknesses using slanted etching method. The irradiation tests were carried out using Co-60 gamma ray source up to 1 Mrad(Si) with the gate voltage of +6 or {minus}6 V. The calculated results using the model can be fitted well to the experimental results, and the authors confirmed the model is very useful to discuss the radiation-induced trapped charge. By simulating the mid-gap voltage shift of MNOS structures, they considered the possibility for radiation hardened device.

  14. Attenuation of a radiation-induced conditioned taste aversion after the development of ethanol tolerance

    SciTech Connect

    Hunt, W.A.; Rabin, B.M.

    1988-01-01

    An attempt to reduce a radiation-induced conditioned taste aversion (CTA) was undertaken by rendering animals tolerant to ethanol. Ethanol tolerance, developed over 5 days, was sufficient to block a radiation-induced taste aversion, as well as an ethanol-induced CTA. Several intermittent doses of ethanol, which did not induce tolerance but removed the novelty of the conditioning stimulus, blocked an ethanol-induced CTA but not the radiation-induced CTA. A CTA induced by doses of radiation up to 500 rads was attenuated. These data suggest that radioprotection developing in association with ethanol tolerance is a result of a physiological response to the chronic presence of ethanol not to the ethanol itself.

  15. A molecular dynamics study of radiation induced diffusion in uranium dioxide

    NASA Astrophysics Data System (ADS)

    Martin, G.; Maillard, S.; Brutzel, L. Van; Garcia, P.; Dorado, B.; Valot, C.

    2009-03-01

    The nuclear oxide fuels are submitted 'in-pile' to strong structural and chemical modifications due to the fissions and temperature. The diffusion of species is notably the result of a thermal activation and of radiation induced diffusion. This study proposes to estimate to what extent the radiation induced diffusion contributes to the diffusion of lattice atoms in UO2. Irradiations are simulated using molecular dynamics simulation by displacement cascades induced by uranium primary knock-on atoms between 1 and 80 keV. As atoms are easier to displace when their vibration amplitude increases, the temperature range which have been investigated is 300-1400 K. Cascade overlaps were also simulated. The material is shown to melt at the end of cascades, yielding a reduced threshold energy displacement. The nuclear contribution to the radiation induced diffusion is compared to thermally activated diffusion under in-reactor and long-term storage conditions.

  16. Radiation-induced genomic instability and its implications for radiation carcinogenesis

    NASA Technical Reports Server (NTRS)

    Huang, Lei; Snyder, Andrew R.; Morgan, William F.

    2003-01-01

    Radiation-induced genomic instability is characterized by an increased rate of genetic alterations including cytogenetic rearrangements, mutations, gene amplifications, transformation and cell death in the progeny of irradiated cells multiple generations after the initial insult. Chromosomal rearrangements are the best-characterized end point of radiation-induced genomic instability, and many of the rearrangements described are similar to those found in human cancers. Chromosome breakage syndromes are defined by chromosome instability, and individuals with these diseases are cancer prone. Consequently, chromosomal instability as a phenotype may underlie some fraction of those changes leading to cancer. Here we attempt to relate current knowledge regarding radiation-induced chromosome instability with the emerging molecular information on the chromosome breakage syndromes. The goal is to understand how genetic and epigenetic factors might influence the onset of chromosome instability and the role of chromosomal instability in carcinogenesis.

  17. Survival and Margin Status in Head and Neck Radiation-Induced Sarcomas and De Novo Sarcomas.

    PubMed

    Rosko, Andrew J; Birkeland, Andrew C; Chinn, Steven B; Shuman, Andrew G; Prince, Mark E; Patel, Rajiv M; McHugh, Jonathan B; Spector, Matthew E

    2017-04-01

    Objective To describe histologic subtypes and oncologic outcomes among patients with radiation-induced and de novo sarcomas of the head and neck. Study Design Retrospective case series with chart review. Setting Tertiary academic center. Subject and Methods In total, 166 adult patients with sarcoma of the head and neck treated from January 1, 1985, to January 1, 2010, were included. Tumors were characterized as radiation induced (15.1%) vs de novo sarcomas (84.9%). Clinical and tumor characteristics were compared. The primary outcomes were overall survival (OS) and disease-specific survival (DSS). Results Radiation-induced sarcomas were more likely to be high grade ( P = .006) and advanced stage ( P = .03). Chondrosarcoma was more common in de novo tumors ( P = .02) while leiomyosarcoma ( P = .01), sarcoma not otherwise specified ( P = .02), and undifferentiated pleomorphic sarcoma ( P < .001) were more common in radiation-induced sarcomas. Radiation-induced sarcomas were associated with statistically significantly worse DSS ( P = .019) and OS ( P = .005) compared with de novo sarcomas, but when only high-grade soft tissue sarcomas were analyzed, neither DSS ( P = .48) nor OS ( P = .29) differed. Margin status was a significant predictor of survival as both R0 and R1 resections correlated with statistically better DSS and OS compared with R2 ( P < .001) resections and patients treated with radiation therapy/chemoradiation therapy alone ( P = .005). Conclusion Radiation-induced sarcomas of the head and neck correlate with worse survival compared with de novo tumors; however, when controlling for tumor grade and resection status, there is no statistically significant difference in observed outcomes.

  18. RhoA GTPase regulates radiation-induced alterations in endothelial cell adhesion and migration

    SciTech Connect

    Rousseau, Matthieu; Gaugler, Marie-Helene; Rodallec, Audrey; Bonnaud, Stephanie; Paris, Francois; Corre, Isabelle

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer We explore the role of RhoA in endothelial cell response to ionizing radiation. Black-Right-Pointing-Pointer RhoA is rapidly activated by single high-dose of radiation. Black-Right-Pointing-Pointer Radiation leads to RhoA/ROCK-dependent actin cytoskeleton remodeling. Black-Right-Pointing-Pointer Radiation-induced apoptosis does not require the RhoA/ROCK pathway. Black-Right-Pointing-Pointer Radiation-induced alteration of endothelial adhesion and migration requires RhoA/ROCK. -- Abstract: Endothelial cells of the microvasculature are major target of ionizing radiation, responsible of the radiation-induced vascular early dysfunctions. Molecular signaling pathways involved in endothelial responses to ionizing radiation, despite being increasingly investigated, still need precise characterization. Small GTPase RhoA and its effector ROCK are crucial signaling molecules involved in many endothelial cellular functions. Recent studies identified implication of RhoA/ROCK in radiation-induced increase in endothelial permeability but other endothelial functions altered by radiation might also require RhoA proteins. Human microvascular endothelial cells HMEC-1, either treated with Y-27632 (inhibitor of ROCK) or invalidated for RhoA by RNA interference were exposed to 15 Gy. We showed a rapid radiation-induced activation of RhoA, leading to a deep reorganisation of actin cytoskeleton with rapid formation of stress fibers. Endothelial early apoptosis induced by ionizing radiation was not affected by Y-27632 pre-treatment or RhoA depletion. Endothelial adhesion to fibronectin and formation of focal adhesions increased in response to radiation in a RhoA/ROCK-dependent manner. Consistent with its pro-adhesive role, ionizing radiation also decreased endothelial cells migration and RhoA was required for this inhibition. These results highlight the role of RhoA GTPase in ionizing radiation-induced deregulation of essential endothelial

  19. Compositional trends of radiation-induced effects in ternary systems of chalcogenide glasses

    NASA Astrophysics Data System (ADS)

    Kovalskiy, A.

    2003-01-01

    The effect of gamma-irradiation on the optical transmittance spectra of pseudobinary stoichiometric and non-stoichiometric cuts of ternary systems of chalcogenide glasses was studied. The application of chemical-bond approach is proposed to explain the features of compositional dependencies of radiation-induced effects in these materials. It is shown that free volume concept must be taken into consideration at the presence of different radiation-sensitive structural units. The creation processes of coordination defects connected with the formation of free volume and coupled with the capability of the constituent atoms to passivation are the main factors determining the magnitude of the radiation-induced effects in chalcogenide glasses.

  20. 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.

  1. Growth hormone used to control intractable bleeding caused by radiation-induced gastritis.

    PubMed

    Zhang, Liang; Xia, Wen-Jie; Zhang, Zheng-Sen; Lu, Xin-Liang

    2015-08-21

    Intractable bleeding caused by radiation-induced gastritis is rare. We describe a 69-year-old man with intractable hemorrhagic gastritis induced by postoperative radiotherapy for the treatment of esophageal carcinoma. Although anti-secretory therapy with or without octreotide was initiated for hemostasis over three months, melena still occurred off and on, and the patient required blood transfusions to maintain stable hemoglobin. Finally growth hormone was used in the treatment of hemorrhage for two weeks, and hemostasis was successfully achieved. This is the first report that growth hormone has been used to control intractable bleeding caused by radiation-induced gastritis.

  2. Antimicrobial fabric adsorbed iodine produced by radiation-induced graft polymerization

    NASA Astrophysics Data System (ADS)

    Aoki, Shoji; Fujiwara, Kunio; Sugo, Takanobu; Suzuki, Koichi

    2013-03-01

    Antimicrobial fabric was synthesized by radiation-induced graft polymerization of N-vinyl pyrrolidone onto polyolefine nonwoven fabric and subsequent adsorption of iodine. In response of the huge request for the antimicrobial material applied to face masks for swine flu in 2009, operation procedure of continuous radiation-induced graft polymerization apparatus was improved. The improved grafting production per week increased 3.8 times compared to the production by former operation procedure. Shipped antimicrobial fabric had reached 130,000 m2 from June until December, 2009.

  3. Non-Problematic Risks from Low-Dose Radiation-Induced DNA Damage Clusters

    PubMed Central

    Hayes, Daniel P.

    2008-01-01

    Radiation-induced DNA damage clusters have been proposed and are usually considered to pose the threat of serious biological damage. This has been attributed to DNA repair debilitation or cessation arising from the complexity of cluster damage. It will be shown here, contrary to both previous suggestions and perceived wisdom, that radiation induced damage clusters contribute to non-problematic risks in the low-dose, low-LET regime. The very complexity of cluster damage which inhibits and/or compromises DNA repair will ultimately be responsible for the elimination and/or diminution of precancer-ous and cancerous cells. PMID:18648573

  4. Late onset radiation-induced constrictive pericarditis and cardiomyopathy after radiotherapy

    PubMed Central

    Zhuang, Xiao-feng; Yang, Yan-min; Sun, Xiao-lu; Liao, Zhong-kai; Huang, Jie

    2017-01-01

    Abstract Introduction: Radiation-induced heart disease (RIHD) is a serious side effect of cancer treatment, including coronary artery disease, valvular cardiac dysfunction, cardiomyopathy, aortopathy, and chronic constrictive pericarditis. Herein, this case we present was diagnosed as radiation-induced constrictive pericarditis and cardiomyopathy by means of cardiac magnetic resonance (CMR) and transthoracic echocardiogram, finally confirmed by pathology after performing heart transplant operation. Conclusions: This case supports a notion that RIHD often causes multiple heart impairment and CMR is helpful to diagnose cardiomyopathy after radiation. PMID:28151876

  5. Gamma radiation-induced blue shift of resonance peaks of Bragg gratings in pure silica fibres

    SciTech Connect

    Faustov, A V; Mégret, P; Wuilpart, M; Kinet, D; Gusarov, A I; Zhukov, A V; Novikov, S G; Svetukhin, V V; Fotiadi, A A

    2016-02-28

    We report the first observation of a significant gamma radiation-induced blue shift of the reflection/transmission peak of fibre Bragg gratings inscribed into pure-silica core fibres via multiphoton absorption of femtosecond pulses. At a total dose of ∼100 kGy, the shift is ∼20 pm. The observed effect is attributable to the ionising radiation-induced decrease in the density of the silica glass when the rate of colour centre formation is slow. We present results of experimental measurements that provide the key parameters of the dynamics of the gratings for remote dosimetry and temperature sensing. (laser crystals and braggg ratings)

  6. New Methodology for First Principle Calculations of Electrical Levels for Radiation Induced Defects in Silicates

    DTIC Science & Technology

    2005-02-22

    GRANT NUMBER 4. TITLE AND SUBTITLE New Methodology For First Principle Calculations Of Electrical Levels For Radiation Induced Defects In Silicates ...materials, space materials, Silicon on Insulator ( SOI ) materials 16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON DONALD J SMITH

  7. Deep Friction Massage in Treatment of Radiation-induced Fibrosis: Rehabilitative Care for Breast Cancer Survivors

    PubMed Central

    Warpenburg, Mary J.

    2014-01-01

    Treatment for invasive breast cancer usually involves some combination of surgery, radiation therapy, chemotherapy, hormone therapy, and/or targeted therapy. For approximately 50% of patients, radiation therapy is a component of the therapies used. As a result, radiation-induced fibrosis is becoming a common and crippling side effect, leading to muscle imbalance with a lessened range of motion as well as pain and dysfunction of the vascular and lymphatic systems. No good estimates are available for how many patients experience complications from radiation. Radiation-induced fibrosis can affect the underlying fascia, muscles, organs, and bones within the primary target field and the larger secondary field that is caused by the scatter effect of radioactive elements. For breast cancer patients, the total radiation field may include the neck, shoulder, axillary, and thoracic muscles and the ribs for both the ipsilateral (cancer-affected) and contralateral sides. This case study indicates that therapy using deep friction massage can affect radiation-induced fibrosis beneficially, particularly in the thoracic muscles and the intercostals (ie, the muscles between the ribs). When delivered in intensive sessions using deep friction techniques, massage has the potential to break down fibrotic tissues, releasing the inflammation and free radicals that are caused by radiation therapy. In the course of the massage, painful and debilitating spasms resulting from fibrosis can be relieved and the progressive nature of the radiation-induced fibrosis interrupted. PMID:26770116

  8. Inactivation of Kupffer Cells by Gadolinium Chloride Protects Murine Liver From Radiation-Induced Apoptosis

    SciTech Connect

    Du Shisuo; Qiang Min; Zeng Zhaochong; Ke Aiwu; Ji Yuan; Zhang Zhengyu; Zeng Haiying; Liu Zhongshan

    2010-03-15

    Purpose: To determine whether the inhibition of Kupffer cells before radiotherapy (RT) would protect hepatocytes from radiation-induced apoptosis. Materials and Methods: A single 30-Gy fraction was administered to the upper abdomen of Sprague-Dawley rats. The Kupffer cell inhibitor gadolinium chloride (GdCl3; 10 mg/kg body weight) was intravenously injected 24 h before RT. The rats were divided into four groups: group 1, sham RT plus saline (control group); group 2, sham RT plus GdCl3; group 3, RT plus saline; and group 4, RT plus GdCl3. Liver tissue was collected for measurement of apoptotic cytokine expression and evaluation of radiation-induced liver toxicity by analysis of liver enzyme activities, hepatocyte micronucleus formation, apoptosis, and histologic staining. Results: The expression of interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha was significantly attenuated in group 4 compared with group 3 at 2, 6, 24, and 48 h after injection (p <0.05). At early points after RT, the rats in group 4 exhibited significantly lower levels of liver enzyme activity, apoptotic response, and hepatocyte micronucleus formation compared with those in group 3. Conclusion: Selective inactivation of Kupffer cells with GdCl3 reduced radiation-induced cytokine production and protected the liver against acute radiation-induced damage.

  9. In vivo evidence for an endothelium-dependent mechanism in radiation-induced normal tissue injury

    PubMed Central

    Rannou, Emilie; François, Agnès; Toullec, Aurore; Guipaud, Olivier; Buard, Valérie; Tarlet, Georges; Mintet, Elodie; Jaillet, Cyprien; Iruela-Arispe, Maria Luisa; Benderitter, Marc; Sabourin, Jean-Christophe; Milliat, Fabien

    2015-01-01

    The pathophysiological mechanism involved in side effects of radiation therapy, and especially the role of the endothelium remains unclear. Previous results showed that plasminogen activator inhibitor-type 1 (PAI-1) contributes to radiation-induced intestinal injury and suggested that this role could be driven by an endothelium-dependent mechanism. We investigated whether endothelial-specific PAI-1 deletion could affect radiation-induced intestinal injury. We created a mouse model with a specific deletion of PAI-1 in the endothelium (PAI-1KOendo) by a Cre-LoxP system. In a model of radiation enteropathy, survival and intestinal radiation injury were followed as well as intestinal gene transcriptional profile and inflammatory cells intestinal infiltration. Irradiated PAI-1KOendo mice exhibited increased survival, reduced acute enteritis severity and attenuated late fibrosis compared with irradiated PAI-1flx/flx mice. Double E-cadherin/TUNEL labeling confirmed a reduced epithelial cell apoptosis in irradiated PAI-1KOendo. High-throughput gene expression combined with bioinformatic analyses revealed a putative involvement of macrophages. We observed a decrease in CD68+cells in irradiated intestinal tissues from PAI-1KOendo mice as well as modifications associated with M1/M2 polarization. This work shows that PAI-1 plays a role in radiation-induced intestinal injury by an endothelium-dependent mechanism and demonstrates in vivo that the endothelium is directly involved in the progression of radiation-induced enteritis. PMID:26510580

  10. DETECTION OF LOW DOSE RADIATION INDUCED DNA DAMAGE USING TEMPERATURE DIFFERENTIAL FLUORESCENCE ASSAY

    EPA Science Inventory

    A rapid and sensitive fluorescence assay for radiation-induced DNA damage is reported. Changes in temperature-induced strand separation in both calf thymus DNA and plasmid DNA (puc 19 plasmid from Escherichia coli) were measured after exposure to low doses of radiation. Exposur...

  11. DETECTION OF LOW DOSE RADIATION INDUCED DNA DAMAGE USING TEMPERATURE DIFFERENNTIAL FLUORESENCE ASSAY

    EPA Science Inventory

    A rapid and sensitive fluorescence assay for radiation-induced DNA damage is reported. Changes in temperature-induced strand separation in both calf thymus DNA and plasmid DNA (puc 19 plasmid from Escherichia coli) were measured after exposure to low doses of radiation. Exposures...

  12. The radiation-induced changes in rectal mucosa: Hyperfractionated vs. hypofractionated preoperative radiation for rectal cancer

    SciTech Connect

    Starzewski, Jacek J.; Pajak, Jacek T.; Pawelczyk, Iwona; Lange, Dariusz; Golka, Dariusz . E-mail: dargolka@wp.pl; Brzeziska, Monika; Lorenc, Zbigniew

    2006-03-01

    Purpose: The purpose of the study was the qualitative and quantitative evaluation of acute radiation-induced rectal changes in patients who underwent preoperative radiotherapy according to two different irradiation protocols. Patients and Methods: Sixty-eight patients with rectal adenocarcinoma underwent preoperative radiotherapy; 44 and 24 patients underwent hyperfractionated and hypofractionated protocol, respectively. Fifteen patients treated with surgery alone served as a control group. Five basic histopathologic features (meganucleosis, inflammatory infiltrations, eosinophils, mucus secretion, and erosions) and two additional features (mitotic figures and architectural glandular abnormalities) of radiation-induced changes were qualified and quantified. Results: Acute radiation-induced reactions were found in 66 patients. The most common were eosinophilic and plasma-cell inflammatory infiltrations (65 patients), erosions, and decreased mucus secretion (54 patients). Meganucleosis and mitotic figures were more common in patients who underwent hyperfractionated radiotherapy. The least common were the glandular architectural distortions, especially in patients treated with hypofractionated radiotherapy. Statistically significant differences in morphologic parameters studied between groups treated with different irradiation protocols were found. Conclusion: The system of assessment is a valuable tool in the evaluation of radiation-induced changes in the rectal mucosa. A greater intensity of regenerative changes was found in patients treated with hyperfractionated radiotherapy.

  13. The Therapeutic Effect of Adipose-Derived Mesenchymal Stem Cells for Radiation-Induced Bladder Injury

    PubMed Central

    Qiu, Xuefeng; Zhang, Shiwei; Zhao, Xiaozhi; Fu, Kai; Guo, Hongqian

    2016-01-01

    This study was designed to investigate the protective effect of adipose derived mesenchymal stem cells (AdMSCs) against radiation-induced bladder injury (RIBI). Female rats were divided into 4 groups: (a) controls, consisting of nontreated rats; (b) radiation-treated rats; (c) radiation-treated rats receiving AdMSCs; and (d) radiation-treated rats receiving AdMSCs conditioned medium. AdMSCs or AdMSCs conditioned medium was injected into the muscular layer of bladder 24 h after radiation. Twelve weeks after radiation, urinary bladder tissue was collected for histological assessment and enzyme-linked immunosorbent assay (ELISA) after metabolic cage investigation. At the 1 w, 4 w, and 8 w time points following cells injection, 3 randomly selected rats in RC group and AdMSCs group were sacrificed to track injected AdMSCs. Metabolic cage investigation revealed that AdMSCs showed protective effect for radiation-induced bladder dysfunction. The histological and ELISA results indicated that the fibrosis and inflammation within the bladder were ameliorated by AdMSCs. AdMSCs conditioned medium showed similar effects in preventing radiation-induced bladder dysfunction. In addition, histological data indicated a time-dependent decrease in the number of AdMSCs in the bladder following injection. AdMSCs prevented radiation induced bladder dysfunction and histological changes. Paracrine effect might be involved in the protective effects of AdMSCs for RIBI. PMID:27051426

  14. 3D ultrasound Nakagami imaging for radiation-induced vaginal fibrosis

    NASA Astrophysics Data System (ADS)

    Yang, Xiaofeng; Rossi, Peter; Shelton, Joseph; Bruner, Debrorah; Tridandapani, Srini; Liu, Tian

    2014-03-01

    Radiation-induced vaginal fibrosis is a debilitating side-effect affecting up to 80% of women receiving radiotherapy for their gynecological (GYN) malignancies. Despite the significant incidence and severity, little research has been conducted to identify the pathophysiologic changes of vaginal toxicity. In a previous study, we have demonstrated that ultrasound Nakagami shape and PDF parameters can be used to quantify radiation-induced vaginal toxicity. These Nakagami parameters are derived from the statistics of ultrasound backscattered signals to capture the physical properties (e.g., arrangement and distribution) of the biological tissues. In this paper, we propose to expand this Nakagami imaging concept from 2D to 3D to fully characterize radiation-induced changes to the vaginal wall within the radiation treatment field. A pilot study with 5 post-radiotherapy GYN patients was conducted using a clinical ultrasound scanner (6 MHz) with a mechanical stepper. A serial of 2D ultrasound images, with radio-frequency (RF) signals, were acquired at 1 mm step size. The 2D Nakagami shape and PDF parameters were calculated from the RF signal envelope with a sliding window, and then 3D Nakagami parameter images were generated from the parallel 2D images. This imaging method may be useful as we try to monitor radiation-induced vaginal injury, and address vaginal toxicities and sexual dysfunction in women after radiotherapy for GYN malignancies.

  15. Pathophysiological Responses in Rat and Mouse Models of Radiation-Induced Brain Injury.

    PubMed

    Yang, Lianhong; Yang, Jianhua; Li, Guoqian; Li, Yi; Wu, Rong; Cheng, Jinping; Tang, Yamei

    2017-03-01

    The brain is the major dose-limiting organ in patients undergoing radiotherapy for assorted conditions. Radiation-induced brain injury is common and mainly occurs in patients receiving radiotherapy for malignant head and neck tumors, arteriovenous malformations, or lung cancer-derived brain metastases. Nevertheless, the underlying mechanisms of radiation-induced brain injury are largely unknown. Although many treatment strategies are employed for affected individuals, the effects remain suboptimal. Accordingly, animal models are extremely important for elucidating pathogenic radiation-associated mechanisms and for developing more efficacious therapies. So far, models employing various animal species with different radiation dosages and fractions have been introduced to investigate the prevention, mechanisms, early detection, and management of radiation-induced brain injury. However, these models all have limitations, and none are widely accepted. This review summarizes the animal models currently set forth for studies of radiation-induced brain injury, especially rat and mouse, as well as radiation dosages, dose fractionation, and secondary pathophysiological responses.

  16. Evolved Cellular Mechanisms to Respond to Genotoxic Insults: Implications for Radiation-Induced Hematologic Malignancies

    PubMed Central

    Fleenor, Courtney J.; Higa, Kelly; Weil, Michael M.; DeGregori, James

    2015-01-01

    Human exposure to ionizing radiation is highly associated with adverse health effects, including reduced hematopoietic cell function and increased risk of carcinogenesis. The hematopoietic deficits manifest across blood cell types and persist for years after radiation exposure, suggesting a long-lived and multi-potent cellular reservoir for radiation-induced effects. As such, research has focused on identifying both the immediate and latent hematopoietic stem cell responses to radiation exposure. Radiation-associated effects on hematopoietic function and malignancy development have generally been attributed to the direct induction of mutations resulting from radiation-induced DNA damage. Other studies have illuminated the role of cellular programs that both limit and enhance radiation-induced tissue phenotypes and carcinogenesis. In this review, distinct but collaborative cellular responses to genotoxic insults are highlighted, with an emphasis on how these programmed responses impact hematopoietic cellular fitness and competition. These radiation-induced cellular programs include apoptosis, senescence and impaired self-renewal within the hematopoietic stem cell (HSC) pool. In the context of sporadic DNA damage to a cell, these cellular responses act in concert to restore tissue function and prevent selection for adaptive oncogenic mutations. But in the contexts of whole-tissue exposure or whole-body exposure to genotoxins, such as radiotherapy or chemotherapy, we propose that these programs can contribute to long-lasting tissue impairment and increased carcinogenesis. PMID:26414506

  17. Impaired repair of ionizing radiation-induced DNA damage in Cockayne syndrome cells.

    PubMed

    Cramers, Patricia; Verhoeven, Esther E; Filon, A Ronald; Rockx, Davy A P; Santos, Susy J; van der Leer, Anneke A; Kleinjans, Jos C S; van Zeeland, Albert A; Mullenders, Leon H F

    2011-04-01

    Cockayne syndrome (CS) cells are defective in transcription-coupled repair (TCR) and sensitive to oxidizing agents, including ionizing radiation. We examined the hypothesis that TCR plays a role in ionizing radiation-induced oxidative DNA damage repair or alternatively that CS plays a role in transcription elongation after irradiation. Irradiation with doses up to 100 Gy did not inhibit RNA polymerase II-dependent transcription in normal and CS-B fibroblasts. In contrast, RNA polymerase I-dependent transcription was severely inhibited at 5 Gy in normal cells, indicating different mechanisms of transcription response to X rays. The frequency of radiation-induced base damage was 2 × 10(-7) lesions/base/Gy, implying that 150 Gy is required to induce one lesion/30-kb transcription unit; no TCR of X-ray-induced base damage in the p53 gene was observed. Therefore, it is highly unlikely that defective TCR underlies the sensitivity of CS to ionizing radiation. Overall genome repair levels of radiation-induced DNA damage measured by repair replication were significantly reduced in CS-A and CS-B cells. Taken together, the results do not provide evidence for a key role of TCR in repair of radiation-induced oxidative damages in human cells; rather, impaired repair of oxidative lesions throughout the genome may contribute to the CS phenotype.

  18. Molecular, Cellular and Functional Effects of Radiation-Induced Brain Injury: A Review

    PubMed Central

    Balentova, Sona; Adamkov, Marian

    2015-01-01

    Radiation therapy is the most effective non-surgical treatment of primary brain tumors and metastases. Preclinical studies have provided valuable insights into pathogenesis of radiation-induced injury to the central nervous system. Radiation-induced brain injury can damage neuronal, glial and vascular compartments of the brain and may lead to molecular, cellular and functional changes. Given its central role in memory and adult neurogenesis, the majority of studies have focused on the hippocampus. These findings suggested that hippocampal avoidance in cranial radiotherapy prevents radiation-induced cognitive impairment of patients. However, multiple rodent studies have shown that this problem is more complex. As the radiation-induced cognitive impairment reflects hippocampal and non-hippocampal compartments, it is of critical importance to investigate molecular, cellular and functional modifications in various brain regions as well as their integration at clinically relevant doses and schedules. We here provide a literature overview, including our previously published results, in order to support the translation of preclinical findings to clinical practice, and improve the physical and mental status of patients with brain tumors. PMID:26610477

  19. Neurogenic differentiation factor NeuroD confers protection against radiation-induced intestinal injury in mice

    PubMed Central

    Li, Ming; Du, Aonan; Xu, Jing; Ma, Yanchao; Cao, Han; Yang, Chao; Yang, Xiao-Dong; Xing, Chun-Gen; Chen, Ming; Zhu, Wei; Zhang, Shuyu; Cao, Jianping

    2016-01-01

    The gastrointestinal tract, especially the small intestine, is particularly sensitive to radiation, and is prone to radiation-induced injury as a result. Neurogenic differentiation factor (NeuroD) is an evolutionarily-conserved basic helix-loop-helix (bHLH) transcription factor. NeuroD contains a protein transduction domain (PTD), which allows it to be exogenously delivered across the membrane of mammalian cells, whereupon its transcription activity can be unleashed. Whether NeuroD has therapeutic effects for radiation-induced injury remains unclear. In the present study, we prepared a NeuroD-EGFP recombinant protein, and explored its protective effects on the survival and intestinal damage induced by ionizing radiation. Our results showed that NeuroD-EGFP could be transduced into small intestine epithelial cells and tissues. NeuroD-EGFP administration significantly increased overall survival of mice exposed to lethal total body irradiation (TBI). This recombinant NeuroD also reduced radiation-induced intestinal mucosal injury and apoptosis, and improved crypt survival. Expression profiling of NeuroD-EGFP-treated mice revealed upregulation of tissue inhibitor of metalloproteinase 1 (TIMP-1), a known inhibitor of apoptosis in mammalian cells. In conclusion, NeuroD confers protection against radiation-induced intestinal injury, and provides a novel therapeutic clinical option for the prevention of intestinal side effects of radiotherapy and the treatment of victims of incidental exposure. PMID:27436572

  20. A Nonhuman Primate Model of Human Radiation-Induced Venocclusive Liver Disease and Hepatocyte Injury

    SciTech Connect

    Yannam, Govardhana Rao; Han, Bing; Setoyama, Kentaro; Yamamoto, Toshiyuki; Ito, Ryotaro; Brooks, Jenna M.; Guzman-Lepe, Jorge; Galambos, Csaba; Fong, Jason V.; Deutsch, Melvin; Quader, Mubina A.; Yamanouchi, Kosho; Kabarriti, Rafi; Mehta, Keyur; Soto-Gutierrez, Alejandro; and others

    2014-02-01

    Background: Human liver has an unusual sensitivity to radiation that limits its use in cancer therapy or in preconditioning for hepatocyte transplantation. Because the characteristic veno-occlusive lesions of radiation-induced liver disease do not occur in rodents, there has been no experimental model to investigate the limits of safe radiation therapy or explore the pathogenesis of hepatic veno-occlusive disease. Methods and Materials: We performed a dose-escalation study in a primate, the cynomolgus monkey, using hypofractionated stereotactic body radiotherapy in 13 animals. Results: At doses ≥40 Gy, animals developed a systemic syndrome resembling human radiation-induced liver disease, consisting of decreased albumin, elevated alkaline phosphatase, loss of appetite, ascites, and normal bilirubin. Higher radiation doses were lethal, causing severe disease that required euthanasia approximately 10 weeks after radiation. Even at lower doses in which radiation-induced liver disease was mild or nonexistent, latent and significant injury to hepatocytes was demonstrated by asialoglycoprotein-mediated functional imaging. These monkeys developed hepatic failure with encephalopathy when they received parenteral nutrition containing high concentrations of glucose. Histologically, livers showed central obstruction via an unusual intimal swelling that progressed to central fibrosis. Conclusions: The cynomolgus monkey, as the first animal model of human veno-occlusive radiation-induced liver disease, provides a resource for characterizing the early changes and pathogenesis of venocclusion, for establishing nonlethal therapeutic dosages, and for examining experimental therapies to minimize radiation injury.

  1. Deep Friction Massage in Treatment of Radiation-induced Fibrosis: Rehabilitative Care for Breast Cancer Survivors.

    PubMed

    Warpenburg, Mary J

    2014-10-01

    Treatment for invasive breast cancer usually involves some combination of surgery, radiation therapy, chemotherapy, hormone therapy, and/or targeted therapy. For approximately 50% of patients, radiation therapy is a component of the therapies used. As a result, radiation-induced fibrosis is becoming a common and crippling side effect, leading to muscle imbalance with a lessened range of motion as well as pain and dysfunction of the vascular and lymphatic systems. No good estimates are available for how many patients experience complications from radiation. Radiation-induced fibrosis can affect the underlying fascia, muscles, organs, and bones within the primary target field and the larger secondary field that is caused by the scatter effect of radioactive elements. For breast cancer patients, the total radiation field may include the neck, shoulder, axillary, and thoracic muscles and the ribs for both the ipsilateral (cancer-affected) and contralateral sides. This case study indicates that therapy using deep friction massage can affect radiation-induced fibrosis beneficially, particularly in the thoracic muscles and the intercostals (ie, the muscles between the ribs). When delivered in intensive sessions using deep friction techniques, massage has the potential to break down fibrotic tissues, releasing the inflammation and free radicals that are caused by radiation therapy. In the course of the massage, painful and debilitating spasms resulting from fibrosis can be relieved and the progressive nature of the radiation-induced fibrosis interrupted.

  2. Radiation-induced meningioma after treatment for pituitary adenoma: Case report and literature review

    SciTech Connect

    Partington, M.D.; Davis, D.H. )

    1990-02-01

    Radiation-induced meningiomas are becoming increasingly well-recognized. We report a case of a 35-year-old man who developed a suprasellar meningioma 9 years after receiving a radiation dose of 4480 cGy for a pituitary adenoma. The literature is also reviewed. 10 references.

  3. Radiation induces genomic instability and mammary ductal dysplasia in Atm heterozygous mice

    NASA Technical Reports Server (NTRS)

    Weil, M. M.; Kittrell, F. S.; Yu, Y.; McCarthy, M.; Zabriskie, R. C.; Ullrich, R. L.

    2001-01-01

    Ataxia-telangiectasia (AT) is a genetic syndrome resulting from the inheritance of two defective copies of the ATM gene that includes among its stigmata radiosensitivity and cancer susceptibility. Epidemiological studies have demonstrated that although women with a single defective copy of ATM (AT heterozygotes) appear clinically normal, they may never the less have an increased relative risk of developing breast cancer. Whether they are at increased risk for radiation-induced breast cancer from medical exposures to ionizing radiation is unknown. We have used a murine model of AT to investigate the effect of a single defective Atm allele, the murine homologue of ATM, on the susceptibility of mammary epithelial cells to radiation-induced transformation. Here we report that mammary epithelial cells from irradiated mice with one copy of Atm truncated in the PI-3 kinase domain were susceptible to radiation-induced genomic instability and generated a 10% incidence of dysplastic mammary ducts when transplanted into syngenic recipients, whereas cells from Atm(+/+) mice were stable and formed only normal ducts. Since radiation-induced ductal dysplasia is a precursor to mammary cancer, the results indicate that AT heterozygosity increases susceptibility to radiogenic breast cancer in this murine model system.

  4. Radiation-induced conductivity and high-temperature Q changes in quartz resonators

    SciTech Connect

    Koehler, D R

    1981-01-01

    While high temperature electrolysis has proven beneficial as a technique to remove interstitial impurities from quartz, reliable indices to measure the efficacy of such a processing step are still under development. The present work is directed toward providing such an index. Two techniques have been investigated - one involves measurement of the radiation induced conductivity in quartz along the optic axis, and the second involves measurement of high temperature Q changes. Both effects originate when impurity charge compensators are released from their traps, in the first case resulting in ionic conduction and in the second case resulting in increased acoustic losses. Radiation induced conductivity measurements have been carried out with a 200 kV, 14 mA x-ray machine producing 5 rads/s. With electric fields of the order of 10/sup 4/ V/cm, the noise level in the current measuring system is equivalent to an ionic current generated by quartz impurities in the 1 ppB range. The accuracy of the high temperature ( 300 to 800/sup 0/K) Q/sup -1/ measurement technique will be determined. A number of resonators constructed of quartz material of different impurity contents have been tested and both the radiation induced conductivity and the high temperature Q/sup -1/ results compared with earlier radiation induced frequency and resonator resistance changes. 10 figures.

  5. A new CT-based method to quantify radiation-induced lung damage in patients.

    PubMed

    Ghobadi, Ghazaleh; Wiegman, Erwin M; Langendijk, Johannes A; Widder, Joachim; Coppes, Robert P; van Luijk, Peter

    2015-10-01

    A new method to assess radiation-induced lung toxicity (RILT) using CT-scans was developed. It is more sensitive in detecting damage and corresponds better to physician-rated radiation pneumonitis than routinely-used methods. Use of this method may improve lung toxicity assessment and thereby facilitate development of more accurate predictive models for RILT.

  6. A Prospective Cohort Study on Radiation-induced Hypothyroidism: Development of an NTCP Model

    SciTech Connect

    Boomsma, Marjolein J.; Bijl, Hendrik P.; Christianen, Miranda E.M.C.; Beetz, Ivo; Chouvalova, Olga; Steenbakkers, Roel J.H.M.; Laan, Bernard F.A.M. van der; Oosting, Sjoukje F.; Schilstra, Cornelis; Langendijk, Johannes A.

    2012-11-01

    Purpose: To establish a multivariate normal tissue complication probability (NTCP) model for radiation-induced hypothyroidism. Methods and Materials: The thyroid-stimulating hormone (TSH) level of 105 patients treated with (chemo-) radiation therapy for head-and-neck cancer was prospectively measured during a median follow-up of 2.5 years. Hypothyroidism was defined as elevated serum TSH with decreased or normal free thyroxin (T4). A multivariate logistic regression model with bootstrapping was used to determine the most important prognostic variables for radiation-induced hypothyroidism. Results: Thirty-five patients (33%) developed primary hypothyroidism within 2 years after radiation therapy. An NTCP model based on 2 variables, including the mean thyroid gland dose and the thyroid gland volume, was most predictive for radiation-induced hypothyroidism. NTCP values increased with higher mean thyroid gland dose (odds ratio [OR]: 1.064/Gy) and decreased with higher thyroid gland volume (OR: 0.826/cm{sup 3}). Model performance was good with an area under the curve (AUC) of 0.85. Conclusions: This is the first prospective study resulting in an NTCP model for radiation-induced hypothyroidism. The probability of hypothyroidism rises with increasing dose to the thyroid gland, whereas it reduces with increasing thyroid gland volume.

  7. Management of late radiation-induced rectal injury after treatment of carcinoma of the uterus

    SciTech Connect

    Allen-Mersh, T.G.; Wilson, E.J.; Hope-Stone, H.F.; Mann, C.V.

    1987-06-01

    Sixty-one of 1418 (4.3 per cent) patients treated with radiation for carcinoma of the uterus from 1963 to 1983 had significant radiation-induced complications of the intestine develop which required a surgical opinion considering further management. Ninety-three per cent of these complications involved the rectum. Florid proctitis resolved within two years of onset in 33 per cent of the patients who were managed conservatively while 22 per cent of the patients died of disseminated disease within the same time period. Surgical treatment was eventually necessary in 39 per cent of the patients who were initially treated conservatively for radiation induced proctitis. Rectal excision with coloanal sleeve anastomosis produced a satisfactory result in eight of 11 patients with severe radiation injury involving the rectum. The incidence of radiation-induced and malignant rectovaginal fistula were similar (1 per cent), but disease-induced symptoms tended to occur earlier after primary treatment (a median of eight months) compared with radiation-induced symptoms (a median of 16 months).

  8. Correlation between ultrasound imaging, cross-sectional anatomy, and histology of the brachial plexus: a review.

    PubMed

    van Geffen, Geert J; Moayeri, Nizar; Bruhn, Jörgen; Scheffer, Gert J; Chan, Vincent W; Groen, Gerbrand J

    2009-01-01

    The anatomy of the brachial plexus is complex. To facilitate the understanding of the ultrasound appearance of the brachial plexus, we present a review of important anatomic considerations. A detailed correlation of reconstructed, cross-sectional gross anatomy and histology with ultrasound sonoanatomy is provided.

  9. Prophylaxis and management of acute radiation-induced skin reactions: a systematic review of the literature

    PubMed Central

    Salvo, N.; Barnes, E.; van Draanen, J.; Stacey, E.; Mitera, G.; Breen, D.; Giotis, A.; Czarnota, G.; Pang, J.; De Angelis, C.

    2010-01-01

    Radiation therapy is a common treatment for cancer patients. One of the most common side effects of radiation is acute skin reaction (radiation dermatitis) that ranges from a mild rash to severe ulceration. Approximately 85% of patients treated with radiation therapy will experience a moderate-to-severe skin reaction. Acute radiation-induced skin reactions often lead to itching and pain, delays in treatment, and diminished aesthetic appearance—and subsequently to a decrease in quality of life. Surveys have demonstrated that a wide variety of topical, oral, and intravenous agents are used to prevent or to treat radiation-induced skin reactions. We conducted a literature review to identify trials that investigated products for the prophylaxis and management of acute radiation dermatitis. Thirty-nine studies met the pre-defined criteria, with thirty-three being categorized as prophylactic trials and six as management trials. For objective evaluation of skin reactions, the Radiation Therapy Oncology Group criteria and the U.S. National Cancer Institute Common Toxicity Criteria were the most commonly used tools (65% of the studies). Topical corticosteroid agents were found to significantly reduce the severity of skin reactions; however, the trials of corticosteroids evaluated various agents, and no clear indication about a preferred corticosteroid has emerged. Amifostine and oral enzymes were somewhat effective in preventing radiation-induced skin reactions in phase ii and phase iii trials respectively; further large randomized controlled trials should be undertaken to better investigate those products. Biafine cream (Ortho–McNeil Pharmaceuticals, Titusville, NJ, U.S.A.) was found not to be superior to standard regimes in the prevention of radiation-induced skin reactions (n = 6). In conclusion, the evidence is insufficient to support the use of a particular agent for the prevention and management of acute radiation-induced skin reactions. Future trials should focus

  10. Detecting Radiation-Induced Injury Using Rapid 3D Variogram Analysis of CT Images of Rat Lungs

    SciTech Connect

    Jacob, Rick E.; Murphy, Mark K.; Creim, Jeffrey A.; Carson, James P.

    2013-10-01

    A new heterogeneity analysis approach to discern radiation-induced lung damage was tested on CT images of irradiated rats. The method, combining octree decomposition with variogram analysis, demonstrated a significant correlation with radiation exposure levels, whereas conventional measurements and pulmonary function tests did not. The results suggest the new approach may be highly sensitive for assessing even subtle radiation-induced changes

  11. Finger movement at birth in brachial plexus birth palsy

    PubMed Central

    Nath, Rahul K; Benyahia, Mohamed; Somasundaram, Chandra

    2013-01-01

    AIM: To investigate whether the finger movement at birth is a better predictor of the brachial plexus birth injury. METHODS: We conducted a retrospective study reviewing pre-surgical records of 87 patients with residual obstetric brachial plexus palsy in study 1. Posterior subluxation of the humeral head (PHHA), and glenoid retroversion were measured from computed tomography or Magnetic resonance imaging, and correlated with the finger movement at birth. The study 2 consisted of 141 obstetric brachial plexus injury patients, who underwent primary surgeries and/or secondary surgery at the Texas Nerve and Paralysis Institute. Information regarding finger movement was obtained from the patient’s parent or guardian during the initial evaluation. RESULTS: Among 87 patients, 9 (10.3%) patients who lacked finger movement at birth had a PHHA > 40%, and glenoid retroversion < -12°, whereas only 1 patient (1.1%) with finger movement had a PHHA > 40%, and retroversion < -8° in study 1. The improvement in glenohumeral deformity (PHHA, 31.8% ± 14.3%; and glenoid retroversion 22.0° ± 15.0°) was significantly higher in patients, who have not had any primary surgeries and had finger movement at birth (group 1), when compared to those patients, who had primary surgeries (nerve and muscle surgeries), and lacked finger movement at birth (group 2), (PHHA 10.7% ± 15.8%; Version -8.0° ± 8.4°, P = 0.005 and P = 0.030, respectively) in study 2. No finger movement at birth was observed in 55% of the patients in this study group. CONCLUSION: Posterior subluxation and glenoid retroversion measurements indicated significantly severe shoulder deformities in children with finger movement at birth, in comparison with those lacked finger movement. However, the improvement after triangle tilt surgery was higher in patients who had finger movement at birth. PMID:23362472

  12. Postoperative analgesia comparing levobupivacaine and ropivacaine for brachial plexus block

    PubMed Central

    Watanabe, Kunitaro; Tokumine, Joho; Lefor, Alan Kawarai; Moriyama, Kumi; Sakamoto, Hideaki; Inoue, Tetsuo; Yorozu, Tomoko

    2017-01-01

    Abstract Background: On a pharmacologic basis, levobupivacaine is expected to last longer than ropivacaine. However, most reports of these anesthetics for brachial plexus block do not suggest a difference in analgesic effect. The aim of this study is to compare the postoperative analgesic effects of levobupivacaine and ropivacaine when used for treating ultrasound-guided brachial plexus block. Methods: A total of 62 patients undergoing orthopedic surgery procedures were prospectively enrolled and randomized to receive levobupivacaine (group L, N = 31) or ropivacaine (group R, N = 31). The duration of analgesia, offset time of motor block, need for rescue analgesics, and sleep disturbance on the night of surgery were recorded. Pain score was recorded on the day of surgery, and on postoperative days 1 and 2. Results: There was no difference in the time interval until the first request for pain medication comparing the two groups (group L: 15.6 [11.4, 16.8] hours; group R: 12.5 [9.4, 16.0] hours, P = 0.32). There was no difference in the duration of motor block (group L: 12.2 [7.6, 14.4] hours; group R: 9.4 [7.9, 13.2] hours, P = 0.44), pain score (P = 0.92), need for rescue analgesics (group L: 55%; group R: 65%, P = 0.6), or rate of sleep disturbance (group L: 61%, group R: 58%, P = 1.0) on comparing the two groups. Conclusions: There was no difference in postoperative analgesia comparing levobupivacaine and ropivacaine when used for brachial plexus block. PMID:28328862

  13. Dexamethasone added to lidocaine prolongs axillary brachial plexus blockade.

    PubMed

    Movafegh, Ali; Razazian, Mehran; Hajimaohamadi, Fatemeh; Meysamie, Alipasha

    2006-01-01

    Different additives have been used to prolong regional blockade. We designed a prospective, randomized, double-blind study to evaluate the effect of dexamethasone added to lidocaine on the onset and duration of axillary brachial plexus block. Sixty patients scheduled for elective hand and forearm surgery under axillary brachial plexus block were randomly allocated to receive either 34 mL lidocaine 1.5% with 2 mL of isotonic saline chloride (control group, n = 30) or 34 mL lidocaine 1.5% with 2 mL of dexamethasone (8 mg) (dexamethasone group, n = 30). Neither epinephrine nor bicarbonate was added to the treatment mixture. We used a nerve stimulator and multiple stimulations technique in all of the patients. After performance of the block, sensory and motor blockade of radial, median, musculocutaneous, and ulnar nerves were recorded at 5, 15, and 30 min. The onset time of the sensory and motor blockade was defined as the time between last injection and the total abolition of the pinprick response and complete paralysis. The duration of sensory and motor blocks were considered as the time interval between the administration of the local anesthetic and the first postoperative pain and complete recovery of motor functions. Sixteen patients were excluded because of unsuccessful blockade. The duration of surgery and the onset times of sensory and motor block were similar in the two groups. The duration of sensory (242 +/- 76 versus 98 +/- 33 min) and motor (310 +/- 81 versus 130 +/- 31 min) blockade were significantly longer in the dexamethasone than in the control group (P < 0.01). We conclude that the addition of dexamethasone to lidocaine 1.5% solution in axillary brachial plexus block prolongs the duration of sensory and motor blockade.

  14. Feasibility of OCT to detect radiation-induced esophageal damage in small animal models (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Jelvehgaran, Pouya; Alderliesten, Tanja; Salguero, Javier; Borst, Gerben; Song, Ji-Ying; van Leeuwen, Ton G.; de Boer, Johannes F.; de Bruin, Daniel M.; van Herk, Marcel B.

    2016-03-01

    Lung cancer survival is poor and radiotherapy patients often suffer serious treatment side effects. The esophagus is particularly sensitive leading to reduced food intake or even fistula formation. Only few direct techniques exist to measure radiation-induced esophageal damage, for which knowledge is needed to improve the balance between risk of tumor recurrence and complications. Optical coherence tomography (OCT) is a minimally-invasive imaging technique that obtains cross-sectional, high-resolution (1-10µm) images and is capable of scanning the esophageal wall up to 2-3mm depth. In this study we investigated the feasibility of OCT to detect esophageal radiation damage in mice. In total 30 mice were included in 4 study groups (1 main and 3 control groups). Mice underwent cone-beam CT imaging for initial setup assessment and dose planning followed by single-fraction dose delivery of 4, 10, 16, and 20Gy on 5mm spots, spaced 10mm apart. Mice were repeatedly imaged using OCT: pre-irradiation and up to 3 months post-irradiation. The control groups received either OCT only, irradiation only, or were sham-operated. We used histopathology as gold standard for radiation-induced damage diagnosis. The study showed edema in both the main and OCT-only groups. Furthermore, radiation-induced damage was primarily found in the highest dose region (distal esophagus). Based on the histopathology reports we were able to identify the radiation-induced damage in the OCT images as a change in tissue scattering related to the type of induced damage. This finding indicates the feasibility and thereby the potentially promising role of OCT in radiation-induced esophageal damage assessment.

  15. High resolution neurography of the brachial plexus by 3 Tesla magnetic resonance imaging.

    PubMed

    Cejas, C; Rollán, C; Michelin, G; Nogués, M

    2016-01-01

    The study of the structures that make up the brachial plexus has benefited particularly from the high resolution images provided by 3T magnetic resonance scanners. The brachial plexus can have mononeuropathies or polyneuropathies. The mononeuropathies include traumatic injuries and trapping, such as occurs in thoracic outlet syndrome due to cervical ribs, prominent transverse apophyses, or tumors. The polyneuropathies include inflammatory processes, in particular chronic inflammatory demyelinating polyneuropathy, Parsonage-Turner syndrome, granulomatous diseases, and radiation neuropathy. Vascular processes affecting the brachial plexus include diabetic polyneuropathy and the vasculitides. This article reviews the anatomy of the brachial plexus and describes the technique for magnetic resonance neurography and the most common pathologic conditions that can affect the brachial plexus.

  16. Acromioclavicular joint dislocation with associated brachial plexus injury

    PubMed Central

    Gallagher, Charles Alexander; Blakeney, William; Zellweger, René

    2014-01-01

    We present the case of a 32-year-old female who sustained a left acromioclavicular (AC) joint type V injury and brachial plexus injury. The patient's AC joint injury was identified 6 days after she was involved in a motorbike accident where she sustained multiple other injuries. She required operative fixation of the AC joint using a locking compression medial proximal tibial plate. At 3 months post operatively, the patient was found to have a subluxed left shoulder as a result of an axonal injury to the upper trunk of the brachial plexus. In addition, the tibial plate had cut out. The plate was subsequently removed. At 8 months the glenohumeral articulation had been restored and the patient had clinically regained significant shoulder function. After 15 months the patient was pain free and could complete all her activities of daily living without impediment. She returned to playing competitive pool after 24 months. PMID:24855076

  17. Modulation of radiation-induced apoptosis and G{sub 2}/M block in murine T-lymphoma cells

    SciTech Connect

    Palayoor, S.T.; Macklis, R.M.; Bump, E.A.; Coleman, C.N.

    1995-03-01

    Radiation-induced apoptosis in lymphocyte-derived cell lines is characterized by endonucleolytic cleavage of cellular DNA within hours after radiation exposure. We have studied this phenomenon qualitatively (DNA gel electrophoresis) and quantitatively (diphenylamine reagent assay) in murine EL4 T-lymphoma cells exposed to {sup 137}Cs {gamma} irradiation. Fragmentation was discernible within 18-24 h after exposure. It increased with time and dose and reached a plateau after 8 Gy of {gamma} radiation. We studied the effect of several pharmacological agents on the radiation-induced G{sub 2}/M block and DNA fragmentation. The agents which reduced the radiation-induced G{sub 2}/M-phase arrest (caffeine, theobromine, theophylline and 2-aminopurine) enhanced the degree of DNA fragmentation at 24 h. In contrast, the agents which sustained the radiation-induced G{sub 2}/M-phase arrest (TPA, DBcAMP, IBMX and 3-aminobenzamide) inhibited the DNA fragmentation at 24 h. These studies on EL4 lymphoma cells are consistent with the hypothesis that cells with radiation-induced genetic damage are eliminated by apoptosis subsequent to a G{sub 2}/M block. Furthermore, it may be possible to modulate the process of radiation-induced apoptosis in lymphoma cells with pharmacological agents that modify the radiation-induced G{sub 2}/M block, and to use this effect in the treatment of patients with malignant disease. 59 refs., 7 figs.

  18. Use of StarClose for brachial artery closure after percutaneous endovascular interventions.

    PubMed

    Puggioni, Alessandra; Boesmans, Evelyne; Deloose, Koen; Peeters, Patrick; Bosiers, Marc

    2008-01-01

    The objective of this study was to evaluate a percutaneous extravascular closure device (StarClose, Abbott Vascular, Redwood City, CA) after brachial endovascular approach. From 2004 to 2006, 29 patients received StarClose for brachial closure. Primary endpoints were successful deployment and absence of procedure-related morbidity, secondary endpoints were brachial artery patency on duplex and absence of late (> 30 days) complications. The device was successfully deployed in all patients. In two patients (6.8%) local complications occurred: one patient developed a large hematoma successfully treated with prolonged compression and a second patient presented with brachial artery occlusion requiring operative intervention. After a mean follow-up of 7.5+/-7.2 months, all patients had a palpable brachial/radial pulse; none had signs of infection, distal embolization or neurological deficits. On ultrasound b-mode imaging, the clip was visible as a 4 mm echolucent area at the outer anterior wall of the artery. Based on the peak systolic velocity ratios between the site of StarClose and proximal brachial artery (mean 1.08+/-0.2), none of the studied patients had a significant stenosis at the site of closure. StarClose is safe and effective in providing hemostasis following interventional procedures through the brachial artery; further advantages include patients comfort and early discharge.

  19. Reconstitution studies on the involvement of radiation-induced lipid peroxidation in damage to membrane enzymes.

    PubMed

    Yukawa, O; Nagatsuka, S; Nakazawa, T

    1983-04-01

    The effect of radiation on the drug-metabolizing enzyme system of microsomes, reconstituted with liposomes of microsomal phospholipids, NADPH-cytochrome P-450 reductase and cytochrome P-450, was examined to elucidate the role of lipid peroxidation of membranes in radiation-induced damage to membrane-bound enzymes. The reconstituted system of non-irradiated enzymes with irradiated liposomes showed a low activity of hexobarbital hydroxylation, whereas irradiated enzymes combined with non-irradiated liposomes exhibited an activity equal to that of unirradiated controls. Irradiation of liposomes caused a decrease in cytochrome P-450 content by destruction of the haem of cytochrome P-450 and also inhibited the binding capacity of cytochrome P-450 for hexobarbital. The relationship between radiation-induced lipid peroxidation and membrane-bound enzymes is discussed.

  20. Hyperbaric oxygen in the treatment of radiation-induced optic neuropathy

    SciTech Connect

    Guy, J.; Schatz, N.J.

    1986-08-01

    Four patients with radiation-induced optic neuropathies were treated with hyperbaric oxygen. They had received radiation therapy for treatment of pituitary tumors, reticulum cell sarcoma, and meningioma. Two presented with amaurosis fugax before the onset of unilateral visual loss and began hyperbaria within 72 hours after development of unilateral optic neuropathy. Both had return of visual function to baseline levels. The others initiated treatment two to six weeks after visual loss occurred in the second eye and had no significant improvement of vision. Treatment consisted of daily administration of 100% oxygen under 2.8 atmospheres of pressure for 14-28 days. There were no medical complications of hyperbaria. While hyperbaric oxygen is effective in the treatment of radiation-induced optic neuropathy, it must be instituted within several days of deterioration in vision for restoration of baseline function.

  1. Anti-apoptotic peptides protect against radiation-induced cell death.

    PubMed

    McConnell, Kevin W; Muenzer, Jared T; Chang, Kathy C; Davis, Chris G; McDunn, Jonathan E; Coopersmith, Craig M; Hilliard, Carolyn A; Hotchkiss, Richard S; Grigsby, Perry W; Hunt, Clayton R

    2007-04-06

    The risk of terrorist attacks utilizing either nuclear or radiological weapons has raised concerns about the current lack of effective radioprotectants. Here it is demonstrated that the BH4 peptide domain of the anti-apoptotic protein Bcl-xL can be delivered to cells by covalent attachment to the TAT peptide transduction domain (TAT-BH4) and provide protection in vitro and in vivo from radiation-induced apoptotic cell death. Isolated human lymphocytes treated with TAT-BH4 were protected against apoptosis following exposure to 15Gy radiation. In mice exposed to 5Gy radiation, TAT-BH4 treatment protected splenocytes and thymocytes from radiation-induced apoptotic cell death. Most importantly, in vivo radiation protection was observed in mice whether TAT-BH4 treatment was given prior to or after irradiation. Thus, by targeting steps within the apoptosis signaling pathway it is possible to develop post-exposure treatments to protect radio-sensitive tissues.

  2. Radiation induced darkening of the optical elements in the Startracker camera

    SciTech Connect

    White, R.H.; Wirtenson, G.R.

    1993-03-01

    Optical glass flats that closely simulate the elements used in the Startracker lens designs were exposed to doses of ionizing radiation ranging from 0.44 to 1300 krad. Photometer traces determined the transmittance of the samples as a function of both wavelength and dose for wavelengths in the range 300 to 1200 nm. Cerium stabilized glasses used in the radiation stabilized Startracker system showed only a small amount of darkening for doses up to and exceeding 1 Mrad. Glasses used in the unstabilized Startracker design showed significant darkening to visible and ultra-violet spectra for doses as low as 5 krad. Plots of transmittance versus wavelength for various doses are given for each of the Startracker optical elements. Radiation induced absorption parameters that determine the radiation induced absorption coefficient are tabulated and plotted versus wavelength.

  3. Radiation-induced 1/f noise degradation of bipolar linear voltage regulator

    NASA Astrophysics Data System (ADS)

    Qifeng, Zhao; Yiqi, Zhuang; Junlin, Bao; Wei, Hu

    2016-03-01

    Radiation-induced 1/f noise degradation in the LM117 bipolar linear voltage regulator is studied. Based on the radiation-induced degradation mechanism of the output voltage, it is suggested that the band-gap reference subcircuit is the critical component which leads to the 1/f noise degradation of the LM117. The radiation makes the base surface current of the bipolar junction transistors of the band-gap reference subcircuit increase, which leads to an increase in the output 1/f noise of the LM117. Compared to the output voltage, the 1/f noise parameter is more sensitive, it may be used to evaluate the radiation resistance capability of LM117. Project supported by the National Natural Science Foundation of China (Nos. 61076101, 61204092).

  4. Epigenetic regulation of diacylglycerol kinase alpha promotes radiation-induced fibrosis

    PubMed Central

    Weigel, Christoph; Veldwijk, Marlon R.; Oakes, Christopher C.; Seibold, Petra; Slynko, Alla; Liesenfeld, David B.; Rabionet, Mariona; Hanke, Sabrina A.; Wenz, Frederik; Sperk, Elena; Benner, Axel; Rösli, Christoph; Sandhoff, Roger; Assenov, Yassen; Plass, Christoph; Herskind, Carsten; Chang-Claude, Jenny; Schmezer, Peter; Popanda, Odilia

    2016-01-01

    Radiotherapy is a fundamental part of cancer treatment but its use is limited by the onset of late adverse effects in the normal tissue, especially radiation-induced fibrosis. Since the molecular causes for fibrosis are largely unknown, we analyse if epigenetic regulation might explain inter-individual differences in fibrosis risk. DNA methylation profiling of dermal fibroblasts obtained from breast cancer patients prior to irradiation identifies differences associated with fibrosis. One region is characterized as a differentially methylated enhancer of diacylglycerol kinase alpha (DGKA). Decreased DNA methylation at this enhancer enables recruitment of the profibrotic transcription factor early growth response 1 (EGR1) and facilitates radiation-induced DGKA transcription in cells from patients later developing fibrosis. Conversely, inhibition of DGKA has pronounced effects on diacylglycerol-mediated lipid homeostasis and reduces profibrotic fibroblast activation. Collectively, DGKA is an epigenetically deregulated kinase involved in radiation response and may serve as a marker and therapeutic target for personalized radiotherapy. PMID:26964756

  5. Spontaneous perseverative turning in rats with radiation-induced hippocampal damage

    SciTech Connect

    Mickley, G.A.; Ferguson, J.L.; Nemeth, T.J.; Mulvihill, M.A.; Alderks, C.E. )

    1989-08-01

    This study found a new behavioral correlate of lesions specific to the dentate granule cell layer of the hippocampus: spontaneous perseverative turning. Irradiation of a portion of the neonatal rat cerebral hemispheres produced hypoplasia of the granule cell layer of the hippocampal dentate gyrus while sparing the rest of the brain. Radiation-induced damage to the hippocampal formation caused rats placed in bowls to spontaneously turn in long, slow bouts without reversals. Irradiated subjects also exhibited other behaviors characteristic of hippocampal damage (e.g., perseveration in spontaneous exploration of the arms of a T-maze, retarded acquisition of a passive avoidance task, and increased horizontal locomotion). These data extend previously reported behavioral correlates of fascia dentata lesions and suggest the usefulness of a bout analysis of spontaneous bowl turning as a measure of nondiscrete-trial spontaneous alternation and a sensitive additional indicator of radiation-induced hippocampal damage.

  6. The potential influence of radiation-induced microenvironments in neoplastic progression

    NASA Technical Reports Server (NTRS)

    Barcellos-Hoff, M. H.; Chatterjee, A. (Principal Investigator)

    1998-01-01

    Ionizing radiation is a complete carcinogen, able both to initiate and promote neoplastic progression and is a known carcinogen of human and murine mammary gland. Tissue response to radiation is a composite of genetic damage, cell death and induction of new gene expression patterns. Although DNA damage is believed to initiate carcinogenesis, the contribution of these other aspects of radiation response are beginning to be explored. Our studies demonstrate that radiation elicits rapid and persistent global alterations in the mammary gland microenvironment. We postulate that radiation-induced microenvironments may affect epithelial cells neoplastic transformation by altering their number or susceptibility. Alternatively, radiation induced microenvironments may exert a selective force on initiated cells and/or be conducive to progression. A key impetus for these studies is the possibility that blocking these events could be a strategy to interrupt neoplastic progression.

  7. Tristetraprolin mediates radiation-induced TNF-α production in lung macrophages.

    PubMed

    Ray, Dipankar; Shukla, Shirish; Allam, Uday Sankar; Helman, Abigail; Ramanand, Susmita Gurjar; Tran, Linda; Bassetti, Michael; Krishnamurthy, Pranathi Meda; Rumschlag, Matthew; Paulsen, Michelle; Sun, Lei; Shanley, Thomas P; Ljungman, Mats; Nyati, Mukesh K; Zhang, Ming; Lawrence, Theodore S

    2013-01-01

    The efficacy of radiation therapy for lung cancer is limited by radiation-induced lung toxicity (RILT). Although tumor necrosis factor-alpha (TNF-α) signaling plays a critical role in RILT, the molecular regulators of radiation-induced TNF-α production remain unknown. We investigated the role of a major TNF-α regulator, Tristetraprolin (TTP), in radiation-induced TNF-α production by macrophages. For in vitro studies we irradiated (4 Gy) either a mouse lung macrophage cell line, MH-S or macrophages isolated from TTP knockout mice, and studied the effects of radiation on TTP and TNF-α levels. To study the in vivo relevance, mouse lungs were irradiated with a single dose (15 Gy) and assessed at varying times for TTP alterations. Irradiation of MH-S cells caused TTP to undergo an inhibitory phosphorylation at Ser-178 and proteasome-mediated degradation, which resulted in increased TNF-α mRNA stabilization and secretion. Similarly, MH-S cells treated with TTP siRNA or macrophages isolated from ttp (-/-) mice had higher basal levels of TNF-α, which was increased minimally after irradiation. Conversely, cells overexpressing TTP mutants defective in undergoing phosphorylation released significantly lower levels of TNF-α. Inhibition of p38, a known kinase for TTP, by either siRNA or a small molecule inhibitor abrogated radiation-induced TNF-α release by MH-S cells. Lung irradiation induced TTP(Ser178) phosphorylation and protein degradation and a simultaneous increase in TNF-α production in C57BL/6 mice starting 24 h post-radiation. In conclusion, irradiation of lung macrophages causes TTP inactivation via p38-mediated phosphorylation and proteasome-mediated degradation, leading to TNF-α production. These findings suggest that agents capable of blocking TTP phosphorylation or stabilizing TTP after irradiation could decrease RILT.

  8. Blockade of Kv1.3 channels ameliorates radiation-induced brain injury

    PubMed Central

    Peng, Ying; Lu, Kui; Li, Zichen; Zhao, Yaodong; Wang, Yiping; Hu, Bin; Xu, Pengfei; Shi, Xiaolei; Zhou, Bin; Pennington, Michael; Chandy, K. George; Tang, Yamei

    2014-01-01

    Background Tumors affecting the head, neck, and brain account for significant morbidity and mortality. The curative efficacy of radiotherapy for these tumors is well established, but radiation carries a significant risk of neurologic injury. So far, neuroprotective therapies for radiation-induced brain injury are still limited. In this study we demonstrate that Stichodactyla helianthus (ShK)–170, a specific inhibitor of the voltage-gated potassium (Kv)1.3 channel, protected mice from radiation-induced brain injury. Methods Mice were treated with ShK-170 for 3 days immediately after brain irradiation. Radiation-induced brain injury was assessed by MRI scans and a Morris water maze. Pathophysiological change of the brain was measured by immunofluorescence. Gene and protein expressions of Kv1.3 and inflammatory factors were measured by quantitative real-time PCR, reverse transcription PCR, ELISA assay, and western blot analyses. Kv currents were recorded in the whole-cell configuration of the patch-clamp technique. Results Radiation increased Kv1.3 mRNA and protein expression in microglia. Genetic silencing of Kv1.3 by specific short interference RNAs or pharmacological blockade with ShK-170 suppressed radiation-induced production of the proinflammatory factors interleukin-6, cyclooxygenase-2, and tumor necrosis factor–α by microglia. ShK-170 also inhibited neurotoxicity mediated by radiation-activated microglia and promoted neurogenesis by increasing the proliferation of neural progenitor cells. Conclusions The therapeutic effect of ShK-170 is mediated by suppression of microglial activation and microglia-mediated neurotoxicity and enhanced neurorestoration by promoting proliferation of neural progenitor cells. PMID:24305723

  9. Mitigating effect of EUK-207 on radiation-induced cognitive impairments.

    PubMed

    Raber, J; Davis, M J; Pfankuch, T; Rosenthal, R; Doctrow, S R; Moulder, J E

    2017-03-01

    The brain could be exposed to irradiation as part of a nuclear accident, radiological terrorism (dirty bomb scenario) or a medical radiological procedure. In the context of accidents or terrorism, there is considerable interest in compounds that can mitigate radiation-induced injury when treatment is initiated a day or more after the radiation exposure. As it will be challenging to determine the radiation exposure an individual has received within a relatively short time frame, it is also critical that the mitigating agent does not negatively affect individuals, including emergency workers, who might be treated, but who were not exposed. Alterations in hippocampus-dependent cognition often characterize radiation-induced cognitive injury. The catalytic ROS scavenger EUK-207 is a member of the class of metal-containing salen manganese (Mn) complexes that suppress oxidative stress, including in the mitochondria, and have been shown to mitigate radiation dermatitis, promote wound healing in irradiated skin, and mitigate vascular injuries in irradiated lungs. As the effects of EUK-207 against radiation injury in the brain are not known, we assessed the effects of EUK-207 on sham-irradiated animals and the ability of EUK-207 to mitigate radiation-induced cognitive injury. The day following irradiation or sham-irradiation, the mice started to receive EUK-207 and were cognitively tested 3 months following exposure. Mice irradiated at a dose of 15Gy showed cognitive impairments in the water maze probe trial. EUK-207 mitigated these impairments while not affecting cognitive performance of sham-irradiated mice in the water maze probe trial. Thus, EUK-207 has attractive properties and should be considered an ideal candidate to mitigate radiation-induced cognitive injury.

  10. Modification of polyethylene by radiation-induced graft polymerization of acrylic acid

    NASA Astrophysics Data System (ADS)

    Sidorova, L. P.; Aliev, A. D.; Zlobin, V. B.; Aliev, R. E.; Chalykh, A. E.; Kabanov, V. Ya.

    The kinetics investigation of the radiation-induced graft polymerization of acrylic acid onto low density polyethylene by direct method in aqueous solution in the presence of Mohr's salt, was performed. The technique of the contrasting of polyacrylic acid (PAA) graft layer was worked out by Ag +-ions. The structural and morphological peculiarities of grafted copolymers of PE with PAA were determined by the method of electron probe, and X-ray microanalysis by means of the electron microscopy.

  11. Radiation-induced conductivity and high temperature Q changes in quartz resonators

    SciTech Connect

    Koehler, D.R.

    1981-06-01

    While high temperature electrolysis has proven beneficial as a technique to remove interstitial impurities from quartz, reliable indices to measure the efficacy of such a processing step are still under development. The present work is directed toward providing such an index. Two techniques were investigated - one involves measurement of the radiation-induced conductivity in quartz along the optic axis, and the second involves measurement of high temperature Q changes. Both effects originate when impurity charge compensators are released from their traps, in the first case resulting in an associated increase in ionic conduction and in the second case resulting in increased acoustic losses. Radiation-induced conductivity measurements were carried out with a 200 kV, 14 mA X-ray machine producing approximately 5 rads/sec at the sample. With electric fields of the order of 10/sup 4/ V/cm, the noise level in the current measuring system is equivalent to an ionic current generated by quartz impurities in the 1 ppB range. The accuracy of the high temperature (300 to 800 K) Q/sup -1/ measurement technique is limited by the uncertainties associated with quantitative correlation of the high temperature acoustic losses with the concentration of impurity centers. A number of resonators constructed of quartz material of different impurity contents have been tested, and both the radiation-induced conductivity and the high temperature Q/sup -1/ results compared with earlier radiation-induced frequency and resonator resistance changes. A postirradiation-induced conductivity index and a high temperature Q index show excellent correlation with the earlier pulsed irradiation-induced dynamic resonator motional resistance changes, and it is therefore concluded that either measurement can be employed to serve as an acceptance criterion for radiation hardness.

  12. [Research advances in medical imaging for radiation-induced liver injury].

    PubMed

    Dong, Tian-ming; An, Ning-yu

    2013-12-01

    The applications of three dimensional conformal radiotherapy(3-DCRT)in the abdomen has been associated with the increased incidence of radiation-induced liver injury(RILI). Timely and appropriate evaluation of RILI is particularly important for the design and modification of clinical management of tumors. This article reviews the pathological and serological features of RILI, focusing on in the application of medical imaging.

  13. C-V and DLTS studies of radiation induced Si-SiO2 interface defects

    NASA Astrophysics Data System (ADS)

    Capan, I.; Janicki, V.; Jacimovic, R.; Pivac, B.

    2012-07-01

    Interface traps at the Si-SiO2 interface have been and will be an important performance limit in many (future) semiconductor devices. In this paper, we present a study of fast neutron radiation induced changes in the density of Si-SiO2 interface-related defects. Interface related defects (Pb centers) are detected before and upon the irradiation. The density of interface-related defects is increasing with the fast neutron fluence.

  14. Energy Distribution of Electrons in Radiation Induced-Helium Plasmas. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Lo, R. H.

    1972-01-01

    Energy distribution of high energy electrons as they slow down and thermalize in a gaseous medium is studied. The energy distribution in the entire energy range from source energies down is studied analytically. A helium medium in which primary electrons are created by the passage of heavy-charged particles from nuclear reactions is emphasized. A radiation-induced plasma is of interest in a variety of applications, such as radiation pumped lasers and gaseous core nuclear reactors.

  15. Effect of sodium meclofenamate on radiation-induced esophagitis and cystitis

    SciTech Connect

    Ambrus, J.L.; Ambrus, C.M.; Lillie, D.B.; Johnson, R.J.; Gastpar, H.; Kishel, S.

    1984-01-01

    Stumptailed monkeys (Macaca arctoides) received 2000 rad irradiation to the upper half of the esophagus and to the bladder by a 6-MeV linear accelerator. Endoscopy and biopsy was obtained from these organs weekly for 3 weeks. At the end of this period, the animals were autopsied and histopathologic examination undertaken. Sodium meclofenamate in doses of 5-20 mg/kg/day p.os was found effective in reducing or preventing radiation-induced esophagitis and cystitis.

  16. A selenocysteine derivative therapy affects radiation-induced pneumonitis in the mouse.

    PubMed

    Kunwar, Amit; Jain, V K; Priyadarsini, K I; Haston, Christina K

    2013-10-01

    The mechanism leading to the radiation-induced lung response of pneumonitis is largely unknown. Here we investigated whether treatment with 3,3'-diselenodipropionic acid (DSePA), which reduces radiation-induced oxidative stress in acute response models, decreases the lung response to irradiation. Mice of the C3H/HeJ (alveolitis/pneumonitis-responding) strain received 18 Gy whole-thorax irradiation, and a subset of these mice was treated with DSePA (2 mg/kg) three times per week, beginning at 2 hours after radiation treatment, and continuing in the postirradiation period until death because of respiratory distress symptoms. DSePA treatment increased the postirradiation survival time of mice by an average of 32 days (P = 0.0002). Radiation-treated and DSePA-treated mice presented lower levels of lipid peroxidation and augmented glutathione peroxidase in the lungs, compared with those levels measured in mice receiving radiation only, when mice receiving radiation only were killed because of distress symptoms, whereas catalase and superoxide dismutase levels did not show consistent differences among treatment groups. DSePA treatment decreased pneumonitis and the numbers of mast cells, neutrophils, and lymphocytes in the lungs and bronchoalveolar lavage, respectively, of irradiated mice relative to mice exposed to radiation alone. DSePA treatment also decreased the radiation-induced increase in granulocyte colony-stimulating factor levels in the bronchoalveolar lavage and lung-tissue expression of intercellular adhesion molecule-1 and E-selectin, while increasing the expression of glutathione peroxidase-4. We conclude that DSePA treatment reduces radiation-induced pneumonitis in mice by delaying oxidative damage and the inflammatory cell influx.

  17. Vitamin D Deficiency Is Associated With the Severity of Radiation-Induced Proctitis in Cancer Patients

    SciTech Connect

    Ghorbanzadeh-Moghaddam, Amir; Gholamrezaei, Ali; Hemati, Simin

    2015-07-01

    Purpose: Radiation-induced injury to normal tissues is a common complication of radiation therapy in cancer patients. Considering the role of vitamin D in mucosal barrier hemostasis and inflammatory responses, we investigated whether vitamin D deficiency is associated with the severity of radiation-induced acute proctitis in cancer patients. Methods and Materials: This prospective observational study was conducted in cancer patients referred for pelvic radiation therapy. Serum concentration of 25-hydroxyvitamin D was measured before radiation therapy. Vitamin D deficiency was defined as 25-hydroxyvitamin D concentrations of <35 nmol/L and <40 nmol/L in male and female patients, respectively, based on available normative data. Acute proctitis was assessed after 5 weeks of radiation therapy (total received radiation dose of 50 Gy) and graded from 0 to 4 using Radiation Therapy Oncology Group (RTOG) criteria. Results: Ninety-eight patients (57.1% male) with a mean age of 62.8 ± 9.1 years were studied. Vitamin D deficiency was found in 57 patients (58.1%). Symptoms of acute proctitis occurred in 72 patients (73.4%) after radiation therapy. RTOG grade was significantly higher in patients with vitamin D deficiency than in normal cases (median [interquartile range] of 2 [0.5-3] vs 1 [0-2], P=.037). Vitamin D deficiency was associated with RTOG grade of ≥2, independent of possible confounding factors; odds ratio (95% confidence interval) = 3.07 (1.27-7.50), P=.013. Conclusions: Vitamin D deficiency is associated with increased severity of radiation-induced acute proctitis. Investigating the underlying mechanisms of this association and evaluating the effectiveness of vitamin D therapy in preventing radiation-induced acute proctitis is warranted.

  18. Effects of subdiaphragmatic vagotomy on the acquisition of a radiation-induced conditioned taste aversion

    SciTech Connect

    Hunt, W.A.; Rabin, B.M.; Lee, J.

    1987-01-01

    The effect of subdiaphragmatic vagotomy on the acquisition of a radiation-induced taste aversion was examined to assess the importance of the vagus nerve in transmitting information on the peripheral toxicity of radiation to the brain. Vagotomy had no effect on taste aversion learning, consistent with reports using other toxins. The data support the involvement of a blood-borne factor in the acquisition of taste aversion induced by ionizing radiation.

  19. Study on chemical, UV and gamma radiation-induced grafting of 2-hydroxyethyl methacrylate onto chitosan

    NASA Astrophysics Data System (ADS)

    Casimiro, M. H.; Botelho, M. L.; Leal, J. P.; Gil, M. H.

    2005-04-01

    In the present study, 2-hydroxyethyl methacrylate has been grafted onto chitosan by using either chemical initiation, or photo-induction or gamma radiation-induced polymerisation, all under heterogeneous conditions. The evidence of grafting was provided by Fourier transform infrared spectroscopy and thermal analysis. The results concerning the effect of initiator concentration, initial monomer concentration and dose rate influencing on the yield of grafting reactions are presented. These suggest that gamma irradiation is the method that leads to higher yields of grafting.

  20. Hesperidin as Radioprotector against Radiation-induced Lung Damage in Rat: A Histopathological Study

    PubMed Central

    Haddadi, Gholam Hassan; Rezaeyan, Abolhasan; Mosleh-Shirazi, Mohammad Amin; Hosseinzadeh, Massood; Fardid, Reza; Najafi, Masoud; Salajegheh, Ashkan

    2017-01-01

    Reactive oxygen species (ROS) are generated by ionizing radiation, and one of the organs commonly affected by ROS is the lung. Radiation-induced lung injury including pneumonia and lung fibrosis is a dose-limiting factor in radiotherapy (RT) of patients with thorax irradiation. Administration of antioxidants has been proved to protect against ROS. The present study was aimed to assess the protective effect of hesperidin (HES) against radiation-induced lung injury of male rats. Fifty rats were divided into three groups. G1: Received no HES and radiation (sham). G2: Underwent γ-irradiation to the thorax. G3: Received HES and underwent γ-irradiation. The rats were exposed to a single dose of 18 Gy using cobalt-60 unit and were administered HES (100 mg/kg) for 7 days before irradiation. Histopathological analysis was performed 24 h and 8 weeks after RT. Histopathological results in 24 h showed radiation-induced inflammation and presence of more inflammatory cells as compared to G1 (P < 0.05). Administration of HES significantly decreased such an effect when compared to G2 (P < 0.05). Histopathological evaluation in 8 weeks showed a significant increase in mast cells, inflammation, inflammatory cells, alveolar thickness, vascular thickness, pulmonary edema, and fibrosis in G2 when compared to G1 (P < 0.05). HES significantly decreased inflammatory response, fibrosis, and mast cells when compared to G2 (P < 0.05). Administration of HES resulted in decreased radiation pneumonitis and radiation fibrosis in the lung tissue. Thus, the present study showed HES to be an efficient radioprotector against radiation-induced damage in the lung of tissue rats.

  1. Impact of p53 status on heavy-ion radiation-induced micronuclei in circulating erythrocytes

    NASA Technical Reports Server (NTRS)

    Chang, P. Y.; Torous, D.; Lutze-Mann, L.; Winegar, R.

    2000-01-01

    Transgenic mice that differed in their p53 genetic status were exposed to an acute dose of highly charged and energetic (HZE) iron particle radiation. Micronuclei (MN) in two distinct populations of circulating peripheral blood erythrocytes, the immature reticulocytes (RETs) and the mature normochromatic erythrocytes (NCEs), were measured using a simple and efficient flow cytometric procedure. Our results show significant elevation in the frequency of micronucleated RETs (%MN-RETs) at 2 and 3 days post-radiation. At 3 days post-irradiation, the magnitude of the radiation-induced MN-RET was 2.3-fold higher in the irradiated p53 wild-type animals compared to the unirradiated controls, 2.5-fold higher in the p53 hemizygotes and 4.3-fold higher in the p53 nullizygotes. The persistence of this radiation-induced elevation of MN-RETs is dependent on the p53 genetic background of the animal. In the p53 wild-type and p53 hemizygotes, %MN-RETs returned to control levels by 9 days post-radiation. However, elevated levels of %MN-RETs in p53 nullizygous mice persisted beyond 56 days post-radiation. We also observed elevated MN-NCEs in the peripheral circulation after radiation, but the changes in radiation-induced levels of MN-NCEs appear dampened compared to those of the MN-RETs for all three strains of animals. These results suggest that the lack of p53 gene function may play a role in the iron particle radiation-induced genomic instability in stem cell populations in the hematopoietic system.

  2. Amelioration of radiation-induced hematopoietic and gastrointestinal damage by Ex-RAD(R) in mice.

    PubMed

    Ghosh, Sanchita P; Kulkarni, Shilpa; Perkins, Michael W; Hieber, Kevin; Pessu, Roli L; Gambles, Kristen; Maniar, Manoj; Kao, Tzu-Cheg; Seed, Thomas M; Kumar, K Sree

    2012-07-01

    The aim of the present study was to assess recovery from hematopoietic and gastrointestinal damage by Ex-RAD(®), also known as ON01210.Na (4-carboxystyryl-4-chlorobenzylsulfone, sodium salt), after total body radiation. In our previous study, we reported that Ex-RAD, a small-molecule radioprotectant, enhances survival of mice exposed to gamma radiation, and prevents radiation-induced apoptosis as measured by the inhibition of radiation-induced protein 53 (p53) expression in cultured cells. We have expanded this study to determine best effective dose, dose-reduction factor (DRF), hematological and gastrointestinal protection, and in vivo inhibition of p53 signaling. A total of 500 mg/kg of Ex-RAD administered at 24 h and 15 min before radiation resulted in a DRF of 1.16. Ex-RAD ameliorated radiation-induced hematopoietic damage as monitored by the accelerated recovery of peripheral blood cells, and protection of granulocyte macrophage colony-forming units (GM-CFU) in bone marrow. Western blot analysis on spleen indicated that Ex-RAD treatment inhibited p53 phosphorylation. Ex-RAD treatment reduces terminal deoxynucleotidyl transferase mediated dUTP nick end labeling assay (TUNEL)-positive cells in jejunum compared with vehicle-treated mice after radiation injury. Finally, Ex-RAD preserved intestinal crypt cells compared with the vehicle control at 13 and 14 Gy. The results demonstrated that Ex-RAD ameliorates radiation-induced peripheral blood cell depletion, promotes bone marrow recovery, reduces p53 signaling in spleen and protects intestine from radiation injury.

  3. Selenoprotein P Inhibits Radiation-Induced Late Reactive Oxygen Species Accumulation and Normal Cell Injury

    SciTech Connect

    Eckers, Jaimee C.; Kalen, Amanda L.; Xiao, Wusheng; Sarsour, Ehab H.; Goswami, Prabhat C.

    2013-11-01

    Purpose: Radiation is a common mode of cancer therapy whose outcome is often limited because of normal tissue toxicity. We have shown previously that the accumulation of radiation-induced late reactive oxygen species (ROS) precedes cell death, suggesting that metabolic oxidative stress could regulate cellular radiation response. The purpose of this study was to investigate whether selenoprotein P (SEPP1), a major supplier of selenium to tissues and an antioxidant, regulates late ROS accumulation and toxicity in irradiated normal human fibroblasts (NHFs). Methods and Materials: Flow cytometry analysis of cell viability, cell cycle phase distribution, and dihydroethidium oxidation, along with clonogenic assays, were used to measure oxidative stress and toxicity. Human antioxidant mechanisms array and quantitative real-time polymerase chain reaction assays were used to measure gene expression during late ROS accumulation in irradiated NHFs. Sodium selenite addition and SEPP1 overexpression were used to determine the causality of SEPP1 regulating late ROS accumulation and toxicity in irradiated NHFs. Results: Irradiated NHFs showed late ROS accumulation (4.5-fold increase from control; P<.05) that occurs after activation of the cell cycle checkpoint pathways and precedes cell death. The mRNA levels of CuZn- and Mn-superoxide dismutase, catalase, peroxiredoxin 3, and thioredoxin reductase 1 increased approximately 2- to 3-fold, whereas mRNA levels of cold shock domain containing E1 and SEPP1 increased more than 6-fold (P<.05). The addition of sodium selenite before the radiation treatment suppressed toxicity (45%; P<.05). SEPP1 overexpression suppressed radiation-induced late ROS accumulation (35%; P<.05) and protected NHFs from radiation-induced toxicity (58%; P<.05). Conclusion: SEPP1 mitigates radiation-induced late ROS accumulation and normal cell injury.

  4. Radiatively induced Lorentz-violating operator of mass dimension five in QED

    SciTech Connect

    Mariz, T.

    2011-02-15

    The first higher derivative term of the photon sector of Lorentz-violating QED, with an operator of mass dimension d=5, is radiatively induced from the fermion sector, which contains a derivative term with the dimensionless coefficient g{sup {lambda}{mu}{nu}}. The calculation is performed perturbatively in the coefficient for Lorentz violation, and, due to the fact that the contributions are quadratically divergent, we adopt dimensional regularization.

  5. Radiation-induced alterations in histone modification patterns and their potential impact on short-term radiation effects

    PubMed Central

    Friedl, Anna A.; Mazurek, Belinda; Seiler, Doris M.

    2012-01-01

    Detection and repair of radiation-induced DNA damage occur in the context of chromatin. An intricate network of mechanisms defines chromatin structure, including DNA methylation, incorporation of histone variants, histone modifications, and chromatin remodeling. In the last years it became clear that the cellular response to radiation-induced DNA damage involves all of these mechanisms. Here we focus on the current knowledge on radiation-induced alterations in post-translational histone modification patterns and their effect on the chromatin accessibility, transcriptional regulation and chromosomal stability. PMID:23050241

  6. Avulsion of the brachial plexus in a great horned owl (Bubo virginaus)

    USGS Publications Warehouse

    Moore, M.P.; Stauber, E.; Thomas, N.J.

    1989-01-01

    Avulsion of the brachial plexus was documented in a Great Horned Owl (Bubo virginianus). A fractured scapula was also present. Cause of these injuries was not known but was thought to be due to trauma. Differentiation of musculoskeletal injury from peripheral nerve damage can be difficult in raptors. Use of electromyography and motor nerve conduction velocity was helpful in demonstrating peripheral nerve involvement. A brachial plexus avulsion was suspected on the basis of clinical signs, presence of electromyographic abnormalities in all muscles supplied by the nerves of the brachial plexus and absence of median-ulnar motor nerve conduction velocities.

  7. Lessons learned using different mouse models during space radiation-induced lung tumorigenesis experiments.

    PubMed

    Wang, Jian; Zhang, Xiangming; Wang, Ping; Wang, Xiang; Farris, Alton B; Wang, Ya

    2016-06-01

    Unlike terrestrial ionizing radiation, space radiation, especially galactic cosmic rays (GCR), contains high energy charged (HZE) particles with high linear energy transfer (LET). Due to a lack of epidemiologic data for high-LET radiation exposure, it is highly uncertain how high the carcinogenesis risk is for astronauts following exposure to space radiation during space missions. Therefore, using mouse models is necessary to evaluate the risk of space radiation-induced tumorigenesis; however, which mouse model is better for these studies remains uncertain. Since lung tumorigenesis is the leading cause of cancer death among both men and women, and low-LET radiation exposure increases human lung carcinogenesis, evaluating space radiation-induced lung tumorigenesis is critical to enable safe Mars missions. Here, by comparing lung tumorigenesis obtained from different mouse strains, as well as miR-21 in lung tissue/tumors and serum, we believe that wild type mice with a low spontaneous tumorigenesis background are ideal for evaluating the risk of space radiation-induced lung tumorigenesis, and circulating miR-21 from such mice model might be used as a biomarker for predicting the risk.

  8. Effects of NOX1 on fibroblastic changes of endothelial cells in radiation-induced pulmonary fibrosis

    PubMed Central

    CHOI, SEO-HYUN; KIM, MISEON; LEE, HAE-JUNE; KIM, EUN-HO; KIM, CHUN-HO; LEE, YOON-JIN

    2016-01-01

    Lung fibrosis is a major complication in radiation-induced lung damage following thoracic radiotherapy, while the underlying mechanism has remained to be elucidated. The present study performed immunofluorescence and immunoblot assays on irradiated human pulmonary artery endothelial cells (HPAECs) with or without pre-treatment with VAS2870, a novel NADPH oxidase (NOX) inhibitor, or small hairpin (sh)RNA against NOX1, -2 or -4. VAS2870 reduced the cellular reactive oxygen species content induced by 5 Gy radiation in HPAECs and inhibited phenotypic changes in fibrotic cells, including increased alpha smooth muscle actin and vimentin, and decreased CD31 and vascular endothelial cadherin expression. These fibrotic changes were significantly inhibited by treatment with NOX1 shRNA, but not by NOX2 or NOX4 shRNA. Next, the role of NOX1 in pulmonary fibrosis development was assessed in the lung tissues of C57BL/6J mice following thoracic irradiation using trichrome staining. Administration of an NOX1-specific inhibitor suppressed radiation-induced collagen deposition and fibroblastic changes in the endothelial cells (ECs) of these mice. The results suggested that radiation-induced pulmonary fibrosis may be efficiently reduced by specific inhibition of NOX1, an effect mediated by reduction of fibrotic changes of ECs. PMID:27053172

  9. Protective effects of caffeic acid phenethyl ester against acute radiation-induced hepatic injury in rats.

    PubMed

    Chu, JianJun; Zhang, Xiaojun; Jin, Liugen; Chen, Junliang; Du, Bin; Pang, Qingfeng

    2015-03-01

    Caffeic acid phenyl ester (CAPE) is a potent anti-inflammatory agent and it can eliminate the free radicals. The current study was intended to evaluate the protective effect of CAPE against the acute radiation-induced liver damage in rats. Male Sprague-Dawley rats were intraperitoneally administered with CAPE (30 mg/kg) for 3 consecutive days before exposing them to a single dose of 30 Gy of β-ray irradiation to upper abdomen. We found that pretreatment with CAPE significantly decreased the serum levels of alanine aminotransferase and aspartate aminotransferase and increased the activity of superoxide dismutase and glutathione. Histological evaluation further confirmed the protection of CAPE against radiation-induced hepatotoxicity. TUNEL assay showed that CAPE pretreatment inhibited hepatocyte apoptosis. Moreover, CAPE inhibited the nuclear transport of NF-κB p65 subunit, decreased the level of tumor necrosis factor-α, nitric oxide and inducible nitric oxide synthase. Taken together, these results suggest that pretreatment with CAPE offers protection against radiation-induced hepatic injury.

  10. Role of the area postrema in radiation-induced taste aversion learning and emesis in cats

    SciTech Connect

    Rabin, B.M.; Hunt, W.A.; Chedester, A.L.; Lee, J.

    1986-01-01

    The role of the area postrema in radiation-induced emesis and taste aversion learning and the relationship between these behaviors were studied in cats. The potential involvement of neural factors which might be independent of the area postrema was minimized by using low levels of ionizing radiation (100 rads at a dose rate of 40 rads/min) to elicit a taste aversion, and by using body-only exposures (4500 and 6000 rads at 450 rads/min) to produce emesis. Lesions of the area postrema disrupted both taste aversion learning and emesis following irradiation. These results, which indicate that the area postrema is involved in the mediation of both radiation-induced emesis and taste aversion learning in cats under these experimental conditions, are interpreted as being consistent with the hypotheses that similar mechanisms mediate both responses to exposure to ionizing radiation, and that the taste aversion learning paradigm can therefore serve as a model system for studying radiation-induced emesis.

  11. Altered gastric emptying and prevention of radiation-induced vomiting in dogs. [Cobalt 60 irradiation

    SciTech Connect

    Dubois, A.; Jacobus, J.P.; Grissom, M.P.; Eng, R.R.; Conklin, J.J.

    1984-03-01

    The relation between radiation-induced vomiting and gastric emptying is unclear and the treatment of this condition is not established. We explored, therefore, (a) the effect of cobalt 60 irradiation on gastric emptying of solids and liquids and (b) the possibility of preventing radiation-induced vomiting with the dopamine antagonist, domperidone. Twenty dogs were studied on two separate days, blindly and in random order, after i.v. injection of either a placebo or 0.06 mg/kg domperidone. On a third day, they received 8 Gy (800 rads) whole body irradiation with cobalt 60 gamma-rays after either placebo (n . 10) or domperidone (n . 10). Before each study, each dog was fed chicken liver tagged in vivo with 99mTc-sulfur colloid (solid marker), and water containing 111In-diethylenetriamine pentaacetic acid (liquid marker). Dogs were placed in a Pavlov stand for the subsequent 3 h and radionuclide imaging was performed at 10-min intervals. Irradiation produced vomiting in 9 of 10 dogs given placebo but only in 1 of 10 dogs pretreated with domperidone (p less than 0.01). Gastric emptying of liquids and solids was significantly suppressed by irradiation (p less than 0.01) after both placebo and domperidone. These results demonstrate that radiation-induced vomiting is accompanied by suppression of gastric emptying. Furthermore, domperidone prevents vomiting produced by ionizing radiation but does not alter the accompanying delay of gastric emptying.

  12. Mint oil (Mentha spicata Linn.) offers behavioral radioprotection: a radiation-induced conditioned taste aversion study.

    PubMed

    Haksar, A; Sharma, A; Chawla, R; Kumar, Raj; Lahiri, S S; Islam, F; Arora, M P; Sharma, R K; Tripathi, R P; Arora, Rajesh

    2009-02-01

    Mentha spicata Linn. (mint), a herb well known for its gastroprotective properties in the traditional system of medicine has been shown to protect against radiation-induced lethality, and recently its constituents have been found to possess calcium channel antagonizing properties. The present study examined the behavioral radioprotective efficacy of mint oil (obtained from Mentha spicata), particularly in mitigating radiation-induced conditioned taste aversion (CTA), which has been proposed as a behavioral endpoint that is mediated by the toxic effects of gamma radiation on peripheral systems, primarily the gastrointestinal system in the Sprague-Dawley rat model. Intraperitoneal administration of Mentha spicata oil 10% (v/v), 1 h before 2 Gy gamma radiation, was found to render significant radioprotection against CTA (p < 0.05), by blocking the saccharin avoidance response within 5 post-treatment observational days, with the highest saccharin intake being observed on day 5. This finding clearly demonstrates that gastroprotective and calcium channel antagonizing properties of Mentha spicata can be effectively utilized in preventing radiation-induced behavioral changes.

  13. Lessons learned using different mouse models during space radiation-induced lung tumorigenesis experiments

    NASA Astrophysics Data System (ADS)

    Wang, Jian; Zhang, Xiangming; Wang, Ping; Wang, Xiang; Farris, Alton B.; Wang, Ya

    2016-06-01

    Unlike terrestrial ionizing radiation, space radiation, especially galactic cosmic rays (GCR), contains high energy charged (HZE) particles with high linear energy transfer (LET). Due to a lack of epidemiologic data for high-LET radiation exposure, it is highly uncertain how high the carcinogenesis risk is for astronauts following exposure to space radiation during space missions. Therefore, using mouse models is necessary to evaluate the risk of space radiation-induced tumorigenesis; however, which mouse model is better for these studies remains uncertain. Since lung tumorigenesis is the leading cause of cancer death among both men and women, and low-LET radiation exposure increases human lung carcinogenesis, evaluating space radiation-induced lung tumorigenesis is critical to enable safe Mars missions. Here, by comparing lung tumorigenesis obtained from different mouse strains, as well as miR-21 in lung tissue/tumors and serum, we believe that wild type mice with a low spontaneous tumorigenesis background are ideal for evaluating the risk of space radiation-induced lung tumorigenesis, and circulating miR-21 from such mice model might be used as a biomarker for predicting the risk.

  14. Mitigation of whole-body gamma radiation-induced damages by Clerodendron infortunatum in mammalian organisms.

    PubMed

    Chacko, Tiju; Menon, Aditya; Majeed, Teeju; Nair, Sivaprabha V; John, Nithu Sara; Nair, Cherupally Krishnan Krishnan

    2016-11-17

    Several phytoceuticals and extracts of medicinal plants are reported to mitigate deleterious effects of ionizing radiation. The potential of hydro-alcoholic extract of Clerodendron infortunatum (CIE) for providing protection to mice exposed to gamma radiation was investigated. Oral administration of CIE bestowed a survival advantage to mice exposed to lethal doses of gamma radiation. Radiation-induced depletion of the total blood count and bone marrow cellularity were prevented by treatment with CIE. Damage to the cellular DNA (as was evident from the comet assay and the micronucleus index) was also found to be decreased upon CIE administration. Radiation-induced damages to intestinal crypt cells was also reduced by CIE. Studies on gene expression in intestinal cells revealed that there was a marked increase in the Bax/Bcl-2 ratio in mice exposed to whole-body 4 Gy gamma radiation, and that administration of CIE resulted in significant lowering of this ratio, suggestive of reduction of radiation-induced apoptosis. Also, in the intestinal tissue of irradiated animals, following CIE treatment, levels of expression of the DNA repair gene Atm were found to be elevated, and there was reduction in the expression of the inflammatory Cox-2 gene. Thus, our results suggest a beneficial use of Clerodendron infortunatum for mitigating radiation toxicity.

  15. Blood glutathione as an index of radiation-induced oxidative stress in mice and humans.

    PubMed

    Navarro, J; Obrador, E; Pellicer, J A; Aseni, M; Viña, J; Estrela, J M

    1997-01-01

    The effect of x-rays on GSH and GSSG levels in blood was studied in mice and humans. An HPLC method that we recently developed was applied to accurately determine GSSG levels in blood. The glutathione redox status (GSH/GSSG) decreases after irradiation. This effect is mainly due to an increase in GSSG levels. Mice received single fraction radiotherapy, at total doses of 1.0 to 7.0 Gy. Changes in GSSG in mouse blood can be detected 10 min after irradiation and last for 6 h within a range of 2.0-7.0 Gy. The highest levels of GSSG (20.1 +/- 2.9 microM), a 4.7-fold increase as compared with controls) in mouse blood are found 2 h after radiation exposure (5 Gy). Breast and lung cancer patients received fractionated radiotherapy at total doses of 50.0 or 60.0 Gy, respectively. GSH/GSSG also decreases in humans in a dose-response fashion. Two reasons may explain the radiation-induced increase in blood GSSG: (a) the reaction of GSH with radiation-induced free radicals resulting in the formation of thyl radicals that react to produce GSSG; and (b) an increase of GSSG release from different organs (e.g., the liver) into the blood. Our results indicate that the glutathione redox ratio in blood can be used as an index of radiation-induced oxidative stress.

  16. Modulation of radiation-induced alteration in the antioxidant status of mice by naringin.

    PubMed

    Jagetia, Ganesh Chandra; Reddy, Tiyyagura Koti

    2005-07-01

    The alteration in the antioxidant status and lipid peroxidation was investigated in Swiss albino mice treated with 2 mg/kg b.wt. naringin, a citrus flavoglycoside, before exposure to 0.5, 1, 2, 3, and 4 Gy gamma radiation. Lipid peroxidation, glutathione, glutathione peroxidase, catalase and superoxide dismutase were determined in the liver and small intestine of mice treated or not with naringin at 0.5, 1, 2, 4 and 8 h post-irradiation. Whole-body irradiation of mice caused a dose-dependent elevation in the lipid peroxidation while a dose-dependent depletion was observed for glutathione, glutathione peroxidase, superoxide dismutase and catalase in both liver as well as small intestine. Treatment of mice with 2 mg/kg b. wt. naringin inhibited the radiation-induced elevation in the lipid peroxidation as well as depletion of glutathione, glutathione peroxidase, superoxide dismutase and catalase in liver and small intestine. Radiation-induced lipid peroxidation increased with time, which was greatest at 2 h post-irradiation and declined thereafter in the liver and small intestine. Similarly, a maximum decline in the glutathione glutathione peroxidase, and superoxide dismutase was observed at 1 h, while catalase showed a maximum decline at 2 h post-irradiation. Our study demonstrates that naringin protects mouse liver and intestine against the radiation-induced damage by elevating the antioxidant status and reducing the lipid peroxidation.

  17. Dynamics of wound healing signaling as a potential therapeutic target for radiation-induced tissue damage.

    PubMed

    Chung, Yih-Lin; Pui, Newman N M

    2015-01-01

    We hypothesized the histone deacetylase inhibitor phenylbutyrate (PB) has beneficial effects on radiation-induced injury by modulating the expression of DNA repair and wound healing genes. Hamsters received a radiosurgical dose of radiation (40 Gy) to the cheek and were treated with varying PB dosing regimens. Gross alteration of the irradiated cheeks, eating function, histological changes, and gene expression during the course of wound healing were compared between treatment groups. Pathological analysis showed decreased radiation-induced mucositis, facilitated epithelial cell growth, and preventing ulcerative wound formation, after short-term PB treatment, but not after vehicle or sustained PB. The radiation-induced wound healing gene expression profile exhibited a sequential transition from the inflammatory and DNA repair phases to the tissue remodeling phase in the vehicle group. Sustained PB treatment resulted in a prolonged wound healing gene expression profile and delayed the wound healing process. Short-term PB shortened the duration of inflammatory cytokine expression, triggered repeated pulsed expression of cell cycle and DNA repair-regulating genes, and promoted earlier oscillatory expression of tissue remodeling genes. Distinct gene expression patterns between sustained and short-term treatment suggest dynamic profiling of wound healing gene expression can be an important part of a biological therapeutic strategy to mitigate radiation-related tissue injury.

  18. Loss of Matrix Metalloproteinase-13 Attenuates Murine Radiation-Induced Pulmonary Fibrosis

    SciTech Connect

    Flechsig, Paul; Hartenstein, Bettina; Teurich, Sybille; Dadrich, Monika; Hauser, Kai; Abdollahi, Amir; Groene, Hermann-Josef; Angel, Peter; Huber, Peter E.

    2010-06-01

    Purpose: Pulmonary fibrosis is a disorder of the lungs with limited treatment options. Matrix metalloproteinases (MMPs) constitute a family of proteases that degrade extracellular matrix with roles in fibrosis. Here we studied the role of MMP13 in a radiation-induced lung fibrosis model using a MMP13 knockout mouse. Methods and Materials: We investigated the role of MMP13 in lung fibrosis by investigating the effects of MMP13 deficiency in C57Bl/6 mice after 20-Gy thoracic irradiation (6-MV Linac). The morphologic results in histology were correlated with qualitative and quantitative results of volume computed tomography (VCT), magnetic resonance imaging (MRI), and clinical outcome. Results: We found that MMP13 deficient mice developed less pulmonary fibrosis than their wildtype counterparts, showed attenuated acute pulmonary inflammation (days after irradiation), and a reduction of inflammation during the later fibrogenic phase (5-6 months after irradiation). The reduced fibrosis in MMP13 deficient mice was evident in histology with reduced thickening of alveolar septi and reduced remodeling of the lung architecture in good correlation with reduced features of lung fibrosis in qualitative and quantitative VCT and MRI studies. The partial resistance of MMP13-deficient mice to fibrosis was associated with a tendency towards a prolonged mouse survival. Conclusions: Our data indicate that MMP13 has a role in the development of radiation-induced pulmonary fibrosis. Further, our findings suggest that MMP13 constitutes a potential drug target to attenuate radiation-induced lung fibrosis.

  19. Inhibition of CDK4/6 protects against radiation-induced intestinal injury in mice

    PubMed Central

    Wei, Liang; Leibowitz, Brian J.; Wang, Xinwei; Epperly, Michael; Greenberger, Joel; Zhang, Lin

    2016-01-01

    Radiotherapy causes dose-limiting toxicity and long-term complications in rapidly renewing tissues, including the gastrointestinal tract. Currently, there is no FDA-approved agent for the prevention or treatment of radiation-induced intestinal injury. In this study, we have shown that PD 0332991 (PD), an FDA-approved selective inhibitor of cyclin-dependent kinase 4/6 (CDK4/6), prevents radiation-induced lethal intestinal injury in mice. Treating mice with PD or a structurally distinct CDK4/6 inhibitor prior to radiation blocked proliferation and crypt apoptosis and improved crypt regeneration. PD treatment also enhanced LGR5+ stem cell survival and regeneration after radiation. PD was an on-target inhibitor of RB phosphorylation and blocked G1/S transition in the intestinal crypts. PD treatment strongly but reversibly inhibited radiation-induced p53 activation, which blocked p53-upregulated modulator of apoptosis–dependent (PUMA-dependent) apoptosis without affecting p21-dependent suppression of DNA damage accumulation, with a repair bias toward nonhomologous end joining. Further, deletion of PUMA synergized with PD treatment for even greater intestinal radioprotection. Our results demonstrate that the cell cycle critically regulates the DNA damage response and survival of intestinal stem cells and support the concept that pharmacological quiescence is a potentially highly effective and selective strategy for intestinal radioprotection. PMID:27701148

  20. Sodium Tanshinone IIA Sulfonate Prevents Radiation-Induced Toxicity in H9c2 Cardiomyocytes

    PubMed Central

    Zhang, Wenjing; Li, Rui; Wang, Yaya; Zhu, Mengwen; Wang, Bowen; Li, Yanling; Li, Dongyun

    2017-01-01

    The present study was designed to elucidate the key parameters associated with X-ray radiation induced oxidative stress and the effects of STS on X-ray-induced toxicity in H9c2 cardiomyocytes. Cytotoxicity of STS and radiation was assessed by MTT. Antioxidant activity was evaluated by SOD and MDA. Apoptosis was measured by the flow cytometry, Hoechst 33258, clonogenic survival assay, and western blot. It was found that the cell viability of H9c2 cells exposed to X-ray radiation was significantly decreased in a dose-dependent manner and was associated with cell cycle arrest at the G0/G1 phase as well as apoptosis. STS treatment significantly reversed the morphological changes, attenuated radiation-induced apoptosis, and improved the antioxidant activity in the H9c2 cells. STS significantly increased the Bcl-2 and Bcl-2/Bax levels and decreased the Bax and caspase-3 levels, compared with the cells treated with radiation alone. STS treatment also resulted in a significant increase in p38-MAPK activation. STS could protect the cells from X-ray-induced cell cycle arrest, oxidative stress, and apoptosis. Therefore, we suggest the STS could be useful for the treatment of radiation-induced cardiovascular injury. PMID:28386289

  1. Standardized Herbal Formula PM014 Inhibits Radiation-Induced Pulmonary Inflammation in Mice

    PubMed Central

    Kim, Jee-Youn; Shin, Dasom; Lee, Gihyun; Kim, Jin-Mo; Kim, Dongwook; An, Yong-Min; Yoo, Byung Rok; Chang, Hanna; Kim, Miran; Cho, Jaeho; Bae, Hyunsu

    2017-01-01

    Radiation therapy is widely used for thoracic cancers. However, it occasionally causes radiation-induced lung injuries, including pneumonitis and fibrosis. Chung-Sang-Bo-Ha-Tang (CSBHT) has been traditionally used to treat chronic pulmonary disease in Korea. PM014, a modified herbal formula derived from CSBHT, contains medicinal herbs of seven species. In our previous studies, PM014 exhibited anti-inflammatory effects in a chronic obstructive pulmonary disease model. In this study, we have evaluated the effects of PM014 on radiation-induced lung inflammation. Mice in the treatment group were orally administered PM014 six times for 2 weeks. Effects of PM014 on radiation pneumonitis were evaluated based on histological findings and differential cell count in bronchoalveolar lavage fluid. PM014 treatment significantly inhibited immune cell recruitment and collagen deposition in lung tissue. Normal lung volume, evaluated by radiological analysis, in PM014-treated mice was higher compared to that in irradiated control mice. PM014-treated mice exhibited significant changes in inspiratory capacity, compliance and tissue damping and elastance. Additionally, PM014 treatment resulted in the downregulation of inflammatory cytokines, chemokines, and fibrosis-related genes and a reduction in the transforming growth factor-β1-positive cell population in lung tissue. Thus, PM014 is a potent therapeutic agent for radiation-induced lung fibrosis and inflammation. PMID:28322297

  2. Basic Fibroblast Growth Factor Ameliorates Endothelial Dysfunction in Radiation-Induced Bladder Injury

    PubMed Central

    Zhang, Shiwei; Qiu, Xuefeng; Zhang, Yanting; Fu, Kai; Zhao, Xiaozhi; Wu, Jinhui; Hu, Yiqiao; Zhu, Weiming; Guo, Hongqian

    2015-01-01

    This study was designed to explore the effect of basic fibroblast growth factor (bFGF) on radiation-induced endothelial dysfunction and histological changes in the urinary bladder. bFGF was administrated to human umbilical vein cells (HUVEC) or urinary bladder immediately after radiation. Reduced expression of thrombomodulin (TM) was indicated in the HUVEC and urinary bladder after treatment with radiation. Decreased apoptosis was observed in HUVEC treated with bFGF. Administration of bFGF increased the expression of TM in HUVEC medium, as well as in the urinary bladder at the early and delayed phases of radiation-induced bladder injury (RIBI). At the early phase, injection of bFGF increased the thickness of urothelium and reduced inflammation within the urinary bladder. At the delayed phase, bFGF was effective in reducing fibrosis within the urinary bladder. Our results indicate that endothelial dysfunction is a prominent feature of RIBI. Administration of bFGF can ameliorate radiation-induced endothelial dysfunction in urinary bladder and preserve bladder histology at early and delayed phases of RIBI. PMID:26351640

  3. Leaf extract of Moringa oleifera prevents ionizing radiation-induced oxidative stress in mice.

    PubMed

    Sinha, Mahuya; Das, Dipesh K; Bhattacharjee, Surajit; Majumdar, Subrata; Dey, Sanjit

    2011-10-01

    The present study evaluated the hepatoprotective effect of aqueous ethanolic Moringa oleifera leaf extract (MoLE) against radiation-induced oxidative stress, which is assessed in terms of inflammation and lipid peroxidation. Swiss albino mice were administered MoLE (300 mg/kg of body weight) for 15 consecutive days before exposing them to a single dose of 5 Gy of ⁶⁰Co γ-irradiation. Mice were sacrificed at 4 hours after irradiation. Liver was collected for immunoblotting and biochemical tests for the detection of markers of hepatic oxidative stress. Nuclear translocation of nuclear factor kappa B (NF-κB) and lipid peroxidation were augmented, whereas the superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and ferric reducing antioxidant power (FRAP) values were decreased by radiation exposure. Translocation of NF-κB from cytoplasm to nucleus and lipid peroxidation were found to be inhibited, whereas increases in SOD, CAT, GSH, and FRAP were observed in the mice treated with MoLE prior to irradiation. Therefore pretreatment with MoLE protected against γ-radiation-induced liver damage. The protection may be attributed to the free radical scavenging activity of MoLE, through which it can ameliorate radiation-induced oxidative stress.

  4. Radiation-induced human endogenous retrovirus (HERV)-R env gene expression by epigenetic control.

    PubMed

    Lee, Ja-Rang; Ahn, Kung; Kim, Yun-Ji; Jung, Yi-Deun; Kim, Heui-Soo

    2012-11-01

    It is commonly accepted that ionizing radiation induces genomic instability by changes in genomic structure, epigenetic regulation and gene expression. Human endogenous retroviruses (HERV)-R also are often differentially expressed between normal and disease tissues under unstable genomic conditions and are implicated in the pathogenesis of several human diseases. To understand the influence of ionizing radiation on HERV-R expression, we performed quantitative reverse transcription-polymerase chain reaction (RT-PCR) analyses using γ-irradiated normal human cells. Compared to nonirradiated cells, HERV-R expression was up-regulated in γ-irradiated cells. The regulatory mechanism of HERV-R expression in irradiated cells was investigated by methylation analyses of HERV-R 5'LTRs and treatment with garcinol. These data indicated that the up-regulated transcription of HERV-R may be regulated by radiation-induced epigenetic changes induced by histone modification, and thus could be of great importance for understanding the relationship between radiation-induced biological effects and transposable elements.

  5. Systematic review of hyperbaric oxygen therapy for the treatment of radiation-induced skin necrosis.

    PubMed

    Borab, Zachary; Mirmanesh, Michael D; Gantz, Madeleine; Cusano, Alessandro; Pu, Lee L Q

    2017-04-01

    Every year, 1.2 million cancer patients receive radiation therapy in the United States. Late radiation tissue injury occurs in an estimated 5-15% of these patients. Tissue injury can include skin necrosis, which can lead to chronic nonhealing wounds. Despite many treatments available to help heal skin necrosis such as hyperbaric oxygen therapy, no clinical guidelines exist and evidence is lacking. The purpose of this review is to identify and comprehensively summarize studies published to date to evaluate the effectiveness of hyperbaric oxygen therapy for the treatment of radiation-induced skin necrosis. Adhering to PRISMA guidelines, a systematic review of currently published articles was performed, evaluating the use of hyperbaric oxygen to treat skin necrosis. Eight articles were identified, including one observational cohort, five case series, and two case reports. The articles describe changes in symptoms and alteration in wound healing of radiation-induced skin necrosis after treatment with hyperbaric oxygen therapy. Hyperbaric oxygen therapy is a safe intervention with promising outcomes; however, additional evidence is needed to endorse its application as a relevant therapy in the treatment of radiation-induced skin necrosis.

  6. Lack of evidence of the effectiveness of primary brachial plexus surgery for infants (under the age of two years) diagnosed with obstetric brachial plexus palsy.

    PubMed

    Bialocerkowski, Andrea; Gelding, Bronwyn

    2006-12-01

    Background  Obstetric brachial plexus palsy, which occurs in 1-3 per 1000 live births, results from traction and/or compression of the brachial plexus in utero, during descent through the birth canal or during delivery. This results in a spectrum of injuries that range in extent of damage and severity and can lead to a lifelong impairment and functional difficulties associated with the use of the affected upper limb. Most infants diagnosed with obstetric brachial plexus palsy receive treatment, such as surgery to the brachial plexus, physiotherapy or occupational therapy, within the first months of life. However, there is controversy regarding the most effective form of management. This review follows on from our previous systematic review which investigated the effectiveness of primary conservative management in infants with obstetric brachial plexus palsy. This systematic review focuses on the effects of primary surgery. Objectives  The objective of this review was to systematically assess and collate all available evidence on effectiveness of primary brachial plexus surgery for infants with obstetric brachial plexus palsy. Search strategy  A systematic literature search was performed using 13 databases: TRIP, MEDLINE, CINAHL, Web of Science, Proquest 5000, Evidence Based Medicine Reviews, Expanded Academic ASAP, Meditext, Science Direct, the Physiotherapy Evidence Database, Proquest Digital Dissertations, Open Archives Initiative Search Engine, the Australian Digital Thesis program. Those studies that were reported in English and published between July 1992 to June 2004 were included in this review. Selection criteria  Quantitative studies that investigated the effectiveness of primary brachial plexus surgery for infants with obstetric brachial plexus palsy were eligible for inclusion into this review. This excluded studies where infants were solely managed conservatively or with pharmacological agents, or underwent surgery for the management of

  7. Epigenetic Analysis of Heavy-ion Radiation Induced Bystander Effects in Mice

    NASA Astrophysics Data System (ADS)

    Zhang, Meng; Sun, Yeqing; Cui, Changna; Xue, Bei

    Abstract: Radiation-induced bystander effect was defined as the induction of damage in neighboring non-hit cells by signals released from directly-irradiated cells. Recently, low dose of high LET radiation induced bystander effects in vivo have been reported more and more. It has been indicated that radiation induced bystander effect was localized not only in bystander tissues but also in distant organs. Genomic, epigenetic and proteomics plays significant roles in regulating heavy-ion radiation stress responses in mice. To identify the molecular mechanism that underlies bystander effects of heavy-ion radiation, the male Balb/c and C57BL mice were exposed head-only to 40, 200, 2000mGy dose of (12) C heavy-ion radiation, while the rest of the animal body was shielded. Directly radiation organ ear and the distant organ liver were detected on 1h, 6h, 12h and 24h after radiation, respectively. Methylation-sensitive amplification polymorphism (MSAP) was used to monitor the level of polymorphic genomic DNA methylation changed with dose and time effects. The results show that heavy-ion irradiated mouse head could induce genomic DNA methylation changes significantly in both the directly radiation organ ear and the distant organ liver. The percent of DNA methylation changes were time-dependent and tissue-specific. Demethylation polymorphism rate was highest separately at 1 h in 200 mGy and 6 h in 2000 mGy after irradiation. The global DNA methylation changes tended to occur in the CG sites. The results illustrated that 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

  8. Combined inhibition of TGFβ and PDGF signaling attenuates radiation-induced pulmonary fibrosis.

    PubMed

    Dadrich, Monika; Nicolay, Nils H; Flechsig, Paul; Bickelhaupt, Sebastian; Hoeltgen, Line; Roeder, Falk; Hauser, Kai; Tietz, Alexandra; Jenne, Jürgen; Lopez, Ramon; Roehrich, Manuel; Wirkner, Ute; Lahn, Michael; Huber, Peter E

    2016-05-01

    Background : Radiotherapy (RT) is a mainstay for the treatment of lung cancer, but the effective dose is often limited by the development of radiation-induced pneumonitis and pulmonary fibrosis. Transforming growth factor β (TGFβ) and platelet-derived growth factor (PDGF) play crucial roles in the development of these diseases, but the effects of dual growth factor inhibition on pulmonary fibrosis development remain unclear. Methods : C57BL/6 mice were treated with 20 Gy to the thorax to induce pulmonary fibrosis. PDGF receptor inhibitors SU9518 and SU14816 (imatinib) and TGFβ receptor inhibitor galunisertib were applied individually or in combinations after RT. Lung density and septal fibrosis were measured by high-resolution CT and MRI. Lung histology and gene expression analyses were performed and Osteopontin levels were studied. Results : Treatment with SU9518, SU14816 or galunisertib individually attenuated radiation-induced pulmonary inflammation and fibrosis and decreased radiological and histological signs of lung damage. Combining PDGF and TGFβ inhibitors showed to be feasible and safe in a mouse model, and dual inhibition significantly attenuated radiation-induced lung damage and extended mouse survival compared to blockage of either pathway alone. Gene expression analysis of irradiated lung tissue showed upregulation of PDGF and TGFβ-dependent signaling components by thoracic irradiation, and upregulation patterns show crosstalk between downstream mediators of the PDGF and TGFβ pathways. Conclusion : Combined small-molecule inhibition of PDGF and TGFβ signaling is a safe and effective treatment for radiation-induced pulmonary inflammation and fibrosis in mice and may offer a novel approach for treatment of fibrotic lung diseases in humans. Translational statement : RT is an effective treatment modality for cancer with limitations due to acute and chronic toxicities, where TGFβ and PDGF play a key role. Here, we show that a combined inhibition of

  9. Combined inhibition of TGFβ and PDGF signaling attenuates radiation-induced pulmonary fibrosis

    PubMed Central

    Dadrich, Monika; Nicolay, Nils H.; Flechsig, Paul; Bickelhaupt, Sebastian; Hoeltgen, Line; Roeder, Falk; Hauser, Kai; Tietz, Alexandra; Jenne, Jürgen; Lopez, Ramon; Roehrich, Manuel; Wirkner, Ute; Lahn, Michael; Huber, Peter E.

    2016-01-01

    ABSTRACT Background: Radiotherapy (RT) is a mainstay for the treatment of lung cancer, but the effective dose is often limited by the development of radiation-induced pneumonitis and pulmonary fibrosis. Transforming growth factor β (TGFβ) and platelet-derived growth factor (PDGF) play crucial roles in the development of these diseases, but the effects of dual growth factor inhibition on pulmonary fibrosis development remain unclear. Methods: C57BL/6 mice were treated with 20 Gy to the thorax to induce pulmonary fibrosis. PDGF receptor inhibitors SU9518 and SU14816 (imatinib) and TGFβ receptor inhibitor galunisertib were applied individually or in combinations after RT. Lung density and septal fibrosis were measured by high-resolution CT and MRI. Lung histology and gene expression analyses were performed and Osteopontin levels were studied. Results: Treatment with SU9518, SU14816 or galunisertib individually attenuated radiation-induced pulmonary inflammation and fibrosis and decreased radiological and histological signs of lung damage. Combining PDGF and TGFβ inhibitors showed to be feasible and safe in a mouse model, and dual inhibition significantly attenuated radiation-induced lung damage and extended mouse survival compared to blockage of either pathway alone. Gene expression analysis of irradiated lung tissue showed upregulation of PDGF and TGFβ-dependent signaling components by thoracic irradiation, and upregulation patterns show crosstalk between downstream mediators of the PDGF and TGFβ pathways. Conclusion: Combined small-molecule inhibition of PDGF and TGFβ signaling is a safe and effective treatment for radiation-induced pulmonary inflammation and fibrosis in mice and may offer a novel approach for treatment of fibrotic lung diseases in humans. Translational statement: RT is an effective treatment modality for cancer with limitations due to acute and chronic toxicities, where TGFβ and PDGF play a key role. Here, we show that a combined

  10. Upper Limb Multifactorial Movement Analysis in Brachial Plexus Birth Injury

    PubMed Central

    Bahm, Jorg

    2016-01-01

    Multifactorial motion analysis was first established for gait and then developed in the upper extremity. Recordings of infrared light reflecting sensitive passive markers in space, combined with surface eletromyographic recordings and/or transmitted forces, allow eclectic study of muscular coordination in the upper limb. Brachial plexus birth injury is responsible for various patterns of muscle weakness, imbalance, and/or simultaneous activation, soft tissue contractures, and bone-joint deformities, leading to individual motion patterns and adaptations, which we studied by means of motion analysis tools. We describe the technical development and examination setup to evaluate motion impairment and present first clinical results. Motion analysis is a reliable objective assessment tool allowing precise pre- and postoperative multimodal evaluation of upper limb function. Level of evidence: II. PMID:28077954

  11. Brachial plexus injury: the London experience with supraclavicular traction lesions.

    PubMed

    Birch, Rolfe

    2009-01-01

    In this article, the author details the experiences of his hospital and other London hospitals in treating brachial plexus injury. As noted, important advances have been made in methods of diagnosis and repair. Myelography was replaced by CT scan and later by MRI. Among the topics the author explores are diagnosis (including pain, the presence or absence of the Tinel sign, and the irradiation of pins and needles) and the principles of repair. The author emphasizes that it is imperative that ruptured nerves be repaired as soon as possible, with the closed traction lesion coming, in urgency, close behind reattachment of the amputated hand or repair of a great artery and a trunk nerve in the combined lesion. Finally, the article concludes that the surgeon must be actively engaged in the whole process of rehabilitation and treatment of pain. This is part of a Point-Counterpoint discussion with Dr. David G. Kline's presentation of "A Personal Experience."

  12. Surgical treatment of brachial plexus injuries in adults.

    PubMed

    Ricardo, Monreal

    2005-12-01

    We carried out a retrospective review of 32 consecutive patients (30 adults and two children) with total or partial lesions of the brachial plexus who had surgical repair using nerve grafting, neurotisation, and neurolysis between January 1991 and December 2003. The outcome measures of muscular strength were correlated with the type of lesion, age, preoperative time, length and number of grafts, and time to reinnervation of the biceps. The function of the upper limb was also evaluated. There was a significant correlation between muscular strength after surgical repair and both the preoperative time and the length of the nerve graft. There was also a significant correlation between muscular strength and the number of grafts. Muscular strength was better when the neurolysis was done before six months. When neurosurgical repair and reconstructive procedures were performed, the function of the upper limb was improved.

  13. Obstetrical brachial plexus injury (OBPI): Canada's national clinical practice guideline

    PubMed Central

    Coroneos, Christopher J; Voineskos, Sophocles H; Christakis, Marie K; Thoma, Achilleas; Bain, James R; Brouwers, Melissa C

    2017-01-01

    Objective The objective of this study was to establish an evidence-based clinical practice guideline for the primary management of obstetrical brachial plexus injury (OBPI). This clinical practice guideline addresses 4 existing gaps: (1) historic poor use of evidence, (2) timing of referral to multidisciplinary care, (3) Indications and timing of operative nerve repair and (4) distribution of expertise. Setting The guideline is intended for all healthcare providers treating infants and children, and all specialists treating upper extremity injuries. Participants The evidence interpretation and recommendation consensus team (Canadian OBPI Working Group) was composed of clinicians representing each of Canada's 10 multidisciplinary centres. Outcome measures An electronic modified Delphi approach was used for consensus, with agreement criteria defined a priori. Quality indicators for referral to a multidisciplinary centre were established by consensus. An original meta-analysis of primary nerve repair and review of Canadian epidemiology and burden were previously completed. Results 7 recommendations address clinical gaps and guide identification, referral, treatment and outcome assessment: (1) physically examine for OBPI in newborns with arm asymmetry or risk factors; (2) refer newborns with OBPI to a multidisciplinary centre by 1 month; (3) provide pregnancy/birth history and physical examination findings at birth; (4) multidisciplinary centres should include a therapist and peripheral nerve surgeon experienced with OBPI; (5) physical therapy should be advised by a multidisciplinary team; (6) microsurgical nerve repair is indicated in root avulsion and other OBPI meeting centre operative criteria; (7) the common data set includes the Narakas classification, limb length, Active Movement Scale (AMS) and Brachial Plexus Outcome Measure (BPOM) 2 years after birth/surgery. Conclusions The process established a new network of opinion leaders and researchers for further

  14. OCT/PS-OCT imaging of brachial plexus neurovascular structures

    NASA Astrophysics Data System (ADS)

    Raphael, David T.; Zhang, Jun; Zhang, Yaoping; Chen, Zhongping; Miller, Carol; Zhou, Li

    2004-07-01

    Introduction: Optical coherence tomography (OCT) allows high-resolution imaging (less than 10 microns) of tissue structures. A pilot study with OCT and polarization-sensitive OCT (PS-OCT) was undertaken to image ex-vivo neurovascular structures (vessels, nerves) of the canine brachial plexus. Methods: OCT is an interferometry-based optical analog of B-mode ultrasound, which can image through non-transparent biological tissues. With approval of the USC Animal Care and Use Committee, segments of the supra- and infraclavicular brachial plexus were excised from euthanized adult dogs, and the ex-vivo specimens were placed in cold pH-buffered physiologic solution. An OCT beam, in micrometer translational steps, scanned the fixed-position bisected specimens in transverse and longitudinal views. Two-dimensional images were obtained from identified arteries and nerves, with specific sections of interest stained with hematoxylin-eosin for later imaging through a surgical microscope. Results: with the beam scan direction transverse to arteries, the resulting OCT images showed an identifiable arterial lumen and arterial wall tissue layers. By comparison, transverse beam OCT images of nerves revealed a multitude of smaller nerve bundles contained within larger circular-shaped fascicles. PS-OCT imaging was helpful in showing the characteristic birefringence exhibited by arrayed neural structures. Discussion: High-resolution OCT imaging may be useful in the optical identification of neurovascular structures during attempted regional nerve blockade. If incorporated into a needle-shaped catheter endoscope, such a technology could prevent intraneural and intravascular injections immediately prior to local anesthetic injection. The major limitation of OCT is that it can form a coherent image of tissue structures only to a depth of 1.5 - 2 mm.

  15. Morphometric Atlas Selection for Automatic Brachial Plexus Segmentation

    SciTech Connect

    Van de Velde, Joris; Wouters, Johan; Vercauteren, Tom; De Gersem, Werner; Duprez, Fréderic; De Neve, Wilfried; Van Hoof, Tom

    2015-07-01

    Purpose: The purpose of this study was to determine the effects of atlas selection based on different morphometric parameters, on the accuracy of automatic brachial plexus (BP) segmentation for radiation therapy planning. The segmentation accuracy was measured by comparing all of the generated automatic segmentations with anatomically validated gold standard atlases developed using cadavers. Methods and Materials: Twelve cadaver computed tomography (CT) atlases (3 males, 9 females; mean age: 73 years) were included in the study. One atlas was selected to serve as a patient, and the other 11 atlases were registered separately onto this “patient” using deformable image registration. This procedure was repeated for every atlas as a patient. Next, the Dice and Jaccard similarity indices and inclusion index were calculated for every registered BP with the original gold standard BP. In parallel, differences in several morphometric parameters that may influence the BP segmentation accuracy were measured for the different atlases. Specific brachial plexus-related CT-visible bony points were used to define the morphometric parameters. Subsequently, correlations between the similarity indices and morphometric parameters were calculated. Results: A clear negative correlation between difference in protraction-retraction distance and the similarity indices was observed (mean Pearson correlation coefficient = −0.546). All of the other investigated Pearson correlation coefficients were weak. Conclusions: Differences in the shoulder protraction-retraction position between the atlas and the patient during planning CT influence the BP autosegmentation accuracy. A greater difference in the protraction-retraction distance between the atlas and the patient reduces the accuracy of the BP automatic segmentation result.

  16. Protection against radiation-induced oxidative stress in cultured human epithelial cells by treatment with antioxidant agents

    SciTech Connect

    Wan, X. Steven; Ware, Jeffrey H.; Zhou, Zhaozong; Donahue, Jeremiah J.; Guan, Jun; Kennedy, Ann R. . E-mail: akennedy@mail.med.upenn.edu

    2006-04-01

    Purpose: To evaluate the protective effects of antioxidant agents against space radiation-induced oxidative stress in cultured human epithelial cells. Methods and Materials: The effects of selected concentrations of N-acetylcysteine, ascorbic acid, sodium ascorbate, co-enzyme Q10, {alpha}-lipoic acid, L-selenomethionine, and vitamin E succinate on radiation-induced oxidative stress were evaluated in MCF10 human breast epithelial cells exposed to radiation with X-rays, {gamma}-rays, protons, or high mass, high atomic number, and high energy particles using a dichlorofluorescein assay. Results: The results demonstrated that these antioxidants are effective in protecting against radiation-induced oxidative stress and complete or nearly complete protection was achieved by treating the cells with a combination of these agents before and during the radiation exposure. Conclusion: The combination of antioxidants evaluated in this study is likely be a promising countermeasure for protection against space radiation-induced adverse biologic effects.

  17. Crosstalk between telomere maintenance and radiation effects: A key player in the process of radiation-induced carcinogenesis

    PubMed Central

    Shim, Grace; Ricoul, Michelle; Hempel, William M.; Azzam, Edouard I.; Sabatier, Laure

    2014-01-01

    It is well established that ionizing radiation induces chromosomal damage, both following direct radiation exposure and via non-targeted (bystander) effects, activating DNA damage repair pathways, of which the proteins are closely linked to telomeric proteins and telomere maintenance. Long-term propagation of this radiation-induced chromosomal damage during cell proliferation results in chromosomal instability. Many studies have shown the link between radiation exposure and radiation-induced changes in oxidative stress and DNA damage repair in both targeted and non-targeted cells. However, the effect of these factors on telomeres, long established as guardians of the genome, still remains to be clarified. In this review, we will focus on what is known about how telomeres are affected by exposure to low- and high-LET ionizing radiation and during proliferation, and will discuss how telomeres may be a key player in the process of radiation-induced carcinogenesis. PMID:24486376

  18. Restoration and protection of brachial plexus injury: hot topics in the last decade.

    PubMed

    Zhang, Kaizhi; Lv, Zheng; Liu, Jun; Zhu, He; Li, Rui

    2014-09-15

    Brachial plexus injury is frequently induced by injuries, accidents or birth trauma. Upper limb function may be partially or totally lost after injury, or left permanently disabled. With the development of various medical technologies, different types of interventions are used, but their effectiveness is wide ranging. Many repair methods have phasic characteristics, i.e., repairs are done in different phases. This study explored research progress and hot topic methods for protection after brachial plexus injury, by analyzing 1,797 articles concerning the repair of brachial plexus injuries, published between 2004 and 2013 and indexed by the Science Citation Index database. Results revealed that there are many methods used to repair brachial plexus injury, and their effects are varied. Intervention methods include nerve transfer surgery, electrical stimulation, cell transplantation, neurotrophic factor therapy and drug treatment. Therapeutic methods in this field change according to the hot topic of research.

  19. Screening for Peripheral Artery Disease and Cardiovascular Disease Risk Assessment with Ankle Brachial Index in Adults

    MedlinePlus

    Understanding Task Force Recommendations Screening for Peripheral Artery Disease and Cardiovascular Disease Risk Assessment with Ankle Brachial Index in Adults The U.S. Preventive Services Task Force (Task Force) has issued a ...

  20. Restoration and protection of brachial plexus injury: hot topics in the last decade

    PubMed Central

    Zhang, Kaizhi; Lv, Zheng; Liu, Jun; Zhu, He; Li, Rui

    2014-01-01

    Brachial plexus injury is frequently induced by injuries, accidents or birth trauma. Upper limb function may be partially or totally lost after injury, or left permanently disabled. With the development of various medical technologies, different types of interventions are used, but their effectiveness is wide ranging. Many repair methods have phasic characteristics, i.e., repairs are done in different phases. This study explored research progress and hot topic methods for protection after brachial plexus injury, by analyzing 1,797 articles concerning the repair of brachial plexus injuries, published between 2004 and 2013 and indexed by the Science Citation Index database. Results revealed that there are many methods used to repair brachial plexus injury, and their effects are varied. Intervention methods include nerve transfer surgery, electrical stimulation, cell transplantation, neurotrophic factor therapy and drug treatment. Therapeutic methods in this field change according to the hot topic of research. PMID:25374596

  1. Reliability of 3D upper limb motion analysis in children with obstetric brachial plexus palsy.

    PubMed

    Mahon, Judy; Malone, Ailish; Kiernan, Damien; Meldrum, Dara

    2017-03-01

    Kinematics, measured by 3D upper limb motion analysis (3D-ULMA), can potentially increase understanding of movement patterns by quantifying individual joint contributions. Reliability in children with obstetric brachial plexus palsy (OBPP) has not been established.

  2. Contralateral Spinal Accessory Nerve Transfer: A New Technique in Panavulsive Brachial Plexus Palsy.

    PubMed

    Zermeño-Rivera, Jaime; Gutiérrez-Amavizca, Bianca Ethel

    2015-06-01

    Brachial plexus avulsion results from excessive stretching and can occur secondary to motor vehicle accidents, mainly in motorcyclists. In a 28-year-old man with panavulsive brachial plexus palsy, we describe an alternative technique to repair brachial plexus avulsion and to stabilize and preserve shoulder function by transferring the contralateral spinal accessory nerve to the suprascapular nerve. We observed positive clinical and electromyographic results in sternocleidomastoid, trapezius, supraspinatus, infraspinatus, pectoralis, triceps, and biceps, with good outcome and prognosis for shoulder function at 12 months after surgery. This technique provides a unique opportunity for patients suffering from severe brachial plexus injuries and lacking enough donor nerves to obtain shoulder stability and mobility while avoiding bone fusion and preserving functionality of the contralateral shoulder with favorable postoperative outcomes.

  3. Neuroanatomy of the brachial plexus: normal and variant anatomy of its formation.

    PubMed

    Johnson, Elizabeth O; Vekris, Marios; Demesticha, Theano; Soucacos, Panayotis N

    2010-03-01

    The brachial plexus is the complex network of nerves, extending from the neck to the axilla, which supplies motor, sensory, and sympathetic fibers to the upper extremity. Typically, it is formed by the union of the ventral primary rami of the spinal nerves, C5-C8 & T1, the so-called "roots" of the brachial plexus. By examining the neural architecture of the brachial plexus, the most constant arrangement of nerve fibers can be delineated, and the most predominate variations in the neural architecture defined. A thorough understanding of the neuroanatomy of the brachial plexus, with an appreciation of the possible anatomic variations that may occur is necessary for effective clinical practice.

  4. Brachial Plexus Injury from CT-Guided RF Ablation Under General Anesthesia

    SciTech Connect

    Shankar, Sridhar Sonnenberg, Eric van; Silverman, Stuart G.; Tuncali, Kemal; Flanagan, Hugh L.; Whang, Edward E.

    2005-06-15

    Brachial plexus injury in a patient under general anesthesia (GA) is not uncommon, despite careful positioning and, particularly, awareness of the possibility. The mechanism of injury is stretching and compression of the brachial plexus over a prolonged period. Positioning the patient within the computed tomography (CT) gantry for abdominal or chest procedures can simulate a surgical procedure, particularly when GA is used. The potential for brachial plexus injury is increased if the case is prolonged and the patient's arms are raised above the head to avoid CT image degradation from streak artifacts. We report a case of profound brachial plexus palsy following a CT-guided radiofrequency ablation procedure under GA. Fortunately, the patient recovered completely. We emphasize the mechanism of injury and detail measures to combat this problem, such that radiologists are aware of this potentially serious complication.

  5. Investigation of brachial plexus traction lesions by peripheral and spinal somatosensory evoked potentials.

    PubMed Central

    Jones, S J

    1979-01-01

    Peripheral, spinal and cortical somatosensory evoked potentials were recorded in 26 patients with unilateral traction injuries of the brachial plexus ganglia. Of 10 cases explored surgically the recordings correctly anticipated the major site of the lesion in eight. PMID:422958

  6. High-frequency detection of the formation and stabilization of a radiation-induced defect cluster in semiconductor structures

    SciTech Connect

    Puzanov, A. S.; Obolenskiy, S. V. Kozlov, V. A.; Volkova, E. V.; Paveliev, D. G.

    2015-12-15

    The processes of the formation and stabilization of a radiation-induced defect cluster upon the arrival of a fast neutron to the space-charge region of a semiconductor diode are analyzed. The current pulse formed by secondary electrons is calculated and the spectrum of the signal generated by the diode (detector) under the action of an instantaneous neutron flux of the fission spectrum is determined. The possibility of experimental detection of the picosecond radiation-induced transition processes is discussed.

  7. Implication of Prostaglandins and Histamine H1 and H2 Receptors in Radiation-Induced Temperature Responses of Rats

    DTIC Science & Technology

    1988-05-01

    1988) S Implication of Prostaglandins and Histamine H1 and H 2 Receptors in Radiation-Induced Temperature Responses of Rats SATHASIVA B. KANDASAMY ... KANDASAMY , S. B., HUNT. W. A., AND MICKLEY, G. A. Implications of Prostaglandins and Histamine H I and H2 Receptors in Radiation-Induced Temperature...lateral ventricle according to coordinates derived from the atlas of Pelligrino et al. (31): 0.8 mm posterior to bregma. 2.5 mm lateral. 44 KANDASAMY , HUNT

  8. Vascular patterns of upper limb: an anatomical study with accent on superficial brachial artery

    PubMed Central

    Kachlik, David; Konarik, Marek; Baca, Vaclav

    2011-01-01

    The aim of the study was to evaluate the terminal segmentation of the axillary artery and to present four cases of anomalous branching of the axillary artery, the superficial brachial artery (arteria brachialis superficialis), which is defined as the brachial artery that runs superficially to the median nerve. Totally, 130 cadaveric upper arms embalmed by classical formaldehyde technique from collections of the Department of Anatomy, Third Faculty of Medicine, Charles University in Prague, were macroscopically dissected with special focus on the branching arrangement of the axillary artery. The most distal part of the axillary artery (infrapectoral part) terminated in four cases as a bifurcation into two terminal branches: the superficial brachial artery and profunda brachii artery, denominated according to their relation to the median nerve. The profunda brachii artery primarily gave rise to the main branches of the infrapectoral part of the axillary artery. The superficial brachial artery descended to the cubital fossa where it assumed the usual course of the brachial artery in two cases and in the other two cases its branches (the radial and ulnar arteries) passed superficially to the flexors. The incidence of the superficial brachial artery in our study was 5% of cases. The reported incidence is a bit contradictory, from 0.12% to 25% of cases. The anatomical knowledge of the axillary region is of crucial importance for neurosurgeons and specialists using the radiodiagnostic techniques, particularly in cases involving traumatic injuries. The improved knowledge would allow more accurate diagnostic interpretations and surgical treatment. PMID:21342134

  9. Effects of Berberine Against Radiation-Induced Intestinal Injury in Mice

    SciTech Connect

    Li Guanghui; Zhang Yaping; Tang Jinliang; Chen Zhengtang; Hu Yide; Wei Hong; Li Dezhi; Hao Ping; Wang Donglin

    2010-08-01

    Purpose: Radiation-induced intestinal injury is a significant clinical problem in patients undergoing abdominal radiotherapy (RT). Berberine has been used as an antimicrobial, anti-inflammatory, and antimotility agent. The present study investigated the protective effect of berberine against radiation-induced intestinal injury. Methods and Materials: The mice were administrated berberine or distilled water. A total of 144 mice underwent 0, 3, 6, 12, or 16 Gy single session whole-abdominal RT and 16 mice underwent 3 Gy/fraction/d for four fractions of fractionated abdominal RT. Tumor necrosis factor-{alpha}, interleukin-10, diamine oxidase, intestinal fatty acid-binding protein, malonaldehyde, and apoptosis were assayed in the mice after RT. The body weight and food intake of the mice receiving fractionated RT were recorded. Another 72 mice who had undergone 12, 16, or 20 Gy abdominal RT were monitored for mortality every 12 h. Results: The body weight and food intake of the mice administered with distilled water decreased significantly compared with before RT. After the same dose of abdominal RT, tumor necrosis factor-{alpha}, diamine oxidase, intestinal fatty acid-binding protein in plasma and malonalhehyde and apoptosis of the intestine were significantly greater in the control group than in the mice administered berberine (p < .05-.01). In contrast, interleukin-10 in the mice with berberine treatment was significantly greater than in the control group (p < .01). A similar result was found in the fractionated RT experiment and at different points after 16 Gy abdominal RT (p < .05-.01). Berberine treatment significantly delayed the point of death after 20 Gy, but not 16 Gy, abdominal RT (p < .01). Conclusion: Treatment with berberine can delay mortality and attenuated intestinal injury in mice undergoing whole abdominal RT. These findings could provide a useful therapeutic strategy for radiation-induced intestinal injury.

  10. Smad, but not MAPK, pathway mediates the expression of type I collagen in radiation induced fibrosis

    SciTech Connect

    Yano, Hiroyuki; Hamanaka, Ryoji; Nakamura, Miki; Sumiyoshi, Hideaki; Matsuo, Noritaka; Yoshioka, Hidekatsu

    2012-02-17

    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. Real 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.

  11. Carboplatin enhances the production and persistence of radiation-induced DNA single-strand breaks

    SciTech Connect

    Yang, L.; Douple, E.B.; O`Hara, J.A.; Wang, H.J.

    1995-09-01

    Fluorometric analysis of DNA unwinding and alkaline elution were used to investigate the production and persistence of DNA single-strand breaks (SSBs) in Chinese hamster V79 and xrs-5 cells treated with the chemotherapeutic agent carboplatin in combination with radiation. Carboplatin was administered to cells before irradiation in hypoxic conditions, or the drug was added immediately after irradiation during the postirradiation recovery period in air. The results of DNA unwinding studies suggest that carboplatin enhances the production of radiation-induced SSBs in hypoxic V79 cells and xrs-5 cells by a factor of 1.86 and 1.83, respectively, when combined with radiation compared to the SSBs produced by irradiation alone. Carboplatin alone did not produce a measureable number of SSBs. Alkaline elution profiles also indicated that the rate of elution of SSBs was higher in cells treated with the carboplatin is present after irradiation and during the postirradiation recovery period, the rejoining of radiation-induced SSBs by a factor of 1.46 in V79 cells with 20 Gy irradiation and by a factor of 2.02 in xrs-5 cells with 20 Gy irradiation. When carboplatin is present after irradiation and during the postirradiation recovery period, the rejoining of radiation-induced SSBs is inhibited during this postirradiation incubation period (radiopotentiation) with a relative inhibition factor at 1 h postirradiation of 1.25 in V79 cells and 1.15 in xrs-5 cells. An increased production and persistence of SSBs resulting from the interaction of carboplatin with radiation may be an important step in the mechanism responsible for the potentiated cell killing previously from studies in animal tumors and in cultured cells. 31 refs., 7 figs.

  12. Gossypetin ameliorates ionizing radiation-induced oxidative stress in mice liver--a molecular approach.

    PubMed

    Khan, Amitava; Manna, Krishnendu; Das, Dipesh Kr; Kesh, Swaraj Bandhu; Sinha, Mahuya; Das, Ujjal; Biswas, Sushobhan; Sengupta, Aaveri; Sikder, Kunal; Datta, Sanjukta; Ghosh, Mahua; Chakrabarty, Anindita; Banerji, Asoke; Dey, Sanjit

    2015-10-01

    Radioprotective action of gossypetin (GTIN) against gamma (γ)-radiation-induced oxidative stress in liver was explored in the present article. Our main aim was to evaluate the protective efficacy of GTIN against radiation-induced alteration of liver in murine system. To evaluate the effect of GTIN, it was orally administered to mice at a dose of 30 mg/kg body weight for three consecutive days prior to γ-radiation at a dose of 5 Gy. Radioprotective efficacy of GTIN were evaluated at physiological, cellular, and molecular level using biochemical analysis, comet assay, flow cytometry, histopathology, immunofluorescence, and immunoblotting techniques. Ionizing radiation was responsible for augmentation of hepatic oxidative stress in terms of lipid peroxidation and depletion of endogenous antioxidant enzymes. Immunoblotting and immunofluorescence studies showed that irradiation enhanced the nuclear translocation of nuclear factor kappa B (NF-κB) level, which leads to hepatic inflammation. To investigate further, we found that radiation induced the activation of stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK)-mediated apoptotic pathway and deactivation of the NF-E2-related factor 2 (Nrf2)-mediated redox signaling pathway, whereas GTIN pretreatment ameliorated these radiation-mediated effects. This is the novel report where GTIN rationally validated the molecular mechanism in terms of the modulation of cellular signaling system' instead of ' This is the novel report where GTIN is rationally validated in molecular terms to establish it as promising radioprotective agents. This might be fruitful especially for nuclear workers and defense personnel assuming the possibility of radiation exposure.

  13. Administration of interleukin-6 stimulates multilineage hematopoiesis and accelerates recovery from radiation-induced hematopoietic depression

    SciTech Connect

    Patchen, M.L.; MacVittie, T.J.; Williams, J.L.; Schwartz, G.N.; Souza, L.M. )

    1991-02-01

    Hematopoietic depression and subsequent susceptibility to potentially lethal opportunistic infections are well-documented phenomena following radiotherapy. Methods to therapeutically mitigate radiation-induced myelosuppression could offer great clinical value. In vivo studies have demonstrated that interleukin-6 (IL-6) stimulates pluripotent hematopoietic stem cell (CFU-s), granulocyte-macrophage progenitor cell (GM-CFC), and erythroid progenitor cell (CFU-e) proliferation in normal mice. Based on these results, the ability of IL-6 to stimulate hematopoietic regeneration following radiation-induced hematopoietic injury was also evaluated. C3H/HeN female mice were exposed to 6.5 Gy 60Co radiation and subcutaneously administered either saline or IL-6 on days 1 through 3 or 1 through 6 postexposure. On days 7, 10, 14, 17, and 22, femoral and splenic CFU-s, GM-CFC, and CFU-e contents and peripheral blood white cell, red cell, and platelet counts were determined. Compared with saline treatment, both 3-day and 6-day IL-6 treatments accelerated hematopoietic recovery; 6-day treatment produced the greater effects. For example, compared with normal control values (N), femoral and splenic CFU-s numbers in IL-6-treated mice 17 days postirradiation were 27% N and 136% N versus 2% N and 10% N in saline-treated mice. At the same time, bone marrow and splenic GM-CFC values were 58% N and 473% N versus 6% N and 196% N in saline-treated mice; bone marrow and splenic CFU-e numbers were 91% N and 250% N versus 31% N and 130% N in saline-treated mice; and peripheral blood white cell, red cell, and platelet values were 210% N, 60% N, and 24% N versus 18% N, 39% N, and 7% N in saline-treated mice. These studies demonstrate that therapeutically administered IL-6 can effectively accelerate multilineage hematopoietic recovery following radiation-induced hematopoietic injury.

  14. Quercetin liposomes protect against radiation-induced pulmonary injury in a murine model.

    PubMed

    Liu, Hao; Xue, Jian-Xing; Li, Xing; Ao, Rui; Lu, You

    2013-08-01

    In the present study, the hypothesis that quercetin liposomes are able to effectively protect against radiation-induced pulmonary injury in a murine model was tested. C57BL/6J mice receiving whole-thorax radiotherapy (16 Gy) were randomly divided into three groups: control, radiation therapy plus saline (RT+NS) and RT plus quercetin (RT+QU). At 1, 4, 8 and 24 weeks post-irradiation, lung injury was assessed by measuring oxidative damage and the extent of acute pneumonitis and late fibrosis. In the lung tissues from the RT+NS group, the malondialdehyde (MDA) levels were significantly elevated and superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activities were significantly reduced; the total cell counts and inflammatory cell proportions in the bronchoalveolar lavage fluid (BALF), plasma tumor necrosis factor (TNF)-α and transforming growth factor (TGF)-β1 concentrations and the hydroxyproline (HP) content were significantly increased. Quercetin liposome administration significantly reduced the MDA content and increased SOD and GSH-PX activities in the lung tissues, and reduced the total cell counts and inflammatory cell proportions in the BALF, plasma TNF-α and TGF-β1 concentrations and the HP content in the lung tissues. A histological examination revealed suppression of the inflammatory response and reduced TGF-β1 expression and fibrosis scores. Radiation-induced oxidative damage ranged from pneumonitis to lung fibrosis. Quercetin liposomes were shown to protect against radiation-induced acute pneumonitis and late fibrosis, potentially by reducing oxidative damage.

  15. Accelerated senescence in skin in a murine model of radiation-induced multi-organ injury.

    PubMed

    McCart, Elizabeth A; Thangapazham, Rajesh L; Lombardini, Eric D; Mog, Steven R; Panganiban, Ronald Allan M; Dickson, Kelley M; Mansur, Rihab A; Nagy, Vitaly; Kim, Sung-Yop; Selwyn, Reed; Landauer, Michael R; Darling, Thomas N; Day, Regina M

    2017-03-18

    Accidental high-dose radiation exposures can lead to multi-organ injuries, including radiation dermatitis. The types of cellular damage leading to radiation dermatitis are not completely understood. To identify the cellular mechanisms that underlie radiation-induced skin injury in vivo, we evaluated the time-course of cellular effects of radiation (14, 16 or 17 Gy X-rays; 0.5 Gy/min) in the skin of C57BL/6 mice. Irradiation of 14 Gy induced mild inflammation, observed histologically, but no visible hair loss or erythema. However, 16 or 17 Gy radiation induced dry desquamation, erythema and mild ulceration, detectable within 14 days post-irradiation. Histological evaluation revealed inflammation with mast cell infiltration within 14 days. Fibrosis occurred 80 days following 17 Gy irradiation, with collagen deposition, admixed with neutrophilic dermatitis, and necrotic debris. We found that in cultures of normal human keratinocytes, exposure to 17.9 Gy irradiation caused the upregulation of p21/waf1, a marker of senescence. Using western blot analysis of 17.9 Gy-irradiated mice skin samples, we also detected a marker of accelerated senescence (p21/waf1) 7 days post-irradiation, and a marker of cellular apoptosis (activated caspase-3) at 30 days, both preceding histological evidence of inflammatory infiltrates. Immunohistochemistry revealed reduced epithelial stem cells from hair follicles 14-30 days post-irradiation. Furthermore, p21/waf1 expression was increased in the region of the hair follicle stem cells at 14 days post 17 Gy irradiation. These data indicate that radiation induces accelerated cellular senescence in the region of the stem cell population of the skin.

  16. Radiation induced bystander effect by GAP junction channels in human fibroblast cell

    NASA Astrophysics Data System (ADS)

    Furusawa, Y.; Shao, C.; Aoki, M.; Kobayashi, Y.; Funayama, T.; Ando, K.

    The chemical factor involved in bystander effect and its transfer pathway were investigated in a confluent human fibroblast cell (AG1522) population. Micronuclei (MN) and G1-phase arrest were detected in cells irradiated by carbon (~100 keV/μm) ions at HIMAC. A very low dose irradiation showed a high effectiveness in producing MN, suggesting a bystander effect. This effectiveness was enhanced by 8-Br-cAMP treatment that increases gap junctional intercellular communication (GJIC). On the other hand, the effect was reduced by 5% DMSO treatment, which reduce the reactive oxygen species (ROS), and suppressed by 100 μM lindane treatment, an inhibitor of GJIC. In addition, the radiation-induced G1-phase arrest was also enhanced by cAMP, and reduced or suppressed by DMSO or lindane. A microbeam device (JAERI) was also used for these studies. It was found that exposing one single cell in a confluent cell population to exactly one argon (~1260 keV/μm) or neon (~430 keV/ μm) ion, additional MN could be detected in many other unirradiated cells. The yield of MN increased with the number of irradiated cells. However, there was no significant difference in the MN induction when the cells were irradiated by increasing number of particles. MN induction by bystander effect was partly reduced by DMSO, and effectively suppressed by lindane. Our results obtained from both random irradiation and precise numbered irradiation indicate that both GJIC and ROS contributed to the radiation-induced bystander effect, but the cell gap junction channels likely play an essential role in the release and transfer of radiation-induced chemical factors.

  17. Quercetin liposomes protect against radiation-induced pulmonary injury in a murine model

    PubMed Central

    LIU, HAO; XUE, JIAN-XING; LI, XING; AO, RUI; LU, YOU

    2013-01-01

    In the present study, the hypothesis that quercetin liposomes are able to effectively protect against radiation-induced pulmonary injury in a murine model was tested. C57BL/6J mice receiving whole-thorax radiotherapy (16 Gy) were randomly divided into three groups: control, radiation therapy plus saline (RT+NS) and RT plus quercetin (RT+QU). At 1, 4, 8 and 24 weeks post-irradiation, lung injury was assessed by measuring oxidative damage and the extent of acute pneumonitis and late fibrosis. In the lung tissues from the RT+NS group, the malondialdehyde (MDA) levels were significantly elevated and superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activities were significantly reduced; the total cell counts and inflammatory cell proportions in the bronchoalveolar lavage fluid (BALF), plasma tumor necrosis factor (TNF)-α and transforming growth factor (TGF)-β1 concentrations and the hydroxyproline (HP) content were significantly increased. Quercetin liposome administration significantly reduced the MDA content and increased SOD and GSH-PX activities in the lung tissues, and reduced the total cell counts and inflammatory cell proportions in the BALF, plasma TNF-α and TGF-β1 concentrations and the HP content in the lung tissues. A histological examination revealed suppression of the inflammatory response and reduced TGF-β1 expression and fibrosis scores. Radiation-induced oxidative damage ranged from pneumonitis to lung fibrosis. Quercetin liposomes were shown to protect against radiation-induced acute pneumonitis and late fibrosis, potentially by reducing oxidative damage. PMID:24137346

  18. Accumulation of radiation-induced charge in MNOS structures with different oxide thicknesses

    SciTech Connect

    Gurtov, V.A.; Evdokimov, V.D.; Nazarov, A.I.; Khrustalev, V.A.

    1986-05-01

    The authors attempt to answer questions regarding the dosimetry of x-ray radiation sources, especially in the region of high exposure doses, using silicon nitride. SiO/sub 2/ was obtained by thermal oxidation in dry oxygen or in a mixture of oxygen and argon. Silicon nitride was obtained by ammonolysis of silicon tetrachloride. Aluminum was used for the gate. The magnitude of the radiation-induced space charge was determined from the shift in the flat-band voltage on the high-frequency volt-faraday curves.

  19. Modification of radiation-induced oxidative damage in liposomal and microsomal membrane by eugenol

    NASA Astrophysics Data System (ADS)

    Pandey, B. N.; Lathika, K. M.; Mishra, K. P.

    2006-03-01

    Radiation-induced membrane oxidative damage, and their modification by eugenol, a natural antioxidant, was investigated in liposomes and microsomes. Liposomes prepared with DPH showed decrease in fluorescence after γ-irradiation, which was prevented significantly by eugenol and correlated with magnitude of oxidation of phospholipids. Presence of eugenol resulted in substantial inhibition in MDA formation in irradiated liposomes/microsomes, which was less effective when added after irradiation. Similarly, the increase in phospholipase C activity observed after irradiation in microsomes was inhibited in samples pre-treated with eugenol. Results suggest association of radio- oxidative membrane damage with alterations in signaling molecules, and eugenol significantly prevented these membrane damaging events.

  20. Observation of linear-polarization-sensitivity in the microwave-radiation-induced magnetoresistance oscillations

    SciTech Connect

    Mani, R. G.; Ramanayaka, A. N.; Wegscheider, W.

    2013-12-04

    We examine the linear polarization sensitivity of the radiation- induced magneto-resistance oscillations by investigating the effect of rotating in-situ the electric field of linearly polarized microwaves relative to the current, in the GaAs/AlGaAs system. We find that the frequency and the phase of the photo-excited magneto-resistance oscillations are insensitive to the polarization. On the other hand, the amplitude of the resistance oscillations are strongly sensitive to the relative orientation between the microwave antenna and the current-axis in the specimen.

  1. Resistance of radiation-induced tropical wood-polymer composites to fungal degradation

    NASA Astrophysics Data System (ADS)

    Chia, L. H. L.; Lim, V. S. L.; Yap, M. G. S.

    The resistance of six tropical hardwoods to fungal degradation by two wild-type strains of Phanerochaete chrysosporium Burdsall was investigated using vermiculite burial and wood-block weight loss techniques. Radiation-induced wood-polymer composites (WPC), based on two hardwoods Ramin and Rubber-wood with methyl methacrylate, were prepared, and samples were also exposed to the wood-rotting fungus. A significant improvement in resistance to fungal decay was observed in the WPC. Scanning-electron micrographs of the two woods and their composites after fungal degradation are presented and discussed.

  2. Altered Gastric Emptying and Prevention of Radiation-Induced Vomiting in Dogs

    DTIC Science & Technology

    1984-03-01

    nausea and vomiting is common10ily oh- of 10 dog$ pt’etrtolted wvith domperidone (p) < 0.01). served. These symptoms can occur after total body Gastric...Gastroenterol of radiotherapy-induced nausea and vomiting . Postgrad Med 1981;16(Suppl 67):33-6. 1979;55(Suppl 1):50-4. V.a, ...00_© 000 ’-- Altered gastric emptying and prevention of radiation-induced vomiting in dogs A. Dubois cc I J. P. Jacobus M. P. Grissom R.R. Eng J. J

  3. Radiation induced dechlorination of some chlorinated hydrocarbons in aqueous suspensions of various solid particles

    NASA Astrophysics Data System (ADS)

    Múčka, V.; Buňata, M.; Čuba, V.; Silber, R.; Juha, L.

    2015-07-01

    Radiation induced dechlorination of trichloroethylene (TCE) and tetrachloroethylene (PCE) in aqueous solutions containing the active carbon (AC) or cupric oxide (CuO) as the modifiers was studied. The obtained results were compared to the previously studied dechlorination of polychlorinated biphenyls (PCBs). Both modifiers were found to decrease the efficiency of dechlorination. The AC modifier acts mainly via adsorption of the aliphatic (unlike the aromatic) hydrocarbons and the CuO oxide mainly inhibits the mineralization of the perchloroethylene. The results presented in this paper will be also helpful for the studies of the impact of chlorinated hydrocarbons on the membrane permeability of living cells.

  4. Suppression of radiation-induced point defects by rhenium and osmium interstitials in tungsten

    NASA Astrophysics Data System (ADS)

    Suzudo, Tomoaki; Hasegawa, Akira

    2016-11-01

    Modeling the evolution of radiation-induced defects is important for finding radiation-resistant materials, which would be greatly appreciated in nuclear applications. We apply the density functional theory combined with comprehensive analyses of massive experimental database to indicate a mechanism to mitigate the effect of radiation on W crystals by adding particular solute elements that change the migration property of interstitials. The resultant mechanism is applicable to any body-centered-cubic (BCC) metals whose self-interstitial atoms become a stable crowdion and is expected to provide a general guideline for computational design of radiation-resistant alloys in the field of nuclear applications.

  5. About mechanisms of radiation-induced effect of nanostructurization of near-surface volumes of metals

    NASA Astrophysics Data System (ADS)

    Ivchenko, V. A.

    2017-01-01

    Mechanisms of the radiation-induced development of nanostructures in subsurface metal regions have been analyzed based on field-ion microscopy data. It is concluded that the modification of near-surface metal regions on a nanometer scale as a result of the interaction with Ar+ ion beams proceeds by several mechanisms. In particular, for a fluence of F = 1016 ion/cm2 (at an ion energy of E = 30 keV), the main contribution is due to the ion channeling. A tenfold increase in the ion fluence leads to prevailing deformation mechanism in nanostructure formation in the subsurface metal regions.

  6. Radiation-induced graft polymerization of acrylamide and acrylic acid onto polyethylene

    NASA Astrophysics Data System (ADS)

    Grushevskaya, L. N.; Aliev, R. E.; Kabanov, V. Ya.

    The radiation-induced grafting of acrylamide onto low-density polyethylene by the different methods and under different conditions was investigated: by the direct liquid phase method from this monomer solution in water (in neutral and acid media) and acetone, and by the pre-irradiation method from aqueous solutions as well as from its sublimated vapour. The molecular masses of polyacrylamide homopolymers were determined. The discussion and comparison of different methods of acrylamide grafting are performed. The relationship between rates of graft polymerization onto polyethylene and homopolymerization of acrylic acid in the presence of metal ions is considered.

  7. The influence of infrared radiation on short-term ultraviolet-radiation-induced injuries

    SciTech Connect

    Kaidbey, K.H.; Witkowski, T.A.; Kligman, A.M.

    1982-05-01

    Because heat has been reported to influence adversely short- and long-term ultraviolet (UV)-radiation-induced skin damage in animals, we investigated the short-term effects of infrared radiation on sunburn and on phototoxic reactions to topical methoxsalen and anthracene in human volunteers. Prior heating of the skin caused suppression of the phototoxic response to methoxsalen as evidenced by an increase in the threshold erythema dose. Heat administered either before or after exposure to UV radiation had no detectable influence on sunburn erythema or on phototoxic reactions provoked by anthracene.

  8. Radiation-Induced Cataractogenesis: A Critical Literature Review for the Interventional Radiologist

    SciTech Connect

    Seals, Kevin F. Lee, Edward W.; Cagnon, Christopher H.; Al-Hakim, Ramsey A. Kee, Stephen T.

    2016-02-15

    Extensive research supports an association between radiation exposure and cataractogenesis. New data suggests that radiation-induced cataracts may form stochastically, without a threshold and at low radiation doses. We first review data linking cataractogenesis with interventional work. We then analyze the lens dose typical of various procedures, factors modulating dose, and predicted annual dosages. We conclude by critically evaluating the literature describing techniques for lens protection, finding that leaded eyeglasses may offer inadequate protection and exploring the available data on alternative strategies for cataract prevention.

  9. Effect of G/M ratio on the radiation-induced degradation of sodium alginate

    NASA Astrophysics Data System (ADS)

    Şen, Murat; Rendevski, Stojan; Kavaklı, Pınar Akkaş; Sepehrianazar, Amir

    2010-03-01

    Radiation-induced degradation of sodium alginate (NaAlg) having different G/M ratios was investigated. NaAlg samples were irradiated with gamma rays in air at ambient temperature in the solid state at low dose rate. Change in their molecular weights was followed by size exclusion chromatography (SEC). Changes in their rheological properties and viscosity values as a function of temperature, shear rate and irradiation dose were also determined. Chain scission yields, G( S), and degradation rates were calculated. It was observed that G/M ratio was an important factor controlling the G( S) and degradation rate of sodium alginate.

  10. Effect of bentonite on radiation induced dissolution of UO2 in an aqueous system

    NASA Astrophysics Data System (ADS)

    Barreiro Fidalgo, Alexandre; Sundin, Sara; Jonsson, Mats

    2014-04-01

    In order to elucidate the impact of bentonite on the process of radiation induced oxidative dissolution of UO2 in an aqueous system, the dissolution of U(VI) and consumption of H2O2 over time has been studied. In addition, γ-irradiation experiments were performed to study a more relevant and complex system, serving as a comparison with the previously stated system. In both cases, the experiments revealed that the presence of bentonite in water could either delay or prevent in part the release of uranium to the environment. The cause is mainly attributed to the scavenging of radiolytic oxidants rather than to the adsorption of uranium onto bentonite.

  11. Reversal of gamma-radiation-induced leukemogenesis in mice by immunomodulation with thiabendazole and dinitrofluorobenzene

    SciTech Connect

    Elgebaly, S.A.; Barton, R.; Forouhar, F.

    1985-04-01

    The effect of thiabendazole (TBZ) and dinitrofluorobenzene (DNFB) on radiation-induced leukemogenesis was investigated in the C57BL/6 mouse model. Administration of TBZ-DNFB during, post, or during and post irradiation successfully blocked leukemogenesis, as indicated by the absence of leukemia blast cells in thymus and peripheral blood, as well as prevented thymic lymphoma. TBZ-DNFB treatment prevented the development of leukemia when studies were terminated both after 7 months of last irradiation (disease fully developed) and after 5 months of last irradiation (disease in the process of development). This TBZ-DNFB treatment also resulted in a significant increase in survival.

  12. Suppression of radiation-induced point defects by rhenium and osmium interstitials in tungsten

    PubMed Central

    Suzudo, Tomoaki; Hasegawa, Akira

    2016-01-01

    Modeling the evolution of radiation-induced defects is important for finding radiation-resistant materials, which would be greatly appreciated in nuclear applications. We apply the density functional theory combined with comprehensive analyses of massive experimental database to indicate a mechanism to mitigate the effect of radiation on W crystals by adding particular solute elements that change the migration property of interstitials. The resultant mechanism is applicable to any body-centered-cubic (BCC) metals whose self-interstitial atoms become a stable crowdion and is expected to provide a general guideline for computational design of radiation-resistant alloys in the field of nuclear applications. PMID:27824134

  13. Suppression of radiation-induced point defects by rhenium and osmium interstitials in tungsten.

    PubMed

    Suzudo, Tomoaki; Hasegawa, Akira

    2016-11-08

    Modeling the evolution of radiation-induced defects is important for finding radiation-resistant materials, which would be greatly appreciated in nuclear applications. We apply the density functional theory combined with comprehensive analyses of massive experimental database to indicate a mechanism to mitigate the effect of radiation on W crystals by adding particular solute elements that change the migration property of interstitials. The resultant mechanism is applicable to any body-centered-cubic (BCC) metals whose self-interstitial atoms become a stable crowdion and is expected to provide a general guideline for computational design of radiation-resistant alloys in the field of nuclear applications.

  14. [High-dose radiation-induced meningioma following prophylactic cranial irradiation for acute lymphoblastic leukaemia].

    PubMed

    Matsuda, Ryosuke; Nikaido, Yuji; Yamada, Tomonori; Mishima, Hideaki; Tamaki, Ryo

    2005-03-01

    A 12 year-old girl was treated with prophylatic cranial irradiation for acute lymphoblastic leukaemia (ALL). At the age of 39, she was admitted to our hospital for status epilepticus. Computed tomography demonstrated two, enhancing bilateral sided intracranial tumors. After surgery, this patient presented meningiomas which histologically, were of the meningothelial type. The high cure rate in childhood ALL, attributable to aggressive chemotherapy and prophylatic cranial irradiation, is capable of inducing secondary brain tumor. Twelve cases of high-dose radiation-induced meningioma following ALL are also reviewed.

  15. The effects of hyper velocity impact phenomena on radiation induced defects

    NASA Astrophysics Data System (ADS)

    Yamanaka, C.; Ikeya, M.

    1994-06-01

    Effects of high speed impacts on radiation-induced defects were investigated with a plasma rail-gun. Vitreous quartz targets irradiated by γ-ray were shocked with polycarbonate projectiles at a speed of 7 km/s, then the remaining destroyed pieces were examined by ESR spectroscopy to investigate the degree of "impact-annealing". The white substance from the impact point showed a trace of melting and no ESR signal, while the rest of the scattered pieces showed a decrease of E' center density to 50 ± 10% of the initial density. The defect production efficiency for the impacted silica was almost two-third of the original material.

  16. EPR study of radiation-induced radicals in glutaric and amino acid derivatives in solid state

    NASA Astrophysics Data System (ADS)

    Yeşim Dicle, Işık

    2015-05-01

    Gamma radiation-induced radicals of 2-methylglutaric acid (2MG), diethyl amino malonate hydrochloride (DEAMHCl), ethyl malonate monoamide have been investigated at room temperature by the electron paramagnetic resonance technique. The type of radicals formed and their room temperature stability were evaluated. Three different radicals have been detected. The free radicals formed in compounds were attributed to the HOOCCH3ĊCH2CH2 COOH, CH3ĊHCO2CHNH2COCH2CH3 HCl and NH2COCH2COOĊHCH3 radicals, respectively. The results were found to be in good agreement with the existing literature data and theoretical predictions conformation.

  17. Summary of round robin measurements of radiation induced conductivity in Wesgo AL995 alumina

    SciTech Connect

    Zinkle, S.J.

    1996-10-01

    This existing data on radiation induced conductivity (RIC) measurements performed on the same heat of the IEA reference ceramic insulator are summarized. Six different sets of RIC measurements have been performed on Wesgo AL995 at dose rates between 10 Gy/s and 1 MGy/s. In general, good agreement was obtained between the different groups of researchers. The data indicate that the RIC at a test temperature of 400-500{degrees}C is approximately linear with ionizing dose rate up to {approximately}1000 Gy/s, and exhibits an approximately square root dependence on dose rate between 1 kGy/s and 1 MGy/s.

  18. Radiation-Induced Leiomyosarcoma after Breast Cancer Treatment and TRAM Flap Reconstruction

    PubMed Central

    Olcina, M.; Merck, B.; Giménez-Climent, M. J.; Almenar, S.; Sancho-Merle, M. F.; Llopis, F.; Vázquez-Albadalejo, C.

    2008-01-01

    The development of a radiation-induced sarcoma (RIS) in the post mastectomy thoracic treatment volume is an infrequent, but recognized, event. Its frequency is rising in relation with increasing survival of breast cancer patients treated with adjuvant radiation therapy, and is associated with poor prognosis despite treatment. We present a case of leiomyosarcoma in a patient who underwent mastectomy followed by radiotherapy for invasive ductal carcinoma. A delayed TRAM flap reconstruction was performed 10 years after and a rapid growing mass under the reconstructed flap appeared, on routine follow-up, twenty years later. This report analyzes the diagnostic and therapeutic approach of patients with RIS. PMID:18464918

  19. Tetrahydrobiopterin Protects against Radiation-induced Growth Inhibition in H9c2 Cardiomyocytes

    PubMed Central

    Zhang, Zheng-Yi; Li, Yi; Li, Rui; Zhang, An-An; Shang, Bo; Yu, Jing; Xie, Xiao-Dong

    2016-01-01

    Background: Tetrahydrobiopterin (BH4) is an essential cofactor of nitric oxide synthases (NOSs) for the synthesis of nitric oxide (NO). BH4 therapy can reverse the disease-related redox disequilibrium observed with BH4 deficiency. However, whether BH4 exerts a protective effect against radiation-induced damage to cardiomyocytes remains unknown. Methods: Clonogenic assays were performed to determine the effects of X-ray on H9c2 cells with or without BH4 treatment. The contents of lactate dehydrogenase (LDH), superoxide dismutase (SOD), and malondialdehyde (MDA) in H9c2 cells were measured to investigate oxidative stress levels. The cell cycle undergoing radiation with or without BH4 treatment was detected using flow cytometry. The expression levels of proteins in the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT)/P53 signaling pathway, inducible NOS (iNOS), and endothelial NOS (eNOS) were examined using Western blotting. Results: X-ray radiation significantly inhibited the growth of H9c2 cells in a dose-dependent manner, whereas BH4 treatment significantly reduced the X-ray radiation-induced growth inhibition (control group vs. X-ray groups, respectively, P < 0.01). X-ray radiation induced LDH release, apoptosis, and G0/G1 peak accumulation, significantly increasing the level of MDA and the production of NO, and decreased the level of SOD (control group vs. X-ray groups, respectively, P < 0.05 or P < 0.01). By contrast, BH4 treatment can significantly reverse these processes (BH4 treatment groups vs. X-ray groups, P < 0.05 or P < 0.01). BH4 reversed the X-ray radiation-induced expression alterations of apoptosis-related molecules, including B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein, and caspase-3, and molecules of the PI3K/Akt/P53 signaling pathway. BH4 enhanced the production of NO in 2 Gy and 4 Gy radiated groups by upregulating eNOS protein expression and downregulating iNOS protein expression. Conclusions: BH4 treatment can protect

  20. Radiation induced failures of complementary metal oxide semiconductor containing pacemakers: a potentially lethal complication

    SciTech Connect

    Lewin, A.A.; Serago, C.F.; Schwade, J.G.; Abitbol, A.A.; Margolis, S.C.

    1984-10-01

    New multi-programmable pacemakers frequently employ complementary metal oxide semiconductors (CMOS). This circuitry appears more sensitive to the effects of ionizing radiation when compared to the semiconductor circuits used in older pacemakers. A case of radiation induced runaway pacemaker in a CMOS device is described. Because of this and other recent reports of radiation therapy-induced CMOS type pacemaker failure, these pacemakers should not be irradiated. If necessary, the pacemaker can be shielded or moved to a site which can be shielded before institution of radiation therapy. This is done to prevent damage to the CMOS circuit and the life threatening arrythmias which may result from such damage.

  1. Protective effects of L-selenomethionine on space radiation induced changes in gene expression.

    PubMed

    Stewart, J; Ko, Y-H; Kennedy, A R

    2007-06-01

    Ionizing radiation can produce adverse biological effects in astronauts during space travel. Of particular concern are the types of radiation from highly energetic, heavy, charged particles known as HZE particles. The aims of our studies are to characterize HZE particle radiation induced biological effects and evaluate the effects of L-selenomethionine (SeM) on these adverse biological effects. In this study, microarray technology was used to measure HZE radiation induced changes in gene expression, as well as to evaluate modulation of these changes by SeM. Human thyroid epithelial cells (HTori-3) were irradiated (1 GeV/n iron ions) in the presence or in the absence of 5 microM SeM. At 6 h post-irradiation, all cells were harvested for RNA isolation. Gene Chip U133Av2 from Affymetrix was used for the analysis of gene expression, and ANOVA and EASE were used for a determination of the genes and biological processes whose differential expression is statistically significant. Results of this microarray study indicate that exposure to small doses of radiation from HZE particles, 10 and 20 cGy from iron ions, induces statistically significant differential expression of 196 and 610 genes, respectively. In the presence of SeM, differential expression of 77 out of 196 genes (exposure to 10 cGy) and 336 out of 610 genes (exposure to 20 cGy) is abolished. In the presence or in the absence of SeM, radiation from HZE particles induces differential expression of genes whose products have roles in the induction of G1/S arrest during the mitotic cell cycle, as well as heat shock proteins. Some of the genes, whose expressions were affected by radiation from HZE particles and were unchanged in irradiated cells treated with SeM, have been shown to have altered expression levels in cancer cells. The conclusions of this report are that radiation from HZE particles can induce differential expression of many genes, some of which are known to play roles in the same processes that have

  2. Radiation-induced cholecystitis after hepatic radioembolization: do we need to take precautionary measures?

    PubMed

    Prince, Jip F; van den Hoven, Andor F; van den Bosch, Maurice A A J; Elschot, Mattijs; de Jong, Hugo W A M; Lam, Marnix G E H

    2014-11-01

    Controversy exists over the need to take precautionary measures during hepatic radioembolization to minimize the risk of radiation-induced cholecystitis. Strategies for a variety of clinical scenarios are discussed on the basis of a literature review. Precautionary measures are unnecessary in the majority of patients and should be taken only when single photon-emission computed tomography (CT; SPECT)/CT shows a significant concentration of technetium-99m macroaggregated albumin in the gallbladder wall. In this case report with quantitative SPECT analysis, it is illustrated how an adjustment of the catheter position can effectively reduce the absorbed dose of radiation delivered to the gallbladder wall by more than 90%.

  3. Radiation-Induced Reduction of Ceria in Single and Polycrystalline Thin Films

    SciTech Connect

    Kumar, Amit; Devanathan, Ramaswami; Shutthanandan, V.; Kuchibhatla, Satyanarayana V N T; Karakoti, Ajay S.; Yang, Yong; Thevuthasan, Suntharampillai; Seal, Sudipta

    2012-01-12

    Ceria (CeO{sub 2}) is a technologically important ceramic material with a wide range of neoteric applications in catalysis, solid oxide fuel cells, oxygen gas sensors, hydrogen production, and ultraviolet shielding. Recent research has revealed promising biomedical applications of ceria. Nanoparticles of ceria have been shown to protect healthy cells from radiation-induced cellular damage. The mechanisms governing the radioprotection characteristics of ceria nanoparticles are not well understood and it has been hypothesized that reversible switching between Ce{sup 4+} and Ce{sup 3+} states may enable ceria nanoparticles to mop up free radicals.

  4. MRI of the Brachial Plexus: Modified Imaging Technique Leading to a Better Characterization of Its Anatomy and Pathology

    PubMed Central

    Torres, Carlos; Mailley, Kathleen; del Carpio O’Donovan, Raquel

    2013-01-01

    Summary Magnetic resonance imaging (MRI) is the imaging modality of choice for the evaluation of the brachial plexus due to its superior soft tissue resolution and multiplanar capabilities. The evaluation of the brachial plexus however represents a diagnostic challenge for the clinician and the radiologist. The imaging assessment of the brachial plexus, in particular, has been traditionally challenging due to the complexity of its anatomy, its distribution in space and due to technical factors. Herein, we describe a modified technique used in our institution for the evaluation of the brachial plexus which led to a substantial decrease in scanning time and to better visualization of all the segments of the brachial plexus from the roots to the branches, in only one or two images, facilitating therefore the understanding of the anatomy and the interpretation of the study. To our knowledge, we are the first group to describe this technique of imaging the brachial plexus. We illustrate the benefit of this modified technique with an example of a patient with a lesion in the proximal branches of the left brachial plexus that was clinically suspected but missed on conventional brachial plexus imaging for six consecutive years. In addition, we review the common and infrequent benign and malignant pathology that can affect the brachial plexus. PMID:24355190

  5. Brachial artery injury following opened elbow dislocation associated with accessory brachial artery: two rare entities in a 17-year -old girl: case report.

    PubMed

    Hajji, Rita; Zrihni, Youssef; Naouli, Hamza; Bouarhroum, Abdellatif

    2015-01-01

    Elbow dislocations are the most frequently encountered after shoulder dislocations. In their vast majority, these injuries carry a good prognosis. Although, concomitant arterial injury is rare and make them more serious. In this paper, we report a case of a 17 year old woman with opened elbow dislocation with arterial injury associated to an artery variation: "accessory brachial artery".

  6. Brachial artery injury following opened elbow dislocation associated with accessory brachial artery: two rare entities in a 17-year –old girl: case report

    PubMed Central

    Hajji, Rita; Zrihni, Youssef; Naouli, Hamza; Bouarhroum, Abdellatif

    2015-01-01

    Elbow dislocations are the most frequently encountered after shoulder dislocations. In their vast majority, these injuries carry a good prognosis. Although, concomitant arterial injury is rare and make them more serious. In this paper, we report a case of a 17 year old woman with opened elbow dislocation with arterial injury associated to an artery variation: "accessory brachial artery" PMID:26161188

  7. MiR-21 is involved in radiation-induced bystander effects.

    PubMed

    Xu, Shuai; Ding, Nan; Pei, Hailong; Hu, Wentao; Wei, Wenjun; Zhang, Xurui; Zhou, Guangming; Wang, Jufang

    2014-01-01

    Radiation-induced bystander effects are well-established phenomena, in which DNA damage responses are induced not only in the directly irradiated cells but also in the non-irradiated bystander cells through intercellular signal transmission. Recent studies hint that bystander effects are possibly mediated via small non-coding RNAs, especially microRNAs. Thus, more details about the roles of microRNA in bystander effects are urgently needed to be elucidated. Here we demonstrated that bystander effects were induced in human fetal lung MRC-5 fibroblasts through medium-mediated way by different types of radiation. We identified a set of differentially expressed microRNAs in the cell culture medium after irradiation, among which the up-regulation of miR-21 was further verified with qRT-PCR. In addition, we found significant upregulation of miR-21 in both directly irradiated cells and bystander cells, which was confirmed by the expression of miR-21 precursor and its target genes. Transfection of miR-21 mimics into non-irradiated MRC-5 cells caused bystander-like effects. Taken together, our data reveals that miR-21 is involved in radiation-induced bystander effects. Elucidation of such a miRNA-mediated bystander effect is of utmost importance in understanding the biological processes related to ionizing radiation and cell-to-cell communication.

  8. Protective effect of mild endoplasmic reticulum stress on radiation-induced bystander effects in hepatocyte cells.

    PubMed

    Xie, Yuexia; Ye, Shuang; Zhang, Jianghong; He, Mingyuan; Dong, Chen; Tu, Wenzhi; Liu, Peifeng; Shao, Chunlin

    2016-12-13

    Radiation-induced bystander effect (RIBE) has important implications for secondary cancer risk assessment during cancer radiotherapy, but the defense and self-protective mechanisms of bystander normal cells are still largely unclear. The present study found that micronuclei (MN) formation could be induced in the non-irradiated HL-7702 hepatocyte cells after being treated with the conditioned medium from irradiated hepatoma HepG2 cells under either normoxia or hypoxia, where the ratio of the yield of bystander MN induction to the yield of radiation-induced MN formation under hypoxia was much higher than that of normoxia. Nonetheless, thapsigargin induced endoplasmic reticulum (ER) stress and dramatically suppressed this bystander response manifested as the decrease of MN and apoptosis inductions. Meanwhile, the interference of BiP gene, a major ER chaperone, amplified the detrimental RIBE. More precisely, thapsigargin provoked ER sensor of PERK to initiate an instantaneous and moderate ER stress thus defensed the hazard form RIBE, while BiP depletion lead to persistently destroyed homeostasis of ER and exacerbated cell injury. These findings provide new insights that the mild ER stress through BiP-PERK-p-eIF2α signaling pathway has a profound role in protecting cellular damage from RIBE and hence may decrease the potential secondary cancer risk after cancer radiotherapy.

  9. The role of protein kinase C alpha translocation in radiation-induced bystander effect.

    PubMed

    Fang, Zihui; Xu, An; Wu, Lijun; Hei, Tom K; Hong, Mei

    2016-05-11

    Ionizing radiation is a well known human carcinogen. Evidence accumulated over the past decade suggested that extranuclear/extracellular targets and events may also play a critical role in modulating biological responses to ionizing radiation. However, the underlying mechanism(s) of radiation-induced bystander effect is still unclear. In the current study, AL cells were irradiated with alpha particles and responses of bystander cells were investigated. We found out that in bystander AL cells, protein kinase C alpha (PKCα) translocated from cytosol to membrane fraction. Pre-treatment of cells with PKC translocation inhibitor chelerythrine chloride suppressed the induced extracellular signal-regulated kinases (ERK) activity and the increased cyclooxygenase 2 (COX-2) expression as well as the mutagenic effect in bystander cells. Furthermore, tumor necrosis factor alpha (TNFα) was elevated in directly irradiated but not bystander cells; while TNFα receptor 1 (TNFR1) increased in the membrane fraction of bystander cells. Further analysis revealed that PKC activation caused accelerated internalization and recycling of TNFR1. Our data suggested that PKCα translocation may occur as an early event in radiation-induced bystander responses and mediate TNFα-induced signaling pathways that lead to the activation of ERK and up-regulation of COX-2.

  10. Exosome-mediated microRNA transfer plays a role in radiation-induced bystander effect.

    PubMed

    Xu, Shuai; Wang, Jufang; Ding, Nan; Hu, Wentao; Zhang, Xurui; Wang, Bing; Hua, Junrui; Wei, Wenjun; Zhu, Qiyun

    2015-01-01

    Bystander effects can be induced through cellular communication between irradiated cells and non-irradiated cells. The signals that mediate this cellular communication, such as cytokines, reactive oxygen species, nitric oxide and even microRNAs, can be transferred between cells via gap junctions or extracellular medium. We have previously reported that miR-21, a well described DDR (DNA damage response) microRNA, is involved in radiation-induced bystander effects through a medium-mediated way. However, the mechanisms of the microRNA transfer have not been elucidated in details. In the present study, it was found that exosomes isolated from irradiated conditioned medium could induce bystander effects. Furthermore, we demonstrated plenty of evidences that miR-21, which is up-regulated as a result of mimic transfection or irradiation, can be transferred from donor or irradiated cells into extracellular medium and subsequently get access to the recipient or bystander cells through exosomes to induce bystander effects. Inhibiting the miR-21 expression in advance can offset the bystander effects to some extent. From all of these results, it can be concluded that the exosome-mediated microRNA transfer plays an important role in the radiation-induced bystander effects. These findings provide new insights into the functions of microRNAs and the cellular communication between the directly irradiated cells and the non-irradiated cells.

  11. The study of radiation induced DNA-protein crosslinks by electrospray ionization mass spectrometry

    SciTech Connect

    Lipton, M.S.; Fuciarelli, A.F.; Springer, D.L.; Edmonds, C.G.

    1995-12-31

    The authors have used peptide-thymine and histone-thymine solutions to model protein-DNA cross-linking chemistry induced in intact chromatin by low dosage of g-irradiation. Induced thymine crosslinking to model peptide systems has been evaluated by on-line liquid chromatography-electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (MS-MS) with sensitivity comparable or superior to conventional GC-MS determinations. Radiation damage at doses as low as 0.1 Gy can be detected by this method. Additionally, thymine modified H2B can also be examined by ESI-MS and tandem-MS of the intact protein and proteinase digests. Limited information on the sites of thymine crosslinking can be obtained by tandem mass spectrometry on the intact multiply charged molecular species. More detailed information on the sites of thymine-protein crosslinking is obtained by on-line LC-ESI-MS of selective proteolysis products of the modified histones. Further MS-MS experiments on the selective proteolysis products will reveal specific modified amino acids and their sequence location. These methods reveal the nature, extent and site of radiation induced modification of the oligopeptides. Studies are being extended to the examination of the radiation induced covalent interactions between histones and oligonucleotides in higher states of organization. The eventual object is to study DNA-protein crosslinking interactions in model and native genomic nucleosome systems.

  12. Silencing of Cited2 and Akap12 genes in radiation-induced rat osteosarcomas

    SciTech Connect

    Daino, Kazuhiro

    2009-12-18

    We have previously studied genomic copy number changes and global gene expression patterns in rat osteosarcomas (OS) induced by the bone-seeking alpha emitter {sup 238}Pu by comparative genomic hybridization (CGH) and oligonucleotide microarray analyses, respectively. Among the previously identified genes that were down-regulated in radiation-induced rat OS tumors, Cited2 (Cbp/p300-interacting transactivator, with Glu/Asp-rich carboxy-terminal domain, 2) and Akap12 (a kinase anchoring protein, also known as src-suppressed C-kinase substrate, SSeCKS) genes mapped to the most frequently lost regions on chromosome 1p. In the present study, relative copy number losses of Cited2 and Akap12 genes were observed in 8 of 15 (53%) and 10 of 15 (67%) tumors by quantitative PCR analysis. Loss of Cited2 and Akap12 in the tumors was confirmed at the levels of mRNA and protein expression by quantitative RT-PCR and immunoblot analyses, respectively. These results indicate that Cited2 and Akap12 are silenced in radiation-induced OS, and therefore are novel candidate tumor-suppressor genes of this tumor.

  13. Does altered fractionation influence the risk of radiation-induced optic neuropathy?

    SciTech Connect

    Bhandare, Niranjan; Monroe, Alan T.; Morris, Christopher G.; Bhatti, M. Tariq; Mendenhall, William M. . E-mail: mendewil@shands.ufl.edu

    2005-07-15

    Purpose: To analyze the parameters that influence the risk of radiation-induced optic neuropathy (RION) after radiotherapy for head-and-neck tumors. Methods and Materials: Between 1964 and 2000, 273 patients with tumors of the nasopharynx, paranasal sinuses, nasal cavity, and hard palate adenoid cystic carcinomas were treated with curative intent and had radiation fields that included the optic nerves and/or chiasm. Patients were followed for at least 1 year after radiotherapy. Results: Radiation-induced optic neuropathy developed in 32 eyes of 24 patients (9%). The 5-year rates of freedom from RION according to the total dose and once- vs. twice-daily fractionation were as follows: {<=}63 Gy once daily, 95%; {<=}63 Gy twice daily, 98%; >63 Gy once daily, 78%; and >63 Gy twice daily, 91%. Multivariate analysis revealed that the total dose affected the risk of RION (p = 0.0047), with patient age (p = 0.0909), once-daily vs. twice-daily fractionation (p = 0.0684), and overall treatment time (p = 0.0972) were marginally significant. The use of adjuvant chemotherapy did not significantly influence the likelihood of developing RION. Conclusion: The likelihood of developing RION is primarily influenced by the total dose. Hyperfractionation may reduce the risk of experiencing this complication.

  14. Radiofrequency radiation-induced calcium ion efflux enhancement from human and other neuroblastoma cells in culture

    SciTech Connect

    Dutta, S.K.; Ghosh, B.; Blackman, C.F.

    1989-01-01

    To test the generality of radiofrequency radiation-induced changes in /sup 45/Ca2+ efflux from avian and feline brain tissues, human neuroblastoma cells were exposed to electromagnetic radiation at 147 MHz, amplitude-modulated (AM) at 16 Hz, at specific absorption rates (SAR) of 0.1, 0.05, 0.01, 0.005, 0.001, and 0.0005 W/kg. Significant /sup 45/Ca2+ efflux was obtained at SAR values of 0.05 and 0.005 W/kg. Enhanced efflux at 0.05 W/kg peaked at the 13-16 Hz and at the 57.5-60 Hz modulation ranges. A Chinese hamster-mouse hybrid neuroblastoma was also shown to exhibit enhanced radiation-induced /sup 45/Ca2+ efflux at an SAR of 0.05 W/kg, using 147 MHz, AM at 16 Hz. These results confirm that amplitude-modulated radiofrequency radiation can induce responses in cells of nervous tissue origin from widely different animal species, including humans. The results are also consistent with the reports of similar findings in avian and feline brain tissues and indicate the general nature of the phenomenon.

  15. Radiation-induced complications in prostate cancer patients treated with radiotherapy

    NASA Astrophysics Data System (ADS)

    Azuddin, A. Yusof; Rahman, I. Abdul; Siah, N. J.; Mohamed, F.; Saadc, M.; Ismail, F.

    2014-09-01

    The purpose of the study is to determine the relationship between radiation-induced complications with dosimetric and radiobiological parameters for prostate cancer patients that underwent the conformal radiotherapy treatment. 17 prostate cancer patients that have been treated with conformal radiotherapy were retrospectively analysed. The dosimetric data was retrieved in the form of dose-volume histogram (DVH) from Radiotherapy Treatment Planning System. The DVH was utilised to derived Normal Tissue Complication Probability (NTCP) in radiobiological data. Follow-up data from medical records were used to grade the occurrence of acute gastrointestinal (GI) and genitourinary (GU) complications using Radiation Therapy Oncology Group (RTOG) scoring system. The chi-square test was used to determine the relationship between radiation-induced complication with dosimetric and radiobiological parameters. 8 (47%) and 7 (41%) patients were having acute GI and GU complications respectively. The acute GI complication can be associated with V60rectum, rectal mean dose and NTCPrectum with p-value of 0.016, 0.038 and 0.049 respectively. There are no significant relationships of acute GU complication with dosimetric and radiobiological variables. Further study can be done by increase the sample size and follow up duration for deeper understanding of the factors that effecting the GU and GI complication in prostate cancer radiotherapy.

  16. Prevention effects of Schisandra polysaccharide on radiation-induced immune system dysfunction.

    PubMed

    Zhao, Lian-Mei; Jia, Yun-Long; Ma, Ming; Duan, Yu-Qing; Liu, Li-Hua

    2015-05-01

    In this study, we investigate the efficacy of SP (Schisandra polysaccharide) in prevention of radiation-induced immune dysfunction and discussed the underlying mechanisms with a Bal/bc mouse model. The data demonstrated that SP could reverse the decreases in the number of white blood cells and lymphocytes in peripheral blood. In addition, the immunoglobulin G (IgG) and complement C3 in blood serum were all decreased after radiation and SP could restore this radiation disorder. Furthermore, SP could reverse the deregulation of CD3(+)CD4(+) and CD3(+)CD8(+) T cell subsets in peripheral blood and thymus of mice after radiotherapy. We also performed terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) and Immunohistochemistry (IHC) to investigate the apoptosis and underlying mechanisms of SP in thymus. Data showed that radiation-induced apoptosis of thymocytes could be reversed by SP through inducing upregulation of Bcl-2 expression and downregulation of Fas and Bax levels. Furthermore, SP has no any side-effects on immunity of normal mice. In conclusion, our results indicated that SP could effectively prevent immune injury during radiotherapy by protecting the immune system. This valuable information should be of assistance in choosing a rational design for therapeutic interventions of prevention immune system damage in the radiation treatment.

  17. Ozone Therapy in the Management of Persistent Radiation-Induced Rectal Bleeding in Prostate Cancer Patients.

    PubMed

    Clavo, Bernardino; Santana-Rodriguez, Norberto; Llontop, Pedro; Gutierrez, Dominga; Ceballos, Daniel; Méndez, Charlin; Rovira, Gloria; Suarez, Gerardo; Rey-Baltar, Dolores; Garcia-Cabrera, Laura; Martínez-Sánchez, Gregorio; Fiuza, Dolores

    2015-01-01

    Introduction. Persistent radiation-induced proctitis and rectal bleeding are debilitating complications with limited therapeutic options. We present our experience with ozone therapy in the management of such refractory rectal bleeding. Methods. Patients (n = 12) previously irradiated for prostate cancer with persistent or severe rectal bleeding without response to conventional treatment were enrolled to receive ozone therapy via rectal insufflations and/or topical application of ozonized-oil. Ten (83%) patients had Grade 3 or Grade 4 toxicity. Median follow-up after ozone therapy was 104 months (range: 52-119). Results. Following ozone therapy, the median grade of toxicity improved from 3 to 1 (p < 0.001) and the number of endoscopy treatments from 37 to 4 (p = 0.032). Hemoglobin levels changed from 11.1 (7-14) g/dL to 13 (10-15) g/dL, before and after ozone therapy, respectively (p = 0.008). Ozone therapy was well tolerated and no adverse effects were noted, except soft and temporary flatulence for some hours after each session. Conclusions. Ozone therapy was effective in radiation-induced rectal bleeding in prostate cancer patients without serious adverse events. It proved useful in the management of rectal bleeding and merits further evaluation.

  18. Ozone Therapy in the Management of Persistent Radiation-Induced Rectal Bleeding in Prostate Cancer Patients

    PubMed Central

    Clavo, Bernardino; Santana-Rodriguez, Norberto; Llontop, Pedro; Gutierrez, Dominga; Ceballos, Daniel; Méndez, Charlin; Rovira, Gloria; Suarez, Gerardo; Rey-Baltar, Dolores; Garcia-Cabrera, Laura; Martínez-Sánchez, Gregorio; Fiuza, Dolores

    2015-01-01

    Introduction. Persistent radiation-induced proctitis and rectal bleeding are debilitating complications with limited therapeutic options. We present our experience with ozone therapy in the management of such refractory rectal bleeding. Methods. Patients (n = 12) previously irradiated for prostate cancer with persistent or severe rectal bleeding without response to conventional treatment were enrolled to receive ozone therapy via rectal insufflations and/or topical application of ozonized-oil. Ten (83%) patients had Grade 3 or Grade 4 toxicity. Median follow-up after ozone therapy was 104 months (range: 52–119). Results. Following ozone therapy, the median grade of toxicity improved from 3 to 1 (p < 0.001) and the number of endoscopy treatments from 37 to 4 (p = 0.032). Hemoglobin levels changed from 11.1 (7–14) g/dL to 13 (10–15) g/dL, before and after ozone therapy, respectively (p = 0.008). Ozone therapy was well tolerated and no adverse effects were noted, except soft and temporary flatulence for some hours after each session. Conclusions. Ozone therapy was effective in radiation-induced rectal bleeding in prostate cancer patients without serious adverse events. It proved useful in the management of rectal bleeding and merits further evaluation. PMID:26357522

  19. Radiation-induced genomic instability: Are epigenetic mechanisms the missing link?

    SciTech Connect

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

    2011-02-01

    Purpose: This review examines the evidence for the hypothesis that epigenetics are involved in the initiation and perpetuation of radiation-induced genomic instability (RIGI). Conclusion: In addition to the extensively studied targeted effects of radiation, it is now apparent that non-targeted delayed effects such as RIGI are also important post-irradiation outcomes. In RIGI, unirradiated progeny cells display phenotypic changes at delayed times after radiation of the parental cell. RIGI is thought to be important in the process of carcinogenesis, however, the mechanism by which this occurs remains to be elucidated. In the genomically unstable clones developed by Morgan and colleagues, radiation-induced mutations, double-strand breaks, or changes in mRNA levels alone could not account for the initiation or perpetuation of RIGI. Since changes in the DNA sequence could not fully explain the mechanism of RIGI, inherited epigenetic changes may be involved. Epigenetics are known to play an important role in many cellular processes and epigenetic aberrations can lead to carcinogenesis. Recent studies in the field of radiation biology suggest that the changes in methylation patterns may be involved in RIGI. Together these clues have led us to hypothesize that epigenetics may be the missing link in understanding the mechanism behind RIGI.

  20. Radiation-Induced Testicular Injury and Its Amelioration by Tinospora cordifolia (An Indian Medicinal Plant) Extract

    PubMed Central

    Sharma, Priyanka; Parmar, Jyoti; Sharma, Priyanka; Verma, Preeti; Goyal, P. K.

    2011-01-01

    The primary objective of this investigation is to determine the deleterious effects of sub lethal gamma radiation on testes and their possible inhibition by Tinospora cordifolia extract (TCE). For this purpose, one group of male Swiss albino mice was exposed to 7.5 Gy gamma radiation to serve as the irradiated control, while the other group received TCE (75 mg/kg b. wt./day) orally for 5 consecutive days half an hr before irradiation to serve as experimental. Exposure of animals to 7.5 Gy gamma radiation resulted into significant decrease in body weight, tissue weight, testes- body weight ratio and tubular diameter up to 15 days of irradiation. Cent percent mortality was recorded by day 17th in irradiated control, whereas all animals survived in experimental group. TCE pretreatment rendered significant increase in body weight, tissue weight, testes- body weight ratio and tubular diameter at various intervals as compared to irradiated group. Radiation induced histological lesions in testicular architecture were observed more severe in irradiated control then the experimental. TCE administration before irradiation significantly ameliorated radiation induced elevation in lipid peroxidation and decline in glutathione concentration in testes. These observations indicate the radio- protective potential of Tinospora cordifolia root extract in testicular constituents against gamma irradiation in mice. PMID:21350610

  1. Antihistamines block radiation-induced increased intestinal blood flow in canines

    SciTech Connect

    Cockerham, L.G.; Doyle, T.F.; Donlon, M.A.; Gossett-Hagerman, C.J.

    1985-01-01

    Radiation-induced systemic hypotension is accompanied by increased intestinal blood flow (IBF) and an increased hematocrit (HCT) in dogs. Histamine infusion leads to increased IBF and intestinal edema with consequent secretion of fluid into the intestinal lumen. This study was performed to determine whether these effects could be diminished by prior administration of H/sub 1/ and H/sub 2/ histamine blockers. Dogs were given an iv infusion of mepyramine (0.5 mg/min) and cimetidine (0.25 mg/min) for 1 hr before and for 1 hr after radiation (H sub 1 and H sub 2 blockers, respectively). Mean systemic arterial blood pressure (MBP), IBF, and HCT were monitored for 2 hr. Systematic plasma histamine levels were determined simultaneously. Data obtained indicated that the H sub 1 and H sub 2 blockers, given simultaneously, were successful in blocking the increased IBF and the increased HCT seen after 100 Gy, whole-body, gamma radiation. However, the postradiation hypotension was only somewhat affected, with the MBP falling to a level 28% below the preradiation level. Plasma histamine levels reached a sharp peak, as much as 20% above baseline, at 4 min postradiation. These findings implicate histamine in the radiation-induced increase in IBF and HCT but not for the gradual decrease in postradiation blood pressure. (Author)

  2. Antihistamines block radiation-induced increased intestinal blood flow in canines

    SciTech Connect

    Cockerham, L.G.; Doyle, T.F.; Donlon, M.A.; Gossett-Hagerman, C.J.

    1985-06-01

    Radiation-induced systemic hypotension is accompanied by increased intestinal blood flow (IBF) and an increased hematocrit (HCT) in dogs. Histamine infusion leads to increased IBF and intestinal edema with consequent secretion of fluid into the intestinal lumen. This study was performed to determine whether these effects could be diminished by prior administration of H1 and H2 histamine blockers. Dogs were given an iv infusion of mepyramine (0.5 mg/min) and cimetidine (0.25 mg/min) for 1 hr before and for 1 hr after radiation (H1 and H2 blockers, respectively). Mean systemic arterial blood pressure (MBP), IBF, and HCT were monitored for 2 hr. Systemic plasma histamine levels were determined simultaneously. Data obtained indicated that the H1 and H2 blockers, given simultaneously, were successful in blocking the increased IBF and the increased HCT seen after 100 Gy, whole-body, gamma radiation. However, the postradiation hypotension was only somewhat affected, with the MBP falling to a level 28% below the preradiation level. Plasma histamine levels reached a sharp peak, as much as 20% above baseline, at 4 min postradiation. These findings implicate histamine in the radiation-induced increase in IBF and HCT but not for the gradual decrease in postradiation blood pressure.

  3. PHD Inhibition Mitigates and Protects Against Radiation-Induced Gastrointestinal Toxicity via HIF2

    PubMed Central

    Taniguchi, Cullen M.; Miao, Yu Rebecca; Diep, Anh N.; Wu, Colleen; Rankin, Erinn B.; Atwood, Todd F.; Xing, Lei; Giaccia, Amato J.

    2014-01-01

    Radiation-induced gastrointestinal (GI) toxicity can be a major source of morbidity and mortality after radiation exposure. There is an unmet need for effective preventative or mitigative treatments against the potentially fatal diarrhea and water loss induced by radiation damage to the GI tract. We report that prolyl hydroxylase inhibition by genetic knockout or pharmacologic inhibition of all PHD isoforms by the small molecule dimethyloxyallylglycine (DMOG) increases HIF expression, improves epithelial integrity, reduces apoptosis, and increases intestinal angiogenesis, all of which are essential for radioprotection. HIF2, but not HIF1, is both necessary and sufficient to prevent radiation-induced GI toxicity and death. Increased VEGF expression contributes to the protective effects of HIF2, since inhibition of VEGF function reversed the radioprotection and radiomitigation afforded by DMOG. Additionally, mortality is reduced from abdominal or total body irradiation even when DMOG is given 24 hours after exposure. Thus, prolyl hydroxylase inhibition represents a new treatment strategy to protect against and mitigate GI toxicity from both therapeutic radiation and potentially lethal radiation exposures. PMID:24828078

  4. Blockade of TLR3 protects mice from lethal radiation-induced gastrointestinal syndrome

    PubMed Central

    Takemura, Naoki; Kawasaki, Takumi; Kunisawa, Jun; Sato, Shintaro; Lamichhane, Aayam; Kobiyama, Kouji; Aoshi, Taiki; Ito, Junichi; Mizuguchi, Kenji; Karuppuchamy, Thangaraj; Matsunaga, Kouta; Miyatake, Shoichiro; Mori, Nobuko; Tsujimura, Tohru; Satoh, Takashi; Kumagai, Yutaro; Kawai, Taro; Standley, Daron M.; Ishii, Ken J.; Kiyono, Hiroshi; Akira, Shizuo; Uematsu, Satoshi

    2014-01-01

    High-dose ionizing radiation induces severe DNA damage in the epithelial stem cells in small intestinal crypts and causes gastrointestinal syndrome (GIS). Although the tumour suppressor p53 is a primary factor inducing death of crypt cells with DNA damage, its essential role in maintaining genome stability means inhibiting p53 to prevent GIS is not a viable strategy. Here we show that the innate immune receptor Toll-like receptor 3 (TLR3) is critical for the pathogenesis of GIS. Tlr3−/− mice show substantial resistance to GIS owing to significantly reduced radiation-induced crypt cell death. Despite showing reduced crypt cell death, p53-dependent crypt cell death is not impaired in Tlr3−/− mice. p53-dependent crypt cell death causes leakage of cellular RNA, which induces extensive cell death via TLR3. An inhibitor of TLR3–RNA binding ameliorates GIS by reducing crypt cell death. Thus, we propose blocking TLR3 activation as a novel approach to treat GIS. PMID:24637670

  5. Radiation-induced complications in prostate cancer patients treated with radiotherapy

    SciTech Connect

    Azuddin, A. Yusof; Rahman, I. Abdul; Mohamed, F.; Siah, N. J.; Saadc, M.; Ismail, F.

    2014-09-03

    The purpose of the study is to determine the relationship between radiation-induced complications with dosimetric and radiobiological parameters for prostate cancer patients that underwent the conformal radiotherapy treatment. 17 prostate cancer patients that have been treated with conformal radiotherapy were retrospectively analysed. The dosimetric data was retrieved in the form of dose-volume histogram (DVH) from Radiotherapy Treatment Planning System. The DVH was utilised to derived Normal Tissue Complication Probability (NTCP) in radiobiological data. Follow-up data from medical records were used to grade the occurrence of acute gastrointestinal (GI) and genitourinary (GU) complications using Radiation Therapy Oncology Group (RTOG) scoring system. The chi-square test was used to determine the relationship between radiation-induced complication with dosimetric and radiobiological parameters. 8 (47%) and 7 (41%) patients were having acute GI and GU complications respectively. The acute GI complication can be associated with V60{sub rectum}, rectal mean dose and NTCP{sub rectum} with p-value of 0.016, 0.038 and 0.049 respectively. There are no significant relationships of acute GU complication with dosimetric and radiobiological variables. Further study can be done by increase the sample size and follow up duration for deeper understanding of the factors that effecting the GU and GI complication in prostate cancer radiotherapy.

  6. Radiation-induced metabolomic changes in sterile male Μοnochamus alternatus (Coleoptera: Cerambycidae).

    PubMed

    Qu, L J; Wang, L J; Zhang, Y A; Wang, Q H; Wang, Y Z; Zhao, T H; Cai, W Z

    2014-01-01

    Radiation-induced sterile insect technique is a biologically based, environment-friendly method for the suppression or eradication of a number of insect pests. Although the basic mechanisms underlying the technology have been well studied, little is known about the cell responses in organisms. Characterization of the metabolic shift associated with radiation exposure in sterile insects would be helpful for understanding the detailed mechanism underlying this technique and promote its practical application. In this article, a metabolomic study was performed to characterize the global metabolic changes induced by radiation using untreated and 40 Gy (60)Coγ-irradiated testes of Japanese pine sawyer, Monochamus alternatus Hope. Differential metabolites were detected and tentatively identified. Many key metabolites in glycolysis and the tricarboxylic acid cycle, as well as most fatty and amino acids, were elevated in irradiated male M. alternatus, presumably resulting from depression of glycolysis and the tricarboxylic acid cycle, each of which are important pathways for energy generation Adenosine Triphosphate (ATP) in insect spermatozoa. The findings in this article will contribute to our knowledge of the characteristic metabolic changes associated with irradiation sterility and understand the molecular mechanisms underlying radiation-induced sterile insect technique.

  7. Mucoadhesive propolis gel for prevention of radiation-induced oral mucositis.

    PubMed

    Noronha, Vladimir R A S; Araujo, Gustavo S; Gomes, Rafael T; Iwanaga, Samara H; Barbosa, Maralice C; Abdo, Evandro N; Ferreira e Ferreira, Efigenia; Viana Campos, Ana C; Souza, Alexandre A; Abreu, Sheila R L; Santos, Vagner R

    2014-01-01

    The objective of this phase II study was to determine the effectiveness of a mucoadhesive propolis gel in the prevention of radiation-induced oral mucositis. Twenty-four patients who were selected to undergo radiation therapy for oral cancer were included in this open-label trial. They were advised to use a mucoadhesive gel containing propolis 5,0% w/v three times a day starting one day before the course of radiation therapy and concluding after 2 weeks of radiation therapy. A weekly follow-up for evaluation of food intake, pain and grading of mucositis was performed. In order to confirm the absence of Candida-related mucositis in patients who developed mucositis, it was performed exfoliative cytology of buccal mucosa, palate and tongue and the material for Candifast(®) Candida species identification. At the end of the study was made the compliance of patients, quality, appreciation and acceptance of product evaluation. Twenty patients did not develop mucositis, two patients developed grade 1 mucositis and two patients developed grade 2 mucositis. None of the patients discontinued food intake and no pain was observed during the study. Candidosis was not detected in any patient. Mucoadhesive propolis gel could be considered as a potential topical medication for preventing radiation-induced oral mucositis. However, comparative phase III study with larger number of patients should be done for confirmation of the efficacy of the product.

  8. Harnessing a radiation inducible promoter of Deinococcus radiodurans for enhanced precipitation of uranium.

    PubMed

    Misra, Chitra Seetharam; Mukhopadhyaya, Rita; Apte, Shree Kumar

    2014-11-10

    Bioremediation is an attractive option for the treatment of radioactive waste. We provide a proof of principle for augmentation of uranium bioprecipitation using the radiation inducible promoter, Pssb from Deinococcus radiodurans. Recombinant cells of D. radiodurans carrying acid phosphatase gene, phoN under the regulation of Pssb when exposed to 7 kGy gamma radiation at two different dose rates of 56.8 Gy/min and 4 Gy/min, showed 8-9 fold increase in acid phosphatase activity. Highest whole cell PhoN activity was obtained after 2h in post irradiation recovery following 8 kGy of high dose rate radiation. Such cells showed faster removal of high concentrations of uranium than recombinant cells expressing PhoN under a radiation non-inducible deinococcal promoter, PgroESL and could precipitate uranium even after continuous exposure to 0.6 Gy/min gamma radiation for 10 days. Radiation induced recombinant D. radiodurans cells when lyophilized retained high levels of PhoN activity and precipitated uranium efficiently. These results highlight the importance of using a suitable promoter for removal of radionuclides from solution.

  9. Radiation-induced damage to cellular DNA: Chemical nature and mechanisms of lesion formation

    NASA Astrophysics Data System (ADS)

    Cadet, Jean; Wagner, J. Richard

    2016-11-01

    This mini-review focuses on the recent identification of several novel radiation-induced single and tandem modifications in cellular DNA. For this purpose accurate high-performance electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) was applied allowing their quantitative measurement and unambiguous characterization. Exposure of human cells to gamma rays led to the formation of several modified bases arising from the rearrangement of the pyrimidine ring of thymine, cytosine and 5-methylcytosine subsequent to initial addition of an hydroxyl radical (•OH) to the 5,6-ethylenic bond. In addition, 5-hydroxymethylcytosine, an novel epigenetic mark, and 5-formylcytosine, were found to be generated consecutively to •OH-mediated hydrogen abstraction from the methyl group of 5-methylcytosine. Relevant mechanistic information on one-oxidation reactions of cellular DNA was also gained from the detection of 5-hydroxycytosine and guanine-thymine intra-strand adducts whose formation is rationalized by the generation of related base radical cation. Attempts to search for the radiation-induced formation of purine 5‧,8-cyclo-2‧-deoxyribonucleosides were unsuccessful with the exception of trace amounts of (5‧S)-5‧,8-cyclo-2‧-deoxyadenosine.

  10. Protective effects of alpha lipoic acid on radiation-induced salivary gland injury in rats

    PubMed Central

    Kim, Jin Hyun; Kim, Kyung Mi; Jung, Myeong Hee; Jung, Jung Hwa; Kang, Ki Mun; Jeong, Bae Kwon; Kim, Jin Pyeong; Park, Jung Je; Woo, Seung Hoon

    2016-01-01

    Purpose Radiation therapy is a treatment for patients with head and neck (HN) cancer. However, radiation exposure to the HN often induces salivary gland (SG) dysfunction. We investigated the effect of α-lipoic acid (ALA) on radiation-induced SG injury in rats. Results ALA preserved acinoductal integrity and acinar cell secretary function following irradiation. These results are related to the mechanisms by which ALA inhibits oxidative stress by inhibiting gp91 mRNA and 8-OHdG expression and apoptosis of acinar cells and ductal cells by inactivating MAPKs in the early period and expression of inflammation-related factors including NF-κB, IκB-α, and TGF-β1 and fibrosis in late irradiated SG. ALA effects began in the acute phase and persisted for at least 56 days after irradiation. Materials and Methods Rats were assigned to followings: control, ALA only (100 mg/kg, i.p.), irradiated, and ALA administered 24 h and 30 min prior to irradiation. The neck area including the SG was evenly irradiated with 2 Gy per minute (total dose, 18 Gy) using a photon 6-MV linear accelerator. Rats were killed at 4, 7, 28, and 56 days after radiation. Conclusions Our results show that ALA could be used to ameliorate radiation-induced SG injury in patients with HN cancer. PMID:27072584

  11. Preclinical evaluation of erythropoietin administration in a model of radiation-induced kidney dysfunction

    SciTech Connect

    Andratschke, Nicolaus; Schnaitera, Andrea; Weber, Wolfgang A.; Caia, Lu; Schill, Sabine; Wiedenmann, Nicole; Schwaiger, Markus; Molls, Michael; Nieder, Carsten . E-mail: cnied@hotmail.com

    2006-04-01

    Purpose: To test whether the clinically available growth factor erythropoietin (EPO) influences radiation-induced normal-tissue damage in a model of kidney dysfunction. Methods: Animal experiments were conducted to test the role of EPO administration in a C3H mouse model of unilateral kidney irradiation with 6, 8, and 10 Gy and to assess the effects of 2 different dose levels of EPO. The kidney function was assessed before radiotherapy, as well as 19, 25, 31, and 37 weeks thereafter by means of {sup 99m}Tc-dimercaptosuccinat scans (static scintigraphy). Results: Concomitant EPO administration significantly increased the degree of radiation-induced kidney dysfunction. A dose of 2,000 IU/kg body weight per injection tended to cause more damage than the lower dose of 500 IU/kg. Conclusion: Administration of growth factors concomitant to radiotherapy might modify the development of kidney dysfunction. Although insulin-like growth factor-1 has previously been shown to protect the kidney, such an effect could not be demonstrated for EPO. The latter agent even increased the development of nephropathy.

  12. Consequences of ionizing radiation-induced damage in human neural stem cells.

    PubMed

    Acharya, Munjal M; Lan, Mary L; Kan, Vickie H; Patel, Neal H; Giedzinski, Erich; Tseng, Bertrand P; Limoli, Charles L

    2010-12-15

    Cranial irradiation remains a frontline treatment for brain cancer, but also leads to normal tissue damage. Although low-dose irradiation (≤10 Gy) causes minimal histopathologic change, it can elicit variable degrees of cognitive dysfunction that are associated with the depletion of neural stem cells. To decipher the mechanisms underlying radiation-induced stem cell dysfunction, human neural stem cells (hNSCs) subjected to clinically relevant irradiation (0-5 Gy) were analyzed for survival parameters, cell-cycle alterations, DNA damage and repair, and oxidative stress. hNSCs showed a marked sensitivity to low-dose irradiation that was in part due to elevated apoptosis and the inhibition of cell-cycle progression that manifested as a G2/M checkpoint delay. Efficient removal of DNA double-strand breaks was indicated by the disappearance of γ-H2AX nuclear foci. A dose-responsive and persistent increase in oxidative and nitrosative stress was found in irradiated hNSCs, possibly the result of a higher metabolic activity in the fraction of surviving cells. These data highlight the marked sensitivity of hNSCs to low-dose irradiation and suggest that long-lasting perturbations in the CNS microenvironment due to radiation-induced oxidative stress can compromise the functionality of neural stem cells.

  13. The Development of Countermeasures for Space Radiation Induced Adverse Health Effects

    NASA Astrophysics Data System (ADS)

    Kennedy, Ann

    The Development of Countermeasures for Space Radiation Induced Adverse Health Effects Ann R. Kennedy Department of Radiation Oncology, University of Pennsylvania School of Medicine, 195 John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA, United States 19104-6072 The development of countermeasures for radiation induced adverse health effects is a lengthy process, particularly when the countermeasure/drug has not yet been evaluated in human trials. One example of a drug developed from the bench to the clinic is the soybean-derived Bowman-Birk inhibitor (BBI), which has been developed as a countermeasure for radiation induced cancer. It was originally identified as a compound/drug that could prevent the radiation induced carcinogenic process in an in vitro assay system in 1975. The first observation that BBI could inhibit carcinogenesis in animals was in 1985. BBI received Investigational New Drug (IND) Status with the U.S. Food and Drug Administration (FDA) in 1992 (after several years of negotiation with the FDA about the potential IND status of the drug), and human trials began at that time. Phase I, II and III human trials utilizing BBI have been performed under several INDs with the FDA, and an ongoing Phase III trial will be ending in the very near future. Thus, the drug has been in development for 35 years at this point, and it is still not a prescription drug on the market which is available for human use. A somewhat less time-consuming process is to evaluate compounds that are on the GRAS (Generally Recognized as Safe) list. These compounds would include some over-the-counter medications, such as antioxidant vitamins utilized in human trials at the levels for which Recommended Dietary Allowances (RDAs) have been established. To determine whether GRAS substances are able to have beneficial effects on radiation induced adverse health effects, it is still likely to be a lengthy process involving many years to potentially decades of human trial work. The

  14. Mensenchymal stem cells can delay radiation-induced crypt death: impact on intestinal CD44(+) fragments.

    PubMed

    Chang, Peng-Yu; Jin, Xing; Jiang, Yi-Yao; Wang, Li-Xian; Liu, Yong-Jun; Wang, Jin

    2016-05-01

    Intestinal stem cells are primitive cells found within the intestinal epithelium that play a central role in maintaining epithelial homeostasis through self-renewal and commitment into functional epithelial cells. Several markers are available to identify intestinal stem cells, such as Lgr5, CD24 and EphB2, which can be used to sort intestinal stem cells from mammalian gut. Here, we identify and isolate intestinal stem cells from C57BL/6 mice by using a cell surface antigen, CD44. In vitro, some CD44(+) crypt cells are capable of forming "villus-crypt"-like structures (organoids). A subset strongly positive for CD44 expresses high levels of intestinal stem-cell-related genes, including Lgr5, Bmi1, Hopx, Lrig1, Ascl2, Smoc2 and Rnf43. Cells from this subset are more capable of developing into organoids in vitro, compared with the subset weakly positive for CD44. However, the organoids are sensitive to ionizing irradiation. We investigate the specific roles of mesenchymal stem cells in protecting organoids against radiation-induced crypt death. When co-cultured with mesenchymal stem cells, the crypt domains of irradiated organoids possess more proliferative cells and fewer apoptotic cells than those not co-cultured with mesenchymal stem cells. Cd44v6 continues to be expressed in the crypt domains of irradiated organoids co-cultured with mesenchymal stem cells. Our results indicate specific roles of mesenchymal stem cells in delaying radiation-induced crypt death in vitro.

  15. The role of alveolar epithelium in radiation-induced lung injury.

    PubMed

    Almeida, Celine; Nagarajan, Devipriya; Tian, Jian; Leal, Sofia Walder; Wheeler, Kenneth; Munley, Michael; Blackstock, William; Zhao, Weiling

    2013-01-01

    Pneumonitis and fibrosis are major lung complications of irradiating thoracic malignancies. In the current study, we determined the effect of thoracic irradiation on the lungs of FVB/N mice. Survival data showed a dose-dependent increase in morbidity following thoracic irradiation with single (11-13 Gy) and fractionated doses (24-36 Gy) of (137)Cs γ-rays. Histological examination showed a thickening of vessel walls, accumulation of inflammatory cells, collagen deposition, and regional fibrosis in the lungs 14 weeks after a single 12 Gy dose and a fractionated 30 Gy dose; this damage was also seen 5 months after a fractionated 24 Gy dose. After both single and fractionated doses, i] aquaporin-5 was markedly decreased, ii] E-cadherin was reduced and iii] prosurfactant Protein C (pro-SP-c), the number of pro-SP-c(+) cells and vimentin expression were increased in the lungs. Immunofluorescence analysis revealed co-localization of pro-SP-c and α-smooth muscle actin in the alveoli after a single dose of 12 Gy. These data suggest that, i] the FVB/N mouse strain is sensitive to thoracic radiation ii] aquaporin-5, E-cadherin, and pro-SP-c may serve as sensitive indicators of radiation-induced lung injury; and iii] the epithelial-to-mesenchymal transition may play an important role in the development of radiation-induced lung fibrosis.

  16. Radiation-induced attenuation self-compensating effect in super-fluorescent fiber source

    NASA Astrophysics Data System (ADS)

    Yang, Yuan-Hong; Suo, Xin-Xin; Yang, Wei

    2014-09-01

    The compact super-fluorescent fiber source (SFS) output spectra variations at different pump currents and under different dose of gamma-ray radiation were measured and compared respectively. The radiation-induced attenuation (RIA) self-compensating effect in SFS based on photo-bleaching was found and the general mathematic model of SFS output spectra variations was made. The radiation-induced background attenuation (RIBA) at the pump wavelength was identified to be the main cause of the total output power and spectra variations and the variations can then be compensated by active control of the pump power to enhance the self-compensating effect. With closed-loop feedback control of pump current, double-pass backward (DPB) configuration and spectrum re-shaping technology, an SFS prototype was made and tested. The mean-wavelength stability of about 87.4 ppm and output power instability of less than 5% were achieved under up to 200 krad (Si) gamma-ray irradiation.

  17. Effects of inhibitors of radiation-induced potentially lethal damage repair on chemotherapy in murine tumors

    SciTech Connect

    Nakatsugawa, S.; Sugahara, T.

    1982-09-01

    Enhancement of various antitumor drugs effects by inhibitors of radiation-induced potentially lethal damage (PLD) repair was studied in three murine tumors (EMT-6, RIF-1 and SQ-1). In EMT-6 tumors, PLD repair inhibitors, 3'-deoxyguanosine (3'dG) and 7904 (a derivative of 3'-deoxyadenosine) showed a marked enhancement of tumor growth inhibition by anticancerous drugs (FT-207 (a derivative of 5-FU), bleomycin, Ara-C, ACNU). However, the effects of mitomycin-C and vincristine were not potentiated by the inhibitors. In SQ-1 carcinomas, another repair inhibitor, ara-A (1-..beta..-D-arabinofuranosyladenine) (32 mg/kg) potentiated the effect of ACNU. In RIF-1 sarcomas, in which a low PLD repair function has been reported after ionizing radiation exposure, the potentiation was not so marked as in EMT-6 or SQ-1 tumors. Thus, as a possibility, the potentiation by inhibitors of radiation-induced PLD repair might be a result of the inhibition of chemical-induced PLD repair. The study of this field may contribute to the improvement of cancer treatment not only by radiotherapy but also by chemotherapy.

  18. [Involvement of ATP in radiation-induced bystander effect as a signaling molecule].

    PubMed

    Kojima, Shuji

    2014-01-01

    We previously reported that low doses (0.25-0.5 Gy) of γ-rays induce intracellular antioxidant, radioresistant, DNA damage repair, and so on. Meanwhile, we have recently reported that ATP is released from the cells exposed to low-dose γ-rays. Here, it was investigated whether or not γ-radiation-induced release of extracellular ATP contributes to various radiation effects, in paricular, focusing on the inductions of intracellular antioxidant and DNA damage repair. Irradiation with γ-rays or exogenously added ATP increased expression of intracellular antioxidants such as thioredoxin and the increases were blocked by pretreatment with an ecto-nucleotidase in both cases. Moreover, release of ATP and autocrine/paracrine positive feedback through P2Y receptors serve to amplify the cellular repair response to radiation-induced DNA damage. To sum up, it would be suggested that ATP signaling is important for the effective induction of radiation stress response, such as protection of the body from the radiation and DNA damage repair. In addition, the possibility that this signaling is involved in the radiation resistance of cancer cells and beneficial effect on the organism of low-dose radiation and radiation adaptive response, would be further suggested.

  19. A non-human primate model of radiation-induced cachexia

    PubMed Central

    Cui, Wanchang; Bennett, Alexander W.; Zhang, Pei; Barrow, Kory R.; Kearney, Sean R.; Hankey, Kim G.; Taylor-Howell, Cheryl; Gibbs, Allison M.; Smith, Cassandra P.; MacVittie, Thomas J.

    2016-01-01

    Cachexia, or muscle wasting, is a serious health threat to victims of radiological accidents or patients receiving radiotherapy. Here, we propose a non-human primate (NHP) radiation-induced cachexia model based on clinical and molecular pathology findings. NHP exposed to potentially lethal partial-body irradiation developed symptoms of cachexia such as body weight loss in a time- and dose-dependent manner. Severe body weight loss as high as 20–25% was observed which was refractory to nutritional intervention. Radiographic imaging indicated that cachectic NHP lost as much as 50% of skeletal muscle. Histological analysis of muscle tissues showed abnormalities such as presence of central nuclei, inflammation, fatty replacement of skeletal muscle, and muscle fiber degeneration. Biochemical parameters such as hemoglobin and albumin levels decreased after radiation exposure. Levels of FBXO32 (Atrogin-1), ActRIIB and myostatin were significantly changed in the irradiated cachectic NHP compared to the non-irradiated NHP. Our data suggest NHP that have been exposed to high dose radiation manifest cachexia-like symptoms in a time- and dose-dependent manner. This model provides a unique opportunity to study the mechanism of radiation-induced cachexia and will aid in efficacy studies of mitigators of this disease. PMID:27029502

  20. A non-human primate model of radiation-induced cachexia.

    PubMed

    Cui, Wanchang; Bennett, Alexander W; Zhang, Pei; Barrow, Kory R; Kearney, Sean R; Hankey, Kim G; Taylor-Howell, Cheryl; Gibbs, Allison M; Smith, Cassandra P; MacVittie, Thomas J

    2016-03-31

    Cachexia, or muscle wasting, is a serious health threat to victims of radiological accidents or patients receiving radiotherapy. Here, we propose a non-human primate (NHP) radiation-induced cachexia model based on clinical and molecular pathology findings. NHP exposed to potentially lethal partial-body irradiation developed symptoms of cachexia such as body weight loss in a time- and dose-dependent manner. Severe body weight loss as high as 20-25% was observed which was refractory to nutritional intervention. Radiographic imaging indicated that cachectic NHP lost as much as 50% of skeletal muscle. Histological analysis of muscle tissues showed abnormalities such as presence of central nuclei, inflammation, fatty replacement of skeletal muscle, and muscle fiber degeneration. Biochemical parameters such as hemoglobin and albumin levels decreased after radiation exposure. Levels of FBXO32 (Atrogin-1), ActRIIB and myostatin were significantly changed in the irradiated cachectic NHP compared to the non-irradiated NHP. Our data suggest NHP that have been exposed to high dose radiation manifest cachexia-like symptoms in a time- and dose-dependent manner. This model provides a unique opportunity to study the mechanism of radiation-induced cachexia and will aid in efficacy studies of mitigators of this disease.

  1. Radiation-induced cardiovascular diseases: Is the epidemiologic evidence compatible with the radiobiologic data?

    SciTech Connect

    Schultz-Hector, Susanne . E-mail: susanne.schultz-hector@helmholtz.de; Trott, Klaus-Ruediger Prof.

    2007-01-01

    The Life Span Study of Japanese atomic bomb survivors demonstrates that radiation exposure significantly increased the risk of developing ischemic heart disease, in particular myocardial infarction. Similarly, epidemiologic investigations in very large populations of patients who had received postoperative radiotherapy for breast cancer or for peptic ulcer demonstrate that radiation exposure of the heart with an average equivalent single dose of approximately 2 Gy significantly increased the risk of developing ischemic heart disease more than 10 years after irradiation. These epidemiologic findings are compatible with radiobiologic data on the pathogenesis of radiation-induced heart disease in experimental animals. The critical target structure appears to be the endothelial lining of blood vessels, in particular arteries, leading to early functional alterations such as pro-inflammatory responses and other changes, which are slowly progressive. Research should concentrate on the interaction of these radiation-induced endothelial changes with the early stages of age-related atherosclerosis to develop criteria for optimizing treatment plans in radiotherapy and also potential interventional strategies.

  2. Radiation-induced alarm and failure of an implanted programmable intrathecal pump.

    PubMed

    Wu, Hong; Wang, Dian

    2007-01-01

    Numerous potential complications are associated with the use of programmable intrathecal (IT) drug delivery systems. Radiation is often assumed to cause dysfunctions of the programmable IT device. However, radiation-induced failure of this device and limits of dose exposure have not clinically documented. Here we reported an alarm and failure of an implanted programmable IT pump in a turn-off status exposed directly to radiation used for treatment of a retroperitoneal sarcoma. The radiation-induced alarm was likely secondary to the electronic circuit damage and/or battery depletion. Estimated cumulative doses to the pump were in the range of 28.5 to 36 Gy when the alarm occurred after 20 daily treatments. The IT pump itself exposed to this high-dose radiation did not pose any risk to the patient or the environment. This is the first case description about the pump malfunction secondary to clinical radiotherapy, which is very useful to physicians who manage the pain and radiotherapy for cancer patients.

  3. Radiation induces the generation of cancer stem cells: A novel mechanism for cancer radioresistance

    PubMed Central

    Li, Fengsheng; Zhou, Kunming; Gao, Ling; Zhang, Bin; Li, Wei; Yan, Weijuan; Song, Xiujun; Yu, Huijie; Wang, Sinian; Yu, Nan; Jiang, Qisheng

    2016-01-01

    Radioresistance remains a major obstacle for the radiotherapy treatment of cancer. Previous studies have demonstrated that the radioresistance of cancer is due to the existence of intrinsic cancer stem cells (CSCs), which represent a small, but radioresistant cell subpopulation that exist in heterogeneous tumors. By contrast, non-stem cancer cells are considered to be radiosensitive and thus, easy to kill. However, recent studies have revealed that under conditions of radiation-induced stress, theoretically radiosensitive non-stem cancer cells may undergo dedifferentiation subsequently obtaining the phenotypes and functions of CSCs, including high resistance to radiotherapy, which indicates that radiation may directly result in the generation of novel CSCs from non-stem cancer cells. These findings suggest that in addition to intrinsic CSCs, non-stem cancer cells may also contribute to the relapse and metastasis of cancer following transformation into CSCs. This review aims to investigate the radiation-induced generation of CSCs, its association with epithelial-mesenchymal transition and its significance with regard to the radioresistance of cancer. PMID:27899964

  4. Proximity within interphase chromosome contributes to the breakpoint distribution in radiation-induced intrachromosomal exchanges

    NASA Astrophysics Data System (ADS)

    Zhang, Ye; Uhlemeyer, Jimmy; Hada, Megumi; Asaithamby, A.; Chen, David J.; Wu, Honglu

    2014-07-01

    Previously, we reported that breaks involved in chromosome aberrations were clustered in several regions of chromosome 3 in human mammary epithelial cells after exposures to either low- or high-LET radiation. In particular, breaks in certain regions of the chromosome tended to rejoin with each other to form an intrachromosome exchange event. This study tests the hypothesis that proximity within a single chromosome in interphase cell nuclei contributes to the distribution of radiation-induced chromosome breaks. Chromosome 3 in G1 human mammary epithelial cells was hybridized with the multicolor banding in situ hybridization (mBAND) probes that distinguish the chromosome in six differently colored regions, and the location of these regions was measured with a laser confocal microscope. Results of the study indicated that, on a multi-mega base pair scale of the DNA, the arrangement of chromatin was non-random. Both telomere regions tended to be located towards the exterior of the chromosome domain, whereas the centromere region towards the interior. In addition, the interior of the chromosome domain was preferentially occupied by the p-arm of the chromatin, which is consistent with our previous finding of intrachromosome exchanges involving breaks on the p-arm and in the centromere region of chromosome 3. Other factors, such as the fragile sites in the 3p21 band and gene regulation, may also contribute to the breakpoint distribution in radiation-induced chromosome aberrations.

  5. Live cell microscopy analysis of radiation-induced DNA double-strand break motion

    PubMed Central

    Jakob, B.; Splinter, J.; Durante, M.; Taucher-Scholz, G.

    2009-01-01

    We studied the spatiotemporal organization of DNA damage processing by live cell microscopy analysis in human cells. In unirradiated U2OS osteosarcoma and HeLa cancer cells, a fast confined and Brownian-like motion of DNA repair protein foci was observed, which was not altered by radiation. By analyzing the motional activity of GFP-53BP1 foci in live cells up to 12-h after irradiation, we detected an additional slower mobility of damaged chromatin sites showing a mean square displacement of ≈0.6 μm2/h after exposure to densely- or sparsely-ionizing radiation, most likely driven by normal diffusion of chromatin. Only occasionally, larger translational motion connected to morphological changes of the whole nucleus could be observed. In addition, there was no general tendency to form repair clusters in the irradiated cells. We conclude that long-range displacements of damaged chromatin domains do not generally occur during DNA double-strand break repair after introduction of multiple damaged sites by charged particles. The occasional and in part transient appearance of cluster formation of radiation-induced foci may represent a higher mobility of chromatin along the ion trajectory. These observations support the hypothesis that spatial proximity of DNA breaks is required for the formation of radiation-induced chromosomal exchanges. PMID:19221031

  6. The nucleus is the target for radiation-induced chromosomal instability

    NASA Technical Reports Server (NTRS)

    Kaplan, M. I.; Morgan, W. F.

    1998-01-01

    We have previously described chromosomal instability in cells of a human-hamster hybrid cell line after exposure to X rays. Chromosomal instability in these cells is characterized by the appearance of novel chromosomal rearrangements multiple generations after exposure to ionizing radiation. To identify the cellular target(s) for radiation-induced chromosomal instability, cells were treated with 125I-labeled compounds and frozen. Radioactive decays from 125I cause damage to the cell primarily at the site of their decay, and freezing the cells allows damage to accumulate in the absence of other cellular processes. We found that the decay of 125I-iododeoxyuridine, which is incorporated into the DNA, caused chromosomal instability. While cell killing and first-division chromosomal rearrangements increased with increasing numbers of 125I decays, the frequency of chromosomal instability was independent of dose. Chromosomal instability could also be induced from incorporation of 125I-iododeoxyuridine without freezing the cells for accumulation of decays. This indicates that DNA double-strand breaks in frozen cells resulting from 125I decays failed to lead to instability. Incorporation of an 125I-labeled protein (125I-succinyl-concanavalin A), which was internalized into the cell and/or bound to the plasma membrane, neither caused chromosomal instability nor potentiated chromosomal instability induced by 125I-iododeoxyuridine. These results show that the target for radiation-induced chromosomal instability in these cells is the nucleus.

  7. Rejoining and misrejoining of radiation-induced chromatin breaks. III. Hypertonic treatment

    NASA Technical Reports Server (NTRS)

    Durante, M.; George, K.; Wu, H. L.; Yang, T. C.

    1998-01-01

    It has been shown that treatment in anisotonic medium modifies rejoining of radiation-induced breaks in interphase chromosomes. In previous work, we have demonstrated that formation of exchanges in human lymphocytes has a slow component (half-time of 1-2 h), but a fraction of exchanges are also observed in samples assayed soon after exposure. In this paper we studied the effect of hypertonic treatment on rejoining and misrejoining of radiation-induced breaks using fluorescence in situ hybridization of prematurely condensed chromosomes in human lymphocytes. Isolated lymphocytes were irradiated with 7 Gy gamma rays, fused to mitotic hamster cells and incubated in hypertonic solution (0.5 M NaCl) for the period normally allowed for interphase chromosome condensation to occur. The data from hypertonic treatment experiments indicate the presence of a class of interphase chromosome breaks that rejoin and misrejoin very quickly (half-time of 5-6 min). The fast misrejoining of these lesions is considered to be responsible for the initial level of exchanges which we reported previously. No significant effect of hypertonic treatment on the yield of chromosome aberrations scored at the first postirradiation mitosis was detected.

  8. Induction of Excess Centrosomes in Neural Progenitor Cells during the Development of Radiation-Induced Microcephaly

    PubMed Central

    Shimada, Mikio; Matsuzaki, Fumio; Kato, Akihiro; Kobayashi, Junya; Matsumoto, Tomohiro; Komatsu, Kenshi

    2016-01-01

    The embryonic brain is one of the tissues most vulnerable to ionizing radiation. In this study, we showed that ionizing radiation induces apoptosis in the neural progenitors of the mouse cerebral cortex, and that the surviving progenitor cells subsequently develop a considerable amount of supernumerary centrosomes. When mouse embryos at Day 13.5 were exposed to γ-rays, brains sizes were reduced markedly in a dose-dependent manner, and these size reductions persisted until birth. Immunostaining with caspase-3 antibodies showed that apoptosis occurred in 35% and 40% of neural progenitor cells at 4 h after exposure to 1 and 2 Gy, respectively, and this was accompanied by a disruption of the apical layer in which mitotic spindles were positioned in unirradiated mice. At 24 h after 1 Gy irradiation, the apoptotic cells were completely eliminated and proliferation was restored to a level similar to that of unirradiated cells, but numerous spindles were localized outside the apical layer. Similarly, abnormal cytokinesis, which included multipolar division and centrosome clustering, was observed in 19% and 24% of the surviving neural progenitor cells at 48 h after irradiation with 1 and 2 Gy, respectively. Because these cytokinesis aberrations derived from excess centrosomes result in growth delay and mitotic catastrophe-mediated cell elimination, our findings suggest that, in addition to apoptosis at an early stage of radiation exposure, radiation-induced centrosome overduplication could contribute to the depletion of neural progenitors and thereby lead to microcephaly. PMID:27367050

  9. A biological approach to the interspecies prediction of radiation-induced mortality risk

    SciTech Connect

    Carnes, B.A.; Grahn, D.; Olshansky, S.J.

    1997-08-01

    Evolutionary explanations for why sexually reproducing organisms grow old suggest that the forces of natural selection affect the ages when diseases occur that are subject to a genetic influence (referred to here as intrinsic diseases). When extended to the population level for a species, this logic leads to the general prediction that age-specific death rates from intrinsic causes should begin to rise as the force of selection wanes once the characteristic age of sexual maturity is attained. Results consistent with these predictions have been found for laboratory mice, beagles, and humans where, after adjusting for differences in life span, it was demonstrated that these species share a common age pattern of mortality for intrinsic causes of death. In quantitative models used to predict radiation-induced mortality, risks are often expressed as multiples of those observed in a control population. A control population, however, is an aging population. As such, mortality risks related to exposure must be interpreted relative to the age-specific risk of death associated with aging. Given the previous success in making interspecies predictions of age-related mortality, the purpose of this study was to determine whether radiation-induced mortality observed in one species could also be predicted quantitatively from a model used to describe the mortality consequences of exposure to radiation in a different species. Mortality data for B6CF{sub 1} mice and beagles exposed to {sup 60}Co {gamma}-rays for the duration of life were used for analysis.

  10. Protective effect of mild endoplasmic reticulum stress on radiation-induced bystander effects in hepatocyte cells

    PubMed Central

    Xie, Yuexia; Ye, Shuang; Zhang, Jianghong; He, Mingyuan; Dong, Chen; Tu, Wenzhi; Liu, Peifeng; Shao, Chunlin

    2016-01-01

    Radiation-induced bystander effect (RIBE) has important implications for secondary cancer risk assessment during cancer radiotherapy, but the defense and self-protective mechanisms of bystander normal cells are still largely unclear. The present study found that micronuclei (MN) formation could be induced in the non-irradiated HL-7702 hepatocyte cells after being treated with the conditioned medium from irradiated hepatoma HepG2 cells under either normoxia or hypoxia, where the ratio of the yield of bystander MN induction to the yield of radiation-induced MN formation under hypoxia was much higher than that of normoxia. Nonetheless, thapsigargin induced endoplasmic reticulum (ER) stress and dramatically suppressed this bystander response manifested as the decrease of MN and apoptosis inductions. Meanwhile, the interference of BiP gene, a major ER chaperone, amplified the detrimental RIBE. More precisely, thapsigargin provoked ER sensor of PERK to initiate an instantaneous and moderate ER stress thus defensed the hazard form RIBE, while BiP depletion lead to persistently destroyed homeostasis of ER and exacerbated cell injury. These findings provide new insights that the mild ER stress through BiP-PERK-p-eIF2α signaling pathway has a profound role in protecting cellular damage from RIBE and hence may decrease the potential secondary cancer risk after cancer radiotherapy. PMID:27958308

  11. PHD inhibition mitigates and protects against radiation-induced gastrointestinal toxicity via HIF2.

    PubMed

    Taniguchi, Cullen M; Miao, Yu Rebecca; Diep, Anh N; Wu, Colleen; Rankin, Erinn B; Atwood, Todd F; Xing, Lei; Giaccia, Amato J

    2014-05-14

    Radiation-induced gastrointestinal (GI) toxicity can be a major source of morbidity and mortality after radiation exposure. There is an unmet need for effective preventative or mitigative treatments against the potentially fatal diarrhea and water loss induced by radiation damage to the GI tract. We report that prolyl hydroxylase inhibition by genetic knockout or pharmacologic inhibition of all PHD (prolyl hydroxylase domain) isoforms by the small-molecule dimethyloxallyl glycine (DMOG) increases hypoxia-inducible factor (HIF) expression, improves epithelial integrity, reduces apoptosis, and increases intestinal angiogenesis, all of which are essential for radioprotection. HIF2, but not HIF1, is both necessary and sufficient to prevent radiation-induced GI toxicity and death. Increased vascular endothelial growth factor (VEGF) expression contributes to the protective effects of HIF2, because inhibition of VEGF function reversed the radioprotection and radiomitigation afforded by DMOG. Additionally, mortality from abdominal or total body irradiation was reduced even when DMOG was given 24 hours after exposure. Thus, prolyl hydroxylase inhibition represents a treatment strategy to protect against and mitigate GI toxicity from both therapeutic radiation and potentially lethal radiation exposures.

  12. Mitigating the risk of radiation-induced cancers: limitations and paradigms in drug development.

    PubMed

    Yoo, Stephen S; Jorgensen, Timothy J; Kennedy, Ann R; Boice, John D; Shapiro, Alla; Hu, Tom C-C; Moyer, Brian R; Grace, Marcy B; Kelloff, Gary J; Fenech, Michael; Prasanna, Pataje G S; Coleman, C Norman

    2014-06-01

    The United States radiation medical countermeasures (MCM) programme for radiological and nuclear incidents has been focusing on developing mitigators for the acute radiation syndrome (ARS) and delayed effects of acute radiation exposure (DEARE), and biodosimetry technologies to provide radiation dose assessments for guiding treatment. Because a nuclear accident or terrorist incident could potentially expose a large number of people to low to moderate doses of ionising radiation, and thus increase their excess lifetime cancer risk, there is an interest in developing mitigators for this purpose. This article discusses the current status, issues, and challenges regarding development of mitigators against radiation-induced cancers. The challenges of developing mitigators for ARS include: the long latency between exposure and cancer manifestation, limitations of animal models, potential side effects of the mitigator itself, potential need for long-term use, the complexity of human trials to demonstrate effectiveness, and statistical power constraints for measuring health risks (and reduction of health risks after mitigation) following relatively low radiation doses (<0.75 Gy). Nevertheless, progress in the understanding of the molecular mechanisms resulting in radiation injury, along with parallel progress in dose assessment technologies, make this an opportune, if not critical, time to invest in research strategies that result in the development of agents to lower the risk of radiation-induced cancers for populations that survive a significant radiation exposure incident.

  13. Protective effect of esculentoside A on radiation-induced dermatitis and fibrosis

    SciTech Connect

    Xiao Zhenyu; Su Ying; Yang Shanmin; Yin Liangjie; Wang Wei; Yi Yanghua; Fenton, Bruce M.; Zhang Lurong; Okunieff, Paul . E-mail: paul_okunieff@urmc.rochester.edu

    2006-07-01

    Purpose: To investigate the effect of esculentoside A (EsA) on radiation-induced cutaneous and fibrovascular toxicity and its possible molecular mechanisms, both in vivo and in vitro. Methods and Materials: Mice received drug intervention 18 hours before 30 Gy to the right hind leg. Alterations in several cytokines expressed in skin tissue 2 days after irradiation were determined by ELISA. Early skin toxicity was evaluated 3 to 4 weeks after irradiation by skin scoring, and both tissue contraction and expression of TGF-{beta}1 were determined for soft-tissue fibrosis 3 months after irradiation. In vitro, the effect of EsA on radiation-induced nitric oxide (NO) and cytokine production in different cell types was measured by application of 2, 4, and 8 Gy. Results: In vivo, EsA reduced levels of IL-1{alpha}, MCP-1, VEGF, and TGF-{beta}1 in cutaneous tissue and reduced soft-tissue toxicity. In vitro, EsA inhibited the IL-1{alpha} ordinarily produced after 4 Gy in A431 cells. In Raw264.7 cells, EsA reduced levels of IL-1{alpha}, IL-1{beta}, and NO production costimulated by radiation and lipopolysaccharide (LPS). In L-929 cells, EsA inhibited VEGF, TNF, and MCP-1 production at 2, 4, and 8 Gy. Conclusions: Esculentoside A protects soft tissues against radiation toxicity through inhibiting the production of several proinflammatory cytokines and inflammatory mediators in epithelial cells, macrophages, fibroblasts, and skin tissue.

  14. Sorafenib Enhances Radiation-Induced Apoptosis in Hepatocellular Carcinoma by Inhibiting STAT3

    SciTech Connect

    Huang, Chao-Yuan; Lin, Chen-Si; Tai, Wei-Tien; Hsieh, Chi-Ying; Shiau, Chung-Wai; Cheng, Ann-Lii; Chen, Kuen-Feng

    2013-07-01

    Purpose: Hepatocellular carcinoma (HCC) is one of the most common and lethal human malignancies. Lack of efficient therapy for advanced HCC is a pressing problem worldwide. This study aimed to determine the efficacy and mechanism of combined sorafenib and radiation therapy treatment for HCC. Methods and Materials: HCC cell lines (PLC5, Huh-7, Sk-Hep1, and Hep3B) were treated with sorafenib, radiation, or both, and apoptosis and signal transduction were analyzed. Results: All 4 HCC cell lines showed resistance to radiation-induced apoptosis; however, this resistance could be reversed in the presence of sorafenib. Inhibition of phospho-STAT3 was found in cells treated with sorafenib or sorafenib plus radiation and subsequently reduced the expression levels of STAT3-related proteins, Mcl-1, cyclin D1, and survivin. Silencing STAT3 by RNA interference overcame apoptotic resistance to radiation in HCC cells, and the ectopic expression of STAT3 in HCC cells abolished the radiosensitizing effect of sorafenib. Moreover, sorafenib plus radiation significantly suppressed PLC5 xenograft tumor growth. Conclusions: These results indicate that sorafenib sensitizes resistant HCC cells to radiation-induced apoptosis via downregulating phosphorylation of STAT3 in vitro and in vivo.

  15. Pharyngeal-cervical-brachial variant of Guillain-Barre syndrome.

    PubMed

    Wakerley, Benjamin R; Yuki, Nobuhiro

    2014-03-01

    The pharyngeal-cervical-brachial (PCB) variant of Guillain-Barré syndrome is defined by rapidly progressive oropharyngeal and cervicobrachial weakness associated with areflexia in the upper limbs. Serial nerve conduction studies suggest that PCB represents a localised subtype of Guillain-Barré syndrome characterised by axonal rather than demyelinating neuropathy. Many neurologists are unfamiliar with PCB, which is often misdiagnosed as brainstem stroke, myasthenia gravis or botulism. The presence of additional ophthalmoplegia and ataxia indicates overlap with Fisher syndrome. Half of patients with PCB carry IgG anti-GT1a antibodies which often cross-react with GQ1b, whereas most patients with Fisher syndrome carry IgG anti-GQ1b antibodies which always cross-react with GT1a. Significant overlap between the clinical and serological profiles of these patients supports the view that PCB and Fisher syndrome form a continuous spectrum. In this review, we highlight the clinical features of PCB and outline new diagnostic criteria.

  16. Radiation-induced division delay in Chinese hamster ovary fibroblast and carcinoma cells: dose effect and ploidy. [X-ray

    SciTech Connect

    Kimler, B.F.; Leeper, D.B.; Schneiderman, M.H.

    1981-02-01

    The mitotic selection procedure for cell cycle analysis was utilized to investigate the G/sub 2/ transition point for and the duration of radiation-induced division delay in diploid and tetraploid Chinese hamster ovary (CHO) fibroblasts and in Chinese hamster ovarian carcinoma cells. The location of the radiation-induced division delay transition point was dose independent at high doses and located approximately 42 min before division. At lower doses only an estimate of the point of blockade was possible; but the G/sub 2/ transition point appeared to be earlier in the cell cycle. The duration of radiation-induced division delay was dose dependent. This response is consistent with a sensitive population of cells in late G/sub 2/ that define the location of the transition point and the length of division delay. There was no difference observed in the dose response for radiation-induced division delay between the pseudotetraploid cell line of CHO and the pseudodiploid parent strain. However, in the cell line derived from a spontaneous Chinese hamster ovarian carcinoma the division delay was 39 +- 4 min/Gy. Therefore, radiation-induced division delay is independent of chromosome ploidy, but can show intraspecies cell line specificity.

  17. Implication of prostaglandins and histamine h1 and h2 receptors in radiation-induced temperature responses of rats

    SciTech Connect

    Kandasamy, S.B.; Hunt, W.A.; Mickley, G.A .

    1988-01-01

    Exposure of rats to 1-15 Gy cobalt 60 gamma radiation induced hyperthermia, whereas 20-200 Gy induced hypothermia. Exposure either to the head or to the whole body to 10 Gy induced hyperthermia, while body-only exposure produced hypothermia. This observation indicates that radiation-induced fever is a result of a direct effect on the brain. The hyperthermia due to 10 Gy was significantly attenuated by the pre- or post-treatment with a cyclooxgenase inhibitor, indomethacin. Hyperthermia was also altered by the central administration of a mu receptor antagonist naloxone but only at low doses of radiation. These findings suggest that radiation-induced hyperthermia may be mediated through the synthesis and release of prostaglandins in the brain and to a lesser extent to the release of endogenous opioid peptides. The release of histamine acting on H(1) and H(2) receptors may be involved in radiation-induced hypothermia since both the H(1) receptor antagonist, mepyramine, and H(2) receptor antagonist, cimetidine, antagonized the hypothermia. The results of these studies suggested that the release of neurohumoral substances induced by exposure to ionizing radiation is dose dependent and has different consequences on physiological processes such as the regulation of body temperature. Furthermore, the antagonism of radiation-induced hyperthermia by indomethacin may have potential therapeutic implications in the treatment of fever resulting from accidental irradiations.

  18. Sialylation of Integrin beta1 is Involved in Radiation-Induced Adhesion and Migration in Human Colon Cancer Cells

    SciTech Connect

    Lee, Minyoung; Lee, Hae-June; Seo, Woo Duck; Park, Ki Hun; Lee, Yun-Sil

    2010-04-15

    Purpose: Previously, we reported that radiation-induced ST6 Gal I gene expression was responsible for an increase of integrin beta1 sialylation. In this study, we have further investigated the function of radiation-mediated integrin beta1 sialylation in colon cancer cells. Methods and Materials: We performed Western blotting and lectin affinity assay to analyze the expression and level of sialylated integrin beta1. After exposure to ionizing radiation (IR), adhesion and migration of cells were measured by in vitro adhesion and migration assay. Results: IR increased sialylation of integrin beta1 responsible for its increased protein stability and adhesion and migration of colon cancer cells. However, for cells with an N-glycosylation site mutant of integrin beta1 located on the I-like domain (Mu3), these effects were dramatically inhibited. In addition, integrin beta1-mediated radioresistance was not observed in cells containing this mutant. When sialylation of integrin beta1 was targeted with a sulfonamide chalcone compound, inhibition of radiation-induced sialylation of integrin beta1 and inhibition of radiation-induced adhesion and migration occurred. Conclusion: The increase of integrin beta1 sialylation by ST6 Gal I is critically involved in radiation-mediated adhesion and migration of colon cancer cells. From these findings, integrin beta1 sialylation may be a novel target for overcoming radiation-induced survival, especially radiation-induced adhesion and migration.

  19. The suppression of radiation-induced NF-{kappa}B activity by dexamethasone correlates with increased cell death in vivo

    SciTech Connect

    Nam, Seon Young; Chung, Hee-Yong . E-mail: hychung@hanyang.ac.kr

    2005-10-21

    In this study, we show that dexamethasone treatment increases ionizing radiation-induced cell death by inducing the inhibitory {kappa}B{alpha} (I{kappa}B{alpha}) pathway in mice. The effect of dexamethasone on radiation-induced cell death was assessed by changes in total spleen cellularity and bone marrow colony-forming unit-granulocyte-macrophage (CFU-GM) contents after total body irradiation. While in vivo treatment of mice with dexamethasone alone (1 mg/kg/day, for 2 days) failed to elicit cell death in spleen cells, the combined treatment with dexamethasone (1 mg/kg/day, for 2 days) and {gamma}-rays (1 or 5 Gy) caused a 50-80% reduction in total cellularity in spleen and CFU-GM contents in bone marrow. These results demonstrate that dexamethasone has a synergistic effect on radiation-induced cellular damages in vivo. Immunoblot analysis showed that dexamethasone treatment significantly increases I{kappa}B{alpha} expression in the spleens of irradiated mice. In addition, the dexamethasone treatment significantly reduced radiation-induced nuclear translocation of the nucleus factor-{kappa}B in the spleens of irradiated mice. These results indicate that dexamethasone treatment in vivo may increase radiation-induced cell damages by increasing I{kappa}B{alpha} expression in hematopoietic organs such as spleen and bone marrow.

  20. Repeated Autologous Bone Marrow-Derived Mesenchymal Stem Cell Injections Improve Radiation-Induced Proctitis in Pigs

    PubMed Central

    Busson, Elodie; Holler, Valerie; Strup-Perrot, Carine; Lacave-Lapalun, Jean-Victor; Lhomme, Bruno; Prat, Marie; Devauchelle, Patrick; Sabourin, Jean-Christophe; Simon, Jean-Marc; Bonneau, Michel; Lataillade, Jean-Jacques; Benderitter, Marc

    2013-01-01

    The management of proctitis in patients who have undergone very-high-dose conformal radiotherapy is extremely challenging. The fibrosis-necrosis, fistulae, and hemorrhage induced by pelvic overirradiation have an impact on morbidity. Augmenting tissue repair by the use of mesenchymal stem cells (MSCs) may be an important advance in treating radiation-induced toxicity. Using a preclinical pig model, we investigated the effect of autologous bone marrow-derived MSCs on high-dose radiation-induced proctitis. Irradiated pigs received repeated intravenous administrations of autologous bone marrow-derived MSCs. Immunostaining and real-time polymerase chain reaction analysis were used to assess the MSCs' effect on inflammation, extracellular matrix remodeling, and angiogenesis, in radiation-induced anorectal and colon damages. In humans, as in pigs, rectal overexposure induces mucosal damage (crypt depletion, macrophage infiltration, and fibrosis). In a pig model, repeated administrations of MSCs controlled systemic inflammation, reduced in situ both expression of inflammatory cytokines and macrophage recruitment, and augmented interleukin-10 expression in rectal mucosa. MSC injections limited radiation-induced fibrosis by reducing collagen deposition and expression of col1a2/col3a1 and transforming growth factor-β/connective tissue growth factor, and by modifying the matrix metalloproteinase/TIMP balance. In a pig model of proctitis, repeated injections of MSCs effectively reduced inflammation and fibrosis. This treatment represents a promising therapy for radiation-induced severe rectal damage. PMID:24068742

  1. Efficacy of hyperbaric oxygen therapy in patients with radiation-induced rectal ulcers: A report of five cases.

    PubMed

    Yoshimizu, Shoichi; Chino, Akiko; Miyamoto, Yuji; Tagao, Fuyuki; Iwasaki, Susumu; Ide, Daisuke; Tamegai, Yoshiro; Igarashi, Masahiro; Saito, Shoichi; Fujisaki, Junko

    2017-03-28

    For decades, hyperbaric oxygen therapy has been considered a treatment option in patients with chronic radiation-induced proctitis after pelvic radiation therapy. Refractory cases of chronic radiation-induced proctitis include ulceration, stenosis, and intestinal fistulas with perforation. Appropriate treatment needs to be administered. In this study, we assessed the efficacy of hyperbaric oxygen therapy in five patients with radiation-induced rectal ulcers. Significant improvement and complete ulcer resolution was observed in all treated patients; no side effects were reported. Hyperbaric oxygen therapy has a low toxicity profile and appears to be highly effective in patients with radiation-induced rectal ulcers. However, hyperbaric oxygen therapy alone failed to improve telangiectasia and easy bleeding in four of five patients; these patients were further treated with argon plasma coagulation. Although hyperbaric oxygen therapy may be effective in healing patients with ulcers, it seems inadequate in cases that easy bleeding. Altogether, these data suggest that combination therapy with hyperbaric oxygen therapy and argon plasma coagulation may be an effective and safe treatment strategy in patients with radiation-induced rectal ulcers. This article is protected by copyright. All rights reserved.

  2. Bilateral Brachial Plexus Home Going Catheters After Digital Amputation for Patient With Upper Extremity Digital Gangrene

    PubMed Central

    Abd-Elsayed, Alaa A; Seif, John; Guirguis, Maged; Zaky, Sherif; Mounir-Soliman, Loran

    2011-01-01

    Peripheral nerve catheter placement is used to control surgical pain. Performing bilateral brachial plexus block with catheters is not frequently performed; and in our case sending patient home with bilateral brachial plexus catheters has not been reported up to our knowledge. Our patient is a 57 years old male patient presented with bilateral upper extremity digital gangrene on digits 2 through 4 on both sides with no thumb involvement. The plan was to do the surgery under sequential axillary blocks. On the day of surgery a right axillary brachial plexus block was performed under ultrasound guidance using 20 ml of 0.75% ropivacaine. Patient was taken to the OR and the right fingers amputation was carried out under mild sedation without problems. Left axillary brachial plexus block was then done as the surgeon was closing the right side, two hours after the first block was performed. The left axillary block was done also under ultrasound using 20 ml of 2% mepivacaine. The brachial plexus blocks were performed in a sequential manner. Surgery was unremarkable, and patient was transferred to post anesthetic care unit in stable condition. Over that first postoperative night, the patient complained of severe pain at the surgical sites with minimal pain relief with parentral opioids. We placed bilateral brachial plexus catheters (right axillary and left infra-clavicular brachial plexus catheters). Ropivacaine 0.2% infusion was started at 7 ml per hour basal rate only with no boluses on each side. The patient was discharged home with the catheters in place after receiving the appropriate education. On discharge both catheters were connected to a single ON-Q (I-flow Corporation, Lake Forest, CA) ball pump with a 750 ml reservoir using a Y connection and were set to deliver a fixed rate of 7 ml for each catheter. The brachial plexus catheters were removed by the patient on day 5 after surgery without any difficulty. Patient's postoperative course was otherwise unremarkable

  3. Use of a Collagen-Based Device for Closure of Low Brachial Artery Punctures

    SciTech Connect

    Belenky, A. Aranovich, D.; Greif, F.; Bachar, G.; Bartal, G.; Atar, E.

    2007-04-15

    Purpose. To report our experience with the Angioseal vascular closure device for hemostasis of distal brachial artery puncture. Methods. Between September 2003 and August 2005, 64 Angioseal vascular closure devices were inserted in 64 patients (40 men, 24 women; mean age 65 years) immediately after diagnostic or therapeutic arterial angiographies performed through a 5 Fr to 7 Fr sheath via the distal brachial artery. Ultrasound examination of the brachial artery preceded the angiography in all cases and only arteries wider than 4 mm were closed by the Angioseal. In cases of a sonographically evident thin subcutaneous space of the cubital fossa, tissue tumescence, using 1% Lidocaine, was performed prior to the arterial closure. Results. The deployment success rate was 100%. No major complications were encountered; only 2 patients developed puncture site hematoma, and these were followed conservatively. Conclusions. Closure of low brachial artery punctures with the Angioseal is simple and safe. No additional manual compression is required. We recommend its use after brachial artery access interventions, through appropriately wide arteries, to improve early patient ambulation and potentially reduce possible puncture site complications.

  4. Genetic contribution to brachial artery flow-mediated dilation: The Northern Manhattan Family Study

    PubMed Central

    Suzuki, Keiko; Juo, Suh-Hang Hank; Rundek, Tanja; Boden-Albala, Bernadette; Disla, Norbelina; Liu, Rui; Park, Naeun; Di Tullio, Marco R.; Sacco, Ralph L.; Homma, Shunichi

    2007-01-01

    Background Brachial artery flow-mediated dilation (FMD) is a non-invasive measure of endothelial function. Endothelial dysfunction has been associated with traditional vascular risk factors and increased risk of cardiovascular disease. The importance of genetic contribution to FMD and baseline brachial artery diameter has not been shown in Hispanic populations. The purpose of this study was to estimate the heritability of FMD. Methods Flow mediated dilation and brachial artery diameter were measured in a subset of Caribbean Hispanic families from the ongoing Northern Manhattan Family Study (NOMAFS), which studies the contribution of genetics to stroke and cardiovascular risk factors. The age- and sex-adjusted heritability of FMD was estimated using variance component methods. Results The current data include 620 subjects (97 probands and 523 relatives) from 97 families. The age and sex-adjusted heritability of brachial artery diameter was 0.57 (p < 0.01). The age- and sex-adjusted heritability of FMD was 0.20 (p = 0.01). After additional adjustment for systolic and diastolic blood pressure, body mass index, smoking, lipid, diabetes mellitus, medication, and baseline brachial artery diameter, the heritability of FMD was 0.17 (p = 0.01). Conclusions We found modest heritability of FMD. FMD might be a reasonable phenotype for further investigation of genetic contribution to atherosclerosis. PMID:17462653

  5. Above Elbow Amputation Under Brachial Plexus Block at Supraclavicular and Interscalene Levels

    PubMed Central

    Ahmad, Hassan; Yadagiri, Manjula; Macrosson, Duncan; Majeed, Amer

    2015-01-01

    Introduction: The brachial plexus block is a commonly performed procedure in the anesthetic practice today. It is performed for analgesia as well as anesthesia for upper limb procedures. It has been used for amputation and replantation surgeries of the upper limb. Case presentation: We present the case of a 68-year-old gentleman who had brachial plexus block at supraclavicular and interscalene levels as the sole anesthetic for undergoing above elbow amputation. He was deemed to be very high risk for a general anesthetic as he suffered from severe chronic obstructive pulmonary disease (COPD) and a very poor exercise tolerance (NYHA Class III). The supraclavicular brachial plexus block was supplemented with an interscalene brachial plexus block due to inadequate surgical anesthesia encountered with the former. The procedure was successfully completed under regional anesthesia. Conclusions: The brachial plexus block can be performed at different levels in the same patient to achieve desired results, while employing sound anatomical knowledge and adhering to the maximum safe dose limit of the local anesthetic. PMID:26705518

  6. Trifurcation of superficial brachial artery: a rare case with its clinico-embryological implications.

    PubMed

    Gupta, N; Anshu, A; Dada, R

    2014-01-01

    Literatures on vasculature of upper limbs are crammed with reports of distinctly deviant version of normally prevalent vessels having modified origins, altered branching and odd courses. A unique anatomical variation in vascular pattern was observed during routine dissection of right upper limb in gross anatomy laboratory, AIIMS, New Delhi, India. The brachial artery was placed superficial to median nerve in the arm and therefore it was called superficial brachial artery. In the cubital fossa, 2.8 cm distal to intercondylar line of elbow joint, this superficial brachial artery terminated by trifurcation into radial, common interosseous and ulnar branches. Strikingly the ulnar branch, after its origin ran superficially over the median nerve and epitrochlear superficial flexor group of muscles of forearm in succession for the initial third of its course in the forearm, consequently it was addressed as superficial ulnar artery. The existence of superficial brachial artery in place of normal brachial artery, its termination by trifurcation into radial, common interosseous and superficial ulnar arteries with remarkably different courses, leads to confusing disposition of structures in the arm, cubital fossa and in the forearm and collectively makes this myriad of anatomical variations even rarer. The clinico-embryological revelations for combination of these unconventional observations, apprises and guides the specialized medical personnel attempting blind and invasive procedures in brachium and ante-brachium. This case report depicts the anatomical perspective and clinical implications on confronting a rare variant vasculature architecture pattern of upper limb.

  7. Opposite effects of WR-2721 and WR-1065 on radiation-induced hypothermia: possible correlation with oxygen uptake. Scientific report

    SciTech Connect

    Kandasamy, S.B.; Kumar, K.S.; Hunt, W.A.; Weiss, J.F.

    1988-01-01

    Ionizing radiation induces hypothermia in guinea pigs. While systemic injection of the radioprotectant S-2-(3-aminopropylamimo)ethylphosphorothioic acid (WR-2721) did not block hypothermia induced by exposure to 10 Gy of gamma radiation, central administration did attenuate it. The dephosphorylated metabolite of WR-2721, N-(2-mercaptoethyl)-1,3-diaminopropane (WR-1065), accentuated radiation-induced hypothermia by both routes of administration. In brain homogenates, oxygen uptake was inhibited by WR-2721 but elevated by WR-1065. These results suggest that the antagonism of radiation-induced hypothermia found only after central administration of WR-2721 is due to its direct actions and not in its dephosphorylated metabolite, and that this effect may be correlated with the inhibition by WR-2721 of oxygen uptake.

  8. Opposite effects of WR-2721 and WR-1065 on radiation-induced hypothermia: possible correlation with oxygen uptake

    SciTech Connect

    Kandasamy, S.B.; Kumar, K.S.; Hunt, W.A.; Weiss, J.F.

    1988-05-01

    Ionizing radiation induces hypothermia in guinea pigs. While systemic injection of the radioprotectant S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) did not block hyperthermia induced by exposure to 10 Gy of gamma radiation, central administration did attenuate it. The dephosphorylated metabolite of WR-2721, N-(2-mercaptoethyl)-1,3-diaminopropane (WR-1065), accentuated radiation-induced hypothermia by both routes of administration. In brain homogenates, oxygen uptake was inhibited by WR-2721 but elevated by WR-1065. These results suggest that the antagonism of radiation-induced hypothermia found only after central administration of WR-2721 is due to its direct actions and not to its dephosphorylated metabolite and that this effect may be correlated with the inhibition by WR-2721 of oxygen uptake.

  9. Radiation-induced inflammatory markers of brain injury are modulated by PPARdelta activation in vitro and in vivo

    NASA Astrophysics Data System (ADS)

    Schnegg, Caroline Isabel

    As a result of improvements in cancer therapy and health care, the population of long-term cancer survivors is growing. For these approximately 12 million long-term cancer survivors, brain metastases are a significant risk. Fractionated partial or whole-brain irradiation (fWBI) is often required to treat both primary and metastatic brain cancer. Radiation-induced normal tissue injury, including progressive cognitive impairment, however, can significantly affect the well-being of the approximately 200,000 patients who receive these treatments each year. Recent reports indicate that radiation-induced brain injury is associated with chronic inflammatory and oxidative stress responses, as well as increased microglial activation in the brain. Anti-inflammatory drugs may, therefore, be a beneficial therapy to mitigate radiation-induced brain injury. We hypothesized that activation of peroxisomal proliferator activated receptor delta (PPARō) would prevent or ameliorate radiation-induced brain injury, including cognitive impairment, in part, by alleviating inflammatory responses in microglia. For our in vitro studies, we hypothesized that PPARō activation would prevent the radiation-induced inflammatory response in microglia following irradiation. Incubating BV-2 murine microglial cells with the (PPAR)ō agonist, L-165041, prevented the radiation-induced increase in: i) intracellular ROS generation, ii) Cox-2 and MCP-1 expression, and iii) IL-1β and TNF-α message levels. This occured, in part, through PPARō-mediated modulation of stress activated kinases and proinflammatory transcription factors. PPARō inhibited NF-κB via transrepression by physically interacting with the p65 subunit, and prevented activation of the PKCα/MEK1/2/ERK1/2/AP-1 pathway by inhibiting the radiation-induced increase in intracellular ROS generation. These data support the hypothesis that PPARō activation can modulate the radiation-induced oxidative stress and inflammatory

  10. Protection of radiation induced DNA and membrane damages by total triterpenes isolated from Ganoderma lucidum (Fr.) P. Karst.

    PubMed

    Smina, T P; Maurya, D K; Devasagayam, T P A; Janardhanan, K K

    2015-05-25

    The total triterpenes isolated from the fruiting bodies of Ganoderma lucidum was examined for its potential to prevent γ-radiation induced membrane damage in rat liver mitochondria and microsomes. The effects of total triterpenes on γ-radiation-induced DNA strand breaks in pBR 322 plasmid DNA in vitro and human peripheral blood lymphocytes ex vivo were evaluated. The protective effect of total triterpenes against γ-radiation-induced micronuclei formations in mice bone marrow cells in vivo were also evaluated. The results indicated the significant effectiveness of Ganoderma triterpenes in protecting the DNA and membrane damages consequent to the hazardous effects of radiation. The findings suggest the potential use of Ganoderma triterpenes in radio therapy.

  11. 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

  12. Alpha Lipoic Acid Attenuates Radiation-Induced Thyroid Injury in Rats

    PubMed Central

    Jung, Jung Hwa; Jung, Jaehoon; Kim, Soo Kyoung; Woo, Seung Hoon; Kang, Ki Mun; Jeong, Bae-Kwon; Jung, Myeong Hee; Kim, Jin Hyun; Hahm, Jong Ryeal

    2014-01-01

    Exposure of the thyroid to radiation during radiotherapy of the head and neck is often unavoidable. The present study aimed to investigate the protective effect of α-lipoic acid (ALA) on radiation-induced thyroid injury in rats. Rats were randomly assigned to four groups: healthy controls (CTL), irradiated (RT), received ALA before irradiation (ALA + RT), and received ALA only (ALA, 100 mg/kg, i.p.). ALA was treated at 24 h and 30 minutes prior to irradiation. The neck area including the thyroid gland was evenly irradiated with 2 Gy per minute (total dose of 18 Gy) using a photon 6-MV linear accelerator. Greater numbers of abnormal and unusually small follicles in the irradiated thyroid tissues were observed compared to the controls and the ALA group on days 4 and 7 after irradiation. However, all pathologies were decreased by ALA pretreatment. The quantity of small follicles in the irradiated rats was greater on day 7 than day 4 after irradiation. However, in the ALA-treated irradiated rats, the numbers of small and medium follicles were significantly decreased to a similar degree as in the control and ALA-only groups. The PAS-positive density of the colloid in RT group was decreased significantly compared with all other groups and reversed by ALA pretreatment. The high activity index in the irradiated rats was lowered by ALA treatment. TGF-ß1 immunoreactivity was enhanced in irradiated rats and was more severe on the day 7 after radiation exposure than on day 4. Expression of TGF-ß1 was reduced in the thyroid that had undergone ALA pretreatment. Levels of serum pro-inflammatory cytokines (TNF-α, IL-1ß and IL-6) did not differ significantly between the all groups. This study provides that pretreatment with ALA decreased the severity of radiation-induced thyroid injury by reducing inflammation and fibrotic infiltration and lowering the activity index. Thus, ALA could be used to ameliorate radiation-induced thyroid injury. PMID:25401725

  13. Extracellular Vesicles Mediate Radiation-Induced Systemic Bystander Signals in the Bone Marrow and Spleen

    PubMed Central

    Szatmári, Tünde; Kis, Dávid; Bogdándi, Enikő Noémi; Benedek, Anett; Bright, Scott; Bowler, Deborah; Persa, Eszter; Kis, Enikő; Balogh, Andrea; Naszályi, Lívia N.; Kadhim, Munira; Sáfrány, Géza; Lumniczky, Katalin

    2017-01-01

    Radiation-induced bystander effects refer to the induction of biological changes in cells not directly hit by radiation implying that the number of cells affected by radiation is larger than the actual number of irradiated cells. Recent in vitro studies suggest the role of extracellular vesicles (EVs) in mediating radiation-induced bystander signals, but in vivo investigations are still lacking. Here, we report an in vivo study investigating the role of EVs in mediating radiation effects. C57BL/6 mice were total-body irradiated with X-rays (0.1, 0.25, 2 Gy), and 24 h later, EVs were isolated from the bone marrow (BM) and were intravenously injected into unirradiated (so-called bystander) animals. EV-induced systemic effects were compared to radiation effects in the directly irradiated animals. Similar to direct radiation, EVs from irradiated mice induced complex DNA damage in EV-recipient animals, manifested in an increased level of chromosomal aberrations and the activation of the DNA damage response. However, while DNA damage after direct irradiation increased with the dose, EV-induced effects peaked at lower doses. A significantly reduced hematopoietic stem cell pool in the BM as well as CD4+ and CD8+ lymphocyte pool in the spleen was detected in mice injected with EVs isolated from animals irradiated with 2 Gy. These EV-induced alterations were comparable to changes present in the directly irradiated mice. The pool of TLR4-expressing dendritic cells was different in the directly irradiated mice, where it increased after 2 Gy and in the EV-recipient animals, where it strongly decreased in a dose-independent manner. A panel of eight differentially expressed microRNAs (miRNA) was identified in the EVs originating from both low- and high-dose-irradiated mice, with a predicted involvement in pathways related to DNA damage repair, hematopoietic, and immune system regulation, suggesting a direct involvement of these pathways in mediating radiation-induced

  14. The flavonolignan-silymarin protects enzymatic, hematological, and immune system against γ-radiation-induced toxicity.

    PubMed

    Adhikari, Manish; Arora, Rajesh

    2016-06-01

    The main focus of this study is evaluation of radioprotective efficacy of silymarin, a flavonolignan, against γ-radiation-induced damage to hematological, vital organs (liver and intestine), and immune system. Survival studies revealed that silymarin (administered orally for 3 days) provided maximum protection (67%) at 70 mg/kg body weight (b.wt.) against lethal 9 Gy γ-irradiation (dose reduction factor = 1.27). The study revealed significant (p < 0.05) changes in levels of catalase (12.57 ± 2.58 to 30.24 ± 4.89 units), glutathione peroxidase (6.23 ± 2.95 to 13.26 ± 1.36 µg of reduced glutathione consumed/min/mg protein), glutathione reductase (0.25 ± 5.6 to 11.65 ± 2.83 pM NADPH consumed/min/mg protein), and superoxide dismutase (11.74 ± 0.2 to 16.09 ± 3.47 SOD U/mg of protein) activity at 30th day. Silymarin pretreated irradiated group exhibited increased proliferation in erythrocyte count (1.76 ± 0.41 × 10(6) to 9.25 ± 0.24 × 10(6) ), hemoglobin (2.15 ± 0.48g/dL to 14.77 ± 0.25g/dL), hematocrit (4.55 ± 0.24% to 37.22 ± 0.21%), and total leucocyte count (1.4 ± 0.15 × 10(6) to 8.31 ± 0.47 × 10(6) ) as compared with radiation control group on 15th day. An increase in CD4:CD8 ratio was witnessed (0.2-1%) at 30th day time interval using flow cytometry. Silymarin also countered radiation-induced decrease (p < 0.05) in regulatory T-cells (Tregs ) (11.23% in radiation group at 7th day versus 0.1% in pretreated silymarin irradiated group at 15th day). The results of this study indicate that flavonolignan-silymarin protects enzymatic, hematological, and immune system against γ-radiation-induced toxicity and might prove useful in management of nuclear and radiological emergencies. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 641-654, 2016.

  15. Selective inhibition of microglia-mediated neuroinflammation mitigates radiation-induced cognitive impairment.

    PubMed

    Jenrow, Kenneth A; Brown, Stephen L; Lapanowski, Karen; Naei, Hoda; Kolozsvary, Andrew; Kim, Jae Ho

    2013-05-01

    Cognitive impairment precipitated by irradiation of normal brain tissue is commonly associated with radiation therapy for treatment of brain cancer, and typically manifests more than 6 months after radiation exposure. The risks of cognitive impairment are of particular concern for an increasing number of long-term cancer survivors. There is presently no effective means of preventing or mitigating this debilitating condition. Neuroinflammation mediated by activated microglial cytokines has been implicated in the pathogenesis of radiation-induced cognitive impairment in animal models, including the disruption of neurogenesis and activity-induced gene expression in the hippocampus. These pathologies evolve rapidly and are associated with relatively subtle cognitive impairment at 2 months postirradiation. However, recent reports suggest that more profound cognitive impairment develops at later post-irradiation time points, perhaps reflecting a gradual loss of responsiveness within the hippocampus by the disruption of neurogenesis. We hypothesized that inhibiting neuroinflammation using MW01-2-151SRM (MW-151), a selective inhibitor of proinflammatory cytokine production, might mitigate these deleterious radiation effects by preserving/restoring hippocampal neurogenesis. MW-151 therapy was initiated 24 h after 10 Gy whole-brain irradiation (WBI) administered as a single fraction and maintained for 28 days thereafter. Proinflammatory activated microglia in the dentate gyrus were assayed at 2 and 9 months post-WBI. Cell proliferation and neurogenesis in the dentate gyrus were assayed at 2 months post-WBI, whereas novel object recognition and long-term potentiation were assayed at 6 and 9 months post-WBI, respectively. MW-151 mitigated radiation-induced neuroinflammation at both early and late time points post-WBI, selectively mitigated the deleterious effects of irradiation on hippocampal neurogenesis, and potently mitigated radiation-induced deficits of novel object

  16. Dietary Supplement Attenuates Radiation-Induced Osteoclastogenic and Oxidative Stress-Related Responses and Protects Adult Mice from Radiation-Induced Bone Loss

    NASA Technical Reports Server (NTRS)

    Globus, Ruth; Schreurs, Ann-Sofie; Tahimic, Candice; Shirazi-Fard, Yasaman; Alwood, Joshua; Shahnazari, Mohammed; Halloran, Bernard

    2015-01-01

    Our central hypothesis is that oxidative stress plays a key role in cell dysfunction and progressive bone loss caused by radiation exposure during spaceflight. In animal studies, excess free radical formation is associated with pathological changes in bone structure, enhanced bone resorption, reduced bone formation and decreased bone mineral density, which can lead to skeletal fragility. We previously reported that exposure to low or high-LET radiation rapidly increases expression levels of pro-osteoclastogenic and oxidative stress-related genes in bone and marrow, followed by pathological changes in skeletal structure. To screen various antioxidants for radioprotective effects on bone, 4 month old, male C57Bl6/J mice were treated with a dietary antioxidant cocktail, injectable alpha-lipoic acid, or a dried plum-enriched diet (DP). Mice were then exposed to 2Gy 137Cs total body radiation and one day later marrow cells were collected and the relevant genes analyzed for expression levels. Of the candidates tested, DP was most effective in reducing bone resorption-related gene expression. Microcomputed tomography revealed that DP also prevented the radiation-induced deterioration of skeletal microarchitecture, as indicated by percent bone volume, trabecular spacing and trabecular number. DP had similar protective effects on skeletal structure after sequential exposure to protons (0.5 Gy, 150MeV/n) and 56Fe 0.5Gy, 600 MeV/n). When cultured ex vivo under osteogenic conditions, bone marrow-derived cells from DP-fed animals exhibited increased colony numbers compared to control diet-fed animals. These findings suggest that DP exerted pro-osteogenic effects apart from previously identified anti-resorptive actions, which may contribute to radioprotection of skeletal tissue. In conclusion, a diet enriched in certain types of antioxidants and polyphenols such as DP may be useful as an intervention to protect tissues from degenerative effects of ionizing radiation.

  17. Effects of Pharmacological Inhibition and Genetic Deficiency of Plasminogen Activator Inhibitor-1 in Radiation-Induced Intestinal Injury

    SciTech Connect

    Abderrahmani, Rym; Francois, Agnes; Buard, Valerie; Benderitter, Marc; Sabourin, Jean-Christophe; Crandall, David L.; Milliat, Fabien

    2009-07-01

    Purpose: To investigate effects of plasminogen activator inhibitor 1 (PAI-1) genetic deficiency and pharmacological PAI-1 inhibition with PAI-039 in a mouse model of radiation-induced enteropathy. Methods and Materials: Wild-type (Wt) and PAI-1{sup -/-} knockout mice received a single dose of 19 Gy to an exteriorized localized intestinal segment. Sham and irradiated Wt mice were treated orally with 1 mg/g of PAI-039. Histological modifications were quantified using a radiation injury score. Moreover, intestinal gene expression was monitored by real-time PCR. Results: At 3 days after irradiation, PAI-039 abolished the radiation-induced increase in the plasma active form of PAI-1 and limited the radiation-induced gene expression of transforming growth factor {beta}1 (TGF-{beta}1), CTGF, PAI-1, and COL1A2. Moreover, PAI-039 conferred temporary protection against early lethality. PAI-039 treatment limited the radiation-induced increase of CTGF and PAI-1 at 2 weeks after irradiation but had no effect at 6 weeks. Radiation injuries were less severe in PAI-1{sup -/-} mice than in Wt mice, and despite the beneficial effect, 3 days after irradiation, PAI-039 had no effects on microscopic radiation injuries compared to untreated Wt mice. Conclusions: A genetic deficiency of PAI-1 is associated with amelioration of late radiation enteropathy. Pharmacological inhibition of PAI-1 by PAI-039 positively impacts the early, acute phase increase in plasma PAI-1 and the associated radiation-induced gene expression of inflammatory/extracellular matrix proteins. Since PAI-039 has been shown to inhibit the active form of PAI-1, as opposed to the complete loss of PAI-1 in the knockout animals, these data suggest that a PAI-1 inhibitor could be beneficial in treating radiation-induced tissue injury in acute settings where PAI-1 is elevated.

  18. Patients with Testicular Cancer Undergoing CT Surveillance Demonstrate a Pitfall of Radiation-induced Cancer Risk Estimates: The Timing Paradox

    PubMed Central

    Eisenberg, Jonathan D.; Lee, Richard J.; Gilmore, Michael E.; Turan, Ekin A.; Singh, Sarabjeet; Kalra, Mannudeep K.; Liu, Bob; Kong, Chung Yin; Gazelle, G. Scott

    2013-01-01

    Purpose: To demonstrate a limitation of lifetime radiation-induced cancer risk metrics in the setting of testicular cancer surveillance—in particular, their failure to capture the delayed timing of radiation-induced cancers over the course of a patient’s lifetime. Materials and Methods: Institutional review board approval was obtained for the use of computed tomographic (CT) dosimetry data in this study. Informed consent was waived. This study was HIPAA compliant. A Markov model was developed to project outcomes in patients with testicular cancer who were undergoing CT surveillance in the decade after orchiectomy. To quantify effects of early versus delayed risks, life expectancy losses and lifetime mortality risks due to testicular cancer were compared with life expectancy losses and lifetime mortality risks due to radiation-induced cancers from CT. Projections of life expectancy loss, unlike lifetime risk estimates, account for the timing of risks over the course of a lifetime, which enabled evaluation of the described limitation of lifetime risk estimates. Markov chain Monte Carlo methods were used to estimate the uncertainty of the results. Results: As an example of evidence yielded, 33-year-old men with stage I seminoma who were undergoing CT surveillance were projected to incur a slightly higher lifetime mortality risk from testicular cancer (598 per 100 000; 95% uncertainty interval [UI]: 302, 894) than from radiation-induced cancers (505 per 100 000; 95% UI: 280, 730). However, life expectancy loss attributable to testicular cancer (83 days; 95% UI: 42, 124) was more than three times greater than life expectancy loss attributable to radiation-induced cancers (24 days; 95% UI: 13, 35). Trends were consistent across modeled scenarios. Conclusion: Lifetime radiation risk estimates, when used for decision making, may overemphasize radiation-induced cancer risks relative to short-term health risks. © RSNA, 2012 Supplemental material: http

  19. A Survey of Radiation-Induced Bronchiolitis Obliterans Organizing Pneumonia Syndrome After Breast-Conserving Therapy in Japan

    SciTech Connect

    Ogo, Etsuyo Komaki, Ritsuko; Fujimoto, Kiminori; Uchida, Masafumi; Abe, Toshi; Nakamura, Katsumasa; Mitsumori, Michihide; Sekiguchi, Kenji; Kaneyasu, Yuko; Hayabuchi, Naofumi

    2008-05-01

    Purpose: We observed a rare and unique occurrence of radiation-induced pulmonary injury outside the tangential field for early breast cancer treatment. The findings appeared to be idiopathic and were called radiation-induced bronchiolitis obliterans organizing pneumonia (BOOP) syndrome. We surveyed major hospitals in Japan to review their findings of radiation-induced BOOP, in particular the clinical and pictorial characteristics of the entity. Methods and Materials: We reviewed surveys completed and returned by 20 institutions. The survey responses were based on a total of 37 cases of BOOP syndrome. We also reviewed X-ray and computed tomography scans provided by these institutions. We discussed the information derived from the questionnaire and analyzed patients' characteristics, methods used in the treatment of BOOP syndrome, and prognosis. Results: The incidence of the radiation-induced BOOP syndrome was about 1.8% (37 of 2,056). We did not find a relationship between the characteristics of patients and the occurrence of radiation-induced BOOP syndrome. The pulmonary findings were classified into four patterns on chest computed tomography scans. Progression of the pulmonary lesions observed on chest X-ray was classified into three patterns. Pneumonitis appeared within 6 months after radiotherapy was completed and disappeared within 6-12 months after its onset. At 5-year follow-up, 2 patients had died, 1 of breast cancer and the other of interstitial pneumonitis, which seemed to be idiopathic and unrelated to the radiation-induced BOOP syndrome. Conclusions: Although the incidence of BOOP syndrome and its associated prognosis are not significant, the patients' clinical condition must be carefully followed.

  20. Constraint-Induced Movement Therapy for Children with Obstetric Brachial Plexus Palsy: Two Single-Case Series

    ERIC Educational Resources Information Center

    Buesch, Francisca Eugster

    2010-01-01

    The objective of this pilot study was to investigate the feasibility of constraint-induced movement therapy (CIMT) in children with obstetric brachial plexus palsy and receive preliminary information about functional improvements. Two patients (age 12 years) with obstetric brachial plexus palsy were included for a 126-h home-based CIMT…

  1. Hand Function in Children with an Upper Brachial Plexus Birth Injury: Results of the Nine-Hole Peg Test

    ERIC Educational Resources Information Center

    Immerman, Igor; Alfonso, Daniel T.; Ramos, Lorna E.; Grossman, Leslie A.; Alfonso, Israel; Ditaranto, Patricia; Grossman, John A. I.

    2012-01-01

    Aim: The aim of this study was to evaluate hand function in children with Erb upper brachial plexus palsy. Method: Hand function was evaluated in 25 children (eight males; 17 females) with a diagnosed upper (C5/C6) brachial plexus birth injury. Of these children, 22 had undergone primary nerve reconstruction and 13 of the 25 had undergone…

  2. Comparative study of microwave radiation-induced magnetoresistive oscillations induced by circularly- and linearly- polarized photo-excitation

    PubMed Central

    Ye, Tianyu; Liu, Han-Chun; Wang, Zhuo; Wegscheider, W.; Mani, Ramesh G.

    2015-01-01

    A comparative study of the radiation-induced magnetoresistance oscillations in the high mobility GaAs/AlGaAs heterostructure two dimensional electron system (2DES) under linearly- and circularly- polarized microwave excitation indicates a profound difference in the response observed upon rotating the microwave launcher for the two cases, although circularly polarized microwave radiation induced magnetoresistance oscillations observed at low magnetic fields are similar to the oscillations observed with linearly polarized radiation. For the linearly polarized radiation, the magnetoresistive response is a strong sinusoidal function of the launcher rotation (or linear polarization) angle, θ. For circularly polarized radiation, the oscillatory magnetoresistive response is hardly sensitive to θ. PMID:26450679

  3. Comparative study of microwave radiation-induced magnetoresistive oscillations induced by circularly- and linearly- polarized photo-excitation

    SciTech Connect

    Ye, Tianyu; Liu, Han -Chun; Wang, Zhuo; Wegscheider, W.; Mani, Ramesh G.

    2015-10-09

    A comparative study of the radiation-induced magnetoresistance oscillations in the high mobility GaAs/AlGaAs heterostructure two dimensional electron system (2DES) under linearly- and circularly- polarized microwave excitation indicates a profound difference in the response observed upon rotating the microwave launcher for the two cases, although circularly polarized microwave radiation induced magnetoresistance oscillations observed at low magnetic fields are similar to the oscillations observed with linearly polarized radiation. For the linearly polarized radiation, the magnetoresistive response is a strong sinusoidal function of the launcher rotation (or linear polarization) angle, θ. As a result, for circularly polarized radiation, the oscillatory magnetoresistive response is hardly sensitive to θ.

  4. Reduction of radiation-induced cell cycle blocks by caffeine does not necessarily lead to increased cell killing

    SciTech Connect

    Musk, S.R. )

    1991-03-01

    The effect of caffeine upon the radiosensitivities of three human tumor lines was examined and correlated with its action upon the radiation-induced S-phase and G2-phase blocks. Caffeine was found to reduce at least partially the S-phase and G2-phase blocks in all the cell lines examined but potentiated cytotoxicity in only one of the three tumor lines. That reductions have been demonstrated to occur in the absence of increased cell killing provides supporting evidence for the hypothesis that reductions may not be causal in those cases when potentiation of radiation-induced cytotoxicity is observed in the presence of caffeine.

  5. Post-irradiation dietary vitamin E does not affect the development of radiation-induced lung damage in rats.

    PubMed

    Wiegman, Erwin M; van Gameren, Mieke M; Kampinga, Harm H; Szabó, Ben G; Coppes, Rob P

    2004-07-01

    The purpose of this study was to investigate whether application of post-irradiation vitamin E, an anti-oxidant, could prevent the development of radiation induced lung damage. Wistar rats were given vitamin E enriched or vitamin E deprived food starting from 4 weeks after 18Gy single dose irradiation of the right thorax. Neither breathing frequencies nor CT density measurements revealed differences between the groups. It is concluded that post-irradiation vitamin E does not influence radiation-induced fibrosis to the lung.

  6. Effect of Addition of Fentanyl to Xylocaine Hydrochloride in Brachial Plexus Block by Supraclavicular Approach

    PubMed Central

    Paluvadi, Venkata Raghavendra; Manne, Venkata Sesha Sai Krishna

    2017-01-01

    Aim: This study was designed to quantitatively compare the effects of 1.5% xylocaine with 1.5% xylocaine and fentanyl (1 μg/kg) mixture for supraclavicular brachial plexus block. Materials and Methods: Sixty patients between the age group of 20–60 and scheduled for upper limb surgery were divided into two groups (xylocaine group and xylocaine plus fentanyl group). After performing supraclavicular brachial plexus block, an assessment was made for onset of analgesia, duration and degree of analgesia, block intensity, and for any other side effects. Results: Mean duration of analgesia is Group I is 2.1 h and in Group II is 8.1 h; a four-fold increase in duration of analgesia. Conclusion: Addition of fentanyl to xylocaine for supraclavicular brachial plexus block has no significant effect on onset or quality of analgesia, but duration of analgesia is significantly prolonged. PMID:28298769

  7. Different Learning Curves for Axillary Brachial Plexus Block: Ultrasound Guidance versus Nerve Stimulation

    PubMed Central

    Luyet, C.; Schüpfer, G.; Wipfli, M.; Greif, R.; Luginbühl, M.; Eichenberger, U.

    2010-01-01

    Little is known about the learning of the skills needed to perform ultrasound- or nerve stimulator-guided peripheral nerve blocks. The aim of this study was to compare the learning curves of residents trained in ultrasound guidance versus residents trained in nerve stimulation for axillary brachial plexus block. Ten residents with no previous experience with using ultrasound received ultrasound training and another ten residents with no previous experience with using nerve stimulation received nerve stimulation training. The novices' learning curves were generated by retrospective data analysis out of our electronic anaesthesia database. Individual success rates were pooled, and the institutional learning curve was calculated using a bootstrapping technique in combination with a Monte Carlo simulation procedure. The skills required to perform successful ultrasound-guided axillary brachial plexus block can be learnt faster and lead to a higher final success rate compared to nerve stimulator-guided axillary brachial plexus block. PMID:21318138

  8. Modeling of radiation-induced bystander effect using Monte Carlo methods

    NASA Astrophysics Data System (ADS)

    Xia, Junchao; Liu, Liteng; Xue, Jianming; Wang, Yugang; Wu, Lijun

    2009-03-01

    Experiments showed that the radiation-induced bystander effect exists in cells, or tissues, or even biological organisms when irradiated with energetic ions or X-rays. In this paper, a Monte Carlo model is developed to study the mechanisms of bystander effect under the cells sparsely populated conditions. This model, based on our previous experiment which made the cells sparsely located in a round dish, focuses mainly on the spatial characteristics. The simulation results successfully reach the agreement with the experimental data. Moreover, other bystander effect experiment is also computed by this model and finally the model succeeds in predicting the results. The comparison of simulations with the experimental results indicates the feasibility of the model and the validity of some vital mechanisms assumed.

  9. Radiation-induced biomarkers for the detection and assessment of absorbed radiation doses

    PubMed Central

    Rana, Sudha; Kumar, Raj; Sultana, Sarwat; Sharma, Rakesh Kumar

    2010-01-01

    Radiation incident involving living organisms is an uncommon but a very serious situation. The first step in medical management including triage is high-throughput assessment of the radiation dose received. Radiation exposure levels can be assessed from viability of cells, cellular organelles such as chromosome and different intermediate metabolites. Oxidative damages by ionizing radiation result in carcinogenesis, lowering of the immune response and, ultimately, damage to the hematopoietic system, gastrointestinal system and central nervous system. Biodosimetry is based on the measurement of the radiation-induced changes, which can correlate them with the absorbed dose. Radiation biomarkers such as chromosome aberration are most widely used. Serum enzymes such as serum amylase and diamine oxidase are the most promising biodosimeters. The level of gene expression and protein are also good biomarkers of radiation. PMID:21829314

  10. Lymphocyte lifetime in the rabbit measured by the decline in radiation-induced chromosome damage.

    PubMed

    Decat, G; Leonard, A

    1980-08-01

    The life span of rabbit lymphocytes carrying radiation-induced chromosome aberrations has been studied by following the decline in aberration frequency as a function of the time after irradiation. Female rabbits were given a whole body X-ray dose of 300 rad. The day before exposure and at 2 hours, 14, 28, 42, 56, 84, 140, 250 and 500 days thereafter, blood samples were taken from a marginal ear vein of each animal. A plot of log abnormalities against time suggests an exponential decline for dicentrics and fragments up to 140 days, the half time for dicentrics and fragments being 70 and 46 days respectively. The results of the present investigation thus demonstrate that because of their shorter life span, in vivo observations on aberrations in rabbit lymphocytes are not suitable for extrapolation of information on chronic exposure to man.

  11. Radiation-induced hemopoietic and immune dysfunction. Technical report, 16 Aug 86-31 Mar 90

    SciTech Connect

    Storb, R.; Schuening, F.

    1991-06-01

    This work was aimed at investigating radiation-induced hemopoietic and immune dysfunction in the dog model. One project was to produce monoclonal antibodies directed against canine hemopoietic precursor cells and specific for pluripotent stem cells. Antibodies obtained reacted with different myeloid and erythroid precursor cells; unfortunately, none of the antibodies were specific for pluripotent hemopoietic stem cells. Positive selections for these cells were performed using magnetic beads and an antibody against class 2-antigen. Transplantation of class 2 positive marrow cells into otherwise lethally irradiated dogs led to sustained recovery in only 1 of 5 dogs. A second project established and investigated long-term marrow cultures in the dog. Culture conditions were studied and optimized, and marrow cells were transplanted into otherwise lethally irradiated dogs to investigate stem cell survival in long-term cultures. Engraftment was observed only with short-term marrow cultures.

  12. A Human Espophageal Epithelial Cell Model for Study of Radiation Induced Cancer and DNA Damage Repair

    NASA Technical Reports Server (NTRS)

    Huff, Janice L.; Patel, Zarana S.; Hada, Megumi; Cucinotta, Francis A.

    2008-01-01

    For cancer risk assessment in astronauts and for countermeasure development, it is essential to understand the molecular mechanisms of radiation carcinogenesis and how these mechanisms are influenced by exposure to the types of radiation found in space. We are developing an in vitro model system for the study of radiation-induced initiation and progression of esophageal carcinoma, a type of cancer found to have a significant enhancement in incidence in the survivors of the atomic bomb detonations in Japan. Here we present the results of our preliminary characterization of both normal and hTERT immortalized esophageal epithelial cells grown in 2-dimensional culture. We analyzed DNA repair capacity by measuring the kinetics of formation and loss of - H2AX foci following radiation exposure. Additionally, we analyzed induction of chromosomal aberrations using 3-color fluorescence in situ hybridization (FISH). Data were generated using both low LET (gamma rays) and high LET ions (1000 MeV/nucleon iron).

  13. Polymeric nanocomposite proton exchange membranes prepared by radiation-induced polymerization for direct methanol fuel cell

    NASA Astrophysics Data System (ADS)

    Kim, Young-Seok; Seo, Kwang-Seok; Choi, Seong-Ho

    2016-01-01

    The vinyl group-modified montmorillonite clay (F-MMT), vinyl group-modified graphene oxide (F-GO), and vinyl group-modified multi-walled carbon nanotube (F-MWNT) were first prepared by ion exchange reaction of 1-[(4-ethylphenyl)methyl]-3-butyl-imidazolium chloride in order to use the materials for protection against methanol cross-over in direct methanol fuel cell (DMFC) membrane. Then polymeric nanocomposite membranes with F-MMT, F-GO, and F-MWNT were prepared by the solvent casting method after radiation-induced polymerization of vinyl monomers in water-methanol mixture solvents. The proton conductivity, water uptake, ion-exchange capacity, methanol permeability, and DMFC performance of the polymeric nanocomposite membranes with F-MMT, F-GO, and F-MWNT were evaluated.

  14. Radiation-induced grafting of sweet sorghum stalk for copper(II) removal from aqueous solution.

    PubMed

    Dong, Jing; Hu, Jun; Wang, Jianlong

    2013-11-15

    The influence of main components (cellulose, hemicellulose and lignin) of the sweet sorghum stalk on radiation-induced grafting reaction and adsorption of copper from aqueous solution was investigated. Sweet sorghum stalk was grafted with acrylic acid induced by γ-irradiation. The results showed that the grafted stalk contained 1.6 mmol/g carboxyl groups, and its maximal adsorption capacity was 13.32 mg/g. The cellulose, hemicellulose and lignin of the raw materials were confirmed to involve in grafting reaction through comparing the grafting yield and the structure of the grafted materials. Both the structure and the composition of the sweet sorghum stalk had influence on the grafting reaction and adsorption capacity. The adsorption capacity of the grafted sweet sorghum stalk increased about five times, and the adsorption isotherm of the grafted materials conformed to the Langmuir model. The main mechanism for copper adsorption involved in ion exchange.

  15. Radiation-Induced Centers in Lead Silicate Glasses Irradiated by Stationary and Pulsed Electron Beams

    NASA Astrophysics Data System (ADS)

    Zhidkov, I. S.; Zatsepin, A. F.; Konev, S. F.; Cholakh, S. O.

    2015-08-01

    Radiation-induced centers formed in heavy flint glasses irradiated by electron beams are investigated by the methods of optical and EPR spectroscopy. It is revealed that stable and short-living optical absorption centers of close natures are formed under irradiation by fast electrons. A correlation is established between the stable optical absorption bands and the EPR signals interpreted as signals of the (Pb2+)/h+ hole centers. The shortliving color centers are formed due to short-term distortion of the O-Pb bonds, and the stable centers are formed due to the spatial separation, thermalization, and subsequent stabilization of excited electrons and holes in tails of the localized states. Irradiation by electron beams leads to a change in the spectral characteristics of the fundamental absorption edge and, in particular, of the Urbach energy that determines the degree of structural disorder.

  16. CDK1 Enhances Mitochondrial Bioenergetics for Radiation-Induced DNA Repair

    PubMed Central

    Qin, Lili; Fan, Ming; Candas, Demet; Jiang, Guochun; Papadopoulos, Stelios; Tian, Lin; Woloschak, Gayle; Grdina, David J.; Li, Jian Jian

    2015-01-01

    SUMMARY Nuclear DNA repair capacity is a critical determinant of cell fate under genotoxic stress conditions. DNA repair is a well-defined energy consuming process; however, it is unclear how DNA repair is fueled and whether mitochondrial energy production contributes to nuclear DNA repair. Here, we report a dynamic enhancement of oxygen consumption and mitochondrial ATP generation in irradiated normal cells, paralleled with increased mitochondrial relocation of cell cycle kinase CDK1 and nuclear DNA repair. The basal and radiation-induced mitochondrial ATP generation is significantly reduced in cells harboring CDK1 phosphorylation deficient mutant complex I subunits. Similarly, mitochondrial ATP generation and nuclear DNA repair are also severely compromised in cells harboring mitochondrial-targeted kinase deficient CDK1. These results demonstrate a mechanism governing the communication between mitochondria and nucleus, by which CDK1 boosts mitochondrial bioenergetics to meet the increased cellular fuel demand for DNA repair and cell survival under genotoxic stress. PMID:26670043

  17. Endogenous retrovirus and radiation-induced leukemia in the RMF mouse

    SciTech Connect

    Tennant, R.W.; Boone, L.R.; Lalley, P.; Yang, W.K.

    1982-01-01

    The induction of myeloid leukemia in irradiated RFM/Un mice has been associated with retrovirus infection. However, two characteristics of this strain complicate efforts to define the role of the virus. This strain possesses only one inducible host range class of endogenous virus and a unique gene, in addition to the Fv-1/sup n/ locus, which specifically restricts exogenous infection by endogenous viruses. These characteristics possibly account for absence of recombinant viruses in this strain, even though virus is amply expressed during most of the animal's life span. We have examined further the distribution of retrovirus sequences and the chromosomal locus of the inducible virus in this strain. This report describes evidence for additional viral sequences in cells of a radiation-induced myeloid leukemia line and discusses the possible origin of these added copies.

  18. On the mechanism of radiation-induced polymerization of vinyl monomers in ionic liquid

    NASA Astrophysics Data System (ADS)

    Liu, Yaodong; Wu, Guozhong

    2005-06-01

    An attempt was made to investigate the mechanism controlling the radiation-induced polymerization of vinyl monomers in room temperature ionic liquids. For that purpose, copolymerization of styrene (St) and methyl methacrylate (MMA) was initiated by 60Co gamma radiation in a moisture-stable ionic liquid, [choline chloride][ZnCl 2], and its mixture with THF (4:1 v/v). By analyzing the product composition with FTIR for a series of poly(St-co-MMA) samples, it was found that the mole fraction of St in the copolymer is linearly proportional to the mole fraction of St in the feed. Therefore, radiation polymerization in ionic liquid and its mixture with organic solvent is suggested to be a radical propagating process.

  19. Radiation-inducible immunotherapy for cancer: senescent tumor cells as a cancer vaccine.

    PubMed

    Meng, Yuru; Efimova, Elena V; Hamzeh, Khaled W; Darga, Thomas E; Mauceri, Helena J; Fu, Yang-Xin; Kron, Stephen J; Weichselbaum, Ralph R

    2012-05-01

    Radiotherapy offers an effective treatment for advanced cancer but local and distant failures remain a significant challenge. Here, we treated melanoma and pancreatic carcinoma in syngeneic mice with ionizing radiation (IR) combined with the poly(ADP-ribose) polymerase inhibitor (PARPi) veliparib to inhibit DNA repair and promote accelerated senescence. Based on prior work implicating cytotoxic T lymphocytes (CTLs) as key mediators of radiation effects, we discovered that senescent tumor cells induced by radiation and veliparib express immunostimulatory cytokines to activate CTLs that mediate an effective antitumor response. When these senescent tumor cells were injected into tumor-bearing mice, an antitumor CTL response was induced which potentiated the effects of radiation, resulting in elimination of established tumors. Applied to human cancers, radiation-inducible immunotherapy may enhance radiotherapy responses to prevent local recurrence and distant metastasis.

  20. Asymmetric radiation-induced inclusion polymerization of 3-methyl-1,4-pentadiene in deoxycholic acid

    NASA Astrophysics Data System (ADS)

    Cataldo, Franco; Ursini, Ornella; Angelini, Giancarlo

    2010-01-01

    The radiation-induced polymerization of 3-methyl-1,3-pentadiene (3MPD) as an inclusion complex in deoxycholic acid (DOCA) has produced in good yield the optically active polymer poly(3-methyl-1,4-pentadiene) (P3MPD) whose structure and properties were studied by FT-IR spectroscopy and thermal analysis (TGA, DTG and DTA). The data show that the polymer is essentially trans-1,4-P3MPD as expected for the polymerization in constrained media. Trans-1,4-P3MPD is optically active with [ α] D values comprised between +4.3 and +5.6. The optical rotatory dispersion curve of the P3MPD is completely different from that of DOCA as expected.

  1. Radiation-induced pulmonary arterial perfusion defects: modification by D-penicillamine. [Rats; /sup 60/Co

    SciTech Connect

    Ward, W.F.

    1981-04-01

    D-penicillamine, previously shown to have a beneficial effect on radiation-induced pulmonary histopathology, was tested to determine its effect on function in the irradiated lung. Male rats were irradiated with /sup 60/Co gamma rays; half then received 10 mg D-penicillamine per day, and half received no further treatment. One to nine months after irradiation, animals were subjected to lung perfusion scans. Untreated irradiated rats exhibited hyperemia, hypoperfusion, and perfusion defects of the irradiated lung. In penicillamine-treated rats, the appearance of perfusion defects was delayed, the peak incidence and severity of the defects was reduced, and recovery from pulmonary hypoperfusion was accelerated. Thus, using functional criteria, penicillamine appears to improve arterial perfusion and to ameliorate radiation injury in the rat lung.

  2. ESR study on radiation-induced radicals in carboxymethyl cellulose aqueous solution

    NASA Astrophysics Data System (ADS)

    Saiki, Seiichi; Nagasawa, Naotsugu; Hiroki, Akihiro; Morishita, Norio; Tamada, Masao; Kudo, Hisaaki; Katsumura, Yosuke

    2011-02-01

    Carboxymethyl cellulose (CMC) at highly concentrated aqueous solution undergoes radiation crosslinking reaction by ionizing irradiation. It is assumed that this radiation-induced reaction takes place by the indirect effect of water radiolysis, especially through the OH radical. However, the reaction mechanism is not well known. In this topic, ESR spectra of CMC radicals formed by reaction with OH radicals were measured directly in aqueous solution to identify the initially formed radical site. The ESR spectra were observed successfully and were interpreted as the overlapping of two spectra; a Triplet×Doublet spectrum and a Doublet spectrum. Each spectrum was assigned to radicals located on carboxymethyl groups linked to C6 and C2/C3.

  3. Baicalein protects mice against radiation-induced DNA damages and genotoxicity.

    PubMed

    Gandhi, Nitin Motilal

    2013-07-01

    Baicalein is the major flavonoid extracted from the root of Scutellaria baicaleins. This flavonoid is used extensively in Chinese herbal medicine. In the present study baicalein is evaluated for its radioprotective properties. Human blood cells when exposed to the γ-radiation ex vivo in presence of baicalein underwent the reduced DNA damage compared to the control. Baicalein administration prior to the whole-body γ-radiation (4 Gy) exposure of mice resulted in protecting the damage to the DNA as measured in their blood cells by alkaline comet assay. Mice when exposed to the radiation (whole body; 1.7 Gy) resulted in damage to the bone marrow as measured by micronucleated reticulocyte (MNRET) formation. Baicalein pre-treatment reduces the radiation induced damage to the bone marrow cells, as there was decrease in the percentage MNRET formation. These findings indicate radio-protecting ability of baicalein.

  4. A computational approach to the relationship between radiation induced double strand breaks and translocations

    NASA Technical Reports Server (NTRS)

    Holley, W. R.; Chatterjee, A.

    1994-01-01

    A theoretical framework is presented which provides a quantitative analysis of radiation induced translocations between the ab1 oncogene on CH9q34 and a breakpoint cluster region, bcr, on CH 22q11. Such translocations are associated frequently with chronic myelogenous leukemia. The theory is based on the assumption that incorrect or unfaithful rejoining of initial double strand breaks produced concurrently within the 200 kbp intron region upstream of the second abl exon, and the 16.5 kbp region between bcr exon 2 and exon 6 interact with each other, resulting in a fusion gene. for an x-ray dose of 100 Gy, there is good agreement between the theoretical estimate and the one available experimental result. The theory has been extended to provide dose response curves for these types of translocations. These curves are quadratic at low doses and become linear at high doses.

  5. Radiation-induced grafting of styrene onto polyimide ion track membranes

    NASA Astrophysics Data System (ADS)

    Friese, K.; Mehnert, R.; Placek, V.; Trautmann, C.; Angert, N.; Spohr, R.; Trautmann, Ch.

    1995-11-01

    The radiation induced grafting of styrene onto polyimide was carried out by applying the method of preirradiation as well as the simultaneous irradiation of polymer and monomer. The polymerization was initiated by gamma irradiation and by swift heavy ions. The result of these experiments was that no grafting occurs by applying the preirradiation method but grafting (up to 30%) is obtained by using the simultaneous method. For an explanation some ESR-experiments were carried out. We found that even the non-irradiated polyimide has a clear ESR signal with two different lines, probably as a result of absorbed oxygen and thermally formed radicals. The preirradiation method was not successful, because no peroxy-radicals are formed after irradiation. Grafting by initiation with heavy ions results in small grafting yields, but etching of the membranes is markedly reduced.

  6. X-ray microdiffraction analysis of radiation-induced defects in single grains of polycrystalline Fe

    PubMed Central

    Specht, E. D.; Walker, F. J.; Liu, Wenjun

    2010-01-01

    Single-crystal diffuse X-ray scattering was used to characterize radiation-induced defects in individual grains of a polycrystalline proton-irradiated Fe foil. The grains were probed with an intense 1 µm X-ray beam to demonstrate that both polycrystalline and micrometer-scale samples can be studied with single-crystal-like signal-to-noise. Scattering was measured with an X-ray-sensitive area detector, which measures intensity over a surface in reciprocal space. By scanning the X-ray energy, the intensity was measured over reciprocal-space volumes. Since the sample is not rotated, the real-space scattering volume does not change. Methods to minimize experimental artifacts arising from the use of an area detector are described. PMID:20157279

  7. Nuclear dynamics of radiation-induced foci in euchromatin and heterochromatin

    SciTech Connect

    Chiolo, Irene; Tang, Jonathan; Georgescu, Walter; Costes, Sylvain V.

    2013-10-01

    Repair of double strand breaks (DSBs) is essential for cell survival and genome integrity. While much is known about the molecular mechanisms involved in DSB repair and checkpoint activation, the roles of nuclear dynamics of radiation-induced foci (RIF) in DNA repair are just beginning to emerge. Here, we summarize results from recent studies that point to distinct features of these dynamics in two different chromatin environments: heterochromatin and euchromatin. We also discuss how nuclear architecture and chromatin components might control these dynamics, and the need of novel quantification methods for a better description and interpretation of these phenomena. These studies are expected to provide new biomarkers for radiation risk and new strategies for cancer detection and treatment.

  8. Graft polymerization using radiation-induced peroxides and application to textile dyeing

    NASA Astrophysics Data System (ADS)

    Enomoto, Ichiro; Katsumura, Yosuke; Kudo, Hisaaki; Soeda, Shin

    2011-02-01

    To improve the dyeing affinity of ultra high molecular weight polyethylene (UHMWPE) fiber, surface treatment by radiation-induced graft polymerization was performed. Methyl methacrylate (MMA), acrylic acid (AA) and styrene (St) were used as the monomers. The grafting yields as a function of storage time after irradiation were examined. Although the grafting yield of St after the sulfonation processing was quite low compared with those of MMA and AA, it was successfully dyed to a dark color with a cationic dye. Some acid dyes can dye the grafted fiber with AA. The acid dye is distributed to the amorphous domains of the AA grafted fiber. The dyeing concentration depended on the grafting yield, and the higher the grafting yield the darker the dye color.

  9. Characterization of Network Structure of Polyacrylamide Based Hydrogels Prepared By Radiation Induced Polymerization

    SciTech Connect

    Mahmudi, Naim; Sen, Murat; Gueven, Olgun; Rendevski, Stojan

    2007-04-23

    In this study network structure of polyacrylamide based hydrogels prepared by radiation induced polymerization has been investigated. Polyacrylamide based hydrogels in the rod form were prepared by copolymerization of acrylamide(AAm) with hydroxyl ethyl methacrylate(HEMA) and methyl acrylamide(MAAm) in the presence of cross-linking agent and water by gamma rays at ambient temperature. Molecular weight between cross-links and effective cross-link density of hydrogels were calculated from swelling as well as shear modulus data obtained from compression tests. The results have shown that simple compression analyses can be used for the determination of effective cross-link density of hydrogels without any need to some polymer-solvent based parameters as in the case of swelling based determinations. Diffusion of water into hydrogels was examined by analyzing water absorption kinetics and the effect of network, structure on the diffusion type and coefficient was discussed.

  10. Role of ATP as a Key Signaling Molecule Mediating Radiation-Induced Biological Effects.

    PubMed

    Kojima, Shuji; Ohshima, Yasuhiro; Nakatsukasa, Hiroko; Tsukimoto, Mitsutoshi

    2017-01-01

    Adenosine triphosphate (ATP) serves as a signaling molecule for adaptive responses to a variety of cytotoxic agents and plays an important role in mediating the radiation stress-induced responses that serve to mitigate or repair the injurious effects of γ radiation on the body. Indeed, low doses of radiation may have a net beneficial effect by activating a variety of protective mechanisms, including antitumor immune responses. On the other hand, ATP signaling may be involved in the radiation resistance of cancer cells. Here, focusing on our previous work, we review the evidence that low-dose γ irradiation (0.25-0.5 Gy) induces release of extracellular ATP, and that the released ATP mediates multiple radiation-induced responses, including increased intracellular antioxidant synthesis, cell-mediated immune responses, induction of DNA damage repair systems, and differentiation of regulatory T cells.

  11. Radiation-induced inactivation of enzymes - Molecular mechanism based on inactivation of dehydrogenases

    NASA Astrophysics Data System (ADS)

    Rodacka, Aleksandra; Gerszon, Joanna; Puchala, Mieczyslaw; Bartosz, Grzegorz

    2016-11-01

    Proteins, which have enzymatic activities play a fundamental role in the cell due to participation in most of biological processes. Oxidative-induced damage of enzymes often have marked effects on cellular processes, which in consequence determine cell functioning and survival. In this review, we focused on the radiation-induced inactivation of enzymes with particular emphasis on the inactivation of dehydrogenases. For a better understanding of this issue, the efficiency of products of water radiolysis (•OH, O2•- and H2O2) in enzyme inactivation has been analysed. Reactions of reactive oxygen species (ROS) with amino acids present in the active site of enzymes appear to have the greatest impact on enzyme inactivation.

  12. Functional properties of nisin-carbohydrate conjugates formed by radiation induced Maillard reaction

    NASA Astrophysics Data System (ADS)

    Muppalla, Shobita R.; Sonavale, Rahul; Chawla, Surinder P.; Sharma, Arun

    2012-12-01

    Nisin-carbohydrate conjugates were prepared by irradiating nisin either with glucose or dextran. Increase in browning and formation of intermediate products was observed with a concomitant decrease in free amino and reducing sugar groups indicating occurrence of the Maillard reaction catalyzed by irradiation. Nisin-carbohydrate conjugates showed a broad spectrum antibacterial activity against Gram negative bacteria (Escherichia coli, Pseudomonas fluorescence) as well as Gram positive bacteria (Staphylococcus aureus, Bacillus cereus). Results of antioxidant assays, including that of DPPH radical-scavenging activity and reducing power, showed that the nisin-dextran conjugates possessed better antioxidant potential than nisin-glucose conjugate. These results suggested that it was possible to enhance the functional properties of nisin by preparing radiation induced conjugates suitable for application in food industry.

  13. A review on radiation-induced nucleation and growth of colloidal metallic nanoparticles

    PubMed Central

    2013-01-01

    This review presents an introduction to the synthesis of metallic nanoparticles by radiation-induced method, especially gamma irradiation. This method offers some benefits over the conventional methods because it provides fully reduced and highly pure nanoparticles free from by-products or chemical reducing agents, and is capable of controlling the particle size and structure. The nucleation and growth mechanism of metallic nanoparticles are also discussed. The competition between nucleation and growth process in the formation of nanoparticles can determine the size of nanoparticles which is influenced by certain parameters such as the choice of solvents and stabilizer, the precursor to stabilizer ratio, pH during synthesis, and absorbed dose. PMID:24225302

  14. Prompt radiation-induced conductivity in polyurethane foam and glass microballoons

    SciTech Connect

    Hartman, E. Frederick; Zarick, Thomas Andrew; Sheridan, Timothy J.; Preston, Eric F.

    2014-06-01

    We performed measurements and analyses of the prompt radiation-induced conductivity (RIC) in thin samples of polyurethane foam and glass microballoon foam at the Little Mountain Medusa LINAC facility in Ogden, UT. The RIC coefficient was non-linear with dose rate for polyurethane foam; however, typical values at 1E11 rad(si)/s dose rate was measured as 0.8E-11 mho/m/rad/s for 5 lb./cu ft. foam and 0.3E-11 mho/m/rad/s for 10 lb./cu ft. density polyurethane foam. For encapsulated glass microballoons (GMB) the RIC coefficient was approximately 1E-15 mho/m/rad/s and was not a strong function of dose rate.

  15. High-dose radiation-induced meningiomas following acute lymphoblastic leukemia in children.

    PubMed

    Salvati, M; Cervoni, L; Artico, M

    1996-05-01

    The authors review three personal cases of patients who developed cerebral meningiomas following high-dose radiotherapy for acute lymphoblastic leukemia. Two patients were female and one male. Their ages when the leukemia appeared were between 11 and 15 years. All patients were treated with a course of prophylactic irradiation to the neuraxis for a total dose of 24 Gy. After an average interval of 10.4 years, all three patients presented a meningioma; histologically, one was meningothelial and two were fibrous. All three meningiomas presented atypical features. At follow-up 1, 4, and 4 years respectively after surgery, none of these patients presents neurological deficits or neuroradiological signs of recurrence. Forty-nine cases of high-dose radiation-induced meningioma are also reviewed.

  16. Nuclear dynamics of radiation-induced foci in euchromatin and heterochromatin.

    PubMed

    Chiolo, Irene; Tang, Jonathan; Georgescu, Walter; Costes, Sylvain V

    2013-10-01

    Repair of double strand breaks (DSBs) is essential for cell survival and genome integrity. While much is known about the molecular mechanisms involved in DSB repair and checkpoint activation, the roles of nuclear dynamics of radiation-induced foci (RIF) in DNA repair are just beginning to emerge. Here, we summarize results from recent studies that point to distinct features of these dynamics in two different chromatin environments: heterochromatin and euchromatin. We also discuss how nuclear architecture and chromatin components might control these dynamics, and the need of novel quantification methods for a better description and interpretation of these phenomena. These studies are expected to provide new biomarkers for radiation risk and new strategies for cancer detection and treatment.

  17. Bioinformatics methods for learning radiation-induced lung inflammation from heterogeneous retrospective and prospective data.

    PubMed

    Spencer, Sarah J; Bonnin, Damian Almiron; Deasy, Joseph O; Bradley, Jeffrey D; El Naqa, Issam

    2009-01-01

    Radiotherapy outcomes are determined by complex interactions between physical and biological factors, reflecting both treatment conditions and underlying genetics. Recent advances in radiotherapy and biotechnology provide new opportunities and challenges for predicting radiation-induced toxicities, particularly radiation pneumonitis (RP), in lung cancer patients. In this work, we utilize datamining methods based on machine learning to build a predictive model of lung injury by retrospective analysis of treatment planning archives. In addition, biomarkers for this model are extracted from a prospective clinical trial that collects blood serum samples at multiple time points. We utilize a 3-way proteomics methodology to screen for differentially expressed proteins that are related to RP. Our preliminary results demonstrate that kernel methods can capture nonlinear dose-volume interactions, but fail to address missing biological factors. Our proteomics strategy yielded promising protein candidates, but their role in RP as well as their interactions with dose-volume metrics remain to be determined.

  18. Radiation-Induced Organizing Pneumonia: A Characteristic Disease that Requires Symptom-Oriented Management

    PubMed Central

    Otani, Keisuke; Seo, Yuji; Ogawa, Kazuhiko

    2017-01-01

    Radiation-induced organizing pneumonia (RIOP) is an inflammatory lung disease that is occasionally observed after irradiation to the breast. It is a type of secondary organizing pneumonia that is characterized by infiltrates outside the irradiated volume that are sometimes migratory. Corticosteroids work acutely, but relapse of pneumonia is often experienced. Management of RIOP should simply be symptom-oriented, and the use of corticosteroids should be limited to severe symptoms from the perspective not only of cost-effectiveness but also of cancer treatment. Once steroid therapy is started, it takes a long time to stop it due to frequent relapses. We review RIOP from the perspective of its diagnosis, epidemiology, molecular pathogenesis, and patient management. PMID:28134830

  19. Experimental investigation of the factors influencing temperature dependence of radiation-induced attenuation in optical fiber

    NASA Astrophysics Data System (ADS)

    Jin, Jing; Xu, Raomei; Liu, Jixun; Song, Ningfang

    2014-03-01

    The effects of transmission wavelength, total dose and light source power on temperature dependence of radiation-induced attenuation (RIA) in Ge-P co-doped fibers were investigated. Three fibers irradiated up to total dose of 100 Gy and 10,000 Gy were used as test samples. A test system for temperature dependence of RIA was built up. The influence of transmission wavelength, total dose and light power on temperature sensitivity and linearity of RIA in three irradiated fibers were researched. The test results show that temperature sensitivity and linearity of RIA in optical fibers could be improved by adjusting total dose and selecting transmission wavelength. The light source power does not have obvious influence on temperature sensitivity and linearity. The Ge-P co-doped fiber at 850 nm transmission wavelength with higher total dose is a very promising candidate for fiber-optic temperature sensor.

  20. Toxicogenomic Effects in Rat Blood Leukocytes and Chemoprophylaxis of Radiation-Induced Carcinogenesis.

    PubMed

    Ivanov, S D; Bespalov, V G; Semenov, A L; Kovan'ko, E G; Aleksandrov, V A

    2016-03-01

    Toxicogenomic parameters were studied in the blood of female rats after exposure to ionizing γ-radiation in a dose of 4 Gy and chemoprophylaxis with α-difluoromethylornithine, eleutherococcus or leuzea extracts, which were used in animals with morphological manifestations of tumor growth under conditions of radiation-induced carcinogenesis. Life-time evaluation of toxicogenomic effects was carried out by express method for measurements of blood nucleotid DNA - fluorescent indication. The level of hyperaneu/polyploidy increased in the blood leukocytes of control rats 30 days after radiation exposure. A significant decrease of genotoxicity as a result of drug treatment in comparison with the number and multiplicity of tumors in irradiated animals was found only in the endocrine and reproductive organs of rats treated by eleutherococcus extract.